[go: up one dir, main page]
More Web Proxy on the site http://driver.im/
You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled.
 
 
Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (200)

Search Parameters:
Keywords = danger theory

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
12 pages, 3767 KiB  
Article
Microseismic Electronic Fencing for Monitoring of Transboundary Mining in Mines
by Jianbiao Yang, Guangyin Lu, Lei Li and Dazhou Zhang
Appl. Sci. 2024, 14(23), 11043; https://doi.org/10.3390/app142311043 - 27 Nov 2024
Viewed by 397
Abstract
Mine transboundary mining has been occurring frequently in recent years, and this illegal behavior has brought great potential danger to mine safety while also causing greater losses of state-owned assets. However, the current method of monitoring transboundary mining is still mainly based on [...] Read more.
Mine transboundary mining has been occurring frequently in recent years, and this illegal behavior has brought great potential danger to mine safety while also causing greater losses of state-owned assets. However, the current method of monitoring transboundary mining is still mainly based on underground verification by supervisors, which is far from meeting the demand for supervision. Microseismic monitoring technology is effective for monitoring transboundary mining due to its ability to locate vibration signals. For mine transboundary mining monitoring, this paper proposes a microseismic electronic fence method focusing on mine boundary locating, which differs from the routine microseismic monitoring used in mining operations. This method focuses its key monitoring area on the mine boundary. The deployment mode, number of sensors, and localization theory are analyzed, and numerical simulation and field measurement data analysis results show that the microseismic electronic fence method can achieve a localization accuracy of 15–20 m for underground microseismic events in the vicinity of mine boundaries, which can be effectively applied to the monitoring of transboundary mining activities. Full article
Show Figures

Figure 1

Figure 1
<p>Schematic model and vibration signal recording: (<b>a</b>) example of 3D model (<b>b</b>) vibration signal recording.</p>
Full article ">Figure 2
<p>Five different arrangements of observation systems (the small red triangle is the surface sensor, the small blue triangle is the well sensor, and the green sphere is the events): (<b>a</b>) conventional arrangement (<b>b</b>) regular arrangement (<b>c</b>) circular arrangement (<b>d</b>) nested arrangement (<b>e</b>) nested arrangement (add well sensors).</p>
Full article ">Figure 3
<p>Comparison of localization results of different observing systems: (<b>a</b>) comparison of localization errors of 5 arrangements (<b>b</b>) comparison of horizontal and depth localization errors.</p>
Full article ">Figure 4
<p>Localization results for different depths at the scale of the observing system: (<b>a</b>) distribution of events (<b>b</b>) depth vs. localization error.</p>
Full article ">Figure 5
<p>Layout and localization results for different numbers of sensor arrangements (the small red triangle in (<b>a</b>,<b>c</b>) is the surface sensor, the small blue triangle is the well sensor, and the green sphere is the event): (<b>a</b>) 39 sensors (<b>b</b>) localization results for 6~39 sensors (<b>c</b>) 15 sensors (<b>d</b>) localization results for 15 sensors.</p>
Full article ">Figure 6
<p>Live view of station layout and vibration signal recording: (<b>a</b>) live view (<b>b</b>) vibration recording.</p>
Full article ">Figure 7
<p>Localization results: (<b>a</b>) seismic event distribution (<b>b</b>) horizontal direction (<b>c</b>) vertical direction.</p>
Full article ">
22 pages, 6029 KiB  
Article
Integrated Assessment of Security Risk Considering Police Resources
by Jieying Chen, Weihong Li, Yaxing Li and Yebin Chen
ISPRS Int. J. Geo-Inf. 2024, 13(11), 415; https://doi.org/10.3390/ijgi13110415 - 16 Nov 2024
Viewed by 584
Abstract
The existing research on security risk often focuses on specific types of crime, overlooking an integrated assessment of security risk by leveraging existing police resources. Thus, we draw on crime geography theories, integrating public security business data, socioeconomic data, and spatial analysis techniques, [...] Read more.
The existing research on security risk often focuses on specific types of crime, overlooking an integrated assessment of security risk by leveraging existing police resources. Thus, we draw on crime geography theories, integrating public security business data, socioeconomic data, and spatial analysis techniques, to identify integrated risk points and areas by examining the distribution of police resources and related factors and their influence on security risk. The findings indicate that security risk areas encompass high-incidence areas of public security issues, locations with concentrations of dangerous individuals and key facilities, and regions with a limited police presence, characterized by dense populations, diverse urban functions, high crime probabilities, and inadequate supervision. While both police resources and security risk are concentrated in urban areas, the latter exhibits a more scattered distribution on the urban periphery, suggesting opportunities to optimize resource allocation by extending police coverage to risk hotspots lacking patrol stations. Notably, Level 1 security risk areas often coincide with areas lacking a police presence, underscoring the need for strategic resource allocation. By comprehensively assessing the impact of police resources and public security data on spatial risk distribution, this study provides valuable insights for public security management and police operations. Full article
Show Figures

Figure 1

Figure 1
<p>Theoretical framework of the integrated assessment of security risk.</p>
Full article ">Figure 2
<p>Study area. Due to the signing of a confidentiality agreement with the Public Security Bureau, all drawings related to the research area have been encrypted, and it is not appropriate to add a compass.</p>
Full article ">Figure 3
<p>Research process of the integrated assessment of security risk.</p>
Full article ">Figure 4
<p>Distribution characteristics of public premises and their security risks in JY City: (<b>a</b>) political units; (<b>b</b>) commercial establishments; (<b>c</b>) transportation hubs; (<b>d</b>) community facilities; (<b>e</b>) public premises.</p>
Full article ">Figure 5
<p>Distribution characteristics of the security situation of security risk in JY City (partial). Due to the signing of a confidentiality agreement with the Public Security Bureau, all drawings related to the research area have been encrypted, and it is not appropriate to add a compass.</p>
Full article ">Figure 6
<p>Distribution characteristics of the urban morphology and their security risk in JY City: (<b>a</b>) political units; (<b>b</b>) commercial establishments; (<b>c</b>) transportation hubs; (<b>d</b>) community facilities.</p>
Full article ">Figure 7
<p>Distribution characteristics of the police resources of security risk in JY City (partial). Due to the signing of a confidentiality agreement with the Public Security Bureau, all drawings related to the research area have been encrypted, and it is not appropriate to add a compass.</p>
Full article ">Figure 8
<p>Hierarchical distribution map of integrated security risk points in JY City. Due to the signing of a confidentiality agreement with the Public Security Bureau, all drawings related to the research area have been encrypted, and it is not appropriate to add a compass.</p>
Full article ">Figure 9
<p>Hierarchical distribution map of the integrated security risk areas in JY City. Due to the signing of a confidentiality agreement with the Public Security Bureau, all drawings related to the research area have been encrypted, and it is not appropriate to add a compass.</p>
Full article ">
16 pages, 4286 KiB  
Article
Risk Assessment of Water Inrush from Coal Seam Floor with a PCA–RST Algorithm in Chenmanzhuang Coal Mine, China
by Weifu Gao, Yining Cao and Xufeng Dong
Water 2024, 16(22), 3269; https://doi.org/10.3390/w16223269 - 14 Nov 2024
Viewed by 548
Abstract
During coal mining, sudden inrushes of water from the floor pose significant risks, seriously affecting mine safety. This study utilizes the 3602 working face of the Chenmanzhuang coal mine as a case study, and the original influencing factors were downscaled using principal component [...] Read more.
During coal mining, sudden inrushes of water from the floor pose significant risks, seriously affecting mine safety. This study utilizes the 3602 working face of the Chenmanzhuang coal mine as a case study, and the original influencing factors were downscaled using principal component analysis (PCA) to obtain four key evaluation factors: water inflow, aquiclude thickness, water pressure, and exposed limestone thickness. The rough set theory (RST) was applied to determine the weights of the four main influencing factors as 0.2, 0.24, 0.36, and 0.2; furthermore, 19 groups of comprehensive values were calculated using the weighting method, and a water inrush risk assessment was conducted for several blocks within the working face. The results are presented as a contour map, highlighting various risk levels and identifying the water inrush danger zone on the coal seam floor. The study concludes that water inrush poses a threat in the western part of the working face, while the eastern area remains relatively safe. The accuracy and reliability of the model are demonstrated, providing a solid basis and guidance for predicting water inrush. Full article
Show Figures

Figure 1

Figure 1
<p>The location and geological structure of the Chenmanzhuang coal mine.</p>
Full article ">Figure 2
<p>Composite histogram of coal mine floor.</p>
Full article ">Figure 3
<p>Technology roadmap.</p>
Full article ">Figure 4
<p>Schematic figure.</p>
Full article ">Figure 5
<p>Water pressure contour map.</p>
Full article ">Figure 6
<p>Aquiclude thickness contour map.</p>
Full article ">Figure 7
<p>Comprehensive evaluation value contour map.</p>
Full article ">Figure 8
<p>Water inrush coefficient contour map.</p>
Full article ">
15 pages, 2532 KiB  
Article
Fake-News Attitude Evaluation in Terms of Visual Attention and Personality Traits: A Preliminary Study for Mitigating the Cognitive Warfare
by Stefano Menicocci, Viviana Lupo, Silvia Ferrara, Andrea Giorgi, Eleonora Serra, Fabio Babiloni and Gianluca Borghini
Behav. Sci. 2024, 14(11), 1026; https://doi.org/10.3390/bs14111026 - 1 Nov 2024
Viewed by 1062
Abstract
Although the Internet grants access to a large amount of information, it is crucial to verify its reliability before relying on it. False information is a dangerous medium that poses a considerable threat, as it impacts individuals’ perceptions and information processing, eventually shaping [...] Read more.
Although the Internet grants access to a large amount of information, it is crucial to verify its reliability before relying on it. False information is a dangerous medium that poses a considerable threat, as it impacts individuals’ perceptions and information processing, eventually shaping people’s behaviors. Misinformation can be weaponized, especially in cross-border conflicts, where it can be used as a means to erode social cohesion by manipulating public opinion and exacerbate tensions between nations. Cognitive Warfare targets human cognition shaping to be a realm of warfare. It entails the synergy of activities designed to alter perceptions of reality, along with other Instruments of Power, to affect attitudes and behaviors by influencing, protecting, or disrupting cognition on an individual, group, or population level to gain an advantage over an opponent. The objective of our study was to identify behavioral patterns and profile personality traits most likely to accept fake news as true, aiming to mitigate the phenomenon and impact of misinformation and disinformation, as well as addressing the concerning effects of Cognitive Warfare. Based on the Big Five Theory model, we investigated the variation in visual attention and level of Conscientiousness, Open-Mindedness, and Emotional Stability in regard to the capability to detect fake news. In this study, we measured Implicit reaction time (IRT) and visual behavior (Eye Tracker) while participants were shown both fake and real news. The results indicated that subjects who were able to differentiate between fake news and real news tended to exhibit lower levels of Open-Mindedness and focused heavily on the visual elements of the posts. Full article
(This article belongs to the Section Social Psychology)
Show Figures

Figure 1

Figure 1
<p>(<b>a</b>) On the left panel, the experimental setup during a recording is visible. We used the webcam as an eye tracker device to record the visual behavior of participants while exploring the posts. (<b>b</b>) On the right panel, the AOIs taken into consideration are shown.</p>
Full article ">Figure 2
<p>Experimental protocol. Before starting the experiment, the participants performed the eye tracker calibration and a short training trial. Successively, the participants watched a sequence of 8 news, and each of them remained on the screen for 22 s. Every two posts, participants were asked to indicate whether the two news were real or fake. Finally, 3 IATs were administered in random order for personality traits assessment.</p>
Full article ">Figure 3
<p>The first two pictures show an example of the training blocks. The third picture shows an example of the test block.</p>
Full article ">Figure 4
<p>The graph shows the difference in the NF on the AOI Post between the two conditions. The participants explored the AOI Post for a longer time (<span class="html-italic">p</span> = 0.02) when they were able to recognize the posts correctly. Asterisks indicate a statistically significant difference (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 5
<p>The graph shows the difference in the TV on the AOI Post between the two conditions. The participants spent a significantly longer time (<span class="html-italic">p</span> = 0.005) on the AOI Post when they were able to recognize the posts correctly. Asterisks indicate statistically significant differences (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 6
<p>The graph shows the difference in the RP on the AOI Post between the two conditions. The participants read and understood (<span class="html-italic">p</span> = 0.001) the AOI Post when they were able to recognize the posts correctly. Asterisks indicate a statistically significant difference (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 7
<p>The graph shows the difference in the TV on the AOI Title between the two conditions. The participants spent significantly less time (<span class="html-italic">p</span> = 0.02) on the AOI Title when they were able to recognize the posts correctly. Asterisks indicate a statistically significant difference (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 8
<p>The personality trait <span class="html-italic">Open-Mindedness</span> of participants able to recognize most of the fake news was significantly lower (<span class="html-italic">p</span> = 0.03) than those who did not. Asterisks indicate statistically significant differences (<span class="html-italic">p</span> &lt; 0.05). The Correct data distribution consisted of 22 values, while the Wrong group consisted of 28. No significant differences or trends were found for the IAT <span class="html-italic">Emotional Stability</span> and <span class="html-italic">Conscientiousness</span> between the two conditions.</p>
Full article ">
11 pages, 278 KiB  
Article
Shattering Reality: Monsters from the Multiverse
by Kristine Larsen
Humanities 2024, 13(6), 148; https://doi.org/10.3390/h13060148 - 29 Oct 2024
Viewed by 541
Abstract
Kaijū media frequently features dangerous scientific experiments as a central theme, invented by scientists who are falsely convinced that they both completely understand and control their advanced technology. In the past few decades, this has included the introduction of high-energy physics (HEP) experiments—especially [...] Read more.
Kaijū media frequently features dangerous scientific experiments as a central theme, invented by scientists who are falsely convinced that they both completely understand and control their advanced technology. In the past few decades, this has included the introduction of high-energy physics (HEP) experiments—especially mammoth particle accelerators—that, among other destructive results, allow for the entrance of equally large and dangerous creatures into our world from parallel dimensions. Public concerns voiced about the safety of the creation of two groundbreaking energy accelerators—the Relativistic Heavy Ion Collider (RHIC) in New York and the Large Hadron Collider (LHC) in Europe—in the early 21st century are tied to related science fiction media that capitalize on such fears (including Godzilla vs. Megaguirus [2000], Pacific Rim [2013], The Cloverfield Paradox [2018], The Kaiju Preservation Society [2022]). Particular attention is paid to the Netflix original series Stranger Things (2016–) as a detailed case study. This study concludes with an analysis of scientists’ attempts to embrace the popularity of Stranger Things in their communication with the general public, and suggests that ongoing issues with conspiracy theories have been fueled in part by such attempts, coupled with long-standing issues with the HEP community and their peculiar scientific naming conventions. Full article
27 pages, 4442 KiB  
Article
Research on Integration of Safety Policy System in Petrochemical Enterprises Based on Risk Hierarchical Control and Hidden Danger Investigation
by Kai Yu, Pingping Liu, Lujie Zhou and Rui Feng
Sustainability 2024, 16(20), 8746; https://doi.org/10.3390/su16208746 - 10 Oct 2024
Viewed by 816
Abstract
To enhance the risk management capacity of petrochemical enterprises, this paper presents a systematic and in-depth study of risk hierarchical control and hidden danger investigation technologies. Firstly, a risk hierarchical control system was developed based on text mining and Risk Breakdown Structure (RBS) [...] Read more.
To enhance the risk management capacity of petrochemical enterprises, this paper presents a systematic and in-depth study of risk hierarchical control and hidden danger investigation technologies. Firstly, a risk hierarchical control system was developed based on text mining and Risk Breakdown Structure (RBS) theory, categorizing risk alarm levels into four tiers: no alarm, light alarm, medium alarm, and heavy alarm. Secondly, a hidden danger investigation and management system was established by integrating a three-dimensional hidden danger grading model with the Plan-Do-Check-Act (PDCA) closed-loop principle. Finally, a cooperative management technology system for risk and hidden dangers in petrochemical enterprises was constructed and validated using Shandong Luqing Petrochemical Enterprise as a case study. The results indicated that the comprehensive risk level of Shandong Luqing Petrochemical Enterprise is classified as II, with a yellow light warning signal. They demonstrated a positive correlation between the risk hierarchical control system and the hidden danger investigation and management system. The findings of this research provide valuable guidance for improving safety management in petrochemical enterprises. Full article
(This article belongs to the Section Sustainable Chemical Engineering and Technology)
Show Figures

Figure 1

Figure 1
<p>Statistics of petrochemical accidents in China from 2013 to 2023.</p>
Full article ">Figure 2
<p>Accident time distribution map of China Petrochemical accident in 2023.</p>
Full article ">Figure 3
<p>Flow chart of petrochemical enterprise risk classification and control system.</p>
Full article ">Figure 4
<p>The three-dimensional hidden danger classification model.</p>
Full article ">Figure 5
<p>Flow chart of text mining.</p>
Full article ">Figure 6
<p>Hierarchical clustering diagram.</p>
Full article ">Figure 7
<p>Diagram of risk assessment index system for petrochemical enterprises.</p>
Full article ">Figure 8
<p>Three-dimensional risk classification model.</p>
Full article ">Figure 9
<p>Hidden danger closed-loop management flow chart.</p>
Full article ">Figure 10
<p>Relationship diagram between risk hierarchical control system and hidden danger investigation and management system.</p>
Full article ">Figure 11
<p>Petrochemical enterprise risk and hidden danger collaborative management technology system flow chart.</p>
Full article ">Figure 12
<p>Risk and hidden danger SPSS data view.</p>
Full article ">Figure 13
<p>Scatterplot of regression model.</p>
Full article ">Figure 14
<p>Regression standard residual histogram.</p>
Full article ">Figure 15
<p>P–P plot of regression standardized residuals.</p>
Full article ">
20 pages, 6774 KiB  
Article
A Driving Warning System for Explosive Transport Vehicles Based on Object Detection Algorithm
by Jinshan Sun, Ronghuan Zheng, Xuan Liu, Weitao Jiang and Mutian Jia
Sensors 2024, 24(19), 6339; https://doi.org/10.3390/s24196339 - 30 Sep 2024
Cited by 1 | Viewed by 583
Abstract
Due to the flammable and explosive nature of explosives, there are significant potential hazards and risks during transportation. During the operation of explosive transport vehicles, there are often situations where the vehicles around them approach or change lanes abnormally, resulting in insufficient avoidance [...] Read more.
Due to the flammable and explosive nature of explosives, there are significant potential hazards and risks during transportation. During the operation of explosive transport vehicles, there are often situations where the vehicles around them approach or change lanes abnormally, resulting in insufficient avoidance and collision, leading to serious consequences such as explosions and fires. Therefore, in response to the above issues, this article has developed an explosive transport vehicle driving warning system based on object detection algorithms. Consumer-level cameras are flexibly arranged around the vehicle body to monitor surrounding vehicles. Using the YOLOv4 object detection algorithm to identify and distance surrounding vehicles, using a game theory-based cellular automaton model to simulate the actual operation of vehicles, simulating the driver’s decision-making behavior when encountering other vehicles approaching or changing lanes abnormally during actual driving. The cellular automaton model was used to simulate two scenarios of explosive transport vehicles equipped with and without warning systems. The results show that when explosive transport vehicles encounter the above-mentioned dangerous situations, the warning system can timely issue warnings, remind drivers to make decisions, avoid risks, ensure the safety of vehicle operation, and verify the effectiveness of the warning system. Full article
(This article belongs to the Section Sensing and Imaging)
Show Figures

Figure 1

Figure 1
<p>Framework diagram of research ideas.</p>
Full article ">Figure 2
<p>Schematic diagram of monocular camera ranging principle.</p>
Full article ">Figure 3
<p>Dimensions of freight cars.</p>
Full article ">Figure 4
<p>Camera layout.</p>
Full article ">Figure 5
<p>Camera appearance.</p>
Full article ">Figure 6
<p>YOLOv4 network structure [<a href="#B19-sensors-24-06339" class="html-bibr">19</a>].</p>
Full article ">Figure 7
<p>Example of vehicle data images.</p>
Full article ">Figure 8
<p>Training images and box labels.</p>
Full article ">Figure 9
<p>Enhanced training dataset.</p>
Full article ">Figure 10
<p>The results of training.</p>
Full article ">Figure 11
<p>PR curve.</p>
Full article ">Figure 12
<p>Loss function curve.</p>
Full article ">Figure 13
<p>Capturing vehicle image information (safe vehicle distance).</p>
Full article ">Figure 14
<p>Capture vehicle image information (when the current rear distance is less than 60 m or the left and right distance is less than 1.5 m).</p>
Full article ">Figure 15
<p>Lane-changing rules.</p>
Full article ">Figure 16
<p>Flow chart of simulation steps for cellular automata.</p>
Full article ">Figure 17
<p>Traffic flow statistics.</p>
Full article ">Figure 18
<p>Statistical chart of average vehicle speed.</p>
Full article ">Figure 19
<p>Statistical chart of average vehicle density.</p>
Full article ">Figure 20
<p>Simulation process of cellular automata (time step 291).</p>
Full article ">Figure 21
<p>Program warning interface.</p>
Full article ">Figure 22
<p>Collision statistics without warning system.</p>
Full article ">Figure 23
<p>Collision statistics equipped with warning system.</p>
Full article ">
17 pages, 16821 KiB  
Article
Guessing Human Intentions to Avoid Dangerous Situations in Caregiving Robots
by Noé Zapata, Gerardo Pérez, Lucas Bonilla, Pedro Núñez, Pilar Bachiller and Pablo Bustos
Appl. Sci. 2024, 14(17), 8057; https://doi.org/10.3390/app14178057 - 9 Sep 2024
Viewed by 643
Abstract
The integration of robots into social environments necessitates their ability to interpret human intentions and anticipate potential outcomes accurately. This capability is particularly crucial for social robots designed for human care, as they may encounter situations that pose significant risks to individuals, such [...] Read more.
The integration of robots into social environments necessitates their ability to interpret human intentions and anticipate potential outcomes accurately. This capability is particularly crucial for social robots designed for human care, as they may encounter situations that pose significant risks to individuals, such as undetected obstacles in their path. These hazards must be identified and mitigated promptly to ensure human safety. This paper delves into the artificial theory of mind (ATM) approach to inferring and interpreting human intentions within human–robot interaction. We propose a novel algorithm that detects potentially hazardous situations for humans and selects appropriate robotic actions to eliminate these dangers in real time. Our methodology employs a simulation-based approach to ATM, incorporating a “like-me” policy to assign intentions and actions to human subjects. This strategy enables the robot to detect risks and act with a high success rate, even under time-constrained circumstances. The algorithm was seamlessly integrated into an existing robotics cognitive architecture, enhancing its social interaction and risk mitigation capabilities. To evaluate the robustness, precision, and real-time responsiveness of our implementation, we conducted a series of three experiments: (i) A fully simulated scenario to assess the algorithm’s performance in a controlled environment; (ii) A human-in-the-loop hybrid configuration to test the system’s adaptability to real-time human input; and (iii) A real-world scenario to validate the algorithm’s effectiveness in practical applications. These experiments provided comprehensive insights into the algorithm’s performance across various conditions, demonstrating its potential for improving the safety and efficacy of social robots in human care settings. Our findings contribute to the growing research on social robotics and artificial intelligence, offering a promising approach to enhancing human–robot interaction in potentially hazardous environments. Future work may explore the scalability of this algorithm to more complex scenarios and its integration with other advanced robotic systems. Full article
(This article belongs to the Special Issue Advances in Cognitive Robotics and Control)
Show Figures

Figure 1

Figure 1
<p>The robot identifies two potential targets for the human: a door and a couch. For each target, it generates a trajectory, excluding any obstacles that fall outside the human’s field of view from the planning process. Upon analysis of the generated trajectories, a potential collision with an obstacle is identified in the trajectory corresponding to the door. To avoid this collision and maintain the human’s safety, the robot considers a range of potential actions that could be taken to eliminate the collision in the human’s trajectory towards the door. (<b>a</b>) Estimation of trajectories from the person to the objects of interest. (<b>b</b>) Possible collision avoidance action, displacement of the robot to the obstacle.</p>
Full article ">Figure 2
<p>Schematic representation of the CORTEX architecture. The architecture is divided into two levels: cognitive and sub-cognitive. The cognitive level focuses on hosting <math display="inline"><semantics> <mi mathvariant="script">W</mi> </semantics></math> and the internal simulator (PyBullet), while the sub-cognitive level hosts the software that manages the low-level processes.</p>
Full article ">Figure 3
<p>Simulated scenario used to evaluate the robot’s ability to anticipate and mitigate risks. The room contains several key elements: an autonomous robot positioned near the door, a person located near the wall opposite the door, a door and a couch representing potential targets for the person, and a soccer ball as a dangerous object during human movement. The robot must use its internal model to predict possible trajectories of the person, acting proactively to ensure safety.</p>
Full article ">Figure 4
<p>Combined view showing the contents of <math display="inline"><semantics> <mi mathvariant="script">W</mi> </semantics></math> (<b>up-left</b>); a 2D graphical representation of <math display="inline"><semantics> <mi mathvariant="script">W</mi> </semantics></math> with two paths going from the person to the couch (<b>up-right</b>), the yellow path represents the route that would take the person directly to the couch without seeing the obstacle, while the red path shows the alternative route when the robot is moved; a zenithal view of the scene as rendered by Webots (<b>down-left</b>); and a 3D view of the internal simulator, PyBullet, with simple geometric forms representing the elements in the scene (<b>down-right</b>).</p>
Full article ">Figure 5
<p>Human-in-the-loop experiment (top left to bottom right). The upper half of each frame is the zenithal view rendered by the Webots simulator, where the red, blue, and green axes mark the reference system of the obstacle between the person and the couch. The lower half of each frame is representative of the first-person perspective, as observed by the human subject who was undertaking the experimental procedure. As can be seen, the obstacle was outside the field of view. When the robot approached the obstacle, frames 2–3, the subject turned left, overcoming it and safely reaching the couch.</p>
Full article ">Figure 6
<p>Real-world experiment (left to right). The upper half of the frame shows the view from the robot’s camera. The lower half shows a schematic view of <math display="inline"><semantics> <mi mathvariant="script">W</mi> </semantics></math>, with the person represented as a yellow circle, the backpack on the floor as a red square, and the target chair as a green square. The robot is colored dark red. The subject walks distractedly towards the chair (frame 1) and reacts when the robot starts moving (frame 2), changing direction and continuing.</p>
Full article ">
24 pages, 1894 KiB  
Review
Imprinting as Basis for Complex Evolutionary Novelties in Eutherians
by Maximillian Schuff, Amanda D. Strong, Lyvia K. Welborn and Janine M. Ziermann-Canabarro
Biology 2024, 13(9), 682; https://doi.org/10.3390/biology13090682 - 31 Aug 2024
Viewed by 1483
Abstract
The epigenetic phenomenon of genomic imprinting is puzzling. While epigenetic modifications in general are widely known in most species, genomic imprinting in the animal kingdom is restricted to autosomes of therian mammals, mainly eutherians, and to a lesser extent in marsupials. Imprinting causes [...] Read more.
The epigenetic phenomenon of genomic imprinting is puzzling. While epigenetic modifications in general are widely known in most species, genomic imprinting in the animal kingdom is restricted to autosomes of therian mammals, mainly eutherians, and to a lesser extent in marsupials. Imprinting causes monoallelic gene expression. It represents functional haploidy of certain alleles while bearing the evolutionary cost of diploidization, which is the need of a complex cellular architecture and the danger of producing aneuploid cells by mitotic and meiotic errors. The parent-of-origin gene expression has stressed many theories. Most prominent theories, such as the kinship (parental conflict) hypothesis for maternally versus paternally derived alleles, explain only partial aspects of imprinting. The implementation of single-cell transcriptome analyses and epigenetic research allowed detailed study of monoallelic expression in a spatial and temporal manner and demonstrated a broader but much more complex and differentiated picture of imprinting. In this review, we summarize all these aspects but argue that imprinting is a functional haploidy that not only allows a better gene dosage control of critical genes but also increased cellular diversity and plasticity. Furthermore, we propose that only the occurrence of allele-specific gene regulation mechanisms allows the appearance of evolutionary novelties such as the placenta and the evolutionary expansion of the eutherian brain. Full article
(This article belongs to the Section Biochemistry and Molecular Biology)
Show Figures

Figure 1

Figure 1
<p>Overview of most prominent theories explaining the evolution of genomic imprinting including their strengths (pro) and weaknesses (con). The center of the figure shows the chromosome in the gametes that will be inherited by the offspring (baby silhouette on the right). The lines crossing the respective chromosomes are alleles (genes), which are imprinted in the offspring. The top represents the silencing of the paternal allele, while the bottom represents the silencing of the maternal allele. Around the circle can be found the respective theories regarding the evolution of imprinting as discussed in detail in the text (part 2 of this manuscript). For each of the theories, one representative argument for (pro) or against (con) is provided as none of the theories explain all phenomena of genomic imprinting.</p>
Full article ">Figure 2
<p>Overview of gene dosage deviation in humans in physiological (blue, <b>left</b>) and pathological (red, <b>right</b>) conditions. There are several physiological, i.e., normal, ways of regulating the dosage of a gene. Imprinting is the inactivation of one parental allele/gene, while X-inactivation deactivates one chromosome and all genes on it. Gametes (sperm, ovum) also carry different genetic material from the parents (e.g., mitochondrial DNA is exclusively maternal), while allelic extrusion changes the amount of gene expression by silencing one allele independent of the parental origin. More details are provided in the text. a, b, c, and d represent alleles on chromosomes; M—maternal chromosome; P—paternal chromosome.</p>
Full article ">Figure 3
<p>Life cycle of imprinting during development. Blue: canonical imprinting, pink: non-canonical imprinting; DMR: Differentially methylated region; ICM: inner cell mass; TE: trophectoderm.</p>
Full article ">Figure 4
<p>Hypothesis for imprinting as a trigger of evolutionary novelties.</p>
Full article ">
15 pages, 17766 KiB  
Article
Experimental Investigation on Failure Characteristics of Pre-Holed Jointed Rock Mass Assisted with AE and DIC
by Xiaoming Yan, Yixing Liu, Shuo Yang, Yuhao Jin and Miao Chen
Appl. Sci. 2024, 14(17), 7655; https://doi.org/10.3390/app14177655 - 29 Aug 2024
Cited by 1 | Viewed by 597
Abstract
For jointed rock mass with anisotropy and discontinuity, the structure of the surrounding rock is constantly developing and changing during tunnel excavation. It is difficult to reasonably predict localized deformation of jointed rock mass by using the existing rock mechanics theory. In this [...] Read more.
For jointed rock mass with anisotropy and discontinuity, the structure of the surrounding rock is constantly developing and changing during tunnel excavation. It is difficult to reasonably predict localized deformation of jointed rock mass by using the existing rock mechanics theory. In this paper, the failure characteristic of pre-holed jointed rock mass with three joint angles is experimentally investigated by adopting the digital image correlation and acoustic emission methods. To avoid the influence of measurement error on Digital Image Correlation (DIC) from discontinuous deformation, parametric studies and an optimized algorithm are also included in DIC tests. Results indicate that the perpendicular-jointed condition (0° joints) is the most dangerous situation because of its comparatively lower strength and brittle failure mode with a shift energy release. For rocks with different jointed angles, localized deformation emerges after the material enters the plasticity. Significant localization occurs after the failure with cracks surrounding the center hole and pre-existing joints. Full article
(This article belongs to the Special Issue New Insights into Digital Rock Physics)
Show Figures

Figure 1

Figure 1
<p>Correlation computation for displacement within a deformation process [<a href="#B26-applsci-14-07655" class="html-bibr">26</a>].</p>
Full article ">Figure 2
<p>Transformation of the DIC mesh undergoing a deforming process.</p>
Full article ">Figure 3
<p>User interface of PhotoInfor and the auxiliary post-process program.</p>
Full article ">Figure 4
<p>DIC optimization using OPFPM algorithm: adjustment of subset block around the cracks during a process of correlation calculation [<a href="#B26-applsci-14-07655" class="html-bibr">26</a>].</p>
Full article ">Figure 5
<p>Schematic illustrations on samples made of rock-like materials with different joint angles.</p>
Full article ">Figure 6
<p>Stress-strain curve of uniaxial compression test on the rock-like material.</p>
Full article ">Figure 7
<p>Experimental setup.</p>
Full article ">Figure 8
<p>Laboratory sample.</p>
Full article ">Figure 9
<p>Cracking area selected dimensions of 230 × 240 pixels for parameter calibration for DIC processing.</p>
Full article ">Figure 10
<p>Comparison of volume strain diagrams varied with four selected subset radii. (<b>a</b>) Subset radius is set to 2 pixels. (<b>b</b>) Subset radius is set to 6 pixels. (<b>c</b>) Subset radius is set to 10 pixels. (<b>d</b>) subset radius is set to 14 pixels.</p>
Full article ">Figure 11
<p>Comparison of volume strain diagrams varied with four selected mesh densities. Mesh spacing in four cases is set at (<b>a</b>) 20 pixels (<b>b</b>) 10 pixels (<b>c</b>) 5 pixels and (<b>d</b>) 2 pixels.</p>
Full article ">Figure 12
<p>Revision of measurement error induced by discontinuous deformation via the OPFPM algorithm.</p>
Full article ">Figure 13
<p>Stress–strain curves of uniaxial compression tests for the intact sample and jointed samples with angles of 0, 45 and 90 degrees.</p>
Full article ">Figure 14
<p>Evolution of strain diagrams and AE activities of (<b>a</b>) 0° joints, (<b>b</b>) 45° joints, and (<b>c</b>) 90° joints. The unit of coordinates is in pixels (1 pixel corresponds to 0.05 mm in reality).</p>
Full article ">Figure 14 Cont.
<p>Evolution of strain diagrams and AE activities of (<b>a</b>) 0° joints, (<b>b</b>) 45° joints, and (<b>c</b>) 90° joints. The unit of coordinates is in pixels (1 pixel corresponds to 0.05 mm in reality).</p>
Full article ">
30 pages, 11884 KiB  
Article
Mechanisms of Thick-Hard Roof and Thin Aquifer Zone Floor Destruction and the Evolution Law of Water Inrush
by Min Cao, Shangxian Yin, Shuqian Li and Xu Wang
Water 2024, 16(16), 2304; https://doi.org/10.3390/w16162304 - 15 Aug 2024
Viewed by 750
Abstract
The collapse of thick-hard roofs after coal has been extracted is not a consequential process in all cases. Rather, it happens due to the augmentation of high stress conducted at depth, followed by a wider range of damage as the floor cracks. The [...] Read more.
The collapse of thick-hard roofs after coal has been extracted is not a consequential process in all cases. Rather, it happens due to the augmentation of high stress conducted at depth, followed by a wider range of damage as the floor cracks. The extent and spread of the cracks in the floor indicate the intensity of the collapse, and the mine will be submerged by the high-pressure water of the coal ash. Therefore, it is particularly important to study the mechanism of the combined effect of high stress on the roof and confined aquifer on the deformation and failure of the coal seam mining floor. This study analyzes and compares the impact of thick-hard magmatic rocks on the destruction of thin floor rock layers in coal seams. Plastic theory calculations are used to determine the plastic zone yield length of floor destruction under hard roof conditions, and the location and height of the maximum floor destruction depth are solved. An empirical formula and BP neural network are used to establish a prediction model for floor destruction. The results of the model’s prediction of the depth of floor failure were compared with the measured values, with an absolute error of 2.13 m and a residual of 10.3%, which was closer to the true values. The accuracy of the theoretical model and prediction model is verified using numerical simulation and on-site in situ measurements. Based on this, the deformation and destruction forms of the floor under pressure and the water inrush mechanism are summarized for mining under the condition of a thick-hard roof. Thus, the floor is subjected to high vertical stress, accompanied by significant disturbances generated during coal seam mining, resulting in intense working face pressures. The floor near the working face coal wall will experience severe compression and shear deformation and slide towards the goaf. The floor in the goaf is relieved of high vertical stress, and horizontal stress compression will result in shear failure, leading to floor heave and further increasing the height of the floor destruction zone. After the mining of the working face, the goaf will undergo two stages of re-supporting and post-mining compaction. During the re-supporting stage, the floor rock undergoes a transition from high-stress to low-stress conditions, and the instantaneous stress relief will cause plastic deformation and failure in the coal seam floor. The combined action of primary floor fractures and secondary fractures formed during mining can easily create effective water channels. These can connect to the aquifer or water-conducting structures, making them highly dangerous. The main modes of floor water inrush under the condition of a thick-hard roof are as follows: the high-stress mode, inducing a floor destruction zone connected to the water riser zone; the mining damage mode, connecting to water-conducting faults; the mining damage mode, connecting to water collapse columns; and the coupled water inrush mode, between the mining damage zone and the highly pressurized water floor. Full article
Show Figures

Figure 1

Figure 1
<p>Study area location (China administrative division data from geospatial data cloud).</p>
Full article ">Figure 2
<p>Hydrogeological conditions of mining area.</p>
Full article ">Figure 3
<p>The distribution of coal seam thickness.</p>
Full article ">Figure 4
<p>Comprehensive stratigraphic column.</p>
Full article ">Figure 5
<p>Thickness distribution of magmatic rock in coal seam roof.</p>
Full article ">Figure 6
<p>Calculation chart of plastic failure zone of rock mass.</p>
Full article ">Figure 7
<p>Schematic diagram of the failure form of the floor in the goaf.</p>
Full article ">Figure 8
<p>Schematic diagram of BP neural network structure.</p>
Full article ">Figure 9
<p>Training result of BP neural network.</p>
Full article ">Figure 10
<p>Analysis prediction results of BP neural network model. (<b>a</b>) Comparison between predicted and true values of validation samples. (<b>b</b>) Verify the relative error between the predicted value and the real value of the sample. (<b>c</b>) Verify sample residuals and residuals distribution.</p>
Full article ">Figure 11
<p>The 29205 working face 3D model.</p>
Full article ">Figure 12
<p>Contour map of vertical stress change of the roof and floor rock mass when the working face is mined to 400 m along the strike. (<b>a</b>) excavation 40 m; (<b>b</b>) excavation 80 m; (<b>c</b>) excavation 120 m; (<b>d</b>) excavation 160 m; (<b>e</b>) excavation 200 m; (<b>f</b>) excavation 240 m; (<b>g</b>) excavation 280 m; (<b>h</b>) excavation 320 m; (<b>i</b>) excavation 360 m; (<b>j</b>) excavation 400 m.</p>
Full article ">Figure 13
<p>Contour map of displacement change of the roof and floor rock mass when the working face is mined to 400 m along the strike. (<b>a</b>) excavation 40 m; (<b>b</b>) excavation 80 m; (<b>c</b>) excavation 120 m; (<b>d</b>) excavation 160 m; (<b>e</b>) excavation 200 m; (<b>f</b>) excavation 240 m; (<b>g</b>) excavation 280 m; (<b>h</b>) excavation 320 m; (<b>i</b>) excavation 360 m; (<b>j</b>) excavation 400 m.</p>
Full article ">Figure 14
<p>Contour map of the plastic zone distribution of the roof and floor rock mass when the working face is mined to 400 m along the strike. (<b>a</b>) excavation 40 m; (<b>b</b>) excavation 80 m; (<b>c</b>) excavation 120 m; (<b>d</b>) excavation 160 m; (<b>e</b>) excavation 200 m; (<b>f</b>) excavation 240 m; (<b>g</b>) excavation 280 m; (<b>h</b>) excavation 320 m; (<b>i</b>) excavation 360 m; (<b>j</b>) excavation 400 m.</p>
Full article ">Figure 15
<p>Drilling double stage water stopper layout plan.</p>
Full article ">Figure 16
<p>Drilling double stage water stopper layout sections.</p>
Full article ">Figure 17
<p>Curve of drilling leakage in the floor of the goaf.</p>
Full article ">Figure 18
<p>Curve of drilling leakage in the floor of the unmined area.</p>
Full article ">Figure 19
<p>Curve of drilling leakage of the floor at coal wall of working face.</p>
Full article ">Figure 20
<p>Distribution map of damaged area of coal seam floor in working face.</p>
Full article ">Figure 21
<p>Spatial and temporal evolution map of coal seam floor in working face.</p>
Full article ">Figure 22
<p>The evolution of the strain zone in the spatial and temporal dimensions along the strike of the coal face floor.</p>
Full article ">Figure 23
<p>Partition diagram of the floor after mining of coal seam floor in working face.</p>
Full article ">Figure 24
<p>Schematic diagram of the conduction between the failure zone of the working face bottom plate and the austenitic ash guide zone.</p>
Full article ">Figure 25
<p>Schematic diagram of the conduction between the floor failure zone and the water-conducting fault.</p>
Full article ">Figure 26
<p>Schematic diagram of the conduction between the floor failure zone and the water-conducting collapse column.</p>
Full article ">
24 pages, 1640 KiB  
Article
The Pigment World: Life’s Origins as Photon-Dissipating Pigments
by Karo Michaelian
Life 2024, 14(7), 912; https://doi.org/10.3390/life14070912 - 22 Jul 2024
Viewed by 2115
Abstract
Many of the fundamental molecules of life share extraordinary pigment-like optical properties in the long-wavelength UV-C spectral region. These include strong photon absorption and rapid (sub-pico-second) dissipation of the induced electronic excitation energy into heat through peaked conical intersections. These properties have been [...] Read more.
Many of the fundamental molecules of life share extraordinary pigment-like optical properties in the long-wavelength UV-C spectral region. These include strong photon absorption and rapid (sub-pico-second) dissipation of the induced electronic excitation energy into heat through peaked conical intersections. These properties have been attributed to a “natural selection” of molecules resistant to the dangerous UV-C light incident on Earth’s surface during the Archean. In contrast, the “thermodynamic dissipation theory for the origin of life” argues that, far from being detrimental, UV-C light was, in fact, the thermodynamic potential driving the dissipative structuring of life at its origin. The optical properties were thus the thermodynamic “design goals” of microscopic dissipative structuring of organic UV-C pigments, today known as the “fundamental molecules of life”, from common precursors under this light. This “UV-C Pigment World” evolved towards greater solar photon dissipation through more complex dissipative structuring pathways, eventually producing visible pigments to dissipate less energetic, but higher intensity, visible photons up to wavelengths of the “red edge”. The propagation and dispersal of organic pigments, catalyzed by animals, and their coupling with abiotic dissipative processes, such as the water cycle, culminated in the apex photon dissipative structure, today’s biosphere. Full article
(This article belongs to the Special Issue Feature Papers in Origins of Life 2024)
Show Figures

Figure 1

Figure 1
<p>The wavelength dependence of photon absorption on the leafs of 4 contemporary plant species. Absorption is strong over the solar spectrum, from the UV-C at about 205 nm to the red edge at 700 nm (0.7 μm). Photosynthetic efficiency, however, is usually less than 1%, with useful photons being limited to the chlorophyll peak at around 680 nm. The small dip in the absorption spectrum at 550 nm gives plants their green color. Reprinted with permission from Gates [<a href="#B20-life-14-00912" class="html-bibr">20</a>].</p>
Full article ">Figure 2
<p>Conjugated carbon molecules are more stable (lower Gibb’s free energy in the ground state) as compared to saturated molecules, but, more importantly, provide new collective electron orbitals, giving rise to excited states at energies adequate for the absorption of soft UV-C photons. The greater the conjugation number, the greater the wavelength of maximum absorption. The wavelength of maximum absorption of the chromophore can, therefore, be tuned simply by a protonation or deprotonation event. Conjugation is also important for giving molecules a conical intersection (see below) allowing rapid dissipation of the electronic excited state energy into heat (internal conversion). Reprinted with permission from Ref. [<a href="#B33-life-14-00912" class="html-bibr">33</a>]. 2023, K. Michaelian.</p>
Full article ">Figure 3
<p>The spectrum of UV light available at Earth’s surface before the origin of life at approximately 3.9 Ga and until at least 2.9 Ga (curves black and red, respectively). This spectrum in the UV-C may even have persisted throughout the entire Archean until 2.5 Ga [<a href="#B35-life-14-00912" class="html-bibr">35</a>]. Atmospheric CO<sub>2</sub>, H<sub>2</sub>O, SO<sub>2</sub> and probably some H<sub>2</sub>S, were responsible for the absorption of wavelengths shorter than ∼205 nm, and atmospheric gas aldehydes (e.g., formaldehyde and acetaldehyde, common photochemical products of CO<sub>2</sub> and water) absorbed between about 280 and 310 nm [<a href="#B15-life-14-00912" class="html-bibr">15</a>,<a href="#B36-life-14-00912" class="html-bibr">36</a>]), approximately corresponding to the UV-B region. By around 2.2 Ga (green curve), UV-C light at Earth’s surface was completely extinguished by the pigments of oxygen and ozone resulting from organisms performing oxygenic photosynthesis. The yellow curve corresponds to the present surface spectrum. Energy fluxes are for the sun at the zenith. Over 50 of the fundamental molecules of life are plotted at their wavelengths of maximum absorption: nucleic acids (black), amino acids (green), fatty acids (violet), sugars (brown), vitamins, co-enzymes, and cofactors (blue), and pigments (red). We propose that these molecules were dissipatively structured as UV-C pigments under this light. The font size is roughly proportional to the relative size of the respective molar extinction coefficient of the pigment. Adapted with permission from [<a href="#B17-life-14-00912" class="html-bibr">17</a>]. 2015, K. Michaelian.</p>
Full article ">Figure 4
<p>Absorption spectrum of adenosine in the soft UV-C region. The logarithm of molar extinction coefficient <math display="inline"><semantics> <mi>ϵ</mi> </semantics></math>, in units of M<sup>−1</sup>cm<sup>−1</sup>, is plotted as a function of wavelength. Peak absorption at 260 nm corresponds to the peak in the incident UV-C spectrum arriving at Earth’s surface during the Archean (<a href="#life-14-00912-f003" class="html-fig">Figure 3</a>). Large broadband absorption implies rapid (sub-picosecond) dissipation of the electronic excitation energy into heat through a conical intersection (<a href="#life-14-00912-f005" class="html-fig">Figure 5</a>). Public domain NIST Chemistry WebBook (<a href="https://webbook.nist.gov/chemistry" target="_blank">https://webbook.nist.gov/chemistry</a> accessed on 1 June 2024).</p>
Full article ">Figure 5
<p>A conical Intersection (CI) for excited adenine showing a degeneracy of the electronic excited state with the vibrational states superimposed on the electronic ground state after a UV-C photon absorption event (blue arrow), which induces a nuclear coordinate deformation from the molecules original structure in the Franck-Condon (FC) region to activation of an N9–H stretch or a ring-puckering motion known as pyramidalization (shown in the diagram). The most probable deformation depends on the incident photon energy and protonation state. It is this deformation, resulting from the excitation of an anti-bonding state (e.g., <math display="inline"><semantics> <mrow> <mi>π</mi> <mo>→</mo> <msup> <mi>π</mi> <mo>∗</mo> </msup> </mrow> </semantics></math>), which leads to a lowering of the excited potential energy surface such that it intersects with vibrational states of the electronic ground state, resulting in the conical intersection. Conical intersections provide rapid (sub-picosecond) dissipation of the electronic excitation energy into vibrational energy (heat). The quantum efficiency, <span class="html-italic">q</span>, for this dissipative route is very large (&gt;99%) for many of the fundamental molecules of life, making them photochemically stable and, more importantly for our theory, very efficient at UV-C photon dissipation. Another common form of coordinate transformation mediated through conical intersections is proton transfers within the molecule or with the solvent environment, and this may have relevance to enzymeless photon-induced denaturing of RNA and DNA [<a href="#B40-life-14-00912" class="html-bibr">40</a>] (see also <a href="#sec3dot1-life-14-00912" class="html-sec">Section 3.1</a>). The diagram is based on data from Andrew Orr-Ewing [<a href="#B41-life-14-00912" class="html-bibr">41</a>], Roberts et al. [<a href="#B42-life-14-00912" class="html-bibr">42</a>], Kleinermanns et al. [<a href="#B43-life-14-00912" class="html-bibr">43</a>], and Barbatti et al. [<a href="#B44-life-14-00912" class="html-bibr">44</a>]). Reprinted with permission from Ref. [<a href="#B12-life-14-00912" class="html-bibr">12</a>]. 2021, K. Michaelian.</p>
Full article ">Figure 6
<p>The photochemical dissipative structuring of adenine from 5 molecules of hydrogen cyanide (HCN) in water, first observed by Ferris and Orgel (1966) [<a href="#B27-life-14-00912" class="html-bibr">27</a>,<a href="#B30-life-14-00912" class="html-bibr">30</a>]. Four molecules of HCN (<b>1</b>) are transformed into the smallest stable oligomer (tetramer) of HCN, known as cis-2,3-diaminomaleonitrile (cis-DAMN) (<b>2</b>), which, under a constant UV-C photon flux, isomerizes into trans-DAMN (<b>3</b>) (also known as diaminofumaronitrile, DAFN) which can be converted, on absorbing two more UV-C photons, into an imidazole intermediate, 4-amino-1H-imidazole-5-carbonitrile (AICN) (<b>7</b>). Hot ground-state thermal reactions with another HCN molecule or its hydrolysis product formamide (or ammonium formate) lead to the purine adenine (<b>8</b>). This is a microscopic dissipative structuring process that ends in adenine [<a href="#B10-life-14-00912" class="html-bibr">10</a>,<a href="#B12-life-14-00912" class="html-bibr">12</a>], a UV-C pigment with a large molar extinction coefficient at the maximum intensity of the UV-C Archean surface solar spectrum (260 nm) and a peaked conical intersection facilitating rapid dissipation of photons at these wavelengths (<a href="#life-14-00912-f003" class="html-fig">Figure 3</a> and <a href="#life-14-00912-f004" class="html-fig">Figure 4</a>). Reprinted with permission from Ref. [<a href="#B12-life-14-00912" class="html-bibr">12</a>]. 2021, K. Michaelian.</p>
Full article ">Figure 7
<p>The wavelength of maximum absorption, and the molar extinction coefficient <math display="inline"><semantics> <mi>ϵ</mi> </semantics></math> (units of M<sup>−1</sup> cm<sup>−1</sup>) at that wavelength, of intermediate molecules on the way to the dissipative structuring of adenine (<a href="#life-14-00912-f006" class="html-fig">Figure 6</a>) is plotted on the spectrum of UV light available at Earth’s surface before the origin of life at approximately 3.9 Ga and until at least 2.9 Ga (curves black and red respectively). The general tendency towards absorption at greater photon intensities and towards greater molar extinction coefficients are the hallmarks of dissipative structuring. This is a microscopic analogy of the macroscopic dissipative structuring and growth in size and dissipating strength of a hurricane as it steers itself over warmer ocean surface water, due in part to algal pigment concentration [<a href="#B48-life-14-00912" class="html-bibr">48</a>]. The wavelengths of maximum absorption and the molar extinction coefficients at those wavelengths were obtained from references [<a href="#B30-life-14-00912" class="html-bibr">30</a>,<a href="#B49-life-14-00912" class="html-bibr">49</a>,<a href="#B50-life-14-00912" class="html-bibr">50</a>,<a href="#B51-life-14-00912" class="html-bibr">51</a>].</p>
Full article ">Figure 8
<p>Mechanism of dissipative structuring for the evolution towards molecular structures of ever greater photon dissipative efficacy (microscopic dissipative structuring) on route to the fundamental molecules (in this case, the UV-C pigment adenine, see <a href="#life-14-00912-f006" class="html-fig">Figure 6</a>). The high activation barriers between ground-state configurations mean that reactions will not proceed spontaneously but only on coupling to photon absorption events. Forward and backward rates depend on photon intensities I<math display="inline"><semantics> <mrow> <mo>(</mo> <mi>λ</mi> <mo>)</mo> </mrow> </semantics></math> at the different wavelengths of absorption for the two structures and on the phase-space widths of paths on their excited potential energy surface leading to the conical intersection giving rise to the particular transformation, implying different quantum efficiencies for the forward (<math display="inline"><semantics> <msubsup> <mi mathvariant="normal">q</mi> <mrow> <mi>i</mi> </mrow> <mi>j</mi> </msubsup> </semantics></math>) and backward (<math display="inline"><semantics> <msubsup> <mi mathvariant="normal">q</mi> <mrow> <mi>j</mi> </mrow> <mi>i</mi> </msubsup> </semantics></math>) reactions. For example, assuming that the intensity of the incident spectrum is uniform over wavelength, and since <math display="inline"><semantics> <mrow> <msubsup> <mi>q</mi> <mi>i</mi> <mi>j</mi> </msubsup> <mo>+</mo> <mo>⋯</mo> <msubsup> <mi>q</mi> <mi>i</mi> <mrow> <mi>I</mi> <mi>C</mi> </mrow> </msubsup> <mo>=</mo> <mn>1</mn> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <msubsup> <mi>q</mi> <mi>j</mi> <mi>i</mi> </msubsup> <mo>+</mo> <mo>⋯</mo> <msubsup> <mi>q</mi> <mi>j</mi> <mrow> <mi>I</mi> <mi>C</mi> </mrow> </msubsup> <mo>=</mo> <mn>1</mn> </mrow> </semantics></math> (where the “⋯” represents quantum efficiencies for other possible molecular transformations), those stationary states (corresponding macroscopically to molecular concentration profiles) with greater photon dissipative efficacy (higher quantum efficiency for internal conversion <math display="inline"><semantics> <msubsup> <mi mathvariant="normal">q</mi> <mi>j</mi> <mrow> <mi>I</mi> <mi>C</mi> </mrow> </msubsup> </semantics></math>) will therefore gradually become predominant under a continuous UV-C photon flux (since, in general, <math display="inline"><semantics> <mrow> <msubsup> <mi>q</mi> <mi>j</mi> <mi>i</mi> </msubsup> <mo>&lt;</mo> <msubsup> <mi>q</mi> <mi>i</mi> <mi>j</mi> </msubsup> </mrow> </semantics></math> if <math display="inline"><semantics> <mrow> <msubsup> <mi>q</mi> <mi>j</mi> <mrow> <mi>I</mi> <mi>C</mi> </mrow> </msubsup> <mo>&gt;</mo> <msubsup> <mi>q</mi> <mi>i</mi> <mrow> <mi>I</mi> <mi>C</mi> </mrow> </msubsup> </mrow> </semantics></math>), independently of the sign or size of the difference in the Gibb’s free energies <math display="inline"><semantics> <mo>Δ</mo> </semantics></math>G of the molecules. This process of selection of molecular concentration profiles of ever greater photon dissipative efficacy, driving evolution towards the right in the diagram, we call <span class="html-italic">natural thermodynamic selection</span>. It is considered in a simulated reaction-diffusion system within a vesicle for the abiogenesis of adenine from HCN under UV-C light in our reference [<a href="#B12-life-14-00912" class="html-bibr">12</a>]. Reprinted with permission from Ref. [<a href="#B12-life-14-00912" class="html-bibr">12</a>]. 2021, K. Michaelian.</p>
Full article ">Figure 9
<p>The ionization probability of adenine (<b>a</b>), guanine (<b>b</b>), and ribose as a function of energy compared to that of the nucleobase plus sugar complex, adenosine (<b>c</b>) and guanosine (<b>d</b>), and to adenosine monophosphate (<b>e</b>) and guanosine monophosphate (<b>f</b>). The thermodynamic dissipation theory argues that molecular complexation, such as a nucleobase attaching to ribose, will only occur if such an association leads to a system with greater photon dissipative efficacy. The conical intersection of ribose (and deoxyribose) to internal conversion is significantly more rapid than that of the nucleobase. By passing its photon-induced excitation energy onto ribose, the nucleoside complex becomes more efficient at dissipating than the nucleobase. Furthermore, the nucleobase is protected from ionization by hard UV-C (&lt;205 nm, ∼6 eV) since, as shown in the figure, the ionization energy of ribose is larger than that of the base. The bases are also protected from hydrolysis by polymerization, which can happen on attachment to ribose and phosphate [<a href="#B67-life-14-00912" class="html-bibr">67</a>]. Together, the base plus sugar is a more efficient and more robust system for dissipating the Archean UV surface spectrum than the molecules separated. Reprinted with permission from Ref. [<a href="#B66-life-14-00912" class="html-bibr">66</a>]. 2015, American Chemical Society.</p>
Full article ">Figure 10
<p>An example of increasing complexity through the dissipative structuring of an amino acid and DNA association, leading to greater photon dissipation. Tryptophan is attracted to its codon through a <math display="inline"><semantics> <mi>π</mi> </semantics></math>-ion interaction (also <math display="inline"><semantics> <mi>π</mi> </semantics></math>-stacking). Once within the Förster range of its DNA codon, it can transfer its photon-induced electronic excitation energy to one of the bases and, therefore, use the conical intersection of the base to dissipate its excitation energy rapidly into heat. Tryptophan may thus have initially been a UV-C antenna molecule for DNA, giving the complex greater photon dissipative efficacy than that of the two pigment molecules acting separately. This would have given the complex greater probability for UV-C induced denaturing and, therefore, reproduction, a process we refer to as “thermodynamic dissipative selection” [<a href="#B68-life-14-00912" class="html-bibr">68</a>].</p>
Full article ">Figure 11
<p>A simplified 2-dimensional schematic representation of the multi-dimensional entropy production surface (EPS) of a generalized phase space for a biosystem under a constant solar photon potential. The variables <span class="html-italic">x</span> and <span class="html-italic">y</span> at the origin of life may be, for example, the concentrations of different pigment molecules, while for an ecosystem of today, the variables may be the populations of different species. Three locally stable stationary states at local peaks in the entropy production surface are presented. On large enough external or internal perturbation, the system evolves from one stationary state to another. Although fluctuations are generally stochastic, the system will most often be found in those stationary states with a larger attraction basin, often corresponding to a higher peak in photon dissipation (e.g., the stationary state labeled “3”). Autocatalytic stationary states have higher peaks and larger attraction basins in this generalized phase space and are thus more probable. For molecules, this corresponds to concentration profiles with greater quantum efficiency for dissipation to the ground state through a conical intersection. For an ecosystem, this corresponds to animal and plant population profiles, giving greater total photon dissipation (time local climax ecosystems). If the system began in stationary state 1, its most probable future evolution would be 1→3, but any combination is possible. For the biosphere, the <span class="html-italic">x</span> and <span class="html-italic">y</span> variables might be the number of species in two different clades, and sub-peaks (not shown) corresponding to different species populations would exist on the main peaks, and evolution would usually be local, among the sub-peaks, but every once in a while a perturbation may be large enough (for example, an asteroid impact) to move the system from one main peak to another (e.g., 1→3, mammals y becoming more prominent than dinosaurs <span class="html-italic">x</span>). Point, cyclic, or even chaotic dynamics are allowed superimposed on these peaks [<a href="#B6-life-14-00912" class="html-bibr">6</a>]. The dimensionality of the generalized phase space is not fixed but evolves over time, providing new “shorter” routes to larger peaks of entropy production (e.g., the re-introduction of a population of wolves into the ecosystem of Yellow Stone National Park, see text). Reprinted with permission from Ref. [<a href="#B13-life-14-00912" class="html-bibr">13</a>]. 2022, K.Michaelian.</p>
Full article ">
22 pages, 7704 KiB  
Article
Seismic Risk Assessment and Analysis of Influencing Factors in the Sichuan–Yunnan Region
by Jia Wan, Ruiyin Dou and Tao Ma
Sustainability 2024, 16(14), 5968; https://doi.org/10.3390/su16145968 - 12 Jul 2024
Viewed by 784
Abstract
Investigating the distribution characteristics of earthquake disaster risks in the Sichuan–Yunnan region is of great importance for enhancing government emergency response capabilities and achieving sustainable regional development. This study, based on disaster systems theory, constructs a seismic risk evaluation index system for the [...] Read more.
Investigating the distribution characteristics of earthquake disaster risks in the Sichuan–Yunnan region is of great importance for enhancing government emergency response capabilities and achieving sustainable regional development. This study, based on disaster systems theory, constructs a seismic risk evaluation index system for the Sichuan–Yunnan region and employs the entropy method to determine the comprehensive risk index for earthquake disasters across 37 prefecture-level cities. The findings reveal the following: (1) High-risk areas for disaster-causing factors are located in the Hengduan Mountain region and the North–South Mountain Range Valley Region; medium-risk areas are distributed along the northwestern edge of the Sichuan Basin; low-risk areas are situated in the eastern part of the Sichuan Basin and the Yunnan Plateau. (2) High-risk disaster-prone environments are found in the Hengduan Mountain region; medium-risk areas are present on the Yunnan Plateau and the western part of the North–South Mountain Range Valley Region; low-risk areas are in the Sichuan Basin. (3) High-vulnerability areas include the central Sichuan Basin and Kunming on the Yunnan Plateau; medium-vulnerability areas are located in the eastern and western parts of the Sichuan Basin; low-vulnerability areas are in the less developed parts of the Yunnan Plateau, the North–South Mountain Range Valley Region, and the Hengduan Mountain region. (4) High-risk seismic disaster areas are concentrated in the developed regions of the Sichuan Basin and the Yunnan Plateau; medium-risk areas are concentrated in the western part of the North–South Mountain Range Valley Region; low-risk areas are sporadically distributed in the eastern parts of the Sichuan–Yunnan region. (5) The vulnerability of the population, economy, and lifeline systems significantly explain the variation in seismic risk levels, all exceeding 0.70; the synergistic effects of disaster-causing factor danger, disaster-prone environment stability, and disaster-prone environment sensitivity are the most pronounced, with explanatory power exceeding 0.85 after factor interaction. Full article
Show Figures

Figure 1

Figure 1
<p>Overview map of study area in the Sichuan–Yunnan region.</p>
Full article ">Figure 2
<p>Index system for seismic disaster risk assessment in the Sichuan–Yunnan region.</p>
Full article ">Figure 3
<p>Spatial distribution of seismic disaster. I is Sichuan Basin Area, II is Yunnan Plateau Area, III is North–South Mountain Range Valley Area, and IV is Hengduan Mountain Area.</p>
Full article ">Figure 4
<p>Spatial distribution of disaster-bearing bodies’ vulnerability index in the Sichuan–Yunnan region. (<b>A</b>) Disaster-bearing bodies’ vulnerability index in 2005; (<b>B</b>) disaster-bearing bodies’ vulnerability index in 2010; (<b>C</b>) disaster-bearing bodies’ vulnerability index in 2015; (<b>D</b>) disaster-bearing bodies’ vulnerability index in 2018. I is Sichuan Basin Area, II is Yunnan Plateau Area, III is North–South Mountain Range Valley Area, and IV is Hengduan Mountain Area.</p>
Full article ">Figure 5
<p>Spatial distribution of risk index for seismic disasters in the Sichuan–Yunnan region. I is Sichuan Basin Area, II is Yunnan Plateau Area, III is North–South Mountain Range Valley Area, and IV is Hengduan Mountain Area.</p>
Full article ">Figure 6
<p>Influence detection index of seismic risk in the Sichuan–Yunnan region.</p>
Full article ">
20 pages, 792 KiB  
Review
Temperature-Dependent Sex Determination in Crocodilians and Climate Challenges
by Boglárka Mária Schilling-Tóth, Scott M. Belcher, Josefine Knotz, Silvia Ondrašovičová, Tibor Bartha, István Tóth, Attila Zsarnovszky and Dávid Sándor Kiss
Animals 2024, 14(13), 2015; https://doi.org/10.3390/ani14132015 - 8 Jul 2024
Viewed by 1589
Abstract
The sex of crocodilians is determined by the temperature to which the eggs, and hence the developing embryo are exposed during critical periods of development. Temperature-dependent sex determination is a process that occurs in all crocodilians and numerous other reptile taxa. The study [...] Read more.
The sex of crocodilians is determined by the temperature to which the eggs, and hence the developing embryo are exposed during critical periods of development. Temperature-dependent sex determination is a process that occurs in all crocodilians and numerous other reptile taxa. The study of artificial incubation temperatures in different species of crocodiles and alligators has determined the specific temperature ranges that result in altered sex ratios. It has also revealed the precise temperature thresholds at which an equal number of males and females are generated, as well as the specific developmental period during which the sex of the hatchlings may be shifted. This review will examine the molecular basis of the sex-determination mechanism in crocodilians elucidated during recent decades. It will focus on the many patterns and theories associated with this process. Additionally, we will examine the consequences that arise after hatching due to changes in incubation temperatures, as well as the potential benefits and dangers of a changing climate for crocodilians who display sex determination based on temperature. Full article
(This article belongs to the Special Issue Sex Determination in Ectothermic Vertebrates)
Show Figures

Figure 1

Figure 1
<p>TSD2 pattern of <span class="html-italic">A. mississippiensis</span>: Males have a low proportion at decreased and very high temperatures, while at the intermediate temperatures, higher male ratios can be observed (dotted line). The blue and rosa bands describe the development of the PTs where a 50% male proportion was observed at 31.7 °C and 35.9 °C, while at 33.4 °C, the highest male ratio was found, according to the data of González (2019) [<a href="#B13-animals-14-02015" class="html-bibr">13</a>].</p>
Full article ">Figure 2
<p>Schematic figure for summarizing the involvement of steroid hormones, enzymes, and genes in the TSD mechanisms.</p>
Full article ">
19 pages, 2423 KiB  
Technical Note
A Feasible Region-Based Evaluation Method for the Renewable Energy Hosting Capacity with Frequency Security Constraints
by Zhi Zhang, Haibo Zhao, Qingyue Ran, Yao Wang, Juan Yu, Hongli Liu and Hui Duan
Energies 2024, 17(13), 3317; https://doi.org/10.3390/en17133317 - 5 Jul 2024
Viewed by 815
Abstract
As renewable energy becomes more widespread, the uncertainty of its output poses serious challenges for peak and frequency regulation of the power system. Evaluating a grid’s capacity to integrate renewable energy sources can provide an early-warning and decision-making basis for grid operation and [...] Read more.
As renewable energy becomes more widespread, the uncertainty of its output poses serious challenges for peak and frequency regulation of the power system. Evaluating a grid’s capacity to integrate renewable energy sources can provide an early-warning and decision-making basis for grid operation and scheduling. This paper presents a method for evaluating the hosting capacity of renewable energy, considering frequency security constraints. Introducing the system frequency nadir constraint into a system ensures that the frequency does not drop to a dangerous level in the event of power disturbances. The analytical characterization relation equation for the system frequency nadir constraint is constructed based on polynomial chaos expansion (PCE) theory. Furthermore, with the goal of minimizing the reduction in renewable energy, considering multiple flexible resources, like demand response (DR), Combined Heat and Power (CHP), energy storage, and Power-to-Gas (P2G), a renewable energy hosting capacity evaluation model that considers frequency security and flexibility resources is established. Finally, based on the concept of the feasible region, the maximum hosting capacity of a system’s renewable energy is visualized using the progressive vertex enumeration method. It identifies the safe operating region for renewable energy output that meets the safety constraints of power grid operations. The simulation results were validated using a modified IEEE 39 bus system. Full article
Show Figures

Figure 1

Figure 1
<p>The flowchart of the feasible region calculation process.</p>
Full article ">Figure 2
<p>Modified IEEE39 topology diagram.</p>
Full article ">Figure 3
<p>Typical scenario data.</p>
Full article ">Figure 4
<p>Frequency safety indicators.</p>
Full article ">Figure 5
<p>ON and OFF conditions of thermal power units without considering frequency constraints.</p>
Full article ">Figure 6
<p>ON and OFF conditions of thermal power units considering frequency constraints.</p>
Full article ">Figure 7
<p>The relationship between frequency safety indicators and the penetration rate of renewable energy.</p>
Full article ">Figure 8
<p>Penetration rate of renewable energy output under different conditions.</p>
Full article ">Figure 9
<p>The feasible region of the renewable energy hosting capacity.</p>
Full article ">Figure 10
<p>The feasible region of the renewable energy hosting capacity in an actual power grid.</p>
Full article ">
Back to TopTop