Destructive Effects Research Articles

Unraveling the Impacts of Submesoscale Thermal and Current Feedbacks on the Low Level Winds and Oceanic Submesoscale Currents

Abstract In this study, high-resolution coupled ocean-atmosphere simulations are performed over the Gulf Stream to investigate the influence of submesoscale (O(10 km)) thermal (TFB) and current (CFB) feedbacks on the low-level atmosphere and the oceanic submesoscale kinetic energy (SKE). At the submesoscale, TFB and CFB exhibit constructive and destructive effects on wind and surface stress, making this a more complex problem than for the mesoscale (O(100 km)). This co-influence alters classical coupling coefficients, posing a challenge to isolate individual coupling mechanisms. Here, the feedbacks are isolated separately by removing their imprint on the air-sea coupling fields in dedicated simulations. Both submesoscale TFB and CFB lead to a damping of the SKE. CFB causes eddy-killing by drag friction between currents and the atmosphere. However, while eddy-killing should be more efficient than its mesoscale counterpart due to a weaker wind response (less re-energization), its effect is hampered by an energization from TFB and by the highly transient nature of submesoscale flow, resulting in a modest 10% reduction in SKE. TFB also contributes to a reduction of SKE, mainly by causing a potential energy sink, associated with turbulent heat fluxes, especially at scales < 10km. The potential energy sink affects SKE through a decrease of baroclinic energy conversion, although this is slightly modulated by an increase in Ekman pumping by submesoscale CFB. Our results emphasize the importance of considering both TFB and CFB at the submesoscale, and highlight the limitations of mesoscale CFB parameterizations for submesoscale applications. Future parameterizations should be scale-aware and account for both TFB and CFB effects on momentum and heat fluxes.

Lecithin-based mixed polymeric micelles for activity improvement of curcumin against Staphylococcus aureus

Considering cellular uptake promotion of lecithin and high expression of phospholipase in S. aureus, we designed curcumin (Cur)-loaded soy lecithin-based mPEG-PVL copolymer micelles (MPPC). The effect of soy lecithin on the anti-S. aureus activity of the formulation was studied with cur-loaded mPEG-PVL micelles (MPC without soy lecithin) as control. It was found that MPPC enhanced the water-solubility of Cur, and showed slow and sustained release behavior of Cur. Although MPPC had the same anti-S. aureus activity as Cur, its activity was significantly higher than MPC due to the cellular uptake promotion of soybean lecithin. It was noted that MPPC had good inhibition or destruction effect on biofilm, significant cell membrane damage, strong inhibition effect on protease or lipase production, and obvious induction effect on ROS expression when compared with Cur and MPC. So, the introduction of soy lecithin could improve the antibacterial activity of Cur. The lecithin-based micelles would offer potential to deliver antibacterial drugs for improved therapeutic action.

Application of Geographic Information System (GIS), for Crisis Management

Natural disasters have always existed as a natural phenomenon throughout the life of the earth. The occurrence of natural disasters such as floods, earthquakes, storms, etc. in most cases have destructive effects on human settlements and heavy casualties on their residents. It has destroyed the buildings and infrastructures of such areas and imposed unfortunate economic and social consequences on cities and countries. Despite many scientific advances, mankind is still not able to prevent and resist these natural events. Natural disaster management and sustainable development are considered an integrated issue today. Due to limited resources, real development will not be possible without integration with disaster reduction programs. Earthquakes as a natural phenomenon do not have adverse results by themselves. What makes this phenomenon a disaster is the lack of prevention and lack of preparation to deal with its consequences. Therefore, one of the most necessary measures is to apply "principles of crisis management". Crisis management measures can be summarized in three parts: 1. Prevention, 2. Response, and 3. Reconstruction. Therefore, the title is the most important discussion in the strategy of reducing the effects of earthquakes. In this research, we seek to find the best location for crisis management support bases in Malair City, which first identified the effective factors and criteria in the location of relief centers during a crisis. Then, the AHP model was used to determine the importance and value of each criterion and effective elements in the decision, and a questionnaire was designed and distributed among experts and specialists. In the next step, the weight of each of the decision criteria and elements was determined using the hierarchical analysis process method and Expert Choice software. Then, using the field method, figures of the studied area were updated and prepared. In the next step, all information layers were converted to raster in the geographic information system (GIS). Finally, using the Index overlay method, the layers were combined. Three locations were suggested as the best locations for crisis management support bases in Malayer City. Among them, two options, one in the eastern part of the city on Molvi Street, and the other in the southern part of the city on Motahari Street, have been proposed as the best options. In terms of accessibility, they are in a good position. An option, that has a lower score, is located in the southeastern part of the city on Sheikh Kilini Street.

Crocin has a greater therapeutic role in the restoration of behavioral impairments caused by maternal social isolation in adolescent than in adult offspring probably through GSK-3beta downregulation

Parental stress drastically impairs cognitive and behavioral functions of the offspring. Social isolation, as one of the most stressful conditions for social animals including rats induces a wide range of destructive effects on behavioral functions. On the other hand, Crocin (active component of Crocus sativa) induces pro-cognitive and neuroprotective effects. In the present study, we aimed to investigate the effects of prolonged maternal social isolation (pre-gestational) and crocin treatment on cognitive and behavioral functions in both adolescent and adult offspring. Female adult rats (mothers) were socially isolated from PND 30 to PND 80 (50 days). The treatment was performed by intraperitoneal injections of crocin (10, 30, and 50 mg/kg) during PND 39–45 or PND 59–65 (7 consecutive days), in the rat offspring. Behavioral assessments were done when the offspring were on PND 45 (adolescent) or PND 65 (adult). The expression level of Glycogen synthase kinase-3 beta (GSK-3beta) in the hippocampus was measured using real-time PCR. The results showed maternal social isolation decreased locomotion and impaired memory in adolescents, and increased anxiety- and depressive-like behaviors and GSK-3beta level, and decreased pain threshold in both adolescents and adults. Crocin (30 and 50 mg/kg) restored or attenuated the effect of maternal social isolation on behavioral functions and GSK-3beta in adolescents and adults, with more effect in adolescents. In conclusion, we showed that crocin treatment can restore the destructive effects of maternal social isolation stress in the offspring, with stronger therapeutic effects in adolescents. Also, GSK-3beta downregulation may underlie the beneficial effects of crocin.

Study on the deterioration of mechanical properties of stainless steel S35657 exposed to overall stage of fire

Fires often have destructive effects on steel structures, putting the safety of building structures at serious risk. As a new austenite stainless steel, grade S35657, its in-fire and post-fire mechanical behavior has not been reported, which limits its application. In this paper, a total 68 stainless steel S35657 coupons were designed and tested, with 34 coupons used for in-fire tests and 34 for post-fire tests. The effects of heating temperatures, loading rates, and heating soaking times on the mechanical properties were investigated. The failure modes, as well as the stress-strain curves and mechanical properties, were acquired. Electron microscopy scanning analysis were also conducted on the coupons to study the fracture mechanisms at elevated temperatures. The test results showed a rapid decline in in-fire mechanical properties when the temperature exceeded 600 °C. The yield strength of the coupon at 1000 °C is only 9.1 % of that at room temperature. As the tensile rate increased, the strength of the coupon increased gradually. For post-fire coupons, there is no significant change in the mechanical properties of coupons at temperatures ranging from 20 °C to 900 °C. However, after reaching a temperature of 1000 °C, the coupon experienced a reduction in yield strength (up to 27.8 %) and an expansion in elongation (up to18.0 %), compared to the coupon at ambient temperature. This related to the change in grain size of the coupons after exposure to high temperatures. The heating soaking time has an insignificant effect on the post-fire mechanical properties of stainless steel S35657. Existing constitutive models in the literature cannot be well applied to stainless steel S35657, new constitutive models to predict the in-fire and post-fire mechanical properties have been established. Moreover, reduction factors for the key mechanical properties were compared with existing values, and new unified equations for stainless steel S35657 were proposed. Finally, a reliability analysis was performed to evaluate the proposed design rules, and it was deemed that the proposed design rules were reliable. The findings of this study will provide a reference for engineers in evaluating the in-fire and post-fire residual strength of stainless steel S35657, and offer guidance for fire resistance design and high-temperature repair reinforcement.

A novel recovery controllability method on temporal networks via temporal lost link prediction

Abstract Temporal networks are essential in representing systems where interactions between elements evolve over time. A crucial aspect of these networks is their controllability the ability to guide the network to a desired state through a set of control inputs. However, as these networks evolve, links between nodes can be lost due to various reasons, such as network failures, disruptions, or attacks. The loss of these links can severely impair the network’s controllability, making it challenging to recover desired network functions. In this paper, while investigating the destructive effects of various attacks on controllability processes in temporal networks, a new controllability recovery method is proposed, in which it prevents disruptions in this type of network processes by predicting lost links. In the proposed method, using network embedding and feature extraction, the dissimilarity of the nodes is calculated and then the missing links are predicted by designing a neural network. The results of the implementation of the proposed method on the datasets have demonstrates that the proposed method performed better than other conventional methods.

Bat Ecology and Microbiome of the Gut: A Narrative Review of Associated Potentials in Emerging and Zoonotic Diseases.

In this review, we tentatively tried to connect the most recent findings on the bat microbiome and to investigate on their microbial communities, that may vary even in conspecific hosts and are influenced by host physiology, feeding behavior and diet, social interactions, but also by habitat diversity and climate change. From a conservation perspective, understanding the potentially negative and indirect effects of habitat destruction on animal microbiota can also play a crucial role in the conservation and management of the host itself. According to the One Health concept, which recognizes an interdependence between humans, animals, and the environment, bat microbiota represents an indicator of host and environmental health, besides allowing for evaluation of the risk of emerging infectious diseases. We noticed that a growing number of studies suggest that animal microbiota may respond in various ways to changes in land use, particularly when such changes lead to altered or deficient food resources. We have highlighted that the current literature is strongly focused on the initial phase of investigating the microbial communities found in Chiroptera from various habitats. However, there are gaps in effectively assessing the impacts of pathogens and microbial communities in general in animal conservation, veterinary, and public health. A deeper understanding of bat microbiomes is paramount to the implementation of correct habitat and host management and to the development of effective surveillance protocols worldwide.

Collective behavior of active filaments with homogeneous and heterogeneous stiffness.

The collective dynamics of active biopolymers is crucial for many processes in life, such as cellular motility, intracellular transport, and division. Recent experiments revealed fascinating self-organized patterns of diverse active filaments, while an explicit parameter control strategy remains an open problem. Moreover, theoretical studies so far mostly dealt with active chains with uniform stiffness, which are inadequate in describing the more complicated class of polymers with varying stiffness along the backbone. Here, using Langevin dynamics simulations, we investigate the collective behavior of active chains with homogeneous and heterogeneous stiffness in a comparative manner. We map a detailed non-equilibrium phase diagram in activity and stiffness parameter space. A wide range of phase states, including melt, cluster, spiral, polar, and vortex, are demonstrated. The appropriate parameter combination for large-scale polar and vortex formation is identified. In addition, we find that stiffness heterogeneity can substantially modulate the phase behaviors of the system. It has an evident destructive effect on the long-ranged polar structure but benefits the stability of the vortex pattern. Intriguingly, we unravel a novel polar-vortex transition in both homogeneous and heterogeneous systems, which is closely related to the local alignment mechanism. Overall, we achieve new insights into how the interplay among activity, stiffness, and heterogeneity affects the collective dynamics of active filament systems.

Factors affecting the spiritual rehabilitation of people affected by natural disasters: a systematic review.

Every year, natural disasters in many countries lead to the destruction of infrastructure, loss of assets, and harm to the physical, mental, social, and spiritual health of people. The attention of policymakers and the media is mostly focused on the reconstruction of damaged buildings and the physical rehabilitation and recovery of the injured, while the spiritual rehabilitation of the people affected is often neglected. This study aims to identify the factors influencing the spiritual rehabilitation of people affected by natural disasters. This study was conducted using a systematic literature review following the PRISMA guidelines. Relevant studies were extracted from data sources, including MEDLINE (PubMed), Web of Science, Google Scholar, Embase, ProQuest, PsycInfo, Scopus, IranMedex, SID, and ISC. Systematic review studies, key journals, and conference proceedings related to the factors affecting the spiritual rehabilitation of individuals after natural disasters from January 1, 2020 to March 31, 2022 were included. Thematic analysis was used to analyze the obtained data. Initially, 1,753 studies were identified based on the initial search, and eventually, 22 final studies were included in the study. Based on the thematic analysis results, the factors influencing the spiritual rehabilitation of people affected by natural disasters were classified into four main themes and eleven sub-themes. The main themes included communication with God, strengthening religious beliefs, social participation, and meaning-making. The sub-themes included praying, using supplication, reading the holy book, praising God, believing in the afterlife, understanding the position and characteristics of the world, understanding the divine, participating in religious ceremonies, membership in supportive groups, the meaning of suffering and adversity, and the meaning of death. The results of this study demonstrate that the connection with the divine (God), strengthening religious beliefs, social participation, and meaning-making are influential factors in the spiritual rehabilitation of affected people after natural disasters. Incorporating these factors in the spiritual counseling and care of the affected people can improve their spiritual health after encountering the destructive effects of natural disasters. These findings can provide valuable insights for managing natural disasters through a holistic approach to the health of affected people, and can guide caregivers in implementing spiritual rehabilitation interventions.

Effect of facet joint resection on postoperative radiographic and clinical outcomes after microendoscopic laminectomy for single-level lumbar spinal stenosis

Facet joint destruction causes postoperative spinal instability, resulting in poor clinical outcomes after lumbar decompression surgery. However, the effect of facet joint destruction on radiographic and clinical outcomes after microendoscopic laminectomy (MEL) is unknown. Therefore, the current study aimed to examine the effect of facet joint resection on radiographic and clinical outcomes after single-level MEL surgery. This study included 116 patients with lumbar spinal canal stenosis (LSCS) who underwent single-level (L4/5) MEL surgery. Eligible patients were divided into the following groups: group P (facet joint preservation rate = 100%) (n = 70); group PR (50% ≤ the facet joint preservation rate < 100%) (n = 27); and group R (the facet joint preservation rate < 50%) (n = 19). The demographic characteristics of the patients, surgical data, pre- and 1-year postoperative radiographic measurements, and clinical outcomes were compared among the three groups. Moreover, pre- and postoperative radiographic and clinical outcomes were compared after adjusting the demographic characteristics of the patients and surgical data by the inverse probability weighting method with propensity scores. The three unweighted groups did not significantly differ in terms of demographic characteristics, surgical data, and pre- and postoperative radiographic and clinical outcomes. Even after adjusting for the demographic characteristics and surgical data, the pre- and postoperative radiographic and clinical outcomes were comparable among the three weighted groups. The extent of facet joint resection might have a minimal impact on radiographic and clinical outcomes at 1 year after single-level MEL surgery.

Physical Symptoms and Coping Strategies With Earthquake Stress Among Adults Living in Tent Cities: A Cross-Sectional Study.

This study aimed to examine the physical symptoms, coping strategies for earthquake stress and factors predicting coping strategies among adults staying in tent cities after an earthquake. A cross-sectional design was conducted. The study sample consisted of 706 adults residing in tent cities in three cities of earthquake-affected regions. Data were collected through face-to-face surveys and the Earthquake Coping Strategies Scale, starting from the 16th day after the earthquake in February-March 2023. Independent samples t-test, one-way analysis of variance, McNemar test and multiple linear regression analysis used for data analysis. The first three physical symptoms with the highest frequency after the earthquake were insomnia, frequent waking and difficulty falling asleep, respectively. Individuals with chronic illnesses, lower education levels, no previous experience with earthquakes and having undamaged homes more frequently used religious coping strategies. Individuals with higher incomes, employed individuals, non-smokers and those with having undamaged homes more frequently used positive reappraisal strategies. The present study concluded that physical symptoms were common among individuals in the post-earthquake period and that many individuals adopted religious coping strategies. Nurses can develop effective interventions for preventing physical and mental health problems in the post-earthquake period. They can contribute significantly as caregivers, leaders, researchers and advisors in health monitoring and improvement practices for individuals after earthquakes. The results of the study are instructive for designing prevention and improvement practices to minimise future destructive effects of earthquakes. Individuals mostly experienced sleep problems and preferred different coping styles in the early post-earthquake period. The physical and mental health of individuals can be improved by early intervention and encouraging effective coping methods after an earthquake. STROBE checklist. No patient or public involvement.

Solar Geoengineering: History, Methods, Governance, Prospects

Solar geoengineering, also called sunlight reflection or solar radiation modification (SRM), is a potential climate response that would cool the Earth's surface and reduce many other climate changes by scattering on order 1% of incoming sunlight back to space. SRM can only imperfectly correct for elevated greenhouse gases, but it might complement other climate responses to reduce risks, while also bringing new risks and new challenges to global governance. As climate alarm and calls for effective near-term action mount, SRM is attracting sharply increased attention and controversy, with many calls for expanded research and governance consultations along with ongoing concerns about risks, misuse, or overreliance. We review SRM's history, methods, potential uses and impacts, and governance needs, prioritizing the approach that is most prominent and promising, stratospheric aerosol injection. We identify several policy-relevant characteristics of SRM interventions and identify four narratives that capture current arguments over how SRM might be developed or used in sociopolitical context to either beneficial or destructive effect, with implications for near-term research, assessment, and governance activity.

Shake table tests on story-to-story pounding between adjacent RC buildings

Pounding between adjacent buildings and their devastating effects have been frequently reported during numerous major earthquakes. Although poundings exhibit more destructive effects on RC buildings compared to steel buildings, the majority of previous experimental studies have mainly concentrated on steel specimens. Furthermore, there has been a notable scarcity of extensive large-scale experimental studies on this subject. Therefore, the primary objective of this study is to experimentally determine the effects of different types of pounding on the seismic responses of RC buildings. To this aim, three half-scaled two-story RC specimens were constructed and were tested. In the tests, three cases were considered: (i) without pounding, (ii) pounding between taller and shorter buildings (slab-to-slab interaction at one floor), and (iii) pounding between buildings with equal heights (slab-to-slab interaction at the two floors). The experimental results showed that pounding and its types played a critical role in structural responses such as floor accelerations, displacements, hysteretic responses, and dynamic characteristics. Additionally, each pounding type led to different damage mechanisms in the specimens.

Rupture energy coupling of alkali washing tower cylinder

The energy generated by the container during the explosion induces destructive effects on the surrounding objects and itself, such as deformation, compression, rupture, etc. The explosive energy is one of the richest pieces of evidence in the analysis of the accident cause, and therefore a comprehensive analysis of the accident explosive energy is essential for determining accident properties. Considering the rupture accident of an alkali washing tower in an aromatic hydrocarbon plant as an example, the destructive energy and the rupture internal pressure are estimated to ascertain the explosive properties of the accident by analyzing the field damage characteristics. This study aims to conduct a comprehensive analysis and calculation of the energy associated with an alkali washing tower rupture accident. The objective is to determine the cause of the accident, which can be attributed to the combined effect of wall thickness reduction and fluctuations of production process parameters. The findings of this analysis will serve as a scientific basis for the examination of similar accidents and the formulation of safety protection measures.

The value of systemic immune inflammation index, white blood cell to platelet ratio, and homocysteine in predicting the instability of small saccular intracranial aneurysms

Inflammation has a destructive effect on the homeostasis of the vascular wall, which is involved in the formation, growth, and rupture of human intracranial aneurysms (IAs) disease progression. However, inflammation-related markers have not been well studied in the risk stratification of unruptured IAs. The purpose of this study was to investigate the predictive value of serum inflammatory markers in the unstable progression of small saccular intracranial aneurysms (SIAs). This study retrospectively included 275 patients with small SIAs (aneurysm diameter less than or equal to 7 mm), to compare the level difference of serum inflammatory complex marker systemic immune-inflammatory index (SII), white blood cell to platelet ratio (WPR), and homocysteine (Hcy) in patients with stable (asymptomatic unruptured) and unstable (symptomatic unruptured, ruptured) small SIAs. 187 patients (68%) had aneurysm-related compression symptoms and rupture outcomes. In the multivariate logistic regression after adjusting for baseline differences, SII, WPR, and Hcy were independent risk factors for the instability of small SIAs, the prediction model combined with other risk factors (previous stroke history, aneurysm irregularity) showed good predictive ability for the instability of small SIAs, with an area under the curve of 0.905. In addition, correlation analysis showed that SII, WPR, and Hcy also had significant differences in patients with symptomatic unruptured and ruptured small SIAs, and higher inflammation levels often promoted the disease progression of small SIAs. Higher levels of SII, WPR and Hcy can be used as independent predictors of instability of small SIAs. As an economical and convenient biomarker, it is crucial for clinical treatment strategies of stable small SIAs.

Inborn Errors of Immunity-related Immunological Mechanisms and Pharmacological Therapy Alternatives in Periodontitis.

Periodontitis is a frequent local inflammatory disease. The microbiota and repeated exposure to bacterial endotoxins triggers excessive inflammation through oral mucosal immunity, sometimes leading to a destructive effect on the supportive mucosal tissues around the teeth. Elimination of the pathogens and increasing the tolerance of the cellular immune response is crucial in addition to standard dental therapies like mechanical debridement. Based on our experience on immune-mediated diseases, especially primary immunodeficiency diseases (PIDs), we wrote this review to discuss the treatment alternatives for severe periodontal disease. Risk factors are malnutrition, vitamin deficiencies, smoking, systemic inherited and acquired immune-mediated diseases, infections, endocrinological diseases, and pharmacological agents may accompany periodontitis. The diagnosis and treatment of dietary deficiencies, as well as the addition of nutritional supplements, may aid in epithelial regeneration and immune system function. Recently, modifications to the therapeutic option for severe periodontitis have been made depending on the fact that the immune response against bacteria may modify the severity of periodontal inflammation. The anti-inflammatory therapies support or inhibit the host's immune response. The clinical approach to severe periodontitis should extend beyond classical therapies. There is a need for a diverse therapeutic strategy that supports the epithelial barrier, which is the crucial component of innate immunity against microbiota. Leukocytes are the main cellular component in periodontal inflammation. Anti-inflammatory therapeutic options directed at leukocytes, such as IL-17 and IL-23-targeted therapies, could be the candidates for the treatment of severe periodontitis. Therapy against other inflammatory cytokines, IL-1, IL-6, IL12, IL23, TNF-alpha, PGE2, and cytokine receptors, could also be used in periodontal inflammation control.

Evaluation of Mental Health Status of Obstetrics and Gynecology Assistants during the COVID-19 Pandemic in Iran - A Cross-sectional Study

Background: Some evidence shows that the COVID-19 pandemic has had negative effects on the mental health status of different sections of society, including the medical staff. Aims: The current study was conducted with the aim of investigating the mental health status of obstetrics and gynecology (OB-GYN) assistants during the COVID-19 pandemic in Iran. Methods: The present cross-sectional study was conducted in 23 hospitals across Iran in 2021 (January- March). Four hundred OB-GYN assistants were randomly and voluntarily enrolled in the study. The instrument used in this study was the 28-item General Health Questionnaire (GHQ-28), which had four subscales, including somatic symptoms, anxiety/ insomnia, social dysfunction and severe depression. To collect data and to reach respondents in distant areas, the questionnaires were provided to the OB-GYN assistants by the online platform. Results: The mean age of the OB-GYN assistants was 32.3±2.6 years, and all were female. Of 400 OB-GYN assistants, 132 (33%) had no distress and 268 (67%) had psychiatric distress. According to subscales scoring, 72 (18%), 68 (17%), 92 (23%) and 64 (16%) had severe distress in somatic symptoms, anxiety/ insomnia, social dysfunction and severe depression, respectively. Conclusion: Considering that more than half of the Iranian OB-GYN assistants had poor mental health, it seems that the COVID-19 pandemic has had a negative and destructive effect on the mental health of OB-GYN assistants. In this situation, they need psychological support and appropriate intervention.

Exosomal microRNA-363 mediates the destructive effect of M1 macrophages on chondrocytes by repressing G3BP2

M1 polarization of synovial macrophages contributes to cartilage degeneration and osteoarthritis (OA) development. However, limited knowledge is available about how M1 macrophages affect the biological properties of chondrocytes. This study aimed to explore the role of exosomal microRNAs (miRs) released from M1 macrophages in modulating the proliferation and survival of chondrocytes. Through bioinformatic analysis and experimental validation, we indicated that miR-363 was selectively induced in M1 macrophages (CD68+CD80+) but not M2 macrophages (CD68+CD206+). The upregulation of miR-363 in M1 macrophages depended on the activation of STAT1 signaling. Clinically, OA patients had a significantly higher miR-363 level in synovial fluid than control individuals without OA. Functional studies revealed that inhibition of miR-363 blocked the M1 macrophage polarization induced by lipopolysaccharide and IFN-γ. Moreover, exosomal miR-363 released from M1 macrophages significantly suppressed the proliferation and survival and induced inflammatory gene expression in chondrocytes. G3BP2 was identified as a target gene for miR-363 and could be negatively regulated by miR-363. Knockdown of G3BP2 recapitulated the effect of miR-363 overexpression on chondrocytes. Most importantly, enforced expression of G3BP2 attenuated miR-363-induced apoptosis and inflammatory response in chondrocytes. In conclusion, miR-363 plays an indispensable role in M1 macrophage polarization and can be released from M1 macrophages via exosomes to cause chondrocyte injury and inflammation. The miR-363/G3BP2 axis may represent a promising target for the prevention of OA development.

Influence of velocity pulse directivity on seismic response of cross-fault bridges

Pulse-type ground motions have special destructive effects on structures, and directivity is one of the fundamental characteristics of velocity pulses. In this paper, the impact of the velocity pulse directivity of seismic motions on both sides of the fault on the seismic response of fault-crossing bridges was quantified using the original records from the Chi-Chi earthquake in Taiwan. First, an automatic baseline correction method was applied to restore the permanent ground displacement, and the direction corresponding to the strongest pulse energy on both sides of the fault was identified based on continuous wavelet transformation. On this basis, the variability of the peak intensity of ground motions on the hanging wall and footwall in different directions, as well as the differences in pulse characteristics between the strongest pulse component and the two initial horizontal components, were analysed. Finally, a typical 5 × 30 m continuous girder bridge was considered as the research object to reveal the influence of the velocity pulse directivity on the seismic response of key parts on both sides of the fault. The results showed that the variability in the peak ground-motion intensity on the hanging wall of the fault was higher than that on the footwall. The displacement variability was up to 863 %, velocity was 262 %, and acceleration was 124 %. The pulse characteristics of the strongest pulse component were stronger than those of the parallel and vertical fault components, and its acceleration, velocity, and displacement response spectra were larger. The amplification effects of the velocity pulse directivity on the transverse bending moment, longitudinal bending moment, and torque of the pier bottom reached 1.3, 1.1, and 1.6, respectively. However, the amplification effect of the velocity pulse directivity on the relative displacement of the pier top, displacement of the main beam, and displacement of the bearing was more than 1.6 times, which was more significant than the internal force of the pier bottom.

Sintering process optimization of the additively manufactured pure copper parts through the metal paste deposited process

The fabrication process, sintering cycles through two sintering methods, microstructural and texture characterization, mechanical properties, and electrical conductivity of metal paste-deposited copper parts were investigated in this study. In the first condition, samples were air-debinded for carbon content removal followed by a sintering cycle. A sintering profile with the maximum sintering temperature and time of 1080 °C and 1 hr. was implemented after performing the air-debinding cycle at 250 °C for 2 hrs. In the second condition, samples were sintered in the environment of copper oxide for carbon removal in the early stages of the sintering cycle, i.e., 1070 °C for 1 hr and 1080 °C for 1, 2, and 3 hrs. The microstructural observations revealed coarser grains in the air-debinded samples, perhaps due to additional generated heat during carbon oxide formation, which may produce destructive effects on the boundary (HAGBs, twins, and CSL) volume and densification behavior of copper parts. However, through the second method, much finer grains and higher densities of boundaries were detected in the microstructure. Despite the significant effect of sintering conditions on the microstructure, texture interpretations revealed minor changes in the pole figures for different situations. Using the second sintering method and owing to the less carbon content and based on the density of the boundaries and their configurations, higher electrical conductivity (98.4±1.3 % IACS) was recorded by sintering the green parts. The comparison between the data from this study with other parts printed through other additive manufacturing techniques demonstrated a superior electrical conductivity level and acceptable balance between strain and strain notably with the sample sintered for 3 hrs.