Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of pat...Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of patients with gallbladder stones and the literature suggests that at least 3%-10% of patients undergoing cholecystectomy will have common bile duct （CBD） stones. CBD stones may be discovered preoperatively, intraoperatively or postoperatively Multiple modalities are available for assessing patients for choledocholithiasis including laboratory tests, ultrasound, computed tomography scans （CT）, and magnetic resonance cholangiopancreatography （MRCP）. Intraoperative cholangiography during cholecystectomy can be used routinely or selectively to diagnose CBD stones. The most common intervention for CBD stones is ERCP. Other commonly used interventions include intraoperative bile duct exploration, either laparoscopic or open. Percutaneous, transhepatic stone removal other novel techniques of biliary clearance have been devised. The availability, of equipment and skilled practitioners who are facile with these techniques varies among institutions. The timing of the intervention is olden dictated by the clinical situation.展开更多
Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgica...Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated ＂tissue＂ in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. Early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical Education＇s （ACGME） has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients.展开更多
Study Objective: The purpose of the study is to present independent laboratory testing for a novel technology in air and on surfaces. Since 2020, public health goals have focused on improving indoor air quality. This ...Study Objective: The purpose of the study is to present independent laboratory testing for a novel technology in air and on surfaces. Since 2020, public health goals have focused on improving indoor air quality. This includes protection from airborne pathogens, such as tuberculosis, RSV, SARS-CoV-2, common cold or influenza viruses, measles, and others. Engineering controls are highly effective at reducing hazardous pathogens found in indoor air and from recontamination of surfaces. This occurs from a continuous cycle of settling of small, sustained airborne pathogens, which may become dehumidified, becoming airborne again, carried by room air currents around indoor spaces, then repeating the cycle. Methods: The novel technology utilizes a catalytic process to produce safe levels of hydrogen peroxide gas that are effective in reducing pathogens in the air and on surfaces. Air testing was performed with the MS2 bacteriophage, the test organism for ASHRAE standard 241, and methicillin-Resistant Staphylococcus aureus (MRSA). Surface testing was performed with SARS-COV-2 (Coronavirus COVID-19) and H1N1 (Influenza). Typical ventilation and filtration does not effectively remove disbursed pathogens from the entire facility, due to inconsistent air circulation and surface deposits of pathogens. Results: MS2 was reduced by 99.9%;MRSA was reduced by 99.9%;SARS-CoV-2 was reduced by 99.9%;H1N1 was reduced by 99.9%. Conclusion: This novel catalytic converter reduces a variety of pathogens in the air (99%) and on surfaces (99%), by actively disinfecting with the introduction of gaseous hydrogen peroxide. This active disinfection provides a strong solution for protecting the entire facility and its occupants.展开更多
Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure（...Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure（FBS） model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model（CECD） for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions（BOA）, and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.展开更多
Background:The transition metal copper enhances amyloidβaggregation and neurotoxicity,and in models of concomitant amyloid and tau pathology,copper also promotes tau aggregation.Since it is not clear if the effects o...Background:The transition metal copper enhances amyloidβaggregation and neurotoxicity,and in models of concomitant amyloid and tau pathology,copper also promotes tau aggregation.Since it is not clear if the effects of environmental copper upon tau pathology are dependent on the presence of pathological amyloidβ,we tested the effects of copper overload and complexing in disease models which lack pathological amyloidβ.Methods:We used cell culture and transgenic murine models to test the effects of environmental copper on tau phosphorylation.We used oral zinc acetate as a copper lowering agent in mice and examined changes in blood and brain metals through inductively coupled plasma mass spectroscopy.Behavioral effects of copper lowering were assessed with Morris water maze and novel object recognition tasks.Changes in tau phosphorylation were examined by phosphorylation specific antibodies on Western blots.Results:In human neuroblastoma cells,excess copper promoted tau phosphorylation and a copper complexing agent,tetrathiomolybdate,attenuated tau phosphorylation.In a transgenic mouse model expressing wild type human tau,copper-lowering by oral zinc suppressed plasma and brain levels of copper,and resulted in a marked attenuation of tau phosphorylation.No significant changes in behavior were observed with copper lowering,but a trend to improved recognition of the novel object was observed in zinc acetate treated mice.Conclusions:We propose that reduction of brain copper by blocking uptake of copper from the diet may be a viable strategy for modulating tau pathology in Alzheimer’s disease.The potential benefits of this approach are tempered by the absence of a behavioral benefit and by the health risks of excessive lowering of copper.展开更多
The advancements of sensing technologies,including remote sensing,in situ sensing,social sensing,and health sensing,have tremendously improved our capability to observe and record natural and social phenomena,such as ...The advancements of sensing technologies,including remote sensing,in situ sensing,social sensing,and health sensing,have tremendously improved our capability to observe and record natural and social phenomena,such as natural disasters,presidential elections,and infectious diseases.The observations have provided an unprecedented opportunity to better understand and respond to the spatiotemporal dynamics of the environment,urban settings,health and disease propagation,business decisions,and crisis and crime.Spatiotemporal event detection serves as a gateway to enable a better understanding by detecting events that represent the abnormal status of relevant phenomena.This paper reviews the literature for different sensing capabilities,spatiotemporal event extraction methods,and categories of applications for the detected events.The novelty of this review is to revisit the definition and requirements of event detection and to layout the overall workflow(from sensing and event extraction methods to the operations and decision-supporting processes based on the extracted events)as an agenda for future event detection research.Guidance is presented on the current challenges to this research agenda,and future directions are discussed for conducting spatiotemporal event detection in the era of big data,advanced sensing,and artificial intelligence.展开更多
The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GERD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions wi...The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GERD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions with lower morbidity and mortality, shorter hospital stay, faster convalescence, and less postoperative pain. One controversy in the treatment of GERD evolves around laparoscopic antireflux surgery （LAP, S） as the preferred treatmerit for Barrett＇s esophagus and the procedure＇s potential to reduce the risk of adenocarcinoma of the esophagus. GERD has also been associated with respiratory symptoms, asthma and laryngeal injury, and a second controversy prompts discussions about whether total or partial fundoplication is the more appropriate treatment for GERD. A new and promising alternative in the treatment of GERD is endoluminal therapy. Three types of this new treatment option will be discussed： radiofrequency energy delivered to the lower esophageal sphincter, the creation of a mechanical barrier at the gastroesophageal junction, and the direct endoscopic tightening of the lower esophageal sphincter. Laparoscopic surgery is discussed not only as a very effective treatment for GERD but also as permanent cure for achalasia. This review analyzes the three most important treatment options for achalasia： medications, pneumatic dilatation, and surgical therapy. Medications as the only true non-invasive option in the treatment of achalasia are not as effective as LAPS because of their short half-life and variable absorption due to the poor esophageal emptying. The second treatment option, pneumatic dilatation, involves the stretching of the lower esophagus and is still considered the most effective nonsurgical treatment for achalasia. Finally, surgical therapy for achalasia and the two major controversies concerning this laparoscopic treatment are discussed. The first involves the extent to which the myotomy is extended onto the stomach, and the second concerns the necessity and type of antir展开更多
Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models...Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models serve a dual purpose:they validate theoretical robustness and applicability via observational data and project future trends,thereby bridging the understanding and prediction of natural processes.In rapid advancements in computational methodologies and the continuous evolution of observational and experimental techniques,the development of numerical hydrological models based on physicallybased surface-subsurface process coupling have accelerated.Anchored in micro-scale conservation principles and physical equations,these models employ numerical techniques to integrate surface and subsurface hydrodynamics,thus replicating the macro-scale hydrological responses of watersheds.Numerical hydrological models have emerged as a leading and predominant trend in hydrological modeling due to their explicit representation of physical processes,heightened by their spatiotemporal resolution and reliance on interdisciplinary integration.This article focuses on the theoretical foundation of surface-subsurface numerical hydrological models.It includes a comparative and analytical discussion of leading numerical hydrological models,encompassing model architecture,numerical solution strategies,spatial representation,and coupling algorithms.Additionally,this paper contrasts these models with traditional hydrological models,thereby delineating the relative merits,drawbacks,and future directions of numerical hydrological modeling.展开更多
Hester-Dendy (HD) multi-plate samplers have been widely used by state and federal government agencies for bioassessment of water quality through use of macroinvertebrate community data. To help guide remediation and r...Hester-Dendy (HD) multi-plate samplers have been widely used by state and federal government agencies for bioassessment of water quality through use of macroinvertebrate community data. To help guide remediation and restoration efforts at the Niagara River Great Lakes Area of Concern site, a multi-agency study was conducted in 2014 to assess the contribution of seven major urban tributaries on the US side of the river toward the impairment of the Niagara River. As part of this study, macroinvertebrate communities were sampled using two co-located versions of HD samplers: one version used by the New York State Department of Environmental Conservation (NYSDEC) and another by the US Environmental Protection Agency Office of Research and Development. Samplers were deployed in tributaries in highly developed watersheds with high percent impervious surface. The two sampling methods varied in terms of number and size of plates, between-plate spacing, and deployment method. Comparison of the similarity/grouping of communities with multivariate ordination techniques, Nonmetric Multidimensional Scaling and Multi-Response Permutation Procedure, showed that both methods were able to detect differences in communities at stations, despite some grouping by month and method. The indices and metrics derived from the two HD methods were found to give comparable but not identical assessments of water quality. Despite their differences, the methods were robust with respect to water quality categories derived from indices used nationally (HBI) and by NY state (BAP). For the common richness metrics, total taxa and EPT richness, there was no statistical difference between means from 3 samplings. Some metrics, especially percent tolerant collector-gatherer individuals, did show significant differences at certain stations. Indicator Species Analysis showed some taxa associated with each method. The observed community differences were thought mostly due to the difference in sampler deployment position. .展开更多
Bus rapid transit (BRT) systems have been implemented in many cities over the past two decades. Widespread adoption of General Transit Feed Specification (GTFS), the deployment of high-fidelity bus GPS data tracking, ...Bus rapid transit (BRT) systems have been implemented in many cities over the past two decades. Widespread adoption of General Transit Feed Specification (GTFS), the deployment of high-fidelity bus GPS data tracking, and anonymized high-fidelity connected vehicle data from private vehicles have provided new opportunities for performance measures that can be used by both transit agencies and traffic signal system operators. This paper describes the use of trajectory-based data to develop performance measures for a BRT system in Indianapolis, Indiana. Over 3 million data records during the 3-month period between March and May 2022 are analyzed to develop visualizations and performance metrics. A methodology to estimate the average delay and schedule adherence is presented along a route comprised of 74 signals and 28 bus stations. Additionally, this research demonstrates how these performance measures can be used to evaluate dedicated and non-dedicated bus lanes with general traffic. Travel times and reliability of buses are compared with nearly 30 million private vehicle trips. Results show that median travel time for buses on dedicated bi-directional lanes is within one minute of general traffic and during peak periods the buses are often faster. Schedule adherence was observed to be more challenging, with approximately 3% of buses arriving within 1 minute on average during the 5AM hour and 5% of buses arriving 6 - 9 minutes late during the 5PM hour. The framework and performance measures presented in this research provide agencies and transportation professionals with tools to identify opportunities for adjustments and to justify investment decisions.展开更多
The val66met polymorphism of the bdnf gene, which is associated with compromised brain-derived neurotrophic factor (BDNF) signaling, impaired synaptic plasticity, and impaired learning, may increase one’s susceptibil...The val66met polymorphism of the bdnf gene, which is associated with compromised brain-derived neurotrophic factor (BDNF) signaling, impaired synaptic plasticity, and impaired learning, may increase one’s susceptibility to stress- and anxiety-related disorders. Indeed, previous work has reported greater anxiety-related behaviors and impairments of fear conditioning and extinction in individuals who carry the met allele that results from this polymorphism. Nevertheless, findings in this area of research have been equivocal. Thus, we examined the influence of the val66met polymorphism on fear conditioning, extinction, and extinction memory testing. One hundred and twenty healthy participants completed differential fear conditioning in a fear-potentiated startle paradigm, followed by extinction and extinction memory testing 24 and 48 hr later, respectively. Participants were genotyped for the val66met polymorphism and divided into met allele carriers and non-carriers. Results revealed that, although both met-carriers and non-carriers developed conditioned fear, met-carriers exhibited significantly weaker fear acquisition than non-carriers. This difference persisted throughout extinction and extinction memory testing and, during these last two days of testing, was primarily evident in females. These results are consistent with previous work demonstrating that this polymorphism is associated with impaired amygdala-dependent fear learning and extend such findings by demonstrating that females may be more sensitive to such effects.展开更多
Modern warfare has caused a large number of severe extremity injuries, many of which become infected. In more recent conflicts, a pattern of co-infection with Acinetobacter baumannii and methicillin-resistant Staphylo...Modern warfare has caused a large number of severe extremity injuries, many of which become infected. In more recent conflicts, a pattern of co-infection with Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus has emerged. We attempted to recreate this pattern in an animal model to evaluate the role of vascularity in contaminated open fractures. Historically, it has been observed that infected bones frequently appear hypovascular, but vascularity in association with bone infection has not been examined in animal models. Adult rats underwent femur fracture and muscle crush injury followed by stabilization and bacterial contamination with A. baumannii complex and methicillin-resistant Staphylococcus aureus.Vascularity and perfusion were assessed by micro CT angiography and SPECT scanning, respectively, at 1, 2 and 4 weeks after injury. Quantitative bacterial cultures were also obtained. Multi-bacterial infections were successfully created, with methicillin-resistant S. aureus predominating. There was overall increase in blood flow to injured limbs that was markedly greater in bacteria-inoculated limbs. Vessel volume was greater in the infected group. Quadriceps atrophy was seen in both groups, but was greater in the infected group. In this animal model, infected open fractures had greater perfusion and vascularity than non-infected limbs.展开更多
Agriculture is essential for providing food and maintaining food security while concurrently delivering multiple other ecosystem services. However,agricultural systems are generally a net source of greenhouse gases an...Agriculture is essential for providing food and maintaining food security while concurrently delivering multiple other ecosystem services. However,agricultural systems are generally a net source of greenhouse gases and ammonia. They, therefore, need to substantively contribute to climate change mitigation and net zero ambitions. It is widely acknowledged that there is a need to further reduce and mitigate emissions across sectors, including agriculture to address the climate emergency and emissions gap. This discussion paper outlines a collation of opinions from a range of experts within agricultural research and advisory roles following a greenhouse gas and ammonia emission mitigation workshop held in the UK in March 2022. The meeting identified the top mitigation priorities within the UK's agricultural sector to achieve reductions in greenhouse gases and ammonia that are compatible with policy targets. In addition, experts provided an overview of what they believe are the key knowledge gaps, future opportunities and cobenefits to mitigation practices as well as indicating the potential barriers to uptake for mitigation scenarios discussed.展开更多
A key goal of superconductivity research is to identify the mechanism by which electrons pair.Clues to the pairing mechanism lie in the resistive behavior(that is itself governed by electrons scattering off impurities...A key goal of superconductivity research is to identify the mechanism by which electrons pair.Clues to the pairing mechanism lie in the resistive behavior(that is itself governed by electrons scattering off impurities and dynamical fluctuations within the material)above the superconducting transition temperature T_(c).展开更多
To theeditor:The incidence of depression and obesity is on the rise,posing significant public health concerns.While the literature largely supports a positive correlation between depression and body mass index(BMI),I2...To theeditor:The incidence of depression and obesity is on the rise,posing significant public health concerns.While the literature largely supports a positive correlation between depression and body mass index(BMI),I2 earlier studies have suggested an inverse relationship or indicated a lack of association between depression and obesity.展开更多
Independent observation of the effects of agricultural management practices on soil organic carbon (SOC) with soil moisture content (SMC) is essential to quantify their potential relationships for sustainable ecosyste...Independent observation of the effects of agricultural management practices on soil organic carbon (SOC) with soil moisture content (SMC) is essential to quantify their potential relationships for sustainable ecosystems. Soil water retention studies and soil carbon stocks have been mapped in some areas worldwide. However, few studies have been conducted in the southeastern US, particularly in Mississippi. The objectives of this research study were to collect soil samples from fields chosen to be representative of the watersheds they are contained within, analyze the soil samples for carbon content and soil moisture content, and evaluate the relationship between SOC and different parameters (land use, vertical distribution, temporal distribution, and soil moisture content). Field sites were chosen based on their compositional similarity shared with the watershed as a whole in the Town Creek watershed (TCW) and Upper Pearl River watershed (UPRW) in Mississippi. Monthly soil samples from different depths (6 inch, 12 inch, and 24 inch) were collected from crop, pasture, and forest field areas. Soil samples were analyzed using bench analysis, elemental analysis, and statistical analysis. This study was able to demonstrate the SOC distribution in the soil layers across all three land uses studied. It was also shown that there does seem to be an interactive effect of parameters such as land use type, vertical distribution, and time on carbon accretion within the soil. Results of this study also determined that the near surface (6-in) layer was found to contain significantly more carbon than either the 12 inch or 24 inch layers (p 0.01) across all field types. There was found to be a high degree of variability within the soil moisture data and correlation between SOC and SMC. It was found that carbon amount is not influenced by SMC but SMC could be influenced by SOC.展开更多
Understanding dynamic stability of a ship on a resonance frequency is important because comparatively smaller external forces and moments generate larger motions.The roll motion is most susceptible because of smaller ...Understanding dynamic stability of a ship on a resonance frequency is important because comparatively smaller external forces and moments generate larger motions.The roll motion is most susceptible because of smaller restoring moments.Most studies related to the failure modes such as parametric roll and dead ship condition,identified by second generation of intact stability criteria(SGISC)are performed at a resonance frequency.However,the nature of resonance,where the model experiences an incremental roll motion,has not been well understood.In this study,nonlinear unsteady computational fluid dynamics(CFD)simulations were conducted to investigate the resonance phenomenon using a containership under a sinusoidal roll exciting moment.To capture the complexity of the phenomenon,simulations were conducted over a range of frequencies to cover the resonance frequency including lower and higher amplitudes.In addition to the resonance frequency,the phase shift between roll exciting moment and roll angle,as well as the phase difference between acceleration and roll angle,were found to have significant effects on the occurrence of resonance.展开更多
文摘Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of patients with gallbladder stones and the literature suggests that at least 3%-10% of patients undergoing cholecystectomy will have common bile duct （CBD） stones. CBD stones may be discovered preoperatively, intraoperatively or postoperatively Multiple modalities are available for assessing patients for choledocholithiasis including laboratory tests, ultrasound, computed tomography scans （CT）, and magnetic resonance cholangiopancreatography （MRCP）. Intraoperative cholangiography during cholecystectomy can be used routinely or selectively to diagnose CBD stones. The most common intervention for CBD stones is ERCP. Other commonly used interventions include intraoperative bile duct exploration, either laparoscopic or open. Percutaneous, transhepatic stone removal other novel techniques of biliary clearance have been devised. The availability, of equipment and skilled practitioners who are facile with these techniques varies among institutions. The timing of the intervention is olden dictated by the clinical situation.
文摘Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated ＂tissue＂ in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. Early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical Education＇s （ACGME） has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients.
文摘Study Objective: The purpose of the study is to present independent laboratory testing for a novel technology in air and on surfaces. Since 2020, public health goals have focused on improving indoor air quality. This includes protection from airborne pathogens, such as tuberculosis, RSV, SARS-CoV-2, common cold or influenza viruses, measles, and others. Engineering controls are highly effective at reducing hazardous pathogens found in indoor air and from recontamination of surfaces. This occurs from a continuous cycle of settling of small, sustained airborne pathogens, which may become dehumidified, becoming airborne again, carried by room air currents around indoor spaces, then repeating the cycle. Methods: The novel technology utilizes a catalytic process to produce safe levels of hydrogen peroxide gas that are effective in reducing pathogens in the air and on surfaces. Air testing was performed with the MS2 bacteriophage, the test organism for ASHRAE standard 241, and methicillin-Resistant Staphylococcus aureus (MRSA). Surface testing was performed with SARS-COV-2 (Coronavirus COVID-19) and H1N1 (Influenza). Typical ventilation and filtration does not effectively remove disbursed pathogens from the entire facility, due to inconsistent air circulation and surface deposits of pathogens. Results: MS2 was reduced by 99.9%;MRSA was reduced by 99.9%;SARS-CoV-2 was reduced by 99.9%;H1N1 was reduced by 99.9%. Conclusion: This novel catalytic converter reduces a variety of pathogens in the air (99%) and on surfaces (99%), by actively disinfecting with the introduction of gaseous hydrogen peroxide. This active disinfection provides a strong solution for protecting the entire facility and its occupants.
基金Supported by National Natural Science Foundation of China (Grant Nos.51375496,51205409)
文摘Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure（FBS） model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model（CECD） for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions（BOA）, and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.
基金by the U.S.Department of Veterans Affairs Merit Review(JFQ)NIH/NIA T32AG023477(KV)(P.I.Dr.Henryk Urbanski)+1 种基金NINDS NeuroNext 1U10NS077350(CM)NIH S10RR025512-01(MR).
文摘Background:The transition metal copper enhances amyloidβaggregation and neurotoxicity,and in models of concomitant amyloid and tau pathology,copper also promotes tau aggregation.Since it is not clear if the effects of environmental copper upon tau pathology are dependent on the presence of pathological amyloidβ,we tested the effects of copper overload and complexing in disease models which lack pathological amyloidβ.Methods:We used cell culture and transgenic murine models to test the effects of environmental copper on tau phosphorylation.We used oral zinc acetate as a copper lowering agent in mice and examined changes in blood and brain metals through inductively coupled plasma mass spectroscopy.Behavioral effects of copper lowering were assessed with Morris water maze and novel object recognition tasks.Changes in tau phosphorylation were examined by phosphorylation specific antibodies on Western blots.Results:In human neuroblastoma cells,excess copper promoted tau phosphorylation and a copper complexing agent,tetrathiomolybdate,attenuated tau phosphorylation.In a transgenic mouse model expressing wild type human tau,copper-lowering by oral zinc suppressed plasma and brain levels of copper,and resulted in a marked attenuation of tau phosphorylation.No significant changes in behavior were observed with copper lowering,but a trend to improved recognition of the novel object was observed in zinc acetate treated mice.Conclusions:We propose that reduction of brain copper by blocking uptake of copper from the diet may be a viable strategy for modulating tau pathology in Alzheimer’s disease.The potential benefits of this approach are tempered by the absence of a behavioral benefit and by the health risks of excessive lowering of copper.
基金supported by NSF[CNS 1841520 and ACI 1835507]NASA Goddard[80NSSC19P2033]the NSF Spatiotemporal I/UCRC IAB members.
文摘The advancements of sensing technologies,including remote sensing,in situ sensing,social sensing,and health sensing,have tremendously improved our capability to observe and record natural and social phenomena,such as natural disasters,presidential elections,and infectious diseases.The observations have provided an unprecedented opportunity to better understand and respond to the spatiotemporal dynamics of the environment,urban settings,health and disease propagation,business decisions,and crisis and crime.Spatiotemporal event detection serves as a gateway to enable a better understanding by detecting events that represent the abnormal status of relevant phenomena.This paper reviews the literature for different sensing capabilities,spatiotemporal event extraction methods,and categories of applications for the detected events.The novelty of this review is to revisit the definition and requirements of event detection and to layout the overall workflow(from sensing and event extraction methods to the operations and decision-supporting processes based on the extracted events)as an agenda for future event detection research.Guidance is presented on the current challenges to this research agenda,and future directions are discussed for conducting spatiotemporal event detection in the era of big data,advanced sensing,and artificial intelligence.
文摘The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GERD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions with lower morbidity and mortality, shorter hospital stay, faster convalescence, and less postoperative pain. One controversy in the treatment of GERD evolves around laparoscopic antireflux surgery （LAP, S） as the preferred treatmerit for Barrett＇s esophagus and the procedure＇s potential to reduce the risk of adenocarcinoma of the esophagus. GERD has also been associated with respiratory symptoms, asthma and laryngeal injury, and a second controversy prompts discussions about whether total or partial fundoplication is the more appropriate treatment for GERD. A new and promising alternative in the treatment of GERD is endoluminal therapy. Three types of this new treatment option will be discussed： radiofrequency energy delivered to the lower esophageal sphincter, the creation of a mechanical barrier at the gastroesophageal junction, and the direct endoscopic tightening of the lower esophageal sphincter. Laparoscopic surgery is discussed not only as a very effective treatment for GERD but also as permanent cure for achalasia. This review analyzes the three most important treatment options for achalasia： medications, pneumatic dilatation, and surgical therapy. Medications as the only true non-invasive option in the treatment of achalasia are not as effective as LAPS because of their short half-life and variable absorption due to the poor esophageal emptying. The second treatment option, pneumatic dilatation, involves the stretching of the lower esophagus and is still considered the most effective nonsurgical treatment for achalasia. Finally, surgical therapy for achalasia and the two major controversies concerning this laparoscopic treatment are discussed. The first involves the extent to which the myotomy is extended onto the stomach, and the second concerns the necessity and type of antir
基金supported by the National Natural Science Foundation of China(Grant Nos.41930759,42325502)the West Light Foundation of the Chinese Academy of Sciences(Grant No.xbzg-zdsys-202215)+2 种基金the Chinese Academy Sciences Talents Program,National Cryosphere Desert Data Centerthe Qinghai Key Laboratory of Disaster Prevention(Grant No.QFZ-2021-Z02)2023 First Batch of Science and Technology Plan Projects of Lanzhou City(Grant No.2023-1-49)。
文摘Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models serve a dual purpose:they validate theoretical robustness and applicability via observational data and project future trends,thereby bridging the understanding and prediction of natural processes.In rapid advancements in computational methodologies and the continuous evolution of observational and experimental techniques,the development of numerical hydrological models based on physicallybased surface-subsurface process coupling have accelerated.Anchored in micro-scale conservation principles and physical equations,these models employ numerical techniques to integrate surface and subsurface hydrodynamics,thus replicating the macro-scale hydrological responses of watersheds.Numerical hydrological models have emerged as a leading and predominant trend in hydrological modeling due to their explicit representation of physical processes,heightened by their spatiotemporal resolution and reliance on interdisciplinary integration.This article focuses on the theoretical foundation of surface-subsurface numerical hydrological models.It includes a comparative and analytical discussion of leading numerical hydrological models,encompassing model architecture,numerical solution strategies,spatial representation,and coupling algorithms.Additionally,this paper contrasts these models with traditional hydrological models,thereby delineating the relative merits,drawbacks,and future directions of numerical hydrological modeling.
文摘Hester-Dendy (HD) multi-plate samplers have been widely used by state and federal government agencies for bioassessment of water quality through use of macroinvertebrate community data. To help guide remediation and restoration efforts at the Niagara River Great Lakes Area of Concern site, a multi-agency study was conducted in 2014 to assess the contribution of seven major urban tributaries on the US side of the river toward the impairment of the Niagara River. As part of this study, macroinvertebrate communities were sampled using two co-located versions of HD samplers: one version used by the New York State Department of Environmental Conservation (NYSDEC) and another by the US Environmental Protection Agency Office of Research and Development. Samplers were deployed in tributaries in highly developed watersheds with high percent impervious surface. The two sampling methods varied in terms of number and size of plates, between-plate spacing, and deployment method. Comparison of the similarity/grouping of communities with multivariate ordination techniques, Nonmetric Multidimensional Scaling and Multi-Response Permutation Procedure, showed that both methods were able to detect differences in communities at stations, despite some grouping by month and method. The indices and metrics derived from the two HD methods were found to give comparable but not identical assessments of water quality. Despite their differences, the methods were robust with respect to water quality categories derived from indices used nationally (HBI) and by NY state (BAP). For the common richness metrics, total taxa and EPT richness, there was no statistical difference between means from 3 samplings. Some metrics, especially percent tolerant collector-gatherer individuals, did show significant differences at certain stations. Indicator Species Analysis showed some taxa associated with each method. The observed community differences were thought mostly due to the difference in sampler deployment position. .
文摘Bus rapid transit (BRT) systems have been implemented in many cities over the past two decades. Widespread adoption of General Transit Feed Specification (GTFS), the deployment of high-fidelity bus GPS data tracking, and anonymized high-fidelity connected vehicle data from private vehicles have provided new opportunities for performance measures that can be used by both transit agencies and traffic signal system operators. This paper describes the use of trajectory-based data to develop performance measures for a BRT system in Indianapolis, Indiana. Over 3 million data records during the 3-month period between March and May 2022 are analyzed to develop visualizations and performance metrics. A methodology to estimate the average delay and schedule adherence is presented along a route comprised of 74 signals and 28 bus stations. Additionally, this research demonstrates how these performance measures can be used to evaluate dedicated and non-dedicated bus lanes with general traffic. Travel times and reliability of buses are compared with nearly 30 million private vehicle trips. Results show that median travel time for buses on dedicated bi-directional lanes is within one minute of general traffic and during peak periods the buses are often faster. Schedule adherence was observed to be more challenging, with approximately 3% of buses arriving within 1 minute on average during the 5AM hour and 5% of buses arriving 6 - 9 minutes late during the 5PM hour. The framework and performance measures presented in this research provide agencies and transportation professionals with tools to identify opportunities for adjustments and to justify investment decisions.
文摘The val66met polymorphism of the bdnf gene, which is associated with compromised brain-derived neurotrophic factor (BDNF) signaling, impaired synaptic plasticity, and impaired learning, may increase one’s susceptibility to stress- and anxiety-related disorders. Indeed, previous work has reported greater anxiety-related behaviors and impairments of fear conditioning and extinction in individuals who carry the met allele that results from this polymorphism. Nevertheless, findings in this area of research have been equivocal. Thus, we examined the influence of the val66met polymorphism on fear conditioning, extinction, and extinction memory testing. One hundred and twenty healthy participants completed differential fear conditioning in a fear-potentiated startle paradigm, followed by extinction and extinction memory testing 24 and 48 hr later, respectively. Participants were genotyped for the val66met polymorphism and divided into met allele carriers and non-carriers. Results revealed that, although both met-carriers and non-carriers developed conditioned fear, met-carriers exhibited significantly weaker fear acquisition than non-carriers. This difference persisted throughout extinction and extinction memory testing and, during these last two days of testing, was primarily evident in females. These results are consistent with previous work demonstrating that this polymorphism is associated with impaired amygdala-dependent fear learning and extend such findings by demonstrating that females may be more sensitive to such effects.
基金Department of Defense,Congressionally Directed Medical Research Program OR 090206 to SG.The Small Animal Phenotyping Core provided faxiotron and micro CT imaging (P30DK056336 and P30DK079626)
文摘Modern warfare has caused a large number of severe extremity injuries, many of which become infected. In more recent conflicts, a pattern of co-infection with Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus has emerged. We attempted to recreate this pattern in an animal model to evaluate the role of vascularity in contaminated open fractures. Historically, it has been observed that infected bones frequently appear hypovascular, but vascularity in association with bone infection has not been examined in animal models. Adult rats underwent femur fracture and muscle crush injury followed by stabilization and bacterial contamination with A. baumannii complex and methicillin-resistant Staphylococcus aureus.Vascularity and perfusion were assessed by micro CT angiography and SPECT scanning, respectively, at 1, 2 and 4 weeks after injury. Quantitative bacterial cultures were also obtained. Multi-bacterial infections were successfully created, with methicillin-resistant S. aureus predominating. There was overall increase in blood flow to injured limbs that was markedly greater in bacteria-inoculated limbs. Vessel volume was greater in the infected group. Quadriceps atrophy was seen in both groups, but was greater in the infected group. In this animal model, infected open fractures had greater perfusion and vascularity than non-infected limbs.
基金supported with funding from the Scottish Government Strategic Research Programme (2022-2027, C2-1 SRUC)Biotechnology and Biological Sciences Research Council (BBSRC) (BBS/E/C/000I0320 and BBS/E/C/000I0330)+1 种基金support from UKRI-BBSRC (UK Research and InnovationBiotechnology and Biological Sciences Research Council) via grants BBS/E/C/000I0320 and BBS/E/C/000I0330Rothamsted Research Science Initiative Catalyst Award supported by BBSRC。
文摘Agriculture is essential for providing food and maintaining food security while concurrently delivering multiple other ecosystem services. However,agricultural systems are generally a net source of greenhouse gases and ammonia. They, therefore, need to substantively contribute to climate change mitigation and net zero ambitions. It is widely acknowledged that there is a need to further reduce and mitigate emissions across sectors, including agriculture to address the climate emergency and emissions gap. This discussion paper outlines a collation of opinions from a range of experts within agricultural research and advisory roles following a greenhouse gas and ammonia emission mitigation workshop held in the UK in March 2022. The meeting identified the top mitigation priorities within the UK's agricultural sector to achieve reductions in greenhouse gases and ammonia that are compatible with policy targets. In addition, experts provided an overview of what they believe are the key knowledge gaps, future opportunities and cobenefits to mitigation practices as well as indicating the potential barriers to uptake for mitigation scenarios discussed.
基金supported by the ERC under the European Union’s Horizon 2020 Research and Innovation Programme(Grant Agreement No.835279-Catch-22)。
文摘A key goal of superconductivity research is to identify the mechanism by which electrons pair.Clues to the pairing mechanism lie in the resistive behavior(that is itself governed by electrons scattering off impurities and dynamical fluctuations within the material)above the superconducting transition temperature T_(c).
文摘To theeditor:The incidence of depression and obesity is on the rise,posing significant public health concerns.While the literature largely supports a positive correlation between depression and body mass index(BMI),I2 earlier studies have suggested an inverse relationship or indicated a lack of association between depression and obesity.
文摘Independent observation of the effects of agricultural management practices on soil organic carbon (SOC) with soil moisture content (SMC) is essential to quantify their potential relationships for sustainable ecosystems. Soil water retention studies and soil carbon stocks have been mapped in some areas worldwide. However, few studies have been conducted in the southeastern US, particularly in Mississippi. The objectives of this research study were to collect soil samples from fields chosen to be representative of the watersheds they are contained within, analyze the soil samples for carbon content and soil moisture content, and evaluate the relationship between SOC and different parameters (land use, vertical distribution, temporal distribution, and soil moisture content). Field sites were chosen based on their compositional similarity shared with the watershed as a whole in the Town Creek watershed (TCW) and Upper Pearl River watershed (UPRW) in Mississippi. Monthly soil samples from different depths (6 inch, 12 inch, and 24 inch) were collected from crop, pasture, and forest field areas. Soil samples were analyzed using bench analysis, elemental analysis, and statistical analysis. This study was able to demonstrate the SOC distribution in the soil layers across all three land uses studied. It was also shown that there does seem to be an interactive effect of parameters such as land use type, vertical distribution, and time on carbon accretion within the soil. Results of this study also determined that the near surface (6-in) layer was found to contain significantly more carbon than either the 12 inch or 24 inch layers (p 0.01) across all field types. There was found to be a high degree of variability within the soil moisture data and correlation between SOC and SMC. It was found that carbon amount is not influenced by SMC but SMC could be influenced by SOC.
文摘Understanding dynamic stability of a ship on a resonance frequency is important because comparatively smaller external forces and moments generate larger motions.The roll motion is most susceptible because of smaller restoring moments.Most studies related to the failure modes such as parametric roll and dead ship condition,identified by second generation of intact stability criteria(SGISC)are performed at a resonance frequency.However,the nature of resonance,where the model experiences an incremental roll motion,has not been well understood.In this study,nonlinear unsteady computational fluid dynamics(CFD)simulations were conducted to investigate the resonance phenomenon using a containership under a sinusoidal roll exciting moment.To capture the complexity of the phenomenon,simulations were conducted over a range of frequencies to cover the resonance frequency including lower and higher amplitudes.In addition to the resonance frequency,the phase shift between roll exciting moment and roll angle,as well as the phase difference between acceleration and roll angle,were found to have significant effects on the occurrence of resonance.
