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A lawsuit filed in California claims the automaker’s philanthropic arm stole technology intended to help poor farmers, but it is not clear to what end
The identification of different air pollution sources is essential to effectively control atmospheric pollution, particularly in megacities of emerging countries with rapid economic development, such as the Metropolitan Area of Lima-Callao (MALC). The objective of this research was to identify the main sources of particulate matter pollution by applying bivariate polar plots and the k-means clustering algorithm. These statistical techniques were applied to hourly in situ data of four variables collected over a 5-year period (2015-2019) by the Automatic Air Quality Monitoring Network of the MALC: wind direction, wind speed, PM10, and PM2.5 concentrations. Average PM10 concentrations ranged from 34 μg m-3 (CDM station) to 126.7 μg m-3 (VMT station), while average PM2.5 concentrations ranged from 16.8 μg m-3 (CDM station) to 41.2 μg m-3 (ATE station). The diurnal variation of PM presented two peaks, one in the morning (from 0800 to 1000 h) and the other at night (from 1900 to 2300 h), with the highest concentrations of PM10 recorded at the ATE (0800 h: 155.8 μg m-3) and VMT (2100 h: 154.6 μg m-3) stations, and PM2.5 at the ATE station (0800 h: 60.3 μg m-3 and 2300 h: 37.5 μg m-3). The results showed that the contributions of PM10 are directly related to emissions from industrial activities, automotive fleet, construction, demolition, wind erosion, and the suspension and resuspension of particulates from unpaved roads. Meanwhile, high concentrations of PM2.5 are mainly attributed to vehicle exhaust emissions, industrial emissions, secondary particulate formation, and drag by the action of the winds. The major source of particulate matter contamination is the vehicle fleet, and within this, automobiles, station wagons, combi vans, and 2 and 3-wheel motorcycles are those that have the greatest contribution. These results were supported by non-parametric statistical tests such as Kruskal-Wallis and Mann-Whitney U and validated by the conditional bivariate probability function. The findings of this work may help to implement pollution prevention and control strategies in the future within this South American megacity.
The planar B13+1 cluster, a prototypical molecular 'Wankel motor', has captivated the scientific community with its exceptional stability as well as rotor action. The present study is an exploration of how incremental electron injection/abstraction influences the electronic structure of B13 clusters with B13+1 as a reference one. It has been found that seven different charge states (from + 3 to - 3) of B13 cluster are possible, among which B13-1 triplet is the lowest energy cluster. For B13n clusters, n =  + 3 to - 2, the clusters are planar and possess C2v symmetry and their relative atomic arrangement is similar to B13+1 ground state (GS) structure in which a triangular boron core is encircled by ten peripheral boron atoms. B13-3 cluster has a different geometric arrangement of atoms like that of the B13+1 transition state (TS) structure; remains planar, possesses C2v symmetry. The different atomic arrangement of B13-3 can be assigned to the electronic structural relaxation to reduce the electronic stress arising from high negative charge. B13+1 cluster is characterized by a unique electron density distribution in the cluster plane which is analogous to a 'tri-spoke wheel' configuration. In it, three spokes of electron dense lines connect the triangular core to the nearly circular periphery. The present study unveils how the injection or abstraction of electrons modifies the electronic topology in the cluster plane and how the spoke-wheel geometry evolves. It has been found that, in the + 3 and + 2 charge states, the wheel consists of four and five spokes respectively. On the other hand, for all other clusters, the overall electronic topology resembles that of the tri-spoke wheel-like B13+1 cluster. AIM analysis helped to trace out and characterize the evolution of the spoke-wheel topology with electron density at ring critical points and the bond paths. Density Functional Theory (DFT), utilizing the 6-311 + G(d) basis set and the PBE1PBE hybrid density functional, has been employed to determine the minimum energy structures of B13 clusters with different charged states. The calculations have been performed using a superfine integration grid and very tight optimization settings, as implemented in GAUSSIAN 09 Revision D.01. To address potential instabilities in SCF calculations, wavefunction stability has been thoroughly analysed. AIM analysis and various real-space functions, including electron density, Localized Orbital Locator (LOL), Phase-Space defined Fisher Information Density (PS-FID), and Electron Localization Function (ELF), have been investigated. Multiwfn 3.8 was utilized for plotting these functions.
Although asphalt mixtures can be applied to railway tracks due to their viscoelastic properties, caution is required, as their ductility and brittleness are highly sensitive to temperature variations. In recent years, interest in the application of asphalt in railway infrastructure has increased, driven by the development of modified mixtures and the broader availability of performance-enhancing additives. Additionally, evaluation methods for railway tracks should be adapted to account for the distinct loading mechanisms involved, which differ from those of conventional roadways. In this study, the comprehensive properties of asphalt binders, mixtures, and testing methods-including physical and engineering characteristics-were assessed to improve the performance of asphalt concrete layers for potential applications in railroad infrastructure. The results of this study indicate that (1) the higher the performance grade (PG), the higher the indirect tensile strength (ITS) value achieved by the 13 mm mixture using PG76-22, which is higher than that of the PG64-22 mixture. This indicates that higher PG grades and modification contribute to improved tensile strength, beneficial for upper layers subjected to dynamic railroad loads. (2) The tensile strength ratio (TSR) increased from the unmodified mixture to over 92% in mixtures containing crumb rubber modifier (CRM) and styrenic thermoplastic elastomer (STE), demonstrating enhanced durability under freeze-thaw conditions. (3) Wheel tracking test results showed that modified mixtures exhibited more than twice the rutting resistance compared to PG64-22. The 13 mm aggregate mixtures also generally performed better than the 19 mm mixtures, indicating reduced permanent deformation under repeated loading. (4) It was concluded that asphalt is a suitable material for railroads, as its overall characteristics comply with standard specifications.
The synergistic strategy for fine particulate matter (PM2.5) and O3 pollution prevention and control has emerged as a pivotal approach in combating air pollution. Volatile organic compounds (VOCs) serve as crucial precursors to both O3 and secondary organic aerosols (SOAs), with motor vehicles representing one of their significant sources. In this study, a standard for establishing a database of VOC species emission factors for motor vehicles was developed, and a database containing 134 VOC species was constructed through field tests and literature surveys. The VOC emissions of light-duty gasoline passenger vehicles (LDGPVs) comprised primarily alkanes and aromatics. The VOC emissions of light-duty diesel trucks (LDDTs) comprised mostly alkanes. Regarding low-speed trucks, 3-wheel vehicles, medium-duty diesel trucks (MDDTs) and heavy-duty diesel trucks (HDDTs), their VOC emissions comprised mainly oxygenated volatile organic compounds (OVOCs). The update of emission standards resulted in a reduction in VOC species emission factors while altering the composition of VOCs. Attention should be directed toward isopentane, benzene and dichloromethane emitted by LDGPVs, dodecane, undecane, ethene and propene emitted by LDDTs, and acetaldehyde emitted by HDDTs. VOC species originating from LDGPVs were more dispersed than those originating from LDDTs and HDDTs. In addition, variations in VOC species were observed among motor vehicles with different fuel types. Toluene, ethene, benzene, m,p-xylene, isopentane, hexanal, ethyne and 1,2,4-trimethylbenzene were the predominant VOC species emitted by gasoline vehicles. Diesel vehicles emitted mainly dodecane, formaldehyde, propene, undecane, acetaldehyde, ethene, decane and benzene. The results could enhance our comprehension of the emission characteristics of VOC species originating from motor vehicles and provide data support and a scientific foundation for achieving synergistic PM2.5 and O3 pollution prevention and control.
Implementation of evidence-based approaches to reduce the substantial health, social, and financial burdens of road traffic injuries and deaths in Ghana and other low-and-middle-income countries (LMICs) is vitally important. Consensus from national stakeholders can provide insight into what evidence to generate and which interventions to prioritize for road safety. The main objective of this study was to elicit expert views on the barriers to reaching international and national road safety targets, the gaps in national-level research, implementation, and evaluation, and the future action priorities. We used an iterative three-round modified Delphi process to generate consensus among Ghanaian road safety stakeholders. We defined consensus as 70% or more stakeholders selecting a specific response in the survey. We defined partial consensus (termed "majority") as 50% or more stakeholders selecting a particular response. Twenty-three stakeholders from different sectors participated. Experts generated consensus on barriers to road safety goals, including the poor regulation of commercial and public transport vehicles and limited use of technology to monitor and enforce traffic behaviors and laws. Stakeholders agreed that the impact of increasing motorcycle (2- and 3-wheel) use on road traffic injury burden is poorly understood and that it is a priority to evaluate road-user risk factors such as speed, helmet use, driving skills, and distracted driving. One emerging area was the impact of unattended/disabled vehicles along roadways. There was consensus on the need for additional research, implementation, and evaluation efforts of several interventions, including focused treatment of hazardous spots, driver training, road safety education as part of academic curricula, promotion of community involvement in first aid, development of strategically positioned trauma centers, and towing of disabled vehicles. This modified Delphi process with stakeholders from Ghana generated consensus on road safety research, implementation, and evaluation priorities.
Road traffic injury has long been regarded as a "time-dependent disease." However, shortening the prehospital time might not improve the outcome in developing countries given the current quality of in-hospital care. We aimed to examine the relationship between the prehospital time and 24-h mortality among road traffic victims in Laos. A prospective observational study was conducted using the trauma registry data on traffic-injured patients who were transported by ambulance to a trauma center in the capital city of Laos from May 2018 to April 2019. The analysis focused on patients with non-mild conditions, whose outcomes could be affected by the prehospital time. To examine the relationship between a prehospital time of <60 min and 24-h mortality, a generalized estimating equation model was used incorporating the inverse probability weights utilizing the propensity score for the prehospital time. Of 701 patients, 73% were men, 91% were riding 2- or 3-wheel motor vehicles during the crash, and 68% had a prehospital time of <60 min. A total of 35 patients died within 24 h after the crash. Compared with those who survived, individuals who died tended to have head and torso injuries. The proportions of 24-h mortality were 4.7% and 5.4% in patients whose prehospital time was <60 min and ≥60 min, respectively. No significant relationship was found between the prehospital time and 24-h mortality. A shorter prehospital time was not associated with the 24-h survival among road traffic victims in Laos.
Vehicle exhaust from traffic is a widespread air pollutant. The use of 3-wheel auto-rickshaws powered by a 2-stroke engine is widespread in south Asia; exhaust from these vehicles may cause different types of toxicities resulting in different pathologies. The aim of this study was to explore the association between exposure to 2-stroke auto-rickshaw smoke solution (2SARSS) and wound healing. The in vivo model of wound healing was customized to evaluate different stages of wound healing: dermal matrix regeneration, re-epithelialization, and neovascularization. A total of 72 adult mice were divided into 8 groups and exposed to 2SARSS for 12 days. A highly significant reduction (p<0.001) in wound closure was observed among all 2SARSS-treated groups at day 8 post-wounding. Histological examination revealed a significant delay in the outcome of re-epithelialization, dermal matrix regeneration, and maturation of collagen bundles among all 2SARSS-exposed wounds. Delayed activation of neovascularization was seen in the 2SARSS-treated groups at day 12 post-wounding. The Abbot curve, angular spectrum, and several other 3D surface parameters of reverse wound topographies revealed a highly significant reduction (p<0.001) in angiogenesis. These results demonstrate that application of 2SARSS causes a substantial delay in the progression of angiogenesis, resulting in delayed onset of wound healing. These observations validate the damaging effects of 2SARSS on wound healing. Thus, people who are directly or indirectly exposed to this toxic exhaust are expected to have delayed wound healing, which could result in chronic wounds.
All terrain vehicles (ATVs) are a popular form of transportation and recreation for youth. ATVs are also convenient for farm-related activities. However, the impact of the farming environment on ATV-related injuries is not clear. To determine differences in ATV-related behaviors, exposures, risk factors, and injuries between farm youth and their nonfarm peers. A cross-sectional study design was used. A survey was administered to 652 youths in agricultural education programs throughout the state of Arkansas. A majority (60%) of students have operated ATVs within the past month. Cross tabulations found that farm youth who rode ATVs were more likely to be white and male, to own a 3-wheel ATV, and to ride more often with a single rider. Risk factors for sustaining an ATV-related injury were frequency of use and the number of persons on the ATV. Study findings suggest that ATV use among farm youth does differ from their nonfarm peers. ATV use among all youth is a safety concern in Arkansas because of the behaviors and exposures that the youth cited.
To quantify levels of torso muscular demand during wheelchair ramp ascent and the ability of a geared wheel to influence trunk muscle activity. Repeated-measures design. Each participant completed manual wheelchair ramp ascents for each combination of 4 ramp grades (1:12, 1:10, 1:8, and 1:6) and 3 wheel conditions (in gear, out of gear, and a standard spoked wheel) in a block randomized order by wheel condition. Biomechanics laboratory. Healthy novice wheelchair users (N=13; 6 men) from a university student population. Not applicable. Peak electromyographic activity, expressed as a percentage of maximal voluntary isometric contraction (MVIC) of the abdominals, latissimus dorsi, and erector spinae during ramp ascent. Temporal location of peak electromyographic activity (EMG) within a propulsive cycle and integrated electromyographic activity for a single propulsive cycle. Abdominal peak activity increased 13.9% MVIC while peak posterior trunk muscle activity increased 4.9% MVIC between the shallowest and steepest ramp grades (P<.05). The geared wheel prevented increased peak activity of the rectus abdominis and external oblique (P>.05). Only peak electromyographic timing of the erector spinae was influenced during the push phase by increasing ramp slope. Increased trunk muscular demand as a result of increasing ramp slope is required to enhance stiffness of the spinal column and provide a stable base during manual propulsion. Manual wheelchair users with compromised activity capacity, compromised abdominal muscle strength, or both, may be able to navigate more difficult terrains while using a geared wheelchair wheel because of reduced demands from the abdominal musculature in the geared wheel condition.
Morbidity and mortality from pediatric head injuries associated with the use of off-road vehicles are increasing. We reviewed all such injuries admitted to acute care hospitals in the two largest urban centers in Manitoba between April 1979 and August 1986. Of 375 injured children, 83 suffered head injury, 70 boys and 13 girls. Ages ranged from 2 to 15 years, with a mean of 10.4 years. Head injury was defined as any injury involving face, scalp or nervous system. Dirtbikes were implicated in 34 accidents, snowmobiles in 28, 3-wheel ATV's in 19, and 4-wheel ATV's in 2. About 85% of accidents occurred in a rural setting. Loss of vehicle control was the most common cause of injury. Alcohol or drug abuse were not factors. Fifty (60.2%) patients suffered loss of consciousness, prolonged in 6 (7.2%). All head-injured children also suffered at least one associated injury, mainly involving the musculoskeletal system. Associated spinal injury occurred in 18%. The average hospital stay was 13 days. Three (3.6%) patients died as a result of head injury.
Current anti-migraine treatments have limited efficacy and many side effects. Although anecdotal evidence suggests that marijuana is useful for migraine, this hypothesis has not been tested in a controlled experiment. Thus, the present study tested whether administration of ∆9-tetrahydrocannabinol (THC) produces anti-migraine effects in the female rat. Microinjection of the TRPA1 agonist allyl isothiocyanate (AITC) onto the dura mater produced migraine-like pain for 3h as measured by depression of home cage wheel running. Concurrent systemic administration of 0.32 but not 0.1mg/kg of THC prevented AITC-induced depression of wheel running. However, 0.32mg/kg was ineffective when administered 90min after AITC. Administration of a higher dose of THC (1.0mg/kg) depressed wheel running whether rats were injected with AITC or not. Administration of a CB1, but not a CB2, receptor antagonist attenuated the anti-migraine effect of THC. These data suggest that: 1) THC reduces migraine-like pain when administered at the right dose (0.32mg/kg) and time (immediately after AITC); 2) THC's anti-migraine effect is mediated by CB1 receptors; and 3) Wheel running is an effective method to assess migraine treatments because only treatments producing antinociception without disruptive side effects will restore normal activity. These findings support anecdotal evidence for the use of cannabinoids as a treatment for migraine in humans and implicate the CB1 receptor as a therapeutic target for migraine.
Cancer has been shown to negatively stimulate autophagy, leading to a decline in cardiac function. Although exercise is cardioprotective, its influence over autophagy-mediated tumor growth and cardiac function are not well defined. This study aimed to determine the effect of exercise on tumor morphology and cardiac function. Fisher 344 rats (n = 28) were assigned to one of four groups: 1) sedentary non-tumor bearing (SED), 2) sedentary tumor bearing (SED + T), 3) wheel run non-tumor bearing (WR), or 4) wheel run tumor bearing (WR + T). Rats remained sedentary or exercised for 6 wk. At week 4, rats in tumor groups were inoculated with MatBIII tumor cells. At week 6, cardiac function was measured. SED + T animals exhibited significantly lower left ventricular developed pressure when compared with SED, WR, and WR + T (P < 0.05). This coincided with a significant increase in cardiac autophagy (increased LC3-II) in SED + T animals when compared with SED, WR, and WR + T (P < 0.05). Furthermore, SED + T hearts showed a significant increase in β-myosin heavy chain expression versus nontumor groups (P < 0.05). Tumor mass was significantly larger (P < 0.001) in SED + T animals when compared with WR + T animals, which was accompanied by a significant increase in tumor LC3-II protein expression (P < 0.05). Nonexercised tumor-bearing rats showed severe cardiac dysfunction and excessive, maladaptive autophagy in the heart and tumors. Voluntary exercise preserved cardiac function and attenuated the autophagic response in heart and tumor tissues. This preservation may be related to the reduced tumor growth in aerobically exercised rats, to the improved regulation of autophagy by exercise, or both.
Two expeditions, two spacewalks, 322 days in space
A distant galaxy nicknamed Shadow Blaster may have revealed a surprising source of cosmic neutrinos: extreme star formation instead of a supermassive black hole。 The discovery suggests that hidden, dust-filled starburst galaxies could account for a significant fraction of the Universe’s high-energy neutrinos
Crypto Clipper spreads over USB and communicates over Tor
A new nature-inspired membrane uses perfectly uniform one-nanometer pores to filter molecules with remarkable precision。 The technology could transform industries such as pharmaceuticals and textiles by reducing energy consumption, improving water reuse, and delivering separation performance far beyond current filters
The mysterious Amaterasu particle may not be a proton at all。 New research suggests that some of the most extreme cosmic rays could be ultraheavy atomic nuclei, heavier than iron, which are better able to retain their energy while traveling through space。 This idea could help explain how these rare particles reach Earth and provide new clues about