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Latent fingerprints (LFPs) is one of the most important physical evidence in the criminal scene, playing an important role in forensic investigations. Therefore, developing highly sensitive and convenient materials for the visualization of LFPs is of great significance. We designed and synthesized an organic fluorescent molecule TP-PH with aggregation-induced enhanced emission (AIEE) activity. By simply soaking, blue fluorescent images with high contrast and resolution are readily developed on various surfaces including tinfoil, steel, glass and plastic. Remarkably, LFPs can be visualized within 5 min including the first-, second- and tertiary-level details. In addition, TP-PH exhibits interesting photoactivated fluorescence enhancement properties. Under irradiation of 365 nm UV light with a power density of 382 mW/cm2, the fluorescence quantum yield displays approximately 21.5-fold enhancement. Mechanism studies reveals that the photoactivated fluorescence is attributed to the irreversible cyclodehydrogenation reactions under UV irradiation. This work provides a guideline for the design of multifunctional AIEE fluorescent materials.
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OBJECTIVE: To investigate the effects of low-dose S-ketamine on marker of myocardial injury (BNP, hs-cTnT and HFABP) after thoracoscopic lobectomy in patients aged 70 to 85. METHODS: One hundred patients (four cases excluded) aged 70-85 years, with body mass index 18-24 kg·m-2 and American Society of Anesthesiologists physical status II-III, scheduled for elective lobectomy from April 2022 to April 2023, were selected. The patients were divided into two groups by a random number table method, namely, the low-dose S-ketamine combined with GDFT group (group S) and the control group (group C), with 48 cases in each group. In group S, a low dose of S-ketamine (0.2 mg/kg) was given 1 min before intubation, and the maintenance dose was 0.12 mg·kg-1·h-1. Fluid therapy, guided by cardiac index (CI), changes in stroke volume (â³SV), and other dynamic indicators, was used for rehydration during the operation. Group C was given the same amount of normal saline (0.2 mg/kg) 1 min before intubation, and the same rehydration therapy was adopted during the operation. The mean arterial pressure (MAP) and heart rate (HR) of the two groups were observed and recorded immediately after entering the operating room (T0), immediately after intubation (T1), immediately after the beginning of one-lung ventilation (OLV) (T2), immediately after the beginning of surgery (T3), immediately after the end of OLV (T4), and at the end of surgery (T5). The intraoperative fluid intake and output and the use of vasoactive drugs were recorded. The plasma levels of heart-type fatty acid-binding protein (HFABP), high-sensitivity troponin T (hs-cTnT), brain natriuretic peptide (BNP), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) were recorded 24 h before operation and 24 and 48 h after operation. Visual analogue scale (VAS) pain scores at rest were recorded at 2 (V1), 6 (V2), 12 (V3), 24 (V4), and 48 h (V5) after operation, and the occurrence of myocardial ischemia during hospitalization was noted. RESULTS: Compared with group C, MAP was significantly higher at T1-T5 in group S (P < 0.05), and the plasma concentrations of IL-6, IL-8, TNF-α, BNP, hs-cTnT, and HFABP were significantly lower at 24 and 48 h after operation (P < 0.05). The VAS pain scores at 2, 6, 12, 24, and 48 h after operation, the number of effective patient-controlled intravenous analgesia (PCIA) compressions, and the total number of PCIA compressions within 48 h after operation were significantly decreased (P < 0.05). Compared with group C, The hospitalization days, and the incidence of postoperative myocardial ischemia in group S were lower (P < 0.05). There were no significant intergroup differences in urine volume, extubation time, the incidence of postoperative atrial fibrillation, bleeding volume, colloid infusion volume, total fluid infusion volume, and the incidence of rescue analgesia. CONCLUSIONS: Low-dose S-ketamine can reduce the levels of hs-cTnT, HFABP, and BNP in older patients after pulmonary lobectomy, which has a positive effect on preventing myocardial injury. TRIAL REGISTRATION: This study was registered on CHICTR (registration No. ChiCTR2300074475). Date of registration: 08/08/2023.
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Interleucina-8 , Ketamina , Isquemia Miocárdica , Humanos , Idoso , Interleucina-6 , Fator de Necrose Tumoral alfa , Analgesia Controlada pelo Paciente , Dor , Isquemia Miocárdica/prevenção & controleRESUMO
The toxicity of arsenic (As) targets specific tissues of organisms, while the biotransportation of As among the tissues of fish remains poorly understood. In the present study, radiotracer techniques followed by a physiologically based pharmacokinetic (PBPK) modeling were applied to simulate the biotransportation (absorption, distribution, and elimination) of 73As(V) and biotransformation of As(V) in the marine medaka Oryzias melastigma after waterborne As exposure. Fish were simulated by a six-compartment model by assuming that blood was the intermediate exchange among different compartments (gill, intestine, liver, head, and carcass). Modeling suggested that intestine and gill were the uptake, exchange, as well as elimination sites of waterborne As, while carcass and head were the main storage sites. Intestine played a vital role in the metabolism of As(V) by biotransforming inorganic As into arsenobetaine (AsB), possibly because of the important role of gut microbiota. The correlation between the PBPK model constants and the As speciation (e.g., AsB %, inorganic As %, and methylated As %) indicated that AsB tended to be stored in the tissues rather than being depurated, while inorganic and methylated As were more easily transferred from tissues to the blood and eliminated. Modeling simulation coupling with biotransformation for the first time demonstrated that the fish intestine was the main metabolic site, and synthesis of AsB as mediated by the microbiota in the intestine contributed to the high As bioaccumulation in marine fish.
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Arsênio , Oryzias , Poluentes Químicos da Água , Animais , Biotransformação , BrânquiasRESUMO
Three Ir(Câ§N)2(acac)-type and one Ir(C1â§N)(C2â§N)(acac)-type coumarin-based cyclometalated Ir(III) complex isomers (IrC5, IrC7, IrC7-A, and IrC8) have been obtained using three coumarin-based isomers of 2-phenylpyridine (ppy)-type cyclometalating ligands (L-C5, L-C7, and L-C8). Two coordination isomers emerging as principal products (IrC7 and IrC7-A) are obtained in the synthesis of corresponding coumarin-based cyclometalated Ir(III) complexes because of two different coordination sites in ligand L-C7 to form a C-Ir bond. To the best of our knowledge, there are no such isomers reported to date. Interestingly, a broad range of phosphorescent color tuning from green (IrC8, λ = 516 nm) to red (IrC5, λ = 608 nm) has been realized through variation of the pyridyl substitution positions on the fused phenyl ring of the coumarin skeleton. In addition, based on natural transition orbital (NTO) analyses, features of the lowest triplet excited states (T1) from these coumarin-based cyclometalated Ir(III) complex isomers can be tuned easily by these ligand isomers as well. IrC5, IrC7, and IrC7-A show prevailing 3MLCT character associated with their T1 states which emit the phosphorescent signals, while the T1 state of IrC8 exhibits the dominant ligand-centered π-π* transition feature. Importantly, owing to the strong rigidity of the coumarin skeleton, all the coumarin-based cyclometalated Ir(III) complex isomers can show high phosphorescent quantum yields Φp (ca. 0.4-1). Together with the improved electron-injection/electron-transport (EI/ET) ability, all the phosphorescent emitters display impressive electroluminescence (EL) performance. The device based on IrC8 gives the highest EL efficiencies of external quantum efficiency (ηext) 22.7%, current efficiency (ηL) 79.7 cd A-1, and power efficiency (ηP) 58.2 lm W-1, representing the most state-of-the-art EL ability ever achieved by coumarin-based phosphorescent emitters. All these encouraging data definitely suggest the great potential of the coumarin skeleton in both easy tuning of the photophysical properties of ppy-type Ir(III) phosphorescent complexes and developing high-performance phosphorescent emitters.
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OBJECTIVE: To explore the clinical features, neuroimaging and histopathological findings in patients with idiopathic hypertrophic cranial pachymeningitis (IHCP) with a nodular space occupying effect. METHODS: Four IHCP cases with a nodular space occupying effect diagnosed in our hospital were retrospectively studied. RESULTS: All the 4 patients were men with a mean onset age of 40.25 (33 â¼ 50) years old. They all had long disease duration and relapses. The common symptoms of IHCP were chronic headache, multiple cranial nerve palsies and epileptic seizures. CT and MRI of the brain revealed prominent dural partial thickening, which indicated a mass or nodular space occupying effect that mimicked intracranial tumour-like meningioma. The histopathological findings of dura in 2 cases revealed connective tissue proliferation, scattered neutrophil granulocytes and plasmacytes infiltration. Combination therapy of corticosteroid or/and immunosuppressive drugs was effective for the IHCP patients. CONCLUSIONS: IHCP patients with a nodular space occupying effect usually onset with chronic headache and are often recurrent. The combination therapy of corticosteroid or/and immunosuppressive drugs is effective. The image of the brain presents prominent dural partial thickening, indicating a mass or nodular space occupying effect, which often lead to confusion with intracranial tumours or granulomatosis.
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Meningite/diagnóstico , Meningite/patologia , Adulto , Diagnóstico por Imagem , Humanos , Hipertrofia/tratamento farmacológico , Hipertrofia/patologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Changes in heart structure and function after lung resection in patients with lung cancer are challenging to manage. Therefore, a non-invasive and reliable measurement tool to gauge such changes is critical. The purpose of the present study was to compare cardiological changes before and after lung resection using tissue Doppler imaging (TDI). A total of 43 patients (19 men and 24 women) with primary non-small cell lung cancer (n=37) and metastatic cancer in the lungs (n=6) were enrolled in the study.nTDI was used to determine the thickness of the ascending aorta, the open size of the ascending valve, the anterior-oposterior diameters of the left atrium and left ventricle, and the thickness of the ventricular septum and right ventricle before and after lung resection. Left ventricular (LV) ejection fraction (EF), pulmonary valve flow rate, tricuspid annular or mitral leaflet tip early (E) peak/late (A) diastolic blood flow velocities, tricuspid regurgitation flow, the lateral mitral annulus early (e') diastolic velocity and mitral E/e' ratio were used to determine LV filling pressure. Results revealed no significant differences between male and female patients in terms of the open size of the ascending valve, the anterior-posterior diameter of the left ventricle and the mitral E/e' ratio. Significant differences were found in the width of the ascending aorta, anterior-posterior diameter of the left atrium, width of the LV septum and right ventricular (RV) diameter before and after lung resection. Finally, there were significantchanges in EF and tricuspid pressure. The results indicated that TDI was useful as a non-invasive method for assessing left and right heart function following lung resection. The LV and RV dimensions were affected, but LV filling pressure was preserved after lobectomy.
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Pinch milling is a new technique for slender and long blade machining, which can simultaneously improve the machining quality and efficiency. However, two-cutter orientation planning is a major challenge due to the irregular blade surfaces and the structural constraints of nine-axis machine tools. In this paper, a method of twin-tool smoothing orientation determination is proposed for a thin-walled blade with pinch milling. Considering the processing status of the two cutters and workpiece, the feasible domain of the twin-tool axis vector and its characterization method are defined. At the same time, an evaluation algorithm of global and local optimization is proposed, and a smoothing algorithm is explored within the feasible domain along the two tool paths. Finally, a set of smoothly aligned tool orientations are generated, and the overall smoothness is nearly globally optimized. A preliminary simulation verification of the proposed algorithm is conducted on a turbine blade model and the planning tool orientation is found to be stable, smooth, and well formed, which avoids collision interference and ultimately improves the machining accuracy of the blade with difficult-to-machine materials.
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The presence of unobserved factors in the motorcycle involved two-vehicle crashes (MV) data could lead to heterogenous associations between observed factors and injury severity sustained by motorcyclists. Capturing such heterogeneities necessitates distinct methodological approaches, of which random and scale heterogeneity models are paramount. Herein, we undertake an empirical evaluation of random and scale heterogeneity models, exploring their efficacy in delineating the influence of external determinants on the degree of injury severity in crashes. Within the effects of scale heterogeneity, this study delves into two dominant models: the scaled multinomial logit model (S-MNL) and its generalized counterpart, the G-MNL, which encompasses both the S-MNL and the random parameters multinomial logit model (RPL). While the random heterogeneity domain is represented by the random parameters multinomial logit and an upgraded variant - the random parameters multinomial logit model with heterogeneity in means and variances (RPLHMV). Motorcycle involved two-vehicle crashes data were extracted from the UK STATS19 dataset from 2016 to 2020. Likelihood ratio tests are computed to assess the temporal variability of the significant factors. The test result demonstrates the temporal variations over a five-year study period. Some very important differences started to show up across the years based on the model estimation results: that the RPLHMV model statistically outperforms the G-MNL model in the 2016, 2018, and 2019 models, while the S-MNL model is statistically superior in the 2017 and 2020 years. These important findings suggest that the origin of heterogeneity in explaining factor weights can be captured by scale effects, not just random heterogeneity. In addition, the model results further show that motorcyclists' injury severities are significantly affected by motorcycle-related characteristics; there is the added factor of external influences, such as non-motorcycle drivers (males, young drivers, and elderly drivers) and vehicles (the moving status, age, and types of vehicles) that collide with motorcycles. The results of this paper are anticipated to help policymakers develop effective strategies to mitigate motorcycle involved two-vehicle crashes by implementing appropriate measures.
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Acidentes de Trânsito , Ferimentos e Lesões , Idoso , Humanos , Masculino , Funções Verossimilhança , Modelos Logísticos , Motocicletas , FemininoRESUMO
In high-temperature drilling, especially in high-temperature geothermal drilling, cone bits often experience common and severe tooth loss. This issue significantly reduces the cone bit's service life and has a detrimental impact on drilling efficiency. The quality of the fixed teeth plays a crucial role in the performance of the cone bit. In high-temperature environments, conventional methods fail to meet the requirements for securing the cone bit's teeth. Therefore, to address the tooth loss problem in high-temperature drilling, a new tapered tooth structure is proposed. Laboratory experiments were conducted to secure teeth with varying tapers at both normal and high temperatures. The results revealed that the maximum fastening force increased progressively with the degree of taper, reaching its peak at C50. Compared to conventional cylindrical teeth, the maximum fastening force increased by approximately 88.6%-271.1% at different temperatures. The tapered structure demonstrated superior tooth-fixing strength. The maximum fastening force is the smallest at 300â °C, approximately 23.7%-61.2% lower than at normal temperature. Under the same interference conditions, the maximum fastening force increased with greater taper. With interference values of 0.075, 0.095, and 0.115, the maximum fastening force increased by 48.9%-175.1%, 14%-141.6%, and 53%-271.1%, respectively, when compared to cylindrical teeth with C300, C200, C100, and C50 tapers. The tapered structure exhibited superior tooth-fixing strength and significantly enhanced tooth retention strength at high temperatures.
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BACKGROUND: Video-assisted thoracoscopic (VATS) lobectomy can affect patients' pulmonary function and quality of life significantly. No optimal protocol combining patient-reported outcome-based symptom management and post-discharge rehabilitation programme has yet been established. This study aimed to assess the efficacy of a novel smartphone app designed for home-based symptom management and rehabilitation. METHODS: The app was developed based on three modules: a symptom reporting system with alerts, aerobic and respiratory training exercises, and educational material. Four core symptoms were selected based on a questionnaire survey of 201 patients and three rounds of Delphi voting by 30 experts. We screened 265 patients and randomly assigned 136 equally to the app group and usual care group. The primary outcome was pulmonary function recovery at 30 days postoperatively. Secondary outcomes included symptom burden and interference with daily living (both rated using the MD Anderson Symptom Inventory for Lung Cancer), aerobic exercise intensity, emergency department visits, app-related safety, and satisfaction with the app. FINDINGS: Of the 136 participants, 56.6% were women and their mean age was 61 years. The pulmonary function recovery ratio 1 month after surgery in the app group was significantly higher than that in the usual care group (79.32% vs. 75.73%; P=0.040). The app group also recorded significantly lower symptom burden and interference with daily living scores and higher aerobic exercise intensity after surgery than the usual care group. Thirty-two alerts were triggered in the app group. The highest pulmonary function recovery ratio and aerobic exercise intensity were recorded in those patients who triggered alerts in both groups. INTERPRETATION: Using a smartphone app is an effective approach to accelerate home-based rehabilitation after VATS lobectomy. The symptom alert mechanism of this app could optimise recovery outcomes, possibly driven by patients' increased self-awareness.
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OBJECTIVE: To evaluate the diagnostic value of external anal sphincter electromyography (EAS-EMG) versus urethral sphincter electromyography (US-EMG) in patients with multiple system atrophy (MSA). METHODS: A total of 27 MSA patients were examined with EAS and US-EMG as treatment group while 28 non-MSA subjects as control group. Spontaneous activities during relaxation, mean duration & amplitude of motor unit potential (MUP), percentage of polyphasic and variations during strong contraction were recorded and analyzed statistically. RESULTS: There was significant difference in light contraction between MSA and non-MSA cases on both EAS-EMG and US-EMG (EAS-EMG, P < 0.001; US-EMG, P = 0.002) . Meanwhile, strong contraction and percentage of polyphasic showed significant differences between MSA and non-MSA cases on EAS-EMG only (strong contraction, P = 0.016; percentage of polyphasic, P = 0.004) . EAS-EMG showed more significant changes in neurogenic injury than US-EMG. CONCLUSIONS: US-EMG and EAS-EMG are valuable for the diagnosis of MSA. The differences of multiple parameters of EAS-EMG were more significant than those of US-EMG for MSA cases. US-EMG may serve as a supplement of EAS-EMG in case of restriction.
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Canal Anal/fisiopatologia , Eletromiografia/métodos , Atrofia de Múltiplos Sistemas/diagnóstico , Atrofia de Múltiplos Sistemas/fisiopatologia , Uretra/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To explore the cognitive function, emotional status and activities of daily living in patients with multiple system atrophy (MSA). METHODS: Thirty-two MSA patients and 38 healthy controls from October 2009 to November 2012 were recruited from our hospital. Their cognitive function, emotional status and activities of daily living were assessed. Cognitive function was assessed by Montreal cognitive assessment (MoCA) and mini-mental state examination (MMSE); emotional status by self-rating depression scale (SDS) and self-rating anxiety scale (SAS); daily living and activities by activities of daily living scale (ADL). Data analysis was performed with SPSS 19.0. And the results were presented as the mean ± standard deviation. Comparison of means was performed with independent sample t test. And Pearson's correlation test was used for correlation analysis. A P-value <0.05 was considered significant. RESULTS: Mild or moderate cognitive impairment was documented in 71.9% of MSA patients. The scores of MoCA and MMSE in the MSA group were significantly lower than those in the control group. And the scores of ADL, SDS and SAS in the MSA group were significantly higher than those in the control group (P < 0.05). MoCA subitems such as space/executive function, attention, abstraction, language and delayed memory of the MSA group were significantly lower than those of the control group (P < 0.05). A negative correlation existed between the scores of MoCA and MMSE with disease duration (P < 0.01). There was a positive correlation between the scores of SDS and SAS with ADL and disease duration (P < 0.05). And the relationship was significant between the scores of SDS and SAS (P < 0.01). A positive correlation existed between scores of ADL with disease duration (P < 0.05). CONCLUSION: MSA patients have certain degrees of cognitive impairment, emotion disorders and impaired ADL. Cognitive impairment in MSA patients may be more common than previously. Furthermore, the clinical features of cognitive impairment in these patients may have some clinical values for references.
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Atividades Cotidianas , Afeto , Cognição , Atrofia de Múltiplos Sistemas/psicologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes NeuropsicológicosRESUMO
This paper aims to empirically evaluate the ordered and unordered discrete outcome frameworks to approach riders' red-light running (RLR) decisions and compare the differences in influencing factors between riders' risk-taking and opportunistic RLR behaviors. A total of 2057 cyclist samples approaching the intersections during red signals were observed by video in Beijing, China. To better capture the unobserved heterogeneity, apart from the traditional models, three advanced models including the random thresholds random parameters hierarchical ordered logit (RTRPHOL) model, the random parameters logit model with heterogeneity in means and variances (RPLHMV) model, and the correlated random parameters logit model with heterogeneity in means (CRPLHM), are developed. Results show that: 1) the unordered framework statistically outperformed its ordered counterparts, and the RPLHMV and CRPLHM models are statistically better than others. 2) The female and e-bicycle indicators produce a heterogeneity-in-means effect, and the low-volume and left-side indicators produce a heterogeneity-in-variances effect. 3) e-bike riders and riders from the right side are more inclined to have risk-taking behavior than opportunistic behavior, and both RLR behaviors of cyclists are most susceptible to the number of violating individual indicator. Findings illustrate that multilayer unobserved heterogeneity should be adequately considered in developing precise micro-simulation and practical guidance in traffic safety.
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Acidentes de Trânsito , Assunção de Riscos , Humanos , Feminino , Ciclismo , Luz , China , Modelos LogísticosRESUMO
BACKGROUND: Existing studies mainly focus on the relationship between real-time weather and traffic crash injury severity, while few scholars have investigated the operation risk levels caused by traffic incidents. Identifying weather-related factors that affect the incident-induced delay is helpful for estimating the delay levels when an incident occurs. Accordingly, the present study profoundly explores the relationship between weather conditions and traffic delays caused by traffic incidents. METHODS: The traffic incident and weather datasets from January 1 to December 31, 2020, in New York State are used. To that end, the hazard-based duration and multinomial logit modeling frameworks are employed to determine the effect of weather conditions on the duration of traffic delay and the delay severity, respectively. More importantly, to account for multiple layers of unobserved heterogeneity, a random parameter with heterogeneity in means approach is introduced into the above two models. RESULTS: (1) The strong breeze (wind speed over 8 m/s) and low visibility (visibility under 5 km) significantly affect the duration of delay. (2) Hot day (between 20 and 30 °C) has a 344.03 % greater probability of minor delay. A strong breeze has a higher probability of severe delay. The low visibility is found to increase the estimated odds of moderate delay and severe delay by 51.15 % and 13.39 %, respectively. In comparison, the normal visibility (between 10 and 20 km) significantly decreases the estimated odds of severe delay by 119.17 %. CONCLUSIONS: Compared with other weather factors, wind speed, temperature, and visibility have the greatest impact on the traffic delay levels after a traffic accident, and there are significant differences in the impact under different delay severity. Findings from this study will help policymakers to establish comprehensive differentiating security measures to resolve traffic delays.
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Truck-involved crashes, especially truck-car crashes, are associated with serious and even fatal injuries, thus necessitating an in-depth analysis. Prior research focused solely on examining the injury severity of truck drivers or developed separate performance models for truck and car drivers. However, the severity of injuries to both drivers in the same truck-car crash may be interrelated, and influencing factors of injury severities sustained by the two parties may differ. To address these concerns, a random parameter bivariate probit model with heterogeneity in means (RPBPHM) is applied to examine factors affecting the injury severity of both drivers in the same truck-car crash and how these factors change over the years. Using truck-car crash data from 2017 to 2019 in the UK, the dependent variable is defined as slight injury and serious injury or fatality. Factors such as driver, vehicle, road, and environmental characteristics are statistically analyzed in this study. According to the findings, the RPBPHM model demonstrated a remarkable statistical fit, and a positive correlation was observed between the two drivers' injury severity in truck-car crashes. More importantly, the effects of the explanatory factors showing relatively temporal stability vary across different types of vehicle crashes. For example, car driver improper actions and lane changing by trucks, have a significant interactive effect on the severity of injuries sustained by drivers involved collisions between trucks and cars. Male truck drivers, young truck drivers, older truck drivers, and truck drivers' improper actions, elevate the estimated odds of only truck drivers; while older car and unsignalized crossing increase the possibility of injury severity of only car drivers. Finally, due to shared unobserved crash-specific factors, the 30-mph speed limit, dark no lights, and head-on collision, significantly affect the severity of injuries sustained by drivers involved in collisions between trucks and cars. The modeling approach provides a novel framework for jointly analyzing truck-involved crash injury severities. The findings will help policymakers take the necessary actions to reduce truck-car crashes by implementing appropriate and accurate safety countermeasures.
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Automóveis , Ferimentos e Lesões , Masculino , Humanos , Acidentes de Trânsito , Veículos Automotores , Correlação de Dados , Ferimentos e Lesões/epidemiologia , Modelos LogísticosRESUMO
Distraction and overspeed behaviors are acknowledged as two significant contributors to single-vehicle motorcycle crashes, injuries and fatalities resulting from which are severe and critical issues in Pakistan. To explore the temporal instability and differences in the factors determining the injury severities between single-vehicle motorcycle crashes caused by distraction and overspeed behaviors, this study estimated two groups of random parameter logit models with heterogeneity in means and variances. Single-vehicle motorcycle crash data in Rawalpindi city between 2017 and 2019 was used for model estimation, and a wide variety of explanatory variables relating to the rider, roadways, environments, and temporal attributes was simulated in the models. The current study considered three possible crash injury severity outcomes: minor injury, severe injury and fatal injury. Likelihood ratio tests were conducted to explore the temporal instability and non-transferability. Marginal effects were also calculated to further reveal temporal instability of the variables. Except for several variables, the most significant factors reported temporal instability and non-transferability, manifested as the effects varied from year to year and across different crashes. Moreover, out-of-sample prediction was also implemented to capture temporal instability and non-transferability between distraction and overspeed crash observations. The non-transferability between motorcycle crashes caused by distraction and overspeed behaviors provides insights into developing differentiated countermeasures and policies targeted at preventing and mitigating single-vehicle motorcycle crashes caused by the two risk-taking behaviors.
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Acidentes de Trânsito , Ferimentos e Lesões , Humanos , Motocicletas , Fatores de Risco , Modelos Logísticos , PaquistãoRESUMO
The existing literature has confirmed that extreme weather such as wind, rain, and snow have a negative impact on cross-sectional traffic flow. However, travel activities with different destination regions, travel distances and vehicle types may have different responses to severe weather. We employ the multilevel mixed-effects negative binomial (MENB) model to explore the interaction effect of severe weather and non-weather factors on intercity origin-destination (OD) demand, based on the data from freeway toll stations in Shandong Province from March 2011 to February 2012. The MENB model is superior to the SNB model in that the former has both smaller AIC (456,645.4 < 4,586,877.2) and BIC (456,963.4 < 458,975.8) values and log-likelihood ratio tests. The results indicate that weather impact on freeway travel to the same metropolitan area is homogeneous, and the impact in different metropolitan areas is heterogeneous. Besides, there is an interaction effect between severe weather (strong wind, fog, heavy rain, snow) and travel distance on freeway OD volume. With increasing travel distance, the impact of both strong wind and heavy rain decreases gradually, while the impact of both fog and snow increases. In addition, heat (0.0351 > 0.0201), strong wind (0.0930 > 0.0454), and heavy rain (0.1245 > 0.1044) have a greater impact on passenger car volume than on truck volume, while fog (0.4340 < 0.4802) and snow (0.4383 < 0.4884) have a less significant impact on passenger car volume. The findings of this study provide some deep insights into the relationship between severe weather factors and intercity travel demand, which suggests that different strategies of travel demand management should be adopted for different travel distances and different vehicle types under various weather conditions.
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Acidentes de Trânsito , Tempo (Meteorologia) , Estudos Transversais , Veículos Automotores , NeveRESUMO
Aquatic organisms such as fish can accumulate high levels of arsenic (As) and transform toxic inorganic As (iAs) to non-toxic arsenobetaine (AsB). Whether the gut microbiota are involved in the process of As accumulation and transformation in fish is unclear. Herein, we subjected tilapia (Oreochromis mossambicus) to antibiotic treatment for 19 d to remove the gut microbiota, followed by the dietary exposure to arsenate (As(V)) for 16 d. The antibiotic-treated fish accumulated significantly less total As and AsB levels in the intestine and muscle than the fish in the control group. The gut contents (mixture of microbiota, digestive fluid, and diet debris) in the control fish metabolized As(V) to arsenite (As(III)) and organoarsenicals in vitro, while those in the antibiotic-treated fish lost this ability. As(V) exposure significantly changed the fish gut microbiota community. Stenotrophomonas maltophilia was found to be the dominant species (>60% of total operational taxonomic unit (OTU) number) in the gut microbiota of As-treated fish. The isolated As-resistant strain S. maltophilia SCSIOOM owned a high capability to metabolize As(V) to As(III) and organoarsenicals. Overall, these results demonstrated that the gut microbiota, at least the As-resistant bacteria, were involved in As biotransformation pathways in fish.
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Arsênio , Microbioma Gastrointestinal , Tilápia , Poluentes Químicos da Água , Animais , Antibacterianos/metabolismo , Arsênio/metabolismo , Bioacumulação , Biotransformação , Tilápia/metabolismo , Poluentes Químicos da Água/toxicidadeRESUMO
Carbon capture, utilization and storage (CCUS) has been applied in many countries and has proven to be a key carbon-reduction technology for the future. China currently emits the most carbon, and prior research findings indicate the high potential of CCUS technology to support the country's emission-reduction process. China introduced CCUS technology at the end of the 20th century and has since implemented a series of related policies. This paper compares the development status of CCUS in China and other countries, studies the legal and policy framework and the development process of CCUS in China, and analyzes the defects in relevant laws and policies. The results show that China's current legal and policy system is not conducive to the further development of CCUS; specifically, there is no special law, and the policy system is incomplete. Consequently, it is difficult to advance and give full play to the emission-reduction effect of CCUS. To promote CCUS development in China, this paper proposes corresponding countermeasures, including formulating a special law, perfecting the CCUS policy system, expanding government financial support, and improving CCUS public awareness and support.
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Carbono , Política de Planejamento Familiar , China , Política Pública , Dióxido de CarbonoRESUMO
Bacteria are candidates for the biotransformation of environmental arsenic (As), while As metabolism in bacteria is not yet fully understood. In this study, we sequenced the genome of an As-resistant bacterium strain Stenotrophomonas maltophilia SCSIOOM isolated from the fish gut. After arsenate (As(V)) exposure, S. maltophilia transformed As(V) to organoarsenicals, along with the significant change of the expression of 40 genes, including the upregulation of arsH, arsRBC and betIBA. The heterogeneous expression of arsH and arsRBC increased As resistance of E. coli AW3110 by increasing As efflux and transformation. E. coli AW3110 (pET-betIBA) could transform inorganic As into dimethylarsinate (DMA) and nontoxic arsenobetaine (AsB), which suggested that AsB could be synthesized through the synthetic pathway of its analog-glycine betaine. In addition, the existence of arsRBC, betIBA and arsH reduced the reactive oxygen species (ROS) induced by As exposure. In total, these results demonstrated that S. maltophilia adopted an As metabolism strategy by reducing As accumulation and synthesizing less toxic As species. We first reported the production and potential synthetic pathway of AsB in bacteria, which improved our knowledge of As toxicology in microorganisms.