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Vancomycin-resistant Enterococcus faecium (E. faecium) infection is associated with higher mortality rates. Previous studies have emphasized the importance of innate immune cells and signalling pathways in clearing E. faecium, but a comprehensive analysis of host-pathogen interactions is lacking. Here, we investigated the interplay of host and E. faecium in a murine model of septic peritonitis. Following injection with a sublethal dose, we observed significantly increased murine sepsis score and histological score, decreased weight and bacterial burden, neutrophils and macrophages infiltration, and comprehensive activation of cytokine-mediated signalling pathway. In mice receiving a lethal dose, hypothermia significantly improved survival, reduced bacterial burden, cytokines, and CD86 expression of MHC-II+ recruited macrophages compared to the normothermia group. A mathematical model constructed by observational data from 80 animals, recapitulated the host-pathogen interplay, and further verified the benefits of hypothermia. These findings indicate that E. faecium triggers a severe activation of cytokine-mediated signalling pathway, and hypothermia can improve outcomes by reducing bacterial burden and inflammation.
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Citocinas , Modelos Animales de Enfermedad , Enterococcus faecium , Infecciones por Bacterias Grampositivas , Interacciones Huésped-Patógeno , Peritonitis , Sepsis , Enterococos Resistentes a la Vancomicina , Animales , Peritonitis/microbiología , Peritonitis/inmunología , Ratones , Infecciones por Bacterias Grampositivas/inmunología , Infecciones por Bacterias Grampositivas/microbiología , Enterococos Resistentes a la Vancomicina/patogenicidad , Sepsis/microbiología , Sepsis/inmunología , Citocinas/metabolismo , Ratones Endogámicos C57BL , Macrófagos/inmunología , Macrófagos/microbiología , Transducción de SeñalRESUMEN
In winter snowy or rainy weather, the phenomenon of icing under rolling stock during high-speed operation is significantly severe, posing a potential risk of detachment and impact on track structures due to the presence of ice blocks with substantial mass and velocity. Therefore, it is crucial to develop an efficient method for characterizing and evaluating this impact damage in order to assess the service life of the track. To address this issue, the indoor ice impact tests were conducted on track slab models, and a comprehensive analysis was performed on non-destructive testing data before and after the impact test, including 3D surface morphology assessment, surface hardness and wave velocity measurements. Additionally, in order to verify the effectiveness of the nondestructive testing method, the frozen-thawed and not frozen-thawed track slab models were tested and their results were compared. The experimental results revealed that when impacted by ice blocks at a velocity of 100 m/s, small dimples formed on the surface of track slab models with the maximum depth measured at 0.0694 mm. There was a maximum increase rate in surface hardness amounting to 11.61%, and a maximum decrease rate in wave velocity measuring at 6.52%. Furthermore, the impact damage of the two models has been evaluated, the not frozen-thawed track slab model exhibited minor damage after impact, whereas the frozen-thawed track slab model demonstrated moderate damage in the contact region and minor damage outside of that region. The proposed non-destructive testing method effectively enables assessing the impact damage inflicted upon slab models while providing valuable insights for maintenance and repair strategies related to track slabs.
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The synergy between bacteria and fungi is a key determinant of soil health and have a positive effect on plant development under drought conditions, with the potentially enhancing the sustainability of amending soil with natural materials. However, identifying how soil amendments influence plant growth is often difficult due to the complexity of microorganisms and their links with different soil amendment types and environmental factors. To address this, we conducted a field experiment to examine the impact of soil amendments (biochar, Bacillus mucilaginosus, Bacillus subtilis and super absorbent polymer) on plant growth. We also assessed variations in microbial community, links between fungi and bacteria, and soil available nutrients, while exploring how the synergistic effects between fungus and bacteria influenced the response of soil amendments to plant growth. This study revealed that soil amendments reduced soil bacterial diversity but increased the proportion of the family Enterobacteriaceae, Nitrosomonadaceae, and also increased soil fungal diversity and the proportion of the sum of the family Lasiosphaeriaceae, Chaetomiaceae, Pleosporaceae. Changes in soil microbial communities lead to increase the complexity of microbial co-occurrence networks. Furthermore, this heightened network complexity enhanced the synergy of soil bacteria and fungi, supporting bacterial functions related to soil nutrient cycling, such as metabolic functions and genetic, environmental, and cellular processes. Hence, the BC and BS had 3.0-fold and 0.5-fold greater root length densities than CK and apple tree shoot growth were increased by 62.14 %,50.53 % relative to CK, respectively. In sum, our results suggest that the synergistic effect of bacteria and fungi impacted apple tree growth indirectly by modulating soil nutrient cycling. These findings offer a new strategy for enhancing the quality of arable land in arid and semi-arid regions.
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Microbiota , Suelo , Bacterias/metabolismo , Nutrientes , Hongos/metabolismo , Microbiología del SueloRESUMEN
BACKGROUND: Nosocomial infections caused by Serratia marcescens mostly occurred in pediatrics and it was very rarely reported after adult surgery. Here, an intracranial abscess caused by Serratia marcescens was reported. We report a rare case of a postoperative intracranial abscess caused by Serratia marcescens in a 63-year-old male patient with a left parietal mass. The patient underwent resection of the mass on June 1, 2022, and the postoperative pathology revealed an angiomatous meningioma, WHO I. He then experienced recurrent worsening of right limb movements, and repeated cranial CT scans showed oozing blood and obvious low-density shadows around the operation area. Delayed wound healing was considered. Subsequently, a large amount of pus was extracted from the wound. The etiological test showed that Serratia marcescens infection occurred before the removal of the artificial titanium mesh. Antibiotics were initiated based on the results of drug susceptibility tests. At present, the patient is recovering well and is still closely monitored during follow-up. CONCLUSION: It is rare for Serratia marcescens to cause brain abscesses without any obvious signs of infection. This report provided in detail our experience of a warning postoperative asymptomatic brain abscess caused by an uncommon pathogen.
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Absceso Encefálico , Infección Hospitalaria , Adulto , Masculino , Humanos , Niño , Persona de Mediana Edad , Serratia marcescens , Antibacterianos/uso terapéutico , Absceso Encefálico/diagnóstico , Periodo PosoperatorioRESUMEN
OBJECTIVE: This paper proposes an objective method to measure and identify trust-change directions during takeover transitions (TTs) in conditionally automated vehicles (AVs). BACKGROUND: Takeover requests (TORs) will be recurring events in conditionally automated driving that could undermine trust, and then lead to inappropriate reliance on conditionally AVs, such as misuse and disuse. METHOD: 34 drivers engaged in the non-driving-related task were involved in a sequence of takeover events in a driving simulator. The relationships and effects between drivers' physiological responses, takeover-related factors, and trust-change directions during TTs were explored by the combination of an unsupervised learning algorithm and statistical analyses. Furthermore, different typical machine learning methods were applied to establish recognition models of trust-change directions during TTs based on takeover-related factors and physiological parameters. RESULT: Combining the change values in the subjective trust rating and monitoring behavior before and after takeover can reliably measure trust-change directions during TTs. The statistical analysis results showed that physiological parameters (i.e., skin conductance and heart rate) during TTs are negatively linked with the trust-change directions. And drivers were more likely to increase trust during TTs when they were in longer TOR lead time, with more takeover frequencies, and dealing with the stationary vehicle scenario. More importantly, the F1-score of the random forest (RF) model is nearly 77.3%. CONCLUSION: The features investigated and the RF model developed can identify trust-change directions during TTs accurately. APPLICATION: Those findings can provide additional support for developing trust monitoring systems to mitigate both drivers' overtrust and undertrust in conditionally AVs.
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Conducción de Automóvil , Humanos , Confianza , Automatización , Proyectos de Investigación , Frecuencia Cardíaca , Accidentes de Tránsito , Tiempo de Reacción/fisiologíaRESUMEN
Pulmonary anthrax is the most fatal clinical form of anthrax and currently available injectable vaccines do not provide adequate protection against it. Hence, next-generation vaccines that effectively induce immunity against pulmonary anthrax are urgently needed. In the present study, we prepared an attenuated and low protease activity Bacillus anthracis strain A16R-5.1 by deleting five of its extracellular protease activity-associated genes and its lef gene through the CRISPR-Cas9 genome editing system. This mutant strain was then used to formulate a lethal toxin (LeTx)-free culture supernatant extract (CSE) anthrax vaccine, of which half was protective antigen (PA). We generated liquid, powder, and powder reconstituted formulations that could be delivered by aerosolized intratracheal inoculation. All of them induced strong humoral, cellular, and mucosal immune responses. The vaccines also produced LeTx neutralizing antibodies and conferred full protection against the lethal aerosol challenges of B. anthracis Pasteur II spores in mice. Compared to the recombinant PA vaccine, the CSE anthrax vaccine with equal PA content provided superior immunoprotection against pulmonary anthrax. The preceding results suggest that the CSE anthrax vaccine developed herein is suitable and scalable for use in inhalational immunization against pulmonary anthrax.
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Vacunas contra el Carbunco , Carbunco , Bacillus anthracis , Ratones , Animales , Carbunco/prevención & control , Vacunas contra el Carbunco/genética , Antígenos Bacterianos/genética , Polvos , Bacillus anthracis/genética , Vacunas Sintéticas , Péptido Hidrolasas , Anticuerpos AntibacterianosRESUMEN
The background to this research is stark and rather troubling: the ongoing accumulation of residual plastic film (RPF) in farmland ultimately threatens the sustainable development of agriculture and food security. In this study, we selected 15 counties in northern China to analyze the effect of RPF content on soil properties and crop yield and the driving factors through sampling and survey questionnaire. The linear mixed-effects model revealed the four main factors affecting RPF content, ranked as follows: plastic film mulching years > government recycling policy > spacing between rows > recycling methods (0.47493 > 0.25635 > 0.23380 > 0.17001). The contribution value of plastic film thickness was very low (R2(M) = 0.099). The plastic film width and spacing within rows did not significantly affect RPF content. The structural equation model showed that the RPF had both direct (-0.111) and indirect (-0.010) effects on maize yield. A 1 kg ha-1 increase in RPF content decreased maize yield by 27.67 kg ha-1. RPF did not directly affect soil organic carbon (SOC), pH, or ammonium nitrogen. RPF mainly aggravated soil salinization by increasing soil nitrate-nitrogen, available phosphorus, and available potassium, increasing SOC and decreasing pH, thus reducing crop yield. To the best of our knowledge, this is the first study to combine the driving factors of RPF accumulation and the effects of RPF on soil properties and crop yield in a large-scale sampling and survey questionnaire. RPF accumulation in the study area has aggravated soil salinization and reduced crop yields. Hence, measures are needed to alleviate the current situation. Local governments should formulate RPF recovery policies based on their actual situation. At the national level, more research is needed to develop RPF recovery machinery to improve efficiency.
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Plásticos , Suelo , Carbono , Agua/análisis , Agricultura/métodos , Zea mays , China , Nitrógeno/análisis , FertilizantesRESUMEN
Hypervirulent Klebsiella pneumoniae (hvKp) can cause life-threatening community-acquired infections among healthy young individuals and is thus of concern for global dissemination. In this study, a mouse model of acute primary hvKp pneumonia was established via aerosolized intratracheal (i.t.) inoculation, laying the foundation for conducting extensive studies related to hvKp. Subsequently, a time-course transcriptional profile was created of the lungs from the mouse model at 0, 12, 24, 48 and 60 hours post-infection (hpi) using RNA Sequencing (RNA-Seq). RNA-Seq data were analyzed with the use of Mfuzz time clustering, weighted gene co-expression network analysis (WGCNA) and Immune Cell Abundance Identifier for mouse (ImmuCellAI-mouse). A gradual change in the transcriptional profile of the lungs was observed that reflected expected disease progression. At 12 hpi, genes related to acute phase inflammatory response increased in expression and lipid metabolism appeared to have a pro-inflammatory effect. At 24 hpi, exacerbation of inflammation was observed and active IFN-γ suggested that signaling promoted activation and recruitment of macrophages occurred. Genes related to maintaining the structural integrity of lung tissues showed a sustained decrease in expression after infection and the decrease was especially marked at 48 hpi. TNF, IL-17, MAPK and NF-kB signaling pathways may play key roles in the immunopathogenesis mechanism at all stages of infection. Natural killer (NK) cells consistently decreased in abundance after infection, which has rarely been reported in hvKp infection and could provide a new target for treatment. Genes Saa1 and Slpi were significantly upregulated during infection. Both Saa1, which is associated with lipopolysaccharide (LPS) that elicits host inflammatory response, and Slpi, which encodes an antimicrobial protein, have not previously been reported in hvKp infections and could be important targets for subsequent studies. To t our knowledge, this paper represents the first study to investigate the pulmonary transcriptional response to hvKp infection. The results provide new insights into the molecular mechanisms underlying the pathogenesis of hvKp pulmonary infection that can contribute to the development of therapies to reduce hvKp pneumonia.
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Infecciones por Klebsiella , Neumonía , Animales , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Klebsiella pneumoniae/genética , Pulmón , RatonesRESUMEN
Controlling of radical reactivity by binding a radical to the metal center is an elegant strategy to overcome the challenge that radical intermediates are "too reactive to be selective". Yet, its application has seemingly been limited to a few strained-ring substrates, azide compounds, and diazo compounds. Meanwhile, first-row transition-metal-catalyzed (mainly, Fe, Ni, Cu) transformations of oxime esters have been reported recently in which the activation processes are assumed to follow free-radical mechanisms. In this work, we show by means of density functional theory calculations that the activation of oxime esters catalyzed by Fe(II) and Cu(I) catalysts more likely affords a metal-bound iminyl radical, rather than the presumed free iminyl radical, and the whole process follows a metal-bound radical mechanism. The as-formed metal-bound radical intermediates are an Fe(III)-iminyl radical (Stotal = 2, SFe = 5/2, and Siminyl = -1/2) and a Cu(II)-iminyl radical (Stotal = 0, SCu = 1/2, and Siminyl = -1/2). The discovery of such novel substrates affording metal-bound radical intermediates may facilitate the experimental design of metal-catalyzed asymmetric synthesis using oxime esters to achieve the desired enantioselectivity.
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Aerosol samplers are critical tools for studying indoor and outdoor aerosols. Development and evaluation of samplers is often labor-intensive and time-consuming due to the need to use monodisperse aerosols spanning a range of sizes. This study develops a rapid experimental methodology using polydisperse solid aerosols to evaluate size-resolved aerosol-to-aerosol (AtoA) and aerosol-to-hydrosol (AtoH) sampling efficiencies. Arizona Test Dust (diameter 0.5-20 µm) was generated and dispersed into an aerosol test chamber and two candidate samplers were tested. For the AtoA test, aerosols upstream and downstream of a sampler were measured using an online aerodynamic particle sizer. For the AtoH test, aerosols collected in sampling medium were mixed with a reference sample and then measured by the laser diffraction method. The experimental methodology were validated as an impressive time-saving procedure, with reasonable spatial uniformity and time stability of aerosols in the test chamber and an acceptable accuracy of absolute mass quantification of collected particles. Evaluation results showed that the AGI-30 and the BioSampler sampler had similar size-resolved sampling efficiencies and that efficiencies decreased with decreasing sampling flow rate. The combined evaluation of AtoA and AtoH efficiency provided more comprehensive performance indicators than either test alone. The experimental methodology presented here can facilitate the design and choice of aerosol sampler.
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Polvo , Monitoreo del Ambiente , Aerosoles/análisis , Polvo/análisis , Eficiencia , Monitoreo del Ambiente/métodos , Diseño de Equipo , Tamaño de la PartículaRESUMEN
Pneumonic plague, caused by Yersinia pestis, is an infectious disease with high mortality rates unless treated early with antibiotics. Currently, no FDA-approved vaccine against plague is available for human use. The capsular antigen F1, the low-calcium-response V antigen (LcrV), and the recombinant fusion protein (rF1-LcrV) of Y. pestis are leading subunit vaccine candidates under intense investigation; however, the inability of recombinant antigens to provide complete protection against pneumonic plague in animal models remains a significant concern. In this study, we compared immunoprotection against pneumonic plague provided by rF1, rV10 (a truncation of LcrV), and rF1-V10, and vaccinations delivered via aerosolized intratracheal (i.t.) inoculation or subcutaneous (s.c.) injection. We further considered three vaccine formulations: conventional liquid, dry powder produced by spray freeze drying, or dry powder reconstituted in PBS. The main findings are: (i) rF1-V10 immunization with any formulation via i.t. or s.c. routes conferred 100% protection against Y. pestis i.t. infection; (ii) rF1 or rV10 immunization using i.t. delivery provided significantly stronger protection than rF1 or rV10 immunization via s.c. delivery; and (iii) powder formulations of subunit vaccines induced immune responses and provided protection equivalent to those elicited by unprocessed liquid formulations of vaccines. Our data indicate that immunization with a powder formulation of rF1-V10 vaccines via an i.t. route may be a promising vaccination strategy for providing protective immunity against pneumonic plague.
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Vacuna contra la Peste/inmunología , Peste/prevención & control , Vacunas de Subunidad/inmunología , Yersinia pestis/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Modelos Animales de Enfermedad , Composición de Medicamentos , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunidad Mucosa , Inmunización/métodos , Ratones , Ratones Endogámicos BALB C , Especificidad de Órganos , Peste/inmunología , Peste/mortalidad , Vacuna contra la Peste/administración & dosificación , Vacuna contra la Peste/química , Proteínas Recombinantes/inmunología , Aerosoles y Gotitas Respiratorias , Mucosa Respiratoria/inmunología , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/químicaRESUMEN
Anthrax caused by Bacillus anthracis is a fatal zoonotic disease with a high lethality and poor prognosis. Inhalational anthrax is the most severe of the three forms of anthrax. The currently licensed commercial human anthrax vaccines require a complex immunization procedure for efficacy and have side effects that limit its use in emergent situations. Thus, development of a better anthrax vaccine is necessary. In this study, we evaluate the potency and efficacy of aerosolized intratracheal (i.t.) inoculation with recombinant protective antigen (rPA) subunit vaccines against aerosolized B. anthracis Pasteur II spores (an attenuated strain) challenge in a B10.D2-Hc0 mouse (deficient in complement component C5) model. Immunization of rPA in liquid, powder or powder reconstituted formulations via i.t. route conferred 100% protection against a 20× LD50 aerosolized Pasteur II spore challenge in mice, compared with only 50% of subcutaneous (s.c.) injection with liquid rPA. Consistently, i.t. inoculation of rPA vaccines induced a higher lethal toxin (LeTx) neutralizing antibody titer, a stronger lung mucosal immune response and a greater cellular immune response than s.c. injection. Our results demonstrate that immunization with rPA dry powder vaccine via i.t. route may provide a stable and effective strategy to improve currently available anthrax vaccines and B10.D2-Hc0 mice challenged with B. anthracis attenuated strains might be an alternative model for anthrax vaccine candidate screening.
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Vacunas contra el Carbunco/inmunología , Carbunco/prevención & control , Antígenos Bacterianos/inmunología , Toxinas Bacterianas/inmunología , Inmunidad Mucosa , Vacunación/métodos , Administración Intranasal , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Neutralizantes/sangre , Bacillus anthracis/inmunología , Femenino , Inmunoglobulina G/sangre , Ratones , Polvos , Análisis de Supervivencia , Vacunas de Subunidad/inmunología , Vacunas Sintéticas/inmunologíaRESUMEN
Objective: Pneumonia is a common pulmonary complication of flail chest, causing high morbidity and mortality rates in affected patients. The existing methods for identifying pneumonia have low accuracy, and their use may delay antimicrobial therapy. However, machine learning can be combined with electronic medical record systems to identify information and assist in quick clinical decision-making. Our study aimed to develop a novel machine-learning model to predict pneumonia risk in flail chest patients. Methods: From January 2011 to December 2021, the electronic medical records of 169 adult patients with flail chest at a tertiary teaching hospital in an urban level I Trauma Centre in Chongqing were retrospectively analysed. Then, the patients were randomly divided into training and test sets at a ratio of 7:3. Using the Fisher score, the best subset of variables was chosen. The performance of the seven models was evaluated by computing the area under the receiver operating characteristic curve (AUC). The output of the XGBoost model was shown using the Shapley Additive exPlanation (SHAP) method. Results: Of 802 multiple rib fracture patients, 169 flail chest patients were eventually included, and 86 (50.80%) were diagnosed with pneumonia. The XGBoost model performed the best among all seven machine-learning models. The AUC of the XGBoost model was 0.895 (sensitivity: 84.3%; specificity: 80.0%).Pneumonia in flail chest patients was associated with several features: systolic blood pressure, pH value, blood transfusion, and ISS. Conclusion: Our study demonstrated that the XGBoost model with 32 variables had high reliability in assessing risk indicators of pneumonia in flail chest patients. The SHAP method can identify vital pneumonia risk factors, making the XGBoost model's output clinically meaningful.
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With the development of sensor technology and learning algorithms, multimodal emotion recognition has attracted widespread attention. Many existing studies on emotion recognition mainly focused on normal people. Besides, due to hearing loss, deaf people cannot express emotions by words, which may have a greater need for emotion recognition. In this paper, the deep belief network (DBN) was utilized to classify three category emotions through the electroencephalograph (EEG) and facial expressions. Signals from 15 deaf subjects were recorded when they watched the emotional movie clips. Our system uses a 1-s window without overlap to segment the EEG signals in five frequency bands, then the differential entropy (DE) feature is extracted. The DE feature of EEG and facial expression images plays as multimodal input for subject-dependent emotion recognition. To avoid feature redundancy, the top 12 major EEG electrode channels (FP2, FP1, FT7, FPZ, F7, T8, F8, CB2, CB1, FT8, T7, TP8) in the gamma band and 30 facial expression features (the areas around the eyes and eyebrow) which are selected by the largest weight values. The results show that the classification accuracy is 99.92% by feature selection in deaf emotion reignition. Moreover, investigations on brain activities reveal deaf brain activity changes mainly in the beta and gamma bands, and the brain regions that are affected by emotions are mainly distributed in the prefrontal and outer temporal lobes.
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Electroencefalografía , Expresión Facial , Encéfalo , Cognición , Electroencefalografía/métodos , Emociones , HumanosRESUMEN
High-risk drivers are more likely to be involved in traffic accidents, and the driving risk level of drivers could be affected by many potential factors, such as demographics and personality traits. Based on the Structural Equation Model (SEM), this study involves a sample of 3150 drivers from the Strategic Highway Research Program 2 (SHRP 2), to explore the relationships among drivers' demographic characteristics (gender, age, and cumulative driving years), sensation seeking, risk perception, and risky driving behaviors. More specifically, the mediation model of driver characteristics on risky driving behaviors moderated by gender is constructed by the SEM. The results show that the effects of driving experience on risky driving behaviors are partially mediated by sensation seeking and risk perception for male drivers, while those are completely mediated by sensation seeking and risk perception for female drivers. Moreover, the development trend of risky driving behavior engagements declines greater with the growing of driving experience for female drivers than male drivers. Finally, a classification model of the driver's driving risk is proposed by the Random Forest classifier, in which the driving risk level of the driver evaluated by the crash and near-crash rate could be classified through the driver's self-reported demographics, sensation seeking, risk perception, and risky driving behaviors. The classification accuracy achieves up to 90 percent, which offers an alternative approach to identifying potential high-risk drivers to reduce property losses, injuries, and death caused by traffic accidents.
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Accidentes de Tránsito , Conducción de Automóvil , Femenino , Humanos , Masculino , Asunción de RiesgosRESUMEN
Graphene-based nanomaterials, including graphene oxide (GO) and reduced graphene oxide (rGO), play key roles in the nanozyme field. GO and rGO carrying various oxygen-containing functional groups, including epoxy, hydroxyl, ether, endoperoxide, carbonyl, carboxyl, and ester, have been reported to display peroxidase mimicking activities. However, the active center and the underlying mechanism responsible for its peroxidase mimicking activities still remain unclear. Herein, taking the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) by H2O2 as the model reaction, we investigate the possible catalytic mechanisms using DFT calculations. The results indicate that the carbonyl groups are the active centers. The activation of the C[double bond, length as m-dash]O bond is the key step in the catalytic cycle. The results will help realize the rational design of carbon-based nanozymes.
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The number of apple (Malus pumila Mill.) orchards has increased substantially in hilly regions of the Loess Plateau of China, as a significant element of the large-scale 'Grain for Green' ecological rehabilitation program that aims to conserve soil and water while improving the regions economic prospects. However, the long-term effects of the orchard expansion and the adaptive responses of apple trees to drought are not known. Thus, using a space-for-time substitution approach, we investigated plant-available water and fine-root distribution in the 0-8 m soil profile in apple orchards of various ages in a dry year (2015, 392 mm rainfall) and the following year with normal precipitation (2016, 500 mm rainfall). We found that plant-available water gradually decreased with stand age in the dry year, but increased in the normal year, especially in the 0-2 m soil layer. Fine root (<2 mm diameter) distribution and biomass increased with stand age and decreased with increasing soil depth in all treatment plots, predominantly in the 0-2 m layer. In all treatment plots, most of the soil layers in the deep soil (>2 m) had soil moisture storage deficit. In the dry year (2015), the apple trees increased both the average depth (D50 and D95 values) and biomass of their fine-root systems in response to water stress, relative to the normal year (2016). Thus, the apple trees extracted water primarily from the shallow (<2 m) layers in the normal year, but from deeper soil layers in the dry year, to sustain growth. The results of this study will help to guide land and agricultural water management in rainfed apple orchards in hilly regions of the Loess Plateau and similar dryland regions.
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Malus , China , Sequías , Suelo , AguaRESUMEN
Accumulating articles reported that berberine (Ber) played a neuroprotective role in Alzheimer's disease (AD). Long noncoding RNAs (lncRNAs) have been identified as biomarkers and therapeutic targets of AD. However, the precise mechanism by which lncRNA ß-amyloid cleaving enzyme 1 antisense RNA (BACE1-AS)regulates the progression of AD remains largely unknown. HPN and SK-N-SH cells treated with amyloid ß 25-35 (Aß25-35) were regarded as AD model in vitro. Cell survival rate was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Lactate dehydrogenase (LDH) cytotoxicity assay was conducted to detect the cytotoxicity of neuronal cells. Flow cytometry was performed to determine the intracellular concentration of Ca2+, reactive oxygen species (ROS) and apoptosis of neuronal cells. Western blot assay was carried out to detect the apoptosis-related proteins of neuronal cells. The abundance of lncRNA BACE1-AS and miR-132-3p was measured by quantitative real time polymerase chain reaction (qRT-PCR). The binding sites between miR-132-3p and BACE1-AS were predicted by Starbase, and the combination was confirmed by dual-luciferase reporter assay. We found that Ber alleviated Aß25-35 induced neuronal injury in AD model, especially in high concentration Ber group. The enrichment of BACE1-AS was positively regulated by Aß25-35 and was inversely modulated by Ber in neuronal cells. The interference of BACE1-AS alleviated the neuronal damage of AD model. miR-132-3p was a direct target of lncRNA BACE1-AS in HEK293T cells, and it was negatively regulated by BACE1-AS in neuronal cells. BACE1-AS accumulation reversed the protective effect of miR-132-3p overexpression on AD model. Ber treatment and BACE1-AS intervention recovered the viability of AD model. Ber up-regulated the level of miR-132-3p via BACE1-AS in SK-N-SH and HPN neuronal cells. in conclucsion, Ber protected neuronal cells against Aß25-35 at least partly through BACE1-AS/miR-132-3p axis. The combined therapy of Ber treatment with BACE1-AS depletion might provide new insight into AD treatment.