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2'-Deoxynucleosides and analogues play a vital role in drug development, but their preparation remains a significant challenge. Previous studies have focused on ß-2'-deoxynucleosides with the natural ß-configuration. In fact, their isomeric α-2'-deoxynucleosides also exhibit diverse bioactivities and even better metabolic stability. Herein, we report that both α- and ß-2'-deoxynucleosides can be prepared with high yields and stereoselectivity using a remote directing diphenylphosphinoyl (DPP) group. It is particularly efficient to prepare α-2'-deoxynucleosides with an easily accessible 3,5-di-ODPP donor. Instead of acting as a H-bond acceptor on a 2-(diphenylphosphinoyl)acetyl (DPPA) group in our previous studies for syn-facial O-glycosylation, the phosphine oxide moiety here acts as a remote participating group to enable highly antifacial N-glycosylation. This proposed remote participation mechanism is supported by our first characterization of an important 1,5-briged P-heterobicyclic intermediate via variable-temperature NMR spectroscopy. Interestingly, antiproliferative assays led to a α-2'-deoxynucleoside with IC50 values in the low micromole range against central nervous system tumor cell lines SH-SY5Y and LN229, whereas its ß-anomer exhibited no inhibition at 100 µM. Furthermore, the DPP group significantly enhanced the antitumor activities by 10 times.
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Neuroblastoma , Fosfinas , Humanos , GlicosilaciónRESUMEN
BACKGROUND: The latitudinal diversity gradient (LDG), characterized by an increase in species richness from the poles to the equator, is one of the most pervasive biological patterns. However, inverse LDGs, in which species richness peaks in extratropical regions, are also found in some lineages and their causes remain unclear. Here, we test the roles of evolutionary time, diversification rates, and niche conservatism in explaining the inverse LDG of Potentilla (ca. 500 species). We compiled the global distributions of ~ 90% of Potentilla species, and reconstructed a robust phylogenetic framework based on whole-plastome sequences. Next, we analyzed the divergence time, ancestral area, diversification rate, and ancestral niche to investigate the macroevolutionary history of Potentilla. RESULTS: The genus originated in the Qinghai-Tibet Plateau during the late Eocene and gradually spread to other regions of the Northern Hemisphere posterior to the late Miocene. Rapid cooling after the late Pliocene promoted the radiating diversification of Potentilla. The polyploidization, as well as some cold-adaptive morphological innovations, enhanced the adaptation of Potentilla species to the cold environment. Ancestral niche reconstruction suggests that Potentilla likely originated in a relatively cool environment. The species richness peaks at approximately 45 °N, a region characterized by high diversification rates, and the environmental conditions are similar to the ancestral climate niche. Evolutionary time was not significantly correlated with species richness in the latitudinal gradient. CONCLUSIONS: Our results suggest that the elevated diversification rates in middle latitude regions and the conservatism in thermal niches jointly determined the inverse LDG in Potentilla. This study highlights the importance of integrating evolutionary and ecological approaches to explain the diversity pattern of biological groups on a global scale.
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Biodiversidad , Filogenia , Potentilla , Potentilla/genética , Potentilla/fisiología , Ecosistema , Evolución BiológicaRESUMEN
Starfish provide important saponins with diverse bioactivities as the secondary metabolites, among which 2-O-glycosylated glycosides are commonly found. Preparation of those 1,2-trans 2-O-glycosylated glycosides usually relies on 2-O-acyl participation requiring the selective installation and cleavage of 2-O-acyl groups. A convergent synthesis using 2-O-glycosylated oligosaccharide donors would be more straightforward but also pose greater challenges. Herein, we report a convergent synthesis of a distinctive tetrasaccharide isolated from starfish Asterias rollestoni Bell. Dual 2-(diphenylphosphinoyl)acetyl (DPPA) groups at O3 and O4 on galactose moiety led to high ß-selectivities (ß/α=12/1 or ß only) in the challenging [2+2] glycosylation, giving the desired tetrasaccharides in >90 % yields from the 2-O-glycosylated disaccharide donors. These synthetic studies have also unambiguously revised the structure of these natural tetrasaccharides. This work would facilitate further studies on new inhibitors of α-glucosidase as hypoglycemic drugs.
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Oligosacáridos , Animales , Glicosilación , Oligosacáridos/química , Oligosacáridos/síntesis química , Asterias/química , Glicósidos/química , Saponinas/química , Saponinas/síntesis química , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/químicaRESUMEN
BACKGROUND: Chitinase-3 like-protein-1 (CHI3L1) is a member of the mammalian chitinase-like proteins and elevated serum CHI3L1 level has been proved to be associated with poor prognosis in hepatocellular carcinoma (HCC). This study aimed to investigate the relationship between serum CHI3L1 levels and body composition parameters in patients with HCC after liver transplantation (LT). METHODS: This retrospective study enrolled 200 patients after LT for HCC. Blood samples were collected and serum concentrations of CHI3L1 were measured by enzyme-linked immunosorbent assay. Computer tomography (CT) were used to estimate skeletal muscle and adipose tissue mass. Spearman's rank correlation test was performed to assess associations between serum CHI3L1 levels and these body composition parameters. A Cox proportional-hazards regression model was performed to identify independent prognostic factors. Overall survival (OS) and recurrence-free survival (RFS) curves were constructed using the Kaplan-Meier method and compared by the log-rank test. RESULTS: Total 71 patients (35.5%) were diagnosed with myosteatosis according to skeletal muscle radiation attenuation (SMRA). The 5-year OS rates were 66.9% in non-myosteatosis group, significantly higher than 49.5% in myosteatosis group (p = 0.025), while the RFS of myosteatosis group (5-year RFS: 52.6%) or non-myosteatosis group (5-year RFS: 42.0%) shown no significant difference (p = 0.068). The serum CHI3L1 level were significantly negative correlated with SMRA (r = -0.3, p < 0.001). Interestingly, in patients with myosteatosis, Kaplan-Meier analysis revealed that elevated serum CHI3L1 levels were associated with worse OS (p < 0.001) and RFS (p = 0.047). However, in patients without myosteatosis, Kaplan-Meier analysis found elevated serum CHI3L1 levels were not associated with OS (p = 0.070) or RFS (p = 0.104). CONCLUSIONS: Elevated CHI3L1 was negatively correlated with SMRA, and predicted poorer prognosis in Chinese population after LT for HCC, especially in those patients with concomitant myosteatosis. Monitoring serum CHI3L1 can predict prognosis and effectively guide individual nutrition intervention.
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Biomarcadores de Tumor , Carcinoma Hepatocelular , Proteína 1 Similar a Quitinasa-3 , Neoplasias Hepáticas , Humanos , Proteína 1 Similar a Quitinasa-3/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Femenino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Biomarcadores de Tumor/sangre , Composición Corporal , Músculo Esquelético/patología , Músculo Esquelético/metabolismo , Músculo Esquelético/diagnóstico por imagen , Trasplante de Hígado , Adulto , Anciano , Tejido Adiposo/patología , Tejido Adiposo/metabolismo , Estimación de Kaplan-Meier , Tomografía Computarizada por Rayos XRESUMEN
Volatile organic compounds (VOCs) significantly affect the air quality in aircraft cabins, consequently affecting passenger health and comfort. Although VOC emission sources and their contributions have been studied extensively, the distribution characteristics of VOCs originating from diverse sources within cabins have received limited attention, and the correlation between VOC sources and concentrations in passenger breathing zones remains largely unexplored. To fill this knowledge gap, the concentration field of VOCs was investigated using a computational fluid dynamics model, and the results were experimentally validated in a typical single-aisle aircraft cabin with seven seat rows. The diffusion characteristics of different VOCs emitted by four typical sources in aircraft cabins (floors, human surfaces, seats, and respiratory sources) were analyzed and compared. The distribution of VOCs emitted by different sources was nonuniform and could be classified into two distinct categories. When the emission intensities of all sources were equal, the average concentration of VOCs emitted from the floor source were considerably lower in the passenger breathing zone (4.01 µg/m³) than those emitted from the human surface, seat, and respiratory sources, which exhibited approximately equal concentrations (6.82, 6.90, and 7.29 µg/m³, respectively). The analysis highlighted that the simplified lumped-parameter method could not accurately estimate the exposure concentrations within an aircraft cabin. To address this issue, we propose a correction method based on the emission intensity of each VOC source. This study provides critical insights into the diffusion characteristics of VOCs within aircraft cabins and VOC emissions from various sources.
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Contaminantes Atmosféricos , Contaminación del Aire , Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Contaminación del Aire/análisis , Aeronaves , Pisos y Cubiertas de Piso , Hidrodinámica , Contaminantes Atmosféricos/análisis , Monitoreo del AmbienteRESUMEN
BACKGROUND: Older migrant workers (OMWs) in China face unique challenges rooted in their early life experiences, which increase their vulnerability to psychological and behavioral problems in adulthood. By utilizing the cumulative disadvantage model and the social-ecological systems theory, this study explored the effect of childhood family adversity on adulthood depression in the mediating roles of OMWs' social-ecological microsystem and mesosystem and further examined gender differences in these associations. METHODS: Data were collected from the China Health and Retirement Longitudinal Study (CHARLS), involving a sample of 4,309 OMWs aged 50 and above. The measures included the Center for Epidemiological Research Depression Scale, childhood family adversity, socioeconomic status, marital quality, and physical and cognitive health. RESULTS: Childhood family adversity was positively associated with adulthood depression among OMWs. Social microsystem (physical and cognitive health) and mesosystem (marital quality and socioeconomic status) factors significantly mediated this relationship. Multi-group analysis revealed that the mediating effects of marital quality and socioeconomic status were stronger for female OMWs, while the mediating effects of physical and cognitive health were stronger for male OMWs. CONCLUSIONS: The findings suggest that childhood family adversity has a lasting impact on the mental health of OMWs, and that social-ecological systems factors play an important role in this relationship. The study also highlights the need for gender-specific interventions to address the mental health needs of OMWs.
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Depresión , Migrantes , Humanos , Masculino , Femenino , China/epidemiología , Migrantes/psicología , Migrantes/estadística & datos numéricos , Persona de Mediana Edad , Depresión/epidemiología , Depresión/psicología , Estudios Longitudinales , Factores Sexuales , Anciano , Experiencias Adversas de la Infancia/estadística & datos numéricos , Experiencias Adversas de la Infancia/psicología , Medio Social , Pueblos del Este de AsiaRESUMEN
BACKGROUND: There is a great challenge to sedation for infants with cleft lip and palate undergoing CT scan, because there is the younger age and no consensus on the type, dosage, and route of drug administration. OBJECTIVE: This study aimed to evaluate the efficacy of intranasal administration of dexmedetomidine combined with midazolam as a sedative option for infants with cleft lip and palate under imaging procedures. METHODS: Infants scheduled for cleft lip and palate repair surgery were randomly assigned to the IND group (intranasal dexmedetomidine 2 µg/kg alone) and the INDM group (intranasal dexmedetomidine 2 µg/kg combined with midazolam 0.05 mg/kg). The primary outcome was the proportion of infants underwent successful computed tomography (CT) scans under intranasal sedation. The secondary outcomes included onset time and duration of sedation, recovery time, Ramsay sedation scale, hemodynamic parameters during sedation, and adverse events. Data analyses involved the unpaired t-test, the repeated-measures analysis of variance test, and the continuity correction χ2 test. RESULTS: One hundred five infants were included in the analysis. The proportion of infants underwent successful CT scans under sedation was significantly greater in the INDM group than in the IND group (47 [95.9%] vs. 45 [80.4%], p = 0.016). Additionally, the INDM group had a shorter onset time and a longer duration of sedation statistically (12 [8.5, 17] min vs. 16 [12, 20] min, p = 0.001; 80 [63.6, 92.5] min vs. 68.5 [38, 89] min, p = 0.014, respectively), and their recovery time was significantly longer (43 [30, 59.5] min vs. 31.5 [20.5, 53.5] min, p = 0.006). The difference in Ramsay sedation scale values 20 min after administration was statistically significant between the groups. No statistically significant difference was found between the groups in changes in heart rate and respiratory rate. CONCLUSION: Intranasal administration of dexmedetomidine in combination with midazolam resulted in higher sedation success in comparison with sole dexmedetomidine. However, it has a relatively prolonged duration of sedation and recovery time. TRIAL REGISTRATION: ChiCTR2100049122, Clinical trial first registration date: 21/07/2021.
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Labio Leporino , Fisura del Paladar , Dexmedetomidina , Lactante , Humanos , Midazolam , Labio Leporino/cirugía , Administración Intranasal , Fisura del Paladar/cirugía , Hipnóticos y Sedantes , Tomografía Computarizada por Rayos XRESUMEN
PURPOSE: Awake extubation and deep extubation are commonly used anesthesia techniques. In this study, the safety of propofol-assisted deep extubation in the dental treatment of children was assessed. MATERIALS AND METHODS: Children with severe caries who received dental treatment under general anesthesia and deep extubation between January 2017 and June 2023 were included in this study. Data were collected on the following variables: details and time of anesthesia, perioperative vital signs, and incidence of postoperative complications. The incidence of laryngeal spasm (LS) was considered to be the primary observation indicator. RESULTS: The perioperative data obtained from 195 children undergoing dental treatment was reviewed. The median age was 4.2 years (range: 2.3 to 9.6 years), and the average duration of anesthesia was 2.56 h (range 1 to 4.5 h). During intubation with a videoscope, purulent mucus was found in the pharyngeal cavity of seven children (3.6%); LS occurred in five of them (2.6%), and one child developed a fever (T = 37.8 °C) after discharge. Five children (2.6%) experienced emergence agitation (EA) in the recovery room. Also, 13 children (6.7%) experienced epistaxis; 10 had a mild experience and three had a moderate experience. No cases of airway obstruction (AO) and hypoxemia were recorded. The time to open eyes (TOE) was 16.3 ± 7.2 min. The incidence rate of complications was 23/195 (11.8%). Emergency tracheal reintubation was not required. Patients with mild upper respiratory tract infections showed a significantly higher incidence of complications (P < 0.001). CONCLUSIONS: Propofol-assisted deep extubation is a suitable technique that can be used for pediatric patients who exhibited non-cooperation in the outpatient setting. Epistaxis represents the most frequently encountered complication. Preoperative upper respiratory tract infection significantly increases the risk of complications. The occurrence of EA was notably lower than reported in other studies.
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Extubación Traqueal , Propofol , Humanos , Extubación Traqueal/métodos , Preescolar , Estudios Retrospectivos , Propofol/administración & dosificación , Propofol/efectos adversos , Niño , Masculino , Femenino , Anestésicos Intravenosos , Anestesia General/métodos , Complicaciones Posoperatorias/epidemiología , Laringismo/epidemiología , Intubación Intratraqueal/métodos , Anestesia Dental/métodosRESUMEN
Food contaminated by mycotoxins has become a worldwide public problem with political and economic implications. Although a variety of traditional methods have been used to eliminate mycotoxins from agri-foods, the results have been somewhat less than satisfactory. As an emerging non-thermal processing technology, atmospheric cold plasma (ACP) has great potential for food decontamination. Herein, this review mainly presents the degradation efficiency of ACP on mycotoxins in vitro and agri-foods as well as its possible degradation mechanisms. Meanwhile, ACP effects on food quality, factors affecting the degradation efficiency and the toxicity of degradation products are also discussed. According to the literatures, ACP could efficiently degrade many mycotoxins (e.g., aflatoxin, deoxynivalenol, zearalenone, ochratoxin A, fumonisin, and T-2 toxin) both in vitro and various foods (e.g., hazelnut, peanut, maize, rice, wheat, barley, oat flour, and date palm fruit) with little effects on the nutritional and sensory properties of food. The degradation efficacy was dependent on many factors including ACP treatment parameter, working gas, mycotoxin property, and food substrate. The mycotoxin degradation by ACP was mainly attributed to the reactive oxygen and nitrogen species in ACP, which can damage the chemical bonds of mycotoxins, consequently reducing the toxicity of mycotoxins.
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Fumonisinas , Micotoxinas , Gases em Plasma , Zearalenona , Micotoxinas/toxicidad , Gases em Plasma/química , Contaminación de Alimentos/análisis , Fumonisinas/análisisRESUMEN
Deoxynivalenol (DON) is one of the most common mycotoxins distributed in food and feed, which causes severe liver injury in humans and animals. Cold atmospheric plasma (CAP) has received much attention in mycotoxin degradation due to the advantages of easy operation, high efficiency, and low temperature. So far, the majority of studies have focused on the degradation efficiency and mechanism of CAP on DON, while there is still little information available on the hepatotoxicity of DON after CAP treatment. Herein, this study aimed to investigate the effect of CAP on DON-induced hepatotoxicity both in vitro and in vivo and its underlying mechanisms. The results showed that 120-s CAP treatment achieved 97â¯% degradation of DON. The vitro hepatotoxicity of DON in L02 cells was significantly reduced with CAP treatment time. Meanwhile, CAP markedly alleviated DON-induced liver injury in mice including the balloon-like degeneration of liver tissues and elevation of AST and ALP level. The underlying mechanism for CAP detoxification of DON-induced hepatotoxicity was further elucidated. The results showed that DON caused severe oxidative stress in cells by suppressing the antioxidant signaling pathway of Nrf2/HO-1/NQO-1, consequently leading to mitochondrial dysfunction and cell apoptosis, accompanied by cellular senescence and inflammation. CAP blocked DON inhibition on the Nrf2/HO-1/NQO-1 signaling pathway through the efficient degradation of DON, accordingly alleviating the oxidative stress and liver injury induced by DON. Therefore, CAP is an effective method to eliminate DON hepatotoxicity, which can be applied in the detoxification of mycotoxin-contaminated food and feed to ensure human and animal health.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Gases em Plasma , Tricotecenos , Animales , Ratones , Tricotecenos/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Estrés Oxidativo/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Apoptosis/efectos de los fármacos , Masculino , Humanos , Inactivación Metabólica , Línea CelularRESUMEN
Defect detection is an indispensable part of the industrial intelligence process. The introduction of the DETR model marked the successful application of a transformer for defect detection, achieving true end-to-end detection. However, due to the complexity of defective backgrounds, low resolutions can lead to a lack of image detail control and slow convergence of the DETR model. To address these issues, we proposed a defect detection method based on an improved DETR model, called the GM-DETR. We optimized the DETR model by integrating GAM global attention with CNN feature extraction and matching features. This optimization process reduces the defect information diffusion and enhances the global feature interaction, improving the neural network's performance and ability to recognize target defects in complex backgrounds. Next, to filter out unnecessary model parameters, we proposed a layer pruning strategy to optimize the decoding layer, thereby reducing the model's parameter count. In addition, to address the issue of poor sensitivity of the original loss function to small differences in defect targets, we replaced the L1 loss in the original loss function with MSE loss to accelerate the network's convergence speed and improve the model's recognition accuracy. We conducted experiments on a dataset of road pothole defects to further validate the effectiveness of the GM-DETR model. The results demonstrate that the improved model exhibits better performance, with an increase in average precision of 4.9% (mAP@0.5), while reducing the parameter count by 12.9%.
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A novel sandwich-type biosensor denoted as "MIP-analyte-Ab" was constructed on a glassy carbon electrode modified with gold nanoparticles (AuNPs@GCE), which is dedicated to explore a general solution for electrochemical tests in a relatively high potential range on Au electrodes. In particular, parasitic reactions of Au oxidation severely hindered the electrochemiluminescence (ECL) reactions of the Ru(bpy)32+/tripropylamine (TPrA) system. In this work, we designed an ultra-fast redox pulse to alleviate reversible oxidation of Au with a potential range of -0.5 to 0.9 V. Stable ECL signals were generated in the last 3 ms of each run (RSD = 5.86%), and interesting mechanisms were revealed. The ultra-high-frequency sampler indicated that free diffusion of TPrAâ¢+ was the rate-determining step at 0.9 V, and it followed a totally different route with ECL at 1.3 V. Furthermore, we proposed a particular ECL reaction route at 0.9 V with C5 desosamine of the analyte, azithromycin, involved for the first time, based on results of radical identification. We believe that our work paved the way for the application of Au-based sandwich-type biosensors in environmental monitoring.
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Técnicas Biosensibles , Nanopartículas del Metal , Oro , Mediciones Luminiscentes/métodos , Oxidación-Reducción , Técnicas Biosensibles/métodos , Electrodos , Técnicas Electroquímicas/métodosRESUMEN
BACKGROUND: Impatiens sect. Impatiens is distributed across the Northern Hemisphere and has diversified considerably, particularly within the Hengduan Mountains (HDM) in southwest China. Yet, the infra-sectional phylogenetic relationships are not well resolved, largely due to limited taxon sampling and an insufficient number of molecular markers. The evolutionary history of its diversification is also poorly understood. In this study, plastome data and the most complete sampling to date were used to reconstruct a robust phylogenetic framework for this section. The phylogeny was then used to investigate its biogeographical history and diversification patterns, specifically with the aim of understanding the role played by the HDM and past climatic changes in its diversification. RESULTS: A stable phylogeny was reconstructed that strongly supported both the monophyly of the section and its division into seven major clades (Clades I-VII). Molecular dating and ancestral area reconstruction suggest that sect. Impatiens originated in the HDM and Southeast China around 11.76 Ma, after which different lineages dispersed to Northwest China, temperate Eurasia, and North America, mainly during the Pliocene and Pleistocene. An intercontinental dispersal event from East Asia to western North America may have occurred via the Bering Land Bridge or Aleutian Islands. The diversification rate was high during its early history, especially with the HDM, but gradually decreased over time both within and outside the HDM. Multiple linear regression analysis showed that the distribution pattern of species richness was strongly associated with elevation range, elevation, and mean annual temperature. Finally, ancestral niche analysis indicated that sect. Impatiens originated in a relatively cool, middle-elevation area. CONCLUSIONS: We inferred the evolutionary history of sect. Impatiens based on a solid phylogenetic framework. The HDM was the primary source or pump of its diversity in the Northern Hemisphere. Orogeny and climate change may have also shaped its diversification rates, as a steady decrease in the diversification rate coincided with the uplift of the HDM and climate cooling. These findings provide insights into the distribution pattern of sect. Impatiens and other plants in the Northern Hemisphere.
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Balsaminaceae , Impatiens , Filogenia , Evolución Biológica , China , FilogeografíaRESUMEN
The progress from intelligent interactions and supplemented/augmented reality requires artificial skins to shift from the single-functional tactile paradigm. Dual-responsive sensors that can both detect pre-contact proximal events and tactile pressure levels enrich the perception dimensions and deliver additional cognitive information. Previous dual-responsive sensors show very limited utilizations only in proximity perception or approaching switches. Whereas, the approaching inputs from the environment should be able to convey more valuable messages. Herein, a flexible iontronic dual-responsive artificial skin is present. The artificial skin is sensitive to external object's applied pressure as well as its approaching, and can elicit information of target material categories encoded in the proximal inputs. Versatile applications are then demonstrated. Dual-mode human-machine interfaces are developed based on the devices, including a manipulation of virtual game characters, navigation and zooming in of electronic maps, and scrolling through electronic documents. More importantly, the proof-of-concept application of an entirely touchless material classification system is demonstrated. Three types of materials (metals, polymers, and human skins) are classified and predicted accurately. These features of the artificial skin make it highly promising for next-generation smart engineered electronics.
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Piel Artificial , Dispositivos Electrónicos Vestibles , Humanos , Tacto , Piel , ElectrónicaRESUMEN
Demonstrating the process of transregional biogeography and mechanisms underlying evolutionary radiations is crucial to understanding biological evolution. Here, we use Hydrangeeae (Hydrangeaceae), a tribe with a unique disjunct distribution and complex trait variations, using a solid phylogenetic framework, to investigate how geographical and climatic factors interact with functional traits to trigger plant evolutionary radiations. We constructed the first highly supported and dated phylogenetic framework using 79 protein-coding genes obtained from 81 plastomes, representing 63 species and all major clades, and found that most extant species originated from asynchronous diversification of two lineages undergoing repeated expansion and retraction, at middle and high latitudes of the Northern Hemisphere between East Asia and North America, during the Eocene to Pleistocene (driven by geologic and climatic dynamics). In accordance with these drivers, interactions of flora between central-eastern China and Japan occurred frequently after the Late Tertiary. We found that resource limitation and range fragmentation probably accelerated the diversification of Hydrangeeae, which supports the resource-use hypothesis. Our study sheds light on the evolutionary radiation and assembly of flora within East Asia, and the East Asian-North American disjunction, through integration of phylogenomic and biogeographic data with functional trait and ecological data.
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Hydrangeaceae , Filogenia , Evolución Biológica , Asia Oriental , América del Norte , FilogeografíaRESUMEN
The catalytic function of lysyl hydroxylase-2 (LH2), a member of the Fe(II)/αKG-dependent oxygenase superfamily, is to catalyze the hydroxylation of lysine to hydroxylysine in collagen, resulting in stable hydroxylysine aldehyde-derived collagen cross-links (HLCCs). Reports show that high amounts of LH2 lead to the accumulation of HLCCs, causing fibrosis and specific types of cancer metastasis. Some members of the Fe(II)/αKG-dependent family have also been reported to have intramolecular O2 tunnels, which aid in transporting one of the required cosubstrates into the active site. While LH2 can be a promising target to combat these diseases, efficacious inhibitors are still lacking. We have used computational simulations to investigate a series of 44 small molecules as lead compounds for LH2 inhibition. Tunneling analyses indicate the existence of several intramolecular tunnels. The lengths of the calculated O2-transporting tunnels in holoenzymes are relatively longer than those in the apoenzyme, suggesting that the ligands may affect the enzyme's structure and possibly block (at least partially) the tunnels. The sequence alignment analysis between LH enzymes from different organisms shows that all of the amino acid residues with the highest occurrence rate in the oxygen tunnels are conserved. Our results suggest that the enolate form of diketone compounds establishes stronger interactions with the Fe(II) in the active site. Branching the enolate compounds with functional groups such as phenyl and pyridinyl enhances the interaction with various residues around the active site. Our results provide information about possible leads for further LH2 inhibition design and development.
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Hidroxilisina , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa , Colágeno/química , Colágeno/metabolismo , Compuestos Ferrosos , Lisina/metabolismo , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/antagonistas & inhibidores , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/químicaRESUMEN
Ozone reactions on human body surfaces produce volatile organic compounds (VOCs) that influence indoor air quality. However, the dependence of VOC emissions on the ozone concentration has received limited attention. In this study, we conducted 36 sets of single-person chamber experiments with three volunteers exposed to ozone concentrations ranging from 0 to 32 ppb. Emission fluxes from human body surfaces were measured for 11 targeted skin-oil oxidation products. For the majority of these products, the emission fluxes linearly correlated with ozone concentration, indicating a constant surface yield (moles of VOC emitted per mole of ozone deposited). However, for the second-generation oxidation product 4-oxopentanal, a higher surface yield was observed at higher ozone concentrations. Furthermore, many VOCs have substantial emissions in the absence of ozone. Overall, these results suggest that the complex surface reactions and mass transfer processes involved in ozone-dependent VOC emissions from the human body can be represented using a simplified parametrization based on surface yield and baseline emission flux. Values of these two parameters were quantified for targeted products and estimated for other semiquantified VOC signals, facilitating the inclusion of ozone/skin oil chemistry in indoor air quality models and providing new insights on skin oil chemistry.
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Ozono , Compuestos Orgánicos Volátiles , Humanos , Cuerpo HumanoRESUMEN
Recent advances in the use of organic-inorganic hybrid perovskites for optoelectronics have been rapid, with reported power conversion efficiencies of up to 22 per cent for perovskite solar cells. Improvements in stability have also enabled testing over a timescale of thousands of hours. However, large-scale deployment of such cells will also require the ability to produce large-area, uniformly high-quality perovskite films. A key challenge is to overcome the substantial reduction in power conversion efficiency when a small device is scaled up: a reduction from over 20 per cent to about 10 per cent is found when a common aperture area of about 0.1 square centimetres is increased to more than 25 square centimetres. Here we report a new deposition route for methyl ammonium lead halide perovskite films that does not rely on use of a common solvent or vacuum: rather, it relies on the rapid conversion of amine complex precursors to perovskite films, followed by a pressure application step. The deposited perovskite films were free of pin-holes and highly uniform. Importantly, the new deposition approach can be performed in air at low temperatures, facilitating fabrication of large-area perovskite devices. We reached a certified power conversion efficiency of 12.1 per cent with an aperture area of 36.1 square centimetres for a mesoporous TiO2-based perovskite solar module architecture.
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BACKGROUND: Emerging evidence links outdoor air pollution and declined renal function but the relationship between household air pollution and renal function is not well understood. METHODS: Using cross-sectional data from the multi-provincial INTERMAP-China Prospective Study, we collected blood samples and questionnaire information on stove use and socio-demographic factors. We calculated estimated glomerular filtration rate (eGFR) from serum creatinine to assess renal function. Participants with eGFR <60 mL/min per 1.73 m2 were defined as having chronic kidney disease (CKD) in this analysis. Generalized estimating equations were used to estimate the association of household fuel with renal function and prevalent CKD in models adjusting for confounders. RESULTS: Among the 646 enrolled adults (40-79y; 56% female), one-third exclusively used clean fuel (gas and electric) cookstoves and 11% of northern China participants (n = 49 of 434) used only clean fuel heaters, whereas the rest used solid fuel. In multivariable models, use of solid fuel cookstoves was associated with 0.17 ml/min/1.73 m2 (95% CI: -0.30, 0.64) higher eGFR and 19% (0.86, 1.64) higher prevalence of CKD than exclusive clean fuel use. Greater intensity of solid fuel use was associated with 0.25 ml/min/1.73 m2 (-0.71, 0.21) lower eGFR per 5 stove-use years, though the confidence intervals included the null, while greater current intensity of indoor solid fuel use was associated with 1.02 (1.00, 1.04) higher prevalent CKD per 100 stove-use days per year. Larger associations between current solid fuel use and intensity of use with lower eGFR and prevalent CKD were observed among participants in southern China, those with hypertension or diabetes (eGFR only), and females (CKD only), through these groups had small sample sizes and some confidence intervals included the null. CONCLUSION: We found inconsistent evidence associating household solid fuel use and renal function in this cross-sectional study of peri-urban Chinese adults.
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Contaminación del Aire Interior , Contaminación del Aire , Combustibles Fósiles , Insuficiencia Renal Crónica , Anciano , Femenino , Humanos , Masculino , China/epidemiología , Estudios Transversales , Tasa de Filtración Glomerular , Riñón/fisiología , Estudios Prospectivos , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/epidemiología , Combustibles Fósiles/efectos adversosRESUMEN
BACKGROUND: Emergence agitation (EA) is an adverse complication during early recovery from sevoflurane anesthesia. Continuous intravenous infusion of dexmedetomidine (DEX) is commonly used for EA prevention. However, a wide dose range is used for preventing EA, and the optimal dose remains unknown. This study was aimed at determining the optimal dose (the 90% effective dose [ED90]) of DEX for continuous intraoperative infusion for EA prevention in children. METHODS: We enrolled children aged 3 to 7 years who underwent dental treatment under sevoflurane anesthesia. DEX was continuously infused from the time of the establishment of the intravenous access until 5 minutes before the end of surgery. The initial DEX dose was 0.5 µg/kg/h, and subsequent dose adjustments were determined based on the response of the previous patient by using an up-down sequential allocation with a biased-coin design. The primary outcome was the ED90 for continuous DEX infusion based on the success or failure of the EA-preventing dose. RESULTS: Forty-five patients were enrolled in the study. The DEX dose ranged from 0.50 to 0.90 µg/kg/h. The estimated ED90 (95% confidence interval [CI]) for preventing EA was 0.74 µg/kg/h (0.67-1.05 µg/kg/h). The duration of surgery (mean ± standard deviation [SD]) was 113 ± 30 minutes. The times (mean ± SD) for extubation, time to emergence, and recovery time were 5 ± 2 minutes, 27 ± 9 minutes, and 39 ± 7 minutes, respectively. CONCLUSIONS: The ED90 for continuous intraoperative DEX infusion for EA prevention in pediatric patients receiving dental treatment under sevoflurane anesthesia was 0.74 µg/kg/h (95% CI, 0.67-1.05 µg/kg/h).