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Organophosphorus pesticides (OPPs) constitute the most widely employed class of pesticides. However, the prevalent use of OPPs, while advantageous, raises concerns due to their toxicity, posing serious threats to food safety. Chemical sensors utilizing quantum dots (QDs) demonstrate promising applications in rapidly detecting OPPs residues, thereby facilitating efficient inspection of agricultural products. In this study, we employ an aqueous synthesis approach to prepare low toxic CdTe@ZnS QDs with stable fluorescence properties. To mitigate the risk of imprecise measurements stemming from the inherent susceptibility of fluorescence to quenching, we have adopted the principle of fluorescence resonance energy transfer (FRET) for the construction of the turn-on quantum dot sensor. With a detection limit for chlorpyrifos as low as 10 ppb (10 µg/L), the QDs sensor exhibits notable resistance to interference from various pesticides. Application of this system to detect organophosphorothioate pesticides in apples produced results consistent with those obtained from high-performance liquid chromatography (HPLC) detection, affirming the promising application prospects of this sensing system for the rapid detection of OPPs residues.
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Compostos de Cádmio , Transferência Ressonante de Energia de Fluorescência , Compostos Organofosforados , Praguicidas , Pontos Quânticos , Sulfetos , Telúrio , Compostos de Zinco , Pontos Quânticos/química , Compostos de Cádmio/química , Compostos de Zinco/química , Praguicidas/análise , Sulfetos/química , Transferência Ressonante de Energia de Fluorescência/métodos , Telúrio/química , Compostos Organofosforados/análise , Limite de Detecção , Malus/química , Clorpirifos/análise , Contaminação de Alimentos/análiseRESUMO
Objective To investigate the clinical efficacy and safety of the combination therapy of multi-targeted small molecule tyrosine kinase inhibitors(MTKIs)with immune checkpoint inhibitors(ICIs)for late-stage solid tumor in the patients with failed standard treatment regimens.Methods The patients with advanced solid tumors who had been hospitalized in our hospital from January 2021 to January 2023 after failure of≥2 standard treatment regimens were selected and treated with MTKIs combined with ICIs.The efficacy and safety of this regimen were retrospectively studied.Results A total of 21 patients were included.As of March 1,2022,the overall popula-tion had an ORR of 38%,a DCR of 67%,a median progression free survival(mPFS)of 10 months,and a median survival(mOS)of 15 months.Common adverse reactions were pneumonia and oral ulcers.Conclusion For the patients with advanced solid tumors who have failed standard treatment,MTKIs combined with ICIs may be a treat-ment option,but prospective studies with a larger sample size are needed to confirm the efficacy and safety of this combination therapy and to explore the population most likely to benefit from this treatment method.
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AIM:Bone morphogenetic protein 7(BMP7)reduces the expression of Yes-related protein 1(YAP1)by down-regulating Ajuba level and decreasing extracellular matrix(ECM)deposition.This study aimed to inves-tigate the influence of these factors on modifying the degree of renal fibrosis in rats with diabetic nephropathy.METH-ODS:Eighteen Sprague-Dawley(SD)rats were randomly divided into three groups:the normal control(NC)group,the diabetes mellitus(DM)group,and the DM group treated with BMP7 overexpressing adeno-associated virus(DM+rAAV-BMP7).Each group consisted of six rats.Diabetic kidney disease(DKD)was established in the DM and DM+rAAV-BMP7 groups by injecting 55 mg/kg streptozotocin(STZ)via the tail vein.NRK-52E cells were divided into three groups:the normal glucose(NG)group,the high glucose(HG)group,and the high glucose group treated with recombinant hu-man BMP7(HG+rhBMP7)group.Pathological changes in renal tissues were observed using hematoxylin and eosin(HE)and Sirius red staining.Immunohistochemical staining was performed to examine the expression sites of Ajuba and YAP1 in the renal cortex.Western blot analysis was conducted to determine the expression levels of BMP7,Ajuba,YAP1,colla-gen type Ⅲ(Col-Ⅲ),and fibronectin(FN)in the rat renal cortex and NRK-52E cells.RT-qPCR was used to measure the mRNA levels of Ajuba and YAP1 in the rat renal cortex.RESULTS:Biochemical indices revealed significantly ele-vated levels of blood glucose,serum creatinine,triglycerides,total cholesterol,and 24-hour urinary protein in the DM group compared to the NC group(P<0.05).In the DM+rAAV-BMP7 group,the levels of serum creatinine,24-hour uri-nary protein,triglycerides,and total cholesterol were lower than those in the DM group(P<0.05).Pathological staining demonstrated that the renal interstitium of the DM group exhibited inflammatory cell infiltration,fibrous tissue,collagen fi-ber deposition,disordered renal tubule arrangement,atrophy,and vacuolar degeneration,which were ameliorated in the DM+rAAV-BMP7 group.Immunohistochemistry revealed that Ajuba and YAP1 were mainly expressed in the cytoplasm and nucleus,with high expression in the cytoplasm of the DM group,which was significantly decreased in the DM+rAAV-BMP7 group.Western blot results indicated that the protein levels of FN,Col-Ⅲ,Ajuba,and YAP1 were up-regulated in the DM and the HG groups(P<0.05),but significantly down-regulated in the DM+rAAV-BMP7 group(P<0.05).RT-qP-CR results demonstrated that the mRNA levels of Ajuba and YAP1 were higher in the DM group and significantly lower in the DM+rAAV-BMP7 group(P<0.05).CONCLUSION:The overexpression of BMP7 can ameliorate renal fibrosis in rats with DKD.This effect is likely mediated by the down-regulation of Ajuba,reduction of YAP1 expression,and subse-quent inhibition of ECM deposition.
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Alzheimer's disease (AD) is the primary cause of dementia and is anticipated to impose a substantial economic burden in the future. Over a significant period, the widely accepted amyloid cascade hypothesis has guided research efforts, and the recent FDA approval of an anti- amyloid-beta (Aß) protofibrils antibody, believed to decelerate AD progression, has further solidified its significance. However, the excessive emphasis placed on the amyloid cascade hypothesis has overshadowed the physiological nature of Aß and tau proteins within axons. Axons, specialized neuronal structures, sustain damage during the early stages of AD, exerting a pivotal influence on disease progression. In this review, we present a comprehensive summary of the relationship between axonal damage and AD pathology, amalgamating the physiological roles of Aß and tau proteins, along with the impact of AD risk genes such as APOE and TREM2. Furthermore, we underscore the exceptional significance of axonal damage in the context of AD.
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BACKGROUND AND AIMS: Magnifying image-enhanced endoscopy (MIEE) is an advanced endoscopy with image enhancement and magnification used in preoperative examination. However, its impact on the detection rate is unknown. METHODS: We conducted an open-label, randomized, parallel (1:1:1), controlled trial in 6 hospitals in China. Patients were recruited between February 14, 2022 and July 30, 2022. Eligible patients were aged ≥18 years and undergoing gastroscopy in outpatient departments. Participants were randomly assigned to the MIEE-only mode (o-MIEE) group, white-light endoscopy-only mode (o-WLE) group, and MIEE when necessary mode (n-MIEE) group (initial WLE followed by switching to another endoscope with MIEE if necessary). Biopsy sampling of suspicious lesions of the lesser curvature of the gastric antrum was performed. Primary and secondary aims were to compare detection rates and positive predictive value (PPV) of early cancer and precancerous lesions in these 3 modes, respectively. RESULTS: A total of 5100 recruited patients were randomly assigned to the o-MIEE (n = 1700), o-WLE (n = 1700), and n-MIEE (n = 1700) groups. In the o-MIEE, o-WLE, and n-MIEE groups, 29 (1.51%; 95% confidence interval [CI], 1.05-2.16), 4 (.21%; 95% CI, .08-.54), and 8 (.43%; 95% CI, .22-.85) early cancers were found, respectively (P < .001). The PPV for early cancer was higher in the o-MIEE group compared with the o-WLE and n-MIEE groups (63.04%, 33.33%, and 38.1%, respectively; P = .062). The same trend was seen for precancerous lesions (36.67%, 10.00%, and 21.74%, respectively). CONCLUSIONS: The o-MIEE mode resulted in a significant improvement in diagnosing early upper GI cancer and precancerous lesions; thus, it could be used for opportunistic screening. (Clinical trial registration number: ChiCTR2200064174.).
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Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Adolescente , Adulto , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Lesões Pré-Cancerosas/diagnóstico por imagem , Lesões Pré-Cancerosas/patologia , Gastroscopia/métodos , Valor Preditivo dos Testes , BiópsiaRESUMO
Wireless sensor network nodes are widely used in wearable devices, consumer electronics, and industrial electronics and are a crucial component of the Internet of Things (IoT). Recently, advanced power technology with sustainable energy supply and pollution-free characteristics has become a popular research focus. Herein, to realize an unattended and reliable power supply unit suitable for distributed IoT systems, we develop a high-performance triboelectric-electromagnetic hybrid nanogenerator (TEHNG) to harvest mechanical energy. The TEHNG achieves a high load power of 21.8 mW by implementing improvements of material optimization, configuration optimization and pyramid microstructure design. To realize a self-powered integrated microsystem, a power management module, energy storage module, sensing signal processing module, and microcontroller unit are integrated into the TEHNG. Furthermore, an all-in-one wireless multisensing microsystem comprising the TEHNG, the abovementioned integrated functional circuit and three sensors (temperature, pressure, and ultraviolet) is built. The milliwatt microsystem operates continuously with the TEHNG as the only power supply, achieving self-powered operations of sensing environmental variables and transmitting wireless data to a terminal in real time. This shows tremendous application potential in the IoT field.
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Self-assembly is an important bottom-up fabrication approach based on accurate manipulation of solid-air-liquid interfaces to construct microscale structures using nanoscale materials. This approach plays a substantial role in the fabrication of microsensors, nanosensors, and actuators. Improving the controllability of self-assembly to realize large-scale regular micro/nano patterns is crucial for this approach's further development and wider applications. Herein, we propose a novel strategy for patterning nanoparticle arrays on soft substrates. This strategy is based on a unique process of liquid film rupture self-assembly that is convenient, precise, and cost-efficient for mass manufacturing. This approach involves two key steps. First, suspended liquid films comprising monolayer polystyrene (PS) spheres are realized via liquid-air interface self-assembly over prepatterned microstructures. Second, these suspended liquid films are ruptured in a controlled manner to induce the self-assembly of internal PS spheres around the morphological edges of the underlying microstructures. This nanoparticle array patterning method is comprehensively investigated in terms of the effect of the PS sphere size, morphological effect of the microstructured substrate, key factors influencing liquid film-rupture self-assembly, and optical transmittance of the fabricated samples. A maximum rupture rate of 95.4% was achieved with an optimized geometric and dimensional design. Compared with other nanoparticle-based self-assembly methods used to form patterned arrays, the proposed approach reduces the waste of nanoparticles substantially because all nanoparticles self-assemble around the prepatterned microstructures. More nanoparticles assemble to form prepatterned arrays, which could strengthen the nanoparticle array network without affecting the initial features of prepatterned microstructures.
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The practical applications of MgH2 as a high-density hydrogen carrier depend heavily on efficient and low-cost catalysts to accelerate the dehydriding/hydriding reactions at moderate temperatures. In the present work, this issue is addressed by synthesizing Nb-doped TiO2 solid-solution-type catalysts that dramatically improve the hydrogen sorption performances of MgH2. The catalyzed MgH2 can absorb 5 wt % of H2 even at room temperature for 20 s, release 6 wt % of H2 at 225 °C within 12 min, and the complete dehydrogenation can be achieved at 150 °C under a dynamic vacuum atmosphere. Density functional theory calculations reveal that Nb doping introduces Nb 4d orbitals with stronger interaction with H 1s into the density of states of TiO2. This considerably enhances both the adsorption and dissociation ability of the H2 molecule on the catalysts surface and the hydrogen diffusion across the specific Mg/Ti(Nb)O2 interface. The successful implementation of solid solution-type catalysts in MgH2 offers a demonstration and inspiration for the development of high-performance catalysts and solid-state hydrogen storage materials.
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Objective:To assess the clinical effectiveness and safety of Omalizumab for treating pediatric allergic asthma in real world in China.Methods:The clinical data of children aged 6 to 11 years with allergic asthma who received Omalizumab treatment in 17 hospitals in China between July 6, 2018 and September 30, 2020 were retrospectively analyzed.Such information as the demographic characteristics, allergic history, family history, total immunoglobulin E (IgE) levels, specific IgE levels, skin prick test, exhaled nitric oxide (FeNO) levels, eosinophil (EOS) counts, and comorbidities at baseline were collected.Descriptive analysis of the Omalizumab treatment mode was made, and the difference in the first dose, injection frequency and course of treatment between the Omalizumab treatment mode and the mode recommended in the instruction was investigated.Global Evaluation of Treatment Effectiveness (GETE) analysis was made after Omalizumab treatment.The moderate-to-severe asthma exacerbation rate, inhaled corticosteroid (ICS) dose, lung functions were compared before and after Omalizumab treatment.Changes in the Childhood Asthma Control Test (C-ACT) and Pediatric Asthma Quality of Life Questionnaire (PAQLQ) results from baseline to 4, 8, 12, 16, 24, and 52 weeks after Omalizumab treatment were studied.The commodity improvement was assessed.The adverse event (AE) and serious adverse event (SAE) were analyzed for the evaluation of Omalizumab treatment safety.The difference in the annual rate of moderate-to-severe asthma exacerbation and ICS reduction was investigated by using t test.The significance level was set to 0.05.Other parameters were all subject to descriptive analysis.A total of 200 allergic asthma patients were enrolled, including 75.5% ( n=151) males and 24.5% ( n=49) females.The patients aged (8.20±1.81) years. Results:The median total IgE level of the 200 patients was 513.5 (24.4-11 600.0) IU/mL.Their median treatment time with Omalizumab was 112 (1-666) days.Their first dose of Omalizumab was 300 (150-600) mg.Of the 200 cases, 114 cases (57.0%) followed the first Omalizumab dosage recommended in the instruction.After 4-6 months of Omalizumab treatment, 88.5% of the patients enrolled ( n=117) responded to Omalizumab.After 4 weeks of treatment with Omalizumab, asthma was well-controlled, with an increased C-ACT score [from (22.70±3.70) points to (18.90±3.74) points at baseline]. Four-six months after Omalizumab administration, the annual rate of moderate-to-severe asthma exacerbation had a reduction of (2.00±5.68) per patient year( t=4.702 5, P<0.001), the median ICS daily dose was lowered [0 (0-240) μg vs. 160 (50-4 000) μg at baseline] ( P<0.001), the PAQLQ score was improved [(154.90±8.57) points vs. (122.80±27.15) points at baseline], and the forced expiratory volume in one second % predicted (FEV 1%pred) was increased [(92.80±10.50)% vs. (89.70±18.17)% at baseline]. In patients with available evaluations for comorbidities, including allergic rhinitis, atopic dermatitis or eczema, urticaria, allergic conjunctivitis and sinusitis, 92.8%-100.0% showed improved symptoms.A total of 124 AE were reported in 58 (29.0%) of the 200 patients, and the annual incidence was 0(0-15.1) per patient year.In 53 patients who suffered AE, 44 patients (83.0%) and 9 patients (17.0%) reported mild and moderate AE, respectively.No severe AE were observed in patients.The annual incidence of SAE was 0(0-1.9) per patient year.Most common drug-related AE were abdominal pain (2 patients, 1.0%) and fever (2 patients, 1.0%). No patient withdrew Omalizumab due to AE. Conclusions:Omalizumab shows good effectiveness and safety for the treatment of asthma in children.It can reduce the moderate-to-severe asthma exacerbation rate, reduce the ICS dose, improve asthma control levels, and improve lung functions and quality of life of patients.
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OBJECTIVES@#To investigate the risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture and establish a nomogram model for predicting the risk of neonatal asphyxia.@*METHODS@#A retrospective study was conducted with 613 cases of neonatal asphyxia treated in 20 cooperative hospitals in Enshi Tujia and Miao Autonomous Prefecture from January to December 2019 as the asphyxia group, and 988 randomly selected non-asphyxia neonates born and admitted to the neonatology department of these hospitals during the same period as the control group. Univariate and multivariate analyses were used to identify risk factors for neonatal asphyxia. R software (4.2.2) was used to establish a nomogram model. Receiver operator characteristic curve, calibration curve, and decision curve analysis were used to assess the discrimination, calibration, and clinical usefulness of the model for predicting the risk of neonatal asphyxia, respectively.@*RESULTS@#Multivariate logistic regression analysis showed that minority (Tujia), male sex, premature birth, congenital malformations, abnormal fetal position, intrauterine distress, maternal occupation as a farmer, education level below high school, fewer than 9 prenatal check-ups, threatened abortion, abnormal umbilical cord, abnormal amniotic fluid, placenta previa, abruptio placentae, emergency caesarean section, and assisted delivery were independent risk factors for neonatal asphyxia (P<0.05). The area under the curve of the model for predicting the risk of neonatal asphyxia based on these risk factors was 0.748 (95%CI: 0.723-0.772). The calibration curve indicated high accuracy of the model for predicting the risk of neonatal asphyxia. The decision curve analysis showed that the model could provide a higher net benefit for neonates at risk of asphyxia.@*CONCLUSIONS@#The risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture are multifactorial, and the nomogram model based on these factors has good value in predicting the risk of neonatal asphyxia, which can help clinicians identify neonates at high risk of asphyxia early, and reduce the incidence of neonatal asphyxia.
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Recém-Nascido , Humanos , Masculino , Gravidez , Feminino , Nomogramas , Estudos Retrospectivos , Cesárea , Fatores de Risco , Asfixia Neonatal/etiologiaRESUMO
EGFR G724S mutation in exon 18 has been shown to be resistant to both first- and third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). However, we found a rare mutation of EGFR Ex19del/G724S in two patients with lung cancer who demonstrated a favorable response to the combination of afatinib and chemotherapy. Identified by next-generation sequencing (NGS), EGFR G724S was found from a primary and a secondary tumor biopsy, respectively. Treated with afatinib combined with chemotherapy, both patients responded well and achieved progression-free survival. Analysis of acquired mutations developed during treatment using afatinib revealed that the emergence of EGFR T790M or ALK fusion was the potential mechanism of afatinib resistance. Our study lends credence to treatment using afatinib combined with chemotherapy as a viable option for patients with Ex19del/G724S.
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Wearable electronics with development trends such as miniaturization, multifunction, and smart integration have become an important part of the Internet of Things (IoT) and have penetrated various sectors of modern society. To meet the increasing demands of wearable electronics in terms of deformability and conformability, many efforts have been devoted to overcoming the nonstretchable and poor conformal properties of traditional functional materials and endowing devices with outstanding mechanical properties. One of the promising approaches is composite engineering in which traditional functional materials are incorporated into the various polymer matrices to develop different kinds of functional composites and construct different functions of stretchable electronics. Herein, we focus on the approach of composite engineering and the polymer matrix of silicone rubber (SR), and we summarize the state-of-the-art details of silicone rubber-based conductive composites (SRCCs), including a summary of their conductivity mechanisms and synthesis methods and SRCC applications for stretchable electronics. For conductivity mechanisms, two conductivity mechanisms of SRCC are emphasized: percolation theory and the quantum tunneling mechanism. For synthesis methods of SRCCs, four typical approaches to synthesize different kinds of SRCCs are investigated: mixing/blending, infiltration, ion implantation, and in situ formation. For SRCC applications, different functions of stretchable electronics based on SRCCs for interconnecting, sensing, powering, actuating, and transmitting are summarized, including stretchable interconnects, sensors, nanogenerators, antennas, and transistors. These functions reveal the feasibility of constructing a stretchable all-in-one self-powered microsystem based on SRCC-based stretchable electronics. As a prospect, this microsystem is expected to integrate the functional sensing modulus, the energy harvesting modulus, and the process and response modulus together to sense and respond to environmental stimulations and human physiological signals.
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Wearable electronics, as essential components of the Internet of Things (IoT), have attracted widespread attention, and the trend is to configure attractive wearable smart microsystems by integrating sensing, powering, and other functions. Herein, we developed an elastic hybrid triboelectric-electromagnetic microenergy harvester (named EHTE) to realize hybrid sensing and microenergy simultaneously. This EHTE is a highly integrated triboelectric nanogenerator (TENG) and electromagnetic nanogenerator (EMG). Based on the triboelectric-electromagnetic hybrid mechanism, an enhanced electrical output of the EHTE was achieved successfully, which demonstrates the feasibility of the EHTE for microelectronics powering. Moreover, with the merits of the EMG, the developed hybrid microenergy harvester integrated both active frequency sensing and passive inductive sensing capabilities. Specifically, the almost linear correlation of the electromagnetic outputs to the frequencies of the external stimulus endowed the proposed EHTE with an outstanding active frequency sensing ability. In addition, due to the unique structural configuration of the EMG (i.e., a conductive permanent magnet (PM), hybrid deformation layer, and flexible printed circuit board (FPCB) coil), an opportunity was provided for the developed EHTE to serve as a passive inductive sensor based on the eddy current effect (i.e., a form of electromagnetic induction). Therefore, the developed EHTE successfully achieved the integration of hybrid sensing (i.e., active frequency sensing and passive inductive sensing) and microenergy (i.e., the combination of electromagnetic effect and triboelectric effect) within a single device, which demonstrates the potential of this newly developed EHTE for wearable electronic applications, especially in applications of compact active microsystems.
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In recent years, considerable research efforts have been devoted to the development of wearable multi-functional sensing technology to fulfill the requirements of healthcare smart detection, and much progress has been achieved. Due to the appealing characteristics of flexibility, stretchability and long-term stability, the sensors have been used in a wide range of applications, such as respiration monitoring, pulse wave detection, gait pattern analysis, etc. Wearable sensors based on single mechanisms are usually capable of sensing only one physiological or motion signal. In order to measure, record and analyze comprehensive physical conditions, it is indispensable to explore the wearable sensors based on hybrid mechanisms and realize the integration of multiple smart functions. Herein, we have summarized various working mechanisms (resistive, capacitive, triboelectric, piezoelectric, thermo-electric, pyroelectric) and hybrid mechanisms that are incorporated into wearable sensors. More importantly, to make wearable sensors work persistently, it is meaningful to combine flexible power units and wearable sensors and form a self-powered system. This article also emphasizes the utility of self-powered wearable sensors from the perspective of mechanisms, and gives applications. Furthermore, we discuss the emerging materials and structures that are applied to achieve high sensitivity. In the end, we present perspectives on the outlooks of wearable multi-functional sensing technology.
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Objective@#The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been engendering enormous hazards to the world. We obtained the complete genome sequences of SARS-CoV-2 from imported cases admitted to the Guangzhou Eighth People's Hospital, which was appointed by the Guangdong provincial government to treat coronavirus disease 2019 (COVID-19). The SARS-CoV-2 diversity was analyzed, and the mutation characteristics, time, and regional trend of variant emergence were evaluated.@*Methods@#In total, 177 throat swab samples were obtained from COVID-19 patients (from October 2020 to May 2021). High-throughput sequencing technology was used to detect the viral sequences of patients infected with SARS-CoV-2. Phylogenetic and molecular evolutionary analyses were used to evaluate the mutation characteristics and the time and regional trends of variants.@*Results@#We observed that the imported cases mainly occurred after January 2021, peaking in May 2021, with the highest proportion observed from cases originating from the United States. The main lineages were found in Europe, Africa, and North America, and B.1.1.7 and B.1.351 were the two major sublineages. Sublineage B.1.618 was the Asian lineage (Indian) found in this study, and B.1.1.228 was not included in the lineage list of the Pangolin web. A reasonably high homology was observed among all samples. The total frequency of mutations showed that the open reading frame 1a (ORF1a) protein had the highest mutation density at the nucleotide level, and the D614G mutation in the spike protein was the commonest at the amino acid level. Most importantly, we identified some amino acid mutations in positions S, ORF7b, and ORF9b, and they have neither been reported on the Global Initiative of Sharing All Influenza Data nor published in PubMed among all missense mutations.@*Conclusion@#These results suggested the diversity of lineages and sublineages and the high homology at the amino acid level among imported cases infected with SARS-CoV-2 in Guangdong Province, China.
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Humanos , Aminoácidos , COVID-19/epidemiologia , Genômica , Mutação , Filogenia , SARS-CoV-2/genéticaRESUMO
Recently, triboelectric nanogenerators (TENGs) have been promoted as an effective technique for ambient energy harvesting, given their large power density and high energy conversion efficiency. However, traditional TENGs based on the combination of triboelectrification effect and electrostatic induction have proven susceptible to environmental influence, which intensively restricts their application range. Herein, a new coupling mechanism based on electrostatic induction and ion conduction is proposed to construct flexible stable output performance TENGs (SOP-TENGs). The calcium chloride doped-cellulose nanofibril (CaCl2-CNF) film made of natural carrots was successfully introduced to realize this coupling, resulting from its intrinsic properties as natural nanofibril hydrogel serving as both triboelectric layer and electrode. The coupling of two conductive mechanisms of SOP-TENG was comprehensively investigated through electrical measurements, including the effects of moisture content, relative humidity, and electrode size. In contrast to the conventional hydrogel ionotronic TENGs that require moisture as the carrier for ion transfer and use a hydrogel layer as the electrode, the use of a CaCl2-CNF film (i.e., ion-doped natural hydrogel layer) as a friction layer in the proposed SOP-TENG effectively realizes a superstable electrical output under varying moisture contents and relative humidity due to the compound transfer mechanism of ions and electrons. This new working principle based on the coupling of electrostatic induction and ion conduction opens a wider range of applications for the hydrogel ionotronic TENGs, as the superstable electrical output enables them to be more widely applied in various complex environments to supply energy for low-power electronic devices.
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With the rapid development of the Internet of Things (IoT) and the emergence of 5G, traditional silicon-based electronics no longer fully meet market demands such as nonplanar application scenarios due to mechanical mismatch. This provides unprecedented opportunities for flexible electronics that bypass the physical rigidity through the introduction of flexible materials. In recent decades, biological materials with outstanding biocompatibility and biodegradability, which are considered some of the most promising candidates for next-generation flexible electronics, have received increasing attention, e.g., silk fibroin, cellulose, pectin, chitosan, and melanin. Among them, silk fibroin presents greater superiorities in biocompatibility and biodegradability, and moreover, it also possesses a variety of attractive properties, such as adjustable water solubility, remarkable optical transmittance, high mechanical robustness, light weight, and ease of processing, which are partially or even completely lacking in other biological materials. Therefore, silk fibroin has been widely used as fundamental components for the construction of biocompatible flexible electronics, particularly for wearable and implantable devices. Furthermore, in recent years, more attention has been paid to the investigation of the functional characteristics of silk fibroin, such as the dielectric properties, piezoelectric properties, strong ability to lose electrons, and sensitivity to environmental variables. Here, this paper not only reviews the preparation technologies for various forms of silk fibroin and the recent progress in the use of silk fibroin as a fundamental material but also focuses on the recent advanced works in which silk fibroin serves as functional components. Additionally, the challenges and future development of silk fibroin-based flexible electronics are summarized. (1) This review focuses on silk fibroin serving as active functional components to construct flexible electronics. (2) Recent representative reports on flexible electronic devices that applied silk fibroin as fundamental supporting components are summarized. (3) This review summarizes the current typical silk fibroin-based materials and the corresponding advanced preparation technologies. (4) The current challenges and future development of silk fibroin-based flexible electronic devices are analyzed.
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The COVID-19 pandemic and the SARS-CoV-2 with its variants have posed unprecedented challenges worldwide. Existing vaccines have limited effectiveness against the SARS-CoV-2 variants. Therefore, novel vaccines to match current mutated viral lineages with long-term protective immunity are urgently in demand. In the current study, we for the first time designed a recombinant Adeno-Associated Virus 5 (rAAV5)-based vaccine named as rAAV-COVID-19 vaccine (Covacinplus) by using RBD-plus of spike protein with both the single-stranded and the self-complementary AAV5 delivering vectors (ssAAV5 and scAAAV5), which provides excellent protection from SARS-CoV-2 infection. A single dose vaccination induced the strong immune response against SARS-CoV-2. The induced neutralizing antibodies (NAs) titers were maintained at a high peak level of over 1:1024 even after more than one year of injection and accompanied with functional T-cells responses in mice. Importantly, both ssAAV- and scAAV-based RBD-plus vaccines exhibited high levels of serum NAs against current circulating variants including variants Alpha, Beta, Gamma and Delta. SARS-CoV-2 virus challenge test showed that ssAAV5-RBD-plus vaccine protected both young and old age mice from SARS-CoV-2 infection in the upper and the lower respiratory tracts. Moreover, whole genome sequencing demonstrated that AAV vector DNA sequences were not found in the genome of the vaccinated mice after one year vaccination, demonstrating excellent safety of the vaccine. Taken together, this study suggests that rAAV5-based vaccine is powerful against SARS-CoV-2 and its variants with long-term protective immunity and excellent safety, which has great potential for development into prophylactic vaccination in human to end this global pandemic.
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Wearable electronic devices have great potential in the fields of the Internet of Things (IoT), sports and entertainment, and healthcare, and they are essential in advancing the development of next-generation electronic information technology. However, conventional lithium batteries, which are currently the main power supply of wearable electronic devices, have some critical issues, such as frequent charging, environmental pollution, and no surface adaptability, which limit the further development of wearable electronic devices. To address these challenges, we present a flexible hybrid photothermoelectric generator (PTEG) with a simple structure composed of a thermoelectric generator (TEG) and a light-to-thermal conversion layer to simultaneously harvest thermal and radiation energies based on a single working mechanism. The mature mass-fabrication technology of screen printing was applied to successively prepare n-type (i.e., Bi2Te2.7Se0.3) and p-type (i.e., Sb2Te3) thermoelectric inks atop a polyimide substrate to form the TEG with a serpentine thermocouple chain, which was further covered by a light-to-thermal conversion layer to constitute the PTEG. The resulting PTEG with five pairs of thermocouples generated a direct-current output of 82.4 mV at a temperature difference of 50 °C and a direct-current output of 41.2 mV under 20 mW/cm2 infrared radiation. Meanwhile, the remarkable mechanical reliability and output stability were experimentally demonstrated through a systematic test, which indicated the feasibility and potential of the developed PTEG as a reliable power source. In addition, as desirable application prototypes, the fabricated PTEGs have been successfully demonstrated to harvest biothermal energy and infrared radiation to drive portable electronic devices (e.g., a calculator and a clock). Hybrid energy harvesting technology based on a simple structure may provide a new solution to current power supply issues of wearable electronic device.
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In recent years, wearable electronic devices have made considerable progress thanks to the rapid development of the Internet of Things. However, even though some of them have preliminarily achieved miniaturization and wearability, the drawbacks of frequent charging and physical rigidity of conventional lithium batteries, which are currently the most commonly used power source of wearable electronic devices, have become technical bottlenecks that need to be broken through urgently. In order to address the above challenges, the technology based on triboelectric effect, i.e., triboelectric nanogenerator (TENG), is proposed to harvest energy from ambient environment and considered as one of the most promising methods to integrate with functional electronic devices to form wearable self-powered microsystems. Benefited from excellent flexibility, high output performance, no materials limitation, and a quantitative relationship between environmental stimulation inputs and corresponding electrical outputs, TENGs present great advantages in wearable energy harvesting, active sensing, and driving actuators. Furthermore, combined with the superiorities of TENGs and fabrics, textile-based TENGs (T-TENGs) possess remarkable breathability and better non-planar surface adaptability, which are more conducive to the integrated wearable electronic devices and attract considerable attention. Herein, for the purpose of advancing the development of wearable electronic devices, this article reviews the recent development in materials for the construction of T-TENGs and methods for the enhancement of electrical output performance. More importantly, this article mainly focuses on the recent representative work, in which T-TENGs-based active sensors, T-TENGs-based self-driven actuators, and T-TENGs-based self-powered microsystems are studied. In addition, this paper summarizes the critical challenges and future opportunities of T-TENG-based wearable integrated microsystems.