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Y900 is one of the top hybrid rice (Oryza sativa) varieties, with its yield exceeding 15 t·hm-2. To dissect the mechanism of heterosis, we sequenced the male parent line R900 and female parent line Y58S using long-read and Hi-C technology. High-quality reference genomes of 396.41 Mb and 398.24 Mb were obtained for R900 and Y58S, respectively. Genome-wide variations between the parents were systematically identified, including 1,367,758 single-nucleotide polymorphisms, 299,149 insertions/deletions, and 4,757 structural variations. The level of variation between Y58S and R900 was the lowest among the comparisons of Y58S with other rice genomes. More than 75% of genes exhibited variation between the two parents. Compared with other two-line hybrids sharing the same female parent, the portion of Geng/japonica (GJ)-type genetic components from different male parents increased with yield increasing in their corresponding hybrids. Transcriptome analysis revealed that the partial dominance effect was the main genetic effect that constituted the heterosis of Y900. In the hybrid, both alleles from the two parents were expressed, and their expression patterns were dynamically regulated in different tissues. The cis-regulation was dominant for young panicle tissues, while trans-regulation was more common in leaf tissues. Overdominance was surprisingly prevalent in stems and more likely regulated by the trans-regulation mechanism. Additionally, R900 contained many excellent GJ haplotypes, such as NARROW LEAF1, Oryza sativa SQUAMOSA PROMOTER BINDING PROTEIN-LIKE13, and Grain number, plant height, and heading date8, making it a good complement to Y58S. The fine-tuned mechanism of heterosis involves genome-wide variation, GJ introgression, key functional genes, and dynamic gene/allele expression and regulation pattern changes in different tissues and growth stages.
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Vigor Híbrido , Oryza , Vigor Híbrido/genética , Oryza/genética , Perfilação da Expressão Gênica , Hibridização GenéticaRESUMO
In Brief: The mechanisms that determine the length of pregnancy remain undetermined. Here, we review what has been previously published on the topic and incorporate new data to describe a molecular model in which placental stress and fetal signaling ultimately lead to labor onset in uncomplicated pregnancies. Abstract: The mechanisms that govern the length of human pregnancy have not been determined, while preterm birth remains the leading cause of death and disability in newborns worldwide. Here, we review recent data to generate a novel hypothesis about how the pregnancy clock may function to initiate human labor in uncomplicated pregnancies. In this model, placental stress induced by the growing fetus drives placental production of NFKB, which is then activated by exosomes containing platelet-activating factor and complement 4-binding protein-A from the mature fetus, to drive pro-labor genes in the placenta. A better understanding of the clock that triggers labor may lead to new, more effective therapies to prevent spontaneous preterm birth.
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Placenta , Humanos , Feminino , Gravidez , Placenta/metabolismo , Placenta/fisiologia , Relógios Biológicos , Nascimento Prematuro/metabolismo , Início do Trabalho de Parto/fisiologiaRESUMO
Superhydrophobic coatings are increasingly recognized as a promising approach to enhancing power generation efficiency and prolonging the operational lifespan of wind turbines. In this research, a durable superhydrophobic perfluoroalkoxy alkane (PFA) coating was developed and specifically designed for spray application onto the surface of wind turbine blades. The PFA coating features a micronano hierarchical structure, exhibiting a high water contact angle of 167.0° and a low sliding angle of 1.7°. The optimal PFA coating exhibits stability and maintains a superhydrophobic performance during mechanical and chemical tests. The findings of this study establish a positive association between the surface energy of the coating and its effectiveness in anti-icing. The delayed icing time for the PFA-coated surface is 46.83 times longer than that of an uncoated surface, and the ice adhesion strength is only 1.875 kPa. Additionally, the PFA coating demonstrates remarkably high ice suppression efficiencies of 94.7 and 99.5% in anti-icing experiments at ambient temperatures of -6 and -10 °C, respectively. It is anticipated that this stable superhydrophobic PFA coating will be a candidate for anti-icing applications in wind turbine blades.
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OBJECTIVE: To analyze the correlation between the level of 25(OH)D in peripheral blood and cognitive function in patients with epilepsy, and to find the biomarkers of epilepsy complicated with cognitive dysfunction. METHODS: 68 patients with epilepsy and 30 healthy subjects were included in this study. The 25(OH)D level in peripheral blood of all subjects was detected and the score of the Montreal Cognitive Assessment Scale was performed. The patients with epilepsy were divided into a cognitively normal group (36 cases) and a cognitively impaired group (32 cases) according to the scale score. The inter-group scale score and 25(OH)D level were compared, and the correlation was analyzed. RESULTS: The levels of 25(OH)D and MOCA in epileptic group were significantly lower than those in healthy control group. The 25(OH)D and MOCA of the cognitively impaired group were significantly lower than those of the cognitively normal group. Logistic regression analysis indicated that serum 25(OH)D level was an independent risk factor for epilepsy combined with cognitive impairment (OR = 0.704, P = 0.014). The area under ROC curve of serum 25(OH)D for diagnosis of epilepsy combined with cognitive impairment was 0.924 (95 %CI 0.866,0.981), the critical value was 34.50 nmol/L, the sensitivity was 0.778, and the specificity was 0.906. CONCLUSION: Decreased levels of vitamin D are associated with cognitive impairment associated with epilepsy, and it may be a biomarker for early screening of cognitive impairment.
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Constructing Z-scheme heterojunctions incorporating an exquisite hollow structure is an effective performance regulation strategy for the realization of high quantum efficiency and a strong redox ability over photocatalysts. Herein, we report the delicate design and preparation of a core-shell hollow CdS@CoTiO3 Z-scheme heterojunction with a CdS nanoparticle (NP)-constructed outer shell supported on a CoTiO3 nanorod (NR) inner shell. The in situ growth synthetic method led to a tightly connected interface for the heterojunction between CdS and CoTiO3, which shortened the transport distance of photoinduced charges from the interface to the surface. The promoted charge carrier separation efficiency and the retained strong redox capacity caused by the Z-scheme photoinduced charge-transfer mechanism were mainly responsible for the boosted photocatalytic performance. Additionally, the well-designed core-shell structure afforded a larger interfacial area by the multiple direction contact between CdS and CoTiO3, ensuring sufficient channels for efficient charge transfer, and thus further boosting the photocatalytic activity. As an efficient photocatalyst, the optimized CdS@CoTiO3 nanohybrids displayed excellent 2,4-dichlorophenol (2,4-DCP) and tetracycline (TC) degradation efficiencies of 91.3% and 91.8%, respectively. This study presents a Z-scheme heterojunction based on ecofriendly CoTiO3, which could be valuable for the development of metal perovskite photocatalysts for application in environmental remediation, and also demonstrated the tremendous potential of integrating a Z-scheme heterojunction with the morphology design of photocatalyts.
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BACKGROUND: Community-acquired pneumonia (CAP) patients with chronic obstructive pulmonary disease (COPD) have higher disease severity and mortality compared to those without COPD. However, deep investigation into microbiome distribution of lower respiratory tract of CAP with or without COPD was unknown. METHODS: So we used metagenomic next generation sequencing (mNGS) to explore the microbiome differences between the two groups. RESULTS: Thirty-six CAP without COPD and 11 CAP with COPD cases were retrieved. Bronchoalveolar lavage fluid (BALF) was collected and analyzed using untargeted mNGS and bioinformatic analysis. mNGS revealed that CAP with COPD group was abundant with Streptococcus, Prevotella, Bordetella at genus level and Cutibacterium acnes, Rothia mucilaginosa, Bordetella genomosp. 6 at species level. While CAP without COPD group was abundant with Ralstonia, Prevotella, Streptococcus at genus level and Ralstonia pickettii, Rothia mucilaginosa, Prevotella melaninogenica at species level. Meanwhile, both alpha and beta microbiome diversity was similar between groups. Linear discriminant analysis found that pa-raburkholderia, corynebacterium tuberculostearicum and staphylococcus hominis were more enriched in CAP without COPD group while the abundance of streptococcus intermedius, streptococcus constellatus, streptococcus milleri, fusarium was higher in CAP with COPD group. CONCLUSIONS: These findings revealed that concomitant COPD have an mild impact on lower airway microbiome of CAP patients.
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Líquido da Lavagem Broncoalveolar , Infecções Comunitárias Adquiridas , Metagenômica , Microbiota , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/microbiologia , Líquido da Lavagem Broncoalveolar/microbiologia , Infecções Comunitárias Adquiridas/microbiologia , Masculino , Estudos Retrospectivos , Idoso , Feminino , Microbiota/genética , Pessoa de Meia-Idade , Metagenômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Pneumonia/microbiologia , Idoso de 80 Anos ou maisRESUMO
OBJECTIVE: Pregnant women are at increased risk of coronavirus disease 2019 (COVID-19). This could be explained through the prism of physiologic and immunologic changes in pregnancy. In addition, certain immunological reactions originate in the placenta in response to viral infections.This study aimed to investigate whether severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) can infect the human placenta and discuss its implications in the pathogenesis of adverse pregnancy outcomes. STUDY DESIGN: We conducted a retrospective cohort study in which we collected placental specimens from pregnant women who had a laboratory-confirmed SARS-CoV-2 infection. We performed RNA in situ hybridization assay on formalin-fixed paraffin-embedded tissues to establish the in vivo evidence for placental infectivity by this corona virus. In addition, we infected trophoblast isolated from uninfected term human placenta with SARS-CoV-2 variants to further provide in vitro evidence for such an infectivity. RESULTS: There was a total of 21 cases enrolled, which included 5 cases of spontaneous preterm birth (SPTB) and 2 intrauterine fetal demises (IUFDs). Positive staining of positive-sense strand of SARS-CoV-2 virions was detected in 15 placentas including 4 SPTB and both IUFDs. In vitro infection assay demonstrated that SARS-CoV-2 virions were highly capable of infecting both cytotrophoblast and syncytiotrophoblast. CONCLUSION: This study implies that placental SARS-CoV-2 infection may be associated with an increased risk of adverse obstetrical outcomes. KEY POINTS: · SARS-CoV-2 can effectively infect human placenta.. · Such infectivity is confirmed by in vitro experiments.. · Placental SARS-CoV-2 corelates with adverse obstetrical outcomes..
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To analyse the risk factors affecting wound healing and infection after spinal meningioma resection surgery. The surgical incision healing of 137 patients who underwent spinal meningioma resection at our hospital from January 2021 to January 2024 was analysed. The data collected included physical examination findings, haematological and biochemical measurements, and various scales assessed upon admission and after surgery. These data were then analysed. The surgical wound healing, infection and postoperative complications were statistically analysed. Multiple logistic regression analysis method was used to conduct risk factor analysis on corresponding indicators; the odds ratio and p value of 95% confidence interval were calculated. Factors such as age and smoking history were significantly negatively correlated with wound healing after meningioma resection (odds ratio < 1.000, p < 0.05), while preoperative albumin and platelet count were significantly positively correlated with wound healing (odds ratio > 1.000, p < 0.05). Age, WHO Meningioma Grading, preoperative albumin and preoperative platelet were significantly negatively correlated with wound infection after meningioma resection (odds ratio < 1.000, p < 0.05). The history of virus infection and history of neurological disorders were significantly positively correlated with wound infection (odds ratio > 1.000, p < 0.05). The influence of each factor is different. Age, smoking history, WHO Meningioma Grading, preoperative albumin, preoperative platelets, history of virus infection and history of neurological disorders had the greatest influence on wound healing and infection after meningioma resection.
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Neoplasias Meníngeas , Meningioma , Ferida Cirúrgica , Viroses , Infecção dos Ferimentos , Humanos , Meningioma/cirurgia , Estudos Retrospectivos , Fatores de Risco , Cicatrização , Neoplasias Meníngeas/cirurgia , AlbuminasRESUMO
The trifluoromethyl (CF3) group is an essential moiety in medicinal chemistry due to its unique physicochemical properties. While trifluoroacetic acid (TFA) is an inexpensive and easily accessible reagent, its use as a source of CF3 is highly challenging due to its high oxidation potential. In this study, we present a novel electrophotochemical approach that enables the use of TFA as the CF3 source for the selective, catalyst- and oxidant-free trifluoromethylation of (hetero)arenes. Key to our approach is the selective oxidation of TFA over arenes, generating CF3 radicals through oxidative decarboxylation. This strategy enables the sustainable and environmentally-friendly synthesis of CF3-, CF2H- and perfluoroalkyl-containing (hetero)arenes with a broad range of substrates. Importantly, our results demonstrate significantly improved chemoselectivity by light irradiation, opening up new possibilities for the synthetic and medicinal applications of TFA as an ideal yet underutilized CF3 source.
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Optical frequency combs with more than 10 W have paved the way for extreme ultraviolet combs generation by interaction with inert gases, leading to extreme nonlinear spectroscopy and the ultraviolet nuclear clock. Recently, the demand for an ultra-long-distance time and frequency space transfer via optical dual-comb proposes a new challenge for high power frequency comb in respect of power scaling and optical frequency stability. Here we present a frequency comb based on fiber chirped pulse amplification (CPA), which can offer more than 20 W output power. We further characterize the amplifier branch noise contribution by comparing two methods of locking to an optical reference and measure the out-of-loop frequency instability by heterodyning two identical high-power combs. Thanks to the low noise CPA, reasonable locking method, and optical path-controlled amplifiers, the out-of-loop beat note between two combs demonstrates the unprecedented frequency stability of 4.35 × 10-17 at 1s and 6.54 × 10-19 at 1000 s.
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The reprocessing of spent nuclear fuel is critical for the sustainability of the nuclear energy industry. However, several key separation processes present challenges in this regard, calling for continuous research into next-generation separation materials. Herein, we propose a high-throughput screening framework to improve efficiency in identifying potential ligands that selectively coordinate metal cations of interest in liquid wastes that considers multiple key chemical characteristics, including aqueous solubility, pKa, and coordination bond length. Machine-learning models were designed for the fast and accurate prediction of these characteristics by using graph convolution and transfer-learning techniques. Suitable ligands for Cs/Sr crystallizing separation were identified through the "computational funnel", and several top-ranking, nontoxic, low-cost ligands were selected for experimental verification.
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L-tryptophan (L-trp), produced through bio-manufacturing, is widely used in the pharmaceutical and food industries. Based on the previously developed L-trp-producing strain, this study significantly improved the titer and yield of L-trp, through metabolic engineering of the shikimate pathway and the L-tryptophan branch. First, the rate-limiting steps in the shikimate pathway were investigated and deciphered, revealing that the combined overexpression of the genes aroE and aroD increased L-trp production. Then, L-trp synthesis was further enhanced at the shaking flask level by improving the intracellular availability of L-glutamine (L-gln) and L-serine (L-ser). In addition, the transport system and the competing pathway of L-trp were also modified, indicating that elimination of the gene TnaB contributed to the extracellular accumulation of L-trp. Through optimizing formulas, the robustness and production efficiency of engineered strains were enhanced at the level of the 30 L fermenter. After 42 h of fed-batch fermentation, the resultant strain produced 53.65 g/L of L-trp, with a yield of 0.238 g/g glucose. In this study, the high-efficiency L-trp-producing strains were created in order to establish a basis for further development of more strains for the production of other highly valuable aromatic compounds or their derivatives.
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Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Triptofano/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Engenharia Metabólica , FermentaçãoRESUMO
Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources, chemical mechanisms, and transport processes of air pollution in land, sea, and atmosphere. We present an overview of coastal ocean boundary layer detection technology and equipment in China and summarize the progress and main achievements in recent years. China has developed a series of coastal ocean boundary layer detection technologies, including Light Detection and Ranging (LIDAR), turbulent exchange analyzer, air-sea flux analyzer, stereoscopic remote sensing of air pollutants, and oceanic aerosol detection equipment to address the technical bottleneck caused by harsh environmental conditions in coastal ocean regions. Advances in these technologies and equipment have provided scientific assistance for addressing air pollution issues and understanding land-sea-atmosphere interactions over coastal ocean regions in China. In the future, routine atmospheric observations should cover the coastal ocean boundary layer of China.
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Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Oceanos e Mares , Tecnologia , ChinaRESUMO
This report describes the unprecedented electrooxidation of a solvent (e.g., DMF)-ligated B2 cat2 complex, whereby a solvent-stabilized boryl radical is formed via quasi-homolytic cleavage of the B-B bond in a DMF-ligated B2 cat2 radical cation. Cyclic voltammetry and density functional theory provide evidence to support this novel B-B bond activation strategy. Furthermore, a strategy for the electrochemical gem-diborylation of gem-bromides via paired electrolysis is developed for the first time, affording a range of versatile gem-diborylalkanes, which are widely used in synthetic society. Notably, this reaction approach is scalable, transition-metal-free, and requires no external activator.
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Organic molecular catalysts have received great attention as they have the merits of well-controlled molecular structures for the development of catalytic chemistry. Herein, the electronic distribution of active sites is regulated by asymmetrically introducing S-heterocycle on one side of the molecular core. As a result, the asymmetric as-PYT and as-BNT show higher oxygen reduction performance than their symmetric counterparts without (s-PY, s-PY2T) or with two S-heterocycle units (s-BN, s-BN2T). Density functional theory calculations reveal that the carbon atoms (site-12) at symmetric s-BN and s-BN2T are the catalytic active sites, while for asymmetric as-BNT, it has changed to amino-N atom (site-14). Due to the non-uniform charge distribution and increased dipole moment of as-BNT caused by asymmetric molecular configuration, the kinetics of catalytic reaction has changed significantly. The catalytically active sites of specific N atoms are further verified experimentally and theoretically by using sterically hindered phenyl groups. This work provides a simple but efficient method to design metal-free oxygen reduction electrocatalysts.
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Metais , Oxigênio , Carbono , Catálise , Metais/química , Estrutura Molecular , Oxigênio/químicaRESUMO
Nonlinear Compton scattering is an inelastic scattering process where a photon is emitted due to the interaction between an electron and an intense laser field. With the development of X-ray free-electron lasers, the intensity of X-ray laser is greatly enhanced, and the signal from X-ray nonlinear Compton scattering is no longer weak. Although the nonlinear Compton scattering by an initially free electron has been thoroughly investigated, the mechanism of nonrelativistic nonlinear Compton scattering of X-ray photons by bound electrons is unclear yet. Here, we present a frequency-domain formulation based on the nonperturbative quantum electrodynamics to study nonlinear Compton scattering of two photons by an atom in a strong X-ray laser field. In contrast to previous theoretical works, our results clearly reveal the existence of a redshift phenomenon observed experimentally by Fuchs et al.(Nat. Phys.)11, 964(2015) and suggest its origin as the binding energy of the electron as well as the momentum transfer from incident photons to the electron during the scattering process. Our work builds a bridge between intense-laser atomic physics and Compton scattering processes that can be used to study atomic structure and dynamics at high laser intensities.
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BACKGROUND: The role of the sputum microbiome in chronic obstructive pulmonary disease (COPD) progression remains elusive. As the advent of the new culture-independent microbial sequencing technique makes it possible to disclose the complex microbiome community of the respiratory tract. The aim of this study was to use metagenomic next-generation sequencing (mNGS) to confirm whether there are differences in sputum microbiome of COPD between different exacerbation frequencies and lung function. METHODS: Thirty-nine COPD patients were divided into a frequent exacerbators (FE) group (n = 20) and a non-frequent exacerbators (NFE) (n = 19) group according to their exacerbation history, or a mild group (FEV1/pre ≥ 50%, n = 20) and a severe group (FEV1/pre < 50%, n = 19) according to the lung function. Sputum was collected during their stable phase, followed by DNA extraction, untargeted metagenomic next-generation sequencing (mNGS) and bioinformatic analysis. RESULTS: mNGS identified 3355 bacteria, 71 viruses and 22 fungi at the specie level. It was found that Shannon index and Simpson index in FE group was lower than that in NFE group (p = 0.005, 0.008, respectively) but similar between mild and severe groups. Out of top 10 bacteria taxa, Veillonella, Fusobacterium and Prevotella jejuni had a higher abundance in NFE group, Rothia had a higher abundance in mild group. Linear discriminant analysis revealed that many bacterial taxa were more abundant in NFE group, and they mostly belonged to Actinobacteria, Bacteroidetes and Fusobacteria phyla. Frequency of exacerbations was also found to be negatively correlated with alpha diversity (with Shannon index, r = - 0.423, p = 0.009; with Simpson index, r = - 0.482, p = 0.002). No significant correlation was observed between alpha diversity and FEV1/pre. CONCLUSIONS: Microbiome diversity in FE group was lower than that in NFE group. There was a significant difference in microbiome taxa abundance between FE and NFE groups, or mild and severe groups. These findings demonstrated that sputum microbiome community dysbiosis was associated with different exacerbation frequencies and lung function in stable COPD.
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Doença Pulmonar Obstrutiva Crônica , Escarro , Humanos , Escarro/microbiologia , Metagenoma/genética , Estudos de Casos e Controles , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Bactérias/genética , Pulmão/microbiologiaRESUMO
Particles can undergo different phase transitions in the atmosphere including deliquescence, liquid-liquid phase separation (LLPS), melting, and freezing. In this study, phase transitions of particles/droplets containing polyethylene glycol with a molar mass of 400 g mol-1 (PEG400) and ammonium sulfate (AS), i.e., PEG400-AS particles/droplets, were investigated at different organic-to-inorganic dry mass ratios (OIRs) under typical tropospheric temperatures and water activities (aw). The investigated droplets (60-100 µm) with or without LLPS in the closed system froze through homogeneous ice nucleation. At temperatures lower than 200 K, multiple ice nucleation events were observed within the same individual droplets at low aw. Droplets with and without LLPS shared similar lambda values at the same OIR according to the lambda approach indicating they form ice through the same mechanism. A parameterization of lambda values was provided which can be used to predict freezing temperature of aqueous PEG400-AS droplets. We found that adding AS reduces the temperature dependence of aw in aqueous PEG400 droplets. Assuming incorrectly that aw is temperature-independent for a constant droplet composition leads to a deviation between the experimental determined ice nucleation rate coefficients for droplets at OIR > 1 and the predicted values by the water-activity-based ice nucleation theory. We proposed a parameterization of temperature dependence of aw to minimize the deviations of the measured melting temperatures and nucleation rate coefficients from the corresponding predictions for aqueous PEG400-AS system.
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INTRODUCTION: Studies indicate a very low rate of SARS-CoV-2 detection in the placenta or occasionally a low rate of vertical transmission in COVID-19 pregnancy. SARS-CoV-2 Delta variant has become a dominant strain over the world and possesses higher infectivity due to mutations in its spike receptor-binding motif. CASE PRESENTATION: To determine whether SARS-CoV-2 Delta variant has increased potential for placenta infection and vertical transmission, we analyzed SARS-CoV-2 infection in the placenta, umbilical cord, and fetal membrane from a case where an unvaccinated mother and her neonate were COVID-19 positive. A 35-year-old primigravida with COVID-19 underwent an emergent cesarean delivery due to placental abruption in the setting of premature rupture of membranes. The neonate tested positive for SARS-CoV-2 within the first 24 h, and then again on days of life 2, 6, 13, and 21. The placenta exhibited intervillositis, increased fibrin deposition, and syncytiotrophoblast necrosis. Sequencing of viral RNA from fixed placental tissue revealed SAR-CoV-2 B.1.167.2 (Delta) variant. Both spike protein and viral RNA were abundantly present in syncytiotrophoblasts, cytotrophoblasts, umbilical cord vascular endothelium, and fetal membranes. CONCLUSION: We report with strong probability the first SARS-CoV-2 Delta variant transplacental transmission. Placental cells exhibited extensive apoptosis, senescence, and ferroptosis after SARS-CoV-2 Delta infection.
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COVID-19 , Complicações Infecciosas na Gravidez , Adulto , COVID-19/diagnóstico , Feminino , Humanos , Recém-Nascido , Placenta/irrigação sanguínea , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , RNA Viral , SARS-CoV-2RESUMO
To investigate the effects of the pixel sizes and the electrode structures on the performance of Ge-based terahertz (THz) photoconductive detectors, vertical structure Ge:Ga detectors with different structure parameters were fabricated. The characteristics of the detectors were investigated at 4.2 K, including the spectral response, blackbody response (Rbb), dark current density-voltage characters, and noise equivalent power (NEP). The detector with the pixel radius of 400 µm and the top electrode of the ring structure showed the best performance. The spectral response band of this detector was about 20-180 µm. The Rbb of this detector reached as high as 0.92 A/W, and the NEP reached 5.4 × 10-13 W/Hz at 0.5 V. Compared with the detector with a pixel radius of 1000 µm and the top electrode of the spot structure, the Rbb increased nearly six times, and the NEP decreased nearly 12 times. This is due to the fact that the optimized parameters increased the equivalent electric field of the detector. This work provides a route for future research into large-scale array Ge-based THz detectors.