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More than 80% of coronavirus disease 2019 (COVID-19) cases are mild or moderate. In this study, a risk model was developed for predicting rehabilitation duration (the time from hospital admission to discharge) of the mild-moderate COVID-19 cases and was used to conduct refined risk management for different risk populations.
A total of 90 consecutive patients with mild-moderate COVID-19 were enrolled. Large-scale datasets were extracted from clinical practices. Through the multivariable linear regression analysis, the model was based on significant risk factors and was developed for predicting the rehabilitation duration of mild-moderate cases of COVID-19. To assess the local epidemic situation, risk management was conducted by weighing the risk of populations at different risk.
Ten risk factors from 44 high-dimensional clinical datasets were significantly correlated to rehabilitation duration (P < 0.05). Among these factors, 5 risk predictors were incorporated into a risk model. Individual rehabilitation durations were effectively calculated. Weighing the local epidemic situation, threshold probability was classified for low risk, intermediate risk, and high risk. Using this classification, risk management was based on a treatment flowchart tailored for clinical decision-making.
The proposed novel model is a useful tool for individualized risk management of mild-moderate COVID-19 cases, and it may readily facilitate dynamic clinical decision-making for different risk populations.
Human African trypanosomiasis (HAT) is caused by Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense and caused devastating epidemics during the 20th century. Due to effective control programs implemented in the last two decades, the number of reported cases has fallen to a historically low level. Although fewer than 977 cases were reported in 2018 in endemic countries, HAT is still a public health problem in endemic regions until it is completely eliminated. In addition, almost 150 confirmed HAT cases were reported in non-endemic countries in the last three decades. The majority of non-endemic HAT cases were reported in Europe, USA and South Africa, due to historical alliances, economic links or geographic proximity to disease-endemic countries. Furthermore, with the implementation of the ‘Belt and Road’ project, sporadic imported HAT cases have been reported in China as a warning sign of tropical diseases prevention. In this paper, we explore and interpret the data on HAT incidence and find no positive correlation between the number of HAT cases from endemic and non-endemic countries. This data will provide useful information for better understanding the imported cases of HAT globally in the post-elimination phase.
Previously the GABA(A) receptor beta-2 subunit gene GABRB2 was found to be associated with schizophrenia (SCZ). for SNPs and haplotypes in GRBRB2, the associations with bipolar disorder (BPD), the functional consequences on GABRB2 expression and their relationship to demographic and clinical characteristics in BPD and SCZ remain to be elucidated.
Case-control analysis was performed for association study of GABRB2 with BPD, and its mRNA expression in postmortem BPD brains was examined using quantitative real-time PCR. Quantitative trait analysis was subsequently employed to assess the covariate effects of demographic and clinical characteristics on genotypic correlation of GABRB2 expression in SCZ and BPD.
Significant association of GABRB2 with BPD and reduction in GABRB2 mRNA expression in BPD brains were observed in the present study. Duration of illness (DOI) was found to be a significant covariate for the correlation of the disease-associated SNPs rs1816071, rs1816072 and rs187269 with GABRB2 expression in both SCZ and BPD. for individuals with homozygous major genotypes of these SNPs, while GABRB2 expression increased with age in the controls, it decreased with DOI and age in SCZ, and with DOI in BPD. with age of onset as covariate, these three SNPs were significantly correlated with antipsychotic dosage in SCZ.
These results have thus revealed correlations of GABRB2 SNPs and expression not only with the occurrence of SCZ and BPD, but also with the clinical characteristics of patients, therefore providing support for a shared etiological role played by the gene in both diseases.
Four putative knockdown resistance (kdr) mutations have been documented in the voltage-gated sodium channel (VGSC) gene of Cimex hemipterus from several countries. However, no information regarding kdr mutations in any Chinese tropical bed bug population is available to date. In this study, a double-mutation（M918I + L1014F）kdr allele was identified in six C. hemipterus populations across Guangxi Zhuang Autonomous Region of China. The frequency of this allele was 100% in all the six examined populations. In addition, only two cytochrome c oxidase I (COI) gene haplotypes, with one synonymous nucleotide variation, were identified in a total of 48 individuals from six locations. The fixation and broad geographic distribution of this resistant allele questions the continued use of pyrethroids in the treatment of tropical bed bug infestations. The very low genetic diversity within and among these populations indicates that these bed bugs may have a single origin.
Emerging transient electronics capable of complete physical and chemical disintegration are derived from advanced materials and device design strategies. The area of exploring on-demand smart transient electronics has seen continuous development, allowing for the degradation process to be triggered or controlled through an instantaneous stimulus, thus offering significant potential in data security, undetectable spying, and bioresorbable electronics applications. In this article, we summarize recent progress in the design and strategies of on-demand smart transient electronics and emphasize the basic principles of selecting, processing, and integrating materials. After an introduction to the history and properties of triggered transient electronics, we discuss on-demand smart transient electronics based on their triggering stimuli, strategies for designing thermal, optical, or electrical triggers, and future development trends and challenges.
This paper presents a comprehensive study of the zircon geochronology, geochemistry and Sr–Nd isotope geology of Devonian mafic rocks developed in the East Kunlun orogenic belt, northern Tibetan Plateau, and reveals their mantle sources, petrogenesis and geodynamic implications for continental exhumation. The zircon geochronology of typical samples indicates that these mafic rocks crystallized at 406∼408 Ma. They can be classified into two different groups based on petrographic observations and geochemical compositions. Group 1 rocks exhibit low TiO2 and FeOt contents and Nb/Y ratios and have enriched mid-ocean ridge basalt (E-MORB)-like compositions with slight negative Nb and Ta anomalies. However, Group 2 rocks have distinctly high TiO2 and FeOt contents and Nb/Y ratios, comparable to typical Fe–Ti-rich mafic rocks worldwide. All the samples exhibit weak enrichments in light rare earth elements, Nb and Ta relative to the primitive mantle. Based on geochemical and isotopic studies, Group 1 rocks are suggested to be derived from depleted asthenospheric mantle that was metasomatized by c. 3–5 % continental crustal components, while Group 2 rocks originated from partial melting of enriched lithospheric mantle. The high contents of Fe, Ti and Nb for Group 2 rocks could be attributed to a high degree of olivine crystallization under low fO2 conditions with delayed nucleation of Fe–Ti oxides. Combining those results with other geological data, we conclude that slab break-off was the key factor causing exhumation of eclogites and triggering flare-up of the Devonian magmatism, and that continental collision or continental subduction may have initiated at 431∼436 Ma.
There is increasing evidence that both black and green tea are beneficial for prevention of cardiovascular disease (CVD). We conducted a systematic review and meta-analysis evaluating the effects of tea flavonoids on cardiovascular (CVD) and all-cause mortality outcomes.Searches across five databases including PubMed and Embase were conducted through November 2018 to identify randomized controlled trials (RCTs) and prospective cohort studies reporting cardiovascular and all-cause mortality outcomes. Two investigators independently conducted abstract and full-text screenings, data extractions, and risk of bias (ROB) assessments using the Nutrition Evidence Library Bias Assessment Tool (NEL BAT). Mixed-effects dose-response meta-regression and standard random-effects meta-analyses for outcomes with ≥ 4 studies were performed. 0 RCTs and 38 prospective cohort studies were included in the systematic review. NEL BAT scores ranged from 0–15 (0 being the lowest risk). Our linear meta-regression model showed that each cup increase in daily tea consumption (about 280 mg and 338 mg of total flavonoids for black and green tea, respectively) was associated with 3–4% lower risk of CVD mortality (predicted adjusted RR = 0.96; CI 0.93–0.99 for green tea and RR = 0.97; CI 0.94–0.99 for black tea). Furthermore, eachcup increase in daily tea consumption was associated a 2% lower risk of all-cause mortality (predicted adjusted relative risk (RR) = 0.98; 95% CI 0.97–0.99 for black tea and RR = 0.98; CI 0.96–0.99 for green tea, respectively). Two studies reported multivariable Cox regression analysis results for the relationship between black tea intake and risks of all-cause mortality outcomes. The results from these two studies were combined with our linear meta-regression result in a random-effects model meta-analysis and showed that each cup increase in daily black tea consumption was associated with an average of 3% lower risk of all-cause mortality (pooled adjusted RR = 0.97; 95% CI 0.87- 1.00) with large heterogeneity (I2 = 81.4%; p = 0.005). Current evidence indicates that increased tea consumption may reduce cardiovascular and all-cause mortality in a dose-response manner. This systematic review was registered on PROSPERO.
Nanostructures are considered to have great potential and are widely used in energy storage and sensing devices, and atomic layer deposition (ALD) is of great help for better nanostructure fabrications. ALD can help to preserve the original properties of materials, and, meanwhile, the excellent film quality, nanoscale precise thickness control, and high conformality also play important role in fabrication process. To enhance the performance of energy storage and sensor devices, ALD has been used in directly fabricating active nanostructures, depositing protective passivation layers, etc. ALD is a convenient technique which has been widely engaged in energy-related fields including electrochemical conversion and storage, as well as in sensor and biosensors. The related research interest is increasing significantly. In this review, we summarize some of the latest works on ALD for batteries, supercapacitors, and sensors, and demonstrate the benefits of ALD comprehensively. In these devices, different materials are deposited by ALD under different conditions to achieve better battery performance, higher supercapacitor capacitance, and higher sensitivity. This review fully presents the strengths of ALD and its application in energy storage and sensing devices and proposes the future prospects for this rapidly developing technology.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
A comprehensive geochronological and geochemical study was carried out on the gneissic monzogranites, porphyritic granodiorites and charnockites in the Gaozhou complex of the Yunkai massif in the southern part of the South China block to better understand the Early Palaeozoic tectonic regime of the South China block. Laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) U–Pb dating of zircons indicates an age of 453.2 ± 5.1 Ma to the formation of the gneissic monzogranites, whereas the porphyritic granodiorites and charnockites were generated at 437.0 ± 1.5 Ma and 435.2 ± 2.2 Ma, respectively. The gneissic monzogranites show geochemical features consistent with the high-K, calc-alkaline rock series and are strongly peraluminous. They have SiO2 contents ranging from 67.75 to 69.65 wt. % and relatively low CaO contents (1.66–1.94 wt. %). Their REE patterns are fractionated with enriched LREEs and negative Eu anomalies. The samples also show enrichment in LILEs (e.g. Rb and K) and Pb, and depletion in Sr, Ba and HFSEs (e.g. Nb, Ta, Ti and P). They have εNd(t) values of −8.2 to −7.7. Conversely, the porphyritic granodiorites and charnockites are characterized as medium-K, calc-alkaline rock series and weakly to strongly peraluminous. They exhibit pronounced depletions in HFSEs and positive Pb anomalies. Compared to the earlier gneissic monzogranites, these rocks have relatively lower SiO2 (65.50–69.36 wt. %), but higher CaO contents (3.34–4.05 wt. %), and have slightly lower εNd(t) values (−9.1 to −8.4). Petrography and geochemical compositions of the gneissic monzogranites indicate that they are S-type granite and likely formed by partial melting of Neoproterozoic to Early Palaeozoic immature metagreywackes; whereas The porphyritic granodiorites and charnockites are A-type granite and likely derived from low degrees of partial melting of the dry, granulitic residue depleted by prior extraction of granitic melt. The new data for the Caledonian granitoids in the Yunkai massif suggest that they were formed in a post-collisional tectonic setting. They represent the earliest post-collisional alkaline magmatism reported so far in the Yunkai massif, and thus indicate a tectonic regime switch, from compression to extension, as early as the Late Ordovician to Early Silurian (~450–435 Ma).
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
Palaeoproterozic metasedimentary rocks, also referred to as khondalites, characterized by Al-rich minerals, are extensively exposed in the nucleus of the Yangtze craton, South China block. Samples of garnet–sillimanite gneiss in the khondalite suite were collected from the Kongling complex for Nd isotopic and elemental geochemical study. These rocks are characterized by variable SiO2 contents ranging from 35.71 to 58.07 wt%, and have low CaO (0.45–0.84 wt%) but high Al2O3 (18.56–29.04 wt%), Cr (174–334 ppm) and Ni (42.5–153 ppm) contents. They have high CIW (Chemical Index of Weathering) values (90.4–94.7), indicating intense chemical weathering of the source material. The samples display light rare earth elements (LREE) enrichment with negative Eu anomalies (Eu/Eu*=0.40–0.68), and have flat heavy rare earth elements (HREE) patterns. The high contents of transition elements (e.g. Cr, Ni, Sc, V) and moderately radiogenic Nd isotopic compositions suggest that the paragneisses might be those of first-cycle erosion products of predominantly mafic rocks mixing with small amounts of felsic moderately evolved Archaean crustal source. Geochemical and Nd isotopic compositions reveal that at least some of the protoliths of Kongling khondalite were sourced from local pre-existing mafic igneous rocks in a continental arc tectonic setting. Combined with documented zircon U–Pb geochronological data, we propose that the Palaeoproterozoic high-pressure granulite-facies metamorphism, rapid weathering, erosion and deposition of the khondalites in the interior of the Yangtze craton might be related to a Palaeoproterozoic collisional orogenic event during 2.1–1.9 Ga, consistent with the worldwide contemporary orogeny, implying that the Yangtze craton may have been an important component of the Palaeoprotorozoic Columbia supercontinent.
A series of novel KLaSr3−x(PO4)3F:xEu2+ phosphors were synthesized for the first time. The crystal structure, photoluminescence properties, concentration quenching, decay analysis, and the temperature dependent luminescence properties were investigated in detail. The unit cell parameters for KLaSr3(PO4)3F were estimated to be a = 9.8997 Å, c = 7.4075 Å, and V = 628.7 Å3. The photoluminescence excitation spectrum of KLaSr3(PO4)3F:Eu2+ shows a broad band from 225 nm to 450 nm with a maximum at about 320 nm. KLaSr3−x(PO4)3F:xEu2+ phosphors exhibit a wide emission band ranging from 425 to 550 nm. KLaSr3(PO4)3F:Eu2+ phosphors exhibit good thermal stability up to 423 K. KLaSr3(PO4)3F:Eu2+ was fabricated with commercial green (Ba,Sr)SiO4:Eu2+ and red CaAlSiN3:Eu2+ phosphors to obtain a white-light-emitting diode. All the results demonstrate that KLaSr3(PO4)3F:Eu2+ are promising blue phosphors for white-light ultraviolet light-emitting diode applications.
A facile method that allows chemical functionalization of graphene sheets is described. These result in a solution processable graphene-based material, namely F-graphene, which can be integrated in organic photoelectronic devices, due to its unique structural and photophysical properties. The resultant poly(3-hexylthiophene)(P3HT):F-graphene are soluble in common organic solvents, facilitating the structure/property characterization and the device fabrication by solution processing. The synthesized F-graphene is blended with the conjugated polymer in optimized concentration. The high and sensitive photoresponse of P3HT:F-graphene was demonstrated by the photodetector. A heterojunction photovoltaic device based on the solution-cast P3HT:F-graphene (with a BHJ structure of ITO/ZnO/P3HT:F-graphene/MoO3/Ag) showed a power conversion efficiency of 1.9% under AM1.5 illumination (100 mW/cm2). It provides a new method for graphene application in organic photoelectronics. It can easily enhance the performance of devices by optimizing the structure and bulk heterojunction blend in the near future.
Traditional studies of early bronze metallurgy in China have focused on typology, decoration and production methods. The application of new analytical techniques to investigate chemical composition, however, is offering important new insights. The use of one such method (electron probe microanalysis) to study bronze artefacts from the Hanzhong basin in central China shows a level of diversity that implies much greater complexity in the extended landscape networks of the Bronze Age than was previously thought. The ability to appreciate these finds from a new perspective allows progression beyond older, simplistic models, and demonstrates that the Hanzhong region held greater importance within the power structure of Bronze Age Central China than has previously been recognised.
Novel plate-stratiform nanostructured Bi12O17Cl2 was studied with its visible-light photocatalytic performance. The Bi12O17Cl2 photocatalyst synthesized by a solid-state reaction was constructed of dozens of primary nanosheets, which were stacked by a parallel array of ultrathin secondary nanosheets. The microstructure and crystal structure of Bi12O17Cl2 primary and secondary nanosheets were discovered by high-resolution transmission electron microscopy and selected-area electron diffraction analyses. Its absorption edge was determined as about 590 nm and the band gap energy was 2.1 eV. The Bi12O17Cl2 nanomaterial exhibited superior visible-light-responsive photocatalytic activity and confirmed successful photodegradation of methyl orange (MO) under visible-light irradiation. The degradation efficiency was up to 97% in 90 min. Furthermore, the Bi12O17Cl2 photocatalyst exhibited excellent photostability and high mineralization capacity for MO photodegradation reaction. The MO photodegradation process was dominated by the direct photocatalytic mechanism. The contribution from its morphology and microstructure to superior photocatalytic activity was discussed.
The prevalence and factors associated with delays in help seeking for people with dementia in China are unknown.
Within 1,010 consecutively registered participants in the Clinical Pathway for Alzheimer's Disease in China (CPAD) study (NCT01779310), 576 persons with dementia (PWDs) and their informants reported the estimated time from symptom onset to first medical visit seeking diagnosis. Univariate analysis of general linear model was used to examine the potential factors associated with the delayed diagnosis seeking.
The median duration from the first noticeable symptom to the first visit seeking diagnosis or treatment was 1.77 years. Individuals with a positive family history of dementia had longer duration (p = 0.05). Compared with other types of dementia, people with vascular dementia (VaD) were referred for diagnosis earliest, and the sequence for such delays was: VaD < Alzheimer's disease (AD) < frontotemporal dementia (FTD) (p < 0.001). Subtypes of dementia (p < 0.001), family history (p = 0.01), and education level (p = 0.03) were associated with the increased delay in help seeking.
In China, seeking diagnosis for PWDs is delayed for approximately 2 years, even in well-established memory clinics. Clinical features, family history, and less education may impede help seeking in dementia care.
The present study investigated the effects of social defeat stress on the behaviours and expressions of 78-kDa glucose-regulated protein (Grp78), CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) and choline acetyltransferase (Chat) in the brains of adolescent mice. Adolescent male C57BL/6J mice were divided into two groups (susceptible and unsusceptible) after 10 d social defeat stress. In expt 1, behavioural tests were conducted and brains were processed for Western blotting on day 21 after stress. In expt 2, social avoidance tests were conducted and brains were subsequently processed for Western blotting on day 12 after stress. Chronic social defeat stress produced more pronounced depression-like behaviours such as decreased locomotion and social interaction, increased anxiety-like behaviours and immobility, and impaired memory performance in susceptible mice. Moreover, susceptible mice showed greater expression of Grp78 and CHOP in the amygdala (Amyg) on days 12 and 21 compared with the other groups. Susceptible and unsusceptible groups showed significant increases in Grp78 and CHOP expression in the prefrontal cortex (PFC) and hippocampus (Hipp) on day 12 compared with the control group; this persisted until day 21. The levels of Chat measured on days 12 and 21 were significantly lower in the PFC, Amyg and Hipp of all defeated mice compared with controls. The findings of the behavioural tests indicate that chronic social defeat in adolescents produces anxiety-like behaviours, social withdrawal, despair-like behaviours and cognitive impairment. The Grp78, CHOP and Chat results suggest that the selective response of endoplasmic reticulum stress proteins in the Amyg plays an important role in the vulnerability–stress model of depression.