The CoFeNC@NC Catalyst with Numerous Surface Cracks Bidirectionally Catalyzes the Conversion of Polysulfides to Accelerate the Reaction Kinetics of Lithium-Sulfur Batteries.

More and more attention has been paid to lithium-sulfur (Li─S) batteries due to their high energy density and low cost. However, the intractable "shuttle effect" and the low conductivity of S and its reaction product, Li2 S, compromise battery performance. To address the inherent challenges, a hollow composite catalyst as a separator coating material is designed, in which CoFe alloy is embedded in a carbon skeleton (CoFeNC@NC). In the hybrid structure, the carbon layer can endow the batteries with high electrical conductivity, while the CoFe alloy can effectively bidirectionally catalyze the conversion between lithium polysulfides (LiPSs) and Li2 S, accelerating the reaction kinetics and reducing the dissolution of LiPSs. Furthermore, the distinctive hollow structure with a cracked surface can facilitate the exposure of a more accessible catalytically active site and enhance Li+ diffusion. Benefiting from the synergistic effects, Li─S batteries with a CoFeNC@NC catalyst achieve a high sulfur utilization (1250.8 mAh g-1 at 0.2 C), superior rate performance (756 mAh g-1 at 2 C), and excellent cycling stability (an ultralow capacity fading of 0.054% per cycle at 1 C for 1000 cycles). Even at a sulfur loading of 5.3 mg cm-2 , a high area capacity of 4.05 mAh cm-2 can still be achieved after 100 cycles, demonstrating its potential practicality.

Characterization of antibody responses to SARS-CoV-2 in convalescent COVID-19 patients.

The coronavirus disease 2019 (COVID-19) is a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, little is known about the durability of the antibody response during COVID-19 convalescent phase. We investigated the prevalence of anti-SARS-CoV-2 specific antibodies including immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies and the dynamic changes in antibody levels in convalescent COVID-19 patients. A total of 159 blood samples were collected from 52 recovered COVID-19 patients up to six months after symptom onset for longitudinal serological tests. The positive rate of IgG and IgM antibodies was 92.3% and 90.4% in the first month after symptom onset, and the seropositivity of IgG antibody remained high at all follow-up time points, whereas the seropositivity of IgM antibody decreased to 22.73% by the sixth months after symptom onset. The level of IgG antibody was stable, the level of IgM antibody decreased slightly in the early convalescent phase and was detected in only five patients in the sixth month after symptom onset. The level of IgG antibody was higher in the severe and critical group than in the moderate group. The anti-SARS-CoV-2 specific antibodies have a long-term persistence in convalescent COVID-19 patients, whether they have long-term protection need to be further investigated.

Effect of artificial liver blood purification treatment on the survival of critical ill COVID-19 patients.

Our aim was to investigate the effect of artificial liver blood purification treatment on the survival of severe/critical patients with coronavirus disease 2019 (COVID-19). A total of 101 severe and critical patients with coronavirus SARS-CoV-2 infection were enrolled in this open, case-control, multicenter, prospective study. According to the patients' and their families' willingness, they were divided into two groups. One was named the treatment group, in which the patients received artificial liver therapy plus comprehensive treatment (n = 50), while the other was named the control group, in which the patients received only comprehensive treatment (n = 51). Clinical data and laboratory examinations, as well as the 28-day mortality rate, were collected and analyzed. Baseline data comparisons on average age, sex, pre-treatment morbidity, initial symptoms, vital signs, pneumonia severity index score, blood routine examination and biochemistry indices etc. showed no difference between the two groups. Cytokine storm was detected, with a significant increase of serum interleukin-6 (IL-6) level. The serum IL-6 level decreased from 119.94 to 20.49 pg/mL in the treatment group and increased from 40.42 to 50.81 pg/mL in the control group (P < .05), indicating that artificial liver therapy significantly decreased serum IL-6. The median duration of viral nucleic acid persistence was 19 days in the treatment group (ranging from 6 to 67 days) and 17 days in the control group (ranging from 3 to 68 days), no significant difference was observed (P = .36). As of 28-day follow-up,17 patients in the treatment group experienced a median weaning time of 24 days, while 11 patients in the control group experienced a median weaning time of 35 days, with no significant difference between the two groups (P = .33). The 28-day mortality rates were 16% (8/50) in the treatment group and 50.98% (26/51) in the control group, with a significant difference (z = 3.70, P < .001). Cytokine storm is a key factor in the intensification of COVID-19 pneumonia. The artificial liver therapy blocks the cytokine storm by clearing inflammatory mediators, thus preventing severe cases from progressing to critically ill stages and markedly reducing short-term mortality.

Develop an Adaptive Real-Time Indoor Intrusion Detection System Based on Empirical Analysis of OFDM Subcarriers.

Device-free passive intrusion detection is a promising technology to determine whether moving subjects are present without deploying any specific sensors or devices in the area of interest. With the rapid development of wireless technology, multi-input multi-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) which were originally exploited to improve the stability and bandwidth of Wi-Fi communication, can now support extensive applications such as indoor intrusion detection, patient monitoring, and healthcare monitoring for the elderly. At present, most research works use channel state information (CSI) in the IEEE 802.11n standard to analyze signals and select features. However, there are very limited studies on intrusion detection in real home environments that consider scenarios that include different motion speeds, different numbers of intruders, varying locations of devices, and whether people are present sleeping at home. In this paper, we propose an adaptive real-time indoor intrusion detection system using subcarrier correlation-based features based on the characteristics of narrow frequency spacing of adjacent subcarriers. We propose a link-pair selection algorithm for choosing an optimal link pair as a baseline for subsequent CSI processing. We prototype our system on commercial Wi-Fi devices and compare the overall performance with those of state-of-the-art approaches. The experimental results demonstrate that our system achieves impressive performance regardless of intruder's motion speeds, number of intruders, non-line-of-sight conditions, and sleeping occupant conditions.

Nuclear Radiation Degradation Study on HD Camera Based on CMOS Image Sensor at Different Dose Rates.

In this work, we irradiated a high-definition (HD) industrial camera based on a commercial-off-the-shelf (COTS) CMOS image sensor (CIS) with Cobalt-60 gamma-rays. All components of the camera under test were fabricated without radiation hardening, except for the lens. The irradiation experiments of the HD camera under biased conditions were carried out at 1.0, 10.0, 20.0, 50.0 and 100.0 Gy/h. During the experiment, we found that the tested camera showed a remarkable degradation after irradiation and differed in the dose rates. With the increase of dose rate, the same target images become brighter. Under the same dose rate, the radiation effect in bright area is lower than that in dark area. Under different dose rates, the higher the dose rate is, the worse the radiation effect will be in both bright and dark areas. And the standard deviations of bright and dark areas become greater. Furthermore, through the progressive degradation analysis of the captured image, experimental results demonstrate that the attenuation of signal to noise ratio (SNR) versus radiation time is not obvious at the same dose rate, and the degradation is more and more serious with increasing dose rate. Additionally, the decrease rate of SNR at 20.0, 50.0 and 100.0 Gy/h is far greater than that at 1.0 and 10.0 Gy/h. Even so, we confirm that the HD industrial camera is still working at 10.0 Gy/h during the 8 h of measurements, with a moderate decrease of the SNR (5 dB). The work is valuable and can provide suggestion for camera users in the radiation field.

Simultaneous mapping of reflectance, transmittance and optical loss of highly reflective and anti-reflective coatings with two-channel cavity ring-down technique.

We demonstrate the use of a two-channel cavity ring-down (CRD) technique for simultaneously measuring/mapping the reflectance R, transmittance T and optical loss L (absorption plus scattering losses) of highly reflective (HR) and anti-reflective (AR) laser components. High reflectance/transmittance of HR/AR components is measured with the ring-down time of CRD signals, while the low residual transmittance/ reflectance of HR/AR components is determined by the amplitude ratio of two CRD signals, and the optical loss is then determined via L = 1-R-T. Experiments are performed to measure and map R, T, and L of HR mirrors with different transmittance levels from below 1ppm to about 70 ppm (part-per-million) and of one AR window at 635nm. For a 4 ppm-transmittance HR mirror, the measured R, T, and L at one position are 99.99821 ± 0.00004%, 4.042 ± 0.008 ppm and 13.9 ± 0.4 ppm, respectively. For the AR sample, the measured T, R, and L at one position are 99.99279 ± 0.00004%, 50.0 ± 0.7 ppm and 22.0 ± 0.4 ppm, respectively. The sub-ppm standard deviations for R, T, and L indicate the high accuracy of the two-channel CRD technique for the simultaneous measurements of reflectivity, transmittance and optical loss of HR and AR components. High-resolution mappings of R, T, and L of both HR and AR samples are demonstrated. The simultaneous measurements/mappings of reflectance, transmittance, and optical loss with sub-ppm accuracy are of great importance to the preparation of high-performance laser optics for applications such as gravitational-wave detection and laser gyroscopes.

Extinction measurement with open-path cavity ring-down technique of variable cavity length.

Open-path cavity ring down (OPCRD) technique with variable cavity length was developed to measure optical extinction including scattering and absorption of air in laboratory environment at 635 nm wavelength. By moving the rear cavity mirror of the ring-down cavity to change cavity length, ring-down time with different cavity lengths was experimentally obtained and the dependence of total cavity loss on cavity length was determined. The extinction coefficient of air was determined by the slope of linear dependence of total cavity loss on cavity length. The extinction coefficients of air with different particle concentrations at 635 nm wavelength were measured to be from 10.46 to 84.19 Mm-1 (ppm/m) in a normal laboratory environment. This variable-cavity-length OPCRD technique can be used for absolute extinction measurement and real-time environmental monitoring without closed-path sample cells and background measurements.

Bioaugmentation of DDT-contaminated soil by dissemination of the catabolic plasmid pDOD.

A plasmid transfer-mediated bioaugmentation method for the enhancement of dichlorodiphenyltrichloroethane (DDT) degradation in soil was developed using the catabolic plasmid pDOD from Sphingobacterium sp. D-6. The pDOD plasmid could be transferred to soil bacteria, such as members of Cellulomonas, to form DDT degraders and thus accelerate DDT degradation. The transfer efficiency of pDOD was affected by the donor, temperature, moisture, and soil type. Approximately 50.7% of the DDT in the contaminated field was removed 210 days after the application of Escherichia coli TG I (pDOD-gfp). The results suggested that seeding pDOD into soil is an effective bioaugmentation method for enhancing the degradation of DDT.

Simultaneous determination of optical loss, residual reflectance and transmittance of highly anti-reflective coatings with cavity ring down technique.

Cavity ring down (CRD) technique was employed to measure optical losses (absorption and scattering losses), residual reflectance and transmittance of anti-reflectively (AR) coated laser components with transmittance higher than 99.9%. By inserting the AR coated laser component with parallel optical surfaces into the ring-down cavity and measuring the ring-down time versus the angle of incidence with respect to the surface normal, the optical loss and residual reflectance of the laser component were determined respectively at normal and out-of-normal incidences with repeatability of part-per-million level. The transmittance was also determined simultaneously. Experimental results demonstrated that CRD is a simple, inexpensive and fast technique for highly accurate measurements of optical loss, residual reflectance, and transmittance of AR coated laser components widely used in high-power laser systems.

Response of soil bacterial community to repeated applications of carbendazim.

The effect of repeated carbendazim applications on functional diversity of culturable microorganisms and bacterial community composition was studied under field conditions. The functional diversity of soil culturable microbial community (Shannon index, H') reduced significantly (P<0.05) after the first introduction of carbendazim at levels of 0.94, 1.88 and 4.70 kg active ingredient (a.i.)ha(-1) and then recovered to that in the control with subsequent applications. An evident (P<0.01) difference in the bacterial community composition was observed after the second carbendazim application by Temperature Gradient Gel Electrophoresis (TGGE) analysis of 16S rRNA genes amplified from treated and control soils, which remained after the third and fourth treatments. Our results indicated that repeated carbendazim applications have a transient harmful effect on functional diversity of soil culturable microbial community and result in an alteration in bacterial community composition largely due to one species within the γ-proteobacterium.

Isolation and characterization of Pseudomonas sp. CBW capable of degrading carbendazim.

With the intensive application of carbendazim in greenhouse production of vegetables and the production of medicinal herbs, there is an increasing need to find a way to remediate carbendazim-contaminated soil. A bacterial stain capable of utilizing carbendazim as the sole source of carbon and energy was isolated from soil. The isolate was designated CBW and identified as a member of Pseudomonas sp. based on its colony morphology, 16S rRNA gene sequencing and Biolog analysis. About 87.1 and 99.1% of carbendazim at concentrations of 1.0 and 10.0 mg l(-1) in mineral salts medium were removed by the isolate CBW after incubation for 3 days, respectively. The optimal pH value for the isolate CBW to degrade carbendazim was 7.0. The degradation rate of carbendazim by the isolate CBW was found to increase slightly with temperature. According to the metabolites detected and identified in the present study, it was proposed that carbendazim was first converted to 2-aminobenzimidazole, which was then transformed to 2-hydroxybenzimidazole, 1,2-diaminobenzene, catechol, and finally to carbon dioxide. The results indicate that the isolate CBW is a new bacterial resource for biodegrading carbendazim and might be used for bioremediation of sites heavily contaminated by carbendazim and its derivatives.

A novel exopolysaccharide-producing and long-chain n-alkane degrading bacterium Bacillus licheniformis strain DM-1 with potential application for in-situ enhanced oil recovery.

A novel Bacillus licheniformis strain (DM-1) was isolated from a mature reservoir in Dagang oilfield of China. DM-1 showed unique properties to utilize petroleum hydrocarbons and agroindustrial by-product (molasses) for exopolysaccharide (EPS) production under oil recovery conditions. The DM-1 EPS was proven to be a proteoglycan with a molecular weight of 568 kDa. The EPS showed shear thinning properties and had high viscosities at dilute concentrations (<1%, w/v), high salinities, and elevated temperatures. Strain DM-1 could degrade long-chain n-alkanes up to C36. Viscosity reduction test have shown that the viscosity of the crude oil was reduced by 40% compared with that before DM-1 treatment. Sand pack flooding test results under simulated reservoir conditions have shown that the enhanced oil recovery efficiency was 19.2% after 7 days of in-situ bioaugmentation with B. licheniformis DM-1. The obtained results indicate that strain DM-1 is a promising candidate for in situ microbial enhanced oil recovery (MEOR).

Carbendazim induces a temporary change in soil bacterial community structure.

The effect of carbendazim applications on the diversity and structure of a soil bacterial community was studied under field conditions using temperature gradient gel electrophoresis (TGGE) and partial sequence analysis of PCR-amplified 16S rRNA gene. After four successive introductions of carbendazim at a level of 0.94 kg active ingredient (a.i.)/ha, the genetic diversity (expressed as Shannon index, H') decreased from 1.43 in the control to 1.29 in treated soil. This harmful effect seems to increase with the concentration of carbendazim. The value of H' in the soil treated with carbendazim at 4.70 kg a.i./ha was reduced to 1.05 (P < or = 0.05). The structure of soil bacterial community was also affected after four repeated applications of carbendazim at levels of 0.94, 1.88 and 4.70 kg a.i./ha, as seen in the relative intensities of the individual band. However, the bacterial community in carbendazim-treated soil recovered to that in the control 360 d after the first treatment. The results indicated that repeated applications of carbendazim could reduce soil microbial diversity and alter the bacterial community structure temporarily.

Mini Review on Flexible and Wearable Electronics for Monitoring Human Health Information.

The application potential of wearable electronics in the healthcare field has been of great interest over the past several decades. Flexible and wearable devices based on skin-friendly soft elastic materials can be snugly attached to the surface of human skin, so that a series of vital health information such as wrist pulse, body temperature, and blood glucose can be extracted and analyzed to help the patient maintain physical fitness. Here, we outlined the most common types of wearable electronics for monitoring human health information, including force sensors, temperature sensors, physiological biochemical sensors, and multifunctional sensors. Their general working principles and structural innovations are reviewed. Then, we discussed two functional modules that make the wearable sensors more applicable in real life-self-powered module and signal processing module. The challenges and future research directions are also proposed to develop wearable electronics for monitoring human health information.

The Complete Chloroplast Genomes of Echinacanthus Species (Acanthaceae): Phylogenetic Relationships, Adaptive Evolution, and Screening of Molecular Markers.

Among the four species of Echinacanthus (Acanthaceae), one distributed in the West Himalayan region and three restricted to the Sino-Vietnamese karst region. Because of its ecological significance, molecular markers are necessary for proper assessment of its genetic diversity and phylogenetic relationships. Herein, the complete chloroplast genomes of four Echinacanthus species were determined for the first time. The results indicated that all the chloroplast genomes were mapped as a circular structure and each genomes included 113 unique genes, of which 80 were protein-coding, 29 were tRNAs, and 4 were rRNAs. However, the four cp genomes ranged from 151,333 to 152,672 bp in length. Comparison of the four cp genomes showed that the divergence level was greater between geographic groups. We also analyzed IR expansion or contraction in the four cp genomes and the fifth type of the large single copy/inverted repeat region in Lamiales was suggested. Furthermore, based on the analyses of comparison and nucleotide variability, six most divergent sequences (rrn16, ycf1, ndhA, rps16-trnQ-UUG, trnS-GCU-trnG-UCC, and psaA-ycf3) were identified. A total of 37-45 simple sequence repeats were discovered in the four species and 22 SSRs were identified as candidate effective molecular markers for detecting interspecies polymorphisms. These SSRs and hotspot regions could be used as potential molecular markers for future study. Phylogenetic analysis based on Bayesian and parsimony methods did not support the monophyly of Echinacanthus. The phylogenetic relationships among the four species were clearly resolved and the results supported the recognition of the Sino-Vietnamese Echinacanthus species as a new genus. Based on the protein sequence evolution analysis, 12 genes (rpl14, rpl16, rps4, rps15, rps18, rps19, psbK, psbN, ndhC, ndhJ, rpoB, and infA) were detected under positive selection in branch of Sino-Vietnamese Echinacanthus species. These genes will lead to understanding the adaptation of Echinacanthus species to karst environment. The study will help to resolve the phylogenetic relationship and understand the adaptive evolution of Echinacanthus. It will also provide genomic resources and potential markers suitable for future species identification and speciation studies of the genus.

An efficient model for auxiliary diagnosis of hepatocellular carcinoma based on gene expression programming.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide. The early diagnosis of HCC is greatly helpful to achieve long-term disease-free survival. However, HCC is usually difficult to be diagnosed at an early stage. The aim of this study was to create the prediction model to diagnose HCC based on gene expression programming (GEP). GEP is an evolutionary algorithm and a domain-independent problem-solving technique. Clinical data show that six serum biomarkers, including gamma-glutamyl transferase, C-reaction protein, carcinoembryonic antigen, alpha-fetoprotein, carbohydrate antigen 153, and carbohydrate antigen 199, are related to HCC characteristics. In this study, the prediction of HCC was made based on these six biomarkers (195 HCC patients and 215 non-HCC controls) by setting up optimal joint models with GEP. The GEP model discriminated 353 out of 410 subjects, representing a determination coefficient of 86.28% (283/328) and 85.37% (70/82) for training and test sets, respectively. Compared to the results from the support vector machine, the artificial neural network, and the multilayer perceptron, GEP showed a better outcome. The results suggested that GEP modeling was a promising and excellent tool in diagnosis of hepatocellular carcinoma, and it could be widely used in HCC auxiliary diagnosis. Graphical abstract The process to establish an efficient model for auxiliary diagnosis of hepatocellular carcinoma.

Association between STAT4 polymorphisms and risk of primary biliary cholangitis: a meta-analysis.

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease. Several studies reported that SATA4 (signal transducer and activator of transcription 4) polymorphisms were significantly associated with PBC susceptibility. In order to derive a more comprehensive estimation of the association between STAT4 and PBC risk, this meta-analysis was conducted. Thirteen eligible studies from 8 articles with a total number of 11,310 cases and 27,844 controls were included in this meta-analysis. Pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated with fixed effects model or random effects model. The results showed statistically significant association between polymorphisms of rs7574865, rs3024921, rs6752770, rs7601754 and rs10168266 in STAT4 and PBC risk under the allelic effect model (rs7574865, T vs. G, OR = 1.24, 95% CI 1.14-1.35; rs3024921, T vs. A, OR = 1.65, 95% CI 1.44-1.91; rs6752770, G vs. A, OR = 1.24, 95% CI 1.11-1.39; rs7601754, A vs. G, OR = 1.35, 95% CI 1.17-1.55; and rs10168266, T vs. C, OR = 1.31, 95% CI 1.22-1.41). Furthermore, the rs7574865 polymorphism was significantly associated with PBC risk under all genotype genetic models (dominant effect model: TT + TG vs. GG, OR = 1.43, 95% CI 1.19-1.71; recessive effect: TT vs. TG + GG, OR = 1.40, 95% CI 1.24-1.58; and co-dominant effect: TT vs. GG, OR = 1.67, 95% CI 1.37-2.02). The sensitivity analysis by omitting one study at a time showed that the results were stable. No publication bias was indicated from both Begg's test and Egger's weighted regression. This meta-analysis suggested that polymorphisms of rs7574865, rs3024921, rs6752770, rs7601754 and rs10168266 in STAT4 were significantly associated with the risk of PBC.

The complete genome of Ziziphus jujuba cv. dongzao, an economic crop in Yellow River Delta of China.

The complete chloroplast genome of Ziziphus jujuba cv. dongzao, known as an important economic cultivar in Yellow River Delta of China was reported. It exhibits a quadripartite structure with 161,493 bp including a large single copy region (89,178 bp), a small single copy region (19,357 bp) and a pair of inverted repeats regions (26,479 bp). It has 36.79% GC content and 114 unique genes. Phylogenetic analysis showed that it was a member of Ziziphus and more closely related to Berchemiella wilsonii. Border analysis revealed that there were some differences in the borders of the four related cultivars.

Dual-wavelength retinal images denoising algorithm for improving the accuracy of oxygen saturation calculation.

Noninvasive measurement of hemoglobin oxygen saturation ( SO 2 ) in retinal vessels is based on spectrophotometry and spectral absorption characteristics of tissue. Retinal images at 570 and 600 nm are simultaneously captured by dual-wavelength retinal oximetry based on fundus camera. SO 2 is finally measured after vessel segmentation, image registration, and calculation of optical density ratio of two images. However, image noise can dramatically affect subsequent image processing and SO 2 calculation accuracy. The aforementioned problem remains to be addressed. The purpose of this study was to improve image quality and SO 2 calculation accuracy by noise analysis and denoising algorithm for dual-wavelength images. First, noise parameters were estimated by mixed Poisson­Gaussian (MPG) noise model. Second, an MPG denoising algorithm which we called variance stabilizing transform (VST) + dual-domain image denoising (DDID) was proposed based on VST and improved dual-domain filter. The results show that VST + DDID is able to effectively remove MPG noise and preserve image edge details. VST + DDID is better than VST + block-matching and three-dimensional filtering, especially in preserving low-contrast details. The following simulation and analysis indicate that MPG noise in the retinal images can lead to erroneously low measurement for SO 2 , and the denoised images can provide more accurate grayscale values for retinal oximetry.

Wuacanthus (Acanthaceae), a new Chinese endemic genus segregated from Justicia (Acanthaceae).

A new genus, Wuacanthus Y.F. Deng, N.H. Xia & H. Peng (Acanthaceae), is described from the Hengduan Mountains, China. Wuacanthus is based on Wuacanthus microdontus (W.W.Sm.) Y.F. Deng, N.H. Xia & H. Peng, originally published in Justicia and then moved to Mananthes. The new genus is characterized by its shrub habit, strongly 2-lipped corolla, the 2-lobed upper lip, 3-lobed lower lip, 2 stamens, bithecous anthers, parallel thecae with two spurs at the base, 2 ovules in each locule, and the 4-seeded capsule. Phylogenetic analyses show that the new genus belongs to the Pseuderanthemum lineage in tribe Justicieae. Wuacanthus is closely related to Pseuderanthemum but differs from the latter by its shorter corolla tube and two minute spurs at the base of each anther-theca. W. microdontus is assessed with the status EN B2ab (iii) based on the IUCN Red List Categories and Criteria.