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The high concentration of fine particles and gaseous pollutants makes polluted areas, such as the urban setting of North China Plain (NCP) of China, a different environment for new particle formation (NPF) compared to many clean regions. Such conditions also hold for other polluted environments in this region (for instance, the rural area of NCP), yet the underlying mechanisms for NPF remain less understood, owing to the limited observations of particles in the sub−3 nm range. Comprehensive measurements, particularly covering the particle number size distribution down to 1.3 nm, were conducted at a rural background site of Gucheng (GC) in the North China Plain (NCP) from 12 November to 24 December 2018. In total, five NPF events during the 39 effective days of measurements for the campaign were identified, with the mean particle nucleation rate (J1.3) and growth rate (GR1.3–2.4) being 22.0 cm−3 s−1 and 3.9 nm h−1, respectively. During these 5 d, NPF concurrently occurred at an urban site in Beijing. Sharing similar sources and transport paths of air masses arriving at our site to that of urban Beijing, we hypothesize that NPF events during these days in this region might be a regional phenomenon. The simultaneous occurrence of NPF in both places implies that H2SO4-amine nucleation, concluded for urban Beijing there, could probably be the dominating mechanism for NPF at our rural site. The higher concentration of sulfuric acid during many non-event days compared to that of event days indicates that the content of sulfuric acid may not necessarily lead to NPF events under current atmosphere. Only when the condensation sink or coagulation sink was significantly lowered, atmospheric NPF occurred, implying that condensation sinks (CSs) and coagulation sinks (CoagSs) are the dominating factors controlling the occurrence of NPF for the present rural environment of the NCP, which is quite similar to the feature seen in urban Beijing.

The high concentration of fine particles as well as gaseous pollutants makes polluted areas, such as the urban setting of North China Plain (NCP) of China, a different environment for NPF compared to many clean regions. Such conditions also hold for other polluted environments in this region, for instance, the rural area of NCP, yet the underlying mechanisms for NPF remain less understood owing to the limited observations of particles in the sub-3nm range. Comprehensive measurements, particularly covering the particle number size distribution down to 1.34 nm, were conducted at a rural background site of Gucheng (GC) in the North China Plain (NCP) from 12 November to 24 December in 2018. Five NPF events during the 39 effective days of measurements for the campaign were identified, with the mean particle nucleation rate (J1.34) and growth rate (GR1.34-2.4) were 29.1 cm-3·s-1 and 0.54 nm·h-1, respectively. During these five days, NPF concurrently occurred in an urban site in Beijing, indicating that NPF events during these days in this region might be a regional phenomena. This implies that H2SO4-amine nucleation, concluded for urban Beijing there, could also be the dominating mechanism for NPF at our rural site. The condensation sink or coagulation sink for the survival of newly-formed and small clusters are the dominating factor controlling the occurrence of NPF under current atmosphere, whereas the contribution from the available H2SO4 cannot be neglected, either. This feature is slightly different from that of urban Beijing, where CS mainly determines whether NPF takes place or not.

Brown carbon (BrC) has been recognized as an important contributor to global warming due to its absorption of solar radiation with strong wavelength dependence. While early studies mostly consider biomass burning as a major emission source, a few recent studies have suggested coal combustion and vehicle exhaust as important contributors to BrC emissions. Considering dominant coal consumption, large residential biofuel usage, and the increasing number of vehicles, BrC pollution could result in remarkable regional climate effects in China. This study gives an overview of sources, chemical composition and absorption properties of BrC, focusing on BrC categorization and its absorption measurement techniques. The basic pollution features of BrC in China, including surface concentrations, column burden, sources and associated absorbing properties are then summarized and compared to other countries. BrC emissions as well as its optical emission at 365 nm from the primary sources in China are also summarized to provide a more straightforward understanding of the light-absorbing properties of BrC in China. With a detailed comparison of existing publications, the study gives deeper insight into the uncertainties in BrC measurements and will improve the understanding of the climate effect of BrC. The review also recommends key research areas for further investigation of BrC in the future.

We present the results for CAPRI Round 50, the fourth joint CASP-CAPRI protein assembly prediction challenge. The Round comprised a total of twelve targets, including six dimers, three trimers, and three higher-order oligomers. Four of these were easy targets, for which good structural templates were available either for the full assembly, or for the main interfaces (of the higher-order oligomers). Eight were difficult targets for which only distantly related templates were found for the individual subunits. Twenty-five CAPRI groups including eight automatic servers submitted ~1250 models per target. Twenty groups including six servers participated in the CAPRI scoring challenge submitted ~190 models per target. The accuracy of the predicted models was evaluated using the classical CAPRI criteria. The prediction performance was measured by a weighted scoring scheme that takes into account the number of models of acceptable quality or higher submitted by each group as part of their five top-ranking models. Compared to the previous CASP-CAPRI challenge, top performing groups submitted such models for a larger fraction (70–75%) of the targets in this Round, but fewer of these models were of high accuracy. Scorer groups achieved stronger performance with more groups submitting correct models for 70–80% of the targets or achieving high accuracy predictions. Servers performed less well in general, except for the MDOCKPP and LZERD servers, who performed on par with human groups. In addition to these results, major advances in methodology are discussed, providing an informative overview of where the prediction of protein assemblies currently stands., Cancer Research UK, Grant/Award Number: FC001003; Changzhou Science and Technology Bureau, Grant/Award Number: CE20200503; Department of Energy and Climate Change, Grant/Award Numbers: DE-AR001213, DE-SC0020400, DE-SC0021303; H2020 European Institute of Innovation and Technology, Grant/Award Numbers: 675728, 777536, 823830; Institut national de recherche en informatique et en automatique (INRIA), Grant/Award Number: Cordi-S; Lietuvos Mokslo Taryba, Grant/Award Numbers: S-MIP-17-60, S-MIP-21-35; Medical Research Council, Grant/Award Number: FC001003; Japan Society for the Promotion of Science KAKENHI, Grant/Award Number: JP19J00950; Ministerio de Ciencia e Innovación, Grant/Award Number: PID2019-110167RB-I00; Narodowe Centrum Nauki, Grant/Award Numbers: UMO-2017/25/B/ST4/01026, UMO-2017/26/M/ST4/00044, UMO-2017/27/B/ST4/00926; National Institute of General Medical Sciences, Grant/Award Numbers: R21GM127952, R35GM118078, RM1135136, T32GM132024; National Institutes of Health, Grant/Award Numbers: R01GM074255, R01GM078221, R01GM093123, R01GM109980, R01GM133840, R01GN123055, R01HL142301, R35GM124952, R35GM136409; National Natural Science Foundation of China, Grant/Award Number: 81603152; National Science Foundation, Grant/Award Numbers: AF1645512, CCF1943008, CMMI1825941, DBI1759277, DBI1759934, DBI1917263, DBI20036350, IIS1763246, MCB1925643; NWO, Grant/Award Number: TOP-PUNT 718.015.001; Wellcome Trust, Grant/Award Number: FC001003

Fe and Co doped Mn-Ce/TiO2 catalysts for low temperature NH3-SCR with SO2 resistance were investigated via in-situ DRIFTS, SO2-TPD and FTIR. The activity results indicated that Fe and Co co-doped catalyst with an Fe/Co molar ratio of 2:4 (2Fe4Co-MCT) showed excellent SO2 resistance (98% NO conversion) at 200 °C when compared to the Mn-Ce/TiO2 catalyst. In-situ DRIFTS and SO2-TPD results showed that SO2 reacted with NH3 to form (NH4)2SO4 or NH4HSO4 as reversible deactivation blocking the active sites. Moreover, SO2-TPD results further implied that irreversible deactivation of Mn-Ce/TiO2 occurred by SO2 due to the formation of thermal stable sulfated species (MnSO4, Ce(SO4)2 or Ce2(SO4)3) to reduce active substances. The adsorption characteristics by in-situ DRIFTS revealed that more absorbed SO3, surface sulfite/sulfate and bulk-like sulfate species were formed on Mn-Ce/TiO2 catalyst, while Fe and Co addition to Mn-Ce/TiO2 significantly decreased the sulfur adsorption. The uniform distribution of Fe and Co on the Mn-Ce/TiO2 surface stopped SO2 diffusing to the inner layer of catalyst. In-situ DRIFTS also illustrated that the SCR reaction over 2Fe4Co-MCT catalysts mainly followed by Eley–Rideal (E–R) mechanism in the presence of SO2, which the adsorbed NH3 and NH4+ species reacted with gaseous NO species to produce unstable NH4NO2 and then rapidly decomposed into N2 and H2O.

In this study, the physical properties of refractory BC (rBC) including mass concentration, core size distribution and mixing state were in-situ characterized with a single particle soot photometer (SP2) at a polluted rural site in the North China Plain in November 2018. The average rBC mass concentration is 4.12 ± 2.47 μg m−3, accounting for 6.26% of PM1 mass. Its diurnal variation shows that the rBC concentration is affected by both the local residential activities and the evolution of planetary boundary layer (PBL). And a broader rBC core mass size distribution (CMSD) can be observed in the afternoon. The CMSD show a primary mode with peak diameter (Dm) of ~222 nm, and a small secondary mode with Dm of ~687 nm. The average absolute coating thickness (ACT) of rBC particles is 50 nm and the bulk relative coating thickness (BRCT) is about 1.7, indicating a relatively high aging level of rBC. The correlation analysis between SP2-separated rBC and PMF-separated OA factors indicate that rBC with different core size (Dc) and ACT may be originated from different sources. The rBC contributed by coal combustion is distributed throughout a large Dc range (~70–500 nm). The rBC particles emitted by traffic sources have small core sizes and thin coating thickness (Dc < 180 nm and ACT 250 nm). In addition, the secondary mode of rBC particles are likely to be originated from coal combustion.

Effective density is one of the most important physical properties of atmospheric particles. It is closely linked to particle chemical composition and morphology, and could provide special information on particle emissions and aging processes. In this study, size-resolved particle effective density was measured with a combined DMA-CPMA-CPC system in Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain (McFAN) in autumn 2019. With a new developed flexible Gaussian fit algorithm, frequent (77–87 %) bimodal distribution of particle effective density is identified, with a low-density mode (named sub-density mode) accounting for 22–27 % of total observed particles. The prevalence of the sub-density mode is closely related to fresh black carbon (BC) emissions. The geometric mean for the main-density mode (eff,main) increases from 1.18 g cm−3 (50 nm) to 1.37 g cm−3 (300 nm) due to larger fraction of high-density components and more significant restructuring effect at large particle sizes, but decreases from 0.89 g cm−3 (50 nm) to 0.62 g cm−3 (300 nm) for the sub-density mode (eff,sub) ascribed to the agglomerate effect. eff,main and eff,sub show similar diurnal cycles with peaks in the early afternoon, mainly attributed to the increasing mass fraction of high material density components associated with secondary aerosol production, especially of secondary inorganic aerosol (SIA). To investigate the impact of chemical composition, bulk particle effective density was calculated based on measured chemical composition (ρeff,ACSM) and compared with the average effective density at 300 nm (eff,tot,300 nm). The best agreement between the two densities is achieved when assuming a BC effective density of 0.60 g cm−3. The particle effective density is highly dependent on SIA and BC mass fractions. The influence of BC on the effective density is even stronger than SIA, implying the importance and necessity of including BC in the estimate of effective density for ambient particles.

Vertical measurements of aerosol physical-chemical properties have important significance for better addressing the environment and climate effects of atmospheric aerosol. Traditional in-situ vertical observations of those properties are mainly based on aircraft platforms which are costly and restrictive, and not applicable for near-ground (

Effective density is one of the most important physical properties of atmospheric aerosol particles, and is linked to particle formation and aging process. Combined characterization of aerosol density, chemical composition, emission and aging processes may provide crucial information for better understanding their interactions and effects on environment and climate. In autumn of 2019, the effective density of sub-micrometer aerosol particles was measured in-situ at a heavily polluted rural site in the North China Plain (NCP). A tandem technique coupling a Centrifugal Particle Mass Analyzer (CPMA) with a differential mobility analyzer (DMA) and a Condensation Particle Counter (CPC) were used to determine the effective density of ambient aerosol particles with diameters of 50, 100, 150, 220 and 300 nm. The probability distribution of effective density exhibits double peak modes in majority cases, with a higher density mode (main-density) and a lower density mode (sub-density). The existence of sub-density particles normally ascribed to freshly emitted or partial aged black carbon (BC) with non-spherical morphology. The number fraction of sub-density mode varies from 4% to 67%, with mean of 22-27% at five particle sizes. Due to the higher aging degree of larger particles, the main-density exhibits an evident ascending trend with particle size. However, the sub-density decreases as mobility size increases, from 0.89 g/cm3 at 50 nm to 0.62 g/cm3 at 300 nm, since larger fresh soot particles usually present a more agglomerated morphology than small particles. A comparison was carried out between the mean effective density at 300 nm and ACSM-derived density using different approximations of BC density. The best agreement is achieved when assuming a BC density of 0.6 g/cm3, indicating that BC typically exists as non-spherical particles with fractal-like or porous morphology in the NCP in cold season.

Black carbon (BC) is the most important light-absorbing species in the atmosphere and has a strong positive direct radiative forcing. In-cloud scavenging is the major way to wash out BC from the atmosphere. Understanding the connection between its physico-chemical properties and scavenging efficiency is therefore a key to evaluate its lifetime, atmospheric burden and spatial distribution. During an intensive field campaign conducted in the North China Plain in 2019, a ground-based counterflow virtual impactor was utilized to separate fog droplets in radiation fog events. BC mass and mixing state of fog droplet residues were online measured with a single particle soot photometer (SP2). In a strong radiation fog event with visibility of about 50 m, more than 20% fog droplets are found to contain a BC core. BC scavenging efficiency is found to be strongly determined by its diameter and mixing state. Driven by different mechanisms, higher scavenging efficiencies up to 10% are observed for larger and smaller BC particles, and the minimum efficiency is found at BC diameter of 120 nm. For large core (>120 nm) BC-containing particles, the scavenging efficiency increases significantly with coating thickness (CT), from about 10% for CT300 nm. Chemical composition may also be a key parameter influencing the scavenging of BC. Based on the observation of 3 fog events, parameterizations of BC scavenging efficiency are also given in this study.

Effective density is one of the most important physical property of atmospheric aerosols, which is link to particle formation and aging process. Combined characterization of density, chemical composition and source evolution of aerosol is crucial for understanding their interactions and effects on environment and climate. The effective density of sub-micrometer aerosol particles was investigate at a heavily polluted rural site in the North China Plain from 16 October to 1 November 2019. A tandem technique coupling a Centrifugal Particle Mass Analyzer (CPMA) with a differential mobility analyzer (DMA) and a Condensation Particle Counter (CPC) were used to determine the effective density of ambient aerosol particles with selected diameters of 50, 100, 150, 220 and 300 nm. The measured effective density is higher during clean period than pollution period, with average values ranged from 1.13 to 1.36 g/cm3, which is lower than the reported values in Shanghai and Beijing. Similar diurnal cycles of effective density are observed for the five diameters, that is, started to increase in the morning and reached a peak in the afternoon around 13:00-16:00, then decreased and remained at a relative low value during the night. Two valleys are found during morning and evening rush hours for particle diameter smaller than 150 nm, which is likely to stem from the higher fresh emissions such as BC, BBOA and HOA. In most cases, measured particle effective density shows a single-modal distribution. But during clean days, bimodal distribution was observed with an extra low-density mode peaking at around 0.5 -1.0 g/cm3, which may be attributed to freshly emitted soot particles.

Black carbon (BC) is the most important light absorbing component in the atmosphere and has significant impacts on the climate, environment and public health. Its effects depend not only on its spatial-temporal distribution, but also on its physico-chemical characteristics. Mixing state is one of the most important properties of BC and strongly determines its hygroscopicity and radiative properties. During an intensive field campaign conducted in the North China Plain in winter 2018, mass-based mixing state of BC-containing particles were online measured with a Centrifugal Particle Mass Analyzer and Single Particle Soot Photometer (CPMA-SP2) tandem system. This technique directly provides the mass ratio of non-refractory coating matter to BC core (MR) in individual particles and does not require to assume the density, morphology and refractive index of BC core and coating in data retrieval, therefore has lower uncertainly compared with leading-edge fit technique. In our measurement, the mean number fraction of uncoated (MR=0), thin coated (0RR≥3) BC-containing particle during the campaign were respectively ~10%, ~35% and ~55%, indicating the strong aging process of BC-containing particle in the North China Plain. The median value of MR was much higher in polluted days than clean days, for example, the median value of MR with a particle mass of 8.56 fg (~220 nm in diameter) for polluted and clean days were ~3.2 and ~1.6, respectively. The mixing state of BC-containing particles obtained by different methods were also compared and evaluated.

Fe and Co co-doped Mn-Ce/TiO2 (MCT) catalysts were investigated for the simultaneous removal of nitric oxide (NO) and elemental mercury (Hg0) at reaction temperature lower than 200 °C. The catalysts were characterized by Brunauer–Emmett–Teller (BET), temperature program reduction (TPR), scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. The experimental results showed that the co-doped 2Fe4Co-MCT catalyst exhibited better performance for the simultaneous removal of NO and Hg0 compared to Fe or Co doped catalysts. This could be due to higher BET surface area and better redox property of 2Fe4Co-MCT catalyst. In addition, we propose that chemisorbed O2 played a dominant role in selective catalytic reduction (SCR) of NO while lattice O2 played a key role in Hg0 oxidation. The results also indicate that the introduction of Fe species enhanced the activity of SCR, whereas the introduction of Co species enhanced the oxidation of Hg0. The synergistic effect of Fe and Co species in the 2Fe4Co-MCT catalyst are also suggested to be an important mechanism for simultaneously removing NO and Hg0.

Osteoclasts are responsible for bone resorption caused by bone microstructural damage and bone-related disorders. Evidence shows that tanshinone IIA (Tan‑IIA), a traditional Chinese medicine, is used clinically as a drug for the treatment of cardiovascular and cerebrovascular diseases. However, the efficacy and mechanism underlying the effect of Tan‑IIA on the viability of osteoclasts remain to be fully elucidated. The present study investigated the therapeutic effects of Tan‑IIA on osteoblast differentiation and oxidative stress in vitro and in vivo. Cell viability was analyzed and oxidative stress was examined in the osteoblasts. Wnt1sw/sw mice were used to investigate the therapeutic effects of Tan‑IIA on spontaneous tibia fractures and severe osteopenia. The bone strength, collagen and mineral were examined in the tibia. Osteoblast activity was also analyzed in the experimental mice. The Tan‑IIA‑induced differentiation of osteoclasts and the mechanism of action were investigated in osteocytes. The data showed that Tan‑IIA treatment improved cell viability. The data also demonstrated that Tan‑IIA decreased the levels of H2O2, accumulation of reactive oxygen species and apoptosis of osteoblasts. Tan‑IIA inhibited the deleterious outcomes triggered by oxidative stress. In addition, Tan‑IIA inhibited the activation of nuclear factor (NF)‑κB and its target genes, tumor necrosis factor (TNF)‑α, inducible nitric oxide synthase and cyclooxygenase 2, and increased the levels of TNF receptor‑associated factor 1 and inhibitor of apoptosis protein‑1/2 in the osteocytes. Furthermore, it was shown that Tan‑IIA reduced the propensity to fractures and severe osteopenia in mice with osteoporosis. Tan‑IIA also exhibited improved bone strength, mineral and collagen in the bone matrix of the experimental mice. It was found that the Tan‑IIA‑mediated benefits on osteoblast activity and function were through the NF‑κB signaling pathway. Taken together, the data obtained in the present study suggested that Tan‑IIA had protective effects against oxidative stress in osteoblastic differentiation in mice with osteoporosis by regulating the NF‑κB signaling pathway.

MotivationFacing data quickly accumulating on protein sequence and structure, this study is addressing the following question: to what extent could current data alone reveal deep insights into the sequence-structure relationship, such that new sequences can be designed accordingly for novel structure folds?ResultsWe have developed novel deep generative models, constructed low-dimensional and generalizable representation of fold space, exploited sequence data with and without paired structures, and developed ultra-fast fold predictor as an oracle providing feedback. The resulting semi-supervised gcWGAN is assessed with the oracle over 100 novel folds not in the training set and found to generate more yields and cover 3.6 times more target folds compared to a competing data-driven method (cVAE). Assessed with structure predictor over representative novel folds (including one not even part of basis folds), gcWGAN designs are found to have comparable or better fold accuracy yet much more sequence diversity and novelty than cVAE. gcWGAN explores uncharted sequence space to design proteins by learning from current sequence-structure data. The ultra fast data-driven model can be a powerful addition to principle-driven design methods through generating seed designs or tailoring sequence space.AvailabilityData and source codes will be available upon request.Contactyshen@tamu.eduSupplementary informationSupplementary data are available atBioinformaticsonline.

With the consumption of energy, blackouts, and a series of social development problems, the discussion of energy security has become the focus of international attention. This paper aims to construct a universal multidimensional index system from four dimensions, and compare the energy security systems of different countries by measuring the Energy Security Index (ESI) of 19 countries of G20 and analyzing their evolution characteristics. The results of this paper show that the ESI of the G20 countries is increasing, the number of dangerous countries is decreasing, mainly concentrated in the Asian and African regions, and environmental sustainability and safety use are the main factors affecting their energy security. The security countries are mainly concentrated in the developed countries of the Americas and Europe. Since 1995, the ESI of China has continued to rise and now China is a generally safe country, which reflects China&rsquo, s continuous optimization of energy structure and continuous improvement of the relationship of energy systems and economic, population, and environmental systems.

To evaluate the influence of nicotine intake on bone microstructure, bone biomechanics, and oxidative stress state in rats.Thirty-six 6-week-old male Sprague Dawley rats (weight, 160-180 g) were randomly divided into control group, low dose group, and high dose group, 12 rats each group. The rats in high dose group and low dose group were given respectively 6.0 mg/kg and 0.4 mg/kg nicotine gavage intervention for 12 months; no intervention was made in the control group. The survival of rats was observed during experiment, and the weight of rats was measured every month. At 12 months after modeling, the L1 vertebral body was harvested to measure the bone mineral density (BMD), bone volume fraction (BVF), trabecular thickness (TT), trabecular number (TN), and trabecular spacing (TS) by Micro-CT three-dimensional reconstruction; the left femur was harvested for biomechanical tests of maximal load, stiffness, and the maximal fracture energy; and arterial blood was extracted to measure the malonyldialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and cotinine.During the experiment, two rats and one rat were added in the high dose group and the low dose group because of death, and no death in the control group. The body weight of the rats in the high and low dose groups gradually decreased with time when compared with one in the control group, and significant difference was found between two dose groups and the control group at 8-12 months (Nicotine intake can cause micro-structural changes of the bone, decreased bone mechanical properties, and imbalance of oxidation-antioxidant levels in rats. High-dose nicotine intake may be one of the causes of osteoporosis.探讨长期尼古丁摄入对大鼠骨内微结构、骨生物力学性能以及氧化应激状态的影响。.取6周龄雄性SD大鼠36只，体质量160～180 g，随机分为3组，分别为对照组、低剂量组和高剂量组，每组12只。高剂量组和低剂量组分别按照每天6.0、0.4 mg/kg标准尼古丁灌胃干预，持续12个月；对照组不作处理。实验期间观察各组大鼠存活情况，每个月大鼠称重。造模12个月后处死全部大鼠，取L1椎体进行Micro-CT三维重建测量骨密度（bone mineral density，BMD）、骨体积分数（bone volume fraction，BVF）、骨小梁厚度（trabecular thickness，TT）、骨小梁数目（trabecular number，TN）、骨小梁间隙（trabecular spacing，TS），取左侧股骨干进行生物力学测试最大载荷、抗弯刚度、最大断裂能；取动脉血检测丙二醛（malonyldialdehyde，MDA）、超氧化物歧化酶（superoxide dismutase，SOD）、过氧化氢酶（catalase，CAT）以及可替宁含量。.实验期间，高剂量组死亡2只大鼠，低剂量组死亡1只，对照组大鼠均存活。随时间延长，高、低剂量组大鼠体质量逐渐低于对照组，8～12个月时，高、低剂量组与对照组比较差异有统计学意义（长期尼古丁摄入会引起大鼠骨内微结构改变、骨生物力学性能下降以及氧化-抗氧化水平失衡，长期高剂量尼古丁摄入可能是导致骨质疏松症发生的原因之一。.

Objective: In 2010, only 1 donor blood sample was found to be anti-hepatitis C virus (HCV) negative and HCV RNA positive, as detected by nucleic acid testing. In occult HCV infection (OCI), HCV RNA is found in peripheral blood mononuclear cells (PBMCs). We investigated the prevalence of OCI among blood donors. Methods: We collected 513 samples from 334 eligible and 179 deferred donors, including 55 anti-HCV-positive, 113 alanine aminotransferase (ALT)-elevated, and 11 hepatitis B virus surface antigen (HBsAg)-positive blood donors. PBMCs were isolated, the 5′-untranslated region of HCV RNA was amplified by reverse transcription nested PCR, and the genotype of the core region was determined. Results: No HCV RNA was detected among the eligible samples. Among the deferred donors, 15 (27.2%) had detectable HCV RNA in 55 anti-HCV PBMC specimens. HCV RNA was detected in 1 (9.1%) HBsAg-positive and 9 (8%) ALT-elevated samples. The prevalence of OCI in the blood donors was 2.2% (10/458). HCV genotypes were determined in 10 subjects, indicating that 2 (20.0%) were subtype 2a, 7 (70.0%) were 1b, and 1 (10%) was 6a. Conclusions: This study showed that OCI does exist among Chinese blood donors. However, to determine the epidemiology and outcome of this HCV infection, further follow-up with more participants and patients receiving blood components with OCI is needed.

BACKGROUND Screening of blood donors for antibody to human immunodeficiency virus Types 1 and 2 (anti-HIV-1/2) and/or HIV nucleic acid test (NAT) is a well-established venue to prevent HIV transfusion-transmitted disease. However, with the current available technologies, HIV testing may result in donor loss due to false-positive results. This study intended to establish a donor reentry procedure for HIV screening–reactive donors in China. STUDY DESIGN AND METHODS From September 1, 2013, to August 31, 2014, a total of 465 donors from 14 Chinese blood centers were enrolled in this study. Enrollment criteria include all donors who were screened reactive or belonged to the “gray zone” by enzyme-linked immunosorbent assay and/or reactive by NAT when tested at the local blood centers. All donor samples were sent to a central HIV confirmation laboratory where anti-HIV-1/2 and HIV individual-donation NATs were conducted. If the results were reactive for anti-HIV-1/2, then the samples were tested with a recombinant immunoblot assay. RESULTS Based on the repeat testing at the central HIV confirmation laboratory 8 or 16 weeks after the study, 252 donors of 465 (54.2%) who completed the study could be classified in two categories for HIV status: 45 (18%) true positive and 207 (82%) false positive. A total of 213 of 465 (45.8%) donors were lost on follow-up and, thus, their HIV status cannot be determined with certainty. Based on these data, a donor reentry procedure was proposed. CONCLUSION Based on our proposed donor reentry procedure for HIV screening–reactive donors, a majority of screening-positive donors (82%, 207/252) can be reentered safely.

Power grid as an important infrastructure which ensures the healthy development of economy and society and accurate and reasonable prediction of the power grid investment demand has always been the focus problem of the power planning department and the power grid enterprises. In view of the complex nonlinear and nonstationary characteristics of the power grid investment demand sequence, a novel hybrid EMD-GASVM-RBFNN forecasting model based on empirical mode decomposition (EMD) method, support vector machines optimized by genetic algorithm (GA-SVM) model, and radial basis function neural network (RBFNN) model is proposed. Firstly, the EMD method is used to decompose the original power grid investment data sequence into a series of IMF components and a residual component which have stronger regularity compared with the original data. Then, according to the different characteristics of each subsequence, the GA-SVM and RBFNN model will be used to forecast different subsequences, respectively. Next, the prediction results of different subsequences are aggregated to obtain the final prediction results of the power grid investment. Finally, this paper dynamically simulates China’s power grid investment from 2018 to 2020 based on the EMD-GASVM-RBFNN hybrid forecasting model and Monte Carlo method.

The risk of transfusion-transmitted malaria is a major concern in many countries. This study investigated the prevalence of malaria antibodies and parasitemia in eligible blood donors in Jiangsu, in Eastern China. Malaria antibodies were detected in 2.13% of the 704 plasma samples studied. We found that the prevalence of malaria antibodies was not significantly correlated with gender, occupation and frequency of donation, but it increased with age. No Plasmodium was observed in red blood cells and no Plasmodium DNA was detected in any of the antibody-positive samples. The prevalence of malaria antibodies was not higher than expected in Eastern China.

Background Hepatitis B infections, characterized by the presence of a viral genome without detectable hepatitis B surface antigen (HBsAg; Occult hepatitis B infection [OBI]), have been reported recently. Objectives We performed serological and molecular characterization of OBI among blood donors at Jiangsu province blood center during years 2013 and 2014. Methods All donor samples were routinely screened by double enzyme-linked immunosorbent assay (ELISA) for hepatitis C virus (HCV), hepatitis B virus (HBV), human immunodeficiency virus (HIV), Treponema pallidum (TP), and alanine aminotransferase (ALT). Single-reactive, nonreactive, and ALT-elevated samples were pooled or resolved by nucleic acid testing (NAT). Seromarkers were examined in HBsAg-/DNA+ samples. After 1 to 12 months of follow up, seromarkers were screened again to verify OBI samples. Results We studied 157119 samples from blood donors. A total of 154397 ELISA nonreactive donor samples were identified, and HBV DNA was detected in 81 samples; no samples were positive for HIV or HCV RNA. Hepatitis B virus viral loads in most donors were less than 20 - 200 IU/mL. There was only one HBsAg-positive sample. Eighty HBsAg-/DNA+ samples were evaluated further. Of these samples, 85% (68/80) were reactive for anti-HBc and 36.2% (29/800) were reactive for anti-HBc and anti-HBs; 11.3% (9/80) did not have any detectable serological markers. Twenty-nine donors were followed up. One was HBsAg ELISA positive, and of six seronegative donors, all had anti-HBc and anti-HBs, but were negative for DNA. Samples were HBV genotypes B, C and D. Mutations in the S region of HBV DNA included S114T, G119R, P120S, T125M, C139Y, T140I, C147W, T148A, A159V/G, E164D, V168A, and R169C. Conclusions Overall, we found that OBI was rare, but that the prevalence of OBI was slightly higher in Jiangsu than in other areas of China.

Platelet glycoprotein Ib (GPIb) is a primary adhesion receptor and involved in platelet-related disorders. However, it is difficult to study GPIb-specific platelet stimulation using physiological ligands in vivo. GPIb-binding snake C-type lectins (snaclecs) are useful tools for exploring GPIb in vitro because they act on platelets differently. In the present study, a novel GPIb-binding snaclec, named jerdonibitin, was purified, molecular cloned and characterized from Trimeresurus jerdonii venom. On SDS-polyacrylamide gel electrophoresis, it showed a single band with an apparent molecular weight of 25 kDa under non-reducing conditions and two distinct bands with apparent molecular weights of 15 kDa (α-subunit) and 13 kDa (β-subunit) under reducing conditions. The cDNA sequences of each subunit of jerdonibitin were identified and both deduced amino acid sequences were confirmed by N-terminal protein sequencing and trypsin-digested peptide mass fingerprinting of MALDI-TOF. Sequence alignment showed that jerdonibitin is a snaclec and has sequence similarity with TSV-GPIb-BP (a GPIb-inhibitory snaclec). Jerdonibitin dose-dependently inhibited platelet aggregation induced by ristocetin or low-dose thrombin, but not by high-dose thrombin. The GPIbα was detected by affinity chromatography on jerdonibitin. In vivo, jerdonibitin also dose-dependently induced thrombocytopenia of mice and platelet counts remained at very low level after 18 h intravenous injection. In summary, a novel GPIb-inhibitory snaclec was molecular cloned and characterized, which might provide insights into investigation of how GPIb-inhibitory snaclecs work and development of new antiplatelet agents.

With the continuous maturity of China's power grid as well as the advancement of electricity market reform in China, accurate and efficient investment decision has become an inevitable requirement of power grid enterprises. However, China's Power grid investment demand has complicated nonlinear and non-stationary characteristics due to it's complex causes of formation, thus make it hard to be forecasted. Aiming at this problem, this paper puts forward a novel hybrid VMD-RELMLOO-PSOSVM forecasting model based on variational mode decomposition (VMD), leave-one-out cross validation error based optimal regularized extreme learning machine (RELM-LOO) and support vector machines optimized by particle swarm optimization algorithm (PSO-SVM). Firstly, the VMD method is employed to decompose the original power grid investment data sequence into several modes which have specific sparsity properties while producing main signal. Then, according to the different characteristics of each subsequence, the RELM-LOO and PSO-SVM model will be used to forecast different modes, respectively; Next, the prediction results of all modes are aggregated to obtain the final prediction results of China's power grid investment demand. Finally, this paper predicts China's power grid investment demand from 2018 to 2020 under 5 different scenarios based on the proposed VMD-RELMLOO-PSOSVM hybrid forecasting model.

Screening of blood donors for antibody to human immunodeficiency virus Types 1 and 2 (anti-HIV-1/2) and/or HIV nucleic acid test (NAT) is a well-established venue to prevent HIV transfusion-transmitted disease. However, with the current available technologies, HIV testing may result in donor loss due to false-positive results. This study intended to establish a donor reentry procedure for HIV screening-reactive donors in China.From September 1, 2013, to August 31, 2014, a total of 465 donors from 14 Chinese blood centers were enrolled in this study. Enrollment criteria include all donors who were screened reactive or belonged to the "gray zone" by enzyme-linked immunosorbent assay and/or reactive by NAT when tested at the local blood centers. All donor samples were sent to a central HIV confirmation laboratory where anti-HIV-1/2 and HIV individual-donation NATs were conducted. If the results were reactive for anti-HIV-1/2, then the samples were tested with a recombinant immunoblot assay.Based on the repeat testing at the central HIV confirmation laboratory 8 or 16 weeks after the study, 252 donors of 465 (54.2%) who completed the study could be classified in two categories for HIV status: 45 (18%) true positive and 207 (82%) false positive. A total of 213 of 465 (45.8%) donors were lost on follow-up and, thus, their HIV status cannot be determined with certainty. Based on these data, a donor reentry procedure was proposed.Based on our proposed donor reentry procedure for HIV screening-reactive donors, a majority of screening-positive donors (82%, 207/252) can be reentered safely.

Carbon nanotubes (CNTs) can be used to compound poly (methyl methacrylate)/carbon nanotube (PMMA/CNT) composites by an in situ process. The experimental results show that CNTs can be initiated by AIBN to open their π-bonds, which imply that CNTs may participate in PMMA polymerization and form a strong combining interface between the CNTs and the PMMA matrix. Through the use of an improved in situ process, the mechanical properties and the heat deflection temperatures of composites rise with the increase of CNTs. The dispersion ratio of CNTs in the PMMA matrix is proportional to the reaction time of polymerizing MMA before CNTs are added into the PMMA mixture.

To compare the biomechanical characteristics of the less invasive stabilization system (LISS) and the dynamic condylar screw (DCS) in the fixation of subtrochanteric fractures of the femur so as to provide theoretical basis for choosing internal fixator in clinical application.Twelve cadaveric human femurs (35-50 years old) were selected with similar proximal femur, excluding deformities, fractures, and other lesions. The twelve femur specimens were randomly divided into 2 groups, 6 specimens per group. An 1 cm gap of osteotomy model was made in the proximal femur up to 1 cm below the lesser trochanter to simulate a comminuted subtrochanteric fracture of femur, and the distal end was embedded with denture acrylic and liquid for denture acrylic. Fracture was fixed by LISS in group A, and was fixed by DCS in group B. The specimens were fixed on Instron-8874 servo-hydraulic mechanical testing machine in a single-leg standing position, and the axial compression test and dynamic fatigue test were carried out to compare the compressive strength and the strain distribution at both sides of the fracture line.Axial compression test: the strain values of the 2 strain gauges in group A were significantly smaller than those in group B (P0.01); the vertical down displacement of the femoral head in group A was significantly smaller than that in group B (P0.01) under the same load; when the load was 600 N, the axial rigidity of group A was (209.06 +/- 18.63) N/mm, which was significantly higher than that of group B [(65.79 +/- 7.26) N/mm] (t = 3.787, P = 0.004). Dynamic fatigue test: the vertical down displacement of the femoral head in group A was significantly smaller than that in group B in the same cyclic loading cycle (P0.01); when the vertical down displacement of the femoral head was 0.5 mm, the force and the cyclic loading cycles in group A were significantly larger than those in group B (P0.01).LISS, which has good mechanical stability, can meet the requirements for subtrochanteric fracture of femur fixation in biomechanics and anatomical structures. It can be proven that the LISS internal fixator is firmer than the DCS internal fixator by biomechanical comparison.