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As a convenient and effective surface modification approach, non-thermal atmospheric pressure plasma (NTAPP)can be used to improve dentin bonding, and has recently become a research focus. Studies have shown that NTAPP can alter dentin surface properties, improve the penetration and polymerization of adhesives, stimulate the cross-linking of collagen, and change the micro-morphology and element content of dentin surface, thus improve the dentin bonding quality. This article introduces the current research progress in the application of NTAPP in the field of dentin bonding, in order to provide innovative information for future research in optimization of the quality of dentin bonding.低温常压等离子体（non-thermal atmospheric pressure plasma，NTAPP）是一种简便、有效的表面改性技术，近年成为提高牙本质粘接质量的研究热点。NTAPP能通过改变牙本质表面性质促进粘接剂渗透及聚合、促进胶原交联以及改变牙本质表面微观形貌和元素含量，改善牙本质粘接质量。本文就NTAPP于牙本质粘接领域的应用进展作一综述，以期为牙本质粘接的优化研究提供参考。.

Pennycress (Thlaspi arvense L.), an annual herb of the mustard family Brassicacae, is native to Eurasia and now widely distributed throughout temperate North America. This species is currently being developed as a medicinal herb used to treat nephritis in China and an oilseed crop for biofuel production (Roque et al.2012). In November 2020, stunt and wilt symptoms were observed on above ground parts and swollen club-shaped galls were observed on the roots of T. arvense in most of the Chinese cabbage growing area in Kangding (30°03'"N,102°02'"E), Sichuan Province of China. The average disease incidence of swollen roots on T. arvense was 91.2% ( n=80). To identify the causal agent of this disease, the swollen roots of T. arvense were collected, crushed and observed under microscope (Fei et al.2017). Abundant resting spores were found in the root galls, which were spherical and 2.0 to 3.1 μm in diameter with an average length of 2.7 nm (n=100). The healthy roots and the root galls of T. arvense plants were further evaluated by PCR with P. brassicae-specific primers TC2F/TC2R (Cao et al. 2007). The results showed that a DNA fragment with an estimated size of 520 bp, as expected for that of P. brassicae, was consistently amplified in diseased roots, No PCR amplification occurred in the healthy roots with the TC2F/TC2R primers. Blast analysis of the 520 bp segment (GenBankMZ040496) showed the highest identity with the sequence of small subunit ribosomal RNA gene of P. brassicae (GenBankMH762161, 97.7%, E value=0). These results confirmed that the pathogen in the galled roots of T. arvense was P. brassicae. The pathogenicity of isolated P. brassicae was tested on both T. arvense and Chinese cabbage (B. campestris ssp. pekinensis). Resting spores were isolated from the diseased roots (Castlkbury et al. 1994) of T. arvense and suspended in Hoagland's solution to the final concentration of 1 × 107 spores per milliliter. Fifteen plastic pots (10 cm bottom diameter, 16 cm upper diameter, 13 cm high) were filled with soil (1 kg per pot) that was sterilized twice with high-temperature (121℃), high pressure (19 PSI) for 1.5 hours with a time interval of 2 days between. Inoculated pots received 100 mL spore suspension each. Fifteen control pots with sterilized field soil were treated with 100 mL Hoagland's solution each. Seeds of T. arvense and B. campestris were pre-germinated at 20°C on moist filter paper for 7 days and transplanted into the pots, five seedlings each and five pots per treatment. The pots were maintained in a greenhouse with 16 hours photoperiod at 24°C/16°C day/night temperature. After 7 weeks, plants in each pot were uprooted and the roots cleaned in running water and inspected for clubroot symptoms. Plants of T. arvense and Chinese cabbage in pots inoculated with resting spores showed clubroot symptoms while no disease symptoms were observed on any control plants. The disease incidence rate was 95.4% on T. arvense and 81.2% on B. campestris. Therefore, it was confirmed that P. brassicae could cause clubroot disease on T. arvense. To our knowledge, this is the first published report of clubroot disease on T. arvense in China. This finding is helpful for the management of clubroot on herbs and plants of biological origin in the cruciferous family.

Insulin-like growth factor binding protein 5 (IGFBP5) is broadly bioactive, but its role in osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs) remains to be clarified. Here, we demonstrated that IGFBP5 expression was markedly increased during the early osteogenic differentiation of hMSCs. We then over-expressed and knocked down this gene in hMSCs and evaluated the impact of manipulation of IGFBP5 expression on osteogenic differentiation based upon functional assays, ALP staining, and expression of osteogenic markers. Together, these analyses revealed that IGFBP5 over-expression enhanced early osteogenic differentiation, as evidenced by increased ALP staining and osteogenic marker induction, whereas knocking down this gene impaired the osteogenic process. Over-expression of IGFBP5 also markedly bolstered the extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation level, while IGFBP5 knockdown suppressed this signalling activity. We additionally compared the impact of simultaneous IGFBP5 overexpression and ERK1/2 inhibitor treatment to the effect of IGFBP5 over-expression alone in these hMSCs, revealing that small molecule-mediated EKR1/2 inhibition was sufficient to impair osteogenic differentiation in the context of elevated IGFBP5 levels. These findings indicated that IGFBP5 drives the early osteogenic differentiation of hMSCs via the ERK1/2 signalling pathway. Our results offer value as a foundation for future efforts to study and treat serious bone-related diseases including osteoporosis.

Due to the relatively high flux levels available in FT-IR spectrophotometers and the universal need for better signal to noise ratios, detectors are often operated in conditions under which their responsivity varies during the measurement. This can happen both during a single measurement (nonlinearity) as well as between measurements (nonequivalence). The results of measurements made under these conditions will contain errors. The quantity and spectral distribution of the errors will depend on both the instrument signature and the sample properties under investigation.

Cold stress is one major threats to field crops. The cold tolerant ability is a key limiting factor for the popularization of peanut (Arachis hypogaea L.) in cold areas. Our previous research showed three key metabolic change time points of peanut buds in response to low temperature. The present study applied iTRAQ proteomic to further quantify differentially expressed proteins in three key metabolic change time points. A total of 2684 non-redundant proteins and 333 differentially expressed proteins across the three cold stress treatment points were identified. The results enrich the cold stress regulation network and provide useful information for further improving the ability of peanut under cold stress.

We report an experimental investigation of a laser-gas-converter approach for generating high-yield ultrashort MeV positrons. We observe that MeV electrons with a high charge of several tens of nC can be well generated by a ∼ 6 J , ∼ 40 f s laser interacting with a high-density gas jet. However, it is shown that the propagation of the highly charged electron beam is significantly inhibited because the electrons are reflected by the sheath potential in the density decreasing region of the gas target, thus leading to a low positron yield. Consequently, by using an integrated nozzle-converter design to eliminate the density falling ramp of the gas target such that the electron refluxing is inhibited, we observe a significant enhancement of positron yield (up to a factor of 15), finally reaching a positron yield of 5 × 10 8 s r − 1 . This high-yield ultrashort MeV positron may have great potential toward the simulation of astrophysical pair plasma.

To investigate the effects of dexmedetomidine (Dex) treatment administered at various times on acute lung injury (ALI).Thirty Wistar rats were randomly divided into five groups (n = 6/group). Lipopolysaccharide (LPS) was intraperitoneally injected into the rats in the LPS, Dex1, Dex2, and Dex3 groups to induce ALI, while the control group (C) was left untreated. Rats in the Dex1 group were intraperitoneally administered with 50 µg/kg Dex 30 minutes before modeling. Rats in the Dex2 group were injected with 25 µg/kg Dex 30 minutes before modeling and two hours after. Rats in the Dex3 group received 50 µg/kg Dex two hours after modeling. The animals in the C and LPS groups were given an equal volume of saline. The wet-to-dry (W/D) weight ratio of the rats' lungs was calculated, and pathological alterations in lung tissues were observed. The concentrations of inflammation-related factors and the expression of Janus kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), and matrix metallopeptidase 9 (MMP9) were measured.The W/D ratio, expression of inflammatory factors, and expression of JAK1, STAT3, and MMP9 were significantly increased in the ALI rats (p0.05) compared with the C group. The level of anti-inflammatory factors in the Dex-treated groups was also significantly increased compared with the LPS group (p0.05). The concentration of anti-inflammatory factors in the Dex2 group was significantly higher than that recorded in the Dex1 and Dex3 groups (p0.05).Dex treatment administered at different times protects rats against LPS-induced ALI to varying degrees. The protective effects of Dex were most robust when administered both before and after LPS stimulation.

In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in Wuhan, China, and it subsequently spread in many countries around the world. Many efforts have been applied to control and prevent the spread of COVID-19, and many scientific studies have been conducted in a short period of time. Here we present an overview of the viral structure, pathogenesis, diagnosis, and clinical features of COVID-19 based on the current state of knowledge, and we compare its clinical characteristics with SARS and Middle East Respiratory Syndrome (MERS). Current researches on potentially effective treatment alternatives are discussed. We hope this review can help medical workers and researchers around the world contain the current COVID-19 pandemic.

Wheel hub bearing not only bears axial load but also radial load, and then its running status directly affects the performance and safety of the automobile. In particular, complicated and variable driving conditions of the automobile are not only liable to aggravate the occurrence of mechanical fault such as localized wear, but also often cause powerful intermittent interference noise. It is difficult to extract the vibration characteristics of the transient impact and harmonic components of the wheel bearings in the event of a local fault. An extraction method of fault feature based on ration of smooth and kurtosis (RSK) index and resonance-based signal sparse de-composition (RSSD) is proposed for automobile wheel hub bearings, which aims at the minimum value of RSK index, sequentially optimizes the Q-factor of the resonance sparse decomposition, and obtains its optimal value adaptively to achieve the decomposition of low resonance components with transient impact components and high resonance components with harmonic components. The effect of the method has been verified by powerful intermittent interference simulation signals and experiment signals from local fault of wheel hub bearing with periodic dynamic radial loading.

Adaptive capacity has become the focus of current research on climate change. A complete set of methods to assess the adaptive capacity for Beijing water resources was established in this study. Risk factors for water resources were identified by overlapping climate change, urbanization issues, and urban water resources, and a three-dimensional framework comprising 12 indicators specific to each risk factor was built to assess the adaptive capacity of the water resource systems. These three dimensions represent the three pillars of a sustainable water resource system: water supply, water demand, and water quality. An analytic hierarchy process was used to determine the weight for each indicator. Then a fuzzy version of the technique for order preference by similarity to an ideal solution was applied to calculate the ranking for the 11 districts in Beijing and quantify the adaptive capacity for water resources in these areas. The fuzzy approach results revealed that three indicators are key: comprehensive management capabilities for water supply, control capability for water demand, and management capabilities for water quality. Finally, adaptability proposals are proposed in accordance with the ranking results obtained.

In the Large High Altitude Air Shower Observatory (LHAASO), one square kilometer array (KM2A), with 5242 electromagnetic particle detectors (EDs) and 1171 muon detectors (MDs), is designed to study ultra-high energy gamma-ray astronomy and cosmic ray physics. The remoteness and numerous detectors extremely demand a robust and automatic calibration procedure. In this paper, a self-calibration method which relies on the measurement of charged particles within the extensive air showers is proposed. The method is fully validated by Monte Carlo simulation and successfully applied in a KM2A prototype array experiment. Experimental results show that the self-calibration method can be used to determine the detector time offset constants at the sub-nanosecond level and the number density of particles collected by each ED with an accuracy of a few percents, which are adequate to meet the physical requirements of LHAASO experiment. This software calibration also offers an ideal method to realtime monitor the detector performances for next generation ground-based EAS experiments covering an area above square kilometers scale.

The electromagnetic particle detectors (EDs) for one square kilometer detector array (KM2A) of large high altitude air shower observation (LHAASO) are designed to measure the densities and arrival times of secondary particles in extensive air showers (EASs). ED is a type of plastic scintillator detector with an active area of 1 m(2). This study investigates the design and performance of prototype ED. Approximately 20 photoelectrons are collected by the 1st dynode of a photomultiplier tube (PMT). The prototype ED exhibited good detection efficiency and time resolution. The detection for the wide dynamic particle density varying from 1 to 10 000 particles/m(2) is realized with the design of the PMT divider for the readout of both the anode and 6th dynode. (C) 2016 Elsevier B.V. All rights reserved.

Background Many CpGs become hyper or hypo-methylated with age. Multiple methods have been developed by Horvath et al. to estimate DNA methylation (DNAm) age including Pan-tissue, Skin & Blood, PhenoAge, and GrimAge. Pan-tissue and Skin & Blood try to estimate chronological age in the normal population whereas PhenoAge and GrimAge use surrogate markers associated with mortality to estimate biological age and its departure from chronological age. Here, we applied Horvath’s four methods to calculate and compare DNAm age in 499 subjects with type 1 diabetes (T1D) from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study using DNAm data measured by Illumina EPIC array in the whole blood. Association of the four DNAm ages with development of diabetic complications including cardiovascular diseases (CVD), nephropathy, retinopathy, and neuropathy, and their risk factors were investigated. Results Pan-tissue and GrimAge were higher whereas Skin & Blood and PhenoAge were lower than chronological age (p < 0.0001). DNAm age was not associated with the risk of CVD or retinopathy over 18–20 years after DNAm measurement. However, higher PhenoAge (β = 0.023, p = 0.007) and GrimAge (β = 0.029, p = 0.002) were associated with higher albumin excretion rate (AER), an indicator of diabetic renal disease, measured over time. GrimAge was also associated with development of both diabetic peripheral neuropathy (OR = 1.07, p = 9.24E−3) and cardiovascular autonomic neuropathy (OR = 1.06, p = 0.011). Both HbA1c (β = 0.38, p = 0.026) and T1D duration (β = 0.01, p = 0.043) were associated with higher PhenoAge. Employment (β = − 1.99, p = 0.045) and leisure time (β = − 0.81, p = 0.022) physical activity were associated with lower Pan-tissue and Skin & Blood, respectively. BMI (β = 0.09, p = 0.048) and current smoking (β = 7.13, p = 9.03E−50) were positively associated with Skin & Blood and GrimAge, respectively. Blood pressure, lipid levels, pulse rate, and alcohol consumption were not associated with DNAm age regardless of the method used. Conclusions Various methods of measuring DNAm age are sub-optimal in detecting people at higher risk of developing diabetic complications although some work better than the others.

Atherosclerosis, a kind of peripheral arterial disease with chronic inflammation, leads to the dysfunction of the vascular system and many other diseases. Hypoxia has been proven to participate in the progression of atherosclerosis, while curcumin can inhibit hypoxia-inducible factor 1α (HIF-1α). However, the underlying mechanisms are still elusive.qRT-PCR was used to examine the expression of HIF-1α, IL-6 and TNFα of macrophages under hypoxic condition. Western blot was applied to examine the changes of HIF-1α, ERK and p-ERK after treatment with curcumin. Oli Red O staining and enzymatic assay were used to examine the lipid and total cholesterol in macrophages, respectively. ELISA was used to examine the release of IL-6 and TNFα by macrophages. FACS and MTT assays were applied to examine the apoptosis and proliferation of macrophages.Here, we found curcumin inhibited the expression of HIF-1α at the protein level in macrophages under hypoxic condition and curcumin and HIF-1α inhibitors repressed the total cholesterol and lipid level in macrophage under hypoxic condition. Moreover, curcumin also decreased the expression of HIF-1α downstream genes, VEGF, HMOX1, ROS and PDGF. Then, the data show the HIF-1α-induced apoptosis and inflammation of macrophages were inhibited by curcumin. Curcumin also rescued the proliferation defect of macrophages caused by hypoxia. Furthermore, we found it inhibited the expression of HIF-1α via ERK signaling pathway.We describe that curcumin inhibited the HIF-1α-induced apoptosis and inflammation of macrophages via ERK signaling pathways. These results suggest curcumin can be used for the treatment of atherosclerosis.

A beam line dedicated to high-energy electron radiography experimental research with linear achromat and imaging lens systems has been designed. The field of view requirement on the target and the beam angle-position correlation correction can be achieved by fine-tuning the fields of the quadrupoles used in the achromat in combination with already existing six quadrupoles before the achromat. The radiography system is designed by fully considering the space limitation of the laboratory and the beam diagnostics devices. Two kinds of imaging lens system, a quadruplet and an octuplet system are integrated into one beam line with the same object plane and image plane but with different magnification factor. The beam angle-position correlation on the target required by the imaging lens system and the aperture effect on the images are studied with particle tracking simulation. It is shown that the aperture position is also correlated to the beam angle-position on the target. With matched beam on the target, corresponding aperture position and suitable aperture radius, clear pictures can be imaged by both lens systems. The aperture is very important for the imaging. The details of the beam optical requirements, optimized parameters and the simulation results are presented.

The ongoing Jinping Underground Nuclear Astrophysics experiment (JUNA) will take the advantage of the ultralow background in China Jinping Underground Laboratory (CJPL), high current accelerator driven by on an ECR source and highly sensitive detector to study directly a number of important reactions for the first time within their relevant stellar energy range. A 2.45 GHz ECR ion source is one of its key components to provide 10 emA H + , 10 emA He + and 2.0 emA He 2+ beams for the study of ( p , γ ), ( p,α ), ( α , p ) and ( α , γ ) reactions in the first phase of the JUNA project. Ion beam is extracted from the source with energies up to 50 kV/q. The following low energy beam transport (LEBT) system transports and matches the ion beam from the exit of ion source to the acceleration tube (AT). The design status of the ECR ion source and LEBT system for the JUNA project are presented. The potential risks of the ion source are also discussed and analysed.

The mineralogical structure of dephosphorisation slag at the first deslagging was studied by SEM–EDS, XRD and FactSage 7.0. The results show that the slag which is favourable for the enrichment of Si, Ca and P has good dephosphorisation ability. While the slag that is favourable for the enrichment of Fe and O show poor dephosphorisation ability. The main mineralogical structure in liquid slag phase is 2CaO·SiO2 and 2CaO·SiO2–3CaO·P2O5, which is favourable for dephosphorisation. The values of and increase with increasing the mole fraction of P2O5 in the solid solution phase and in the liquid slag phase, and increasing the temperature of the first deslagging. The value of increases with the increase of FeO content and slag basicity, but decreases with the increase of FeO content and basicity of solid solution phase.

Aim 5-Aminosalicylic acid is the first-line drug for mild to moderate ulcerative colitis (UC). The most commonly used 5-aminosalicylic acid is mesalamine. Several systematic reviews have demonstrated that mesalamine is effective in inducing and maintaining remission. Efficacy, safety and adherence to once daily (OD) and multiple daily (MD) dosing of mesalamine for the induction and maintenance of remission in mild to moderate UC were systematically reviewed and compared. Method PubMed, Embase and the Cochrane Central Register of Controlled Trials were searched from inception to November 2014. Only randomized controlled trials were considered eligible. STATA software (version 12.0) was used to calculate the pooled risk ratios with 95% confidence interval. Results Seventeen randomized studies containing 5439 patients were identified. No significant differences were noted in comparisons between OD and MD dosing for maintenance and induction of remission. No significant differences were noted in rates of medication adherence or adverse events between OD and MD dosing. With regard to mesalamine suppository, no significant differences were noted for comparisons between dosing regimens and adverse events for induction of remission. Conclusion OD dose of mesalamine is as effective and safe as MD doses for the induction and maintenance treatment of mild to moderate UC. OD mesalamine given as a suppository can attain the same effect and safety as MD mesalamine in inducing remission of mild to moderate ulcerative colitis.

Traditional centrifugal pumps have obvious advantages for transporting pure liquidmedia, but the existence of gas phase will cause the decline of head and efficiency, and even air blockage. Therefore, it is strongly necessary to design a gas-liquid pump with superior performance. There are various parameters that can affect the multiphase centrifugal pump performance and energy consumption. The blade outlet angle and blade number are the most critical. In this paper, CFD method is used to study the influence of outlet angle and blade number on gas-liquid transport of centrifugal pump. The results show that the boosting pressure of centrifugal impeller decreases with the increases of gas volume fraction and the boosting pressure for impeller of lower outlet angle decreases to a greater degree when the gas volume faction increases. The hydraulic performance of impeller with blade number of 6 and 8 is compared, which shows impeller with blade number of 8 has higher boosting pressure and higher efficiency than blade number of 6 under the same gas-liquid working condition. This paper will provide reference for the design of multi-phase pump to meet the requirements of gas-liquid flow.

When an intense positron burst impinges upon a target within nano or picoseconds, a pulse of gamma-rays is created. The gamma-ray pulse contains many annihilation events about the positron burst. A spatial detecting method with a detector array is able to exploit the timing information in such gamma-ray pulses by mounting many independent detector cells of the array spherically around the target. It is possible that multiple annihilated photons in the pulse will fall into the same solid angle of one detector unit, and when one more gamma-ray is detected, a multi- γ signal is generated. In this paper, the principle, the influence factors of the multi- γ signals generation and the effect of multi- γ signals on the time detection of the positron burst are studied by experiment and simulation. Furthermore, a method of eliminating multi- γ signals is also proposed and evaluated. The results can provide support for the design of the detector array applied to measure the positron lifetimes in the burst, such as the detector distance to the source and the method dealing with the multi- γ signals.

目的 探讨重型地中海贫血（地贫）患者异基因造血干细胞移植（allo-HSCT）后并发自身免疫性溶血性贫血（AIHA）诊断、治疗及转归，以提高地贫患者造血干细胞移植疗效。 方法 回顾性分析2007年7月至2017年12月共计291例行allo-HSCT重型地贫患者的临床资料。 结果 重型地贫allo-HSCT后AIHA发生率为1.72%（5/291）；AIHA中位发生时间为移植后7（5~12）个月，5例移植后AIHA患者直接和间接Coombs试验均阳性，患者主要表现为头晕、乏力、面色苍白、皮肤巩膜黄染、酱油色尿。228例HLA相合同胞供者移植患者有1例（0.43%）移植后发生AIHA，而63例非亲缘供者移植患者有4例（6.36%）移植后发生AIHA。非亲缘供者移植患者AIHA发生率高于HLA相合同胞供者移植患者。1例患者单用泼尼松治疗死亡，4例患者采用甲泼尼龙联合利妥昔单抗治疗有效，目前生存良好，其中2例Coombs试验转阴。 结论 该组重型地贫患者allo-HSCT后AIHA发生率为1.72%，Coombs试验有助于诊断移植后AIHA，非亲缘供者移植病例移植后AIHA发生率高于HLA相合同胞供者移植组，利妥昔单抗联合糖皮质激素是治疗重型地贫allo-HSCT后AIHA的有效方法。