Experimental Study on the Effect of an Organic Matrix on Improving the Strength of Tailings Strengthened by MICP.

In order to improve the effect of microbial-induced calcium carbonate precipitation (MICP) in tailings reinforcement, sodium citrate, an organic matrix with good water solubility, was selected as the crystal form adjustment template for inducing calcium carbonate crystallization, and the reinforcements of tailings by MICP were conducted in several experiments. The effects of sodium citrate on the yield, crystal form, crystal appearance, and distribution of calcium carbonate were analyzed by MICP solution test; thus, the related results were obtained. These showed that the addition of a proper amount of organic matrix sodium citrate could result in an increment in the yield of calcium carbonate. The growth rate of calcium carbonate reached 22.6% under the optimum amount of sodium citrate, and the crystals of calcium carbonate were diverse and closely arranged. Based on this, the MICP reinforcement test of tailings was carried out under the action of the optimum amount of sodium citrate. The microscopic analysis using CT and other means showed that the calcium carbonate is distributed more uniformly in tailings, and the porosity of samples is significantly reduced by layered scanning analysis. The results of triaxial shear tests showed that adding organic matrix sodium citrate effectively increased the cohesion, internal friction angle, and peak stress of the reinforced tailings. It aims to provide a novel idea, a creative approach, and a method to enhance the reinforcement effect of tailings and green solidification technology in the mining environment.

Harmonic and DC Bias Hysteresis Characteristics Simulation Based on an Improved Preisach Model.

Transformers, reactors and other electrical equipment often work under harmonics and DC-bias working conditions. It is necessary to quickly and accurately simulate the hysteresis characteristics of soft magnetic materials under various excitation conditions in order to achieve accurate calculations of core loss and the optimal design of electrical equipment. Based on Preisach hysteresis model, a parameter identification method for asymmetric hysteresis loop simulation is designed and applied to the simulation of hysteresis characteristics under bias conditions of oriented silicon steel sheets. In this paper, the limiting hysteresis loops of oriented silicon steel sheets are obtained through experiments under different working conditions. The first-order reversal curves(FORCs) with asymmetric characteristics is generated numerically, and then the Everett function is established under different DC bias conditions. The hysteresis characteristics of the oriented silicon steel sheets under harmonics and DC bias are simulated by improving FORCs identification method of the Preisach model. By comparing the results of simulation and experiment, the effectiveness of the proposed method is verified, so as to provide an important reference for material production and application.

Associated Factors and Immune Response to the Hepatitis B Vaccine with a Standard Schedule: A Prospective Study of People with HIV in China.

Hepatitis B (HB) vaccination is recommended for people with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). We aimed to assess the immune response to the HB vaccine and associated factors using the standard vaccination schedule among people with HIV (PWH) in China. A prospective study was carried out from 2016 to 2020 in Beijing, China. PWH were given three 20 µg doses of recombinant HB vaccine at 0, 1, and 6 months. Blood samples were taken within 4-6 weeks after each dose to evaluate the anti-HBs levels. A total of 312 participants completed vaccination and serologic testing. The seroconversion (anti-HBs ≥ 10 IU/L) rates following the first, second, and third doses of the vaccine were 35.6% (95% CI: 30.3-40.9%), 55.1% (95% CI: 49.6-60.7%), and 86.5% (95% CI: 82.8-90.3%), respectively, and the geometric means of the anti-HBs titers were 0.8 IU/L (95% CI: 0.5-1.6 IU/L), 15.7 IU/L (95% CI: 9.4-26.3 IU/L), and 241.0 IU/L (95% CI: 170.3-341.1 IU/L), respectively. In multivariate analysis, after three doses of vaccination, age, CD4 cell count, and HIV-RNA viral load were significantly associated with strong, moderate, and weak response, respectively. These findings confirm that these personal health conditions are related to the HB response. HB vaccination in PWH using the standard schedule was still highly effective in the context of early treatment initiation, especially among participants aged 30 years and younger.

Significantly Stabilizing Hydrogen Evolution Reaction Induced by Nb-Doping Pt/Co(OH)2 Nanosheets.

High stability and efficiency of electrocatalysts are crucial for hydrogen evolution reaction (HER) toward water splitting in an alkaline media. Herein, a novel nano-Pt/Nb-doped Co(OH)2 (Pt/NbCo(OH)2 ) nanosheet is designed and synthesized using water-bath treatment and solvothermal reduction approaches. With nano-Pt uniformly anchored onto NbCo(OH)2 nanosheet, the synthesized Pt/NbCo(OH)2 shows outstanding electrocatalytic performances for alkaline HER, achieving a high stability for at least 33 h, a high mass activity of 0.65 mA µg-1 Pt, and a good catalytic activity with a low overpotential of 112 mV at 10 mA cm-2 . Both experimental and theoretical results prove that Nb-doping significantly optimizes the hydrogen adsorption free energy to accelerate the Heyrovsky step for HER, and boosts the adsorption of H2 O, which further enhances the water activation. This study provides a new design methodology for the Nb-doped electrocatalysts in an alkaline HER field by facile and green way.

Bedaquiline and Linezolid improve anti-TB treatment outcome in drug-resistant TB patients with HIV: A systematic review and meta-analysis.

OBJECTIVES: We aimed to assess the effect of second-line anti-TB treatment and determine which drugs can achieve the greatest clinical benefit for DR-TB-HIV patients by comparing multiple chemotherapy regimens, to provide a basis for evidence-based practice. METHODS: We searched three electronic databases (PubMed, Web of Science and Cochrane) for related English studies published since 2010. A random-effect model was used to estimate the pooled result for the treatment outcomes. Subgroup analysis based on possible factors, such as ART, baseline CD4 T-cell count, treatment regimens, and profiles of drug resistance, was also conducted to assess factors for favorable outcome. Outcomes were treatment success and mortality. RESULTS: 38 studies, 40 cohorts with 9279 patients were included. The pooled treatment success, mortality, treatment failure, and default rates were 57.5 % (95 % CI 53.1-61.9), 21 % (95 % CI 17.8-24.6), 4.8 % (95 % CI 3.5-6.5), and 10.7 % (95 % CI 8.7-13.1), respectively, in patients with DR-TB and HIV co-infection. Subgroup analysis showed that BDQ and LZD based regimen, and ≥ 2 Group A drugs were associated with a higher treatment success rate. Besides, higher CD4 T-cell count at baseline was also correlated with higher treatment success rate, too. CONCLUSIONS: Suboptimal anti-TB outcomes underlining the need to expand the application of effective drugs and better regimen in high HIV setting. BDQ and LZD based all-oral regimen and early ART could contribute to higher treatment success, particularly among XDR-TB-HIV patients. Given that all included studies were observational, our findings emphasize the need for high-quality studies to further investigate the optimal treatment regimen for DR-TB-HIV.

Increased Risk of Vitamin D Deficiency Among HIV-Infected Individuals: A Systematic Review and Meta-Analysis.

Background: Human immunodeficiency virus (HIV) infection is a heavy burden worldwide. Observational studies have reported a high prevalence of vitamin D deficiency (VDD) among people living with HIV (PLWH). However, its deficiency is also a global health problem. Therefore, we conducted a meta-analysis and systemic review to compare differences between HIV-infected subjects and non-HIV-infected subjects. Methods: We searched PubMed, Web of Science, Embase, and Cochrane library. We extracted data, including demographic information, study type, vitamin D-related values, and HIV-related values, ultimately including 15 studies after removing duplicates and screening titles, abstracts, and full texts and finally performing a meta-analysis in terms of vitamin D level and vitamin D deficiency prevalence. Results: Regarding VDD prevalence, the HIV vs. the non-HIV group had an odds ratio of 1.502 (95% CI, 1.023-2.205; P = 0.038). In the subgroup analysis, the odds ratios were 1.647 (95% CI, 1.020-2.659; P = 0.041; I 2 = 94.568) from 7 studies (age over 40), 2.120 (95% CI, 1.122-4.008; P = 0.021; I 2 = 0.000) from 2 studies (BMI less than or equal to 25), 1.805 (95% CI, 1.373-2.372; P = 0.042; I 2 = 74.576) from 7 studies (latitude <40), 2.120 (95% CI, 1.122-4.088; P = 0.021; I 2 = 0.000) from 2 studies (only included male participants), and 2.296 (95% CI, 1.287-4.097; P = 0.005; I 2 = 19.927) from 3 studies (only included ART-experienced participants). Thirteen studies were deemed to have moderate quality, while two had high quality. Conclusions: HIV infected subjects are prone to have VDD compared with general population. ART, older age, lower BMI, lower latitude and male sex may present risk factors for VDD in PLWH. Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=228096.

Mortality predictors among patients with HIV-associated pulmonary tuberculosis in Northeast China: A retrospective cohort analysis.

The coexistence of pulmonary tuberculosis (PTB) and human immunodeficiency virus (HIV) infection leads to high morbidity and mortality in these populations. Although antiretroviral therapy (ART) has decreased TB incidence in HIV-infected patients, this coexistence still prevails in China. Patients with HIV-PTB admitted to Beijing You An Hospital from 2014 to 2018 were retrospectively enrolled, and information on demographics, clinical characteristics, and laboratory findings were extracted from medical records. Predictors of death, including age (adjusted hazard ratio [AHR]: 1.03; 95% confidence interval [CI]: 1.00-1.05), tobacco use (AHR: 2.76; 95% CI: 1.54-4.94), history of tuberculosis (AHR: 3.53; 95% CI: 1.82-6.85), not being on ART (AHR: 2.94; 95% CI: 1.31-6.63), extrapulmonary tuberculosis (AHR: 2.391; 95% CI: 1.37-4.18), sputum smear positivity (AHR: 2.84; 95% CI: 1.61-4.99), CD4+ T cell count ≤ 50 cells/µl (AHR: 3.45; 95% CI: 1.95-6.10), and initiating ART ≥ 8 weeks after the initiation of antituberculous therapy (odds ratio: 3.30; 95% CI: 1.09-10.04). By contrast, there were no deaths among the six patients who began ART within 8 weeks after the initiation of antituberculous therapy. Age, tobacco use, not being on ART, extrapulmonary tuberculosis, sputum smear positivity, and CD4+ T cell count ≤50 cells/µl predict those patients at high risk of death among HIV-infected patients with PTB, and the time of initiating ART after the initiation of antituberculous therapy is also important for prognosis.

Immune Response to Hepatitis B Virus Vaccine Among People Living With HIV: A Meta-Analysis.

Background: There is conflicting evidence about whether a double dose of the hepatitis B virus (HBV) vaccine induces better immunity than the standard-dose vaccine for people living with HIV (PLWH). This study provides a meta-analysis that summarizes the efficacy of HBV vaccine regimens among HIV-infected patients, clarifying the role of particular factors such as dose and frequency of vaccination in vaccine responsiveness and highlighting the need for evidence-based practice to assess HBV vaccination among PLWH. Methods: Randomized clinical trials (RCTs) and prospective studies reporting vaccination response rates among PLWH were found through a search of PubMed, Cochrane, and the Web of Science. The key outcome was vaccine response. A random-effects model was used to estimate the pooled response rate. Subgroup analysis was conducted to evaluate key factors and explore sources of heterogeneity. Possible biases were assessed using quality and publication bias assessment. Results: Eligible studies included controlled trials that examined the effects of 17 interventional studies with 1,821 participants. Among PLWH who received the HBV vaccine, the pooled response rate of HBV vaccination was 71.5% (95% CI 64.0%-77.9%, p < 0.001). Compared with the standard dose (65.5%, 95% CI 53.1%-76.1%), the double dose (75.2%, 95% CI 66.2%-82.5%) was associated with a better response rate [Q(1) = 19.617, p < 0.001]. When stratified by schedule, the four-dose schedule (89.7%, 95% CI 83.1%-93.9%) had a higher response rate than the three-dose schedule (63.3%, 95% CI 56.6%-69.4%) and the difference was significant [Q(1) = 88.305, p < 0.001]. PLWH with higher CD4+ T-cell counts (>500 cells/mm3) at the time of vaccination had better response rates [Q(1) = 88.305, p < 0.001]. Conclusions: In this meta-analysis, the double dose of the HBV vaccine and multiple injections were associated with better immune responses than the standard HBV vaccine regimen in PLWH. Higher seroconversion rates were observed in PLWH with high CD4+ T-cell levels, indicating that individuals infected with HIV should receive the HBV vaccine as soon as possible after diagnosis. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/.

Pretreatment lymphocyte-to-monocyte ratios predict AIDS-related diffuse large B-cell lymphoma overall survival.

The lymphocyte-to-monocyte ratio (LMR) and platelet-to-lymphocyte ratio (PLR) have been reported to be useful for predicting the prognosis of various malignancies, including diffuse large B-cell lymphoma (DLBCL). However, little is known about the role of LMR and PLR in the prognosis of DLBCL patients with human immunodeficiency virus (HIV) infection. We retrospectively evaluated the prognostic value of the LMR and PLR in patients with newly diagnosed AIDS-related diffuse large B-cell lymphoma (AR-DLBCL) who were treated with CHOP-like chemotherapy at a single institution. In 33 AR-DLBCL patients, the median follow-up period was 32 months (range: 7-85 months), with an estimated 2-year overall survival (OS) rate of 79.9%. The univariate analysis confirmed the LMR ≤ 2.74 (p = .015), PLR ≥ 337.7 (p = .019), and moderate anemia (p = .045) were associated with inferior survival. The independent significant association between low LMR and poor OS in the multivariate analysis was identified (HR: 0.033, 95% CI: 0.001-0.853, p = .040). However, PLR (p = .459) and moderate anemia (p = .102) did not retain an independent significance in the multivariate analysis. Moreover, compared with the high-LMR group, patients with low-LMR more frequently had B symptoms (p = .010) and lower CD4+T cell count (p < .001). The pretreatment LMR may be an effective prognostic factor for predicting OS in patients with AR-DLBCL.

Nanostructured Ni2SeS on Porous-Carbon Skeletons as Highly Efficient Electrocatalyst for Hydrogen Evolution in Acidic Medium.

Nickel dichalcogenides have received extensive attention as promising noble-metal-free nanocatalysts for a hydrogen evolution reaction. Nonetheless, their catalytic performance is restricted by the sluggish reaction kinetics, limited exposed active sites, and poor conductivity. In this work, we report on an effective strategy to solve those problems by using an as-designed new porous-C/Ni2SeS nanocatalyst with the Ni2SeS nanostubs anchored on with porous-carbon skeletons process. On the basis of three advantages, as the enhancement of the intrinsic activity using the ternary sulfoselenide, increased number of exposed active sites due to the 3D hollow substrate, and increased conductivity caused by porous-carbon skeletons, the resulting porous-C/Ni2SeS requires an overpotential of only 121 mV at a current density of 10 mA cm-2 with a Tafel slope of 78 mV dec-1 for hydrogen evolution in acidic media and a good long-term stability. Density functional theory calculations also show that the Gibbs free energy of hydrogen adsorption of the Ni2SeS was -0.23 eV, which not only is close to the ideal value (0 eV) and Pt reference (-0.09 eV) but also is lower than those of NiS2 and NiSe2; large electrical states exist in the vicinity of the Fermi level, which further improves its electrocatalytic performance. This work provides new insights into the rational design of ternary dichalcogenides and hollow structure materials for practical applications in HER catalysis and energy fields.

Evaluation of SARS-CoV-2 RNA shedding in clinical specimens and clinical characteristics of 10 patients with COVID-19 in Macau.

As a city famous for tourism, the public healthcare system of Macau SAR has been under great pressure during the outbreak of the Coronavirus Disease 2019 (COVID-19). In this study, we report clinical and microbiological features of ten COVID-19 patients enrolled in the Centro Hospitalar Conde de São Januário (CHCSJ) between January 21 to February 16, 2020. Clinical samples from all patients including nasopharyngeal swab (NPS)/sputum, urine, and feces were collected for serial virus RNA testing by standard qRT-PCR assay. In total, seven were imported cases and three were local cases. The median duration from Macau arrival to admission in imported cases was 3 days. Four patients required oxygen therapy but none of them needed machinal ventilation. No fatal cases were noted. The most common symptoms were fever (80%) and diarrhea (80%). In the "Severe" group, there was significantly more elderly patients (p=0.045), higher lactate dehydrogenase levels (p=0.002), and elevated C-Reactive protein levels compared to the "Mild to Moderate" group (p<0.001). There were positive SARS-CoV-2 RNA signals in all patients' NPS and stool specimens but negative in all urine specimens. Based on our data on SARS-CoV-2 RNA shedding in stool and the possibility of a lag in viral detection in NPS specimens, the assessment of both fecal and respiratory specimen is recommended to enhance diagnostic sensitivity, and also to aid discharge decision before the role of viral RNA shedding in stool is clarified.

Interleukin-8 is elevated in severe hand, foot, and mouth disease.

INTRODUCTION: Enterovirus 71 (EV71) infections can cause hand, foot, and mouth disease (HFMD), which is a potentially fatal illness in children. Epidemics of HFMD are seen every year globally and present an increasing threat to public health worldwide. METHODOLOGY: To identify potential severity markers for severe HFMD, laboratory findings and levels of eight serum cytokines in 143 EV71-infected patients in Beijing You'an Hospital were analyzed. Patients were grouped by disease severity: Mild (no severe complications) (n = 59), isolated isolated brainstem encephalitis (BE) (n = 47), isolated pulmonary edema (PE) (n = 12), and BE+PE (n = 25). RESULTS: IL-8 levels peaked at day one after admission and were found to be correlated to disease severity, maximal body temperature, and length of hospital stay. Among all tested cytokines, IL-8 was correlated to only IL-6 (p = 0.010). IL-6 and IL-10 were elevated in most patients (98.6% and 70.6%), but not correlated to disease severity (both p > 0.05). IFNγ was only negatively correlated to mild cases (p = 0.025). CONCLUSIONS: IL-8 was correlated to disease severity of HFMD. IL-6 and IL-10, although elevated in most HFMD patients, were not correlated to disease severity.