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Cold regions are particularly vulnerable to climate change. Thus, evaluating the response of water quality evolution to climate change in cold regions is vital for formulating adaptive countermeasures for pollution control under changing climatic conditions. Taking the Songhua River Basin (SRB) in Northeast China as the target area, we designed a water–heat–nitrogen coupled model based on the principle of water and energy transfer and nitrogen cycle processes model (WEP-N) in cold regions. The impact of climate change on pollution load and water quality was analyzed during the freezing, thawing, and non-freeze–thaw periods by taking the sudden change point (1998) of precipitation and runoff evolution in the SRB as the cut-off. The ammonia nitrogen load at Jiamusi station, the outlet control station in the SRB, was decreased by 1502.9 t in the change period (1999–2018) over the base period (1956–1998), with a − 9.2% decrease due to climate change. Compared to the ammonia nitrogen load during the base period, the ammonia nitrogen load decreased by − 171.3, − 506.9, and − 824.8 t during the freezing, thawing, and non-freeze–thaw periods, respectively, while the coefficient of variation showed an increasing trend during three periods, especially during the freezing and thawing periods. However, the water quality changes differed among periods owing to varying runoff during the year. Meanwhile, increasing runoff and decreasing ammonia nitrogen load improved water quality at Jiamusi station during the freezing period. During the thawing and non-freeze–thaw period, the water quality deteriorated due to the decrease in runoff more than the decrease in ammonia nitrogen load. Hence, the impact of climate change on water quality during thawing and non-freeze–thaw periods should be monitored to potentially offset the human influence on pollution control. The difference in the rate of change of the proportion of Class IV water between the two models with or without the soil freeze–thaw mechanism was 15.9%. The result shows that the application of a model that does not consider the freeze–thaw mechanism might slightly exaggerate the impact of climate change on water quality. [ABSTRACT FROM AUTHOR]

The nitrogen cycle in cold regions during the freeze–thaw period is complex. Although previous studies have investigated the phenomenon of nitrogen transport and transformation, the underlying mechanisms are vague. Existing models have limitations in terms of loose coupling or weak physical mechanisms. Therefore, a new distributed nonpoint source pollution model, the water and energy transfer processes and nitrogen cycle processes model in cold regions, was developed in this study, with closely coupled water, heat, and nitrogen processes at the watershed scale. The model considered the driving effects of pressure, gravity, solute, and temperature potentials on water and nitrogen movement in soil and the transformation relationship among nitrogen forms. Physical evaluation and simulations were conducted for the Heidingzi River Watershed during two freeze–thaw periods: 2017–2018 and 2018–2019. The soil temperature absolute error was < 0.82 ℃. The relative errors in stratified liquid water, soil nitrogen content, river flow rate, and river nitrogen concentration were mostly < 10%. Nitrogen transport with water had an obvious "upward agglomeration effect" during the freezing period and a "concentrated release effect" during the thawing period, which was attributed to changes in soil water potential as the freezing front moved down. Disregarding the effects of solute potential and temperature potential will result in an underestimate of the outflow of pollutants during the thawing period. The model can be applied to reveal water quality deterioration in cold regions during thawing. [ABSTRACT FROM AUTHOR]

Introduction: Current guidelines recommend amphotericin B as the preferred drug for induction therapy; however, amphotericin B is not available in certain settings. Induction therapy with amphotericin B deoxycholate or voriconazole has been shown to be an effective treatment for talaromycosis. However, prospective clinical trials comparing these two antifungal drugs are absent from the literature. Methods: In this open-labeled, multicenter, prospective controlled trial, we enrolled patients at 15 hospitals in China from 2019 to 2020. Participants received induction treatment with either amphotericin B deoxycholate intravenously at a dose of 0.5 to 0.7 mg per kilogram per day or voriconazole at a dose of 6 mg/kg intravenously twice daily for the first day, followed by 4 mg/kg intravenously twice daily for 3 days, and then voriconazole was given either intravenously (4 mg/kg intravenously twice daily) or orally (200 mg twice daily) for the remaining 10 days. The primary outcome was all-cause mortality during 48 weeks after baseline. Secondary outcomes were mortality at week 2 or week 24, clinical resolution of talaromycosis, and fungal clearance at week 2. A propensity score (PS) matching analysis was performed to control confounding factors. Results: We observed no difference in the risk of death at week 2, at week 24, or at week 48 in either the unmatched cohort or the matched cohort. Both in the unmatched and the matched cohorts, logistic regression analysis revealed a significantly lower odds ratio of clinical resolution (OR 0.450, 95% CI 0.291–0.696, p < 0.001; OR 0.443, 95% CI 0.261–0.752, p = 0.003) and fungal clearance (OR 0.514, 95% CI 0.333–0.793, p = 0.003; OR 0.542, 95% CI 0.318–0.923, p = 0.024) in voriconazole users compared to amphotericin B deoxycholate users over the course of 2 weeks. In the induction therapy without ART subgroup patients in the amphotericin B deoxycholate group showed a significantly higher rate of clinical resolution and fungal clearance than those in the voriconazole group (56.1% vs. 30.4%, 95% CI 13.4–36.5, p = 0.000; 63.8% vs. 40.4%, 95% CI 11.1–34.7, p = 0.000), whereas there was no significant difference in clinical resolution and fungal clearance in the induction therapy combined with ART subgroup. Conclusions: Induction therapy using voriconazole had a similar efficacy, in terms of all-cause mortality rate, to induction therapy using amphotericin B deoxycholate in HIV-infected patients with talaromycosis over a 48-week observation period. Amphotericin B deoxycholate contributed to earlier fungal clearance and earlier clinical resolution of symptoms in the induction therapy without ART subgroup, whereas amphotericin B deoxycholate use did not contribute to a significant difference in clinical resolution and fungal clearance in the induction therapy combination with ART subgroup. Trial Registration: ChiCTR1900021195. Registered 1 February 2019, http://www.chictr.org.cn/showproj.aspx?proj=35362. [ABSTRACT FROM AUTHOR]

Background: Intramural pregnancy is an uncommon type of ectopic pregnancy, where the gestational sac is completely encircled by myometrium and unconnected with endometrial cavity, fallopian tubes or round ligament. Owing to its potentially life-threatening hemorrhage and uterine rupture, early diagnosis and management are urgently required. We present a case of a woman undergoing zigzag medical procedures, which featured non-consensus preoperative diagnosis of intramural and interstitial pregnancy and an intramural ectopic pregnancy ultimately confirmed and successfully removed by emergency laparoscopy. Additionally, we present a review of the related literature and discuss its varied clinical features, imageological characters, diagnosis, differential diagnosis and multiple treatments.Methods: A comprehensive bibliographic search through PubMed, using keywords: intramural ectopic pregnancy. Relevant literatures published from January 2013 to April 2019 were reviewed.Results: Twenty-four cases in total for intramural ectopic pregnancy including this report were reviewed. Diagnoses were mainly made by ultrasound images. Most patients had a history of uterine surgery or intrauterine operation and had been surgically resected. None of the mothers were in danger, but only one case had live birth at 37 weeks of gestation.Conclusion: Non-specific clinical presentation and non-uniform ultrasound criteria pose a challenge for us to make timely and accurate management. Integrated radiological examinations and communication and cooperation between sonographers and gynecologists play a vital role in diagnostic accuracy and selecting the optimal therapeutic method of an intramural pregnancy. [ABSTRACT FROM AUTHOR]

The in situ TiSi/Ti inoculants were successfully prepared by vacuum arc-melting and melt-spinning method. An efficient route by adding a small quantity of TiSi/Ti inoculants to Ti melt has been first proposed to modify the coarse grains of as cast microstructure of pure titanium in this paper. It was found that the microstructure of ribbon inoculants was cellular structure that composed of TiSi and α-Ti phases. The grain refining effect of the inoculants was significantly improved with the adding ratio range from 0.2% to 0.5% in weight. With the increase of addition amount of inoculants on Ti melt, the tensile strength, yield strength and microhardness of pure titanium are significantly improved except elongation. The excellent grain refining effect can be attributed to the heterogeneous nucleation of the titanium grain on the precipitated TiSi phases in the Si-rich regions and the constitutional supercooling of Si in the Si-poverty regions. It is suggested that the in situ Ti5Si3/Ti inoculants is a promising inoculants for titanium alloys. [ABSTRACT FROM AUTHOR]

The substantial burden of cancer and diabetes and the association between the two conditions has been a motivation for researchers to look for targeted strategies that can simultaneously affect both diseases and reduce their overlapping burden. In the absence of randomized clinical trials, researchers have taken advantage of the availability and richness of administrative databases and electronic medical records to investigate the effects of drugs on cancer risk among diabetic individuals. The majority of these studies suggest that metformin could potentially reduce cancer risk. However, the validity of this purported reduction in cancer risk is limited by several methodological flaws either in the study design or in the analysis. Whether metformin use decreases cancer risk relies heavily on the availability of valid data sources with complete information on confounders, accurate assessment of drug use, appropriate study design, and robust analytical techniques. The majority of the observational studies assessing the association between metformin and cancer risk suffer from methodological shortcomings and efforts to address these issues have been incomplete. Future investigations on the association between metformin and cancer risk should clearly address the methodological issues due to confounding by indication, prevalent user bias, and time-related biases. Although the proposed strategies do not guarantee a bias-free estimate for the association between metformin and cancer, they will reduce synthesis of and reporting of erroneous results. [ABSTRACT FROM AUTHOR]