Search

We aimed to investigate the fluid–solid–ice coupling mechanism as structures break through ice into water. Using LS–DYNA finite element software, a numerical simulation method is established, based on the ALE flow–solid coupling method, and the penalty function contact algorithm, which describes the structure–ice–water coupling interaction. The Eulerian algorithm is used to describe the air and water domains, while the Lagrange method is applied to the wedge and ice structure. The mechanical properties of ice are characterized using the elastic–plastic failure strain model. The feasibility of simulating the entry of structures into water via the ALE method is demonstrated by comparing the experimental and simulation results of wedges entering into water. The applicability of the ice material model in simulating collision–induced breakup is verified by comparing a simulation of a rigid plate hitting a spherical head of ice, with results from the ISO standard. The effects of water during icebreaking are assessed by simulating a wedge breaking through ice into water, as well as through ice without water. Additionally, the ice breakup and motion response of the wedge under different working conditions are compared by varying the wedge mass and icebreaking speed.

Objectives: We conducted a retrospective cohort study of medical records from a large, Maryland, U.S.-based cohort of pediatric primary care patients for potential associations between antibacterial, antifungal and antiviral prescriptions and subsequent suicidal thoughts and/or behaviors. Methods: Using first suicide-related diagnosis as the outcome and prior prescription of antibacterial, antifungal, and/or antiviral use as the exposure, we employed a series of multivariate Cox proportional hazards models. These models examined the hazard of developing newly recognized suicidal thoughts and/or behaviors, controlling for age, sex, race, insurance, number of encounters during the study period, prior mood disorder diagnosis and number of chronic health conditions. We constructed the same series of models stratified by the groups with and without a prior recorded mental or behavioral health diagnosis (MBHD). Results: Suicidal thoughts and/or behaviors were associated with the previous prescription of an antibacterial, antifungal and/or antiviral medication (HR 1.31, 95 %‐CI 1.05–1.64) as well as the total number of such medications prescribed (HR 1.04, 95 %‐CI 1.01–1.08), with the strongest relationship among patients with three or more medications (HR 1.44, 95 %‐CI 1.06–1.96). Among individual medications, the strongest association was with antibacterial medication (HR 1.28, 95 %‐CI 1.03–1.60). Correlations were strongest among the subgroup of patients with no previous (MBHD). Interpretation: Infections treated with antimicrobial medications were associated with increased risks of a suicide-related diagnosis among patients who had not had a previous mental or behavioral health diagnosis. This group should be considered for increased levels of vigilance as well as interventions directed at suicide screening and prevention. Funding: National Institutes of Health, Stanley Medical Research Institute.

ObjectiveChlamydia trachomatis (CT) infection is one of the most common sexually transmitted infections (STIs) worldwide. This study aimed to provide prevalence and associated factors data among patients seeking clinic-based STI services for estimating the disease burden of CT.Study design and methodA cross-sectional survey was conducted among patients attending clinics for STI services. Patients' social-demographic and behavioral information was collected and CT infection was determined by nucleic acid amplification test (NAAT) with self-collected urine specimens. Associated factors were identified using logistic regression.ResultsAmong the 8,324 participants, the overall prevalence was 9.0% with 10.7% for males and 8.3% for females respectively. Multivariate analysis showed that aged < 24 [adjusted odds ratio (aOR) = 1.27, 95% confidence interval (CI) = 1.01–1.59], being unmarried (aOR = 1.64, 95%CI = 1.35–2.00), having junior high school or below education level (aOR = 1.47, 95%CI = 1.13–1.91), having no access to health insurance (aOR = 1.27, 95%CI = 1.07–1.51), and being positive for Neisseria gonorrhoeae (NG, aOR = 4.49, 95%CI = 3.25–6.21) were significantly associated with CT infection.ConclusionWe found that CT infection is prevalent among patients seeking clinic-based STI services in Southern China. Targeted interventions could be implemented for patients with a higher risk of CT infection including those aged < 24, being unmarried, having junior high school or below education level, having no access to health insurance, and being positive for NG. In addition, routine CT screening could be considered a public health strategy by the government.

Abstract The notion that local heritage can be defined by the ‘collective memory’ of a city may be considered as being simplistic nowadays. Heritage is increasingly recognised as knowledge, a cultural product or even a political resource set within specific social circumstances. The local heritage underpins various ways of relating our past with our present and future, which are often much more complicated than we can imagine. The evolution of the conservation of Shanghai’s modern heritage architecture shows this complexity. By tracing more than 50 years’ progress in historic preservation, this paper shows how historical buildings from Shanghai’s early modern period were selected as urban heritage in the changing socio-political contexts of different time periods. Starting with how the first modern buildings were listed in a new Chinese narrative in the 1950s, this paper focuses on the great ideological changes and progress Shanghai achieved after China’s reform and opening policy since the 1980s. Emphasising the great significance of the establishment of local legislation for historic preservation as an extension of the national system, examples of the great enrichment of Shanghai’s local heritage are presented through multiple narratives and interpretations of Shanghai’s modern history. In a deeper observation of various practices and complicated contradictions, the historic preservation of Shanghai’s modern heritage architecture is shown to be a process of continuing to reconstruct the relationships between city and the State, the city and the world, as well as the city’s past, present and future in a pluralist society.

Radiotherapy is a common treatment for abdominal and pelvic tumors, while the radiation-induced intestinal injury (RIII) is one of the major side-effects of radiotherapy, which reduces the life quality and impedes the treatment completion of cancer patients. Previous studies have demonstrated that environmental pollutant microplastics led to various kinds of injury in the gut, but its effects on RIII are still uncovered. In this study, we fed the C57BL/6J mice with distilled water or 50 μg/d polystyrene microplastics (PSMPs) for 17 days and exposed the mice to total abdominal irradiation (TAI) at day 14. Then the severity of RIII was examined by performing histopathological analysis and microbial community analysis. The results demonstrated that PSMPs significantly aggravated RIII in small intestine rather than colon of mice upon TAI. PSMPs increased levels of the histopathological damage and the microbial community disturbance in mice small intestine, shown by the overabundance of Akkermansiaceae and the decrease of microflora including Lactobacillaceae, Muribaculaceae and Bifidobacteriaceae. In conclusion, our results suggested that more microplastics exposure might led to more severe RIII, which should be considered in patients’ daily diet adjustment and clinical radiotherapy plan evaluation. Furthermore, this study also called for the further researches to uncover the underlying mechanism and develop novel strategies to attenuate RIII in mice intestine.

The development of high-performance air filter has become more and more important to public health. However, it has always been very challenging for developing a multifunctional air filter to simultaneously achieve excellent filtration and antibacterial properties. Herein, a versatile air filter was prepared with loading the reduced graphene (rGO) and zinc oxide on the superfine glass fibre (s-GF) with the three-dimensional network structure by in situ sol–gel process followed by calcination, which aims to achieve synergistic high-efficiency air filtration and rapid response to photocatalytic antibacterial properties under visible light. The air filter showed a three-dimensional network structure based on a rGO/ZnO/s-GF multilayer and exhibited the highest catalytic performance by achieving a 95% degradation effect on rhodamine B within 2 h and achieving 100% antibacterial inactivation of the Escherichia coli and Staphylococcus aureus within 4 h under visible light when the weight ratio of rGO in rGO/ZnO is 1.6%. The air filtration efficiency can also be maintained at 99% after loading ZnO and rGO photocatalytic particles. The spectrum of the photoluminescence (PL), UV-Vis diffuse reflectance spectra (DRS) and electron spin resonance (ESR) indicate that the combination of rGO and ZnO on the s-GF can increase the separation of photogenerated carriers and the specific surface area of the air filter, thereby increasing the photocatalytic response and antibacterial properties of the s-GF air filter under visible light in a short time.

Dopaminergic neurons in the substantia nigra pars compacta (SNpc) are characterized by the expression of genes required for dopamine synthesis, handling and reuptake and the expression of these genes is largely controlled by nuclear receptor related 1 (Nurr1). Nurr1 is also expressed in astrocytes and microglia where it functions to mitigate the release of proinflammatory cytokines and neurotoxic factors. Given that Parkinson's disease (PD) pathogenesis has been linked to both loss of Nurr1 expression in the SNpc and inflammation, increasing levels of Nurr1 maybe a promising therapeutic strategy. In this study a novel Nurr1 agonist, SA00025, was tested for both its efficiency to induce the transcription of dopaminergic target genes in vivo and prevent dopaminergic neuron degeneration in an inflammation exacerbated 6-OHDA-lesion model of PD. SA00025 (30mg/kg p.o.) entered the brain and modulated the expression of the dopaminergic phenotype genes TH, VMAT, DAT, AADC and the GDNF receptor gene c-Ret in the SN of naive rats. Daily gavage treatment with SA00025 (30mg/kg) for 32 days also induced partial neuroprotection of dopaminergic neurons and fibers in rats administered a priming injection of polyinosinic-polycytidylic acid (poly(I:C) and subsequent injection of 6-OHDA. The neuroprotective effects of SA00025 in this dopamine neuron degeneration model were associated with changes in microglial morphology indicative of a resting state and a decrease in microglial specific IBA-1 staining intensity in the SNpc. Astrocyte specific GFAP staining intensity and IL-6 levels were also reduced. We conclude that Nurr1 agonist treatment causes neuroprotective and anti-inflammatory effects in an inflammation exacerbated 6-OHDA lesion model of PD.