A one dimensional (1-D) air gap membrane distillation (AGMD) model for flat sheet type modules has been developed. This model is based on mathematical equations that describe the heat and mass ...transfer mechanisms of a single-stage AGMD process. It can simulate AGMD modules in both co-current and counter-current flow regimes. The theoretical model was validated using AGMD experimental data obtained under different operating conditions and parameters. The predicted water vapor flux was compared to the flux measured at five different feed water temperatures, two different feed water salinities, three different air gap widths and two MD membranes with different average pore sizes. This comparison showed that the model flux predictions are strongly correlated with the experimental data, with model predictions being within +10% of the experimentally determined values. The model was then used to study and analyze the parameters that have significant effect on scaling-up the AGMD process such as the effect of increasing the membrane length, and feed and coolant flow rates. The model was also used to analyze the maximum thermal efficiency of the AGMD process by tracing changes in water production rate and the heat input to the process along the membrane length. This was used to understand the gain in both process production and thermal efficiency for different membrane surface areas and the resultant increases in process capital and water unit cost.
•A 1-D model for flat sheet type AGMD modules has been developed.•The model can simulate both co-current and counter-current flow regimes.•The model predictions are strongly correlated with the experimental data.•Energy requirement and costs were investigated.•Scale-up issues are also discussed in this paper.
Background The efficacy of tonsillectomy in immunoglobulin A nephropathy (IgAN) remains controversial. Our meta-analysis was intended to investigate its efficacy as an adjunct or independent ...treatment. Study Design Meta-analysis of prospective and retrospective studies using PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Setting & Population Patients with IgAN treated with or without tonsillectomy. Selection Criteria for Studies Studies that compared clinical remission or end-stage renal disease (ESRD) in patients with IgAN with or without tonsillectomy. Intervention Tonsillectomy. Outcomes Clinical remission and ESRD. Results 14 studies (1,794 patients) were included and a random-effects model was applied. There were significantly greater odds of clinical remission with tonsillectomy (10 studies, 1,431 patients; pooled OR, 3.40; 95% CI, 2.58-4.48; P < 0.001). Sensitivity analysis to exclude the effects of renin-angiotensin system inhibitors yielded consistent results (6 studies, 671 patients; pooled OR for remission, 2.80; 95% CI, 1.91-4.09; P < 0.001). In subgroup analysis of the remission outcome, tonsillectomy plus steroid pulse therapy was superior to steroid pulse therapy alone (7 studies, 783 patients; pooled OR, 3.15; 95% CI, 1.99-5.01; P < 0.001), and tonsillectomy plus conventional steroid therapy was superior to conventional steroid therapy alone (2 studies, 159 patients; pooled OR, 4.13; 95% CI, 1.23-13.94; P = 0.02). Tonsillectomy was superior to general treatment (3 studies, 187 patients; pooled OR for remission, 2.21; 95% CI, 1.20-4.05; P = 0.01). In addition, tonsillectomy was associated with decreased odds of ESRD (9 studies, 873 patients; pooled OR, 0.25; 95% CI, 0.12-0.52; P < 0.001). 2 sensitivity analyses, one excluding studies with less than 5 years’ follow-up and another excluding the confounding effect of renin-angiotensin system inhibitors, yielded nearly the same reduction in ESRD risk (6 studies, 691 patients; pooled OR, 0.20; 95% CI, 0.11-0.36; P < 0.001; and 6 studies, 547 patients; pooled OR, 0.24; 95% CI, 0.14-0.44; P < 0.001). Limitations Most included studies were retrospective cohort studies; we were unable to adjust uniformly for potential confounding variables. Conclusions As adjunct or independent therapy, tonsillectomy may induce clinical remission and reduce the rates of ESRD in patients with IgAN.
Mutant p53 (mutp53) cancers are surprisingly dependent on their hyperstable mutp53 protein for survival, identifying mutp53 as a potentially significant clinical target. However, exploration of ...effective small molecule therapies targeting mutp53 has barely begun. Mutp53 hyperstabilization, a hallmark of p53 mutation, is cancer cell-specific and due to massive upregulation of the HSP90 chaperone machinery during malignant transformation. We recently showed that stable complex formation between HSP90 and its mutp53 client inhibits E3 ligases MDM2 and CHIP, causing mutp53 stabilization. Histone deacetylase (HDAC) inhibitors (HDACi) are a new class of promising anti-cancer drugs, hyperacetylating histone and non-histone targets. Currently, suberoylanilide hydroxamic acid (SAHA) is the only FDA-approved HDACi. We show that SAHA exhibits preferential cytotoxicity for mutant, rather than wild-type and null p53 human cancer cells. Loss/gain-of-function experiments revealed that although able to exert multiple cellular effects, SAHA's cytotoxicity is caused to a significant degree by its ability to strongly destabilize mutp53 at the level of protein degradation. The underlying mechanism is SAHA's inhibition of HDAC6, an essential positive regulator of HSP90. This releases mutp53 and enables its MDM2- and CHIP-mediated degradation. SAHA also strongly chemosensitizes mutp53 cancer cells for chemotherapy due to its ability to degrade mutp53. This identifies a novel action of SAHA with the prospect of SAHA becoming a centerpiece in mutp53-specific anticancer strategies.
To investigate the prevalence of insomnia in college students and analyze the correlation between insomnia and perceived stress.
A cluster sampling method was used to investigate the prevalence of ...insomnia and stress levels in 3702 college students using Insomnia Severity Index (ISI) and Perceived Stress Scale-10 (PSS-10).
Insomnia was detected in 31.4% of the college students, and the symptoms were more severe in male students (
=2.047,
=0.041) and in those with poorer family economic conditions (
=20.423,
<0.001). Insomnia was positively correlated with perceived stress, perceived distress, and perceived coping ability, with correlation coefficients of 0.42, 0.38, and 0.31, respectively (
<0.001). The students with higher levels of perceived stress had higher insomnia scores (
=203.03,
<0.001) and higher detection rate of insomnia (χ
=359.784,
<0.001), and those with moderate or severe insomnia also had higher levels of perceived stress (
=293.569,
<0.001). The types of perceived stress among college studen
Aim
To evaluate the comparative effects of sodium‐glucose co‐transporter 2 (SGLT2) inhibitors on risk of bone fracture in patients with type 2 diabetes mellitus (T2DM).
Methods
PubMed, EMBASE, ...CENTRAL and ClinicalTrials.gov were systematically searched from inception to 27 January 2016 to identify randomized controlled trials (RCTs) reporting the outcome of fracture in patients with T2DM treated with SGLT2 inhibitors. Pairwise and network meta‐analyses, as well as a cumulative meta‐analysis, were performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs).
Results
A total of 38 eligible RCTs (10 canagliflozin, 15 dapagliflozin and 13 empagliflozin) involving 30 384 patients, with follow‐ups ranging from 24 to 160 weeks, were included. The fracture event rates were 1.59% in the SGLT2 inhibitor groups and 1.56% in the control groups. The incidence of fracture events was similar among these three SGLT2 inhibitor groups. Compared with placebo, canagliflozin (OR 1.15; 95% CI 0.71‐1.88), dapagliflozin (OR 0.68; 95% CI 0.37‐1.25) and empagliflozin (OR 0.93; 95% CI 0.74‐1.18) were not significantly associated with an increased risk of fracture. Our cumulative meta‐analysis indicated the robustness of the null findings with regard to SGLT2 inhibitors.
Conclusions
Our meta‐analysis based on available RCT data does not support the harmful effect of SGLT2 inhibitors on fractures, although future safety monitoring from RCTs and real‐world data with detailed information on bone health is warranted.
Cracking is a major concern in the long-term performance of landfill clay liners. Cracking of clay liners is affected by the roots of the vegetation planted to control erosion. While vegetation roots ...may restrict cracking they may introduce preferential flow through the liners. The impact of vegetation roots on the hydraulic properties of clay liners remains unclear. This study investigates the effect of vegetation roots on crack formation and preferential flow through clay liners. Three experimental soil columns were used to observe crack formation by exposure to the weather and to measure the flow through them caused by artificial rainfall. The clay in each column was compacted to 90% relative compaction. The first column was not vegetated and no crack developed in it. The second column was vegetated and underwent drying–wetting cycles outdoor. The third column did not have vegetation but underwent drying–wetting cycles outdoor. Cracks developed in the second and third columns due to the exposure to the weather. Image analysis in the experimental soil columns revealed that vegetation roots restricted crack formation, especially in the early stages of drying–wetting cycles. Infiltration tests performed on the experimental soil columns showed that the unsaturated hydraulic conductivity of the vegetated soil in the second column was respectively about two orders and one order of magnitude larger than those of the soils in the first and third columns. The experimental results imply that the effect of vegetation roots on the preferential flow through landfill clay liners should be considered in practical designs.
•Vegetation roots can restrict the crack development, especially in the early stages.•The saturated hydraulic conductivity of vegetated soil increases 3 orders of magnitude.•The unsaturated hydraulic conductivity of vegetated soil is 2 orders of magnitude larger.•The vegetation roots are significant preferential flow pathways.
To realize online multiaxial fatigue damage assessment for the mechanical components in service, an online multiaxial cycle counting method is proposed coupled with the segment processing technique ...and Wang‐Brow's relative equivalent strain concept. Meanwhile, considering all the stress and strain components, which contribute to the fatigue damage on the critical plane, a multiaxial fatigue damage model without any weight coefficients is also proposed in an equivalent form of shear strain energy. Then, an online fatigue damage evaluation method for multiaxial random loading is developed by combining with the proposed damage model and online cycle counting method. The experimental results showed that the proposed online cycle counting method can be successfully applied to the calculation of multiaxial fatigue damage under random loading. Moreover, the proposed online multiaxial fatigue damage evaluation method can provide satisfactory predictions.
Severe fever with thrombocytopenia syndrome (SFTS) is a newly discovered emerging infectious disease that has recently become epidemic in Asia. The causative agent of SFTS is a novel phlebovirus in ...the family Bunyaviridae, designated SFTS virus (SFTSV). SFTS clinically presents with high fever, thrombocytopenia, leukocytopenia, gastrointestinal disorders, and multi-organ dysfunction, with a high viral load and a high case-fatality rate. In human infection, SFTSV targets microphages, replicates in the spleen of infected mice, and causes thrombocytopenia and a cytokine storm. The tick disseminates virus to humans and animals, forming a special transmission model in nature. Person-to-person transmission though direct contact with patient blood has been frequently reported. Measurements of viral RNA and antibodies have been established for diagnosis, but vaccines and specific therapeutics are not available so far.
Cigarette smoke is a representative source of toxic chemical exposures to humans, and the adverse consequences of cigarette smoking are mediated by its effect on both neuronal and immune–inflammatory ...systems. Cigarette smoking also is a major risk factor for intestinal disorders, such as Crohn’s disease and peptic ulcer. On the other hand, cigarette smoking is protective against developing ulcerative colitis. The effects of cigarette smoking on intestinal disorders include changes in intestinal irrigation and microbiome, increases in permeability of the mucosa, and impaired mucosal immune responses. However, the underlying mechanism linking cigarette smoking with intestinal microbiota dysbiosis is largely unknown. In this communication, we first review the current knowledge about the mechanistic interaction between cigarette smoke and intestinal microbiota dysbiosis, which include the likely actions of nicotine, aldehydes, polycyclic aromatic hydrocarbons, heavy metals, volatile organic compounds and toxic gases, and then reveal the potential mechanisms of the lung–gut cross talk and skin-gut cross talk in regulating the balance of intestinal microbiota and the interrelation of intestinal microbiota dysbiosis and systemic disorders.
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