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Purpose To understand the service performance of full ceramic ball bearings under extreme working conditions and improve their service life, dynamic characteristic tests of full ceramic ball bearings under ultra-low temperature conditions were carried out by a low-temperature bearing life testing machine, and temperature rise and friction were measured under extreme low-temperature environment. Design/methodology/approach The heat-flow coupling model of bearing was established by CFD software, and the test results were further analyzed. Findings The results show that the temperature rise of the bearing is not obvious in the liquid nitrogen environment. With the increase of the chamber temperature, the lubrication state of the bearing changes, resulting in the temperature rise of the outer ring of the bearing. As the temperature of the test chamber increases, the friction force on the bearing increases first and then decreases under the action of multifactor coupling. Research limitations/implications The research results provide test data and theoretical basis for the application of all-ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions. Practical implications The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions. Social implications The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions. Originality/value The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

Introduction: Time to endovascular treatment (EVT) is a major determinant of patient outcomes for large vessel occlusion (LVO) strokes. Delays in interfacility transfers, however, can limit treatment efficacy. The Cincinnati Stroke Triage Assessment Tool (C-STAT) is a pre-hospital screen used to identify patients suspected of having LVOs. In October 2019, the “Oahu LVO Bypass Protocol” was adopted island-wide for all EMS evaluations. In this protocol, patients with C-STAT+ scores bypassed the nearest local hospital and were diverted to a Comprehensive Stroke Center (CSC). Our study aims to identify how this protocol has impacted onset-to-reperfusion times for patients with LVOs. Methods: A retrospective chart review was performed on all patients receiving EVT from January 1 st , 2017 to February 1 st , 2022. Patients were dichotomized into pre and post bypass groups using October 1 st , 2019 as the implementation date. All non-EMS transfers, posterior circulation strokes, and patients >8 hours from symptom onset were excluded from analysis. We compared the two time epochs using descriptive statistics and an interrupted time-series analysis (ITS). Results: During the 5-year study period, 520 patients received EVT at our institution with an average age of 70.6 and median NIHSS of 19. A total of 115 patients met inclusion for the pre-bypass cohort and 172 patients for the post-bypass cohort. Significant reductions were observed in the median times (pre-bypass(min) [IQR] vs. post-bypass(min) [IQR]) from onset-to-CSC arrival (140[65-214] vs. 68[46-157], p Conclusion: Implementation of the Oahu LVO bypass protocol shows significant reduction in onset-to-reperfusion times without delays to tPA administration, while also reducing rates of interfacility transfers.

Marxism has been extensively interpreted by theoreticians, revolutionaries and practitioners of the world socialist movement from its origins in the mid-nineteenth century to its demise as an ideol...

Background In bowel obstruction and biliary pancreatitis, patients receive more expedient surgical care when admitted to surgical compared with medical services. This has not been studied in acute cholecystitis. Methods Retrospective analysis of clinical and cost data from July 2013 to September 2015 for patients with cholecystitis who underwent laparoscopic cholecystectomy in a tertiary care inpatient hospital. One hundred ninety lower-risk (Charlson-Deyo) patients were included. We assessed admitting service, length of stay (LOS), time from admission to surgery, time from surgery to discharge, number of imaging studies, and total cost. Results Patients admitted to surgical (n = 106) versus medical (n = 84) service had shorter mean LOS (1.4 days vs. 2.6 days), shorter time from admission to surgery (0.4 days vs. 0.8 days), and shorter time from surgery to discharge (0.8 days vs. 1.1 days). Surgical service patients had fewer CT (38% vs. 56%) and magnetic resonance imaging (MRI) (5% vs. 16%) studies. Cholangiography (30% vs. 25%) and endoscopic retrograde cholangiopancreatography (ERCP) (3 vs. 8%) rates were similar. Surgical service patients had 39% lower median total costs (US $7787 vs. US $12572). Conclusion Nonsurgical admissions of patients with cholecystitis are common, even among lower-risk patients. Routine admission to the surgical service should decrease LOS, resource utilization and costs. Level of evidence Therapeutic/care management, level IV.

Retention index under the programmed temperature gas chromatography (PTGC) conditions (IT) is widely accepted despite of its unsatisfactory reproducibility. Effects of heating rate (rT), stationary liquid film thickness (df), inlet pressure (pi), initial temperature (To) and polarity of stationary phase (sp) on IT reproducibility were studied in the present work. We found that excellent reproducibility and regularity of IT values are obtainable at conditions of relatively low To and relatively high rT and pi, as well as use of quality thick-film column under an operation in a single-retention behavior region (i.e., cubic equation model region). Most solutes were eluted in the dual-retention behavior region under the commonly used conditions described in the literature (i.e., relatively high To and relatively low rT for thin-film columns). The IT reproducibility under the optimum condition was approximately 37 times better than that under the commonly used conditions. The present work further validated the concept about dual- and single-retention behaviors of solutes in PTGC and proposed a principle to improve IT reproducibility.

Monocytes play a vital role in HIV-associated neurocognitive disorder (HAND), postulated to transport HIV into the brain and secrete pro-inflammatory cytokines. We analyzed cytokines released by cultured peripheral blood mononuclear cells enriched with the CD14 marker isolated from HIV-infected individuals with HAND and normal cognition (NC) in combination antiretroviral therapy naive and after 1 year on treatment. Interleukin-8 and monocyte chemoattractant protein-1 levels were higher in HAND compared with NC at baseline (P = 0.002 and P < 0.0001). These cytokines remained higher in HAND patients 1 year after combination antiretroviral therapy and were significant when NC patients who were initially HAND were excluded (P = 0.012 and P = 0.002). Both correlated with baseline CD14 peripheral blood mononuclear cell HIV DNA levels supporting the role of HIV DNA reservoir size and monocyte cytokines in HAND persistence.

The temporal trend of hospitalizations, cost, and outcomes associated with preeclampsia with severe features have been inadequately studied. The publicly available Healthcare Cost and Utilization Project (HCUP) National Inpatient Sample (NIS) database was accessed to examine the temporal trend of total number of discharges, age, death, and mean charges per admission associated with preeclampsia with severe features. Eleven-year temporal trends (2004 to 2014) of these measures were compared using linear regression and run charts using the statistical process control rule. From 2004 to 2014, the total number of discharges related to preeclampsia with severe features increased both for Hawai‘i and the U.S. (United States) (Hawai‘i: 104 to 231; U.S.: 35,082 to 55,235; both P

BACKGROUND Chronic liver disease and cirrhosis is the 12th leading cause of death in the United States. Patients with decompensated-cirrhosis, especially with hepatic encephalopathy/coma (HC), have a higher rate of early readmission and contribute to higher healthcare cost. AIM To evaluate the national inpatient trends of discharges, mortalities and financial impacts associated with four common conditions of cirrhosis. METHODS The publicly available Healthcare Cost and Utilization Project National Inpatient Sample database was utilized to examine the temporal trends of total number of discharges, mortalities and inpatient costs related to hospitalization with a primary diagnosis of HC, transjugular intrahepatic portosystemic shunt (TIPS), esophageal varices with bleeding (EV) and spontaneous bacterial peritonitis (SBP) from 2005 to 2014. The ten-year temporal trends were assessed using simple linear regressions and multiple regression analysis. Two-sided P < 0.05 was considered statistically significant. RESULTS From 2005 to 2014, the total number of discharges with cirrhosis-associated complications trended up for HC, SBP and EV (HC by 70% increase, P < 0.0001; SBP by 819% increase, P = 0.0002; EV by 9% increase, P = 0.016), but not for TIPS (P = 0.90). HC related to viral hepatitis showed faster increase by 357% (P < 0.0001) in comparison to HC not related to viral hepatitis by 33 % (P = 0.0006). Overall, in-hospital mortality rates for each condition decreased from 2005 to 2014 (HC by 29% reduction, P = 0.0024; SBP by 26% reduction, P = 0.0038; TIPS by 32% reduction, P = 0.021) except for EV (P = 0.34). After adjustment for inflation, aggregate cost of hospitalization for EV, HC, and SBP significantly increased by 20%, 86%, and 980%, respectively, from 2005 to 2014 (all P < 0.02), while TIPS had trend toward decreasing cost by 3% (P = 0.95). CONCLUSION The number of hospitalizations and costs for some of the cirrhosis-associated conditions increased. However, the inpatient mortality rates for most of these conditions decreased.

The current theory of programmed temperature gas chromatography considers that solutes are focused by the stationary phase at the column head completely and does not explicitly recognize the different effects of initial temperature (To ) and heating rate (rT ) on the retention time or temperature of a homologue series. In the present study, n-alkanes, 1-alkenes, 1-alkyl alcohols, alkyl benzenes, and fatty acid methyl esters standards were used as model chemicals and were separated on two nonpolar columns, one moderately polar column and one polar column. Effects of To and rT on the retention of nonstationary phase focusing solutes can be explicitly described with isothermal and cubic equation models, respectively. When the solutes were in the stationary phase focusing status, the single-retention behavior of solutes was observed. It is simple, dependent upon rT only and can be well described by the cubic equation model that was visualized through four sequential slope analyses. These observed dual- and single-retention behaviors of solutes were validated by various experimental data, physical properties, and computational simulation.

HIV DNA in monocytes has been linked to HIV-associated neurocognitive disorders (HAND), however, characterization of monocyte subsets associated with HAND remains unclear. We completed a prospective study of antiretroviral therapy-naïve, HIV-infected Thais, with varying degrees of cognitive impairment, compared to HIV-uninfected controls. Monocyte subsets' CCR2, CCR5 and CD163 expression were profiled and inflammatory markers in plasma and cerebrospinal fluid (CSF), measured. Lower numbers of CCR2(+)non-classical monocytes were associated with worse neuropsychological test performance (r=0.43, p=0.024). CCR2(+)non-classical monocyte count inversely correlated with CSF neopterin (r=-0.43, p=0.035) and plasma TNF-α levels (r=-0.40, p=0.041). These data benchmark CCR2(+)non-classical monocytes as an independent index of cognitive impairment.

First, simply expounded the purpose and meaning of detecting tungsten extracted from prefi lable syringes: And then, designed simulation experiment for extracting tungsten from prefi lable glass syringes. and established determination methods of tungsten content by ICP-MSL Finaly, evaluated the limit of content of tungsten ?extracting from simulation experiment.

Understanding the impacts of the built environment on physical activity (PA) is essential to promoting children’s PA. The purpose of this study was to investigate the effects of schoolyard renovations and a PA recess curriculum alone and in combination on children’s PA. This was a 2 (learning landscape [LL] vs. non-LL) × 2 (curriculum intervention vs. no curriculum intervention) factorial design with random assignment to the curriculum intervention, and six elementary schools per condition. PA outcomes were assessed preprogram, mid-program, immediate postprogram, and one year postprogram. No meaningful intervention effects were found. Lack of an effect may be due to the brief dose of recess, the curriculum not being integrated within the schoolyard, the LL implementation occurring prior to the study, or the already high levels of PA. Potential avenues to promote PA include making recess longer, integrating recess into the school curricula, and developing recess PA curricula integrating schoolyards.

Statistical principles and methods are critical to the success of biomedical and translational research. However, it is difficult to track and evaluate the monetary value of a biostatistician to a medical school (SoM). Limited published data on this topic are available, especially comparing across SoMs. Using National Institutes of Health (NIH) awards and American Association of Medical Colleges (AAMC) faculty counts data (2010–2013), together with online information on biostatistics faculty from 119 institutions across the country, we demonstrated that the number of biostatistics faculty was significantly positively associated with the amount of NIH awards, both as a school total and on a per faculty basis, across various sizes of U.S. SoMs. Biostatisticians, as a profession, should be proactive in communicating and advocating the value of their work and their unique contribution to the long-term success of a biomedical research enterprise. Supplementary materials for this article are available online.

HIV-associated neurocognitive disorders (HAND) continues to be prevalent (30–50 %) despite plasma HIVRNA suppression with combination antiretroviral therapy (cART). There is no proven therapy for individuals on suppressive cARTwith HAND. We have shown that the degree of HIV reservoir burden (HIV DNA) in monocytes appear to be linked to cognitive outcomes. HIV infection of monocytes may therefore be critical in the pathogenesis of HAND. A single arm, open-labeled trial was conducted to examine the effect of maraviroc (MVC) intensification on monocyte inflammation and neuropsychological (NP) performance in 15 HIV subjects on stable 6-month cART with undetectable plasma HIV RNA (10 copies/106 cells). MVC was added to their existing cART regimen for 24 weeks. Post-intensification change in monocytes was assessed using multiparametric flow cytometry, monocyte HIV DNA content by PCR, soluble CD163 (sCD163) by an ELISA, and NP performance over 24 weeks. In 12 evaluable subjects, MVC intensification resulted in a decreased proportion of circulating intermediate (median; 3.06 % (1.93, 6.45) to 1.05 % (0.77, 2.26)) and nonclassical (5.2 % (3.8, 7.9) to 3.2 % (1.8, 4.8)) CD16-expressing monocytes, a reduction in monocyte HIV DNA content to zero log10 copies/106 cells and in levels of sCD163 of 43 % by 24 weeks. This was associated with significant improvement in NP performance among six subjects who entered the study with evidence of mild to moderate cognitive impairment. The results of this study suggest that antiretroviral therapy with potency against monocytes may have efficacy against HAND.

OBJECTIVE: We sought to achieve 100% compliance with all 3 Children’s Asthma Care (CAC; CAC-1, CAC-2, CAC-3) measures and track attendance at follow-up appointments with the patient-centered medical home. The impact of these measures on readmission and emergency department utilization rates was evaluated. METHODS: This quality improvement study evaluated compliance with CAC measures in pediatric patients aged 2 to 18 years old hospitalized with a primary diagnosis of asthma from January 1, 2008, through June 30, 2012. A multidisciplinary Asthma Task Force was assembled to develop interventions. Attendance at the follow-up appointment was tracked monthly from January 1, 2009. Readmission and emergency department utilization rates were compared between the preimplementation period (January 1, 2006, through December 31, 2007) and the postimplementation period (January 1, 2008, through June 30, 2012). RESULTS: The preimplementation period included 231 subjects and the postimplementation period included 532 subjects. Compliance with CAC-3 was 95% from October 1, 2009, through June 30, 2012. Compliance with the postdischarge follow-up appointment was 69% from January 1, 2009 through September 30, 2009, increasing significantly to 90% from October 1, 2009, through June 30, 2012 (P < .001). Postimplementation readmission rates significantly decreased in the 91- to 180-day postdischarge interval (odds ratio: 0.29; 95% confidence interval: 0.11–0.78). CONCLUSIONS: In children hospitalized with asthma, compliance with the asthma core measures and the postdischarge follow-up appointment with the primary care provider was associated with reduced readmission rates at 91 to 180 days after discharge. We attribute our results to a comprehensive set of interventions designed by our multidisciplinary Asthma Task Force.

In this article, we prove that a finite solvable group with character degree graph containing at least four vertices has Fitting height at most 4 if each derived subgraph of four vertices has total degree not more than 8. We also prove that if the vertex set ρ(G) of the character degree graph Δ(G) of a solvable group G is a disjoint union ρ(G) = π1 ∪ π2, where |πi| ≥ 2 and pi, qi∈ πi for i = 1,2, and no vertex in π1 is adjacent in Δ(G) to any vertex in π2 except for p1p2 and q1q2, then the Fitting height of G is at most 4.

Dehydrins (DHNs) are late embryonic abundant proteins characterized by the dehydrin domains that are involved in plant abiotic stress tolerance. In this study, fifty-four wheat DHN unigenes were identified in the expressed sequence tags database. These genes encode seven types of dehydrins (KS, SK3, YSK2, Y2SK2, Kn, Y2SK3, and YSK3) and separate in 32 homologous clusters. The gene amplification differed among the dehydrin types, and members of the YSK2- and Kn-type DHNs are more numerous in wheat than in other cereals. The relative expression of all of these DHN clusters was analyzed using an in silico method in seven tissue types (i.e. normal growing shoots, roots, and reproductive tissues; developing and germinating seeds; drought- and cold-stressed shoots) as well as semi-quantitative reverse transcription polymerase chain reaction in seedling leaves and roots treated by dehydration, cold, and salt, respectively. The role of the ABA pathway in wheat DHN expression regulation was analyzed. Transcripts of certain types of DHNs accumulated specifically according to tissue type and treatment, which suggests their differentiated roles in wheat abiotic stress tolerance.

Native Hawaiians/Pacific Islanders experience a high prevalence of overweight/obesity. The Diabetes Prevention Program Lifestyle Intervention (DPP-LI) was translated into a 3-month community-based intervention to benefit these populations. The weight loss and other clinical and behavioral outcomes of the translated DPP-LI and the socio-demographic, behavioral, and biological factors associated with the weight loss were examined. A total of 239 Native Hawaiian/Pacific Islander adults completed the translated DPP-LI through four community-based organizations (CBOs). Changes from pre- to post-intervention assessments in weight, blood pressure, physical functioning, exercise frequency, and fat in diet were measured. Significant improvements on all variables were found, with differences observed across the four CBOs. CBOs with predominately Native Hawaiian and ethnically homogenous intervention groups had greater weight loss. General linear modeling indicated that larger baseline weight and CBO predicted weight loss. The translated DPP-LI can be effective for Native Hawaiians/Pacific Islanders, especially when socio-cultural, socio-economic, and CBO-related contextual factors are taken into account.

Linear mixed-effects model has been widely used in longitudinal data analyses. In practice, the fitting algorithm can fail to converge due to boundary issues of the estimated random-effects covariance matrix G, i.e., being near-singular, non-positive definite, or both. Current available algorithms are not computationally optimal because the condition number of matrix G is unnecessarily increased when the random-effects correlation estimate is not zero. We propose an adaptive fitting (AF) algorithm using an optimal linear transformation of the random-effects design matrix. It is a data-driven adaptive procedure, aiming at reducing subsequent random-effects correlation estimates down to zero in the optimal transformed estimation space. Simulations show that AF significantly improves the convergent properties, especially under small sample size, relative large noise and high correlation settings. One real data for Insulin-like Growth Factor (IGF) protein is used to illustrate the application of this algorithm implemented with software package R (nlme).

Magnetic resonance (MR) cystography or MR-based virtual cystoscopy is a promising new technology to evaluate the entire bladder in a fully non-invasive manner. It requires the anatomical bladder images be acquired at high spatial resolution and with adequate signal-to-noise ratio (SNR). This often leads to a long-time scan (> 5 minutes) and results in image artifacts due to involuntary bladder motion and deformation. In this paper, we investigated an image-processing approach to mitigate the problem of motion and deformation. Instead of a traditional single long-time scan, six repeated short-time scans (each of approximately 1 minute) were acquired for the purpose of shifting bladder motion from intra-scan into inter-scans. Then the inter-scan motions were addressed by registering the short-time scans to a selected reference and finally forming a single average motion-corrected image. To evaluate the presented approach, three types of images were generated: (1) the motion-corrected image by registration and average of the short-time scans; (2) the directly-averaged image of the short-time scans (without motion correction); and (3) the single image of the corresponding long-time scan. Six experts were asked to blindly score these images in terms of two important aspects: (i) the definition of the bladder wall and (ii) the overall expression on the image quality. Statistical analysis on the scores suggested that the best result in both the aspects is achieved by the presented motion-corrected average. Furthermore the superiority of the motion-corrected average over the other two is statistically significant by the measure of a linear mixed-effect model with p-values

The current theory of programmed temperature gas chromatography considers that solutes are focused by the stationary phase at the column head completely and does not explicitly recognize the different effects of initial temperature (To ) and heating rate (rT ) on the retention time or temperature of a homologue series. In the present study, n-alkanes, 1-alkenes, 1-alkyl alcohols, alkyl benzenes, and fatty acid methyl esters standards were used as model chemicals and were separated on two nonpolar columns, one moderately polar column and one polar column. Effects of To and rT on the retention of nonstationary phase focusing solutes can be explicitly described with isothermal and cubic equation models, respectively. When the solutes were in the stationary phase focusing status, the single-retention behavior of solutes was observed. It is simple, dependent upon rT only and can be well described by the cubic equation model that was visualized through four sequential slope analyses. These observed dual- and single-retention behaviors of solutes were validated by various experimental data, physical properties, and computational simulation.

BackgroundInflammation may contribute to cardiovascular disease (CVD) among antiretrovirally suppressed HIV-infected individuals. We assessed relationships of monocyte, CD8 T-cell activation and plasma biomarkers to changes in carotid artery intima-media thickness (CIMT).MethodsLongitudinal study of HIV-infected subjects ≥40years and on stable antiretroviral therapy (ART) ≥3months. Peripheral blood mononuclear cells were immunophenotyped by multiparameteric flow cytometry to quantify classical (CD14(++)CD16(-)), intermediate (CD14(++)CD16(+)), non-classical (CD14(low/+)CD16(++)) and transitional (CD14(+)CD16(-)) monocyte subsets and activated (CD38(+)HLA-DR(+)) CD8(+) T-cells at baseline. Plasma biomarkers were assessed by multiplex Luminex assay. High-resolution B-mode ultrasounds of right carotid arteries were obtained. Changes in CIMT over two years at the right common carotid artery (CIMTCCA) and right bifurcation (CIMTBIF) were outcome variables.ResultsWe studied 50 subjects: 84% male, median age 49 (Q1, Q3; 46, 56) years, median CD4 count 461 (317, 578) cells/mm(3), and with HIV RNA≤50 copies/mL in 84%. Change in CIMTBIF correlated with log values of baseline absolute count of non-classical monocytes (r=0.37, p=0.020), and with MCP-1 (r=0.42, p=0.0024) and TNF-α (r=0.30, p=0.036) levels. In multivariable linear regression, only non-classical monocytes and MCP-1 predicted the change in CIMTBIF, independent of Framingham Risk Score and baseline CIMTBIF. No correlation was noted between CD8 T-cell activation and CIMTBIF change. Monocyte subsets, CD8 T-cell activation, and biomarker concentrations were not correlated with changes in CIMTCCA.ConclusionsOur findings highlight the role of non-classical monocytes and MCP-1 in the progression of CIMTBIF in HIV-infected individuals on stable ART independent of traditional cardio-metabolic risk factors.

This paper proposed a full band up-mixer implemented in 0.18μm COMS process for UWB wireless systems. The linearity, noise figure and other performance are improved by using current bleeding technique and inserting a LC network on common source nodes of the switches stage. The inductance peaking technique is adopted to flatten conversion gain over the 14 sub-bands of UWB system. The up-converting mixer converts an input of 264MHz intermediate frequency to an output of 3.1---10.6GHz radio frequency signal. From the post simulation results, the proposed up-mixer achieves conversion gain of 10±1dB and the IIP3 of 7.19dBm and power consumption of 2.4mW at 1.2V power supply.