Coupling behavior between adhesive and abrasive wear mechanism of aero-hydraulic spool valves

AbstractLeakage due to wear is one of the main failure modes of aero-hydraulic spool valves. This paper established a practical coupling wear model for aero-hydraulic spool valves based on dynamic system modelling theory. Firstly, the experiment for wear mechanism verification proved that adhesive wear and abrasive wear did coexist during the working process of spool valves. Secondly coupling behavior of each wear mechanism was characterized by analyzing actual time-variation of model parameters during wear evolution process. Meanwhile, Archard model and three-body abrasive wear model were utilized for adhesive wear and abrasive wear, respectively. Furthermore, their coupling wear model was established by calculating the actual wear volume. Finally, from the result of formal test, all the required parameters for our model were obtained. The relative error between model prediction and data of pre-test was also presented to verify the accuracy of model, which demonstrated that our model was useful for providing accurate prediction of spool valve’s wear life

5-Nitro-2-(3-phenylpropylamino) Benzoic Acid Inhibits the Proliferation and Migration of Lens Epithelial Cells by Blocking CaMKII Signaling

Posterior capsule opacification (PCO) is a post-surgery complication of cataract surgery, and lens epithelial cells (LECs) are involved in its development. A suppressive effect on LECs is exerted by the non specific chloride channel inhibitor 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) exerts. Herein, the growth and migration inhibitory effects of NPPB on LECs were assessed, and the mechanism underlying the effects were investigated by focusing on Ca2+/CaMKII signaling. LECs were treated with different concentrations of NPPB, and the changes in cell viability, cell-cycle distribution, anchorage-dependent growth, migration, Ca2+ level, and CaMKII expression were evaluated. NPPB inhibited LECs’ proliferation and induced G1 cell-cycle arrest in the cells. Regarding LECs’ mobility, NPPB suppressed the cells’ anchorage-dependent growth ability and inhibited their migration. Changes in cell phenotypes were associated with an increased intracellular Ca2+ level and down-regulation of CaMKII. Together these results confirmed the inhibitory effect of NPPB on the proliferation and migration of LECs, and the effect was shown to be associated with the induced level of Ca2+ and the inhibition of CaMKII signaling transduction

Risk of Recurrent Falls after Indoor and Outdoor Falls in the Elderly

Background: Falls are the most common and serious health problems of the elderly. The primary goal of the study is to determine whether risk for recurrent indoor and outdoor falls differ by type of previous falls and by gender. Method: We analyzed data on falls collected in the MOBILIZE Boston prospective cohort study of community-dwelling women and men aged 65 years or older. The participants were followed for up to 4.3 years (median=2.3y). Logistic regression models, clustered by participant, were performed to estimate the probability of a subsequent indoor or outdoor fall after any fall, indoor fall, and outdoor fall. Natural log transformed time since the most recent any fall, time since the most recent indoor fall, and time since the most recent outdoor fall were used to predict probabilities of a subsequent fall of each type. Result: Among 502 participants who reported at least one fall during the follow-up, 330 had at least one reccurent fall during the follow-up period. Men and women differed in their tendencies to fall recurrently as well as in their response to an outdoor fall. Median time to the recurrent any fall since the most recent any fall was 9 weeks (IQR=22) for men and 17 weeks (IQR=30) for women [p= Conclusion: Falls, especially outdoor falls, may have different implications for the subsequent fall risks of men vs. women. Further study should examine whether outdoor falls may be an indicator of robustness for elderly women but for frailty in elderly men

Proteome characterization of cassava (Manihot esculenta Crantz) somatic embryos, plantlets and tuberous roots

<p>Abstract</p> <p>Background</p> <p>Proteomics is increasingly becoming an important tool for the study of many different aspects of plant functions, such as investigating the molecular processes underlying in plant physiology, development, differentiation and their interaction with the environments. To investigate the cassava (<it>Manihot esculenta </it>Crantz) proteome, we extracted proteins from somatic embryos, plantlets and tuberous roots of cultivar SC8 and separated them by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).</p> <p>Results</p> <p>Analysis by liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS) yielded a total of 383 proteins including isoforms, classified into 14 functional groups. The majority of these were carbohydrate and energy metabolism associated proteins (27.2%), followed by those involved in protein biosynthesis (14.4%). Subsequent analysis has revealed that 54, 59, 74 and 102 identified proteins are unique to the somatic embryos, shoots, adventitious roots and tuberous roots, respectively. Some of these proteins may serve as signatures for the physiological and developmental stages of somatic embryos, shoots, adventitious roots and tuberous root. Western blotting results have shown high expression levels of Rubisco in shoots and its absence in the somatic embryos. In addition, high-level expression of α-tubulin was found in tuberous roots, and a low-level one in somatic embryos. This extensive study effectively provides a huge data set of dynamic protein-related information to better understand the molecular basis underlying cassava growth, development, and physiological functions.</p> <p>Conclusion</p> <p>This work paves the way towards a comprehensive, system-wide analysis of the cassava. Integration with transcriptomics, metabolomics and other large scale "-omics" data with systems biology approaches can open new avenues towards engineering cassava to enhance yields, improve nutritional value and overcome the problem of post-harvest physiological deterioration.</p

Creating Store and Community-Level Feedback Reports for Food Establishments to Support Nutrition Environment Improvement

INTRODUCTION. The availability of healthy options in food stores is important to healthy eating and obesity prevention. The Health Statistics and Geography Lab at UMass Medical School is conducting longitudinal surveys to determine the availability of healthy food in food stores throughout the state of Massachusetts as part the Community Transformation Grant and Mass in Motion initiatives. Providing feedback to store proprietors and managers as well as community workers is an important component to support community environmental interventions. METHODS. The Community Nutrition Environment Evaluation Data System (C-NEEDS) was developed for food environment surveillance. C-NEEDS takes into account seasonal and geographic variations in food supplies, cultural relevance, and USDA dietary recommendations. Since May 2012, nearly 1300 food stores throughout Massachusetts have been surveyed and analyzed. Healthy Food Availability Index (HFAI) is calculated for each store (range: 0 to 56), with a higher score indicating greater availability of healthy items. REPORTS. Store-level reports are provided to proprietors and managers of individual food stores in conjunction with community workers. The reports provide HFAI scores for the store for the current year, previous year(s), if available, comparing to the average scores of similar stores within the same community. Community workers and proprietors of food stores can use the store-level reports to determine areas of need and appropriate intervention methodology. Community-level feedback reports provide information on average scores, by store type, for their community as well as for communities of similar size and socio-demographic status. They can be used to compare community HFAI to comparable communities as well as track change in scores over time. DISCUSSION. Providing feedback to community workers and food store owners is an essential aspect of community enviornment interventions. The information contained in the C-NEEDS feedback reports provides benchmarks for both store owners and communities to achieve

Impact of hypertension and smoking on the rupture of intracranial aneurysms and their joint effect

Background In general population, the prevalence of intracranial aneurysm reaches as high as three percent. The goal of the study was to analyze retrospectively the independent risk factors for the rupture of intracranial aneurysms and their joint effect. Methods The records and angiographies of continuous 519 intracranial aneurysm patients treated at our center between February 2013 and July 2014 were retrospectively analyzed. Ruptured group and unruptured group were included in the study according to their clinical and imaging information. Univariate analysis and multivariate logistic regression analysis was used to identified independent risk factors for the rupture of intracranial aneurysms. We assessed the joint effect of independent risk factors for the rupture of intracranial aneurysms with an additional logistic regression analysis. Results The results of multivariate analysis show that hypertension (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.05–2.18) and smoking (odds ratio [OR], 1.57; 95% confidence interval [CI], 1.06–2.33) were independent risk factors for rupture of intracranial aneurysms. The joint risk of hypertension and smoking was higher (OR, 2.28; 95% CI, 1.29–4.02) than the risks of hypertension (OR, 1.74; 95% CI, 1.11–2.72) and smoking (OR, 1.86; 95% CI, 1.05–3.29) independently. Conclusions Hypertension and smoking increase of the rupture risk of intracranial aneurysms. And the joint risk of hypertension and smoking was higher than the risks of hypertension and smoking independently

Stent-assisted coiling of very small wide-necked intracranial aneurysms: Complications, anatomical results and clinical outcomes

Background and objective Treatment of very small (≤3mm) wide-necked intracranial aneurysms remains controversial, we investigated the efficacy and safety of stent-assisted coiling of such aneurysms. Methods From September 2008 to December 2012, 112 very small wide-necked intracranial aneurysms in 108 patients were embolized with stent-assisted coiling. We assessed the initial neurological conditions, complications and anatomic results. The follow-up results were evaluated with DSA and mRS. Results Stent deployment was successful in 104 of 108 procedures (96.3%). 11 complications (10.2%) occurred during procedures, including 5 events of aneurysm rupture, 3 events of thromboembolism. The rate of complication, rupture and thromboembolism was not statistically different between the ruptured and unruptured patients (P=0.452, P=0.369, P=1.000, respectively). The initial aneurysmal occlusion was Raymond scale (RS) 1 in 34 patients (31.5%), RS2 in 53 patients (49.1%), and RS3 in 21 patients (19.4%). 79 aneurysms were available for anatomic follow-up of 12–47 months, stable occlusion in 45 aneurysms (57.0%), progressive complete occlusion in 34 aneurysms (43.0%). 95 patients(88.0%) were available for a clinical follow-up of 12–52 months, 92 patients (96.8%) had favorable clinical outcomes (mRS ≤2), 3 patients (3.2%) had morbidity (mRS: 3–5). The morbidity was not statistically different between the ruptured and unruptured patients (P=1.000). Conclusions Stent-assisted coiling of very small wide-necked intracranial aneurysms may be effective and safe. Because of low risk of rupture in such aneurysms, the coiling of unruptured such aneurysms must be selective. The long-term efficacy and safety of coiling such aneurysms remains to be determined in larger prospective series