A sublinear oscillation theorem

AbstractAn oscillation criterion is given for the second order nonlinear differential equation y″ + a(t)ƒ(y) = 0, where a(t) is continuous but is not assumed to be non-negative for all large values of t and ƒ(y) is non-decreasing in y and satisfies yƒ(y) > 0 for y ≠ 0. This result generalizes a recent extension of Belohorec's theorem due to Kwong and Wong and also incorporates an earlier result of Coles

Oscillation Criteria for Second Order Nonlinear Differential Equations Involving General Means

AbstractConsider the second order nonlinear differential equation (E) y″+a(t)f(y)=0 where a(t)∈C[0,∞), f(y)∈C1(−∞,∞), f′(y)≥0, and yf(y)>0 for y≠0. Furthermore, f(y) also satisfies either a superlinear or a sublinear condition, which covers the nonlinear function f(y)=y|y|γ−1 with γ>1 and 0<γ<1, respectively, commonly known as the Emden–Fowler case. Here the coefficient function a(t) is allowed to be negative for arbitrarily large values of t. Kamenev type oscillation criteria involving integral averages for the linear equations (L) y″+a(t)y=0 are extended to the nonlinear equation (E) by using more general means. The results extend similar results on general means by Philos for the linear equation (L) and also results based upon Kamenev's integral averaging method concerning the nonlinear equation (E)

Correlates of physical activity level among hemodialysis patients in Selangor, Malaysia.

INTRODUCTION: There is mounting evidence demonstrating the importance of adequate physical activity to promote better well-being among hemodialysis patients. Available data pertaining to the levels of physical activity and its determinants among hemodialysis patients is, however, scarce in Malaysia. The objectives of this study are hence to determine the levels of physical activity and it associated factors among hemodialysis patients. METHODOLOGY: A total of 70 subjects were recruited from three dialysis centres in Selangor. A face-to-face interview was conducted to obtain socio-demographic data and subjects' knowledge on dietary sources. Medical history, biochemical parameters and weight status were obtained from medical records. Physical activity level (PAL) was assessed using the Global Physical Activity Questionnaire (GPAQ). RESULTS: A total of 81.4% and 18.6% of the respondents had low and moderate PALs, respectively. Thus, none of the respondents had high PAL. Serum creatinine, education level, personal income and knowledge score on potassium-related medical complications were factors found to correlate significantly with PAL. Multiple linear regression analysis showed that higher PAL was predicted by a lower knowledge score on dietary sodium source, higher education and higher serum creatinine. CONCLUSION: Despite consistent documentation of the potential positive impact of physical exercise on hemodialysis outcomes, the level of physical activity remains low among these patients. It is hoped that these findings can add to the existing body of knowledge and serve as a supporting document for the formulation of appropriate interventions to improve the status of physical activity among hemodialysis patients in Malaysia

Storytelling as a pedagogical strategy for culturally responsive mathematics teaching

This paper reports an intervention study with 60 Primary three students in Hong Kong mathematics classrooms in which the language of instruction (English) was not the first language for neither the teachers nor their students. The purpose of this study is to investigate the effectiveness of storytelling to develop fraction language and concepts based on the theory of culturally responsive teaching. The pre-test scores of the intervention group was significantly lower than the control group, yet post-test scores showed that both groups performed comparably well. These initial findings suggested that integrating storytelling with a culturally responsive teaching approach can reduce the achievement gap between culturally and linguistically diverse students in rural settings and their peers in urban districts

Bronchiolitis Obliterans Organising Pneumonia (BOOP) in a lung cancer patient after lobectomy

A 79 year-old patient with lung cancer underwent a standard thoracotomy and lobectomy. Postoperatively, he developed low-grade fever and dyspnoea. Chest X-rays showed progressive lung infiltrates, which was subsequently diagnosed to be Bronchiolitis Obliterans Organizing Pneumonia (BOOP) by transbronchial lung biopsy. He responded well to corticosteroid therapy. The case report is followed by a brief discussion on BOOP in association with lung cancer and thoracotomy

Trends and burden of diabetes in pregnancy among Aboriginal and non-Aboriginal mothers in Western Australia, 1998–2015

Background Diabetes in pregnancy (DIP), which includes pre-gestational and gestational diabetes, is more prevalent among Aboriginal women. DIP and its adverse neonatal outcomes are associated with diabetes and cardiovascular disease in the offspring. This study investigated the impact of DIP on trends of large for gestational age (LGA) in Aboriginal and non-Aboriginal populations, and added to the limited evidence on temporal trends of DIP burden in these populations. Methods We conducted a retrospective cohort study that included all births in Western Australia between 1998 and 2015 using linked population health datasets. Time trends of age-standardised and crude rates of pre-gestational and gestational diabetes were estimated in Aboriginal and non-Aboriginal mothers. Mixed-effects multivariable logistic regression was used to estimate the association between DIP and population LGA trends over time. Results Over the study period, there were 526,319 births in Western Australia, of which 6.4% were to Aboriginal mothers. The age-standardised annual rates of pre-gestational diabetes among Aboriginal mothers rose from 4.3% in 1998 to 5.4% in 2015 and remained below 1% in non-Aboriginal women. The comparable rates for gestational diabetes increased from 6.7 to 11.5% over the study period in Aboriginal women, and from 3.5 to 10.2% among non-Aboriginal mothers. LGA rates in Aboriginal babies remained high with inconsistent and no improvement in pregnancies complicated by gestational diabetes and pre-gestational diabetes, respectively. Regression analyses showed that DIP explained a large part of the increasing LGA rates over time in Aboriginal babies. Conclusions There has been a substantial increase in the burden of pre-gestational diabetes (Aboriginal women) and gestational diabetes (Aboriginal and non-Aboriginal) in recent decades. DIP appears to substantially contribute to increasing trends in LGA among Aboriginal babies

Optimized exosome isolation protocol for cell culture supernatant and human plasma.

Extracellular vesicles represent a rich source of novel biomarkers in the diagnosis and prognosis of disease. However, there is currently limited information elucidating the most efficient methods for obtaining high yields of pure exosomes, a subset of extracellular vesicles, from cell culture supernatant and complex biological fluids such as plasma. To this end, we comprehensively characterize a variety of exosome isolation protocols for their efficiency, yield and purity of isolated exosomes. Repeated ultracentrifugation steps can reduce the quality of exosome preparations leading to lower exosome yield. We show that concentration of cell culture conditioned media using ultrafiltration devices results in increased vesicle isolation when compared to traditional ultracentrifugation protocols. However, our data on using conditioned media isolated from the Non-Small-Cell Lung Cancer (NSCLC) SK-MES-1 cell line demonstrates that the choice of concentrating device can greatly impact the yield of isolated exosomes. We find that centrifuge-based concentrating methods are more appropriate than pressure-driven concentrating devices and allow the rapid isolation of exosomes from both NSCLC cell culture conditioned media and complex biological fluids. In fact to date, no protocol detailing exosome isolation utilizing current commercial methods from both cells and patient samples has been described. Utilizing tunable resistive pulse sensing and protein analysis, we provide a comparative analysis of 4 exosome isolation techniques, indicating their efficacy and preparation purity. Our results demonstrate that current precipitation protocols for the isolation of exosomes from cell culture conditioned media and plasma provide the least pure preparations of exosomes, whereas size exclusion isolation is comparable to density gradient purification of exosomes. We have identified current shortcomings in common extracellular vesicle isolation methods and provide a potential standardized method that is effective, reproducible and can be utilized for various starting materials. We believe this method will have extensive application in the growing field of extracellular vesicle research

The effects of mindfulness-based stress reduction program on the mental health of family caregivers: a randomized controlled trial

&lt;b&gt;Background&lt;/b&gt; Caregivers of people with chronic conditions are more likely than non-caregivers to have depression and emotional problems. Few studies have examined the effectiveness of mindfulness-based stress reduction (MBSR) in improving their mental well-being. &lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods&lt;/b&gt; Caregivers of persons with chronic conditions who scored 7 or above in the Caregiver Strain Index were randomly assigned to the 8-week MBSR group (n = 70) or the self-help control group (n = 71). Validated instruments were used to assess the changes in depressive and anxiety symptoms, quality of life, self-efficacy, self-compassion and mindfulness. Assessments were conducted at baseline, post-intervention and at the 3-month follow-up. &lt;p&gt;&lt;/p&gt; &lt;b&gt;Results &lt;/b&gt;Compared to the participants in the control group, participants in the MBSR group had a significantly greater decrease in depressive symptoms at post-intervention and at 3 months post-intervention (p &lt; 0.01). The improvement in state anxiety symptoms was significantly greater among participants in the MBSR group than those of the control group at post-intervention (p = 0.007), although this difference was not statistically significant at 3 months post-intervention (p = 0.084). There was also a statistically significant larger increase in self-efficacy (controlling negative thoughts; p = 0.041) and mindfulness (p = 0.001) among participants in the MBSR group at the 3-month follow-up compared to the participants in the control group. No statistically significant group effects (MBSR vs. control) were found in perceived stress, quality of life or self-compassion. &lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions &lt;/b&gt;MBSR appears to be a feasible and acceptable intervention to improve mental health among family caregivers with significant care burden, although further studies that include an active control group are needed to make the findings more conclusive

DNA hybridization catalysts and catalyst circuits

Practically all of life's molecular processes, from chemical synthesis to replication, involve enzymes that carry out their functions through the catalysis of metastable fuels into waste products. Catalytic control of reaction rates will prove to be as useful and ubiquitous in DNA nanotechnology as it is in biology. Here we present experimental results on the control of the decay rates of a metastable DNA "fuel". We show that the fuel complex can be induced to decay with a rate about 1600 times faster than it would decay spontaneously. The original DNA hybridization catalyst [15] achieved a maximal speed-up of roughly 30. The fuel complex discussed here can therefore serve as the basic ingredient for an improved DNA hybridization catalyst. As an example application for DNA hybridization catalysts, we propose a method for implementing arbitrary digital logic circuits

Glassy Phase Transition and Stability in Black Holes

Black hole thermodynamics, confined to the semi-classical regime, cannot address the thermodynamic stability of a black hole in flat space. Here we show that inclusion of correction beyond the semi-classical approximation makes a black hole thermodynamically stable. This stability is reached through a phase transition. By using Ehrenfest's scheme we further prove that this is a glassy phase transition with a Prigogine-Defay ratio close to 3. This value is well placed within the desired bound (2 to 5) for a glassy phase transition. Thus our analysis indicates a very close connection between the phase transition phenomena of a black hole and glass forming systems. Finally, we discuss the robustness of our results by considering different normalisations for the correction term.Comment: v3, minor changes over v2, references added, LaTeX-2e, 18 pages, 3 ps figures, to appear in Eour. Phys. Jour.