1,381 research outputs found
Prediction of open-hole tensile strength of unidirectional flax yarn reinforced polypropylene composite by analytical and numerical models
Open-hole tensile strength of unidirectional flax yarn reinforced polypropylene composites has been predicted fordifferent laminates with varying lay-up through analytical and numerical models. Point stress criterion (PSC), modified PSCand finite element modeling (FEM) have been applied to examine the effect of different open-hole sizes on the stressbearing capacity. The characteristic length (d0) of the composites has been confirmed by PSC which depends on thespecimen geometry. The modified PSC has been used with stress concentration factor, notch sensitivity factor, andexponential parameter for evaluating the open-hole tensile strength. The stress distribution and the open-hole tensile strengthhave also been obtained by finite element simulation. The best correlations between the experimental and predicted resultshave been achieved from modified PSC model than with traditional PSC and FEM models
Nutraceutical Composition of Ber (Zizyphus mauritiana Lamk.) Juice: Effect of Enzyme-Assisted Processing
An investigation was undertaken to study the effect of pre-press maceration treatment with cell-wall degrading enzyme, pectinase, on antioxidant composition of ber juice, during 2011-2012. Enzyme-assisted processing significantly (p<0.05) improved antioxidant composition of ber juice. Ber juice extracted using pectinase had richer nutraceutical composition than in the Control. There was an overall increase of 43% in juice yield, 30% in total phenolics and 37% in total flavonoids with use of pectinase. In vitro total antioxidant activity (AOX) in ber juice was 19.58μmol Trolox/ml in Ferric Reducing Antioxidant Power (FRAP) and 13.44μmol Trolox/ml in Cupric Reducing Antioxidant Capacity (CUPRAC) assay. There was 41-65% increase in total AOX of ber juice extracted with the enzyme overstraight pressed juice. Results indicated that tailoring of the enzyme can yield antioxidant-rich juice products
Solaris photometric survey: Search for circumbinary companions using eclipse timing variations
Eclipse timing variations (ETV) have been a successful tool for detecting
circumbinary companions to eclipsing binaries (EB). While TESS and Kepler have
been prolific for ETV searches, they sometimes can be limited by time and sky
coverage which can be addressed by specialised ground-based ETV surveys. We
present the initial results from the Solaris photometric survey which uses four
0.5m robotic telescopes in the southern hemisphere to look for circumbinary
companions. We present the method of light curve extraction, detrending, and EB
modelling using the observations from the Solaris network. Using these light
curves we extract precise eclipse timing for 7 EB and look for companions using
a Lomb-Scargle periodogram search. We find two possible periodic signals for
the target GSC 08814-01026. With the system having strong activity, we check
for the feasibility of orbital solutions at these two periods. We find that the
245 +/- 1 d period is due to an M-dwarf mass companion. This makes GSC
08814-01026 a candidate compact hierarchical triple system. The other periodic
signal at 146 +/- 1 d is an artefact of stellar activity.Comment: 14 pages, 9 figures, Accepted for publication in MNRAS. This is a
pre-copyedited, author-produced PDF of an article accepted for publication in
MNRAS following peer revie
Paracetamol for osteoarthritis; is there a need for revision of guidelines?
Paracetamol (PCT) is the most commonly prescribed drug for pain of osteoarthritis (OA). Its advantage over non-steroidal anti-inflammatory drugs (NSAIDs) in terms of better gastrointestinal and renal safety had made this choice obvious especially in the elderly; a few years ago. Considering the current treatment guidelines (American College of Rheumatology, National Institute for Health and Care Excellence and European League against Rheumatism) which uphold PCT as the first choice drug for OA, a few studies have questioned the aforesaid advantage of PCT against its modest efficacy in patients with OA
Phoretic Motion of Spheroidal Particles Due To Self-Generated Solute Gradients
We study theoretically the phoretic motion of a spheroidal particle, which
generates solute gradients in the surrounding unbounded solvent via chemical
reactions active on its surface in a cap-like region centered at one of the
poles of the particle. We derive, within the constraints of the mapping to
classical diffusio-phoresis, an analytical expression for the phoretic velocity
of such an object. This allows us to analyze in detail the dependence of the
velocity on the aspect ratio of the polar and the equatorial diameters of the
particle and on the fraction of the particle surface contributing to the
chemical reaction. The particular cases of a sphere and of an approximation for
a needle-like particle, which are the most common shapes employed in
experimental realizations of such self-propelled objects, are obtained from the
general solution in the limits that the aspect ratio approaches one or becomes
very large, respectively.Comment: 18 pages, 5 figures, to appear in European Physical Journal
Leptin in non PCOS and PCOS women: a comparative study
Background: Leptin, a hormone secreted by adipose tissues, controls body weight through regulation of appetite and thermogenesis. The present study was aimed to observe role of leptin in healthy and polycystic ovary syndrome (PCOS) women.Methods: Correlation between serum leptin and anthropometric, endocrine and metabolic profile was studied in 30 apparently healthy women (control group) and 38 PCOS women (PCOS group). Each group was stratified based on body mass Index (BMI), as normal weight (BMI<23) and overweight/obese (BMI>23).Results Leptin level was high in 30% control group and in 65.79% PCOS group. Mean leptin (ng/ml) in PCOS group was higher compared to control group (18±1.9 v/s 12±1.7, p<0.05). Mean leptin levels were higher in overweight/obese subgroup as compared to normal weight subgroup in both Control (p<0.05) and PCOS groups (p=<0.05). In control group, leptin showed positive correlation with waist circumference (WC) (r=-0.49, p<0.01) and negative correlation with Cholesterol: HDL ratio (p<0.05). In PCOS group, leptin showed positive correlation with BMI (r=0.377,p<0.05) and Triglyceride (r=0.34,<0.05) and negative correlation with Fasting Blood Glucose( FBG)(r=-0.33,p<0.05). In normal weight subgroup among control group (n=25), leptin showed positive correlation with LDL (r=0.49, p<0.05). In control overweight/obese subgroup (n=5), leptin showed positive correlation with Follicle Stimulating Hormone (FSH) (r=+1.0, p<0.05) and inverse correlation with testosterone(r=-1.0,p<0.05). In normal weight subgroup among PCOS group, leptin had a positive correlation with LDL: HDL ratio (r=0.488, p<0.05). Conclusions: Hyperleptinemia is common in obesity. Leptin controls glycemic status in patients with IR. Correlation of leptin with FSH and testosterone is influenced by obesity and PCOS. Leptin regulation of lipid homeostasis is influenced by obesity or PCOS
The effects of climatic fluctuations and extreme events on running water ecosystems
Most research on the effects of environmental change in freshwaters has focused on incremental changes in average conditions, rather than fluctuations or extreme events such as heatwaves, cold snaps, droughts, floods or wildfires, which may have even more profound consequences. Such events are commonly predicted to increase in frequency, intensity and duration with global climate change, with many systems being exposed to conditions with no recent historical precedent. We propose a mechanistic framework for predicting potential impacts of environmental fluctuations on running water ecosystems by scaling up effects of fluctuations from individuals to entire ecosystems. This framework requires integration of four key components: effects of the environment on individual metabolism, metabolic and biomechanical constraints on fluctuating species interactions, assembly dynamics of local food webs and mapping the dynamics of the meta-community onto ecosystem function. We illustrate the framework by developing a mathematical model of environmental fluctuations on dynamically assembling food webs. We highlight (currently limited) empirical evidence for emerging insights and theoretical predictions. For example, widely supported predictions about the effects of environmental fluctuations are: high vulnerability of species with high per capita metabolic demands such as large-bodied ones at the top of food webs; simplification of food web network structure and impaired energetic transfer efficiency; reduced resilience and top-down relative to bottom-up regulation of food web and ecosystem processes. We conclude by identifying key questions and challenges that need to be addressed to develop more accurate and predictive bio-assessments of the effects of fluctuations, and implications of fluctuations for management practices in an increasingly uncertain world
Comparison of Early Intervention Services vs Treatment as Usual for Early-Phase Psychosis A Systematic Review, Meta-analysis, and Meta-regression
A Continuum Robot and Control Interface for Surgical Assist in Fetoscopic Interventions
Twin-twin transfusion syndrome requires interventional treatment using a fetoscopically introduced laser to sever the shared blood supply between the fetuses. This is a delicate procedure relying on small instrumentation with limited articulation to guide the laser tip and a narrow field of view to visualize all relevant vascular connections. In this letter, we report on a mechatronic design for a comanipulated instrument that combines concentric tube actuation to a larger manipulator constrained by a remote centre of motion. A stereoscopic camera is mounted at the distal tip and used for imaging. Our mechanism provides enhanced dexterity and stability of the imaging device. We demonstrate that the imaging system can be used for computing geometry and enhancing the view at the operating site. Results using electromagnetic sensors for verification and comparison to visual odometry from the distal sensor show that our system is promising and can be developed further for multiple clinical needs in fetoscopic procedures
- …