A simple method to predict different failure mode of sandwich composite panel with honeycomb core: application to marine structure

Peer Reviewe

Lavandula stoechas L alleviates dementia by preventing oxidative damage of cholinergic neurons in mice brain

Purpose: To ascertain if there is any scientific evidence for the folkloric use of Lavandula stoechas as a nootropic substance for memory-related disorders.Methods: Aqueous and n-hexane fractions of methanol extract of aerial parts of L. stoechas were used to explore their anti-amnesic activity. Male albino mice weighing 25 - 30 g were organized in ten groups (G-I to G-X) and treated for seven days. On 7th and 8th day, behavioral studies were conducted using elevated plus maze, hole-board and light-dark paradigms. Furthermore, biochemical studies were performed on brain homogenates of mice.Results: Half-maximal inhibitory concentration (IC50) values for aqueous and n-hexane fractions of L. stoechas were recorded as 35.14 and 357.42 μg/mL respectively, as compared to the standard, ascorbic acid (51.39 μg/mL). Behavioral test results indicate that the aqueous fraction showed significant (p < 0.001) build-up of memory in mice, compared to n-hexane fraction. Similarly, the aqueous fraction significantly (p < 0.001) reduced the level of acetylcholinesterase and malondialdehyde as well as elevation of natural antioxidants, viz, superoxide dismutase, catalase and glutathione in brain tissues.Conclusion: The aqueous fraction of L. stoechas is a memory-enhancing agent. Its antioxidant activity prevents the loss of memory by providing defense against neurodegeneration.Keywords: Acetylcholinesterase, Elevated plus maze, Behavioral studies, Lavandula stoechas, Malondialdehyd

Lavandula stoechas (L) a Very Potent Antioxidant Attenuates Dementia in Scopolamine Induced Memory Deficit Mice

The objective of the current project was to explore the pharmacotherapeutic role of Lavandula stoechas (L) for the management of dementia. Dementia is considered a global challenge of current century seeking special attention of pharmacologists to explore its best remedies. Methanolic extract of aerial parts of L. stoechas was tested for phytochemical analysis along with free radical scavenging activity. Behavioral studies were performed on scopolamine induced amnesic mice by using elevated plus maze (EPM), light and dark test and hole board paradigms. Biochemical investigations were made after decapitating the mice. Their brains were isolated for biochemical estimation of acetylcholinesterase (AChE), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Phytochemical study ensured the presence of total phenolic contents (285.91 ± 0.75 mg of GAE/g of extract), total flavonoids (134.06 ± 0.63 mg of RE/g of extract), total tannins (149.60 ± 0.93 mg of TAE/g of extract) and free radical scavenging activity (IC50 value = 76.73 μg/ml found by DPPH method). Behavioral studies indicated that animals of GVII showed higher inflexion ratio (0.40 ± 0.03) for EPM, spent most of time (227.17 ± 2.13 s) in dark area of light dark test and had many hole pockings (39.83 ± 1.88) for hole board paradigm. Moreover, biochemical studies revealed that methanolic extract of L. stoechas (800 mg/kg/p.o.) significantly (P < 0.001) reduced brain AChE and MDA levels while improved SOD, CAT, and GSH levels. Thus the findings suggest that L. stoechas stabilizes memory by enhancing cholinergic neurotransmission and by providing defense against oxidative stress in mice brain

A micro-macro strategy for ship structural analysis with FETI-DP method

International audienceIn the analysis of ship structures at small scale, with structural details heterogeneities and because there is only one prototype produced, which is the final product, the designers rely on finite element simulations. The finite element discretization of such structure, leads to a huge global numerical model, that suffers for computational cost and memory resource that may be unaffordable. In such a case, a multi-scale analysis should be performed. The classical local-global analysis that is used by engineers has several limitations such as: - structure details are not periodic, therefore classical homogenization methods are not easily applicable; - edge effects are not take into account; - zooming techniques are not easy to use: the gluing they require with the global scale often introduces artificial edge effects. This paper presents a micro-macro strategy based on the domain decomposition FETI-DP method as the solver in analysis of ship structure. With this approach, the two scales (micro and macro) are coupled during the iterations of the solver and we can consider the structural details in areas of interest, area where the fine mesh is used and a sub-domain is located. Performances are discussed and results in term of convergence are presented for several examples

Comparison of clinico-pathological characteristics and survival of recurrent ovarian cancer patients on seven different chemo-protocols

Despite the growing prevalence of ovarian cancer (OC) in Pakistan, no literature evidence exists regarding its clinic-pathological characteristics, survival and compliance of patients with recurrent ovarian cancer and various chemo-protocols. An observational study was conducted by enrolling 251 recurrent OC patients on 7 different chemo-protocols, from a specialized cancer care hospital, Lahore, Pakistan, using convenient judgmental sampling. The study was conducted for a period of 6 months. Most of the patients were between 18 and 70 years of age, with IIIC FIGO stage and papillary serous histological grade. As per RECIST, improved partial response (PR) (63.3 %) and complete response (CR) (52.1 %) was observed in the CP (carboplatin + paclitaxel) arm, substantiated by improved median progression free survival (PFS) and overall survival (OS) in CP and CD (carboplatin + docetaxel) arms, respectively, yet with no significant differences in survival curves, PFS (p = 0.12) and OS (p = 0.22). Interestingly, the highest and the lowest patient non-compliance were observed in CG (carboplatin + gemcitabine) (81.6 %) and paclitaxel (4.5 %) arms, resp. As per the hazard model for survival, topotecan showed significant association with the therapy related events/deaths compared to other protocols. These data suggest that CP regimen exhibited improved clinical efficacy and decreased toxicity related non-compliance in recurrent ovarian cancer patients of Lahore

Cytotoxic and antiviral potentials of Euphorbia milii var. splendens leaf against Peste des petits ruminant virus

Purpose: To determine the cytotoxic and antiviral potentials of Euphorbia milii var. splendens leaf against Peste des petits ruminants virus (PPRV). Methods: The methanol extract, as well as n- hexane, chloroform, ethyl acetate, and n- butanol fractions of E. milii leaves were screened for cytotoxic and antiviral activities against PPRV using Vero cell line and 3-(4,5-dimethylthiazol-2-yl)-2,diphenyltetrazolium bromide (MTT) assay. Results: Non-cytotoxic concentrations with cell survival rate (CSP) greater than 50 % were considered virucidal. Methanol extract and fractions produced significant (p < 0.05) effects at all test concentrations against PPRV. The 50 % cytotoxic concentration (CC50) calculated was ≤ 25 µg/mL for extract and fractions. In antiviral assay, ethyl acetate, n-hexane, and n-butanol fractions at all test concentrations ranging from 1.56 - 800 µg/mL were non-virucidal; even at their non-cytotoxic concentrations these fractions did not show antiviral activities. However, the methanol extract and its chloroform fractions showed significant (p < 0.05) virucidal potential. Conclusion: The results suggest that further isolation of antiviral constituents from the fractions may open new horizons for the development of new antiviral agents

Hepato- and nephro-protective as well as hypoglycemic effects of sea buckthorn berries (Hippophae rhamnoides L.) in rabbits and humans

The hepato- and nephro-protective effects of sea buckthorn berries (Hippophae rhamnoides L) were investigated in paracetamol-induced toxicity in animals and hypoglycemic effects in type II diabetic patients. Crude drug preparation and its methanol extract have shown a profound decrease in paracetamol-induced elevated serum levels of liver and kidney functions under investigation, which suggests a possible therapeutic role of its constituents in hepatic injury and altered kidney functions. Similarly, in human patients with raised glucose levels, sea buckthorn shows hypoglycemic effect which could likely make it a potential therapeutic agent to mange type II diabetes mellitus. However, further investigations are required to unveil the mechanism of action of sea buckthorn preparations in these ailments.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Hepatoprotective effect of aqeous methanolic extract of Rumex dentatus in paracetamol induced hepatotoxicity in mice

Rumex dentatus is well known plant of Polygonaceae family which is widely used in traditional medicine to treat gastrointestinal tract. R. dentatus at doses 250 and 500 mg/kg significance decreased (p<0.001) the elevated level of ALT, AST, ALP and bilirubin induced by paracetamol and results are comparable (p<0.001) with silymarin. The results were supported by histopathological investigations, phytochemical screening and detection of hepatoprotective active constituents e.g quercetin, kaempferol, myricetin by HPLC. So, it is concluded that R. dentatus has hepatoprotective effect against paracetamol liver damage in mice

Exploring the Correlation between Hα\rm{H}\alpha-to-UV Ratio and Burstiness for Typical Star-forming Galaxies at z∼2z\sim2

The $\rm{H}\alpha$-to-UV luminosity ratio ($L(\rm H\alpha)/L(\rm UV)$) is often used to probe SFHs of star-forming galaxies and it is important to validate it against other proxies for burstiness. To address this issue, we present a statistical analysis of the resolved distribution of $\Sigma_{\rm{SFR}}$ as well as stellar age and their correlations with the globally measured $L(\rm H\alpha)/L(\rm UV)$ for a sample of 310 star-forming galaxies in two redshift bins of $1.37 < z < 1.70$ and $2.09 < z < 2.61$ observed by the MOSDEF survey. We use the multi-waveband CANDELS/3D-HST imaging of MOSDEF galaxies to construct $\Sigma_{\rm{SFR}}$ and stellar age maps. We analyze the composite rest-frame far-UV spectra of a subsample of MOSDEF targets obtained by the Keck/LRIS, which includes 124 star-forming galaxies (MOSDEF-LRIS) at redshifts $1.4 < z < 2.6$, to examine the average stellar population properties, and the strength of age-sensitive FUV spectral features in bins of $L(\rm H\alpha)/L(\rm UV)$. Our results show no significant evidence that individual galaxies with higher $L(\rm H\alpha)/L(\rm UV)$ are undergoing a burst of star formation based on the resolved distribution of $\Sigma_{\rm{SFR}}$ of individual star-forming galaxies. We segregate the sample into subsets with low and high $L(\rm H\alpha)/L(\rm UV)$. The high-$L(\rm H\alpha)/L(\rm UV)$ subset exhibits, on average, an age of $\log[\rm{Age/yr}]$ = 8.0, compared to $\log[\rm{Age/yr}]$ = 8.4 for the low-$L(\rm H\alpha)/L(\rm UV)$ galaxies, though the difference in age is significant at only the $2\sigma$ level. Furthermore, we find no variation in the strengths of Siiv$\lambda\lambda1393, 1402$ and Civ$\lambda\lambda1548, 1550$ P-Cygni features from massive stars between the two subsamples.Comment: 16 pages, 10 figures, published by the Monthly Notices of the Royal Astronomical Societ