A comparative study of microstructural and magnetic properties of lsmo: NiFe2O4 nanocomposites prepared by microwave and solid state route

The present work deals with the preparation and the characterization of nickel ferrite and lanthanum strontium manganese oxide composites. The composites were prepared in two different routes i.e. in-situ route and solid state routes. The composites were prepared with three different ratios of the phases in each individual route. The ratios were 20LSMO:80NFO, 40LSMO:60NFO and 50LSMO:50NFO. The composites synthesized were subjected to cauterization by XRD, SEM, DSC/TG and M-H curve. The values obtained from the composites prepared from the in-situ method were compared with the values obtained from simple solid state methods. There were differences in the porosity values of the two methods. All the samples are characterized using XRD and found to be rhombohedral LSMO and cubic NFO phases. The crystallite size was found to be less than 50 nm. From SEM it was seen that the porosity of in-situ process samples is more than that of solid state process. It was observed that as the concentration of the NFO in the samples increased the magnetic properties also improved. The saturation magnetization (Ms) and coercivity (Hc) value for NFO comes out to be 52.7 emu/g and 74 Oe

Division Algebras and Quantum Theory

Quantum theory may be formulated using Hilbert spaces over any of the three associative normed division algebras: the real numbers, the complex numbers and the quaternions. Indeed, these three choices appear naturally in a number of axiomatic approaches. However, there are internal problems with real or quaternionic quantum theory. Here we argue that these problems can be resolved if we treat real, complex and quaternionic quantum theory as part of a unified structure. Dyson called this structure the "three-fold way". It is perhaps easiest to see it in the study of irreducible unitary representations of groups on complex Hilbert spaces. These representations come in three kinds: those that are not isomorphic to their own dual (the truly "complex" representations), those that are self-dual thanks to a symmetric bilinear pairing (which are "real", in that they are the complexifications of representations on real Hilbert spaces), and those that are self-dual thanks to an antisymmetric bilinear pairing (which are "quaternionic", in that they are the underlying complex representations of representations on quaternionic Hilbert spaces). This three-fold classification sheds light on the physics of time reversal symmetry, and it already plays an important role in particle physics. More generally, Hilbert spaces of any one of the three kinds - real, complex and quaternionic - can be seen as Hilbert spaces of the other kinds, equipped with extra structure.Comment: 30 pages, 3 encapsulated Postscript figure

PIEZOELECTRIC SYSTEMS AS AN ALTERNATIVE ENERGY SOURCE / PJEZOELEKTRINIŲ ENERGIJOS SURINKIMO SISTEMŲ APŽVALGA

The article gives an overview of the problems and solutions related to energy harvesting systems used for power supply of low power electronics systems. Power density is the main parameter describing the efficiency of energy harvesting systems. Piezoelectric energy harvesting systems demonstrate a high value of power density, and therefore the article presents an overview of piezoelectric energy harvesting systems and their components. Also, a summary of the terms that affect the efficiency of piezoelectric energy harvesting systems has been presented. Santrauka Straipsnyje apžvelgiamos problemos ir sprendimai, susiję su elektrinės energijos tiekimu mažos galios elektronikos sistemoms, taikant energijos surinkimo iš aplinkos technologijas. Vienas iš pagrindinių energijos surinkimo sistemas apibūdinančių parametrų yra galios tankis. Pjezoelektrinė energijos surinkimo technologija pasižymi vienu iš didžiausių galios tankiu, todėl straipsnyje išsamiai nagrinėjami pjezoelektriniai kinetinės energijos keitikliai, apžvelgiamos keitiklių konstrukcijos, jų sudedamosios dalys, išskiriamos technologinės sąlygos, darančios įtaką keitiklių efektyvumui. Reikšminiai žodžiai: energijos surinkimas; pjezoelektrinis efektas; pjezoelektriniai keitikliai; mažos galios elektronika

Survival Benefit of Statins in Hemodialysis Patients Awaiting Renal Transplantation

End-stage renal disease (ESRD) patients have extraordinarily high cardiovascular risk and mortality, yet the benefit of statins in this population remains unclear based on the randomized trials. We investigated the prognostic value of statins in a large, pure cohort of prospectively recruited patients with ESRD awaiting renal transplantation, and being followed up in a dedicated cardiac clinic. We prospectively collected demographic, clinical, laboratory, and pharmacological data on 423 consecutive ESRD patients on hemodialysis awaiting renal transplantation. Survival analysis was performed as a function of statin therapy. The baseline characteristics were as follows: age 57 ± 11 years, males 64%, diabetes mellitus in 68%, known coronary artery disease in 30%, left ventricular (LV) ejection fraction 61 ± 11%. Over a mean follow-up of 2 years, there were 43 deaths. Adjusted for age, gender, hypertension, body mass index, diabetes mellitus, coronary artery disease, smoking, and treatment with angiotensin converting enzyme inhibitor, β blocker, and antiplatelet medications, statin use was a predictor of lower mortality (hazard ratio 0.30, 95% confidence interval 0.11–0.79, p = 0.01). This beneficial effect of statin was supported by propensity score analysis (p = 0.02) and was consistent across all clinical subgroups. The benefit of statins seemed to be greater in those with LV hypertrophy and smoking. Statin therapy in hemodialysis patients awaiting renal transplant is independently associated with better survival supporting its use in this high-risk population

International Journal of Experimental Biology

Not AvailableThe decapod crustacean Penaeus monodon survives large fluctuations in salinity through osmoregulation in which Na+/ K+-ATPase (NKA) activity in the gills plays a central role, Adult P. monodon specimens were gradually acclimatized to 5, 25 and 35% salinities and maintained for 20 days to observe long term alterations in NKA expression. Specific NKA activity assayed in gill tissues was found to be 3 folds higher at 5% compared to 25% (isosmotic salinity) and 0.48 folds lower at 35%. The enzyme was immunolocalized in gills using mouse q-5 monoclonal antibody that cross reacts with P. monodon NKA a-subunit. At 5% the immunopositive cells were distributed on lamellar tips and basal lamellar epithelium of the secondary gill filaments and their number was visibly higher. At both 25% and 35% NKA positive cells were observed in the inter-lamellar region but the expression was more pronounced at 25% Gill architecture was normal at all salinities. However, the 1.5 fold increase in NKA a-subunit mRNA at 5% measured by quantitative RT-PCR (QRT-PCR) using EFIa as reference gene was not statistically significant. The study confirms the osmoregulating ability of P. monodon like other crustaceans at lower salinities. It is likely that significant increase in NKA transcript level happens at an earlier time point. At higher salinities all three methods record only marginal or no change from isosmotic controls confirming the hypothesis that the animal largely osmoconforms in hyperosmotic environment