Half Metallic Ferromagnetism and Transport Properties of Zinc Chalcogenides ZnX2Se4 (X = Ti,V, Cr) for Spintronic Applications

In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (T_c), spin polarization, half magnetic ferromagnetism and transport properties of ZnX₂Se₄ (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of T_c is perceived for ZnCr₂Se₄. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μ_B of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy ΔE _crystal, exchange energies Δ _x(d), Δ _x (pd) and exchange constants (N_o α and N_o β ). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0–400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 10¹¹ W/mK²) among studied compounds.     

Metal-free functionalized carbonized cotton for efficient solar steam generation and wastewater treatment

Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity. Materials for solar photothermal energy conversion are highly sought after for their cost savings, environmental friendliness and broad utility in many applications including domestic water heating and solar-driven desalination. Herein, we report the successful development of metal-free, low weight and cost effective functionalized carbonized cotton (CC) fibers for efficient solar water desalination and wastewater treatment. The CC fibers with nearly full solar spectrum absorption, efficient photo-thermal conversion and low-cost could provide excellent alternatives to the high-cost plasmonic-based materials for solar water desalination. We also report on a novel and simple device to mitigate the issues associated with conductive heat loss by utilizing the economically viable carbonized cotton materials as an irradiation surface placed on a low-density polyethylene foam that floats on the surface of seawater. The CC solar steam generation device exhibits average water evaporation rates of 0.9, 6.4 and 10.9 kg m⁻² h⁻¹ with impressive solar-to-vapor efficiencies of 59.2, 88.7 and 94.9% under 1, 5 and 8 sun illumination, respectively. Moreover, the device displays excellent durability showing stable evaporation rates over 10 steam generation cycles under 5 sun of solar intensity. Furthermore, the applicability of the CC device for the removal of organic dyes from contaminated water through solar steam generation is also demonstrated. The low-cost, simple design, high solar thermal evaporation efficiency, excellent stability and long-term durability make this CC device a perfect candidate for applications in seawater desalination and wastewater treatment by solar steam generation.

Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity.     

Outcome of transcatheter aortic valve implantation in high risk patients with severe aortic stenosis

Aim

To assess outcome of TAVI in high risk patients with severe symptomatic aortic stenosis.

Inhibition of the TRPC5 ion channel protects the kidney filter

An intact kidney filter is vital to retention of essential proteins in the blood and removal of waste from the body. Damage to the filtration barrier results in albumin loss in the urine, a hallmark of cardiovascular disease and kidney failure. Here we found that the ion channel TRPC5 mediates filtration barrier injury. Using Trpc5-KO mice, a small-molecule inhibitor of TRPC5, Ca²⁺ imaging in isolated kidney glomeruli, and live imagining of podocyte actin dynamics, we determined that loss of TRPC5 or its inhibition abrogates podocyte cytoskeletal remodeling. Inhibition or loss of TRPC5 prevented activation of the small GTP-binding protein Rac1 and stabilized synaptopodin. Importantly, genetic deletion or pharmacologic inhibition of TRPC5 protected mice from albuminuria. These data reveal that the Ca²⁺-permeable channel TRPC5 is an important determinant of albuminuria and identify TRPC5 inhibition as a therapeutic strategy for the prevention or treatment of proteinuric kidney disease.     

Sertoli cell prostaglandin D2 synthetase is a multifunctional molecule: its expression and regulation

PGD2 synthetase (PGD-S; PGH2 D-isomerase; EC 5.3.99.2) is a bifunctional protein first identified in the mammalian brain. It acts as a PGD2-producing enzyme and a retinoid transporter. PGD-S is present in the testis, where its protein and messenger RNA levels are similar to those in the brain. In view of its diversified regulatory functions, we investigated its regulation using primary cultures of Sertoli cells in vitro to assess its role in the testis. When Sertoli cells were cultured in serum-free medium to allow the formation of specialized junctions, it was found that PGD-S expression increased steadily with time, coinciding with the formation of inter-Sertoli junctions in vitro. However, neither germ cells (using a Sertoli/germ cell ratio between 1:1 and 1:30 when Sertoli cells were cultured at a density of 5x10(4) cells/cm2) nor germ cell-conditioned medium affected the expression of Sertoli cell PGD-S in vitro. These results thus unequivocally demonstrated that germ cells do not play a role in regulating testicular PGD-S expression. Although FSH, dihydrotestosterone, and testosterone had no apparent effect on Sertoli cell PGD-S expression, the addition of progesterone(1x10(-11) to 1x10(-9) M) and T3 (1x10(-11) to 1x10(-9) M) to Sertoli cell cultures elicited a significant increase in PGD-S expression by as much as 4.5- and 2.5 fold, respectively. As PGD-S is a known retinoid transporter, the effects of all-trans-retinoic acid and all-trans-retinal on Sertoli cell PGD-S expression were also assessed. Both compounds were found to induce Sertoli cell PGD-S expression. In summary, PGD-S is a putative Sertoli cell product whose expression is regulated by progesterone, metabolites of vitamin A, and T3. In view of its dual biological properties, a study of its regulation and physiology will yield new insights into understanding its role in the testis.     

Development and optimisation of atorvastatin calcium loaded self-nanoemulsifying drug delivery system (SNEDDS) for enhancing oral bioavailability: in vitro and in vivo evaluation

The objective of this study was to develop and optimise self-nanoemulsifying drug delivery system (SNEDDS) of atorvastatin calcium (ATC) for improving dissolution rate and eventually oral bioavailability. Ternary phase diagrams were constructed on basis of solubility and emulsification studies. The composition of ATC–SNEDDS was optimised using the Box–Behnken optimisation design. Optimised ATC–SNEDDS was characterised for various physicochemical properties. Pharmacokinetic, pharmacodynamic and histological findings were performed in rats. Optimised ATC–SNEDDS resulted in droplets size of 5.66?nm, zeta potential of ?19.52?mV, t₉₀ of 5.43?min and completely released ATC within 30?min irrespective of pH of the medium. Area under the curve of optimised ATC–SNEDDS in rats was 2.34-folds higher than ATC suspension. Pharmacodynamic studies revealed significant reduction in serum lipids of rats with fatty liver. Photomicrographs showed improvement in hepatocytes structure. In this study, we confirmed that ATC–SNEDDS would be a promising approach for improving oral bioavailability of ATC.     

Effect of topical anti-inflammatory drugs on corneal and limbal wound healing

PURPOSE: To examine the effect of topical treatment with either steroidal or nonsteroidal anti-inflammatory drugs (NSAIDs) on the wound healing of corneal and limbal incisions using histologic criteria. SETTING: Loyola University Medical Center, Maywood, Illinois, USA. METHODS: Eighteen eyes of 9 cats were used for the study. All right eyes received a temporal limbal incision and the left eyes, a clear corneal incision. All eyes were treated with ofloxacin 0.3% postoperatively for 3 days. The animals were equally divided among 3 groups. Group 1 received topical steroid drops (prednisolone acetate 1%) for 7 days maximum; Group 2 received topical NSAID drops (ketorolac tromethamine 0.5%) for 7 days maximum; Group 3 received no additional treatment. One animal from each group was killed and the eye enucleated 3, 7, or 28 days postoperatively. The eyes were processed for staining with hematoxylin-eosin and smooth muscle actin, and corneal sections were evaluated in a blind fashion by an ophthalmic pathologist. RESULTS: Three and 7 days after surgery (1) the limbal incision exhibited more prominent wound healing than the similarly treated clear corneal incision, and (2) the steroid-treated corneas had less wound healing than untreated or NSAID-treated corneas. At 28 days, the wounds in all eyes were almost completely healed. CONCLUSIONS: Limbal incisions heal faster than clear corneal incisions. Steroids, but not NSAIDs, inhibit wound healing. Cataract surgery using limbal incisions and postoperative topical NSAIDs may result in faster wound healing and provide a reduced risk of related postoperative complications.