Crystallographic,morphological and photoluminescent investigations of Tb3+-doped YAlO3 perovskites for lighting applications

Terbium(III)-doped yttrium aluminate perovskite (YAP:xTb³⁺) (x = 0.01–0.08 mol) was synthesized using a simple gel-combustion method. Structural elucidations were performed using X-ray diffraction (XRD) and Rietveld analysis. Fourier-transform infrared spectral studies validated the efficient synthesis of designed doped samples. Transmission electron microscopic images showed the agglomerated irregular dimensions of the synthesized nanocrystalline materials. When excited at 251 nm, a strong emissive line attributed to ⁵D₄ → ⁷F₅ electronic transition was observed at 545 nm (green emission). The maximum luminescence was found at the optimized concentration (0.05 mol) of Tb³⁺ ions; this emission was quenched by dipolar–dipolar (d–d) interactions. Chromaticity (x and y) and correlated colour temperature parameters were obtained by analysing the emission profiles. Finally, the colour coordinates of nanophosphors were closer to the National Television Standards Committee green coordinates, which replicates their potency in the design and architecture of R-G-B-based white LEDs.     

Deletions at short direct repeats and base substitutions are characteristic mutations for bleomycin-induced double- and single-strand breaks, respectively, in a human shuttle vector system.

Using the radiomimetic drug, bleomycin, we have determined the mutagenic potential of DNA strand breaks in the shuttle vector pZ189 in human fibroblasts. The bleomycin treatment conditions used produce strand breaks with 3'-phosphoglycolate termini as > 95% of the detectable dose-dependent lesions. Breaks with this end group represent 50% of the strand break damage produced by ionizing radiation. We report that such strand breaks are mutagenic lesions. The type of mutation produced is largely determined by the type of strand break on the plasmid (i.e. single versus double). Mutagenesis studies with purified DNA forms showed that nicked plasmids (i.e. those containing single-strand breaks) predominantly produce base substitutions, the majority of which are multiples, which presumably originate from error-prone polymerase activity at strand break sites. In contrast, repair of linear plasmids (i.e. those containing double-strand breaks) mainly results in deletions at short direct repeat sequences, indicating the involvement of illegitimate recombination. The data characterize the nature of mutations produced by single- and double-strand breaks in human cells, and suggests that deletions at direct repeats may be a 'signature' mutation for the processing of DNA double-strand breaks.     

Regulation of glutamine synthetase I fromRhizobium meliloti

Glutamine synthetase I fromRhizobium meliloti was found to be inhibited by adenosine 5-monophosphate, alanine, glycine, carbamyl phosphate, cytidine 5-triphosphate, tryptophan, histidine, and glucosamine-6-phosphate. Each inhibitor was independent in its action and the effect was cumulative when more than one inhibitor was added.     

Fc epsilon receptor mediated Ca2+ influx into mast cells is modulated by the concentration of cytosolic free Ca2+ ions.

The relationship between the Fc epsilon receptor mediated stimulation of mast cells and the Ca2+ signal it induces were studied using thapsigargin (TG), a blocker of the endoplasmic reticulum Ca2+ pump. TG induced, in mucosal mast cells (RBL-2H3 line), a dose-dependent and an InsP3-independent increase in [Ca2+]i (from resting levels of 83-150 nM to 600-680 nM), and a secretory response amounting to 30-50% of that observed upon Fc epsilon RI clustering. The TG induced rise of [Ca2+]i is most probably provided by both arrest of its uptake by the endoplasmic reticulum and influx from the medium. Thus, Ca2+ influx in mast cells may be modulated by the [Ca2+]i level.     

Promising applications of cold plasma for microbial safety,chemical decontamination and quality enhancement in fruits

Consumers’ demand is increasing for safe foods without impairing the phytochemical and sensory quality. In turn, it has increased research interest in the exploration of innovative food processing technologies. Cold plasma technology is getting popularity now days owing to its high efficacy in decontamination of microbes in fruit and fruit-based products. As a on-thermal approach, plasma processing maintains the quality of fruits and minimizes the thermal effects on nutritional properties. Cold plasma is also exploited for inactivating enzymes and degrading pesticides as both are directly related with quality loss and presently are most important concerns in fresh produce industry. The present review covers the influence of cold plasma technology on reducing microbial risks and enhancing the quality attributes in fruits.     

Dimethyl fumarate protects thioacetamide‐induced liver damage in rats: Studies on Nrf2, NLRP3, and NF‐κB

The present study was designed to investigate the hepatoprotective potential of dimethyl fumarate (DMF) against thioacetamide (TAA)‐induced liver damage. Wistar rats were treated with DMF (12.5, 25, and 50 mg/kg/day, orally) and TAA (200 mg/kg intraperitoneally, every third day) for 6 consecutive weeks. TAA exposure significantly reduced body weight, increased liver weight and index, and intervention with DMF did not ameliorate these parameters. DMF treatment significantly restored TAA‐induced increase in the levels of aspartate aminotransferase, alanine aminotransferase, γ‐glutamyl transferase, total bilirubin, uric acid, malondialdehyde, reduced glutathione, and histopathological findings such as inflammatory cell infiltration, deposition of collagen, necrosis, and bridging fibrosis. DMF treatment significantly ameliorated TAA‐induced hepatic stellate cell activation, increase in inflammatory cascade markers (NACHT, LRR, and PYD domains‐containing protein 3; NLRP3, apoptosis‐associated speck like protein containing a caspase recruitment domain; ASC, caspase‐1, nuclear factor‐kappa B; NF‐κB, interleukin‐6), fibrogenic makers (α‐smooth muscle actin; ɑ‐SMA, transforming growth factor; TGF‐β1, fibronectin, collagen 1) and antioxidant markers (nuclear factor (erythroid‐derived 2)‐like factor 2; Nrf2, superoxide dismutase‐1; SOD‐1, catalase). The present findings concluded that DMF protects against TAA‐induced hepatic damage mediated through the downregulation of inflammatory cascades and upregulation of antioxidant status.     

Mating behaviour and behavioural ecology of a Predatory Wasp,Symmorphus allobrogus (de Saussure) (Hymenoptera: Eumeninae)

This paper represents an attempt to investigate the mating behaviour of Symmorphus allobrogus, explaining the willingness of male to mount and copulate. The male displays including mode and frequency of antennation and position while copulating, the displays further comprises of intensity and frequency of rejecting behaviour. The presence of the male’s copulatory and postcopulatory courtship studies, understands the maintenance of monandry. The wasp has numerous secondary sexual characters, and the mating behaviour follows a phyletic and the specific sexual mating characters in context of sexual selection. The duration of mating phases and the number of male antennation series during precopulatory, copulatory and postcopulatory phases of mounting, differs significantly. Mating success depends mostly on the activities of male in the premounting phase and the behaviour of both sexes has a roughly equal importance for it in precopulatory phase. While during copulation, activity of male has little influence on its duration; however, behaviour of female has crucial effect, inducing its earlier termination.     

Viral impacts on honey bee populations: A review

Honey bee is vital for pollination and ecological services, boosting crops productivity in terms of quality and quantity and production of colony products: wax, royal jelly, bee venom, honey, pollen and propolis. Honey bees are most important plant pollinators and almost one third of diet depends on bee’s pollination, worth billions of dollars. Hence the role that honey bees have in environment and their economic importance in food production, their health is of dominant significance. Honey bees can be infected by various pathogens like: viruses, bacteria, fungi, or infested by parasitic mites. At least more than 20 viruses have been identified to infect honey bees worldwide, generally from Dicistroviridae as well as Iflaviridae families, like ABPV (Acute Bee Paralysis Virus), BQCV (Black Queen Cell Virus), KBV (Kashmir Bee Virus), SBV (Sacbrood Virus), CBPV (Chronic bee paralysis virus), SBPV (Slow Bee Paralysis Virus) along with IAPV (Israeli acute paralysis virus), and DWV (Deformed Wing Virus) are prominent and cause infections harmful for honey bee colonies health. This issue about honey bee viruses demonstrates remarkably how diverse this field is, and considerable work has to be done to get a comprehensive interpretation of the bee virology.