2,362 research outputs found
Occurrence, Distribution and Seasonality of Watermolds in Selected Forest Ecosystems of Central Himalaya
Occurrence, Distribution and Seasonality of Watermolds in Selected Forest Ecosystems of Central Himalay
Dependence of dielectric constant and loss tangent on electric field in antiferroelectric squaric acid crystal
The double-time thermal Green function method with the symmetric and antisymmetric decoupling scheme and modified pseudospin model proposed by Li and Qin for squaric acid have been used in present study to discuss the effect of electric field on some dielectric properties. Expressions for shift, width, soft mode frequency, dielectric constant, loss and transition temperature have been evaluated. By fitting model values of physical quantities in the theoretical expressions thermal dependence of antiferroelectric mode frequency, dielectric constant and loss have been calculated in presence of electric field in the vicinity of transition temperature. Theoretical results are similar to other antiferroelectric crystals
BRST Quantization of Unimodular Gravity
We study the quantization of two versions of unimodular gravity, namely fully diffeomorphism-invariant unimodular gravity and unimodular gravity with fixed metric determinant, utilizing standard path integral approach. We derive the BRST symmetry of effective actions corresponding to several relevant gauge conditions. We observe that for some gauge conditions, the restricted gauge structure may complicate the formulation and effective actions, in particular, if the chosen gauge conditions involve the canonical momentum conjugate to the induced metric on the spatial hypersurface. The BRST symmetry is extended further to the finite field-dependent BRST transformation, in order to establish the mapping between different gauge conditions in each of the two versions of unimodular gravity.Peer reviewe
Influence of the RNase H domain of retroviral reverse transcriptases on the metal specificity and substrate selection of their polymerase domains
Reverse transcriptases from HIV-1 and MuLV respectively prefer Mg2+ and Mn2+ for their polymerase activity, with variable fidelity, on both RNA and DNA templates. The function of the RNase H domain with respect to these parameters is not yet understood. To evaluate this function, two chimeric enzymes were constructed by swapping the RNase H domains between HIV-1 RT and MuLV RT. Chimeric HIV-1 RT, having the RNase H domain of MuLV RT, inherited the divalent cation preference characteristic of MuLV RT on the DNA template with no significant change on the RNA template. Chimeric MuLV RT, likewise partially inherited the metal ion preference of HIV-1 RT. Unlike the wild-type MuLV RT, chimeric MuLV RT is able to use both Mn.dNTP and Mg.dNTP on the RNA template with similar efficiency, while a 30-fold higher preference for Mn.dNTP was seen on the DNA template. The metal preferences for the RNase H activity of chimeric HIV-1 RT and chimeric MuLV RT were, respectively, Mn2+ and Mg2+, a property acquired through their swapped RNase H domains. Chimeric HIV-1 RT displayed higher fidelity and discrimination against rNTPs than against dNTPs substrates, a property inherited from MuLV RT. The overall fidelity of the chimeric MuLV RT was decreased in comparison to the parental MuLV RT, suggesting that the RNase H domain profoundly influences the function of the polymerase domain
A Case Study on Improving Accessibility of Healthcare Care Facility in Low-resource Settings
Accessibility in a hospital is challenging for people in low-income countries due to a lack of accessible mediums to communicate wayfinding, accessibility, and healthcare information. This results in delays and stress but can also result in sub-optimal treatment or sometimes a complete lack of treatment for the visitors. Sensible physical and digital interventions can greatly ease the experience of visitors and reduce the work-related stress of healthcare providers. We present a case study on wayfinding and service design for a mega ophthalmic care facility that has a daily footfall of 2500 patients. From our mixed-methods study we identified: (i) there are very few accessible mediums available to communicate wayfinding, accessibility, and healthcare information; (ii) there is a lack of inclusively designed interventions to accommodate the diversity of visitors; (iii) spatial ambiguity and situational impairment due to crowd density exasperate the situation and (iv) there exist missing as well as misleading information. We developed a spectrum of solutions on the environmental and digital infrastructures available within this context to deliver wayfinding and procedural information. We completed a progressive intervention across digital and physical mediums over a duration of 18 months. This has shown the impact of each medium on visitors' experience. We found the choice of interface to access information depends on the ease of access, and ease of access depends on visitors' abilities. Therefore, both the environment and digital mediums are found to be useful for visitors. Based on these empirical findings, we draw recommendations for an inclusive service design that incorporates using elements of the environment, human and digital infrastructure to support a more positive healthcare visitors experience
Chemical Radioprotectors
Protection of biological systems against radiation damage is of paramount importance during accidental and unavoidable exposure to radiation. Several physico-chemical and biological factors collectively contribute to the damage caused by radiation and are, therefore, targets for developing radioprotectors. Work on the development of chemicals capable of protecting biological systemsfrom radiation damage was initiated nearly six decades ago with cysteine being the first molecule to be reported. Chemicals capable of scavenging free radicals, inducing oxygen depletion,antioxidants and modulators of immune response have been some of the radioprotectors extensively investigated with limited success. Mechanism of action of some chemical radioprotectors and their combinations have been elucidated, while further understanding is required in many instances. The present review elaborates on structure-activity relationship of some of the chemical radioprotectors, their evaluation, and assessment, limitation, and future prospects
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