55 research outputs found
Synthesis and characterization of solid SiO2/P2O5/ZrO2-PVP membrane for fuel cell applications
A novel polymer network membrane composed by SiO2/P2O5Ă‚Â/ZrO2-PVP was prepared to improve the proton conductivity of PVP membrane. Its physico-chemical properties were characterized using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), and solid-state nuclear magnetic resonance (NMR). XRD data shows that the crystallinity increases with increase in concentration of SiO2 andZrO2. Our results indicate the formation and interconnection of ion clusters. It is observed that this new membrane exhibits better proton conductivity as compared to the pristine membrane making them suitable for fuel cell applications
Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)
The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the
India-based Neutrino Observatory (INO) is designed to study the atmospheric
neutrinos and antineutrinos separately over a wide range of energies and path
lengths. The primary focus of this experiment is to explore the Earth matter
effects by observing the energy and zenith angle dependence of the atmospheric
neutrinos in the multi-GeV range. This study will be crucial to address some of
the outstanding issues in neutrino oscillation physics, including the
fundamental issue of neutrino mass hierarchy. In this document, we present the
physics potential of the detector as obtained from realistic detector
simulations. We describe the simulation framework, the neutrino interactions in
the detector, and the expected response of the detector to particles traversing
it. The ICAL detector can determine the energy and direction of the muons to a
high precision, and in addition, its sensitivity to multi-GeV hadrons increases
its physics reach substantially. Its charge identification capability, and
hence its ability to distinguish neutrinos from antineutrinos, makes it an
efficient detector for determining the neutrino mass hierarchy. In this report,
we outline the analyses carried out for the determination of neutrino mass
hierarchy and precision measurements of atmospheric neutrino mixing parameters
at ICAL, and give the expected physics reach of the detector with 10 years of
runtime. We also explore the potential of ICAL for probing new physics
scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration,
Contents identical with the version published in Pramana - J. Physic
Genomic data for 78 chickens from 14 populations
Background: Since the domestication of the red jungle fowls (Gallus gallus; dating back to~10 000 B.P.) in Asia, domestic chickens (Gallus gallus domesticus) have been subjected to the combined effects of natural selection and human-driven artificial selection; this has resulted in marked phenotypic diversity in a number of traits, including behavior, body composition, egg production, and skin color. Population genomic variations through diversifying selection have not been fully investigated. Findings: The whole genomes of 78 domestic chickens were sequenced to an average of 18-fold coverage for each bird. By combining this data with publicly available genomes of five wild red jungle fowls and eight Xishuangbanna game fowls, we conducted a comprehensive comparative genomics analysis of 91 chickens from 17 populations. After aligning ~21.30 gigabases (Gb) of high-quality data from each individual to the reference chicken genome, we identified ~6.44 million (M) single nucleotide polymorphisms (SNPs) for each population. These SNPs included 1.10 M novel SNPs in 17 populations that were absent in the current chicken dbSNP (Build 145) entries. Conclusions: The current data is important for population genetics and further studies in chickens and will serve as a valuable resource for investigating diversifying selection and candidate genes for selective breeding in chickens.Peer reviewedAnimal Scienc
Renal transplant in a lupus nephritis patient with β-thalassemia trait
Progression of proliferative lupus nephritis to end-stage renal disease is common. Anemia in chronic kidney disease has multifactorial etiology, but it is rarely associated with β- Thalassemia trait. Iron deficiency is common in hemodialysis patients due to increased blood loss. Microcytic hypochromic anemia may be due to iron deficiency, hemoglobinopathies and aluminum toxicity. Because chronic kidney disease is a chronic inflammatory state, it is difficult to exclude iron deficiency with classical biochemical markers. Treatment of anemia in chronic kidney disease is important as iron therapy may cause iron overload, increased susceptibility to infection, atherosclerosis and increased oxidative stress. Multiple blood transfusions may cause iron overload, risk of infection transmission and alloimmunization. Alloimmunization decreases donor pool and increases chances of rejection
Quetiapine Shortens the Lifespan of Caenorhabditis elegans through DOP-2, DAF-2 and RSKS-1
Recent studies implicate a key role of dopamine signaling in lifespan regulation. Our previous study found that quetiapine, an atypical antipsychotic drug that has antagonistic activity on dopamine D2-like receptors (D2Rs), shortened the lifespan of Caenorhabditis elegans (C. elegans). However, the detailed mechanism of this effect was not clear. In the present study, we evaluate the effect of quetiapine on aging and explore its underlying molecular mechanism. The results show that quetiapine shortened healthspan in C. elegans. The lifespan-shortening effect is dependent on DOP-2, a D2R expressed in worms. Quetiapine shortens lifespan through the C. elegans insulin and IGF-1 receptor DAF-2, but not the downstream Akt pathway. Quetiapine-induced lifespan reduction is dependent on RSKS-1, a key protein kinase that functions in mTOR signaling. In addition, the quetiapine effect is also related to mitochondrial function. These findings further support the key role of dopamine signaling in lifespan regulation and promote our insight into the mechanism of action of antipsychotic drugs
FOXO signaling pathways as therapeutic targets in cancer
Many transcription factors play a key role in cellular differentiation and the delineation of cell phenotype. Transcription factors are regulated by phosphorylation, ubiquitination, acetylation/deacetylation and interactions between two or more proteins controlling multiple signaling pathways. These pathways regulate different physiological processes and pathological events, such as cancer and other diseases. The Forkhead box O (FOXO) is one subfamily of the fork head transcription factor family with important roles in cell fate decisions and this subfamily is also suggested to play a pivotal functional role as a tumor suppressor in a wide range of cancers. During apoptosis, FOXOs are involved in mitochondria-dependent and –independent processes triggering the expression of death receptor ligands like Fas ligand, TNF apoptosis ligand and Bcl-X bNIP3, Bim from Bcl-2 family members. Different types of growth factors like insulin play a vital role in the regulation of FOXOs. The most important pathway interacting with FOXO in different types of cancers is the PI3K/AKT pathway. Some other important pathways such as the Ras-MEK-ERK, IKK and AMPK pathways are also associated with FOXOs in tumorigenesis. Therapeutically targeting the FOXO signaling pathway(s) could lead to the discovery and development of efficacious agents against some cancers, but this requires an enhanced understanding and knowledge of FOXO transcription factors and their regulation and functioning. This review focused on the current understanding of cell biology of FOXO transcription factors which relates to their potential role as targets for the treatment and prevention of human cancers. We also discuss drugs which are currently being used for cancer treatment along with their target pathways and also point out some potential drawbacks of those drugs, which further signifies the need for development of new drug strategies in the field of cancer treatment
Learning style preferences: A study of Pre-clinical Medical Students in Barbados
Introduction: Educators need to be aware of different learning
styles to effectively tailor instructional strategies and methods
to cater to the students’ learning needs and support a conductive
learning environment. The VARK [an acronym for visual (V),
aural (A), read/write (R) and kinesthetic (K)] instrument is
a useful model to assess learning styles. The aim of this study
was to use the VARK questionnaire to determine the learning
styles of pre-clinical medical students in order to compare the
perceived and assessed learning style preferences, assess gender
differences in learning style preferences, and determine whether
any relationships exists between awareness of learning styles and
academic grades, age, gender and learning modality.
Methods: The VARK questionnaire was administered to preclinical
students taking a variety of courses in the first three years
of the undergraduate MB BS degree programme at the Faculty of
Medical Sciences, The University of the West Indies, Cave Hill
Campus, Barbados in 2014.
Results: The majority of the students were multimodal learners
with no differences observed between males (59.5%) and females
(60.0%), with tetramodal being the most common. Read/write
(33.8%) followed by kinesthetic (32.5%) were the most common
learning style preferences. The sensory modality preference for
females was read/write (34.2%) and for males it was kinesthetic
(40.5%). Significant differences were observed between the
perceived and assessed learning style preferences with a
majority of visual and read/write learners correctly matching
their perceived to their actual learning styles. Awareness of
learning styles was associated with learning modality but not
with academic performance, age or gender. Overall, 60.7% of
high achievers used multimodal learning compared to 56.9%
low achievers.
Conclusion: The findings from this study indicated that the
VARK tool was useful in gathering information about different
learning styles, and might assist educators in designing blended
teaching strategies to cater to the students’ needs as well as help
the students in becoming aware of their learning style preferences
to enhance learning
- …