49 research outputs found
AerosolâCloud Interaction: A Case Study
MODerate Resolution Imaging Spectroradiometer (MODIS) retrieved aerosol and cloud products at the nine selected stations over Western Himalayan and Deccan Plateau regions were inferred to bring out their salient features and to investigate aerosolâcloud interaction. Annually, Ă
ngström exponent (AE) decreases with aerosol optical depth (AOD) while in winter it increases with AOD at most of the stations. Results bring out positive and/or negative association between AOD and almost all the cloud parameters over the selected stations. Aerosol indirect effect (AIE) is quantified for fixed liquid water path (LWP) bins ranging from 1 to 350âg/m2 at an interval of 25âg/m2 for three categories of stations, viz., CATâH, CATâM, and CATâL based on heavy, moderate, and low aerosol loading, respectively. AIE is negative at CATâH (â0.04â±â0.14), while it is positive at CATâM (0.01â±â0.07) and CATâL (0.10â±â0.48). During winter, negative AIE has been observed for all three categories. In preâmonsoon, the majority of LWP bins (86% at CATâH and 60% at CATâM) showed positive AIE, while about 71% of LWP bins indicted negative AIE at CATâL. However, during monsoon about 63â71% of LWP bins showed negative AIE at these categories. Study elucidates the influence of factors like cloud type, cloud dynamics/thermodynamics on aerosolâcloud interactions
Cellular and Molecular Mediators of Neuroinflammation in the Pathogenesis of Parkinsonâs Disease
Advances in Neuroprotective Ingredients of Medicinal Herbs by Using Cellular and Animal Models of Parkinsonâs Disease
Parkinsonâs disease (PD) is a multifactorial disorder, which is neuropathologically identified by age-dependent neurodegeneration of dopaminergic neurons in the substantia nigra. Development of symptomatic treatments has been partly successful for PD research, but there remain a number of inadequacies in therapeutic strategies for the disease. The pathogenesis of PD remains intricate, and the present anti-PD treatments appears to be clinically insufficient. Comprehensive research on discovery of novel drug candidates has demonstrated that natural products, such as medicinal herbs, plant extracts, and their secondary metabolites, have great potential as therapeutics with neuroprotective activity in PD. Recent preclinical studies suggest that a number of herbal medicines and their bioactive ingredients can be developed into optimum pharmaceuticals for treating PD. In many countries, traditional herbal medicines are used to prevent or treat neurodegenerative disorders, and some have been developed as nutraceuticals or functional foods. Here we focus on recent advances of the evidence-linked neuroprotective activity of bioactive ingredients of herbal origin in cellular and animal models of PD research
Critical weather limits for paddy rice under diverse ecosystems of India
Rice yields are largely influenced by variability in weather. Here, we demonstrate the effect of weather variables viz., maximum and minimum temperatures, rainfall, morning and evening relative humidity, bright sunshine hours on the yield of rice cv. Swarna, grown across five rice ecologies of India through field experiments during kharif (wet) season (Jun-Sept.). Critical thresholds of weather elements were identified for achieving above average, average and below average yield for each ecology. The investigation could determine how different weather elements individually and collectively affect rice yield in different rice ecosystems of India. While a sudden increase in minimum temperature by 8-10 °C (> 30 °C) during reproductive period resulted in 40-50 per cent yield reduction at Mohanpur, a sudden decrease (< 20 °C) caused yield decline at Dapoli. The higher yields may be attributed to a significant difference in bright sunshine hours between reproductive phases of above-average and below-average yield years (ranging from 2.8 to 7.8 hours during P5 stages and 1.7 to 5.1 during P4 stages). Rice cultivar Swarna performed differently at various sowing dates in a location as well as across locations (6650 kg ha-1 at Dapoli to 1101 kg ha-1 at Samastipur). It was also found that across all locations, the above average yield could be associated with higher range of maximum temperature compared to that of below average yield. Principal component analysis explained 77 per cent of cumulative variance among the variables at first growth stage, whereas 70 per cent at second growth stage followed by 74 per cent and 66 per cent at subsequent growth stages. We found that coastal locations, in contrast to inland ones, could maximize the yield potential of the cultivar Swarna, due to the longer duration of days between panicle initiation to physiological maturity. We anticipate that the location-specific thresholds of weather factors will encourage rice production techniques that are climate resilient
Science with the Daksha High Energy Transients Mission
We present the science case for the proposed Daksha high energy transients
mission. Daksha will comprise of two satellites covering the entire sky from
1~keV to ~MeV. The primary objectives of the mission are to discover and
characterize electromagnetic counterparts to gravitational wave source; and to
study Gamma Ray Bursts (GRBs). Daksha is a versatile all-sky monitor that can
address a wide variety of science cases. With its broadband spectral response,
high sensitivity, and continuous all-sky coverage, it will discover fainter and
rarer sources than any other existing or proposed mission. Daksha can make key
strides in GRB research with polarization studies, prompt soft spectroscopy,
and fine time-resolved spectral studies. Daksha will provide continuous
monitoring of X-ray pulsars. It will detect magnetar outbursts and high energy
counterparts to Fast Radio Bursts. Using Earth occultation to measure source
fluxes, the two satellites together will obtain daily flux measurements of
bright hard X-ray sources including active galactic nuclei, X-ray binaries, and
slow transients like Novae. Correlation studies between the two satellites can
be used to probe primordial black holes through lensing. Daksha will have a set
of detectors continuously pointing towards the Sun, providing excellent hard
X-ray monitoring data. Closer to home, the high sensitivity and time resolution
of Daksha can be leveraged for the characterization of Terrestrial Gamma-ray
Flashes.Comment: 19 pages, 7 figures. Submitted to ApJ. More details about the mission
at https://www.dakshasat.in
Recent Update on the Role of Chinese Material Medica and Formulations in Diabetic Retinopathy
Diabetes mellitus is one of the most frequent endocrine disorders, affecting populations worldwide. Diabetic retinopathy (DR) is the most frequent microvascular complication of diabetes in patients aged 20 and over. Major complications of DR include intraocular neovascularization, inter-retinal edema, hemorrhage, exudates and microaneurysms. Therefore, timely medical attention and prevention are required. At present, laser-assisted therapy and other operational procedures are the most common treatment for DR. However, these treatments can cause retinal damage and scarring. Also, use of the majority of traditional medicines is not supported by clinical evidence. However, due to accumulating scientific evidence, traditional natural medications may assist in delaying or preventing the progression of DR. This review focuses on evidence for the role of traditional natural medicines and their mechanisms of action and pharmacological test results in relation to the progression of DR
Promising cannabinoid-based therapies for Parkinsonâs disease: motor symptoms to neuroprotection
Atractylenolide-I Protects Human SH-SY5Y Cells from 1-Methyl-4-Phenylpyridinium-Induced Apoptotic Cell Death
Oxidative stress and apoptosis are the major mechanisms that induce dopaminergic cell death. Our study investigates the protective effects of atractylenolide-I (ATR-I) on 1-methyl-4-phenylpyridinium (MPP+)-induced cytotoxicity in human dopaminergic SH-SY5Y cells, as well as its underlying mechanism. Our experimental data indicates that ATR-I significantly inhibits the loss of cell viability induced by MPP+ in SH-SY5Y cells. To further unravel the mechanism, we examined the effect of ATR-I on MPP+-induced apoptotic cell death characterized by an increase in the Bax/Bcl-2 mRNA ratio, the release of cytochrome-c, and the activation of caspase-3 leading to elevated levels of cleaved poly(ADP-ribose) polymerase (PARP) resulting in SH-SY5Y cell death. Our results demonstrated that ATR-I decreases the level of pro-apoptotic proteins induced by MPP+ and also restored Bax/Bcl-2 mRNA levels, which are critical for inducing apoptosis. In addition, ATR-I demonstrated a significant increase in the protein expression of heme-oxygenase in MPP+-treated SH-SY5Y cells. These results suggest that the pharmacological effect of ATR-I may be, at least in part, caused by the reduction in pro-apoptotic signals and also by induction of anti-oxidant protein
Neuroprotective Role of Atractylenolide-I in an In Vitro and In Vivo Model of Parkinsonâs Disease
Parkinsonâs disease (PD) is an age-related neurological disorder characterized by a loss of dopaminergic neurons within the midbrain. Neuroinflammation has been nominated as one of the key pathogenic features of PD. Recently, the inadequate pharmacotherapy and adverse effects of conventional drugs have spurred the development of unconventional medications in the treatment of PD. The purpose of this study is to investigate the anti-neuroinflammatory mechanisms of Atractylenolide-I (ATR-I) in in vivo and in vitro models of PD. Nitrite assay was measured via Griess reaction in lipopolysaccharide (LPS) stimulated BV-2 cells. mRNA and protein levels were determined by a reverse transcription-polymerase chain reaction (RT-PCR) and immunoblot analysis, respectively. Further, flow cytometry, immunocytochemistry, and immunohistochemistry were employed in BV-2 cells and MPTP-intoxicated C57BL6/J mice. Pre-treatment with ATR-I attenuated the inflammatory response in BV-2 cells by abating the nuclear translocation of nuclear factor-ÎșB (NF-ÎșB) and by inducing heme oxygenase-1 (HO-1). The intraperitoneal administration of ATR-I reversed MPTP-induced behavioral deficits, decreased microglial activation, and conferred protection to dopaminergic neurons in the mouse model of PD. Our experimental reports establish the involvement of multiple benevolent molecular events by ATR-I in MPTP-induced toxicity, which may aid in the development of ATR-I as a new therapeutic agent for the treatment of PD
Only spinal fixation as treatment of prolapsed cervical intervertebral disc in patients presenting with myelopathy
Aim: An alternative form of surgical treatment of prolapsed cervical intervertebral disc in patients presenting with symptoms related to myelopathy is discussed. The treatment involved fixation of the affected spinal segments and aimed at arthrodesis. No direct manipulation or handling of the disc was done.
Materials and Methods: During the period August 2010 to June 2017, 16 patients presenting with symptoms attributed to myelopathy and diagnosed to have prolapsed cervical intervertebral disc were surgically treated by spinal stabilization. There were 11 males and 5 females and their ages ranged from 20 to 66 years (average: 40.6 years). Apart from clinical and radiological indicators, the number of spinal segments that were stabilized depended on direct observation of facetal morphology, alignment, and stability. Surgery involved distraction-fixation of facets using Goel facet spacer (8 patients), transarticular facetal fixation (5 patients) using screws or a combination of both facetal spacer, and transarticular screws (3 patients).
Results: All patients had âremarkableâ clinical improvement in the immediate postoperative period as assessed by visual analog scale, Goel's clinical grading, and Japanese Orthopedic Association scores. Follow-up ranged from 3 to 84 months (average: 50 months). The herniated disc regressed or disappeared at follow-up radiological assessment that ranged from 24 h to 3 months after surgery.
Conclusions: Spinal segmental fixation aiming at arthrodesis with or without distraction of facets and without any direct surgical manipulation in the disc space or removal of the prolapsed portion of the disc can be considered in the armamentarium of the surgeon