2,827 research outputs found
Novel approach for optimization of fermentative condition for polyhydroxybutyrate (PHB) production by Alcaligenes sp. using Taguchi (DOE) methodology
Polyhydroxybutyrate (PHB) is a biodegradable thermoplastic polymer which is accumulated as energy reserve material by large number of microorganisms including bacteria, fungus and yeast under nutrient stress condition. In this study, efforts have been made to optimize PHB production by Alcaligenes sp. NCIM 5085 using Taguchi (DOE) methodology. This approach facilitates the study of interaction of a large number of variables spanned by factors and their settings with a smaller number of experiments, leading to considerable savings in time and cost for process optimization. Eight factors at two levels with an OA layout of L-12 were selected for proposed experimental design. PHB concentration was increased from 5.20 to 6.58 g/L under optimal cultural condition. Result validation showed 95% resemblance with the expected value.Key words: Polyhydroxybutyrate, Alcaligenes sp. Taguchi (DOE), orthogonal arrays layout
Biomarkers and Surrogate Endpoints in Uveitis: The Impact of Quantitative Imaging
PURPOSE: Uveitis is a major cause of sight loss across the world. The reliable assessment of intraocular inflammation in uveitis (‘disease activity') is essential in order to score disease severity and response to treatment. In this review, we describe how ‘quantitative imaging', the approach of using automated analysis and measurement algorithms across both standard and emerging imaging modalities, can develop objective instrument-based measures of disease activity.
METHODS: This is a narrative review based on searches of the current world literature using terms related to quantitative imaging techniques in uveitis, supplemented by clinical trial registry data, and expert knowledge of surrogate endpoints and outcome measures in ophthalmology.
RESULTS: Current measures of disease activity are largely based on subjective clinical estimation, and are relatively insensitive, with poor discrimination and reliability. The development of quantitative imaging in uveitis is most established in the use of optical coherence tomographic (OCT) measurement of central macular thickness (CMT) to measure severity of macular edema (ME). The transformative effect of CMT in clinical assessment of patients with ME provides a paradigm for the development and impact of other forms of quantitative imaging. Quantitative imaging approaches are now being developed and validated for other key inflammatory parameters such as anterior chamber cells, vitreous haze, retinovascular leakage, and chorioretinal infiltrates.
CONCLUSIONS: As new forms of quantitative imaging in uveitis are proposed, the uveitis community will need to evaluate these tools against the current subjective clinical estimates and reach a new consensus for how disease activity in uveitis should be measured. The development, validation, and adoption of sensitive and discriminatory measures of disease activity is an unmet need that has the potential to transform both drug development and routine clinical care for the patient with uveitis
Implementation pathway report: Community Resource Person An intervention by the Technical Support Unit Uttar Pradesh, India, February 2015
A report describing the methodology behind an implementation pathway for the Community Resource Person innovation being implemented by the Technical Support Unit (a large-scale collaboration between the Bill & Melinda Gates Foundation and the Uttar Pradesh government) in Uttar Pradesh, India
Spatiotemporal characterisation of Fire Severity Over a 23 Year Period in South-East Queensland using data collected with Landsat sensors: A preliminary study
Land management agencies are increasingly using multispectral satellite imagery to monitor post-fire ground conditions to guide effective conservation and asset protection management strategies. Estimates derived from such data can span over multiple decades and can be analysed to identify spatiotemporal burnt area patterns. Interestingly, fire severity is rarely derived from multi-decadal remote sensing datasets. Accordingly, in this study we explored the utility of imagery captured with Landsat sensors (5 TM, 7 ETM+ and 8 OLI) to characterise fire severity of burnt areas over a 23 year period in a national park with a woodland and heath ecosystem. The multi-temporal differenced normalised burn ratio (dNBR) was used to estimate fire severity for individual burnt areas, which were then aggregated to identify spatiotemporal patterns. Accuracy assessment was achieved using ground truth data collected with the Geometrically Structured Composite Burn Index (GeoCBI), which incorporates the fraction of cover (FCOV) of vegetation over the total plot. Our results indicated that Landsat imagery was ideal for significantly estimating fire severity (accuracy = 72 %, kappa = 0.63, P = < 0.001) in sclerophyll woodland and heath ecosystems. Further, we had interesting insight into the patterns of increased fire severity within specific vegetation types and across the study site
A solution blending route to ethylene propylene diene terpolymer/layered double hydroxide nanocomposites
Ethylene propylene diene terpolymer (EPDM)/MgAl layered double hydroxide (LDH) nanocomposites have been synthesized by solution intercalation using organically modified LDH (DS-LDH). The molecular level dispersion of LDH nanolayers has been verified by the disappearance of basal XRD peak of DS-LDH in the composites. The internal structures, of the nanocomposite with the dispersion nature of LDH particles in EPDM matrix have been studied by TEM and AFM. Thermogravimetric analysis (TGA) shows thermal stability of nanocomposites improved by ≈40 °C when 10% weight loss was selected as point of comparison. The degradation for pure EPDM is faster above 380 °C while in case of its nanocomposites, it is much slower
Activity Guided Isolation and Characterization of Antiplasmodial Agents of some Local medicinal Plants
Combined Plant Mixture (CPM) in ratio of 1:1 (Vitex doniana, Diospyros mesipiliformis, Acacia polyacantha, Parinari macrophylla, Ficus sycomorus and Parkia biglobosa) was extracted with methanol and screened for antimalarial activity. The CPM Methanol extract residue was suspended in water and fractionated with Hexane (HX), Ethylacetate (EA) and n-Butanol (BUT). The Methanolic CPM extract has shows some antimalarial activity with Mean Survival Times (MST) of 10.16 to 12.16 days. All the mice in control group were found dead on 14th day of study and one mice was still alive on 14th day in both the groups with 15% and 30% parasitaemia against Plasmodium yoelli nigeriensis N67 and Plasmodium berghei K173 respectively. The EA fraction was the most active against P. yoelli nigeriensis N67 having 2 mice surviving up to 14th day with 5.5% parasitaemia and MST of 13.4 days. Fractions of water (WT), HX and BUT have 12.5, 25, and 100% (dead) parasitaemia with mean survival times of 12.6, 9.33 and 8.5 days against 100% (dead) parasitaemia and 8.20 days of MST when compared with control. HX fraction was the most active against P. berghei K173 followed by BUT fraction with one mice surviving up to 14th day without parasitaemia but with MST of 15.0 and 13.5 days respectively. EA and WT fractions have 22.66 and 100% (dead) parasitaemia with mean survival times of 11.80 and 10.80 days respectively. Chromatographic separation of EA fraction of the CPM extract resulted in the isolation of Gallic acid (Figure 2, Fractions 79-83), 3β-OH-α-amyrin (Figure 3, Fractions 45-46), 5,7,3’,4’,5’- pentahydroxy-3-O-glucophyranoside flavones (Figure 4, Fractions 128-157)-[myricetin 3-O-β-rhamnopyranoside], 5,7,3’,4’ tetrahydroxy-3-o-glucopyranoside flavones(Figure 5, Fractions 126-141)-[quercetin 3-O-β-rhamnopyranoside], and 3,5,7,3’,4’-Pentahydroxy flavones (Figure 6, Fractions 87-112)-[quercetine]. The compounds were characterized using ESI-MS, IR, 1H 13C, HMBC/HSQC and COSY-NMR data. These findings suggest that the combined extracts possess antiplasmodial properties.Keywords: Antimalarial, combined plant mixture, 1H 13C NMR, activity guided fractionatio
Hubble Tension and Cosmological Imprints of Gauge Symmetry: as a case study
The current upper limit on at the time of CMB by Planck 2018
can place stringent constraints in the parameter space of BSM paradigms where
their additional interactions may affect neutrino decoupling. Motivated by this
fact in this paper we explore the consequences of light gauge boson ()
emerging from local symmetry in at the time of CMB.
First, we analyze the generic models with arbitrary charge assignments
for the SM fermions and show that, in the context of the generic
gauged models can be broadly classified into two categories, depending
on the charge assignments of first generation leptons. We then perform a
detailed analysis with two specific models: and
and explore the contribution in due to the
presence of realized in those models. For comparison, we also showcase the
constraints from low energy experiments like: Borexino, Xenon 1T, neutrino
trident, etc. We show that in a specific parameter space, particularly in the
low mass region of , the bound from (Planck 2018) is more
stringent than the experimental constraints. Additionally, a part of the
regions of the same parameter space may also relax the tension.Comment: typos fixed, main text 28 pages, 9 Figure
The role of carbon in life's blueprint and carbon cycle understanding earth's essential cycling system: benefits and harms to our planet
This abstract provides a concise overview of carbon, carbon dioxide, and the carbon cycle. Carbon is an essential element for life on Earth, serving as the building block of organic molecules found in living organisms. Carbon dioxide (CO2), a greenhouse gas, plays a dual role in supporting life through photosynthesis while also contributing to climate change when its concentration in the atmosphere increases due to human activities. The carbon cycle is a natural process that continuously cycles carbon between the atmosphere, oceans, land, and living organisms. It plays a vital role in regulating the Earth's climate, supporting plant growth through photosynthesis, sequestering carbon in natural sinks, and sustaining various ecosystems. However, human activities have disrupted the carbon cycle, leading to adverse effects such as climate change, ocean acidification, and ecosystem disturbances. Mitigating these harmful impacts requires global efforts to reduce carbon emissions, conserve forests, and adopt sustainable practices to restore the balance of the carbon cycle and ensure a more sustainable future
Dynamics of socio-economic factors affecting climate vulnerability and technology adoption: Evidence from Jodhpur district of Rajasthan
192-196Climate change and extreme weather fluctuations are the most threatening challenges to the farming communities especially in semi-arid tropics. The paper investigates socio-economic factors affecting vulnerability and adoption of innovations using micro-level survey data of 100 systematically selected farmers in the Jodhpur district of Rajasthan, India. The results reveal that higher income, irrigation and provision of seeds reduce climate vulnerability to a great extent. Several farm level strategies have been adopted by the farmers against climate induced stress, including change in cropping pattern, reduction in irrigation usage, use of drips and sprinklers and water conservation. In case of pearl millet cropping system, we found that adoption of wide row spacing is significantly influenced by the level of the farmer’s education, land size category, climate awareness and trainings programs. The study suggests that diversified crop sequence involving pearl millet-wheat-cluster bean-barley-onion, farmers’ adoption of suitable adaptation strategies and climate resilient technologies will improve with better awareness, education and farm governance with regard to climate change. Moreover, technologies especially indigenous ones suitable to the local contextual needs must be developed or fine-tuned and disseminated for reducing climate-induced vulnerability
Tunable CsPb(Br/Cl)3 perovskite nanocrystals and further advancement in designing light emitting fiber membranes
Cesium lead halide perovskite nanocrystals (NCs) have drawn a great deal of interest in optoelectronic and photonic applications due to their intrinsic and attractive photoluminescence properties. Though, their commercially viability is of concern due to their intrinsic instability. In this study, blue and green luminous PMMA-CsPbX3(X=Cl/Br) fibers were fabricated via forcespinning technique, where the polymer matrix encapsulated the NCs. Blue CsPbX3 NCs (b- CPX NCs) were synthesized at ambient conditions while blue to green CsPbX3 NCs (g-CPX NCs) fine color tuning was obtained after heat treatment at 150°C.Field emission scanning electron microscopy (FESEM) shows fibers with diameters in the single digit microscale. Efficient encapsulation of NCs in the PMMA fiber was confirmed using FTIR spectroscopy. UV visible spectra of the NCs suggested a quantum confinement effect. Pristine NCs shows bright blue and green emission from b-CPX and g-CPX NCs under UV irradiation (365 nm) which was successfully reproduced even upon encapsulation in the PMMA matrix. In both cases, the PMMA besides promoting QD encapsulation also enhanced the photoluminescent quantum yield (PLQY) from 25.5% to 31.1% (blue PMMA fibers) and 42.6% to 51.4% (green PMMA fibers) compare to bare NCs PLQY. The PMMA-CsPbX3(X=Cl/Br) also possessed narrow half-peak width compared to pristine NCs suggesting high color purity. This work provides a novel polymer fiber-based encapsulation approach to solve the intrinsic instability issues of CsPbX3 NCs, therefore prompting promising practical applications
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