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1.
Glob Food Sec ; 41: 100754, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38957381

RESUMEN

This study examines the impact of India's export restrictions on domestic retail rice prices using a dynamic panel GARCH model. The findings suggest that export restrictions are not a sufficient condition to lower domestic prices. Export restrictions are associated with lower retail price volatility in the East Zone. Moreover, the international price transmission to a sample of Asian and African economies shows that all countries are vulnerable, but the degree and kinds of vulnerability differ. Rice exporters appear to be the most susceptible as domestic prices increase in these countries. Rice importers are also vulnerable because of price increases, but the increases are less than in countries where the private sector decides on import quantities.

2.
Phys Chem Chem Phys ; 26(22): 16309-16319, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38804891

RESUMEN

A low-temperature method was developed to synthesize orange-red luminescence phosphor-doped carbon dots (CDs) without complicated purification procedures. These CDs showed excitation wavelength-independent narrow emission (photo-luminescence quantum yield, Φf ∼ 12 to 22%) with single exponential time-resolved decay in weakly polar/non-polar solvents, indicating the presence of one kind of chromophore. In contrast, the same CDs showed excitation wavelength-dependent broad emission (Φf ∼ 1 to 8%) with multi-exponential fluorescence decay in polar solvents. These CDs exhibited poor solubility in polar solvents, resulting in CD aggregates contributed by excitation wavelength-dependent weak luminescence. The CDs embedded in polymethyl methacrylate (PMMA) polymer film displayed bright orange-red fluorescence under UV 365 nm illumination, indicating their potential application in solid-state luminescence. Further, an analytical method was developed for the naked-eye detection of trifluoracetic acid (red emission) and triethylamine (green emission) under UV 365 nm illumination with reversible two switch-mode luminescence. Additionally, this efficient orange-red luminescence of CDs was utilized for possible bioimaging applications with negligible cytotoxicity in 3T3 mouse fibroblast cells.

3.
Phys Chem Chem Phys ; 26(17): 13350-13363, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38639928

RESUMEN

Ionic liquids (ILs) are liquid salts composed of cations and anions, known for their significant local heterogeneity at the molecular level. To understand the microheterogeneity with regard to their local polarity and local viscosity, we have used two structurally similar but chemically distinguishable fluorescent probes: Nile red (NR), a neutral molecule, and Nile blue sulfate (NBS), a charged molecule. A comparative study of the response of the two probes to the molecular level heterogeneity of ILs is expected to provide a better clarity of understanding regarding the charged polar domain and the uncharged hydrophobic domain of ILs. Towards this, we synthesized two butyrolactam-based protic ionic liquids (PILs), i.e., BTF and BTD, with the same ionic headgroup ([BT]+) and different alkyl tails ([RCOO]-), where {R = H, C11H23}. BTF has no significant hydrophobic domain, whereas BTD has a larger hydrophobic domain. Temperature-dependent fluorescence parameters such as fluorescence intensity, lifetime, and anisotropy were measured for both NR and NBS molecules. The use of a pair of structurally similar but ionically different probes enables differential estimation of parameters like the microviscosity of a domain using the fluorescence anisotropy parameter (r). The absorption and emission spectra of both probe molecules are observed to be blue shifted upon going from BTF to BTD. NR showed a significant blue shift in absorption and emission band maxima. Conversely, NBS exhibited a small wavelength shift, possibly influenced by the preferred location of their charged head group domain. Temperature-dependent rotational relaxation time (θ) of NR in BTD is smaller than that of NBS by 60-70%, indicating that stronger charge-charge interactions exist between the polar domain of BTD and NBS. Moreover, it is observed that the local viscosity of the BTF IL around both probes is similar, whereas there is a considerable difference for the BTD IL. These results are an indication that NBS being charged prefers to locate itself in the charged head group region of the IL, whereas NR being neutral tends to reside both in the hydrophobic domain and in the head group but is predominantly located in the hydrophobic domain.

4.
Front Public Health ; 12: 1332511, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560431

RESUMEN

Introduction: This study empirically investigates the attitude of tobacco and alcohol consumers towards health insurance purchase in India. The study aims to determine the factors which plays a significant role in determining the purchase intention of health insurance among tobacco and alcohol consumers. Methods: We propose an extended theory of planned behavior (TPB) model comprising factors like attitude, subjective norms, perceived behavior control, perceived usefulness, perceived product risk, and intention to purchase. We collected responses from 420 tobacco and alcohol consumers through a Google Form link shared via different social media platforms. SPSS has been used to perform exploratory factor analysis, whereas AMOS has been used to validate the constructs, confirm the relationships among the variables, and analyze the data. Results: The analysis outcomes demonstrate that subjective norms, perceived product risk, and perceived behavioral control are the factors that have a positive and significant effect on health insurance purchase intention among consumers. Discussion: This research offers valuable insights to the insurance sector, government officials, policymakers, and academicians. Insurance companies may consider the criteria analysed when creating policies to promote the expansion of the health insurance sector.


Asunto(s)
Intención , Lobelia , Humanos , Encuestas y Cuestionarios , Actitud , Seguro de Salud
5.
Langmuir ; 40(10): 5106-5120, 2024 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-38427698

RESUMEN

The present study focuses on exploring the physical properties of lipid membranes based on the polyhydroxy oxanorbornane (PH-ONB) headgroup, designed as synthetic analogues of naturally occurring archaeal lipid membranes. Specifically, we study two variants of PH-ONB headgroup-based lipids differing in the number of hydroxy groups present in the headgroup, with one having two hydroxy groups (ONB-2OH) and the other having three (ONB-3OH). These lipids form stable bilayer membranes. The study begins with a comprehensive analysis of the fluorescence characteristics of nitrobenzoxadiazole (NBD)-tagged ONB-based lipids in different solvent environments and within a model lipid membrane 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). Subsequently, the physical properties of the ONB-based membranes were examined by using an NBD-tagged ONB-based probe and a commonly used extrinsic 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescent probe. The steady-state and time-resolved fluorescence properties of the NBD-tagged ONB-based probe and DPH were used to compare the physical properties of the ONB-based membranes, including polarity, fluidity, phase transition, order, hydration, location, heterogeneity, and rotational diffusion. The solid gel to liquid crystalline phase transition temperatures of ONB-2OH and ONB-3OH lipid membranes are found to be (68 ± 1) °C and (74 ± 1) °C, respectively. The variation in organization (size), fluidity, and phase transition temperature of ONB-based lipid membranes is explained by the extent of hydrogen bonding interactions between lipid head groups. ONB-based membranes exhibit characteristics similar to those of phospholipid membranes and possess a notably high phase transition temperature. These properties make them a promising and cost-effective synthetic alternative to archaeal lipid membranes with a wide range of potential applications.


Asunto(s)
Colorantes Fluorescentes , Fosfolípidos , Colorantes Fluorescentes/química , Fosfolípidos/química , Fenómenos Químicos , Temperatura , Transición de Fase , Membrana Dobles de Lípidos/química , Fosfatidilcolinas/química
6.
Malar J ; 22(1): 375, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38072967

RESUMEN

BACKGROUND: Resistance against artemisinin-based combination therapy is one of the challenges to malaria control and elimination globally. Mutations in different genes (Pfdhfr, Pfdhps, Pfk-13 and Pfmdr1) confer resistance to artesunate and sulfadoxine-pyrimethamine (AS + SP) were analysed from Mandla district, Madhya Pradesh, to assess the effectiveness of the current treatment regimen against uncomplicated Plasmodium falciparum. METHODS: Dried blood spots were collected during the active fever survey and mass screening and treatment activities as part of the Malaria Elimination Demonstration Project (MEDP) from 2019 to 2020. Isolated DNA samples were used to amplify the Pfdhfr, Pfdhps, Pfk13 and Pfmdr1 genes using nested PCR and sequenced for mutation analysis using the Sanger sequencing method. RESULTS: A total of 393 samples were subjected to PCR amplification, sequencing and sequence analysis; 199, 215, 235, and 141 samples were successfully sequenced for Pfdhfr, Pfdhps, Pfk13, Pfmdr1, respectively. Analysis revealed that the 53.3% double mutation (C59R, S108N) in Pfdhfr, 89.3% single mutation (G437A) in Pfdhps, 13.5% single mutants (N86Y), and 51.1% synonymous mutations in Pfmdr1 in the study area. Five different non-synonymous and two synonymous point mutations found in Pfk13, which were not associated to artemisinin resistance. CONCLUSION: The study has found that mutations linked to SP resistance are increasing in frequency, which may reduce the effectiveness of this drug as a future partner in artemisinin-based combinations. No evidence of mutations linked to artemisinin resistance in Pfk13 was found, suggesting that parasites are sensitive to artemisinin derivatives in the study area. These findings are a baseline for routine molecular surveillance to proactively identify the emergence and spread of artemisinin-resistant parasites.


Asunto(s)
Antimaláricos , Artemisininas , Malaria Falciparum , Malaria , Humanos , Plasmodium falciparum , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Pirimetamina/uso terapéutico , Sulfadoxina/uso terapéutico , Artemisininas/farmacología , Artemisininas/uso terapéutico , Malaria/tratamiento farmacológico , Biomarcadores , Resistencia a Medicamentos/genética , India , Combinación de Medicamentos , Malaria Falciparum/parasitología , Proteínas Protozoarias/genética , Proteínas Protozoarias/uso terapéutico
7.
World Dev ; 171: 106367, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37916196

RESUMEN

This study investigates the effect of married couples' joint decision-making on rice variety selection on rice productivity-a measure of food security. The study uses the 2016 Rice Monitoring Survey and the endogenous switching regression (ESR) method. Results show that rice farms with joint decision-makers (husband and wife) would have higher yields, particularly in households that adopted MRVGen1 (before 1986) rice varieties. Thus, families with joint-decision making have higher food security. Intervention programs for food insecurity should acknowledge and incorporate information regarding the persons responsible for making rice varietal decisions and the characteristics of modern rice varieties to ensure food security.

8.
Phys Chem Chem Phys ; 25(42): 29327-29340, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37877192

RESUMEN

The present work explores the photophysical, electrochemical, and fluorescence polarization properties of a group of π-conjugated phenylethynyl-2,1,3-benzothiadiazole derivatives (BTDs) bearing different electron-donating (ED) or electron-withdrawing (EW) substituents at the para position of the phenylethynyl moiety. The BTDs were synthesized through the Sonogashira cross-coupling reaction between 4-bromo-2,1,3-benzothiadiazole and the respective para-substituted phenylethynyl derivatives. The BTDs with the EW-substituents show relatively weak solvatochromic behavior, while the BTDs with the strong ED-substituents like methoxy and N,N-dimethylamino-based substituents (BTDPhOMe and BTDPhNMe2) exhibit a pronounced solvatochromic behavior. The change in dipole moments in the excited states of the derivatives was calculated using Lippert-Mataga plots. The conclusions drawn on the spectral behavior of the molecules could be rationalized by TD-DFT calculations involving electron density difference (EDD) maps that correlate with the ICT characteristics of the molecules. The experimental and theoretical calculations reveal that the BTDs with the strong ED-substituents (strong push-pull type BTDs) have a strong ICT character in the excited state. These strong push-pull type BTDs show high fluorescence quantum yield (ΦF) in apolar solvents and low ΦF in polar solvents. In contrast, the BTDs with the weak ED-substituents (weak push-pull type BTDs) and EW-substituents (pull-pull type BTDs) have a weaker ICT character with low ΦF in apolar and high ΦF in polar solvent media. There is good a agreement among the HOMO-LUMO band gaps obtained from absorption spectroscopy and electrochemical studies and theoretical calculations. The fluorescence anisotropy measurement in the glycerol medium shows that the studied BTDs generally exhibit higher sensitivity towards microviscosity than the traditional DPH fluorescence anisotropy probe.

9.
Sci Total Environ ; 904: 166806, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37678526

RESUMEN

Real-time reservoir operation using inflow and irrigation demand forecasts can help reservoir system managers make effective water management decisions. Forecasting of inflow and irrigation demands is challenging, owing to the variability of the weather variables that affect inflows and irrigation demands. In this context, bias-corrected Global Forecasting System (GFS) forecasts are used here in a hybrid approach (reservoir module with Long Short Term Memory (LSTM)) to forecast the reservoir inflows. Concurrently, the bias-corrected GFS forecasts are used in irrigation demand module to forecast the irrigation demands. The 'Scaled Distribution Mapping' method is used to bias-correct the GFS data of 1-5 days lead. The study area is the Damodar river basin, India, consisting of five major reservoirs: Tenughat and Konar located upstream of Panchet, and Tilaya situated upstream of Maithon. With the upstream reservoir outflow forecasts, the inflows are forecasted in Panchet and Maithon reservoirs with NSE values of 0.88-0.96 and 0.78-0.88, respectively, up to a 5-day lead. The irrigation demand module with bias-corrected GFS forecasts forecasted the irrigation demands close to the irrigation demands with the observed weather data. The percentage errors in irrigation demand forecasts of the Kharif (June-October) season at 1-5 days lead are 9.45 %, -15.45 %, -20.52 %, -26.36 %, -27.31 %, respectively. On the contrary, percentage errors in irrigation demand forecasts of Rabi (November-February) and Boro (January-May) are in the range of 8.17-8.79 % and 3.48-8.06 %, respectively. With the inflows and irrigation demand forecasts, the Panchet and Maithon reservoirs satisfied the downstream demands and reduced the floods. The inflow and irrigation demand forecasts, based on the GFS forecasts, have substantial potential for real-time reservoir operation, leading to efficient water management downstream.

10.
PLoS One ; 18(8): e0289745, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37556495

RESUMEN

Pegfilgrastim is administered as an adjunct to chemotherapy to reduce the incidence of febrile neutropenia and associated infectious complications. Lupin's Pegfilgrastim is a proposed biosimilar to the U.S.-referenced Neulasta®. Demonstration of biosimilarity requires extensive physicochemical and functional characterization of the biosimilar, and demonstration of analytical similarity to the reference product, in addition to clinical studies. This work is a case study for demonstrating the analytical similarity of Armlupeg (Lupin's Pegfilgrastim) to Neulasta® with respect to structural and physicochemical attributes using several robust, orthogonal, and state-of-the-art techniques including high-end liquid chromatography, mass spectrometry, and spectroscopy techniques; circular dichroism; differential scanning calorimetry; nuclear magnetic resonance; analytical ultracentrifugation; and micro-flow imaging. Functional similarity was demonstrated using an in vitro cell proliferation assay to measure relative potency and surface plasmon resonance to measure receptor binding kinetics. Furthermore, comparative forced-degradation studies were performed to study the degradation of the products under stress conditions. The product attributes were ranked based on a critical quality attributes risk score according to their potential clinical impact. Based on criticality, all analyses were statistically evaluated to conclude analytical similarity. Lupin's Pegfilgrastim was comparable to Neulasta® as demonstrated via structural, functional, and purity analyses. Lupin's Pegfilgrastim complied with the quality and statistical ranges established using Neulasta®. Both products follow the same degradation pathways under stress conditions as observed in the forced-degradation studies. No new impurity or degradation product was observed in Lupin's Pegfilgrastim. These data conclusively demonstrate the analytical similarity of Lupin's Pegfilgrastim and Neulasta®.


Asunto(s)
Biosimilares Farmacéuticos , Biosimilares Farmacéuticos/uso terapéutico , Filgrastim , Polietilenglicoles/química , Proyectos de Investigación
11.
Proc Natl Acad Sci U S A ; 120(28): e2219825120, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399379

RESUMEN

Compound drought and heatwave (CDHW) events have garnered increased attention due to their significant impacts on agriculture, energy, water resources, and ecosystems. We quantify the projected future shifts in CDHW characteristics (such as frequency, duration, and severity) due to continued anthropogenic warming relative to the baseline recent observed period (1982 to 2019). We combine weekly drought and heatwave information for 26 climate divisions across the globe, employing historical and projected model output from eight Coupled Model Intercomparison Project 6 GCMs and three Shared Socioeconomic Pathways. Statistically significant trends are revealed in the CDHW characteristics for both recent observed and model simulated future period (2020 to 2099). East Africa, North Australia, East North America, Central Asia, Central Europe, and Southeastern South America show the greatest increase in frequency through the late 21st century. The Southern Hemisphere displays a greater projected increase in CDHW occurrence, while the Northern Hemisphere displays a greater increase in CDHW severity. Regional warmings play a significant role in CDHW changes in most regions. These findings have implications for minimizing the impacts of extreme events and developing adaptation and mitigation policies to cope with increased risk on water, energy, and food sectors in critical geographical regions.

12.
J Environ Manage ; 344: 118423, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37356329

RESUMEN

This study uses a nationally representative rural household survey from China, the difference-in-difference, three-step approach, and Seemingly Unrelated Regression methods to assess the impacts of China's new agricultural subsidy on chemical fertilizer use, heterogeneity effect, and mechanism. The results show that, first, the new agriculture subsidy reduces the use of chemical fertilizer by about 7.2 percent. A series of robustness tests confirm the finding. Second, the heterogeneity analysis shows that the subsidy's negative impact on fertilizer use is substantially greater among younger farmers than among older farmers. The negative effect also is significantly more in the main grain-producing areas than in non-grain-producing regions in China. Third, the mediating effect analysis shows that farmland scale mediates 8.3 percent of fertilizer use, and the adoption of agricultural machinery mediates 48.6 percent of fertilizer use. Our findings underscore the positive role that reforming the agrarian subsidy policy plays in sustainable development.


Asunto(s)
Agricultura , Fertilizantes , Humanos , Fertilizantes/análisis , Agricultura/métodos , Granjas , Agricultores , China
13.
Environ Manage ; 71(5): 950-964, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36759399

RESUMEN

Adoption of agroforestry in the early spring under the green growth initiative programs, such as the Billion Trees Afforestation Project, has positively impacted crop productivity and plantation success in Pakistan. However, the timely adoption decision of agroforestry in the Hindu Kush Himalayan is still low, particularly among smallholders. Using a mixed-method approach, we examine the factors influencing smallholder households and community-level timely agroforestry adoption decisions. Findings show that the early and later decision-makers farmers had agricultural lands on riversides and primarily adopted agroforestry to protect their crops from devastating effects of winds and floods. In contrast, late adoption decision-makers adopted agroforestry for income diversification. Results of our logit model show that several household and community-level factors influence smallholders' timely adoption of agroforestry. The factors that positively affect the timely adoption of agroforestry include age-related factors, education, and the establishment/existence of functional community-based organizations. In contrast, political conflicts and tenure insecurity negatively affect smallholders' timely adoption of agroforestry. In-depth interviews with Village Development Committees members revealed that terrace farming, farms on riversides, communities without access to other energy sources, population growth, and low farm acreage ensured the timely adoption of agroforestry. The policy recommendations include strengthening collaborative efforts among community members, especially engaging educated old-aged farmers (elders of traditional communities) to increase adoption rates and land tenure security to ensure timely agroforestry adoption under the newly launched 10-BTAP.


Asunto(s)
Agricultura , Árboles , Humanos , Persona de Mediana Edad , Anciano , Granjas , Agricultores , Renta
14.
Malar J ; 22(1): 62, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36810077

RESUMEN

BACKGROUND: Global malaria cases rose by 14 million, and deaths by 69,000, in 2020. In India, a 46% decline has been reported between 2020 and 2019. In 2017, the Malaria Elimination Demonstration Project conducted a needs-assessment of the Accredited Social Health Activists (ASHAs) of Mandla district. This survey revealed the inadequate level of knowledge in malaria diagnosis and treatment. Subsequently, a training programme was launched for enhancing malaria-related knowledge of ASHAs. The present study was conducted in 2021 to evaluate the impact of training on malaria-related knowledge and practices of ASHAs in Mandla. This assessment was also done in two adjoining districts: Balaghat and Dindori. METHODS: A cross-sectional survey using a structured questionnaire was administered to ASHAs to measure their knowledge and practices related to malaria etiology, prevention, diagnosis, and treatment. A comparison of information collected from these three districts was performed using simple descriptive statistics, comparison of means and multivariate logistic regression analysis. RESULTS: Significant improvement was noted amongst ASHAs of district Mandla between 2017 (baseline) and 2021 (endline) in knowledge related to malaria transmission, preventive measures, adherence to the national drug policy, diagnosis using rapid diagnostic tests, and identification of age group-specific, colour-coded artemisinin combination therapy blister packs (p < 0.05). The multivariate logistic regression analysis revealed that odds of Mandla baseline was 0.39, 0.48, 0.34, and 0.07 times lower for malaria-related knowledge on disease etiology, prevention, diagnosis, and treatment, respectively (p < 0.001). Further, participants in districts Balaghat and Dindori showed significantly lower odds for knowledge (p < 0.001) and treatment practices (p < 0.01) compared to Mandla endline. Education, attended training, having a malaria learner's guide, and minimum 10 years' work experience were potential predictors for good treatment practices. CONCLUSION: The findings of the study unequivocally establishes significant improvement in overall malaria-related knowledge and practices of ASHAs in Mandla as a result of periodic training and capacity building efforts. The study suggests that learnings from Mandla district could be helpful in improving level of knowledge and practices among frontline health workers.


Asunto(s)
Malaria , Humanos , Estudios Transversales , India , Agentes Comunitarios de Salud , Encuestas y Cuestionarios
15.
Nat Commun ; 14(1): 144, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36627287

RESUMEN

Quantifying the spatial and interconnected structure of regional to continental scale droughts is one of the unsolved global hydrology problems, which is important for understanding the looming risk of mega-scale droughts and the resulting water and food scarcity and their cascading impact on the worldwide economy. Using a Complex Network analysis, this study explores the topological characteristics of global drought events based on the self-calibrated Palmer Drought Severity Index. Event Synchronization is used to measure the strength of association between the onset of droughts at different spatial locations within the time lag of 1-3 months. The network coefficients derived from the synchronization network indicate a highly heterogeneous connectivity structure underlying global drought events. Drought hotspot regions such as Southern Europe, Northeast Brazil, Australia, and Northwest USA behave as drought hubs that synchronize regionally and with other hubs at inter-continental or even inter-hemispheric scale. This observed affinity among drought hubs is equivalent to the 'rich-club phenomenon' in Network Theory, where 'rich' nodes (here, drought hubs) are tightly interconnected to form a club, implicating the possibility of simultaneous large-scale droughts over multiple continents.


Asunto(s)
Sequías , Hidrología , Europa (Continente) , Brasil , Agua
16.
Nat Commun ; 14(1): 277, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36650142

RESUMEN

Climate change amplifies dry and hot extremes, yet the mechanism, extent, scope, and temporal scale of causal linkages between dry and hot extremes remain underexplored. Here using the concept of system dynamics, we investigate cross-scale interactions within dry-to-hot and hot-to-dry extreme event networks and quantify the magnitude, temporal-scale, and physical drivers of cascading effects (CEs) of drying-on-heating and vice-versa, across the globe. We find that locations exhibiting exceptionally strong CE (hotspots) for dry-to-hot and hot-to-dry extremes generally coincide. However, the CEs differ strongly in their timescale of interaction, hydroclimatic drivers, and sensitivity to changes in the soil-plant-atmosphere continuum and background aridity. The CE of drying-on-heating in the hotspot locations reaches its peak immediately driven by the compounding influence of vapor pressure deficit, potential evapotranspiration, and precipitation. In contrast, the CE of heating-on-drying peaks gradually dominated by concurrent changes in potential evapotranspiration, precipitation, and net-radiation with the effect of vapor pressure deficit being strongly controlled by ecosystem isohydricity and background aridity. Our results help improve our understanding of the causal linkages and the predictability of compound extremes and related impacts.


Asunto(s)
Sequías , Ecosistema , Atmósfera , Cambio Climático , Suelo
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 290: 122257, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36565504

RESUMEN

Herein, excitation wavelength-independent, tunable emissive and amphiphilic CDs with high quantum yield were synthesized by a low-temperature oxidation method employing banana peel waste as a carbon source. These CDs showed longer wavelength emissions (green to yellow) independent of the excitation wavelength when dispersed in different polar to non-polar solvents. The quantum yields of the same CDs were 9-32% in different solvent polarities for different emissions. On the other hand, a large stokes-shifted emission (∼9606 cm-1) was observed for CDs in the non-polar and weak polar solvents. The particle size of CDs increases from a hydrophobic to a hydrophilic environment with the change in emission colour from yellow to green. A polar and a non-polar host matrix were used to overcome the limitation of aggregation-caused quenching of CDs in the solid state to obtain bright emissions. These CDs were potentially used for naked-eye detection of trifluoroacetic acid (TFA) by changing the emission colour from yellow to orange under UV 365 nm. Sensing of TFA was also shown reversibly switch emission colour and average lifetime for multiple cycles. Additionally, the highly emissive CDs show negligible cytotoxicity in 3T3 fibroblast cells, indicating possible bioimaging applications in 3T3 cells.


Asunto(s)
Puntos Cuánticos , Animales , Ratones , Puntos Cuánticos/química , Carbono/química , Solventes/química , Tamaño de la Partícula
18.
Phys Chem Chem Phys ; 25(3): 1957-1969, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36541448

RESUMEN

Organic push-pull molecules contain donor and acceptor moieties connected via π-linkages through which intramolecular electron charge transfer (ICT) can occur in the ground and excited states; giving these molecules interesting photophysical properties. The molecules chosen in this work are some basic phenylethynylanthracene derivatives to show that with just a change of substituents this class of small molecules can show dramatic changes in their photophysical properties. The emission properties and ICT abilities of these molecules are compared with regards to various electron donating and withdrawing substituents. Substituents such as cyano and methoxycarbonyl groups do not induce any ICT character whereas substituents like aldehyde, N,N-dimethylamino and nitro groups cause appreciable ICT character in this class of molecules and their emission spectra extend almost throughout the whole visible region. The comparative ICT character was correlated with the results of electron density difference calculations. Computational studies show that the molecules are planar in their ground as well as excited states; except the nitro group containing molecule, which has an orthogonally twisted structure in the excited state. The emission properties of this molecule led to its inclusion into a class of nitroaromatics which shows maximum emission intensity in moderately polar solvents and the emission is quenched drastically by either decreasing or increasing solvent polarity. Fluorescence anisotropy studies show very good sensitivity of these compounds towards microviscosity of their immediate molecular environment. A white light emitting (WLE) gel was prepared using 4-(anthracen-9-ylethynyl)benzonitrile (AnPCN) and 4-(anthracen-9-ylethynyl)-N,N-dimethylaniline (AnPNMe2) by taking polyvinyl alcohol (PVA) as the gelator and the resulting gel exhibited very good CIE (0.31, 0.33) with CCT (6598 K) and CRI (87). As an example, the use of the gel was also demonstrated by applying it to a commercial UV LED which showed satisfactory results. AnPNMe2 was used to sense polar solvent vapors in TLC plates and Whatman paper due to its good solvatochromic behavior.

19.
Sci Total Environ ; 861: 160680, 2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36481148

RESUMEN

Real-time streamflow forecasting is essential to manage water resources effectively in a reservoir-regulated basin. However, forecasting becomes challenging without weather and upstream reservoir outflows forecasts in real-time. In this context, a novel hybrid approach is proposed in this study to forecast the streamflows and reservoir outflows in real-time. In this approach, the Explainable Machine Learning model is embedded with a conceptual reservoir module for forecasting streamflows using short-term weather forecasts. Long Short Term Memory (LSTM), a Machine Learning model, is used in this study to predict the streamflow, and the model's explainability is examined by Shapley additive explanations method (SHAP). Panchet reservoir catchment, which contains Tenughat and Konar reservoirs, is selected as a study area. The LSTM model performance is excellent in predicting the streamflows of Tenughat, Konar and Panchet catchments with NSE values of 0.93, 0.87, and 0.96, respectively. The SHAP method identified the high-impact variables as streamflows and precipitation of 1-day lag. In forecasting, bias-corrected Global Forecast System data is used with the LSTM model to forecast the streamflows in three catchments. The inflows are forecasted well up to a 3-day lead in Tenughat and Konar reservoirs with NSE values above 0.88 and 0.87, respectively. The reservoir module performance in forecasting Tenughat and Konar reservoirs' outflows with the inflow forecasts is also promising up to a 3-day lead with NSE values above 0.88 for both reservoirs. The inflows forecasting to Panchet reservoir with reservoirs' outflows as additional inputs is excellent up to 5-day lead (NSE = 0.96-0.88). However, the forecasting error increased from 77 m3/s to 134 m3/s with the lead time. This approach could provide an efficient way to reduce flood risks in the reservoir-regulated basin.


Asunto(s)
Aprendizaje Automático , Ríos , Recursos Hídricos , Tiempo (Meteorología) , Predicción
20.
F1000Res ; 12: 335, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38988644

RESUMEN

Background: Ashwagandha is a well-known Ayurvedic herb used for youthful vigor and wellbeing. This study investigated the effects of 600 mg standardized root extract (>5% withanolides) of Ashwagandha ( Withania somnifera) on muscle size, strength and cardiorespiratory endurance following resistance training. Methods: In this eight-week, parallel-group, multicenter, randomized, double-blind, placebo-controlled clinical study, 80 healthy male and female participants aged 18-45 years, who engaged in regular physical activity were randomly allocated in a 1:1 ratio to receive Ashwagandha (AG, n=40) 300 mg capsules twice daily for eight weeks, or identical placebo (PB, n=40). Seven (3 AG, 4 PB) participants were excluded due to poor compliance. All participants conducted eight-week resistance training. Study outcomes included muscle strength (1RM bench press and leg extension), muscle size (circumference of arm, chest and upper thigh) and cardio-respiratory endurance (VO 2max) assessed at baseline and at eight weeks. Analysis of covariance (ANCOVA) was used to estimate adjusted differences based on sex, BMI and chest circumference at baseline. Results: AG caused greater improvement in bench press (males: p = 0.0084; females: p = 0.0005), leg press (males: p = 0.0049; females: p = 0.018) and endurance (males: p <0.0001; females: p <0.0001) as compared to PB. Also, greater improvements in muscle girth for arm, chest and thigh were seen in both male and female participants with AG. No adverse events were reported in the study. Conclusions: Eight weeks of AG root extract supplementation along with resistance training is effective in improving muscle strength, growth and endurance in both male and female participants. AG root extract could be a safer, effective and low-cost alternative for athletes to improve muscle endurance.


Asunto(s)
Resistencia Física , Extractos Vegetales , Raíces de Plantas , Entrenamiento de Fuerza , Withania , Humanos , Masculino , Extractos Vegetales/farmacología , Femenino , Adulto , Método Doble Ciego , Resistencia Física/efectos de los fármacos , Adulto Joven , Estudios Prospectivos , Fuerza Muscular/efectos de los fármacos , Adolescente , Persona de Mediana Edad , Consumo de Oxígeno/efectos de los fármacos
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