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1.
Heliyon ; 10(10): e31230, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813160

RESUMO

Research for the development of noble metal-free electrodes for hydrogen evolution has blossomed in recent years. Transition metal carbides compounds, such as W2C, have been considered as a promising alternative to replace Pt-family metals as electrocatalysts towards hydrogen evolution reaction (HER). Moreover, hybridization of TMCs with graphene nanostructures has emerged as a reliable strategy for the preparation of compounds with high surface to volume ratio and abundant active sites. The present study focuses in the preparation of tungsten carbide/oxide compounds deposited in a three-dimensional vertical graphene nanowalls (VGNW) substrate via chemical vapor deposition, magnetron sputtering and thermal annealing processes. Structural and chemical characterization reveals the partial carburization and oxidation of the W film sputtered on the VGNWs, due to C and O migration from VGNWs towards W during the high temperature annealing process. Electrochemical characterization shows the enhanced performance of the nanostructured hybrid W2C/WOx on VGNW compound towards HER, when compared with planar W2C/WOx films. The W2C/WOx nanoparticles on VGNWs require an overpotential of -252 mV for the generation of 10 mA cm-2. Chronoamperometry tests in high overpotentials reveal the compounds stability while sustaining high currents, in the order of hundreds of mA. Post-chronoamperometry test XPS characterization unveils the formation of a W hydroxide layer which favours hydrogen evolution in acidic electrolytes. We aspire that the presented insights can be valuable for those working on the preparation of hybrid electrodes for electrochemical processes.

2.
Soa Chongsonyon Chongsin Uihak ; 35(2): 107-118, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38601106

RESUMO

Objectives: This study aims to extract and summarize the literature on the mental health status of patients with monkeypox. Methods: This review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using different databases and publishers such as Scopus, Sage, ScienceDirect, PubMed, BMJ, Wiley Online Library, Wolters Kluwer OVID-SP, and Google Scholar. The literature review was based on monkeypox and mental health. The year of publication was 2021-2023, during the monkeypox disease period. Data were extracted from opinions, editorials, empirical studies, and surveys. Results: Based on the literature related to the mental status of patients with monkeypox, the following themes and subthemes were identified: anxiety and depression, self-harm and suicidal tendencies, neuropsychiatric symptoms, mental health, social stigma, sex workers, vaccination, and stress-related diseases. Conclusion: A review of monkeypox virus infection studies reveals that 25%-50% of patients experience anxiety and depression due to isolation, boredom, and loneliness. Factors such as infected people, a lack of competence among healthcare professionals, and shame over physical symptoms exacerbate mental insults. The implications of society include increased self-harm, suicide, low productivity, fear of stigmatization, and transmission of infection.

3.
Chemosphere ; 355: 141745, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521100

RESUMO

The application of carbon nanoparticles (CNPs) and biochar in agriculture for improving plant health and soil quality and alleviating metal stress offers alternative approaches to meet the ever-increasing demand for food. However, poor understanding of their roles in improving crop production under Cu stress represents a significant obstacle to their wide application in agriculture. To clarify how CNPs and biochar affect corn (Zea mays L.) seed germination, seedling growth, plant health, and nutrient uptake under different Cu stress levels, soil-less Petri-dish and greenhouse soil-based bioassays were conducted. The results revealed that CNPs and biochar stimulated corn seed germination and seedling growth. Besides, they were effective in immobilizing Cu2+ sorption in sandy soil and alleviating Cu stress for plant growth, as shown by the increased plant height and dry biomass. The plant nutrient uptake efficiency (NUE) was significantly increased by CNPs, with a maximum increase of 63.1% for N and 63.3% for K at the highest Cu2+ stress level (400 mg Cu2+ L-1). In contrast, non-significant effects on NUE were observed with biochar treatments regardless of Cu stress levels. Interestingly, CNPs significantly increased plant uptake of Cu in the Petri dish test, while biochar inhibited plant uptake of Cu under both experimental conditions. Principle component analysis (PCA) and Pearson correlation analysis indicated that CNPs mitigated Cu stress mainly by elevating antioxidant enzyme activities, enhancing plant photochemical efficiency, and increasing plant uptake of N and K, while biochar was more likely to reduce bioavailability and uptake of Cu in the plant. These findings have great implications for the application of CNPs and biochar as plant growth stimulators and de-toxicity agents in agriculture.


Assuntos
Nanopartículas , Poluentes do Solo , Cobre/farmacologia , Cobre/análise , Zea mays , Carvão Vegetal/farmacologia , Solo , Plântula , Sementes , Poluentes do Solo/análise
4.
Nanomaterials (Basel) ; 13(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37764562

RESUMO

In recent years, vertical graphene nanowalls (VGNWs) have gained significant attention due to their exceptional properties, including their high specific surface area, excellent electrical conductivity, scalability, and compatibility with transition metal compounds. These attributes position VGNWs as a compelling choice for various applications, such as energy storage, catalysis, and sensing, driving interest in their integration into next-generation commercial graphene-based devices. Among the diverse graphene synthesis methods, plasma-enhanced chemical vapor deposition (PECVD) stands out for its ability to create large-scale graphene films and VGNWs on diverse substrates. However, despite progress in optimizing the growth conditions to achieve micrometer-sized graphene nanowalls, a comprehensive understanding of the underlying physicochemical mechanisms that govern nanostructure formation remains elusive. Specifically, a deeper exploration of nanometric-level phenomena like nucleation, carbon precursor adsorption, and adatom surface diffusion is crucial for gaining precise control over the growth process. Hydrogen's dual role as a co-catalyst and etchant in VGNW growth requires further investigation. This review aims to fill the knowledge gaps by investigating VGNW nucleation and growth using PECVD, with a focus on the impact of the temperature on the growth ratio and nucleation density across a broad temperature range. By providing insights into the PECVD process, this review aims to optimize the growth conditions for tailoring VGNW properties, facilitating applications in the fields of energy storage, catalysis, and sensing.

5.
Plant Physiol Biochem ; 196: 859-867, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36871496

RESUMO

Chromium is a highly toxic heavy metal. High concentrations of Cr (III) can affect metabolic processes in plants, resulting in different morphological, physiological, and biochemical defects. Agricultural practices such as sewage irrigation, over-fertilization, and sewage sludge application contribute significantly to Cr contamination. It can reduce the growth of plants by affecting the activity of antioxidant enzymes. The materials in nano form play an important role in nano-remediation and heavy metals absorption due to their high surface area and micropores. This research was conducted to study the potential of foliar application of nanobiochar/nBC (100 mg/L-1 and 150 mg/L-1) for mitigation of Cr (III) stress (200 mg/kg and 300 mg/kg) in black cumin (Nigella sativa) plants. The results showed that increased Cr stress (300 mg/kg) decreased the plant growth parameters, chlorophyll content, total soluble sugars, and proteins. However, increased the level of hydrogen peroxide (H2O2) and malondialdehyde acetate (MDA) as a result of the activity of antioxidant enzymes (Catalase, Superoxide dismutase, peroxidase dismutase, and ascorbic peroxidase) increased in Nigella sativa seedlings. Foliar application of the nBC (100 mg/L-1) increased plant growth parameters, chlorophyll content, and osmoprotectants, while decreasing the levels of oxidative stress markers (H2O2 and MDA). Furthermore, with the application of nBC, the antioxidant enzyme activity considerably improved. Improved antioxidant activity shows that nBC helped to decrease oxidative stress, which in return improved the growth of Nigella sativa seedlings. Overall, present study findings concluded that foliar application of nBC in Nigella sativa seedlings improved growth, chlorophyll, and antioxidant enzymes. The nBC treatment of 100 mg/L-1 showed better results compared to 150 mg/L-1 under chromium stress.


Assuntos
Nigella sativa , Poluentes do Solo , Antioxidantes/metabolismo , Nigella sativa/metabolismo , Solo , Peróxido de Hidrogênio/metabolismo , Esgotos , Estresse Oxidativo , Clorofila/metabolismo , Peroxidases , Cromo/toxicidade , Poluentes do Solo/toxicidade
6.
PLoS One ; 17(2): e0263194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35192615

RESUMO

Salt stress is the major risk to the seed germination and plant growth via affecting physiological and biochemical activities in plants. Zinc nanoparticles (ZnNPs) are emerged as a key agent in regulating the tolerance mechanism in plants under environmental stresses. However, the tolerance mechanisms which are regulated by ZnNPs in plants are still not fully understood. Therefore, the observation was planned to explore the role of ZnNPs (applied as priming and foliar) in reducing the harmful influence of sodium chloride (NaCl) stress on the development of spinach (Spinacia oleracea L.) plants. Varying concentrations of ZnNPs (0.1%, 0.2% & 0.3%) were employed to the spinach as seed priming and foliar, under control as well as salt stress environment. The alleviation of stress was observed in ZnNPs-applied spinach plants grown under salt stress, with a reduced rise in the concentration hydrogen peroxide, melondialdehyde and anthocyanin contents. A clear decline in soluble proteins, chlorophyll contents, ascorbic acid, sugars, and total phenolic contents was observed in stressed conditions. Exogenous ZnNPs suppressed the NaCl generated reduction in biochemical traits, and progress of spinach plants. However, ZnNPs spray at 0.3% followed by priming was the most prominent treatment in the accumulation of osmolytes and the production of antioxidant molecules in plants.


Assuntos
Nanopartículas Metálicas/administração & dosagem , Substâncias Protetoras/farmacologia , Estresse Salino/fisiologia , Sementes/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Spinacia oleracea/efeitos dos fármacos , Zinco/farmacologia , Partículas e Gotas Aerossolizadas/administração & dosagem , Antocianinas/metabolismo , Ácido Ascórbico/metabolismo , Clorofila/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Nanopartículas Metálicas/química , Fenóis/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Spinacia oleracea/crescimento & desenvolvimento , Spinacia oleracea/metabolismo
7.
Front Plant Sci ; 12: 627107, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777067

RESUMO

Cotton is an important fiber and cash crop. Extreme water scarceness affects the growth, quality, and productivity of cotton. Water shortage has threatened the future scenario for cotton growers, so it is imperative to devise a solution to this problem. In this research, we have tried to machinate a solution for it. 23 genotypes have been screened out against drought tolerance at the seedling stage by evaluating the morphological, physiological, and biochemical traits in a triplicate completely randomized design plot experiment with two water regimes [50 and 100% field capacity]. Genotypic differences for all the morphological and physiological traits revealed highly significant differences except transpiration rate (TR). Moreover, the interaction between genotype and water regime (G × W) was highly significant for root length (RL, 5.163), shoot length (SL, 11.751), excised leaf water loss (ELWL, 0.041), and stomatal conductance (SC, 7.406). A positively strong correlation was found in TR with relative water content (RWC; 0.510) and SC (0.584) and RWC with photosynthesis (0.452) under drought conditions. A negative correlation was found in SC with SL (-0.428) and photosynthesis (-0.446). Traits like RL, SL, SC, photosynthesis, proline, catalase, and malondialdehyde were visible indicators, which can differentiate drought-tolerant genotypes from the susceptible ones. A wide range of diversity was found in all the morpho-physiological traits with the cumulative variance of four principal components (PCs) 83.09% and three PCs 73.41% under normal and water-stressed conditions, respectively, as per the principal component analysis. Hence, selection criteria can be established on the aforementioned traits for the development of drought-tolerant cultivars. Moreover, it was found that out of 23 experimental varieties, NIAB-135, NIAB-512, and CIM-554 could be used to devise breeding strategies for improving drought tolerance in cotton.

8.
Plant Physiol Biochem ; 155: 147-160, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32758996

RESUMO

Nitric oxide (NO) is a key signaling molecule that instigates significant changes in plant metabolic processes and promotes tolerance against various environmental stresses including drought. In this study, we focused on NO-mediated physiological mechanisms and enzymatic activities that influence the nutrient concentrations and yield in maize under drought stress. The drought-tolerant (NK-8711) and sensitive (P-1574) maize hybrids were sown in lysimeter tanks and two levels of water stress (well-watered at100% field capacity and drought stress at 60% field capacity) were applied at three-leaves stage of maize. Foliar treatment of sodium nitroprusside (SNP), the donor of NO was applied at the cob development stage. The results showed that the foliar spray of NO regulated water relations by increasing proline content and improved drought tolerance in water stressed maize plants. In addition, it stimulated the activity of antioxidative enzymes which reduced the production of free radicals and lipid peroxidation. The activities of nitrate assimilation enzymes were considerably increased by NO spray which, in turn, increased nutrient accumulation and yield in maize under water deficit conditions. These results acknowledge the importance of NO as a stress-signaling molecule that positively regulates defense mechanisms in maize to withstand water-limited conditions.


Assuntos
Secas , Óxido Nítrico/farmacologia , Estresse Fisiológico , Zea mays/enzimologia , Nitroprussiato/farmacologia , Folhas de Planta , Água
9.
J Inequal Appl ; 2018(1): 119, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29805239

RESUMO

In this paper we prove the Hadamard and the Fejér-Hadamard inequalities for the extended generalized fractional integral operator involving the extended generalized Mittag-Leffler function. The extended generalized Mittag-Leffler function includes many known special functions. We have several such inequalities corresponding to special cases of the extended generalized Mittag-Leffler function. Also there we note the known results that can be obtained.

10.
J Inequal Appl ; 2017(1): 121, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28603400

RESUMO

Fractional inequalities are useful in establishing the uniqueness of solution for partial differential equations of fractional order. Also they provide upper and lower bounds for solutions of fractional boundary value problems. In this paper we obtain some general integral inequalities containing generalized Mittag-Leffler function and some already known integral inequalities have been produced as special cases.

11.
Ecotoxicol Environ Saf ; 122: 528-36, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26426697

RESUMO

Increasing concentration of Cd in soil is of great concern due to risk of its entry into food chain. Zinc (Zn) being antagonist to Cd is an important micronutrient to ameliorate its toxic effects on plants and to limit its entry into food chain. A pot experiment was conducted using Cd contaminated soil (30 mg Cd kg(-1) soil as 3CdSO4 · 8H2O) to investigate the effect of soil and foliar applied Zn on physiological response and Cd concentration in wheat. In soil, Zn was applied at 15 and 30 mg Zn kg(-1) soil as zinc sulfate (ZnSO4 · 7H2O). For foliar applications, 3 and 6 g L(-1) ZnSO4 solution was sprayed on completing eight weeks of growth. Results indicated that Zn application could effectively improve physiological performance and mineral content of wheat grown on Cd contaminated soils. Among different Zn fertilization treatments, foliar application of 3 g L(-1) ZnSO4 solution recorded the maximum soluble proteins and the minimum grain-Cd concentration. Soil application of ZnSO4 or foliar application at 6 g L(-1) did not affect Cd concentration in grains. Zinc application through both the methods significantly increased phosphorus (P), potassium (K) and Zn concentrations in shoots. Concentration of P and K in grains showed positive relationship with that of Zn. In crux, present study suggests that foliar application of Zn at booting stage in a suitable concentration (3 g L(-1) ZnSO4 solution) can effectively ameliorate the adverse effects of Cd and decrease grain-Cd of wheat grown in Cd contaminated soil.


Assuntos
Cádmio/toxicidade , Grão Comestível/crescimento & desenvolvimento , Minerais/metabolismo , Poluentes do Solo/toxicidade , Triticum/crescimento & desenvolvimento , Zinco/farmacologia , Biomassa , Cádmio/análise , Cádmio/metabolismo , Clorofila/metabolismo , Grão Comestível/química , Grão Comestível/metabolismo , Modelos Teóricos , Proteínas de Plantas/metabolismo , Poluentes do Solo/metabolismo , Triticum/química , Triticum/metabolismo , Zinco/metabolismo , Sulfato de Zinco/metabolismo , Sulfato de Zinco/farmacologia
12.
J Sci Food Agric ; 90(6): 925-37, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20355131

RESUMO

Cadmium (Cd) is a highly toxic heavy metal for both plants and animals. The presence of Cd in agricultural soils is of great concern regarding its entry into the food chain. Cadmium enters into the soil-plant environment mainly through anthropogenic activities. Compounds of Cd are more soluble than other heavy metals, so it is more available and readily taken up by plants and accumulates in different edible plant parts through which it enters the food chain. A number of approaches are being used to minimize the entry of Cd into the food chain. Proper plant nutrition is one of the good strategies to alleviate the damaging effects of Cd on plants and to avoid its entry into the food chain. Plant nutrients play a very important role in developing plant tolerance to Cd toxicity and thus, low Cd accumulation in different plant parts. In this report, the role of some macronutrients (nitrogen, phosphorus, sulfur and calcium), micronutrients (zinc, iron and manganese), and silicon (a beneficial nutrient) has been discussed in detail as to how these nutrients play their role in decreasing Cd uptake and accumulation in crop plants.


Assuntos
Cádmio/metabolismo , Produtos Agrícolas/metabolismo , Micronutrientes/farmacologia , Minerais/farmacologia , Nitrogênio/farmacologia , Transporte Biológico , Cádmio/toxicidade , Cálcio/farmacologia , Fósforo/farmacologia , Estruturas Vegetais , Solo , Solubilidade , Enxofre/farmacologia
13.
J Coll Physicians Surg Pak ; 15(4): 218-20, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15857594

RESUMO

OBJECTIVE: To determine the rate of locoregional recurrence, disease-free interval, site and pattern of locoregional recurrence and the significance of different factors for predicting locoregional recurrence in patients with stage II and III carcinoma breast. DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Surgical Unit-1, Jinnah Hospital, Lahore from September 2001 to December 2002. PATIENTS AND METHODS: Criteria for including patients in this study was female patients with stage II and III carcinoma breast who presented in our unit from 1995-2002 and underwent surgical (modified radical mastectomy, simple mastectomy with axillary sampling) and non-surgical (chemotherapy, radiotherapy, hormonal therapy) treatment of carcinoma breast. Record of 98 patients was evaluated for rate of locoregional recurrence, disease-free interval, site and pattern of locoregional recurrence and different clinical factors like stage of carcinoma, tumour size, lymph node status and histopathology were assessed for association with locoregional recurrence. RESULTS: After a mean follow-up of 3.5 years, 17 patients developed locoregional recurrence. Mean disease free interval in stage II was 30 months and only 9.5 months in stage III. Lymph node positivity was associated with locoregional recurrence (p-value<0.05). Chest wall was commonest site of recurrence (73%). Single spot recurrence was common in stage II whereas multiple spot recurrence and field change was more common in stage III. Addition of radiotherapy to surgery decreased the locoregional recurrence but chemotherapy had no significant effect on prevention of locoregional recurrence. CONCLUSION: In this series 17.34 % patients developed locoregional recurrence for mean follow-up duration of 3.5 years. Mean disease-free interval was 20.52 months. Lymph node involvement had significant correlation with LRR.


Assuntos
Neoplasias da Mama/terapia , Carcinoma/terapia , Recidiva Local de Neoplasia/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Carcinoma/epidemiologia , Carcinoma/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos
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