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1.
J Biotechnol ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38825191

RESUMEN

Solanum xanthocarpum fruits are used in the treatment of cough, fever, and heart disorders. It possesses antipyretic, hypotensive, antiasthmatic, aphrodisiac and antianaphylactic properties. In the present study, 24 elicitors (both biotic and abiotic) were used to enhance the production of glycoalkaloids in cell cultures of S. xanthocarpum. Four concentrations of elicitors were added into the MS culture medium. The maximum accumulation (5.56-fold higher than control) of demissidine was induced by sodium nitroprusside at 50mM concentration whereas the highest growth of cell biomass (4.51-fold higher than control) stimulated by systemin at 30mM concentration. A total of 17 genes of biosynthetic pathways of glycoalkaloids were characterized from the cells of S. xanthocarpum. The greater accumulation of demissidine was confirmed with the expression analysis of 11 key biosynthetic pathway enzymes e.g., acetoacetic-CoA thiolase, 3- hydroxy 3-methyl glutaryl synthase, ß-hydroxy ß-methylglutaryl CoA reductase, mevalonate kinase, farnesyl diphosphate synthase, squalene synthase, squalene epoxidase, squalene-2,3- epoxide cyclase, cycloartenol synthase, UDP-glucose: solanidine glucosyltransferase and UDP-rhamnose: solanidine rhamno-galactosyl transferase. The maximum expression levels of UDP-rhamnose: solanidine rhamno-galactosyl transferase gene was recorded in this study.

2.
Heliyon ; 10(7): e28758, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38576553

RESUMEN

Mango is a commercial fruit crop of India that suffers huge postharvest losses every year. The application of biocontrol agents (BCAs) bears a vast potential for managing the same, which is yet to be exploited to its fullest extent. Hence, studies were conducted for BCAs application of Debaryomyces hansenii, Bacillus subtilis and Pseudomonas fluorescens strains on mango fruit under in-vitro, in-vivo conditions to know the efficacy of these BCAs on the postharvest pathogen, shelf life and quality retention of mango fruit. The 'poisoned food technique' was attempted for in-vitro studies. For the in-vivo studies, fruit of the commercial cultivar 'Amrapali' were un-inoculated and pre-inoculated with major postharvest pathogens (anthracnose: Colletotrichum gloeosporioides and stem-end rot: Botryodiplodia theobromae) were treated with BCA, followed by ambient storage at (24 ± 4 °C, 75 ± 5 % RH). From the results, it has been observed that under in vitro studies, BCA Debaryomyces hansenii (Strain: KP006) and Bacillus subtilis (Strain: BJ0011) at the treatment level 108 CFU mL-1 while, the Pseudomonas fluorescens at 109 CFU mL-1 (Strain: BE0001) were significantly effective for pathogen inhibition. However, under the in vivo studies, the BCA Debaryomyces hansenii (Strain: KP006) at 108 CFU mL-1 treatment level was found to significantly reduce the pathogen's decay incidence while positively influencing the shelf life and biochemical (quality) attributes. This treatment increased the storage life of mango fruit by more than three days over control fruit. Therefore, BCA Debaryomyces hansenii (Strain: KP006) at 108 CFU mL-1 can be used to control the postharvest pathological loss of mango fruit without affecting its internal quality.

3.
Cancer Lett ; 586: 216666, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38311053

RESUMEN

Glioblastoma (GBM) is a highly aggressive and treatment-resistant brain tumor, necessitating novel therapeutic strategies. In this study, we present a mechanistic breakthrough by designing and evaluating a series of abiraterone-installed hydroxamic acids as potential dual inhibitors of CYP17A1 and HDAC6 for GBM treatment. We established the correlation of CYP17A1/HDAC6 overexpression with tumor recurrence and temozolomide resistance in GBM patients. Compound 12, a dual inhibitor, demonstrated significant anti-GBM activity in vitro, particularly against TMZ-resistant cell lines. Mechanistically, compound 12 induced apoptosis, suppressed recurrence-associated genes, induced oxidative stress and initiated DNA damage response. Furthermore, molecular modeling studies confirmed its potent inhibitory activity against CYP17A1 and HDAC6. In vivo studies revealed that compound 12 effectively suppressed tumor growth in xenograft and orthotopic mouse models without inducing significant adverse effects. These findings highlight the potential of dual CYP17A1 and HDAC6 inhibition as a promising strategy for overcoming treatment resistance in GBM and offer new hope for improved therapeutic outcomes.


Asunto(s)
Androstenos , Neoplasias Encefálicas , Glioblastoma , Esteroide 17-alfa-Hidroxilasa , Animales , Humanos , Ratones , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Daño del ADN , Resistencia a Antineoplásicos , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/patología , Histona Desacetilasa 6/genética , Ácidos Hidroxámicos/farmacología , Ácidos Hidroxámicos/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Estrés Oxidativo , Temozolomida/farmacología , Temozolomida/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Arch Virol ; 169(3): 51, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38374459

RESUMEN

In this study, we investigated and confirmed natural lumpy skin disease virus (LSDV) infection in Himalayan yaks (Bos grunniens) in Himachal Pradesh, India, based on clinical manifestations and results of genome detection, antibody detection, virus isolation, and nucleotide sequencing. Subsequent phylogenetic analysis based on complete GPCR, RPO30, and EEV gene sequences revealed that the LSDV isolates from these yaks and local cattle belonged to LSDV subcluster 1.2.1 rather than the dominant subcluster 1.2.2, which is currently circulating in India, suggesting a separate recent introduction. This is the first report of natural LSDV infection in yaks in India, expanding the known host range of LSDV. Further investigations are needed to assess the impact of LSDV infection in yaks.


Asunto(s)
Virus de la Dermatosis Nodular Contagiosa , Animales , Bovinos , Filogenia , Secuencia de Bases , India/epidemiología , Brotes de Enfermedades/veterinaria
5.
JCI Insight ; 9(3)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38127456

RESUMEN

Despite clinical use of immunosuppressive agents, the immunopathogenesis of minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) remains unclear. Src homology 3-binding protein 2 (SH3BP2), a scaffold protein, forms an immune signaling complex (signalosome) with 17 other proteins, including phospholipase Cγ2 (PLCγ2) and Rho-guanine nucleotide exchange factor VAV2 (VAV2). Bioinformatic analysis of human glomerular transcriptome (Nephrotic Syndrome Study Network cohort) revealed upregulated SH3BP2 in MCD and FSGS. The SH3BP2 signalosome score and downstream MyD88, TRIF, and NFATc1 were significantly upregulated in MCD and FSGS. Immune pathway activation scores for Toll-like receptors, cytokine-cytokine receptor, and NOD-like receptors were increased in FSGS. Lower SH3BP2 signalosome score was associated with MCD, higher estimated glomerular filtration rate, and remission. Further work using Sh3bp2KI/KI transgenic mice with a gain-in-function mutation showed ~6-fold and ~25-fold increases in albuminuria at 4 and 12 weeks, respectively. Decreased serum albumin and unchanged serum creatinine were observed at 12 weeks. Sh3bp2KI/KI kidney morphology appeared normal except for increased mesangial cellularity and patchy foot process fusion without electron-dense deposits. SH3BP2 co-immunoprecipitated with PLCγ2 and VAV2 in human podocytes, underscoring the importance of SH3BP2 in immune activation. SH3BP2 and its binding partners may determine the immune activation pathways resulting in podocyte injury leading to loss of the glomerular filtration barrier.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria , Nefrosis Lipoidea , Síndrome Nefrótico , Animales , Humanos , Ratones , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Glomeruloesclerosis Focal y Segmentaria/genética , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Riñón/patología , Glomérulos Renales/patología , Ratones Transgénicos , Nefrosis Lipoidea/patología , Síndrome Nefrótico/metabolismo , Fosfolipasa C gamma/genética , Fosfolipasa C gamma/metabolismo
6.
Sci Rep ; 13(1): 19853, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37963906

RESUMEN

Considering the major source of plant-derived low/non-calorie steviol glycosides (SGs), comprehensive physiological, biochemical, and deep transcriptional investigations were conducted to explicit deeper insight into multiple abiotic stress responses in Stevia rebaudiana. The physiological indicators including photosynthesis, chlorophyll, relative water content, shoot growth, electrolyte leakage, and SG biosynthesis were negatively impacted under drought (DS), followed by salinity (SS) and waterlogging (WS). Global transcriptional analysis revealed significant upregulated expression of the genes encoding for ROS detoxification (GST, SOD, APX, glutathione peroxidase), osmotic adjustment (alpha-trehalose-phosphate and S-adenosylmethionine decarboxylase), ion transporters (CAX, NHX, CNGS, VPPase, VATPase), water channel (PIP1, TIP) and abiotic stress-responsive candidate genes (LEA, HSPs, and Dehydrins) regulating abiotic stress response in S. rebaudiana. These inferences were complemented with predicted interactome network that revealed regulation of energy metabolism by key stress-responsive genes (GST, HKT1, MAPKs, P5CSs, PIP), transcription factors (HSFA2, DREB1A, DREB2A), and abiotic stress responsive pathways (ABA, ethylene, ion stress). This is the first detailed study to comprehend the molecular regulation of stress response and their interplay under DS, SS, and WS. The key genes and regulators can be functionally validated, and will facilitate targeted gene editing for genetic improvement of crop sustainability under changing environmental conditions in S. rebaudiana.


Asunto(s)
Diterpenos de Tipo Kaurano , Stevia , Stevia/genética , Stevia/metabolismo , Diterpenos de Tipo Kaurano/metabolismo , Fotosíntesis , Estrés Fisiológico/genética , Hojas de la Planta/metabolismo , Regulación de la Expresión Génica de las Plantas
7.
Curr Drug Targets ; 24(15): 1184-1208, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37946353

RESUMEN

Proteolysis Targeting Chimeras (PROTACs) technology has emerged as a promising strategy for the treatment of undruggable therapeutic targets. Researchers have invested a great effort in developing druggable PROTACs; however, the problems associated with PROTACs, including poor solubility, metabolic stability, cell permeability, and pharmacokinetic profile, restrict their clinical utility. Thus, there is a pressing need to expand the size of the armory of PROTACs which will escalate the chances of pinpointing new PROTACs with optimum pharmacokinetic and pharmacodynamics properties. N- heterocycle is a class of organic frameworks that have been widely explored to construct new and novel PROTACs. This review provides an overview of recent efforts of medicinal chemists to develop N-heterocycle-based PROTACs as effective cancer therapeutics. Specifically, the recent endeavors centred on the discovery of PROTACs have been delved into various classes based on the E3 ligase they target (MDM2, IAP, CRBN, and other E3 ligases). Mechanistic insights revealed during the biological assessment of recently furnished Nheterocyclic- based PROTACs constructed via the utilization of ligands for various E3 ligases have been discussed.


Asunto(s)
Quimera Dirigida a la Proteólisis , Ubiquitina-Proteína Ligasas , Humanos , Permeabilidad , Solubilidad , Ligandos
8.
J Enzyme Inhib Med Chem ; 38(1): 2276665, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37919954

RESUMEN

Structural tailoring of the flavone framework (position 7) via organopalladium-catalyzed C-C bond formation was attempted in this study. The impact of substituents with varied electronic effects (phenyl ring, position 2 of the benzopyran scaffold) on the antitumor properties was also assessed. Resultantly, the efforts yielded a furyl arm bearing benzopyran possessing a 4-fluoro phenyl ring (position 2) (14) that manifested a magnificent antitumor profile against the Ishikawa cell lines mediated through dual inhibition of PARP and tubulin [(IC50 (PARP1) = 74 nM, IC50 (PARP2) = 109 nM) and tubulin (IC50 = 1.4 µM)]. Further investigations confirmed the ability of 14 to induce apoptosis as well as autophagy and cause cell cycle arrest at the G2/M phase. Overall, the outcome of the study culminated in a tractable dual PARP-tubulin inhibitor endowed with an impressive activity profile against endometrial cancer.


Asunto(s)
Antineoplásicos , Neoplasias Endometriales , Flavonas , Humanos , Femenino , Moduladores de Tubulina/farmacología , Moduladores de Tubulina/química , Tubulina (Proteína)/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Antineoplásicos/farmacología , Antineoplásicos/química , Apoptosis , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/patología , Flavonas/farmacología , Benzopiranos , Proliferación Celular
9.
Front Med (Lausanne) ; 10: 1213320, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37663654

RESUMEN

Mast cells are important components of the immune system, and they perform pro-inflammatory as well as anti-inflammatory roles in the complex process of immune regulation in health and disease. Because of their strategic perivascular localization, sensitivity and adaptability to the microenvironment, and ability to release a variety of preformed and newly synthesized effector molecules, mast cells perform unique functions in almost all organs. Additionally, Mast cells express a wide range of surface and cytoplasmic receptors which enable them to respond to a variety of cytokines, chemicals, and pathogens. The mast cell's role as a cellular interface between external and internal environments as well as between vasculature and tissues is critical for protection and repair. Mast cell interactions with different immune and nonimmune cells through secreted inflammatory mediators may also turn in favor of disease promoting agents. First and forefront, mast cells are well recognized for their multifaceted functions in allergic diseases. Reciprocal communication between mast cells and endothelial cells in the presence of bacterial toxins in chronic/sub-clinical infections induce persistent vascular inflammation. We have shown that mast cell proteases and histamine induce endothelial inflammatory responses that are synergistically amplified by bacterial toxins. Mast cells have been shown to exacerbate vascular changes in normal states as well as in chronic or subclinical infections, particularly among cigarette smokers. Furthermore, a potential role of mast cells in SARS-CoV-2-induced dysfunction of the capillary-alveolar interface adds to the growing understanding of mast cells in viral infections. The interaction between mast cells and microglial cells in the brain further highlights their significance in neuroinflammation. This review highlights the significant role of mast cells as the interface that acts as sensor and early responder through interactions with cells in systemic organs and the nervous system.

10.
J Occup Health ; 65(1): e12421, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664983

RESUMEN

OBJECTIVE: Dengue fever is a significant public health problem in Nepal, and police personnel are considered to play a crucial role in preventing and controlling dengue fever. This study aimed to assess the factors that influence the knowledge, attitudes, and practices of police personnel toward dengue in Kathmandu, Nepal. METHODS: The study design was a descriptive cross-sectional study among 422 police personnel, where data were collected using self-administered questionnaires. Bi-variate analysis and multivariate analysis were used to examine the association between sociodemographic factors and environmental factors with knowledge, attitude, and practices of dengue. RESULTS: The study found that the knowledge, attitude, and practice toward dengue prevention was 58%, 46%, and 75%, respectively. The study found that family history of dengue (AOR = 2.78, 95% CI = 1.38-5.6), owning bed nets (AOR = 2.13, 95% CI = 1.04-4.35) and having covered water storage containers (AOR = 2.99, 95% CI = 1.74-5.13) were associated with higher odds of knowledge on dengue. Having family history of dengue (AOR = 2.45, 95% CI = 1.24-4.87) and the presence of broken glasses or discarded plastic bottles in the house (AOR = 2.07, 95% CI = 1.93-5.36) were associated with attitude on dengue. Knowledge on dengue was associated with higher odds of attitude (AOR = 3.3, 95% CI = 2.09-5.36) and practices (AOR = 3.21, 95% CI = 1.93, 5.36). CONCLUSION: The study identified specific factors associated with knowledge, attitude, and practices toward dengue prevention. The study concluded that regular training and awareness-raising activities are needed to improve their knowledge, attitudes, and practices toward dengue.


Asunto(s)
Dengue , Policia , Humanos , Estudios Transversales , Nepal/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Encuestas y Cuestionarios , Dengue/epidemiología , Dengue/prevención & control
11.
Front Plant Sci ; 14: 1186250, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37575914

RESUMEN

Stand biomass models can be used as basic decision-making tools in forest management planning. The Moso bamboo (Phyllostachys pubescens) forest, a major forest system in tropical and subtropical regions, represents a substantial carbon sink, slowing down the rise of greenhouse gas concentrations in the earth's atmosphere. Bamboo stand biomass models are important for the assessment of the contribution of carbon to the terrestrial ecosystem. We constructed a stand biomass model for Moso bamboo using destructively sampled data from 45 sample plots that were located across the Yixing state-owned farm in Jiangsu Province, China. Among several bamboo stand variables used as predictors in the stand biomass models, mean diameter at breast height (MDBH), mean height (MH), and canopy density (CD) of bamboo contributed significantly to the model. To increase the model's accuracy, we introduced the effects of bamboo forest block as a random effect into the model through mixed-effects modeling. The mixed-effects model described a large part of stand biomass variation (R2 = 0.6987), significantly higher than that of the ordinary least squares regression model (R2 = 0.5748). Our results show an increased bamboo stand biomass with increasing MH and CD, confirming our model's biological logic. The proposed stand biomass model may have important management implications; for example, it can be combined with other bamboo models to estimate bamboo canopy biomass, carbon sequestration, and bamboo biomass at different growth stages.

12.
Sci Rep ; 13(1): 13673, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37608034

RESUMEN

Microclimate ecology is attracting renewed attention because of its fundamental importance in understanding how organisms respond to climate change. Many hot issues can be investigated in desert ecosystems, including the relationship between species distribution and environmental gradients (e.g., elevation, slope, topographic convergence index, and solar insolation). Species Distribution Models (SDMs) can be used to understand these relationships. We used data acquired from the important desert plant Nitraria tangutorum Bobr. communities and desert topographic factors extracted from LiDAR (Light Detection and Ranging) data of one square kilometer in the inner Mongolia region of China to develop SDMs. We evaluated the performance of SDMs developed with a variety of both the parametric and nonparametric algorithms (Bioclimatic Modelling (BIOCLIM), Domain, Mahalanobi, Generalized Linear Model, Generalized Additive Model, Random Forest (RF), and Support Vector Machine). The area under the receiver operating characteristic curve was used to evaluate these algorithms. The SDMs developed with RF showed the best performance based on the area under curve (0.7733). We also produced the Nitraria tangutorum Bobr. distribution maps with the best SDM and suitable habitat area of the Domain model. Based on the suitability map, we conclude that Nitraria tangutorum Bobr. is more suited to southern part with 0-20 degree slopes at an elevation of approximately 1010 m. This is the first attempt of modelling the effects of topographic heterogeneity on the desert species distribution on a small scale. The presented SDMs can have important applications for predicting species distribution and will be useful for preparing conservation and management strategies for desert ecosystems on a small scale.


Asunto(s)
Ecosistema , Magnoliopsida , Algoritmos , China , Cambio Climático , Ecología
14.
Indian Pediatr ; 60(10): 843-854, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37179471

RESUMEN

JUSTIFICATION: The transgender community has been long stigmatized, and discriminated against, and faces numerous mental and physical problems. Certain indicators of transgender personality appear during childhood and more often before puberty begins. This puts the onus on Pediatricians to identify and offer evidence-based care for their benefit. There is an urgent and deep-felt need to understand the medical, legal, and social aspects of the care of transgender children. Hence, Adolescent Health Academy decided to release a statement on the care of transgender children, adolescents, and youth. OBJECTIVES: To review the existing international and national guidelines and recommendations to formulate a statement for the Pediatricians on (a) terminologies and definitions; (b) legal status in India; and (c) implications for pediatric practice. PROCESS: A task force was convened by the Adolescent Health Academy as the writing committee to draft the guidelines. These were approved by all the members of the task force and the Executive Board of Adolescent Health Academy (2022). RECOMMENDATIONS: Gender identity develops in childhood and adolescence as a feeling of self, and it should be respected to mitigate gender dysphoria. The law permits transgenders the right of self-affirmation and it upholds their dignity in society. The transgender community is prone to victimization, and prejudice leading to a high risk of substance abuse, suicidal ideation, and mental health issues. Pediatricians are the primary care providers of children and adolescents including those with gender incongruence, so they should be abridged with gender-affirmative practices. Gender-affirmative care involves pubertal suppression, hormonal therapy, and surgery which should be done in conjugation with the social transition, by a gender-affirmative care team.

15.
Artículo en Inglés | MEDLINE | ID: mdl-37033416

RESUMEN

Overactivated NLRP3 inflammasome has been shown to associate with an increasing number of disease conditions. Activation of the NLRP3 inflammasome results in caspase-1-catalyzed formation of active pro-inflammatory cytokines (IL-1ß and IL-18) resulting in pyroptosis. The multi-protein composition of the NLRP3 inflammasome and its sensitivity to several damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs) make this extensively studied inflammasome an attractive target to treat chronic conditions. However, none of the known NLRP3 inhibitors has been approved for clinical use. Sulfonylurea and covalent inhibitors with electrophilic warhead (Michael acceptor) are among the prominent classes of compounds explored for their NLRP3 inhibitory effects. Chalcone, a small molecule with α, ß unsaturated carbonyl group (Michael acceptor), has also been studied as a promising scaffold for the development of NLRP3 inhibitors. Low molecular weight, easy to manipulate lipophilicity and cost-effectiveness have attracted many to use chalcone scaffold for drug development. In this review, we highlight chalcone derivatives with NLRP3 inflammasome inhibitory activities. Recent developments and potential new directions summarized here will, hopefully, serve as valuable perspectives for investigators including medicinal chemists and drug discovery researchers to utilize chalcone as a scaffold for developing novel NLRP3 inflammasome inhibitors.

16.
Front Plant Sci ; 14: 1095126, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063221

RESUMEN

Height to crown base (HCB) is an important predictor variable for forest growth and yield models and is of great significance for bamboo stem utilization. However, existing HCB models built so far on the hierarchically structured data are for arbor forests, and not applied to bamboo forests. Based on the fitting of data acquired from 38 temporary sample plots of Phyllostachys edulis forests in Yixing, Jiangsu Province, we selected the best HCB model (logistic model) from among six basic models and extended it by integrating predictor variables, which involved evaluating the impact of 13 variables on HCB. Block- and sample plot-level random effects were introduced to the extended model to account for nested data structures through mixed-effects modeling. The results showed that bamboo height, diameter at breast height, total basal area of all bamboo individuals with a diameter larger than that of the subject bamboo, and canopy density contributed significantly more to variation in HCB than other variables did. Introducing two-level random effects resulted in a significant improvement in the accuracy of the model. Different sampling strategies were evaluated for response calibration (model localization), and the optimal strategy was identified. The prediction accuracy of the HCB model was substantially improved, with an increase in the number of bamboo samples in the calibration. Based on our findings, we recommend the use of four randomly selected bamboo individuals per sample to provide a compromise between measurement cost, model use efficiency, and prediction accuracy.

17.
Heliyon ; 9(3): e13865, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36873537

RESUMEN

BN50/NiO50 and Au-loaded BN50/NiO50 nanocomposite films were separately fabricated on the glass substrates for carrier transport and photoconductivity properties. X-ray diffraction pattern of the films show the hexagonal structure of BN and presence of defect states by Nelson Riley factor analysis. Morphological images show spherical shaped particles with highly porous structure. The incorporation of NiO may hindered growth of BN layers and resulted in spherical particles. Temperature-dependent conductivity describes semiconductor transport behaviour for deposited nanocomposite films. Thermal activation conduction with low activation energy (∼0.308 eV) may be responsible for the resulting conductivity. Further, the light intensity dependent photoelectrical properties of BN50/NiO50 and Au-loaded BN50/NiO50 nanocomposites have been explored. The effect of Au nanoparticles loading on enhanced photo-conductivities (∼22% increase) than bare nanocomposite film has been elaborated by proposed mechanism. This study provided the insightful information for carrier transport and photoconductivity of BN-based nanocomposites.

18.
Front Plant Sci ; 14: 1139448, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36909393

RESUMEN

Bamboo crown width (CW) is a reliable index for evaluating growth, yield, health and vitality of bamboo, and light capture ability and carbon fixation efficiency of bamboo forests. Based on statistical results produced from fitting the eight basic growth functions using data from 1374 Phyllostachys pubescens in Yixing, Jiangsu Province, China, this study identified the most suitable function (logistic function) to construct a two-level mixed effects (NLME) CW model with the forest block and sample plot-level effects included as random effects in the model. Four methods for selecting sample bamboos per sample plot (largest bamboo, medium-sized bamboo, smallest bamboo, and randomly selected bamboos) and eight sample sizes (1-8 selected bamboos per sample plot) were evaluated to calibrate our NLME CW model. Using diameter at breast height (DBH), height to crown base (HCB), arithmetic mean diameter at breast height (MDBH), and height (H) as predictor variables, the model produced the best fit statistics (Max R2, min RMSE, and TRE). This model was further improved by introducing random effects at two levels. The results showed a positive correlation of CW with HCB and DBH and a negative correlation with H. The smallest two bamboo poles per sample plot used to estimate the random effects of the NLME model provided a satisfactory compromise regarding measurement cost, model efficiency, and prediction accuracy. The presented NLME CW model may guide effective management and carbon estimation of bamboo forests.

19.
Saudi J Biol Sci ; 30(2): 103549, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36619679

RESUMEN

Cinnamomum is the largest genus of Lauraceae family and has been used as spices, food, and food additives by the people. Total 15 Cinnamomum species are distributed in different parts of Indian sub-continent. Different parts (leaves, stem bark, stem wood, roots, flowers, and fruits) of these species were shade-dried and used for the determination of essential oils. A total of 19 essential oils were identified and quantified from the different parts of (leaf, stem bark, stem wood, root, flower, and fruit) of 15 Cinnamomum species. The stem bark of C. altissimum was rich in the presence of essential oils (52.2 %) whereas minimum levels of essential oils were recorded in roots (17.9 %). The γ-terpinene (11.1 %) was reported as the major component essential oil in C. subavenium flowers. Methanol extract of C. camphora stem wood showed stronger lowest minimum inhibitory concentration against S. aureus (25 ± 0.01 µg/ml), H. pylori (29 ± 0.05 µg/ml), B. subtilis (31 ± 0.03 µg/ml), E. faecalis (33 ± 0.01 µg/ml), C. albicans (38 ± 0.03 µg/ml) when compared to amoxycillin (S. aureus 56 ± 0.05 µg/ml; B. subtilis 27 ± 0.04 µg/ml, E. faecalis 22 ± 0.01 µg/ml), streptomycin (H. pylori 38 ± 0.02 µg/ml) and fluconazole (C. albicans 56 ± 0.01 µg/ml). Methanolic extract of C. camphora stem wood demonstrated maximum antimicrobial activity against S. aureus, H. pylori, B. subtilis, E. faecalis and C. albicans. The essential oil of C. altissimum stem bark displayed significant lowest MIC against S. aureus (21 ± 0.03 µg/ml), E. coli (22 ± 0.03 µg/ml), E. cloacae (37 ± 0.06 µg/ml), L. monocytogenes (47 ± 0.08 µg/ml), and P. chrysogenum (101 ± 0.07 µg/ml) when compared to amoxycillin (E. coli 18 ± 0.01 µg/ml, E. cloacae 21 ± 0.05 µg/ml, L. monocytogenes 31 ± 0.03 µg/ml), and fluconazole (P. chrysogenum 101 ± 0.07 µg/ml). The essential oil of C. altissimum stem bark displayed maximum antimicrobial activity against S. aureus, E. coli, E. cloacae, L. monocytogenes, and P. chrysogenum. Cinnamomum essential oils may be used as an alternative source of antibacterial and antifungal compounds in the treatment of various types of infections.

20.
ACS Appl Mater Interfaces ; 15(4): 5086-5098, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36669233

RESUMEN

High-performance energy storage devices (HPEDs) play a critical role in the realization of clean energy and thus enable the overarching pursuit of nonpolluting, green technologies. Supercapacitors are one class of such lucrative HPEDs; however, a serious limiting factor of supercapacitor technology is its sub-par energy density. This report presents hitherto unchartered pathway of physical deformation, chemical dealloying, and microstructure engineering to produce ultrahigh-capacitance, energy-dense NiMn alloy electrodes. The activated electrode delivered an ultrahigh specific-capacitance of 2700 F/cm3 at 0.5 A/cm3. The symmetric device showcased an excellent energy density of 96.94 Wh/L and a remarkable cycle life of 95% retention after 10,000 cycles. Transmission electron microscopy and atom probe tomography studies revealed the evolution of a unique hierarchical microstructure comprising fine Ni/NiMnO3 nanoligaments within MnO2-rich nanoflakes. Theoretical analysis using density functional theory showed semimetallic nature of the nanoscaled oxygen-vacancy-rich NiMnO3 structure, highlighting enhanced carrier concentration and electronic conductivity of the active region. Furthermore, the geometrical model of NiMnO3 crystals revealed relatively large voids, likely providing channels for the ion intercalation/de-intercalation. The current processing approach is highly adaptable and can be applied to a wide range of material systems for designing highly efficient electrodes for energy-storage devices.

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