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1.
Nanotechnology ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710165

RESUMO

For deep ultraviolet (UV-C) photodetectors, Gallium oxide (Ga2O3) is a suitable candidate owing to its intrinsic ultra-wide band gap and high stability. However, its detection is limited within the UV-C region, which restricts it to cover a broad range, especially in visible and near-infrared (NIR) region. Therefore, constructing a heterostructure of Ga2O3 with an appropriate material having a narrow band gap is a worthwhile approach to compensate for it. In this category, PtS2 group-10 transitional metal dichalcogenide (TMDC) stands at the top owing to its narrow band gap (0.25-1.65 eV), high mobility, and stability for heterostructure synthesis. Moreover, heterostructure with Ga2O3 sensing in UV and PtS2 broad response in visible and IR range can broaden the spectrum from UV to NIR and to build broadband photodetector. In this work, we fabricated a 2D-3D PtS2-x/Ga2O3 heterostructure based broadband photodetector with detection from UV-C to NIR region. In addition, the PtS2-x/Ga2O3 device shows a high responsivity of 38.7 AW 1 and detectivity of 4.8×1013 Jones under 1100 nm light illumination at 5V bias. A fast response of 90 ms /86 ms illustrates the device's fast speed. An interface study between the PtS2-x and Ga2O3 was conducted using X-ray photoelectron spectroscopy and Ultraviolet photoelectron spectroscopy (UPS) which confirmed type-I band alignment. Finally, based on their band alignment study, a carrier transport mechanism was proposed at the interface. This work offers a new opportunity to fabricate large-area high-performance 2D-3D heterostructures based photodetectors for future optoelectronics devices.

2.
New Phytol ; 242(5): 2059-2076, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38650352

RESUMO

Wide variation in amenability to transformation and regeneration (TR) among many plant species and genotypes presents a challenge to the use of genetic engineering in research and breeding. To help understand the causes of this variation, we performed association mapping and network analysis using a population of 1204 wild trees of Populus trichocarpa (black cottonwood). To enable precise and high-throughput phenotyping of callus and shoot TR, we developed a computer vision system that cross-referenced complementary red, green, and blue (RGB) and fluorescent-hyperspectral images. We performed association mapping using single-marker and combined variant methods, followed by statistical tests for epistasis and integration of published multi-omic datasets to identify likely regulatory hubs. We report 409 candidate genes implicated by associations within 5 kb of coding sequences, and epistasis tests implicated 81 of these candidate genes as regulators of one another. Gene ontology terms related to protein-protein interactions and transcriptional regulation are overrepresented, among others. In addition to auxin and cytokinin pathways long established as critical to TR, our results highlight the importance of stress and wounding pathways. Potential regulatory hubs of signaling within and across these pathways include GROWTH REGULATORY FACTOR 1 (GRF1), PHOSPHATIDYLINOSITOL 4-KINASE ß1 (PI-4Kß1), and OBF-BINDING PROTEIN 1 (OBP1).


Assuntos
Estudo de Associação Genômica Ampla , Reguladores de Crescimento de Plantas , Populus , Populus/genética , Reguladores de Crescimento de Plantas/metabolismo , Redes Reguladoras de Genes , Epistasia Genética , Genes de Plantas , Regulação da Expressão Gênica de Plantas , Fenótipo , Transdução de Sinais/genética
3.
Small ; : e2309277, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618656

RESUMO

Ga2O3 has emerged as a promising material for the wide-bandgap industry aiming at devices beyond the limits of conventional silicon. Amorphous Ga2O3 is widely being used for flexible electronics, but suffers from very high resistivity. Conventional methods of doping like ion implantation require high temperatures post-processing, thereby limiting their use. Herein, an unconventional method of doping Ga2O3 films with Si, thereby enhancing its electrical properties, is reported. Ion-beam sputtering (500 eV Ar+) is utilized to nanopattern SiO2-coated Si substrate leaving the topmost part rich in elemental Si. This helps in enhancing the carrier conduction by increasing n-type doping of the subsequently coated 5 nm amorphous Ga2O3 films, corroborated by room-temperature resistivity measurement and valence band spectra, respectively, while the nanopatterns formed help in better light management. Finally, as proof of concept, metal-semiconductor-metal (MSM) photoconductor devices fabricated on doped, rippled films show superior properties with responsivity increasing from 6 to 433 mA W-1 while having fast detection speeds of 861 µs/710 µs (rise/fall time) as opposed to non-rippled devices (377 ms/392 ms). The results demonstrate a facile, cost-effective, and large-area method to dope amorphous Ga2O3 films in a bottom-up approach which may be employed for increasing the electrical conductivity of other amorphous oxide semiconductors as well.

4.
Int J Biol Macromol ; 268(Pt 2): 131847, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38677678

RESUMO

Combining the versatility of electrospinning with the biocompatibility of Polycaprolactone and Collagen, this study aims to create advanced 3D nano scaffolds for effective drug delivery. Ceramic materials like hydroxyapatite (nHAp) are incorporated as bioactive agents in the fibers. Electrospun PCL (Polycaprolactone)/collagen nanofibers and PVA (Poly-vinyl alcohol)/collagen are promising tissue-engineering substitutes with high biocompatibility, low cytotoxicity, and great tensile strength. Small pores in these nanofibers play a major role in drug delivery system. Owing to its short half-life, limited solubility, restricted bioavailability as well as re-crystallization concerns, the application of Cetirizine (CIT) has found little relevance. Electrospun nanofibers impregnated with CIT provide an excellent solution to combat these limitations, yield sustained drug release along with hampering drug re-crystallization. CIT-loaded polyvinyl alcohol (PVA)/collagen (Col) and CIT-loaded PVA/Col/nHAp nanofibers were characterized and further CIT anti-crystallization as well as release behaviors were investigated. FESEM and HRTEM were used to observe the morphology of the as-synthesized nanofibers. FTIR spectroscopy, water contact angle measurement and drug release studies verified the differences in performance of CIT-loaded PVA/Col and PVA/Col/nHAp nanofibers. The release trend of CIT through these as-synthesized nanoscaffolds was analyzed by various kinetic models and exhibited sustained release of CIT for up to 96 h.

5.
G3 (Bethesda) ; 14(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38325329

RESUMO

Plant regeneration is an important dimension of plant propagation and a key step in the production of transgenic plants. However, regeneration capacity varies widely among genotypes and species, the molecular basis of which is largely unknown. Association mapping methods such as genome-wide association studies (GWAS) have long demonstrated abilities to help uncover the genetic basis of trait variation in plants; however, the performance of these methods depends on the accuracy and scale of phenotyping. To enable a large-scale GWAS of in planta callus and shoot regeneration in the model tree Populus, we developed a phenomics workflow involving semantic segmentation to quantify regenerating plant tissues over time. We found that the resulting statistics were of highly non-normal distributions, and thus employed transformations or permutations to avoid violating assumptions of linear models used in GWAS. We report over 200 statistically supported quantitative trait loci (QTLs), with genes encompassing or near to top QTLs including regulators of cell adhesion, stress signaling, and hormone signaling pathways, as well as other diverse functions. Our results encourage models of hormonal signaling during plant regeneration to consider keystone roles of stress-related signaling (e.g. involving jasmonates and salicylic acid), in addition to the auxin and cytokinin pathways commonly considered. The putative regulatory genes and biological processes we identified provide new insights into the biological complexity of plant regeneration, and may serve as new reagents for improving regeneration and transformation of recalcitrant genotypes and species.


Assuntos
Estudo de Associação Genômica Ampla , Populus , Populus/genética , Genes de Plantas , Locos de Características Quantitativas , Ácidos Indolacéticos
6.
Hortic Res ; 10(8): uhad125, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560019

RESUMO

Adventitious rooting (AR) is critical to the propagation, breeding, and genetic engineering of trees. The capacity for plants to undergo this process is highly heritable and of a polygenic nature; however, the basis of its genetic variation is largely uncharacterized. To identify genetic regulators of AR, we performed a genome-wide association study (GWAS) using 1148 genotypes of Populus trichocarpa. GWASs are often limited by the abilities of researchers to collect precise phenotype data on a high-throughput scale; to help overcome this limitation, we developed a computer vision system to measure an array of traits related to adventitious root development in poplar, including temporal measures of lateral and basal root length and area. GWAS was performed using multiple methods and significance thresholds to handle non-normal phenotype statistics and to gain statistical power. These analyses yielded a total of 277 unique associations, suggesting that genes that control rooting include regulators of hormone signaling, cell division and structure, reactive oxygen species signaling, and other processes with known roles in root development. Numerous genes with uncharacterized functions and/or cryptic roles were also identified. These candidates provide targets for functional analysis, including physiological and epistatic analyses, to better characterize the complex polygenic regulation of AR.

7.
ACS Omega ; 8(32): 29247-29252, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37599978

RESUMO

The present study was carried out to formulate and determine the sensory, proximate, phytochemical, and antioxidant properties of matcha hard candies incorporated with spices such as ginger (Zingiber officinale Rosc.), cinnamon (Cinnamomum zeylanicum and Cinnamon cassia), and holy basil (tulsi) (Ocimum sanctum L.). Standardized matcha (Camellia sinensis) hard candy was taken as a control, and spices/herbs were incorporated in different concentrations. The best formulation was GC5 (2% ginger powder) for matcha ginger hard candy, CZ10 (0.9% cinnamon powder) for matcha cinnamon hard candy, and TC7 (3% tulsi powder) for matcha tulsi hard candy. These formulations were selected based on the organoleptic evaluation. Furthermore, these selected hard candies were evaluated for the determination of proximate, phytochemical, and antioxidant profiles which exhibited significant results. This study demonstrates the excellent nutritional and phytochemical potential that spiced matcha hard candy has for use as a nutraceutical food product.

9.
Nucl Med Commun ; 44(6): 463-470, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36897059

RESUMO

OBJECTIVE: Bone is considered as the third most common site of metastases, besides lung and liver. Early detection of skeletal metastases aids in better management of skeletal-related events. In the present study cold kit-based 2,2 ' ,2 '' -(10-(2-((diphosphonomethyl)amino)-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl) triacetic acid (BPAMD) was labeled with 68 Ga. The radiolabeling parameters and clinical evaluation in patients with suspected bone metastases were compared with routinely used 99m Tc-methylenediphosphonate ( 99m Tc-MDP). METHODOLOGY: The kit components of MDP were incubated with at room temperature for 10 min, followed by radiochemical purity testing using thin-layer chromatography. For radiolabeling of BPAMD, the cold kit components reconstituted in 400 µL of HPLC grade water were transferred and incubated with 68 GaCl 3 in the reactor vessel of the fluidic module at 95°C for 20 min. Radiochemical yield and purity were determined with instant thin-layer chromatography using 0.5 M sodium citrate as mobile phase. For clinical evaluation, patients ( n = 10) with suspected bone metastases were enrolled. 99m Tc-MDP and 68 Ga-BPAMD scans were performed on two different days in random order. Imaging outcomes were noted and compared. RESULTS: Radiolabeling of both tracers is facile using cold kit, although BPAMD requires heating. The radiochemical purity was observed to be greater than 99% for all preparations. Both MDP and BPAMD detected skeletal lesions; however, additional lesions were detected in total of seven patients which were not visualized clearly on 99m Tc-MDP scan. CONCLUSION: BPAMD can be easily tagged with 68 Ga using cold kits. The radiotracer is suitable and efficient for detection of bone metastases using PET/computed tomography.


Assuntos
Neoplasias Ósseas , Tomografia por Emissão de Pósitrons , Humanos , Tomografia por Emissão de Pósitrons/métodos , Difosfonatos , Compostos Radiofarmacêuticos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Medronato de Tecnécio Tc 99m
10.
Plant Phenomics ; 2022: 9893639, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059601

RESUMO

The abilities of plant biologists and breeders to characterize the genetic basis of physiological traits are limited by their abilities to obtain quantitative data representing precise details of trait variation, and particularly to collect this data at a high-throughput scale with low cost. Although deep learning methods have demonstrated unprecedented potential to automate plant phenotyping, these methods commonly rely on large training sets that can be time-consuming to generate. Intelligent algorithms have therefore been proposed to enhance the productivity of these annotations and reduce human efforts. We propose a high-throughput phenotyping system which features a Graphical User Interface (GUI) and a novel interactive segmentation algorithm: Semantic-Guided Interactive Object Segmentation (SGIOS). By providing a user-friendly interface and intelligent assistance with annotation, this system offers potential to streamline and accelerate the generation of training sets, reducing the effort required by the user. Our evaluation shows that our proposed SGIOS model requires fewer user inputs compared to the state-of-art models for interactive segmentation. As a case study of the use of the GUI applied for genetic discovery in plants, we present an example of results from a preliminary genome-wide association study (GWAS) of in planta regeneration in Populus trichocarpa (poplar). We further demonstrate that the inclusion of a semantic prior map with SGIOS can accelerate the training process for future GWAS, using a sample of a dataset extracted from a poplar GWAS of in vitro regeneration. The capabilities of our phenotyping system surpass those of unassisted humans to rapidly and precisely phenotype our traits of interest. The scalability of this system enables large-scale phenomic screens that would otherwise be time-prohibitive, thereby providing increased power for GWAS, mutant screens, and other studies relying on large sample sizes to characterize the genetic basis of trait variation. Our user-friendly system can be used by researchers lacking a computational background, thus helping to democratize the use of deep segmentation as a tool for plant phenotyping.

11.
BMC Public Health ; 22(1): 1199, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705940

RESUMO

BACKGROUND: Tobacco consumption remains a public health issue and is one of the major causes of death in India. This study presents a validated conceptual model to assess the interaction between education, perceived application of tobacco control measures, type of tobacco and their effects on the intention to quit tobacco. Additionally, the direct and mediating roles of tobacco use -frequency, -duration, and -dependency on the intention to quit is also investigated. METHODS: An analytical cross-sectional study was carried out, and data from tobacco users of six randomly selected states in India was collected via face-to-face interviews. Structural equation modeling (SEM) was performed using R v 3.6.3 to test the model fit and to explore the association between tobacco control measures and the intention to quit tobacco. RESULTS: From 1962 tobacco users, 43.7% wanted to quit tobacco immediately. Tambakoo (57.7%) was the most common type of tobacco used and 68.9% said that minors could buy tobacco. Findings from SEM showed that that one standard deviation (SD) increase in the perceived application of tobacco control measures is directly associated with a 0.181 SD increase in the intention to quit tobacco (B = 0.181, P < 0.001), and this effect was partially mediated by frequency of tobacco consumption (B = 0.06, P < 0.05). Also, a better education level was associated with a higher intention to quit tobacco (B = 0.14, P < 0.001). CONCLUSIONS: To conclude, the application of tobacco control measures and a better education level may positively affect the intention to quit tobacco. The frequency of tobacco use and the number of influencers play an essential role in deciding to quit. In future, longitudinal studies are recommended to further substantiate the evidence.


Assuntos
Intenção , Abandono do Hábito de Fumar , Estudos Transversais , Humanos , Análise de Classes Latentes , Nicotiana , Uso de Tabaco/prevenção & controle
12.
Nanotechnology ; 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35675743

RESUMO

Gallium oxide is an ultra-wide band gap semiconductor (Eg > 4.4 eV), best suited intrinsically for the fabrication of solar-blind photodetectors. Apart from its crystalline phases, amorphous Ga2O3 based solar-blind photodetector offer simple and facile growth without the hassle of lattice matching and high temperatures for growth and annealing. However, they often suffer from long response times which hinders any practical use. Herein, we report a simple and cost-effective method to enhance the device performance of amorphous gallium oxide thin film photodetector by nanopatterning the surface using a broad and low energy Ar+ ion beam. The ripples formed on the surface of gallium oxide thin film lead to the formation of anisotropic conduction channels along with an increase in the surface defects. The defects introduced in the system act as recombination centers for the charge carriers bringing about a reduction in the decay time of the devices, even at zero-bias. The fall time of the rippled devices, therefore, reduces, making the devices faster by more than 15 times. This approach of surface modification of gallium oxide provides a one-step, low cost method to enhance the device performance of amorphous thin films which can help in the realization of next-generation optoelectronics.

13.
An Acad Bras Cienc ; 92(3): e20190596, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111819

RESUMO

Microgreen based functional juice blends containing fenugreek (Trigonella foenum-graecum), kinnow mandarin (Citrus reticulate) and aloe vera (Aloe brobadensis) in different ratios were blended with sorbitol and stevia. The different ratios of juice blends were analyzed for total soluble solids, sedimentation, viscosity and titrable acidity. They were also screened for total phenolic content, total carotenoid content and antioxidant properties such as DPPH, reducing power and metal chelating activity. The formulation with highest TPC, TCC and antioxidant property was selected to optimize a microgreen based functional juice. The optimized microgreen blend formulation had 20 ml 100-1 ml microgreen juice, 40 ml 100-1 ml kinnow juice, 8.5 ml 100-1 ml sorbitol, 1.78 g 100-1 ml stevia and 29.72 ml 100-1 ml aloe vera juice. It had high protein, minerals (sodium and potassium) and vitamin (vitamin C) content as well as good source beta-carotene, phenols and antioxidants. Antioxidant helps in reducing diabetic complications by reducing the oxidative stress and because of their protective action against reactive oxygen species.


Assuntos
Antioxidantes , Frutas , Alimento Funcional , Antioxidantes/análise , Antioxidantes/farmacologia , Ácido Ascórbico/análise , Bebidas/análise , Frutas/química , Fenóis/análise
14.
Curr Diabetes Rev ; 16(4): 301-312, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31389314

RESUMO

Diabetes is a globally prevalent chronic metabolic disease characterized by blood glucose levels higher than the normal levels. Sugar, a common constituent of diet, is also a major factor often responsible for elevating the glucose level in diabetic patients. However, diabetic patients are more prone to eat sweets amongst the human population. Therefore, we find a popular consumption of zero or low-calorie sweeteners, both natural and artificial. But, the uses of these sweeteners have proved to be controversial. Thus, the purpose of this review was to critically analyze and highlight the considerations needed for the development of sugar-free or low-calorie products for diabetic patients. For this purpose, various measures are taken such as avoiding sugary foods, using natural nectar, artificial sweeteners, etc. It cannot be ignored that many health hazards are associated with the overconsumption of artificial sweeteners only. These sweeteners are high-risk compounds and a properly balanced consideration needs to be given while making a diet plan for diabetic patients.


Assuntos
Diabetes Mellitus/dietoterapia , Edulcorantes/administração & dosagem , Diabetes Mellitus/metabolismo , Ingestão de Energia , Tecnologia de Alimentos , Humanos , Ciências da Nutrição , Edulcorantes/efeitos adversos
15.
Curr Aging Sci ; 12(1): 15-27, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31109282

RESUMO

The process of aging is characterized by numerous changes in the body which has an overall negative effect on the health and lifestyle of elderly. Nutrition deserves special attention as an individual reaches old age. It plays a vital role in affecting the quality of life, including physical, mental and social health. The physiological decline in food intake is very common among older age and this result in nutritional deficiencies. These increased nutritional deficiencies are the major risk factors for certain chronic diseases and deteriorated age related health. Thus, the adoption of nutritional intervention can be a measure to tackle the current situation of nutritional deficiencies and promote a healthy lifestyle.


Assuntos
Envelhecimento/metabolismo , Suplementos Nutricionais , Alimentos Fortificados , Desnutrição/dietoterapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Avaliação Geriátrica/métodos , Humanos , Masculino , Desnutrição/prevenção & controle , Necessidades Nutricionais/fisiologia , Estado Nutricional , Prognóstico , Qualidade de Vida , Medição de Risco , Resultado do Tratamento
16.
An Acad Bras Cienc ; 90(4): 3871-3878, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30365720

RESUMO

Piper betle L., is an evergreen perennial creeper belonging to family Piperaceae and is known to possess numerous medicinal properties. Current study focuses on evaluating antioxidant and antimicrobial potential of betel leaf. For the present study, distilled water, hexane, acetone and ethanolic extracts of two varieties of betel leaves: Meetha paan and Banarasi paan were used. Biochemical tests such as proximate analysis (moisture, ash, protein, lipids, minerals viz., sodium and potassium), antioxidant activity tests (DPPH radical scavenging activity, total phenolics, ascorbic acid, reducing power) and antimicrobial test (antibacterial and antifungal susceptibility test) against four pathogens viz., B. subtilis, E. coli, A. niger and S. cerevisiae were determined. Ethanolic extract had the highest antioxidant activity (89.46% inhibition), while the aqueous extract exhibited lowest antioxidant activity (62.03% inhibition). With increasing concentration (5, 10, 25 and 50 µg/mL), the reducing power of leaf extracts also increased. The ascorbic acid was not significant in Banarasi paan (5.21mg/100 g) and Meetha paan (5.20mg/100 g). The highest antibacterial activity of ethanolic extract (Banarasi paan) may be attributed to the presence of phytosterols in the leaf varieties. Antioxidant and antimicrobial potential study will help to build a database and promote the utilization of betel leaf as a medicinal herb.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Piper betle/química , Extratos Vegetais/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Testes de Sensibilidade Microbiana , Folhas de Planta/química
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