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1.
Mol Biol Rep ; 49(1): 351-361, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34724129

RESUMO

BACKGROUND: The taxonomic status and geographical distribution of M. tengara are vague. No genetic diversity and phylogenetic study have been done till now to resolve its identity and distribution. In the present study, an integrated taxonomic approach has been applied to clarify the taxonomic status, identity, and distribution of bagrid catfish, Mystus tengara. METHODS AND RESULTS: Comparative morphometric evaluation of M. tengara identified in the present study from distant geographical locations revealed variations of the traits in response to body length and environment, without significant genetic distance. The observed morphometric traits of M. tengara were found to be overlapping with available morphometric traits of M. tengara, M. carcio and M. vittatus. Maximum likelihood and Bayesian phylogenetic analysis based on mitochondrial cytochrome c oxidase (COI) gene also could not resolve their identity, and five paraphyletic clades comprising of M. tengara, M. vittatus, and M. carcio from India, Nepal, and Bangladesh were observed. Morphological and genetic evidence along with comparative evaluation of M. tengara, from its type locality, we consider M. tengara identified in the present study to be true, with its distribution extending from North East India to West Bengal, North India, Central India, Northern peninsular India, and Bangladesh. CONCLUSION: The observation of paraphyletic subclades and evaluation of genetic distance between subclades reveals the presence of four cryptic species. Further confirmation on the identity of M. vittatus and M. carcio, by an integrated taxonomic approach based on fresh specimens collected from the type locality, is required.


Assuntos
Peixes-Gato/anatomia & histologia , Peixes-Gato/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Animais , Bangladesh , Teorema de Bayes , Peixes-Gato/genética , Proteínas de Peixes/genética , Índia , Funções Verossimilhança , Proteínas Mitocondriais/genética , Nepal , Filogenia , Filogeografia
2.
Arch Environ Contam Toxicol ; 79(4): 488-499, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33215293

RESUMO

Personal care product (PCP) chemicals have a greater chance of accumulation in the aquatic environments because of their volume of use. PCPs are biologically active substances that can exert an adverse effect on the ecology and food safety. Information on the status of these substances in Indian open water ecosystems is scarce. In this paper, we report the incidence of two synthetic antimicrobials, triclosan (TCS), including its metabolite methyl-triclosan (Me-TCS) and triclocarban (TCC) in Torsa, a transboundary river flowing through India. In water TCS and TCC were detected at levels exceeding their respective PNEC (Predictive No Effect Concentration). Both the compounds were found to be bioaccumulative in fish. TCS concentration (91.1-589 µg/kg) in fish was higher than that of TCC (29.1-285.5 µg/kg). The accumulation of residues of the biocides varied widely among fishes of different species, ecological niche, and feeding habits. Me-TCS could be detected in fishes and not in water. The environmental hazard quotient of both TCS and TCC in water indicated a moderate risk. However, the health risk analysis revealed that fishes of the river would not pose any direct hazard to human when consumed. This is the first report of the occurrence of these PCP chemicals in a torrential river system of the eastern Himalayan region.


Assuntos
Anti-Infecciosos/análise , Carbanilidas/análise , Monitoramento Ambiental , Triclosan/análogos & derivados , Poluentes Químicos da Água/análise , Animais , Desinfetantes , Ecossistema , Peixes , Humanos , Índia , Rios/química , Segurança , Triclosan/análise , Água/análise
3.
Fish Physiol Biochem ; 44(1): 95-108, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28822029

RESUMO

In the present study, full-length CYP1A cDNA from Catla catla (Catla) has been identified, and its real-time quantitative reverse transcription PCR (qRT-PCR) expression has been evaluated in different tissues, developmental stages (0, 3, 6, 12 and 24 h and 5, 7 and 9 days post-fertilization) and copper sulphate and benzo(a)pyrene (BaP)-treated 5-day post-fertilization (dpf) larvae (6 to 6.5 mm). Various structural, comparative and phylogenetic analyses of the deduced amino acid sequence revealed that the identified gene of Catla belongs to the CYP1A1 subfamily. Among different tissues of Catla, the highest CYP1A expression was observed in the kidney followed by the liver, muscle, gill, intestine and brain. CYP1A mRNA expression was detected during all the larval developmental stages, including the unfertilized egg with the highest expression on 9 dpf. BaP (3.5 ppb) and copper sulphate (sublethal dose 0.516 ppm) challenge test for 96 h to Catla larvae revealed the highest CYP1A1 expression at 48 h post-challenge. CYP1A1 transcript also showed a concentration-dependent increase in expression following exposure at 1.75 and 3.5 ppb of BaP for 48 h. Its expression profiling indicates that it is functional at early developmental stages. It can also be used to develop a specific biomarker tool for monitoring environmental pollution.


Assuntos
Benzo(a)pireno/farmacologia , Sulfato de Cobre/farmacologia , Cipriniformes/genética , Citocromo P-450 CYP1A1/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Cipriniformes/crescimento & desenvolvimento , Citocromo P-450 CYP1A1/metabolismo , DNA Complementar/genética , DNA Complementar/metabolismo , Larva/genética , Larva/metabolismo , Modelos Moleculares , Filogenia , Conformação Proteica
4.
Indian J Exp Biol ; 53(5): 273-80, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26040024

RESUMO

The decapod crustacean Penaeus monodon survives large fluctuations in salinity through osmoregulation in which Na+/K(+)-ATPase (NKA) activity in the gills plays a central role. Adult P. monodon specimens were gradually acclimatized to 5, 25 and 35 per thousand salinities and maintained for 20 days to observe long-term alterations in NKA expression. Specific NKA activity assayed in gill tissues was found to be 3 folds higher at 5 per thousand compared to 25 per thousand (isosmotic salinity) and 0.48 folds lower at 35 per thousand. The enzyme was immunolocalized in gills using mouse α-5 monoclonal antibody that cross reacts with P. monodon NKA α-subunit. At 5 per thousand the immunopositive cells were distributed on lamellar tips and basal lamellar epithelium of the secondary gill filaments and their number was visibly higher. At both 25 per thousand and 35 per thousand NKA positive cells were observed in the inter-lamellar region but the expression was more pronounced at 25 per thousand. Gill architecture was normal at all salinities. However, the 1.5 fold increase in NKA α-subunit mRNA at 5 per thousand measured by quantitative RT-PCR (qRT-PCR) using EF1α as reference gene was not statistically significant. The study confirms the osmoregulating ability of P. monodon like other crustaceans at lower salinities. It is likely that significant increase in NKA transcript level happens at an earlier time point. At higher salinities all three methods record only marginal or no change from isosmotic controls confirming the hypothesis that the animal largely osmoconforms in hyperosmotic environment.


Assuntos
Concentração Osmolar , Salinidade , Cloreto de Sódio/farmacologia , ATPase Trocadora de Sódio-Potássio/biossíntese , Aclimatação/fisiologia , Animais , Água Doce , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Brânquias/enzimologia , Camundongos , Penaeidae/enzimologia , RNA Mensageiro/biossíntese
5.
Artigo em Inglês | MEDLINE | ID: mdl-38305794

RESUMO

Opsarius siangi sp. nov., a previously undocumented species, has been identified from Siang River, Pasighat, Arunachal Pradesh, India. This newly described species is distinguished by a suite of unique morphological characteristics, notably including a complete lateral line, consisting of 65-77 scales, 32-39 pre-dorsal scales, 12-15 scales positioned between dorsal fin origin and lateral line, presence of two pairs of barbels, body depth ranging from 18.80% to 27.42% of standard length and a distinct pattern of 8-15 vertical bars adorning the body. A comprehensive genetic analysis was conducted by scrutinizing 78 Cytochrome oxidase I (COI) sequences extracted from Chedrinae fishes, with particular focus on Opsarius and Barilius genera. Phylogenetic analysis revealed that O. siangi sp. nov. occupies a distinctive clade, displaying close affinity with O. shacra. Intraspecific K2P genetic divergence, assessed at 0.02, falls well within established species delineation thresholds, while interspecific divergence in comparison to O. shacra was recorded at 0.112. Complementary species delimitation methodologies, including BIN and bPTP, further underscore taxonomic uniqueness of O. siangi sp. nov., within Chedrinae family. This description enriches our understanding of biodiversity within Siang River ecosystem and underscores the merit of employing multi-pronged approaches in taxonomic investigations.

6.
Biomedicines ; 12(7)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39062100

RESUMO

The tumor microenvironment (TME) is composed of various cellular components such as tumor cells, stromal cells including fibroblasts, adipocytes, mast cells, lymphatic vascular cells and infiltrating immune cells, macrophages, dendritic cells and lymphocytes. The intricate interplay between these cells influences tumor growth, metastasis and therapy failure. Significant advancements in breast cancer therapy have resulted in a substantial decrease in mortality. However, existing cancer treatments frequently result in toxicity and nonspecific side effects. Therefore, improving targeted drug delivery and increasing the efficacy of drugs is crucial for enhancing treatment outcome and reducing the burden of toxicity. In this review, we have provided an overview of how tumor and stroma-derived osteopontin (OPN) plays a key role in regulating the oncogenic potential of various cancers including breast. Next, we dissected the signaling network by which OPN regulates tumor progression through interaction with selective integrins and CD44 receptors. This review addresses the latest advancements in the roles of splice variants of OPN in cancer progression and OPN-mediated tumor-stromal interaction, EMT, CSC enhancement, immunomodulation, metastasis, chemoresistance and metabolic reprogramming, and further suggests that OPN might be a potential therapeutic target and prognostic biomarker for the evolving landscape of cancer management.

8.
J Cancer Res Ther ; 19(5): 1462-1464, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37787331

RESUMO

Lactating adenomas, though considered being benign, sometimes turn out to be malignant. We are hereby presenting two cases of lactating adenomas which turned out to be harboring infiltrating duct cell carcinoma (DCC). Two lactating women with mass in the breast were referred from surgery for fine-needle aspiration cytology and biopsy. On histopathology, it was found that both had infiltrating DCC (either as collision tumor or as a malignant transformation of lactating adenoma). These cases point toward some association between lactating adenoma and DCC, however, small it may be. Therefore, any mass lesion in the breast should be followed up under strict vigilance for an early diagnosis and management of this deadly disease. A large sample size and elaborate study are required to frame its prognostic relevance. Like estrogen receptor and progesterone receptor, prolactin and prolactin receptor expression can be exploited for developing newer receptor-targeted therapy.


Assuntos
Adenoma , Neoplasias da Mama , Carcinoma , Neoplasias Gastrointestinais , Feminino , Humanos , Lactação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Adenoma/patologia , Biópsia por Agulha Fina
9.
Artif Cells Nanomed Biotechnol ; 51(1): 74-82, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36762883

RESUMO

Recent years have seen the development of a variety of mammalian library approaches for display and secretion mode. Advantages include library approaches for engineering, preservation of precious immune repertoires and their repeated interrogation, as well as screening in final therapeutic format and host. Mammalian display approaches for antibody optimization exploit these advantages, necessitating the generation of large libraries but in turn enabling early screening for both manufacturability and target specificity. For suitable libraries, high antibody integration rates and resulting monoclonality need to be balanced - we present a solution for sufficient transmutability and acceptable monoclonality by applying an optimized ratio of coding to non-coding lentivirus. The recent advent of microfluidic-assisted hit discovery represents a perfect match to mammalian libraries in secretion mode, as the lower throughput fits well with the facile generation of libraries comprising a few million functional clones. In the presented work, Chinese Hamster Ovary cells were engineered to both express the target of interest and secrete antibodies in relevant formats, and specific clones were strongly enriched by high throughput screening for autocrine cellular binding. The powerful combination of mammalian secretion libraries and microfluidics-assisted hit discovery could reduce attrition rates and increase the probability to identify the best possible therapeutic antibody hits faster.


Assuntos
Anticorpos , Microfluídica , Cricetinae , Animais , Células CHO , Cricetulus
10.
MAbs ; 15(1): 2251190, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37646089

RESUMO

Recently, there has been a co-evolution of mammalian libraries and diverse microfluidic approaches for therapeutic antibody hit discovery. Mammalian libraries enable the preservation of full immune repertoires, produce hit candidates in final format and facilitate broad combinatorial bispecific antibody screening, while several available microfluidic methodologies offer opportunities for rapid high-content screens. Here, we report proof-of-concept studies exploring the potential of combining microfluidic technologies with mammalian libraries for antibody discovery. First, antibody secretion, target co-expression and integration of appropriate reporter cell lines enabled the selection of in-trans acting agonistic bispecific antibodies. Second, a functional screen for internalization was established and comparison of autocrine versus co-encapsulation setups highlighted the advantages of an autocrine one cell approach. Third, synchronization of antibody-secreting cells prior to microfluidic screens reduced assay variability. Furthermore, a display to secretion switchable system was developed and applied for pre-enrichment of antibody clones with high manufacturability in conjunction with subsequent screening for functional properties. These case studies demonstrate the system's feasibility and may serve as basis for further development of integrated workflows combining manufacturability sorting and functional screens for the identification of optimal therapeutic antibody candidates.


Assuntos
Anticorpos Biespecíficos , Animais , Linhagem Celular , Mamíferos
11.
Front Plant Sci ; 14: 1282217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192691

RESUMO

Sensor-based decision tools provide a quick assessment of nutritional and physiological health status of crop, thereby enhancing the crop productivity. Therefore, a 2-year field study was undertaken with precision nutrient and irrigation management under system of crop intensification (SCI) to understand the applicability of sensor-based decision tools in improving the physiological performance, water productivity, and seed yield of soybean crop. The experiment consisted of three irrigation regimes [I1: standard flood irrigation at 50% depletion of available soil moisture (DASM) (FI), I2: sprinkler irrigation at 80% ETC (crop evapo-transpiration) (Spr 80% ETC), and I3: sprinkler irrigation at 60% ETC (Spr 60% ETC)] assigned in main plots, with five precision nutrient management (PNM) practices{PNM1-[SCI protocol], PNM2-[RDF, recommended dose of fertilizer: basal dose incorporated (50% N, full dose of P and K)], PNM3-[RDF: basal dose point placement (BDP) (50% N, full dose of P and K)], PNM4-[75% RDF: BDP (50% N, full dose of P and K)] and PNM5-[50% RDF: BDP (50% N, full P and K)]} assigned in sub-plots using a split-plot design with three replications. The remaining 50% N was top-dressed through SPAD assistance for all the PNM practices. Results showed that the adoption of Spr 80% ETC resulted in an increment of 25.6%, 17.6%, 35.4%, and 17.5% in net-photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), and intercellular CO2 concentration (Ci), respectively, over FI. Among PNM plots, adoption of PNM3 resulted in a significant (p=0.05) improvement in photosynthetic characters like Pn (15.69 µ mol CO2 m-2 s-1), Tr (7.03 m mol H2O m-2 s-1), Gs (0.175 µmol CO2 mol-1 year-1), and Ci (271.7 mol H2O m2 s-1). Enhancement in SPAD (27% and 30%) and normalized difference vegetation index (NDVI) (42% and 52%) values were observed with nitrogen (N) top dressing through SPAD-guided nutrient management, helped enhance crop growth indices, coupled with better dry matter partitioning and interception of sunlight. Canopy temperature depression (CTD) in soybean reduced by 3.09-4.66°C due to adoption of sprinkler irrigation. Likewise, Spr 60% ETc recorded highest irrigation water productivity (1.08 kg ha-1 m-3). However, economic water productivity (27.5 INR ha-1 m-3) and water-use efficiency (7.6 kg ha-1 mm-1 day-1) of soybean got enhanced under Spr 80% ETc over conventional cultivation. Multiple correlation and PCA showed a positive correlation between physiological, growth, and yield parameters of soybean. Concurrently, the adoption of Spr 80% ETC with PNM3 recorded significantly higher grain yield (2.63 t ha-1) and biological yield (8.37 t ha-1) over other combinations. Thus, the performance of SCI protocols under sprinkler irrigation was found to be superior over conventional practices. Hence, integrating SCI with sensor-based precision nutrient and irrigation management could be a viable option for enhancing the crop productivity and enhance the resource-use efficiency in soybean under similar agro-ecological regions.

12.
J Bioenerg Biomembr ; 44(1): 179-88, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22362056

RESUMO

The evolving role of mitochondria, in mediating chemotherapy-induced apoptosis motivated us for the studies described here. The combination of cisplatin and cyclophosphamide is widely used in treating various types of cancers. The purpose of our study was to understand the mechanism of the toxicity induced by the co-administration of cisplatin and cyclophosphamide, on mitochondrial bioenergetics, and to study the protective effect of prior administration of the medicinal plant extract Phyllanthus fraternus. Our results reveal that co-administration of cisplatin (12 mg/kg, i.p) and cyclophosphamide (150 mg/kg, oral) to wistar rats (100 g) significantly alters mitochondrial structure and hence function. The rate of mitochondrial respiration was decreased significantly with both NAD + and FAD-linked substrates. The respiratory control ratio, an index of membrane integrity and the P/O ratio, a measure of phosphorylating efficiency also were decreased significantly accompanied by elevation in the lipid peroxide levels in liver, kidney homogenate and liver mitochondria respectively. Also, the phospholipid content of the mitochondrial membrane, showed a significant decrease, indicating mitochondrial membrane changes. Prior administration of an aqueous extract of P. fraternus (100 mg/kg) to rats, showed protection on all parameters investigated. Administration of P. fraternus alone did not show any significant changes on mitochondrial membrane bioenergetics. Thus, we propose, that the toxic side effects of cisplatin (+) cyclophosphamide, are due to a chain of interconnected events, within the mitochondrial inner membrane, ultimately leading to hepatotoxicity and nephrotoxicity. Further, our work also suggests that administration of aqueous extract of P. fraternus can enhance the therapeutic potential of anticancer drugs by reducing drug related toxicity.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Ciclofosfamida/toxicidade , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Phyllanthus/química , Extratos Vegetais/farmacologia , Animais , Respiração Celular/efeitos dos fármacos , Cromatografia em Camada Fina , Peróxidos Lipídicos/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Consumo de Oxigênio , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar
13.
Transfus Apher Sci ; 47(3): 359-64, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22874437

RESUMO

BACKGROUND: The RBCs storage lesion is most carefully viewed as the sum of all the changes in RBCs occurring during the course of storage and that limit their survival. MATERIALS AND METHODS: Erythrocytes were isolated from stored blood at regular intervals. Oxidative stress markers were analyzed to determine the changes during the storage. RESULTS: Antioxidant enzymes--(SOD and CAT), and SH showed insignificant variation whereas hemolysis, MDA and AOPP showed significant variations. CONCLUSION: The oxidative stress has not successfully overridden the protection offered by the endogenous antioxidant system. Prolonged storage may result in the onset of erythrocyte deterioration. This clearly indicates that the erythrocytes are capable of attenuating ROS with 2 weeks of storage.


Assuntos
Bancos de Sangue/normas , Preservação de Sangue/métodos , Eritrócitos/citologia , Animais , Oxirredução , Estresse Oxidativo , Ratos , Ratos Wistar
14.
Biochem Mol Biol Educ ; 50(1): 75-90, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34741584

RESUMO

Gel electrophoresis (GE) is the most preferred and adapted technique for the separation and identification of biological molecules like proteins/peptides and nucleic acids from diverse types of organisms. All over the world, researchers, educators, and students aspiring to work in biochemistry and molecular biology disciplines use the polyacrylamide gel electrophoresis (PAGE) technique for resolving proteins/nucleic acids for understanding the structure and function of any cell. A simple PAGE technique requires a wide range of chemicals/reagents along with a well-equipped and well-spaced laboratory. We have developed a compact and impeccable mobile electrophoresis kit suitable for any vertically oriented PAGE technique. This comprehensive and portable laboratory set-up provides the complete advantages of safety, cost-efficiency, space management, and utility to the researchers for high-throughput research. All new equipment of the mobile electrophoresis kit is fabricated using inexpensive and off-the-rack components. Overall performance of the mobile kit was verified through a practical exercises executed by high school students with positive outcomes.


Assuntos
Ácidos Nucleicos , Proteínas , Eletroforese em Gel de Poliacrilamida , Humanos , Laboratórios , Proteínas/química , Estudantes
15.
Materials (Basel) ; 15(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35744178

RESUMO

The nanoparticles of CeO2, Ce0.98Fe0.02O2, and Ce0.78Fe0.02Cu0.20O2 were synthesized using the co-precipitation-synthesis technique. The effect of co-doping of Fe and Cu on structural, optical, and magnetic properties as well as specific capacitance have been studied using X-ray diffraction (XRD), scanning-electron microscopy (SEM), UV-visible spectroscopy, Raman spectroscopy, dc magnetization, and electrochemical measurements at room temperature. The results of the XRD analysis infer that all the samples have a single-phase nature and exclude the formation of any extra phase. Particle size has been found to reduce as a result of doping and co-doping. The smallest particle size was obtained to be 5.59 nm for Ce0.78Fe0.02Cu0.20O2. The particles show a spherical-shape morphology. Raman active modes, corresponding to CeO2, were observed in the Raman spectra, with noticeable shifting with doping and co-doping indicating the presence of defect states. The bandgap, calculated using UV-Vis spectroscopy, showed relatively low bandgap energy (1.7 eV). The dc magnetization results indicate the enhancement of the magnetic moment in the samples, with doping and co-doping. The highest value of saturation magnetization (1.3 × 10-2 emu/g) has been found for Ce0.78Fe0.02Cu0.20O2 nanoparticles. The electrochemical behavior studied using cyclic-voltammetry (CV) measurements showed that the Ce0.98Fe0.02O2 electrode exhibits superior-specific capacitance (~532 F g-1) along with capacitance retention of ~94% for 1000 cycles.

16.
Materials (Basel) ; 15(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36431441

RESUMO

Magnetic nanostructures of CoFe2O4 were synthesized via a microwave-assisted hydrothermal route. The prepared nanostructures were investigated using X-ray diffraction (XRD), field emission electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy, high-resolution transmission electron microscopy (HR-TEM), selective area electron diffraction (SAED) pattern, DC magnetization, and dielectric spectroscopy measurements. The crystal structure studied using HR-TEM, SAED, and XRD patterns revealed that the synthesized nanostructures had a single-phase nature and ruled out the possibility of any secondary phase. The lattice parameters and unit cell volume determined from the XRD data were found to be 8.4821 Å and 583.88 Å3. The average crystallite size (~7.0 nm) was determined using Scherrer's equation. The FE-SEM and TEM micrographs revealed that the prepared nanostructures had a spherical shape morphology. The EDX results showed that the major elements present in the samples were Co, Fe, and O. The magnetization (M) versus temperature (T) measurements specified that the CoFe2O4 nanostructures showed ferromagnetic ordering at room temperature. The blocking temperature (TB) determined using the M-T curve was found to be 315 K. The magnetic hysteresis (M-H) loop of the CoFe2O4 nanostructures recorded at different temperatures showed the ferromagnetic behavior of the CoFe2O4 nanostructures at temperatures of 200 K and 300 K, and a superparamagnetic behavior at 350 K. The dielectric spectroscopy studies revealed a dielectric constant (ε') and loss tangent (tanδ) decrease with the increase in the frequency, as well as demonstrating a normal dispersion behavior, which is due to the Maxwell-Wagner type of interfacial polarization. The values of ε' and tanδ were observed to increase with the increase in the temperature.

17.
Materials (Basel) ; 15(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36431669

RESUMO

In the present work, Cu-doped ZnO nanostructures (Cu% = 0, 1, 5) have been prepared using microwave-assisted chemical route synthesis. The synthesized nanostructures were investigated through structural, morphological, optical, and magnetic characterizations. The results of the X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and selective area electron diffraction (SAED) patterns confirmed that all of the samples exhibit the single-phase polycrystalline hexagonal crystal structure. The XRD results infer a decrease in the lattice parameters (a/c) by increasing the Cu% doping into ZnO. The field emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray (EDX) spectroscopic measurements revealed the formation of nanostructures, showing the major elemental presence of Zn and O in the samples. The photoluminescence (PL) spectra exhibited photoemission in the UV and blue-green regions. With the increase in the Cu%, the photoemission in the UV region is reduced, while it is enhanced in the blue-green region. Raman spectra of the Cu-doped ZnO nanostructures displayed a blue shift of the E2High mode and an increase in the peak intensity of E1(LO), indicating the doping of Cu ion in the ZnO lattice. The dc magnetization measurements demonstrated the ferromagnetic behavior of all of the samples with an enhanced ferromagnetic character with increasing Cu%.

18.
Materials (Basel) ; 15(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35744177

RESUMO

BiFe1−xCrxO3, (0 ≤ x ≤ 10) nanoparticles were prepared through the sol−gel technique. The synthesized nanoparticles were characterized using various techniques, viz., X-ray diffraction, high-resolution field emission scanning electron microscopy (HRFESEM), energy dispersive spectroscopy (EDS), UV−Vis absorption spectroscopy, photoluminescence (PL), dc magnetization, near-edge X-ray absorption spectroscopy (NEXAFS) and cyclic voltammetry (CV) measurements, to investigate the structural, morphological, optical, magnetic and electrochemical properties. The structural analysis showed the formation of BiFeO3 with rhombohedral (R3c) as the primary phase and Bi25FeO39 as the secondary phase. The secondary phase percentage was found to reduce with increasing Cr content, along with reductions in crystallite sizes, lattice parameters and enhancement in strain. Nearly spherical shape morphology was observed via HRFESEM with Bi, Fe, Cr and O as the major contributing elements. The bandgap reduced from 1.91 to 1.74 eV with the increase in Cr concentration, and PL spectra revealed emissions in violet, blue and green regions. The investigation of magnetic field (H)-dependent magnetization (M) indicated a significant effect of Cr substitution on the magnetic properties of the nanoparticles. The ferromagnetic character of the samples was found to increase with the increase in the Cr concentration and the increase in the saturation magnetization. The Fe (+3/+4) was dissolved in mixed-valence states, as found through NEXAFS analysis. Electrochemical studies showed that 5%-Cr-doped BFO electrode demonstrated outstanding performance for supercapacitors through a specific capacitance of 421 F g−1 measured with a scan rate of 10 mV s−1. It also demonstrated remarkable cyclic stability through capacitance retention of >78% for 2000 cycles.

19.
Front Plant Sci ; 13: 975569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212325

RESUMO

Photosynthesis, crop health and dry matter partitioning are among the most important factors influencing crop productivity and quality. Identifying variation in these parameters may help discover the plausible causes for crop productivity differences under various management practices and cropping systems. Thus, a 2-year (2019-2020) study was undertaken to investigate how far the integrated crop management (ICM) modules and cropping systems affect maize physiology, photosynthetic characteristics, crop vigour and productivity in a holistic manner. The treatments included nine main-plot ICM treatments [ICM1 to ICM4 - conventional tillage (CT)-based; ICM5 to ICM8 - conservation agriculture (CA)-based; ICM9 - organic agriculture (OA)-based] and two cropping systems, viz., maize-wheat and maize + blackgram-wheat in subplots. The CA-based ICM module, ICM7 resulted in significant (p < 0.05) improvements in the physiological parameters, viz., photosynthetic rate (42.56 µ mol CO2 m-2 sec-1), transpiration rate (9.88 m mol H2O m-2 sec-1) and net assimilation rate (NAR) (2.81 mg cm-2 day-1), crop vigour [NDVI (0.78), chlorophyll content (53.0)], dry matter partitioning toward grain and finally increased maize crop productivity (6.66 t ha-1) by 13.4-14.2 and 27.3-28.0% over CT- and OA-based modules. For maize equivalent grain yield (MEGY), the ICM modules followed the trend as ICM7 > ICM8 > ICM5 > ICM6 > ICM3 > ICM4 > ICM1 > ICM2 > ICM9. Multivariate and PCA analyses also revealed a positive correlation between physiological parameters, barring NAR and both grain and stover yields. Our study proposes an explanation for improved productivity of blackgram-intercropped maize under CA-based ICM management through significant improvements in physiological and photosynthetic characteristics and crop vigour. Overall, the CA-based ICM module ICM7 coupled with the maize + blackgram intercropping system could be suggested for wider adoption to enhance the maize production in semiarid regions of India and similar agroecologies across the globe.

20.
Front Microbiol ; 12: 643945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335488

RESUMO

The ultimate role of prokaryote (bacteria and archaea), the decomposer of the wetland ecosystem, depends on its community structure and its interaction with the environment. The present study has used three universal prokaryote primers to compare prokaryote community structure and diversity of three distinctly different wetlands. The study results revealed that α-diversity indices and phylogenetic differential abundance patterns did not differ significantly among primers, but they did differ significantly across wetlands. Microbial community composition revealed a distinct pattern for each primer in each wetland. Overall comparison of prokaryote communities in sediments of three wetlands revealed the highest prokaryote richness and diversity in Bhomra (freshwater wetland) followed by Malencho (brackish-water wetland) and East Kolkata wetland (EKW) (sewage-fed wetland). Indicator genus analysis identified 21, 4, and 29 unique indicator genera, having preferential abode for Bhomra, EKW, and Malencho, respectively. Prediction of potential roles of these microbes revealed a preference for sulfate-reducing microbes in Malencho and methanogens in Bhomra. The distinct phylogenetic differential abundance pattern, microbial abode preference, and their potential functional role predict ecosystem variables shaping microbial diversity. The variation in community composition of prokaryotes in response to ecosystem variables can serve as the most sensitive bioindicator of wetland ecosystem assessment and management.

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