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1.
Nature ; 530(7589): 198-201, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26814971

RESUMO

The complex interplay of spin, charge, orbital and lattice degrees of freedom provides a plethora of exotic phases and physical phenomena. In recent years, complex spin topologies have emerged as a consequence of the electronic band structure and the interplay between spin and spin-orbit coupling in materials. Here we produce complex topologies of electrical polarization--namely, nanometre-scale vortex-antivortex (that is, clockwise-anticlockwise) arrays that are reminiscent of rotational spin topologies--by making use of the competition between charge, orbital and lattice degrees of freedom in superlattices of alternating lead titanate and strontium titanate layers. Atomic-scale mapping of the polar atomic displacements by scanning transmission electron microscopy reveals the presence of long-range ordered vortex-antivortex arrays that exhibit nearly continuous polarization rotation. Phase-field modelling confirms that the vortex array is the low-energy state for a range of superlattice periods. Within this range, the large gradient energy from the vortex structure is counterbalanced by the corresponding large reduction in overall electrostatic energy (which would otherwise arise from polar discontinuities at the lead titanate/strontium titanate interfaces) and the elastic energy associated with epitaxial constraints and domain formation. These observations have implications for the creation of new states of matter (such as dipolar skyrmions, hedgehog states) and associated phenomena in ferroic materials, such as electrically controllable chirality.

2.
AAPS PharmSciTech ; 23(5): 125, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474400

RESUMO

The accumulation of amyloid-beta at the neuronal sites is a major pathological hallmark involved in the etiology of Alzheimer's disease. To reduce the Aß-induced neuronal cytotoxicity, selenium nanoparticles and silymarin were fabricated in a single polysaccharide matrix for dual antioxidant and Aß fibril disaggregation activity. These nanoparticles were further stabilized by an exopolysaccharide xanthan gum. The nanoparticles were fabricated to reduce the amyloid-induced cytotoxicity in SH-SY5Y cells. A three-step method employing redox reaction of sodium selenite and ascorbic acid has been adopted for the synthesis of selenium nanoparticles. Consequently, xanthan gum powder was added to impart stability to the nanocarriers. The nanoparticles exhibited a particle size of 119.2 ± 2.8 nm, zeta potential of - 35.4 ± 3.8 mV, and % EE of 87.7 ± 2.23. HR-TEM with EDX analysis confirmed the presence of spherical nanoparticles. An in vitro drug release study exhibited 89.33 ± 5.4% release of silymarin from nanocarriers and was able to scavenge 90% free radicals of DPPH reagent. The thioflavin T (ThT) fibrillation kinetics study showed that the nanoparticles elicited maximum disaggregation of Aß fibrils that was depicted by the quenched fluorescence intensity signal. The cell viability results revealed that the highest neuroprotection activity was observed in the cell group treated with SLY-XG-Se against Aß 1-42-induced toxicity. The nanoparticles were able to internalize in SH-SY5Y cells. Our findings showed that the nanocarrier elicited anti-aggregation efficacy in neuronal cell lines and mitigated the Aß-induced cytotoxicity, which represents the prospects of neuroprotection involved in the therapeutics of AD.


Assuntos
Selênio , Silimarina , Amiloide , Peptídeos beta-Amiloides/metabolismo , Polissacarídeos Bacterianos , Silimarina/farmacologia
3.
Phys Chem Chem Phys ; 23(32): 17479-17492, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34355708

RESUMO

Defect engineering in perovskites has been found to be the most efficient approach to manipulate their performance in ultraviolet-to-visible photon conversion. Under UV irradiation, BaSnO3 exhibited multicolor photoluminescence (MCPL) in the bluish white region. Its origin has not been well studied in the literature and has been probed in this work using synchrotron radiation, positron annihilation and density functional theory. To achieve desirable performance of doped BaSnO3 in optoelectronics, it is imperative to have correct information on the dopant local site, doping induced defect evolution and efficacy of host to dopant energy transfer (HDET). Extended X-ray absorption fine structure (EXAFS) showed that Eu3+ ions stabilize at both Ba2+ and Sn4+ sites consistent with the highly negative formation energy of around -6.26 eV. Eu3+ doping leads to an intense 5D0→7F1 orange emission and a feeble 5D0→7F2 red emission and an internal quantum yield (IQY) of ∼21% mediated by ET from the defect level of EuBa and EuSn sites to the valence band maximum (VBM). X-ray absorption near edge structure (XANES) ruled out any role of Sn2+ in the PL of BaSnO3 or Eu2+ in the PL of BaSnO3:Eu3+. Interestingly, when co-doped, Eu3+ stabilizes at Sn4+ sites whereas La3+ stabilizes at Ba2+ sites with a formation energy value of -6.44 eV. Based on the asymmetry ratio in emission spectra, it was found that La3+ ions lead to lowering of symmetry around Eu3+ due to increased vacancies and structural distortions, and also suppress the luminescence IQY. We have performed experimental positron annihilation lifetime spectroscopy (PALS) to probe the defects in BaSnO3 in pristine samples and on doping/co-doping. The positron lifetimes for saturation trapping of positrons in various kinds of defects envisaged in BaSnO3 and in the defect free system were calculated using the MIKA Doppler program. Such deep insight into the effect of local structures, dopant sites, defect evolution, ET, etc. on the optical properties of BaSnO3 is expected to provide very deep insight for material scientists into the fabrication of perovskite-based optoelectronic and light-emitting devices.

4.
Biologicals ; 69: 59-65, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33309531

RESUMO

Distressing effects on animal and human health with lethal progression, being used as bioweapon and shared features with non-pathogenic bacteria demands sensitive, specific, safe, cost effective and rapid detection methods for anthrax causing organisms. Conventional microbiology based diagnostics for anthrax are time consuming and need sophisticated equipment, while molecular diagnostics require less time and labor. The Loop mediated isothermal amplification assay (LAMP) is rapid, sensitive and specific assay and requires no specialized equipment. In the present study, we developed a LAMP assay for rapid as well as specific detection of Bacillus anthracis. The optimized assay produced positive results with the Sterne strain and one field isolate of B. anthracis and, negative results with other bacteria of the same and different genera within 2 h. Sensitivity was 500 fg of total DNA of B. anthracis, which was 100 times more sensitive than conventional PCR. The present study also demonstrated that the simple method of total DNA extraction by repeated boiling and freezing will not adversely affect the LAMP results. In conclusion, the optimized LAMP assay is a promising tool for the specific, sensitive, less time-consuming diagnosis for anthrax causing bacteria and also, for detecting the virulence of suspected B. anthracis cultures.


Assuntos
Antraz , Bacillus anthracis , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Animais , Antraz/diagnóstico , Bacillus anthracis/genética , Bacillus anthracis/isolamento & purificação , Humanos , Sensibilidade e Especificidade
5.
Indian J Public Health ; 65(Supplement): S18-S22, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33753587

RESUMO

BACKGROUND: A suspected food-poisoning outbreak occurred in a residential school in Mirzapur, India, in February, 2017. OBJECTIVE: We investigated the outbreak to find out the epidemiology and to identify the risk factors. METHODS: A descriptive study followed by retrospective-cohort study was done to investigate the outbreak. Cases (defined as ≥3 or more loose stools in 24 h, abdominal pain, or vomiting with onset between February 1 and 4, 2017) were searched by reviewing sick/patient registers from school and nearby health facilities. Cases were also searched through active surveillance by visiting school hostels. Stool samples were sent for microbiological testing. Food sources and food handlers were also assessed. RESULTS: Among 468 students, 204 cases were identified (44% attack rate) without any mortality. The median age was found to be 14 years (range: 10-18 years) and 59% were male. Relative risk with consumption of curd, apple, and panjiri (sweetened wheat flour) was found to be 15.4, 2.5, and 3.7, respectively. All these three food items were served as prasad, a religious offering. Only consumption of sweetened curd (adjusted odds ratio = 36.1, 95% confidence interval = 12.1-107.8) was significantly associated with gastroenteritis. No microorganism was isolated from two tested stool samples. Curd from the vendor was prepared from nonpasteurized milk. There were no illnesses among food-handlers. CONCLUSIONS: This outbreak of acute gastroenteritis in a residential school was associated with consumption of curd, likely contaminated with preformed toxins. We recommend implementation of the food safety and standards authority of India regulations.


Assuntos
Doenças Transmitidas por Alimentos , Gastroenterite , Adolescente , Criança , Estudos de Coortes , Surtos de Doenças , Farinha , Doenças Transmitidas por Alimentos/epidemiologia , Gastroenterite/epidemiologia , Humanos , Índia/epidemiologia , Estudos Retrospectivos , Instituições Acadêmicas , Triticum
6.
Med J Armed Forces India ; 77: S271-S277, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34334893

RESUMO

BACKGROUND: The first dose of the ChAdOx1 nCoV- 19 Corona Virus Vaccine (Covishield) was administered to the eligible beneficiaries of tertiary care institute of Western Maharashtra on 16 Jan 21 and in the past three months almost 97% of the staff has been vaccinated. The present study analyses the incidence of COVID cases in the unvaccinated and vaccinated population of the institute. METHODS: All Covid 19 infections (RT-PCR positive) from 01 February 21 to 25 April 21 were included in the study and analyzed as per their vaccination status. To assess the COVID 19 transmission in contacts, Secondary Attack Rates (SAR) of the pre-vaccination period (Jun-Oct 20) was compared with the present SAR. RESULTS: A total of 113 cases occurred in the study period (01 Feb to 25 Apr 21). Lower number of infections were observed among the fully vaccinated as compared to partially vaccinated and non-vaccinated. The overall vaccine effectiveness was found to be 88.6% (81.55-92.37) and 44.1% (4.55-67.3) in completely and partially vaccinated individuals respectively. Hazard Ratios for getting infected dropped significantly after 28 days of the second dose. The SAR in high risk contacts (HRCs) was found to be 4.25%, which was lower than SAR (20.6%) of pre-vaccination period. CONCLUSION: This is one of the earliest studies in India to report the impact of COVID-19 vaccination. The results indicate that the vaccine provides effective protection against COVID-19 infection. However, given the complex dynamics of vaccination, the role of NPIs and implementation of COVID appropriate behavior cannot be undermined.

7.
Environ Manage ; 65(6): 774-786, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32133539

RESUMO

In the Indo-Gangetic Plains of South Asia, the quadruple challenges of deteriorating soil quality, declining groundwater, energy shortages, and diminishing farm profitability threaten sustainability of conventional till (CT)-based cereal production systems. A 5-year study was conducted to evaluate the effect of conservation agriculture (CA)-based management (tillage, crop establishment, residue management, and system intensification through mungbean integration) on energy budget, water productivity, and economic profitability in cereal (rice-wheat, RW/maize-wheat, MW)-based systems compared with CT-based management. In CA systems, crop residues contributed the maximum (~76%) in total energy input (167,995 MJ ha-1); however, fertilizer application (nonrenewable energy source) contributed the maximum (43%) in total energy input (47,760 MJ ha-1) in CT-based systems. CA-based cereal (rice/maize) systems recorded higher net energy and energy-intensiveness (EI) levels of 251% and 300%, respectively, compared with those of the CT-based rice-wheat system (RW/CT) (295,217 MJ ha-1 and 46.05 MJ USD-1), irrespective of mungbean integration. MWMb/ZT+R utilized 204% more input energy, which resulted in 14% higher net energy and 229% higher EI compared with RW/CT. CA-based RW and MW systems enhanced the crop productivity by 10 and 16%, water productivity by 56 and 33%, and profitability by 34 and 36%, while saving in irrigation water by 38 and 32%, compared with their respective CT-based systems, respectively. CA-based system improved net energy, crop productivity, and profitability; therefore, it should be outscaled to improve the soil and environmental quality in north-west India.


Assuntos
Agricultura , Grão Comestível , Ásia , Fazendas , Solo
8.
Soil Tillage Res ; 199: 104595, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32362695

RESUMO

Climate smart agriculture (CSA) practices are emerging as sustainable alternative to conventional rice-wheat system to pull up natural resources degradation across south Asia. After five years of continuous CSA based experiment, a two years study was conducted to evaluate changes in microbial biomasses (microbial biomass carbon and nitrogen), enzyme activities (alkaline phosphatase, dehydrogenase and ß-glucosidase), nutrient release and uptake (N, P and K) at different wheat crop growth stages. Effect of CSA practices was also studied for carbon mineralization in an incubation experiment. Four scenarios (Sc) were included in this study- conventional tillage (CT) based rice-wheat system (Sc1), partial CSA based rice-wheat-mungbean system (Sc2), full CSA based rice-wheat-mungbean system (Sc3), and full CSA based maize-wheat-mungbean system (Sc4). Soil samples were collected from scenarios at 0-15 and 15-30 cm depth at different growth stages of wheat crop namely sowing, crown root initiation (CRI), active tillering, panicle initiation, and harvesting. Analysis of soil was done for chemical properties viz. pH, electrical conductivity, available N, P, K, NPK uptake and mineralizable carbon and biological properties viz., microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), dehydrogenase activity (DHA), alkaline phosphatase activity (APA) and ß-glucosidase. Significantly higher microbial biomass carbon (42 %) and nitrogen (79 %) were found in surface soil (0-15 cm depth) under CSA based scenarios (Sc2, Sc3 and Sc4) at harvest stage of wheat over CT based/ conventional scenario (Sc1). At surface soil, alkaline phosphatase, dehydrogenase and ß-glucosidase activity was 58, 14 and 13 % higher in CSA based scenarios, respectively than CT based scenario. CSA based scenarios showed significantly higher C mineralization after 3 days of the incubation experiment at harvest. An increase of respectively 15, 48 and 17 % of N, P and K uptake was observed with CSA based scenarios than CT based scenario. At harvest stage, 7 % higher amount of dry matter was reported with full CSA based scenarios (mean of Sc2 to Sc4) compared to Sc1. Higher wheat grain yield of ∼10 % was recorded with CSA based scenarios over CT based scenario. Therefore, CSA based scenarios with improved biological properties and nutrient availability and uptake at different wheat growth stages resulted in higher yields and hence need to be popularized among the farmers.

9.
Med J Armed Forces India ; 76(3): 276-283, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32773929

RESUMO

BACKGROUND: There is a deluge of information and misinformation about COVID-19. The present survey was conducted to explore the sources of information /misinformation for healthcare professionals from India. METHODS: A cross-sectional online survey using snowballing technique was conducted from 24 Mar to 10 Apr 2020. The questionnaire was pretested and developed using standard techniques. It was circulated among medical students and physicians. Data were analysed using the STATA software. RESULTS: Data of 758 participants were analysed. A total of 255 (33.6%) medical students, 335 (44.2%) nonspecialists and 168 (22.1%) specialists participated. The most common source of formal and informal information was official government websites and online news, respectively. A total of 517 (68.2%) participants accepted receiving misinformation. Social media and family and friends were the most common sources of misinformation. Seventy-two percent of participants agreed that spread of information helped to contain COVID-19, but more than that 75% agreed to having received inaccurate information. Seventy-four percent of respondents felt the need for regulation of information during such times; 26% and 33% felt that information about COVID-19 made them feel uncomfortable and distracts routine decision-making, respectively, and 50% felt it was difficult to differentiate correct from incorrect information about COVID-19. CONCLUSION: The study explored the sources of information and misinformation and found a high prevalence of misinformation, especially from social media. We suggest the need to better manage the flow of information so that it can be an effective weapon against SARS-CoV2. There is a need for doctors to adapt to the changing times of infodemics accompanying pandemics.

10.
Med J Armed Forces India ; 76(1): 84-88, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32020974

RESUMO

BACKGROUND: Acute kidney injury (AKI) is shown to be the commonest complication in critically ill children admitted to the pediatric intensive care unit (PICU). Kidney Disease: Improving Global Outcomes (KDIGO) classification and definition are now used universally. We undertook prospective observational study to study the etiology and maximum stage of AKI as defined by KDIGO and its complications and outcomes. METHODS: All children admitted to the PICU were included in the study. The diagnosis of sepsis and multiorgan dysfunction syndrome (MODS) was made according to the standard international guidelines. The patients were followed up till discharge/death. All children were screened for AKI at admission and subsequently using serum creatinine measured by modified Jaffe's method and urine output measurement. RESULTS: A total of 197 children were admitted to the PICU. 38 (19.28%) developed AKI, and 6 (15.78%) developed stage III AKI. Malignancies, serious neurological and renal disorders, and postsurgery complications accounted for most of the cases with AKI. Six were admitted with primary renal condition. Sepsis with or without MODS was seen in 12 patients with AKI and in 8 without AKI. Twenty-one children with AKI and 3 children without AKI were exposed to nephrotoxic drugs. Twenty-three children with AKI required inotropic support. The average length of stay (ALOS) of children with AKI in the PICU was 9.86 days, whereas ALOS of children without AKI was 6.23 days. Eighteen children with AKI (47.36%) and 36 (21.38%) with no AKI died. CONCLUSIONS: AKI in children in the PICUs of referral hospitals in the armed forces have varied etiologies and presentations. These children require early identification and management with close monitoring to prevent long-term renal morbidity and mortality.

11.
Phys Chem Chem Phys ; 21(11): 6198-6206, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30829355

RESUMO

The present work focuses on synthesis and X-ray absorption studies of single phase oxygen deficient anatase TiO2 thin films. These films are prepared in a two-step method viz. the synthesis of near stoichiometric anatase TiO2 films using an open atmospheric spray pyrolysis method followed by vacuum annealing at their corresponding synthesis temperatures (Ts = 450 °C, 500 °C) for different time durations (t = 2, 4, 6, 8 hours). XRD and Raman studies of these films ascertained the formation and retention of the anatase phase post annealing, indicating that there was no phase change due to prolonged annealing. Extended X-ray absorption spectra (EXAFS) and X-ray absorption near edge spectra (XANES) revealed the presence of an oxygen vacancy and its effect on the local co-ordination. The co-ordination number obtained from EXAFS analysis revealed that the number density of the oxygen vacancy is higher in the case of thin films synthesized at 450 °C than in the case of the films synthesized at 500 °C. As the oxygen vacancy leads to changes in local co-ordination, which in turn have a profound effect on the pre-edge features of the X-ray absorption spectra (XAS), theoretically simulated XAS spectra of pure anatase TiO2 and oxygen deficient anatase TiO2 were generated using FEFF and were found to match with the experimentally observed spectra. In addition, the ambiguities in whether a change in the metal-oxygen bond length has any effect on the pre-edge features or not were delineated in the present study by comparing the pre-edge peak positions of the oxygen deficient TiO2 films. Our results matched with those of some of the researchers who have studied the rutile phase TiO2, wherein it was concluded that in the case of the titanium-oxygen system, the mean Ti-O bond length does have an effect on the pre-edge peak position. It was observed that as the Ti-O mean bond length increases, the pre-edge peak positions shift towards lower energy, which is in concurrence with the literature available for other Ti-O systems with similar geometry. The second pre-edge peak intensity, which is a measure of disorder, is higher for TiO2450 °C-2 h and TiO2500 °C-2 h thin films. This is attributed to the annealing effect, which suggests that TiO6 octahedrons are the most disordered for thin films annealed for 2 h and become more ordered upon annealing for longer times.

12.
Phys Chem Chem Phys ; 21(3): 1294-1307, 2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30570634

RESUMO

Core-shell nanoparticles of Co (0%, 3%, and 5%) doped Ni/NiO and incorporated (5 mg) graphene oxide (GO) sheets were synthesized by a sol-gel auto-combustion method. X-ray absorption near edge structure (XANES), extended X-ray absorption fine structure (EXAFS) and pair distribution function measurements were employed for the determination of the local structure and structural properties of the samples. Due to the effect of Co doping the bond lengths of all coordinate atoms were varied. The microstructural features in the core-shell structured particles were evaluated with high-resolution transmission electron microscopy (HRTEM). Magnetic properties of the samples revealed that both the interface of Ni/Co and NiO crystal lattices and the weight fraction of Ni have significant impact on their magnetic properties at 5 K to 300 K. Experimental results show that Co doping and GO incorporation into Ni/NiO suppress the antiferromagnetic charge ordering and lead to a spin-flop metamagnetic behavior at 5 K to 300 K temperatures. Above 5 K, the step-like transitions transform into broad ones. This step-like feature is correlated with the collapse of the balance between the magnetic energy and elastic energy at the core-shell interface. It is confirmed from M-T measurements that the blocking temperature of Ni/NiO was reduced with Co content.

13.
J Appl Microbiol ; 126(3): 881-893, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30216609

RESUMO

AIM: Recent concerns about the possible adverse effects of agricultural chemicals on health and environment have generated a considerable interest in biological alternatives. This study aimed to test the insecticidal potential of fungus Aspergillus flavus and revealed its genotoxic and cytotoxic effects using Spodoptera litura (Fabricius) as a model. METHODS AND RESULTS: The fungus was isolated from the surface of the dead insect and investigated for its insecticidal potential against S. litura by bioassay studies. Significant increase in mortality, prolonged development period and reduced adult emergence in S. litura were observed in larva fed on diet supplemented with fungal extract. In addition, fungus was also found to cause oxidative stress, DNA damage and cell death. Significantly higher percentages of necrotic cells and DNA damage were observed in larvae treated with fungal extract. Furthermore, DNA repair studies predicted the longevity of toxic effects induced by fungus. Phytochemical and ultra-high performance liquid chromatography studies revealed the presence of phenolic compounds in the extract and liquid chromatography-mass spectrometry indicated it to be a non-aflatoxin strain of A. flavus. Fungal extract was less toxic to mammalian cell lines as compared to cytotoxic drug doxorubicin (DOX) in the MTT assay. CONCLUSION: The study highlights the insecticidal potential of A. flavus by revealing its genotoxicity and cytotoxicity causing potential. This is the first report showing the genotoxic and cytotoxic effects of the fungus A. flavus on S. litura. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides a useful insight to explore microbial agents as biopesticides in order to reduce various environmental as well as human health problems due to synthetic pesticides.


Assuntos
Aspergillus flavus , Produtos Biológicos/toxicidade , Citotoxinas/toxicidade , Mutagênicos/toxicidade , Spodoptera/efeitos dos fármacos , Acetatos , Animais , Larva/efeitos dos fármacos
14.
Soil Tillage Res ; 190: 128-138, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32055081

RESUMO

Intensive tillage based management practices are threatening soil quality and systems sustainability in the rice-wheat belt of Northwest India. Furthermore, it is accentuated with puddling of soil, which disrupts soil aggregates. Conservation agriculture (CA) practices involving zero tillage, crop residue management and suitable crop rotation can serve as better alternative to conventional agriculture for maintaining soil quality. Soil organic carbon is an important determinant of soil quality, playing critical role in food production, mitigation and adaptation to climate change as well as performs many ecosystem functions. To understand the turnover of soil carbon in different forms (Total organic carbon-TOC; aggregate associated carbon-AAC; particulate organic carbon- POC), soil aggregation and crop productivity with different management practices, one conventional agriculture based scenario and three CA based crop management scenarios namely conventional rice-wheat system (Sc1), partial CA based rice-wheat-mungbean system (Sc2), full CA-based rice-wheat-mungbean system (Sc3) and maize-wheat-mungbean system (Sc4) were evaluated. TOC was increased by 71%, 68% and 25% after 4 years of the experiment and 75%, 80% and 38% after 6 years of the experiment in Sc4, Sc3 and Sc2, respectively, over Sc1 at 0-15 cm soil depth. After 4 years of the experiment, 38.5% and 5.0% and after 6 years 50.8% and 24.4% improvement in total water stable aggregates at 0-15 and 15-30 cm soil depth, respectively was observed in CA-based scenarios over Sc1. Higher aggregate indices were associated with Sc3 at 0-15 cm soil depth than others. Among the size classes of aggregates, highest aggregate associated C (8.94 g kg-1) was retained in the 1-0.5 mm size class under CA-based scenarios. After 6 years, higher POC was associated with Sc4 (116%). CA-based rice/maize system (Sc3 and Sc4) showed higher productivity than Sc1. Therefore, CA could be a potential management practice in rice-wheat cropping system of Northwest India to improve the soil carbon pools through maintaining soil aggregation and productivity.

15.
Nat Mater ; 16(10): 1003-1009, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783161

RESUMO

Systems that exhibit phase competition, order parameter coexistence, and emergent order parameter topologies constitute a major part of modern condensed-matter physics. Here, by applying a range of characterization techniques, and simulations, we observe that in PbTiO3/SrTiO3 superlattices all of these effects can be found. By exploring superlattice period-, temperature- and field-dependent evolution of these structures, we observe several new features. First, it is possible to engineer phase coexistence mediated by a first-order phase transition between an emergent, low-temperature vortex phase with electric toroidal order and a high-temperature ferroelectric a1/a2 phase. At room temperature, the coexisting vortex and ferroelectric phases form a mesoscale, fibre-textured hierarchical superstructure. The vortex phase possesses an axial polarization, set by the net polarization of the surrounding ferroelectric domains, such that it possesses a multi-order-parameter state and belongs to a class of gyrotropic electrotoroidal compounds. Finally, application of electric fields to this mixed-phase system permits interconversion between the vortex and the ferroelectric phases concomitant with order-of-magnitude changes in piezoelectric and nonlinear optical responses. Our findings suggest new cross-coupled functionalities.

16.
Phys Chem Chem Phys ; 20(18): 13084-13091, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29714377

RESUMO

This article reports the detailed X-ray absorption spectroscopy (XAS) study of Al1-xCrxN (x = 4, 6, 11%) thin films synthesized by the reactive magnetron co-sputtering technique. All these films were crystallized with a hexagonal wurtzite structure with preferential orientation along the a-axis without the formation of any secondary phases. Surface chemical analysis to evaluate the Cr concentration was carried out using X-ray photoelectron spectroscopy. The study confirmed the presence of AlN and Cr in bonding with N. The local crystal structure around the Cr dopant in the as-synthesized and annealed thin films has been analyzed by both the X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) techniques. From XAS, it was found that Cr replaced the Al atom in the AlN lattice and led to a localized CrN species with distorted tetrahedral AlN in the absence of Cr clustering. The bond lengths of (Cr-N)ax, (Cr-N)bs and Cr-Al, extracted from the EXAFS fitting, were found to decrease with the Cr concentration for both the as-synthesized and annealed thin films due to the enhancement of p-d hybridization between the dopant and the host atoms. However, in the annealed 11% Cr film, the bond lengths are larger than the other and tend to match the Cr-N geometry in CrN.

17.
J Postgrad Med ; 64(2): 119-122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29067928

RESUMO

IgG4-related disease (IgG4-RD) is a multisystemic mass forming immune-mediated disease entity, commonly creating confusion and diagnostic challenges. We present a case of a 25-year-old female who presented with bilateral orbital masses, lymphadenopathy, paraspinal and renal masses, which clinicoradiologically simulated lymphoma. The lymph node biopsy revealed interfollicular sheets of plasma cells creating confusion with Castleman's disease and marginal zone lymphoma. The orbital biopsy revealed ductular destruction, periductular plasma cells, and fibrosis, mimicking Sjogren's syndrome and Castleman's disease. However, the correlation of the clinical features with histopathological findings, IgG4 immunopositivity, and serum studies helped in clinching the diagnosis. This case presents an uncommon combination of clinical features infrequently reported in literature. Furthermore, and more importantly, it highlights the need to keep a differential of IgG4-RD in mind, to aid early and correct treatment of the disease.


Assuntos
Doença Relacionada a Imunoglobulina G4/diagnóstico , Imunoglobulina G/sangue , Prednisolona/administração & dosagem , Administração Oral , Adulto , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Doença Relacionada a Imunoglobulina G4/tratamento farmacológico , Doença Relacionada a Imunoglobulina G4/patologia , Rim/diagnóstico por imagem , Linfadenopatia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Doenças Orbitárias/diagnóstico por imagem , Músculos Paraespinais/diagnóstico por imagem , Prednisolona/uso terapêutico , Biópsia de Linfonodo Sentinela , Tomografia Computadorizada por Raios X , Resultado do Tratamento
18.
Med J Armed Forces India ; 74(2): 103-107, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29692473

RESUMO

BACKGROUND: Nearly 1.5 billion adolescent girls are entering into child bearing age groups without effective knowledge regarding family planning practices which are essential to maintain their reproductive health. Timely and effective knowledge regarding family planning norms and practices among the young women during their initial married days are vital. Therefore the study was carried out with the aim to find out the factors associated with use of contraceptive among Armed Forces Personnel. METHODS: A cross sectional survey was carried out among Armed Forces personnel living in a Military station with pre-validated and pre-tested questionnaire. Data was collected from 221 eligible couples. Univariate and logistic regression were done to find out the variables determining family planning. RESULTS: Out of 221 couples, 65.2% (144) of couples were practicing some or the other methods of family planning while 34.8% (77) didn't practice any methods. Age, age at marriage, sex of first child, type of family, empowerment and parity of women were significantly associated with contraceptive acceptance in univariate model. However in logistic regression analysis age at marriage, empowerment and parity were significant predictors of family planning. Major reason for not adopting any contraception was want of another child (20, 26%), girl child (18, 23%), male child (18, 23%) and worry about side effects (11, 14.3%). CONCLUSION: The study highlights the gap in preferences and practices of contraceptive and emphasized the need to highlight safety of contraceptive during Information, Education and Communication (IEC) campaign.

19.
Med J Armed Forces India ; 74(1): 5-10, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29386724

RESUMO

BACKGROUND: Osteoporosis is associated with variable morbidity and socio-economic burden and referred as a "silent epidemic" with increasing risk among Indian women. The present study was conducted to find prevalence of osteoporosis. METHODS: A descriptive cross-sectional study was conducted in Ranchi city with household women as participants. Data was collected by means of pre-tested structured questionnaire in Hindi language and bone status was screened utilizing calcaneal quantitative ultrasound as a diagnostic tool to estimate bone mineral density from 223 participants and statistical analysis was performed with SPSS software. RESULTS: The mean age of the participants was 37.9 (5.63) and majority (52.5%) of them were vegetarian. The prevalence of osteoporosis was 8.5% (5.2-13%) while 45.7% (39-52.5%) had osteopenia. We found no significant association of osteoporosis and osteopenia with income, physical activity, and dietary patterns on univariate analysis. There was no statistical significant difference between mean age and BMI of participant among normal, osteoporosis, and osteopenia participant (p value >0.5). Multivariate logistic regression analysis shows that 20% increase chances of risk with five years increase in age, the protective effect of physical activity (22%) and non-vegetarian diet (18%) though not statistically significant. CONCLUSION: This study shows that significant number of women had osteopenia/osteoporosis within 35-40 years age group. Intensive information, education, and communication activities with regard to osteoporosis causative factors and preventive measures targeted to household women may play an important role, if started at young age.

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