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2.
Sci Rep ; 14(1): 7069, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528067

RESUMO

In this study, the efficacy of the combined effect of borate and silicate alkali metal salts added to mortars for controlling the chloride-induced uniform and localized corrosion of embedded steel rebars is examined. The individually added salts in mortars are found to have insignificant effects in terms of reducing the uniform corrosion rate and localized damage. However, their combination (0.50% sodium tetra borate + 0.10% sodium silicate added with respect to the weight of the binder) provides complete protection to reinforcements tested for long durations under wet/dry treatments with mortars in saline water and laboratory atmospheres. Electrochemical impedance spectroscopy, direct current cyclic polarization, polarization resistance, and visual observations are used for quantitative and qualitative evaluations of the protective effects of the tested additives. X-ray diffraction analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis of the corrosion products formed on the embedded steel surfaces help explain the possible mechanisms behind the considerable improvement in the inhibitive effects of a mixed composition of borate and silicate. This combination also improves the compressive strength and workability of the mixed concrete. The results reveal that the synergistic protection provided by a mixture of borate and silicate can be attributed to the co-deposition of an iron-boron + ferrosilicate + cortensitite (an iron-silicon phase) film on the rebar surface.

3.
Eye (Lond) ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066111

RESUMO

BACKGROUND: Understanding and mitigating the societal economic impact of vision impairment (VI) is important for achieving the Sustainable Development Goals. AIM: To estimate the prevalent societal economic impact of presenting VI in Trinidad and Tobago using bottom-up cost and utilisation data from the 2014 National Eye Survey of Trinidad and Tobago. METHODS: We took a societal perspective to combine comprehensive, individual-level cost and utilisation data, with population-based prevalence estimates for VI, and additional data from a contemporaneous national eyecare system survey. We included direct (medical and non-medical) and indirect (productivity loss) costs, and intangible losses in total cost estimates, presented in 2014 Trinidad & Tobago (TT) dollars and UK sterling equivalent. We considered but excluded transfer payments and dead weight losses. Sensitivity analyses explored impact on total cost of parameter uncertainty and assumptions. RESULTS: Individual utilisation and cost data were available for 65.5% (n = 2792/4263) and 59.0% (n = 2516/4263) eligible participants aged ≥40 years, respectively. Participant mean age was 58.4(SD 11.8, range 40-103) years, 56.3% were female. We estimated total societal cost of VI in 2014 at UK£365,650,241 (TT$3,842,324,655), equivalent to £675 per capita (population ≥40 years). Loss of wellbeing accounted for 73.3%. Excluding this, the economic cost was UK£97,547,222 (TT$1,025,045,399), of which indirect costs accounted for 70.5%, followed by direct medical costs (17.9%), and direct non-medical costs (11.6%). CONCLUSION: This study provides a comprehensive estimate of the economic impact of vision loss in a Caribbean country, and highlights the extent to which affected individuals and their families bear the societal economic cost of vision impairment.

4.
J Postgrad Med ; 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37787263

RESUMO

The developmental anomaly of the middle cerebral artery (MCA) is a rare occurrence. Rete MCA, also known as "unfused," "twig-like," and aplastic MCA, is an even rarer anomaly. These immature rete vessels are prone to flow-related aneurysms which rupture themselves presenting with intraparenchymal hematoma. We here with present a case of rete MCA with a ruptured aneurysm and discuss its pathophysiology and management.

5.
Opt Express ; 31(18): 29942-29953, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710783

RESUMO

Light propagation has been studied in photonic crystal fibers (PCFs) doped with W212 ferroelectric liquid crystal (FLC) composites with titanium dioxide nanoparticles (TiO2 NPs) of low concentrations between 0.2 and 1 wt. % in the FLC matrix. Optical microscopy observations indicated a slight increase of transition temperature to the isotropic phase by ∼1-2°C compared to the undoped FLC sample, and the TiO2 admixture was found to decrease free ionic charge impurities in the FLC, thus improving its electro-optical parameters. The switching time measurements in the PLCFs clearly indicate that TiO2 NPs reduce switching times for low electric field intensity, even by 32% compared to the undoped PLCF.

6.
J Environ Radioact ; 270: 107297, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37738760

RESUMO

The paper describes a new method for the rapid determination of Technetium (Tc) in sediment samples using solid-phase extraction chromatography (SPEC) with a novel methyl triphenyl phosphoniumnitrate (MTPN) resin. The effectiveness of the resin in selectively recovering Tc was evaluated in both batch and column mode and exploited for rapid analysis of 'Tc'. The procedure involves the acid digestion of samples, pre-concentration of fission products in supernatant and co-precipitation of actinides with Fe(OH)3, followed by selective recovery of Tc by SPEC using a column filled with MTPN resin. The recovered Tc was then radiometrically assayed using beta counting. The method was validated using IAEA certified reference materials and was found to provide reliable and reproducible results for the activity concentration of Tc-99 in sediment samples within 24 h.


Assuntos
Elementos da Série Actinoide , Monitoramento de Radiação , Tecnécio , Cromatografia
7.
Cureus ; 15(7): e41968, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37588321

RESUMO

BACKGROUND: Many individuals will also experience psychological side effects after a stroke episode, such as symptoms of depression, anxiety (generalized anxiety disorder (GAD)), and/or specific phobias, considerably decreasing their quality of life (QOL). OBJECTIVE: This study aimed to evaluate the prevalence of depression, obstructive sleep apnea (OSA), and concurrent anxiety (DOCA) and their outcomes (morbidity, disability (All Patient Refined Diagnosis Related Group (APRDRG) - loss of function), and discharge disposition) among acute ischemic stroke (AIS) hospitalizations. METHODS: A cross-sectional study used the National Inpatient Sample (NIS) from 2003-2017. Adults with hospitalizations with AIS were extracted, and DOCA was identified using ICD-9/10-CM codes. Weighted analysis using a chi-square test and mixed-effect multivariable survey logistic regression was used to assess the prevalence and role of DOCA in predicting outcomes. RESULTS: Out of 5,690,773 AIS hospitalizations, 2.7%, 3.1%, and 4.4% had depression, OSA, and GAD, respectively. In AIS patients, females had a higher prevalence of depression (3.4% vs. 2.3%) and GAD (5.9% vs. 3.0%) and a quality of life lower prevalence of OSA (2.2% vs 4.4%) in comparison to males (p<0.0001). Caucasians had a higher prevalence of depression, OSA, and GAD in comparison to others (African Americans/Hispanics/Asians/Native Americans). Depressed patients had a higher prevalence of morbidity (9% vs. 8% vs 5% vs. 7%), disability (46% vs. 46% vs. 35% vs. 37%), transfer to non-home (69% vs. 58% vs. 61% vs. 63%) in comparison with OSA, GAD, and non-DOCA patients, respectively (p<0.0001). Depression was associated with a 40% higher chance of severe disability (aOR 1.40; 95% CI 1.38-41), morbidity (1.36; 1.33-1.38), and discharge to non-home (1.54; 1.52-1.56). OSA and GAD had higher odds of non-home discharge amongst post-AIS hospitalizations. CONCLUSION: DOCA is associated with poor outcomes among post-AIS patients. Prompt recognition by screening and timely management of DOCA may mitigate the adverse outcomes.

8.
Nat Commun ; 14(1): 5212, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626129

RESUMO

Topological magnetic charges, arising due to the non-vanishing magnetic flux on spin ice vertices, serve as the origin of magnetic monopoles that traverse the underlying lattice effortlessly. Unlike spin ice materials of atomic origin, the dynamic state in artificial honeycomb spin ice is conventionally described in terms of finite size domain wall kinetics that require magnetic field or current application. Contrary to this common understanding, here we show that a thermally tunable artificial permalloy honeycomb lattice exhibits a perpetual dynamic state due to self-propelled magnetic charge defect relaxation in the absence of any external tuning agent. Quantitative investigation of magnetic charge defect dynamics using neutron spin echo spectroscopy reveals sub-ns relaxation times that are comparable to the relaxation of monopoles in bulk spin ices. Most importantly, the kinetic process remains unabated at low temperature where thermal fluctuation is negligible. This suggests that dynamic phenomena in honeycomb spin ice are mediated by quasi-particle type entities, also confirmed by dynamic Monte-Carlo simulations that replicate the kinetic behavior. Our research unveils a macroscopic magnetic particle that shares many known traits of quantum particles, namely magnetic monopole and magnon.

9.
Water Sci Technol ; 88(4): 991-1014, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37651334

RESUMO

Accurate Crop Evapotranspiration (ETc) estimation is crucial for understanding hydrological and agrometeorological processes, yet it's challenged by multiple parameters, data variations, and lack of continuity. These limitations restrict numerical methods application. To address this, the study aims to develop and assess ML models for daily maize ETc in semi-arid areas, utilizing varied weather inputs. Five ML models viz., Category Boosting (CB), Linear Regression (LR), Support Vector Machine (SVM), Artificial Neural Network (ANN), and Stochastic Gradient Descent (SGD) were developed and validated for the ICAR-IARI, New Delhi, Research Station. Penman-Monteith (PM) model estimated ETc values are used as the standard for comparing the performance of the ML model values. Results revealed that the SVM model achieved the highest coefficient of determination (R2) among all models, with a value of 0.987. Furthermore, the SVM model exhibited the lowest model errors (MAE = 0.121 mm day-1, RMSE = 0.172 mm day-1, and MAPE = 4.37%) compared to other models. The ANN model also demonstrated promising results, comparable to the SVM model. Notably, the wind speed parameter was found most influential input parameter. In conclusion, SVM or ANN could be considered reliable alternative methods for the accurate estimation of kharif maize crop ETc in the semi-arid climate.


Assuntos
Hidrologia , Zea mays , Modelos Lineares , Aprendizado de Máquina , Redes Neurais de Computação
10.
RSC Adv ; 13(13): 8551-8556, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36936828

RESUMO

Magnetic semiconductors are at the core of recent spintronics research endeavors. Chemically doped II-VI diluted magnetic semiconductors, such as (Zn1-x Cr x )Te, provide a promising platform in this quest. However, a detailed knowledge of the microscopic nature of magnetic ground state is necessary for any practical application. Here, we report on the synergistic study of (Zn1-x Cr x )Te single crystals using elastic neutron scattering measurements and density functional calculations. For the first time, our research unveils the intrinsic properties of ferromagnetic state in a macroscopic specimen of (Zn0.8Cr0.2)Te. The ferromagnetism is onset at T C ∼ 290 K and remains somewhat independent to modest change in the substitution coefficient x. We show that magnetic moments on Zn/Cr sites develop ferromagnetic correlation in the a-c plane with a large ordered moment of µ = 3.08 µ B. Magnetic moment across the lattice is induced via the mediation of Te sites, uncoupled to the number of dopant carriers as inferred from the density functional calculation. Additionally, the ab initio calculations also reveal half-metallicity in x = 0.2 composition. These properties are highly desirable for future spintronic applications.

12.
Environ Monit Assess ; 195(2): 279, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609939

RESUMO

Identifying suitable zones for surface water storage and groundwater recharge is needed to enhance irrigation water availability. This study was undertaken to map rainwater harvesting (RWH) potential zones using geospatial tools and analytic hierarchy process (AHP). The suitable locations for RWH were also mapped using the Boolean logic concept. The surface runoff is a vital factor to demarcate the appropriate zones for RWH. The curve number approach was used to estimate the surface runoff potential. The runoff coefficient (RC) map was generated based on rainfall and surface runoff depth. Weights have been allocated to selected themes of RC, drainage density, and slope. The themes were integrated using geographic information system (GIS) and AHP to demarcate the suitable zones for RWH. The derived RWH potential map was categorized into zones like "very good," "good," "moderate," "poor," and "very poor" with an aerial extent of 14.3%, 24.7%, 28.3%, 20.2%, and 12.6%, respectively. The area suitable for farm ponds was found to be about 9% (408 km2), 13% (329 km2), and 4% (244 km2) in Mirzapur, Chandauli, and Sonbhadra districts, respectively. Furthermore, 22, 15, and 21 locations were found suitable for check dams in Mirzapur, Chandauli, and Sonbhadra districts, respectively. At a large scale, effective planning of water management strategies based on multicriteria decision analysis and GIS offers increased availability of surface and groundwater resources and may help for enhancing the agricultural land use options. The higher resolution maps may be further utilized to plan RWH strategies at village level.


Assuntos
Sistemas de Informação Geográfica , Abastecimento de Água , Chuva , Monitoramento Ambiental , Água , Técnicas de Apoio para a Decisão
13.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 2): 2184-2189, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36452859

RESUMO

Eagle's Syndrome is a much discussed yet controversial and debatable diagnosis of exclusion which is treated by many specialities with often unsatisfactory results. Due to entrapment/impingement on surrounding neurovascular structures by elongated styloid process patient may present with multitude of symptoms. Treatment is controversial and opinions are divided on choice of conservative and surgical management. Aim was to study outcomes of conservative and surgical modalities of treatment of Eagle's Syndrome and bring some clarity on management, what to offer, to whom and when. This prospective observational descriptive study included 15 patients of Eagle's Syndrome, 7 were treated with conservative method and 8 underwent resection of styloid process with intraoral approach. With objectives in mind to study efficacy of both management modalities, pain visual analogue scale (VAS) scores were recorded pre-intervention, post-intervention and during follow up on 1, 3 and 6 months and compared. Conservative management resulted in up to 70% reduction in pain VAS scores till 3 months of therapy (mean pre-intervention score being 3.71, 3 months-1, 6 months-1.29), while surgical modality resulted in nearly 99% reduction in mean pain VAS scores up to 3 months and even improved after 6 months (mean pre-intervention score being 6.75, 3 months-0.5, 6 months-0.13). With this we can conclude that conservative management provide satisfactory short-term (up to 3 months) results but recurrences are known, while surgical resection of elongated styloid process gives better long-term results (6 months and beyond).

14.
Mymensingh Med J ; 31(4): 1153-1161, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36189566

RESUMO

In the past few decades, many medical professionals and dentists have paid close notice to their own fields, specializing in medicine pertaining to body and oral cavity respectively. Currently, this void is rapidly closing between all medical specialties, in presence of significant findings that supports association between periodontal disease and systemic conditions. Till now, some practitioners are not aware about the specialties of dentistry that results in improper referral practices. There are few studies on referral practice pertaining to periodontist, not with standing the fact that clear and effective communication between all health practitioners is essential for good practice. A cross-sectional study was carried out to assess the knowledge and awareness about systemic effects of periodontal disease among medical, dental and alternate medical practitioners and their referral practice to periodontist in Kanpur city. This cross-sectional study was carried out using self-reported questionnaire, distributed to 560 practitioners of various medical fields from January 2020 to August 2021. A total of 206(36.8%) Medical, 194(34.6%) Dentists and 160(28.6%) alternative practitioners participated in study. More than half participants agreed about relationship between periodontal diseases and Diabetes Mellitus, Cardio-VascularDisease and Adverse Pregnancy Outcomes. Among all 31.3% showed good knowledge level while 2.7% showed perfect level of practitioner's referral practice to periodontist. Dentists had statistically higher level of awareness compared to physicians. Referral practice to periodontist was deficit by medical and alternate medical practitioners despite of fact; they have good knowledge of relationship between periodontal disease and systemic health. Hence, interdisciplinary dental and medical training of practitioners is recommended.


Assuntos
Odontólogos , Doenças Periodontais , Estudos Transversais , Humanos , Doenças Periodontais/complicações , Doenças Periodontais/terapia , Encaminhamento e Consulta , Inquéritos e Questionários
16.
SAR QSAR Environ Res ; 33(9): 677-700, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36093620

RESUMO

The application of QSAR along with other in silico tools like molecular docking, and molecular dynamics provide a lot of promise for finding new treatments for life-threatening diseases like Type 2 diabetes mellitus (T2DM). The present study is an attempt to develop Monte Carlo algorithm-based QSAR models using freely available CORAL software. The experimental data on the α-amylase inhibition by a series of benzothiazole-linked hydrazone/2,5-disubstituted-1,3,4-oxadiazole hybrids were selected as endpoint for the model generation. Initially, a total of eight QSAR models were built using correlation intensity index (CII) as a criterion of predictive potential. The model developed from split 6 using CII was the most reliable because of the highest numerical value of the determination coefficient of the validation set (r2VAL = 0.8739). The important structural fragments responsible for altering the endpoint were also extracted from the best-built model. With the goal of improved prediction quality and lower prediction errors, the validated models were used to build consensus models. Molecular docking was used to know the binding mode and pose of the selected derivatives. Further, to get insight into their metabolism by living beings, ADME studies were investigated using internet freeware, SwissADME.


Assuntos
Diabetes Mellitus Tipo 2 , Relação Quantitativa Estrutura-Atividade , Benzotiazóis , Consenso , Humanos , Hidrazonas , Modelos Moleculares , Simulação de Acoplamento Molecular , Oxidiazóis , alfa-Amilases
17.
Arch. endocrinol. metab. (Online) ; 66(4): 466-471, July-Aug. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1403234

RESUMO

ABSTRACT Objective: Thyroid functions in the sick newborns may be altered in the first week of life. Transient hypothyroxinemia has been reported in these babies, which could be due to the immaturity of the hypothalamic-pituitary-thyroid axis or to acute illness. We conducted this study to estimate the incidence of hypothyroxinemia and determine its risk factors in sick term newborns. Materials and methods: We analyzed free T4 (FT4) and thyroid-stimulating hormone (TSH) levels in sick term neonates (≤7 days of life) admitted to the neonatal intensive care unit. FT4 and TSH levels were estimated in the first week of life in all the enrolled neonates (N = 98) and then repeated at 14-21 days of life in 46 babies. Risk analysis was conducted using univariate and multivariate logistic regression, and numerical data was compared using the Mann-Whitney U test and t-test. Results: Hypothyroxinemia was seen in 10 (10.2%) of the admitted term babies. Male gender, vaginal delivery, presence of hypoxic ischemic encephalopathy, and need for mechanical ventilation (>24 hours) were identified as risk factors. There was a significant negative linear correlation between FT4 level in the first week of life and duration of hospital stay. Conclusion: Hypothyroxinemia is common in sick term neonates.

18.
Sci Rep ; 12(1): 12449, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864189

RESUMO

This communication reports the effect of phosphorus (P) added in micro concentration range in steel on kinetics, mechanism and growth of passive film in contact of chloride contaminated concrete. Electrochemical impedance spectroscopy, direct-current polarization, mass loss and Raman spectroscopic techniques were used to arrive at the findings. The results showed that an intentional addition of P in steel (0.064%) makes it more prone to uniform and localized corrosion (about 1.1 and 1.7 times) than the steel having low phosphorus (< 0.016%, present as tramp element) exposed under wet/dry conditions in simulated pore solution added with chloride and in the absence of this ion. A similar effect is also noted for the rebars embedded in mortars. Identification of corrosion products formed on steel rebars surface by Raman spectroscopy reveals thermodynamically stable maghemite and goethite phases on the surface of low P content steel. Unstable phase of lepidocrocite is recorded on the surface of higher phosphorus steel rebars. The findings are discussed with experimental evidence and taking clues from the published literature to arrive at plausible mechanism for this behaviour.

19.
Arch Endocrinol Metab ; 66(4): 466-471, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35657132

RESUMO

Objective: Thyroid functions in the sick newborns may be altered in the first week of life. Transient hypothyroxinemia has been reported in these babies, which could be due to the immaturity of the hypothalamic-pituitary-thyroid axis or to acute illness. We conducted this study to estimate the incidence of hypothyroxinemia and determine its risk factors in sick term newborns. Materials and methods: We analyzed free T4 (FT4) and thyroid-stimulating hormone (TSH) levels in sick term neonates (≤7 days of life) admitted to the neonatal intensive care unit. FT4 and TSH levels were estimated in the first week of life in all the enrolled neonates (N = 98) and then repeated at 14-21 days of life in 46 babies. Risk analysis was conducted using univariate and multivariate logistic regression, and numerical data was compared using the Mann-Whitney U test and t-test. Results: Hypothyroxinemia was seen in 10 (10.2%) of the admitted term babies. Male gender, vaginal delivery, presence of hypoxic ischemic encephalopathy, and need for mechanical ventilation (>24 hours) were identified as risk factors. There was a significant negative linear correlation between FT4 level in the first week of life and duration of hospital stay. Conclusion: Hypothyroxinemia is common in sick term neonates.


Assuntos
Unidades de Terapia Intensiva Neonatal , Tiroxina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Fatores de Risco , Doenças da Glândula Tireoide , Tireotropina
20.
Theor Appl Genet ; 135(11): 3709-3734, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35665827

RESUMO

Crown rust, caused by Puccinia coronata f. sp. avenae (Pca), is a significant impediment to global oat production. Some 98 alleles at 92 loci conferring resistance to Pca in Avena have been designated; however, allelic relationships and chromosomal locations of many of these are unknown. Long-term monitoring of Pca in Australia, North America and elsewhere has shown that it is highly variable even in the absence of sexual recombination, likely due to large pathogen populations that cycle between wild oat communities and oat crops. Efforts to develop cultivars with genetic resistance to Pca began in the 1950s. Based almost solely on all all-stage resistance, this has had temporary benefits but very limited success. The inability to eradicate wild oats, and their common occurrence in many oat growing regions, means that future strategies to control Pca must be based on the assumption of a large and variable prevailing pathogen population with high evolutionary potential, even if cultivars with durable resistance are deployed and grown widely. The presence of minor gene, additive APR to Pca in hexaploid oat germplasm opens the possibility of pyramiding several such genes to give high levels of resistance. The recent availability of reference genomes for diploid and hexaploid oat will undoubtedly accelerate efforts to discover, characterise and develop high throughput diagnostic markers to introgress and pyramid resistance to Pca in high yielding adapted oat germplasm.


Assuntos
Avena , Avena/genética , Austrália
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