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1.
Chemphyschem ; : e202300730, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38411619

RESUMEN

Prolonged exposure to alcohol vapors can have detrimental effects on human health, potentially leading to eye irritation, dizziness, and in some cases, damage to the nervous system. The present article aims to provide a comprehensive understanding on the synthesis and characterization of zinc ferrite (ZnFe2O4) nanoparticles, as well as their interactions with a range of alcohol vapors, including methanol, ethanol, n-propanol, and isopropanol. These alcohols differ in their molecular weight, boiling points, diffusivity, and other properties. The study reveals the semiconducting ZnFe2O4 nanoparticulate sensor's capability for reversible, repeatable, and sensitive detection of alcohol vapors. The sensor exhibits the highest response to ethanol within operating temperature range (225-300 °C). An attempt is made to establish a correlation between the properties of the target analytes and the observed sensing signals. Additionally, the response conductance transients of ZnFe2O4 under the exposure to the studied alcohol vapors are modeled based on the Langmuir-Hinshelwood adsorption mechanism. The characteristic time constants obtained from this modeling are justified with respect to the properties of the analytes.

2.
Trop Anim Health Prod ; 55(3): 211, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37204503

RESUMEN

Calf diarrhoea remains the biggest challenge both in the small and large farms. Infectious diarrhoea is associated with many pathogens, Escherichia coli being one, but majority are systematically treated with antibiotics. Since antimicrobial resistance (AMR) is a growing menace, the need to find alternative prophylactic solutions using popular kitchen herbs such as Trachyspermum ammi (carom seeds), Curcuma longa (turmeric) and cinnamon (Cinnamomum sp.) extracts is been investigated against virulent form of E. coli isolated from calf diarrhoea. The virulence factors identified in these isolates were ST (32.5%), LT (20%), eaeA (15%), stx1 (2.5%) and stx2 (5%) with the occurrence of the most common serogroups as O18 (15%) followed by O111 (12.5%). Highest resistance was seen with beta lactam + beta lactamase inhibitor (amoxicillin/clavulanic acid) followed by beta lactams (ampicillin, cefuroxime and cefepime). The zone of inhibition due to cinnamon (methanol) and carom seed (ethanol) extracts (500 to 250 µg/mL concentration) on E. coli bacteria was >19 mm, respectively. Turmeric, cinnamon and carom had the potency of inhibiting the pathogenic E. coli which maybe suggestive of its use in calf diets as prophylaxis against diarrhoea.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Animales , Antibacterianos/farmacología , Diarrea/prevención & control , Diarrea/veterinaria , Diarrea/epidemiología , Ampicilina/farmacología , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/prevención & control , Infecciones por Escherichia coli/veterinaria
3.
Environ Monit Assess ; 194(3): 205, 2022 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-35184230

RESUMEN

Soil carbon and its fractions are important in understanding the mechanism of soil carbon sequestration. The present study evaluated the impact of seven commercial bamboo species, viz., Bambusa balcooa, B. bambos, B. vulgaris, B. nutans, Dendrocalamus hamiltonii, D. stocksii, and D. strictus, on labile and non-labile carbon fractions. In the 0-15-cm layer, B. nutans had the highest very labile C (7.65 g kg-1) followed by B. vulgaris > B. balcooa > D. stocksii > D. hamiltonii > B. bambos > D. strictus > open. The active carbon pool was significantly low under the control plot (i.e. the open) indicating the positive influence of bamboo in soil C build-up in the top 0-15 cm soil layer. Amongst the different species of bamboo evaluated in this study, D. strictus accumulated the highest active C pool in 0-30-cm soil layer followed by B. vulgaris. Of the total organic C in the 0-30 cm soil depth, majority (55-60%) was contributed by the passive C pool comprising the less labile and the non-labile fraction of SOC. A high value of carbon stratification ratio (> 2) was observed for D. strictus, B. bambos, and D. hamiltonii which proves their potential for restoration of the degraded lands. The majority of bamboo species except for B. balcooa and D. stocksii showed a higher carbon management index than open systems, thereby indicating higher rates of soil C rehabilitation. Of the seven bamboo species, B. vulgaris, D. strictus, and B. nutans can be adopted for cultivation in the northwest Himalayas given their ability to positively impact the SOC and its fractions in both surface and sub-surface soil.


Asunto(s)
Carbono , Suelo , Carbono/análisis , Secuestro de Carbono , Monitoreo del Ambiente , India
4.
Bratisl Lek Listy ; 123(2): 110-119, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35065586

RESUMEN

Paracetamol is a popular and safe drug preferred by victims of pain or pyrexia; however, its overdose or abuse is a growing concern worldwide. Here the hepatoprotective effect of an ethnomedicinal plant Drynaria quercifolia against paracetamol­induced toxicity in murine model is demonstrated. This fern, native to tropical countries including the Northeast India, is used by local tribes to treat inflammatory conditions. Paracetamol 500 mg/kg body weight was orally administered on alternate days for a period of 21days to mimic a chronic overdose. Drynaria quercifolia acetone extract (DQA) treatment interspaced with paracetamol significantly decreased serum biomarkers of hepatotoxicity (ALT, AST and ALP) renal toxicity (urea, creatinine), lipid peroxidation level, histological damage in liver and kidney. The protein and mRNA expressions of the transcription factor, Nrf2, and its target antioxidant genes (SOD1, CAT and GST) as well as activities of these antioxidant enzymes were downregulated by paracetamol administration but significantly recovered following the DQA treatment (Tab. 3, Fig. 5, Ref. 31). Keywords: acetaminophen/paracetamol, Drynaria quercifolia, renal toxicity, hepatotoxicity, Nrf-2.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Polypodiaceae , Acetaminofén/toxicidad , Animales , Antioxidantes/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Hígado , Ratones , Extractos Vegetales/farmacología
5.
Kathmandu Univ Med J (KUMJ) ; 20(77): 66-69, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36273294

RESUMEN

Background Increase in common bile duct diameter can occur because of different causes. Post cholecystectomy status is one of the potential causes. Many studies done in the past show different results and are hence inconclusive. Objective To see if the post cholecystectomy cases would have a statistically significant change in common bile duct diameter. Method We carried out a study in 100 cases (46 post cholecystectomy cases and 54 cases with intact gall bladder, measuring their common bile duct diameters and performing an unpaired t test to see if the mean in common bile duct among these two groups of cases was statistically significant. Result One hundred cases, 46 post cholecystectomy cases and 54 cases with intact gall bladder were included in our study. An unpaired t-test was used to compare the common bile duct diameters in these two groups. Our findings showed that the difference in common bile duct diameter between the cases with intact gall bladder and those who underwent cholecystectomy was significant for both one tailed and two tailed studies (p < 0.001). Hence, it can be stated that post cholecystectomy status increases the common bile duct diameter. Conclusion An increased Common bile duct diameter in post cholecystectomy case could be because of the post cholecystectomy status itself and not due to some other obstructive cause. So careful decision is necessary before subjecting the patient to further invasive/non-invasive investigations and treatments.


Asunto(s)
Colecistectomía , Conducto Colédoco , Humanos , Conducto Colédoco/diagnóstico por imagen , Ultrasonografía
6.
Environ Monit Assess ; 193(8): 468, 2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-34226956

RESUMEN

Bamboos due to high soil water conservation potential are gaining increased attention in plantation programs across the globe. Large-scale plantation of fast-growing bamboo, however, can have important hydrological consequences. The study aims to quantify the eco-hydrological parameters, viz., throughfall (TF), stemflow (SF), and interception (I) in seven important sympodial bamboo species in north western Himalayan foothills of India. The species selected include Bambusa balcooa, Bambusa bambos, Bambusa vulgaris., Bambusa nutans, Dendrocalamus hamiltonii, Dendrocalamus stocksii, and Dendrocalamus strictus. Throughfall versus gross rainfall (GR) relationship in different species indicated high throughfall production during high rainfall events with r2 > 0.90. Average throughfall was lowest (62.1%) in D. hamiltonii and highest in B. vulgaris (74.6%). SF ranged from 1.32% in B. nutans to 3.39% in D. hamiltonii. The correlation coefficient (r) between leaf area index (LAI), number of culms, and crown area with the interception were 0.746, 0.691, and 0.585, respectively. The funneling ratio (F) was highest (27.0) in D. hamiltonii and least in B. nutans. Canopy storage capacity was highest in D. strictus (3.57 mm) and least in D. hamiltonii (1.09 mm). Interception loss was highest (34.4%) in D. hamiltonii and lowest in B. vulgaris (23.5%) and D. strictus (23.6%). Higher interception in bamboos make them suitable for soil conservation, but careful selection of species is required in low rainfall areas.


Asunto(s)
Antozoos , Monitoreo del Ambiente , Animales , Hidrología , India , Suelo
7.
Trop Anim Health Prod ; 52(4): 1759-1767, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31898029

RESUMEN

To find out the effect of reducing energy intake during dry period on milk production, udder health, and body condition, the experiment was conducted on 14 Jersey crossbred cows during whole dry period and continued up to 120 days of lactation. Reduction in energy intake was done during far-off period for each dry cow of treatment group as compared to control group. Statistically analyzed data revealed that overall significantly (P < 0.01) lower DMI and WI were recorded in control than treatment group. Overall significantly (P < 0.01) higher total milk production was found in treatment than control group. Overall significantly (P < 0.01) lower milk SCC, MCMT, pH, and EC were found in treatment than control group. Nonsignificant difference in milk fat, SNF, total solid, total protein, and fat:protein ratio was found. Overall significantly (P < 0.01) better quality milk (MBRT) was found in treatment than control groups. BCS during dry period and at calving was significantly (P < 0.01) different between groups. Significantly (P < 0.01) higher plasma NEFA concentration was estimated in control than treatment groups in all stages. No significant difference was found for plasma concentrations of glucose, urea, and total protein. The coefficients of correlation indicated significant (P < 0.01) correlation among BCS, milk production, milk SCC, MCMT, pH, and EC. It can be concluded that reducing energy intake during far-off dry period can lead to achieve optimum BCS at calving. Suitable BCS at calving was beneficial to get higher milk production with improved quality, better maintenance of udder health and body condition of Jersey crossbred cows at tropical lower Gangetic region.


Asunto(s)
Bovinos/fisiología , Dieta/veterinaria , Metabolismo Energético/fisiología , Glándulas Mamarias Animales/fisiología , Leche/fisiología , Alimentación Animal/análisis , Animales , Bovinos/genética , Ingestión de Energía , Femenino , Lactancia
8.
Kathmandu Univ Med J (KUMJ) ; 15(57): 71-74, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29446367

RESUMEN

Background Craniocerebral trauma is common health problem in emergency department of any hospital. CT is commonly indicated to to rule out any significant intracranial abnormalities in these patients, so that timely intervention of the significant intracranial pathologies can be done. Objective The study is done to evaluate CT findings of head injury patients in Dhulikhel Hospital. Method This prospective hospital based study was done in Department of Radiology of Dhulikhel Hospital in the period of January 2015 to December 2015. CT findings of the head trauma patients undergoing CT in the Department of Radiology were reviewed and analysed. Result The study was done in 484 patients, 165 female and 319 male patients. Mean age of the patients was 30.87 ± 19.25 years. Among them 205 patients showed abnormal CT findings, scalp injury being the commonest one, followed by skull fracture. 60 patients showed abnormal intracranial findings. There was significant correlation of skull fracture and abnormal intracranial findings in this study. Conclusion This study provided the normal and abnormal CT findings in head of the craniocerebral trauma patients in Dhulikhel Hospital. Abnormal CT findings were predominantly extra-cranial and were overlapping with intracranial abnormal findings.


Asunto(s)
Traumatismos Craneocerebrales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Niño , Servicio de Urgencia en Hospital , Femenino , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Cuero Cabelludo/lesiones , Fracturas Craneales/diagnóstico por imagen , Adulto Joven
9.
Kathmandu Univ Med J (KUMJ) ; 14(56): 357-361, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29336425

RESUMEN

Background Appendix is a blind-ended tubular structure arising from caecum, with variable intraluminal contents and position. Acute appendicitis is one of the common indications for emergency radiological investigation. Objective To assess visualization rate, size and position of normal appendix by Computed Tomography (CT). Method This cross-sectional observational study was done in 198 individuals undergoing abdominal CT without suspicion of acute appendicitis and without any pathology localized within right iliac fossa. Axial and coronal reformatted images of nonenhanced and contrast enhanced CT of abdomen were evaluated for visualization of appendix. Visualized appendices arising from caecum were traced and tip localized. Contents within the appendicular lumen were also evaluated and maximum transverse diameter of appendix measured. The relationship between appendicular diameter, intraluminal content and position with different age groups & gender were also derived. Result Visualization rates of appendix were 90% (93% male and 87% female) in nonenhanced CT and 97% (99.8% male and 95.4% female) in enhanced CT. The mean diameter of the appendix was 6.2 ± 1.16 mm. Most common location of the tip of appendix was pelvic position, followed by retrocaecal position. Most of the appendices showed intraluminal air. Conclusion Multi-Detector Computed Tomography is superior over ultrasonography (USG) in detection of appendix. Modifications of CT protocol reduce limitations of CT over ultrasound in evaluation of appendix. Ultrasound size criteria for appendicitis (>6 mm) is not applicable in CT as normal appendix can measure >6 mm in CT.


Asunto(s)
Apéndice/anatomía & histología , Apéndice/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Medios de Contraste , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto Joven
10.
Reprod Domest Anim ; 50(3): 505-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25845404

RESUMEN

Mammalian circadian locomotor output cycles kaput (CLOCK) gene encodes a transcription factor that affects both the persistence and the period of circadian rhythms. Earlier reports suggested that CLOCK gene might be associated with male infertility in human. Present investigation, for the first time, reports that CLOCK gene expresses differentially between good and poor quality crossbred bull semen. The relative expression of CLOCK was significantly (p < 0.05) higher among good quality bull semen than motility-impaired ones. Clusterins (CLU) are series of genes associated with a variety of physiological activities including spermatogenesis, apoptosis and degenerative disease conditions. In the present context, we also investigated that the expression of CLU gene was significantly (p < 0.05) higher among motility-impaired crossbred bull semen compared to the good quality one.


Asunto(s)
Proteínas CLOCK/metabolismo , Bovinos/fisiología , Clusterina/metabolismo , Regulación de la Expresión Génica/fisiología , ARN Mensajero/metabolismo , Espermatozoides/metabolismo , Animales , Proteínas CLOCK/genética , Bovinos/genética , Células Cultivadas , Clusterina/genética , Masculino , ARN Mensajero/genética , Motilidad Espermática
11.
Chem Asian J ; 19(2): e202300841, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38100152

RESUMEN

Detection of gas molecules and volatile organic compounds (VOCs) using efficient, low cost sensors has fetched significant attention in environmental monitoring, safety measures and medical diagnosis. In the present work, nickel ferrite (NFO) nanoparticles are explored as p-type semiconducting metal oxide (SMO) sensor for detection of five different organic vapors namely methanol, ethanol, n-propanol, iso-propanol and acetone which often cause severe damage to human body under prolonged exposure. The sensing studies in presence of the aforementioned five vapors are carried out by varying the sensor operating temperature (225-300 °C) and vapor concentrations (10-1000 ppm). Developed NFO sensor demonstrated best performance in terms of sensing (~10 ppm), response time (<10 s), excellent repeatability and selectivity towards ethanol among all other considered gas species. The repeatability of the sensor response is verified and the underlying reasons for the variation in the response of NFO sensor due to the change of operating temperature, analyte type and concentrations has been discussed. The synthesis of NFO through auto combustion method and study on their formation behaviour, oxygen vacancy evolution, band gap calculation, crystalline nature as well as microstructural features provides here the comprehensive information about the potential application of NFO nanoparticles as gas sensor.

12.
ScientificWorldJournal ; 2013: 320489, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23844390

RESUMEN

In this paper, opposition-based harmony search has been applied for the optimal design of linear phase FIR filters. RGA, PSO, and DE have also been adopted for the sake of comparison. The original harmony search algorithm is chosen as the parent one, and opposition-based approach is applied. During the initialization, randomly generated population of solutions is chosen, opposite solutions are also considered, and the fitter one is selected as a priori guess. In harmony memory, each such solution passes through memory consideration rule, pitch adjustment rule, and then opposition-based reinitialization generation jumping, which gives the optimum result corresponding to the least error fitness in multidimensional search space of FIR filter design. Incorporation of different control parameters in the basic HS algorithm results in the balancing of exploration and exploitation of search space. Low pass, high pass, band pass, and band stop FIR filters are designed with the proposed OHS and other aforementioned algorithms individually for comparative optimization performance. A comparison of simulation results reveals the optimization efficacy of the OHS over the other optimization techniques for the solution of the multimodal, nondifferentiable, nonlinear, and constrained FIR filter design problems.


Asunto(s)
Algoritmos , Almacenamiento y Recuperación de la Información/métodos , Procesamiento de Señales Asistido por Computador
13.
Ultrason Sonochem ; 100: 106607, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37748264

RESUMEN

Sonochemical recovery of radioactive contaminants from nuclear graphite has been demonstrated to be quite invaluable in recent studies. However, graphite is a soft material and is prone to erosion and wear. This restricts the recycle of graphite cleaned using ultrasound beyond a few decontamination cycles. Hence, it is an imperative to prevent the surface erosion of graphite in the sonic field. The current work studies the efficacy of ultrasound in decontaminating ceria contaminated graphite coupons using a cocktail of acids (0.25 M HNO3 - 1 M HCOOH - 0.2 M [N2H5][NO3]). Based on the superlative effects of ionic liquids in lubrication and erosion prevention, the effect of adding ionic liquid stabilized Pd nanoparticles to the leachate was also studied. It was observed that the Trioctylmethyl ammonium chloride (TOMAC) ionic liquid prevented the generation of the carbon residue due to a protective viscous layer formation reducing the mechanical effects of cavitation on graphite surface. It also helped in maintaining the porosity change in graphite microstructure around 5% after 15 cycles of decontamination. TOMAC also proved to offer better surface protection on graphite compared to imidazolium-based ILs, based on the change in compressive strength and porosity in different ionic liquids. The palladium nanoparticles, on the other hand, helped in reductive dissolution of ceria layer by acting as a reducing agent due to its lower reduction potential compared to cerium. With the surge in demand of graphite worldwide, a non-destructive decontamination process for graphite with no secondary waste generation is the need of the hour. This study is an attempt in that direction.

14.
ISA Trans ; 125: 614-630, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33012536

RESUMEN

The main objective of this paper is to improve the identification efficiency of non-linear systems using the Kalman filter (KF), which is optimised with the Artificial Electric Field (AEF) algorithm. The conventional KF suffers from the proper tuning of its parameters, which leads to a divergence problem. This issue has been solved to a great extent by the meta-heuristic AEF algorithm assisted Kalman filter (AEF-KF). This paper proposes three steps for the identification of the systems while solving the problem as mentioned above. Firstly, it converts the identification model to a measurement problem. Next, the AEF algorithm optimises the KF parameters by considering the fitness function with the KF equations. The third step is to identify the model using conventional KF algorithm with the optimised KF parameters. To evaluate the performance of the proposed method, parameter estimation error, mean squared error (MSE), fitness (FIT) percentage, statistical information and percentage improvement are considered as the performance metrics. To validate the performance of the proposed method, five distinct non-linear models are identified with the Volterra model using KF and the AEF-KF techniques under various noisy input conditions. Besides, the practical applicability of the proposed approach is also tested on two non-linear benchmark systems using experimental data sets. The obtained simulation results confirm the efficacy and robustness of the proposed identification method in terms of the convergence speed, computational time and various performance metrics as compared to KF, Kalman smoother (KS) which is optimised using different state-of-the-art evolutionary algorithms and also other existing recently reported similar types of stochastic algorithms based approaches.

15.
Ultrason Sonochem ; 82: 105863, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34896908

RESUMEN

Use of ultrasound as an intensified non-destructive decontamination technique for processing graphite limits its reusability beyond a few number of decontamination cycles due to the exfoliation of graphite due to cavitation effects. The current work establishes that the use of platinum nanoparticles in the leachant reduces the erosion of graphite substrate due to cavitation. It presents an improved way of sonochemical recovery of ceria using a mixture of nitric acid, formic acid and hydrazinium nitrate in the presence of platinum nanoparticles and ionic liquid. The platinum nanoparticles catalyst in ionic liquid prevented the generation of the carbon residue due to the combined effect of denitration and reduced sonication. The presence of the catalyst showed a fivefold increase in dissolution kinetics of ceria as well as absence of graphite erosion, facilitating better chances of graphite recycling than the decontamination without the catalyst. The catalytic approach offers a better recycle strategy for graphite with reduced exfoliation and NOx generation due to denitration, making it a more sustainable decontamination process. Since ceria is used as a surrogate for plutonium oxide, the results can be extended to decontaminate such deposits clearly establishing the utility of the presented results in the nuclear industry.

16.
J Environ Radioact ; 234: 106623, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34004408

RESUMEN

It is imperative to control radio-iodine discharges to atmosphere from nuclear reprocessing plants. Inhalation and ingestion of radio-iodine cause its concentration in the thyroid gland leading to risk of thyroid cancer in humans. Two isotopes of iodine viz. iodine-131 (131I) and iodine-129 (129I) are generated in considerable quantities in the nuclear fuel as fission products in the nuclear reactors. From nuclear reactors, no iodine is released to the atmosphere during normal operations, whereas from spent fuel reprocessing plants, during normal operation, iodine is discharged to the atmosphere, mainly through gaseous discharges. Shortly after the initial periods of reprocessing in 1944, iodine emission control methods were incorporated in the design of reprocessing plants. At the time of spent fuel discharge from reactor, quantity of 131I is high and can contribute radiation dose to humans during reprocessing operations. A delay or cooling period of spent fuel, before reprocessing for a definite number of days can reduce the quantities to below the permissible limits of discharge due to its short half-life of 8 days. 129I has a very long half-life, and is only significant for reprocessing plants of large throughput and high fuel burn-ups. Minimum required de-contamination factor (DF) for iodine for a reprocessing plant can be estimated from the limits of discharge of iodine stipulated by regulatory authority of each country. Though many processes were developed and demonstrated extensively in lab and pilot scale, only a few of these processes were found to be suitable for commercial deployment. This paper reviews systematically the operation experiences and performance characteristics of iodine control methods implemented so far. The review also focus on the effect of integrating various iodine control methods on the main reprocessing operations and thereby facilitate selection of the optimum iodine control method.


Asunto(s)
Contaminantes Radiactivos del Aire , Monitoreo de Radiación , Contaminantes Radiactivos del Aire/análisis , Atmósfera , Humanos , Reactores Nucleares
17.
Ultrason Sonochem ; 76: 105667, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34265634

RESUMEN

Use of nanomaterials to remove uranium by adsorption from nuclear wastewater is widely applied, though not much work is focused on the recovery of uranium from the sorbents. The present work reports the recovery of adsorbed uranium from the microstructures of silica nanoparticles (SiO2M) and its functionalized biohybrid (fBHM), synthesized with Streptococcus lactis cells and SiO2M, intensified using ultrasound. Effects of temperature, concentration of leachant (nitric acid), sonic intensity, and operating frequency on the recovery as well as kinetics of recovery were thoroughly studied. A comparison with the silent operation demonstrated five and two fold increase due to the use of ultrasound under optimum conditions in the dissolution from SiO2M and fBHM respectively. Results of the subsequent adsorption studies using both the sorbents after sonochemical desorption have also been presented with an aim of checking the efficacy of reusing the adsorbent back in wastewater treatment. The SiO2M and fBHM adsorbed 69% and 67% of uranium respectively in the second cycle. The adsorption capacity of fBHM was found to reduce from 92% in the first cycle to 67% due to loss of adsorption sites in the acid treatment. Recovery and reuse of both the nuclear material and the sorbent (with some make up or activation) would ensure an effective nuclear remediation technique, catering to UN's Sustainable Development Goals.


Asunto(s)
Nanopartículas/química , Dióxido de Silicio/química , Sonicación , Uranio/química , Uranio/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Temperatura
18.
Ultrason Sonochem ; 73: 105520, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33773435

RESUMEN

Yttria coated graphite crucibles are widely used to handle molten refractory and radioactive metals like uranium and plutonium. However, the coated layer suffers damages like cracking and peeling off owing to thermal cycles. As a result, removal of the yttria layer from the graphite surface is essential to ensure reuse of the crucible and minimization of radioactive waste. The present work investigates intensified dissolution of yttria from the coated graphite samples using ultrasound as a non-destructive decontamination technique to recycle the graphite substrate. The optimum conditions established for maximum dissolution were 8 M as acid strength, frequency of 30 kHz, temperature of 45 °C and power density of 8 W cm-2 that resulted in maximum dissolution of 52% in 30 min. Use of an oxidant H2O2 to the acid, did not yield any improvement in the dissolution kinetics, instead, increased oxidation of the graphite substrate was observed, leading to the anomalous weight gain of the graphite substrate despite surface erosion. Effect of ultrasound on the dissolution was pronounced, with almost a threefold increase compared to dissolution performed under silent conditions. Rates of dissolution of yttria from the substrate of different densities and pore size distribution were also studied. The dissolution was slowest from graphite of density 1.82 g cm-3 as the pore size distribution was conducive to accommodate the yttria particles. The dissolution in nitric acid followed ash layer diffusion controlled kinetics. The study has demonstrated the efficacy of application of ultrasound for accelerated decontamination of graphite substrates.

19.
Br J Dermatol ; 162(6): 1180-5, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20331460

RESUMEN

These guidelines for the management of vulvodynia have been prepared by the British Society for the Study of Vulval Diseases Guideline Group. They present evidence-based guidance for treatment, with identification of the strength of evidence available at the time of preparation of the guidelines.


Asunto(s)
Vulvodinia/diagnóstico , Vulvodinia/terapia , Terapia por Acupuntura , Anestésicos Locales/uso terapéutico , Antidepresivos Tricíclicos/uso terapéutico , Dispareunia/diagnóstico , Dispareunia/etiología , Femenino , Humanos , Dimensión del Dolor/métodos , Disfunciones Sexuales Fisiológicas/diagnóstico , Disfunciones Sexuales Fisiológicas/etiología , Vulvodinia/complicaciones
20.
Int J STD AIDS ; 21(5): 317-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20498098

RESUMEN

The aim of this study is to gain an understanding of the services available to subjects of sexual assault at genitourinary medicine (GU medicine) clinics throughout the United Kingdom, and to determine whether these services are adequate. By means of a questionnaire, consultants in 106 clinics provided information on the number of patients who reported sexual assault and the services available to them. The study found a marked regional variation in attendances by subjects of sexual assault. However, only a minority of clinics kept accurate data (36.7% regarding female victims and 37.75% regarding male victims). The number of subjects who were aged under 16 years was disproportionately high (under 16s: 6.9% of female victims and 1.2% male victims; 16 and over: 1.3% of female victims and 0.14% of male victims). This survey highlights deficiencies in services that need to be addressed by clinics, management and the speciality.


Asunto(s)
Instituciones de Atención Ambulatoria/estadística & datos numéricos , Víctimas de Crimen/estadística & datos numéricos , Atención a la Salud , Delitos Sexuales , Adolescente , Femenino , Encuestas de Atención de la Salud , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Distribución por Sexo , Reino Unido
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