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1.
Sci Rep ; 14(1): 4914, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418505

RESUMO

This study examines the effect of Ground Granulated Blast Furnace Slag (GGBS) and steel fibers on the flexural behaviour of RC beams under monotonic loading. Various percentages of GGBS were used to substitute cement, namely 0%, 20%, 40%, 60%, and 80% and fibers were added to the concrete mix as 0%, 0.5%, 1%, and 1.5% of the volume of concrete. The load-deflection behaviour of GGBS-incorporated RC beams with fibers was compared with the control RC beam. Beams were tested under load control for 28 days and 180 days. The ultimate load of the GGBS-incorporated RC beam up to 40% cement replacement was found to higher than that of the control beam. The strength of concrete is reduced by 28% and 19% when cement was partially replaced by 80% of GGBS at 28 and 180 days, respectively, compared to control concrete without fibres. Further, the analytical load-deflection response of GGBS-incorporated RC beams was determined by using several codes of practice, namely, ACI 318-11(2011), CSA A23.3-04 (2004), EC-04 (2004), and IS 456 (2000). The Codal provisions were primarily based on the effective moment of inertia, Young's modulus, and modulus of rupture, stiffness, and cracking. Average load-deflection plots obtained from experiments were compared with the computed load-deflection of analytical studies. It was found that the analytically predicted load-deflection behaviour is comparable with the corresponding average experimental load-deflection response. Moment curvature relations were also developed for RC beams.

4.
Environ Res ; 200: 111428, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107284

RESUMO

Atrazine is a toxic herbicide whose alarming rate of contamination in the drinking water and wastewater poses a severe threat to the environment and human health. Here in this study, the graphene oxide (GO) nanosheets were prepared using Hummers' method with minor modification and studied as a potential adsorbent for atrazine removal from simulated wastewater. The spectroscopy and microscopic analysis confirmed the successful formation of GO with a multilayer structure resembling the crumpled sheets with random stacking. The Response Surface Methodology (RSM) employing Box Behnken design (BBD) was successfully developed to predict the optimal conditions for maximal atrazine removal as adsorbent dosage 121.45 mg/L; initial feed concentration 27.03 mg/L; temperature 27.69 °C, pH 5.37, and time 180 min. The atrazine adsorption onto GO was found to be higher in acidic pH and lower temperature. Density functional theory (DFT) calculation of adsorbent-adsorbate complex in the implicit solvent medium suggests adsorption affinity energy of -24.4 kcal/mol for atrazine. A careful observation of the molecules configuration and binding energy showed that the π-π interactions and hydrogen bonds played a significant role in the adsorption phenomena. Langmuir isotherm suited well to the adsorption process with a maximum adsorption capacity of 138.19 mg/g, at 318 K. The fitness of kinetic models for atrazine adsorption onto GO nanosheets were in following order Ho < Sobkowsk-Czerwi < Avrami model based on their correlation coefficient (R2) values. Reusability analysis showed that GO nanosheets could be effectively recycled using 0.01 N NaOH up to six cycles of atrazine removal. Thus, this study provided a theoretical and experimental basis for the potential application of GO nanosheets as a novel adsorbent for the removal of hazardous atrazine.


Assuntos
Atrazina , Poluentes Químicos da Água , Adsorção , Teoria da Densidade Funcional , Grafite , Humanos , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/análise
10.
Cir Pediatr ; 33(3): 137-142, 2020 Jul 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32657098

RESUMO

INTRODUCTION: Palate fistula is the most frequent complication following palatoplasty. The objectives of this study were: to describe the most widely used repair techniques; to study results and recurrence rate; to analyze potentially predictive recurrence variables; and to assess whether a specific technique is superior according to fistula size and location. MATERIALS AND METHODS: Retrospective study of patients undergoing palate fistula repair in 7 healthcare facilities from 2008 to 2018. All facilities had at least 20 new cases of cleft lift and palate annually (range: 20-80), with a fistula incidence of 14% (range: 1.5-20%). Minimum follow-up was 1 year. 8 variables were collected for statistical analysis purposes. RESULTS: 234 fistula patients underwent surgery. Most fistulas occurred in complete bilateral cleft lift and palate (Veau type IV). The most frequent location was the hard palate (Pittsburgh types IV and V (63.2%)), and fistulas were mostly large (42.1%) and medium (39.5%). The most frequent repair technique was re-palatoplasty (34.2%). Recurrence rate was 22%. The multivariate analysis demonstrated more recurrences in re-palatoplasty repaired type III fistulas in patients over 3 years old. CONCLUSION: A tendency towards using flap repair in large hard palate fistulas, re-palatoplasty in medium hard palate and soft and hard palate junction fistulas, and local flaps or re-palatoplasty in small fistulas at any location was observed. However, it could not be statistically demonstrated whether a specific repair technique was superior in different clinical situations.


INTRODUCCION: La fístula palatina es la complicación más frecuente tras una palatoplastia. Los objetivos de este estudio fueron: describir las técnicas de reparación más frecuentemente empleadas; estudiar los resultados y la tasa de recidiva; analizar posibles variables predictivas de recidiva y valorar la posible superioridad de una determinada técnica según el tamaño y la localización de la fístula. MATERIAL Y METODO: Estudio retrospectivo de pacientes operados de fístulas palatinas desde 2008 hasta 2018 en 7 centros. Todos operaban al menos 20 casos nuevos de fisuras labiopalatinas al año (rango 20-80) con una incidencia de fístulas de 14% (rango: 1,5-20%). El seguimiento mínimo fue de 1 año. Se recogieron 8 variables para el análisis estadístico. RESULTADOS: Se operaron 234 pacientes con fístulas. La mayoría ocurrieron en fisuras labiopalatinas bilateral completa (tipo IV de Veau). La localización más frecuente fue el paladar duro (tipos IV y V de Pittsburgh (63,2%) y la mayoría fueron grandes (42,1%) y medianas (39,5%). La técnica de reparación más frecuente fue la repalatoplastia (34,2%). La tasa de recidiva fue del 22%. El análisis multivariante mostró más recidivas en fístulas tipo III reparadas con repalatoplastia, en mayores de 3 años. CONCLUSION: Se observó una tendencia a utilizar más reparación con colgajo en fístulas grandes del paladar duro, repalatoplastia en fístulas medianas de paladar duro y de la unión, y colgajos locales o repalatoplastia en fístulas pequeñas en cualquier localización, pero no se pudo demostrar estadísticamente la superioridad de una técnica reparadora concreta en diferentes situaciones clínicas.


Assuntos
Fissura Palatina/cirurgia , Fístula Bucal/cirurgia , Palato Duro/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Fatores Etários , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Fístula Bucal/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Recidiva , Estudos Retrospectivos , Retalhos Cirúrgicos
13.
Community Dent Health ; 37(3): 205-215, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32227705

RESUMO

OBJECTIVE: Assess interventions and health outcomes in studies giving data on economic evaluation (EE) of school-based caries prevention. BASIC RESEARCH DESIGN: Systematic review. Both partial EE that included cost description, cost-outcome description, cost analysis and full EE that included both cost and outcome of at least 2 interventions were included. Quality assessment used the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) guidelines. RESULTS: An electronic search of 6 databases identified 558 titles and abstracts. Paper eligibility screening identified 32 full papers which met the inclusion criteria. Most were conducted in the United States and cost effectiveness analysis was the most common type of EE. Nine were model-based studies and 17 derived their data from single studies. Sealants were most frequently evaluated followed by fluoride mouthrinse. Many CHEERS criteria were not met in the included studies. The following were found to be cost-effective: school-based, under general supervision, longer duration of program and targeting high caries risk groups. CONCLUSIONS: The deficiencies in the existing studies warrant more investigations of the economic aspects of school-based activities interventions to prevent caries.


Assuntos
Cárie Dentária , Análise Custo-Benefício , Fluoretos , Humanos , Serviços de Saúde Escolar , Instituições Acadêmicas
14.
Rev Sci Instrum ; 91(2): 024101, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113421

RESUMO

Indigenous instrumentation has been designed and developed for the measurement of the concentration of analytes from eight conductometric metal oxide sensors. The hardware scheme of instrumentation is based on the astable multivibrator configuration. The hardware measures the resistance output from the sensors, conditions, processes, and displays the data on the liquid crystal display. An 8051 based processor averages the data, converts them into engineering units, and sends them to remote PC through ethernet communication for post-data analysis. A graphical user interface (GUI) is developed to acquire, monitor, and display the eight channels' sensor output. GUI plots the online data and offline data as a popup window. The hardware and software of the instrument were tested with standard resistors for calibration and found that in-house developed instrumentation is able to measure with an accuracy of ±0.5% with a resolution of 500 Ω. The instrument has been tested with a semiconductor metal oxide sensor, viz., chromium niobate (CrNbO4).

15.
Nanotechnology ; 31(21): 215604, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32018229

RESUMO

Antibiotic resistance is a highly challenging concern of infectious diseases, and it requires a rational approach to overcome. Through this work, we have synthesized ampicillin-capped gold nanoparticles (Amp-Au NPs) and studied its interaction with bacterial cells. In this process of synthesis, the primary amine group of ampicillin acts as both reducing as well as capping agent. In addition to synthesized gold nanoparticles, the ß-lactam ring remains free to interact with bacteria. This approach not only utilizes the maximum efficiency of nanoparticles and antibiotics towards ampicillin sensitive bacterial cells but also proves to be effective against ampicillin resistance bacteria. Our results illustrate that the optimized system of Amp-Au NPs was formulated by taking 1.25 mM ampicillin and 10-2 of gold ions concentration. UV-vis spectrum of gold nanoparticles and the presence of ampicillin were recorded at around 540 nm and 259 nm, respectively. Microscopic images indicate that particles are nearly spherical and are in size range between 25 and 50 nm. Moreover, formulated Amp-Au NPs show successful accumulation onto the surface of the bacterial cell as a result of which pores were formed into the bacterial membrane. The entry of nanoparticles into bacterial cells was validated through both atomic force microscopy and fluorescent microscopy. The adhesive properties of this coating material and its stability in various pH, i.e. pH 3, pH 7 and pH 10 conditions, could make them a good candidate in the prevention of biofilm formation. Amp-Au NPs show promising antimicrobial activity against ampicillin resistance Escherichia coli bacteria. Furthermore, antimicrobial studies indicate that the efficacy of Amp-Au NPs increased against both ampicillin sensitive and ampicillin resistance bacteria up to sixteen folds and four folds respectively.


Assuntos
Resistência a Ampicilina/efeitos dos fármacos , Ampicilina/farmacologia , Escherichia coli/efeitos dos fármacos , Ouro/química , Ampicilina/síntese química , Ampicilina/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia de Fluorescência , Tamanho da Partícula
16.
Angew Chem Int Ed Engl ; 59(6): 2241-2245, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793166

RESUMO

Owing to a wide range of industrial applications and fundamental importance, delafossite compounds have gathered tremendous interest in research community. In this study, the formation of hexagonal nanoplates of AgInO2 mainly dominated by (00l) facets with no metallic Ag impurity, reported using a facile hydrothermal route at 180 °C using KOH as mineralizer by adopting a factorial design approach. Rietveld analysis of the powder XRD pattern and SAED confirms the rhombohedral system of AgInO2 . FE-SEM image shows a uniform hexagonal plate-like morphology with an average width of about 300 nm and thickness of 70 nm. XPS and EDX analysis confirm potassium ion free AgInO2 . A specific surface area of about 48.5 m2 g-1 is arrived from N2 adsorption studies. Temperature-dependent AC impedance measurements revealed an activation energy of 0.24 eV/f.u. Further, TG-DTA studies found that the compound is stable in air up to 595 °C.

17.
Tech Coloproctol ; 22(2): 75-80, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29159782

RESUMO

BACKGROUND: Cecal volvulus is a rare clinical entity with an average incidence of 2.8-7.1 per million people per year, accounting for 1-2% of all large bowel obstructions. Cecal bascule is the rarest type of cecal volvulus, accounting for 5-20% of all cases. Although several case reports have been published, there is no consensus regarding its diagnosis and treatment. The aim of this study was to review the literature on cecal bascule in order to summarize the etiopathogenesis, clinical features, diagnosis, and treatment options. METHODS: The PubMed, MEDLINE, and Scopus databases were systematically searched by two independent authors. Cecal bascule was defined as anterior displacement of the distended cecum on the ascending colon without any torsion. The etiopathogenesis, clinical features, diagnosis, and treatment options were analyzed. RESULTS: Nineteen previously published papers reporting on 26 patients were included. The mean age of patients from previously reported cases was 55.1 ± 19.2 years, and 54% of all patients were males. Presenting symptoms included abdominal pain in 16 (61%), distension in 22 (84%), and vomiting in eight patients (30%). The mean time to diagnosis was 3.6 ± 2.6 days. The extent of surgery varied from cecopexy to right colectomy. There was no postoperative mortality. Cecal bascule recurred one 1 year after index surgery in one patient. CONCLUSIONS: Cecal bascule is a rare clinical entity, which is mostly encountered in patients with peritoneal adhesions, mobile cecum, bowel dysfunction, and cecal displacement. In patients with recurrent or persistent abdominal pain and distension, cecal bascule should be considered. The majority of these patients require surgical management.


Assuntos
Doenças do Ceco/patologia , Volvo Intestinal/patologia , Doenças do Ceco/cirurgia , Ceco/cirurgia , Colectomia/métodos , Feminino , Humanos , Volvo Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade
18.
Clin Microbiol Infect ; 23(9): 659-666, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28232163

RESUMO

OBJECTIVE: Few industry-independent studies have been conducted to compare the relative costs and benefits of drugs to treat methicillin-resistant Staphylococcus aureus (MRSA) infection. We performed a stochastic cost-effectiveness analysis comparing two treatment strategies-linezolid versus trimethoprim-sulfamethoxazole plus rifampicin-for the treatment of MRSA infection. METHODS: We used cost and effectiveness data from a previously conducted clinical trial, complementing with other data from published literature, to compare the two regimens from a healthcare system perspective. Effectiveness was expressed in terms of quality-adjusted life-years (QALYs). Several sensitivity analyses were performed using Monte Carlo simulation, to measure the effect of potential parameter changes on the base-case model results, including potential differences related to type of infection and drug toxicity. RESULTS: Treatment of MRSA infection with trimethoprim-sulfamethoxazole plus rifampicin and linezolid were found to cost on average €146 and €2536, and lead to a gain of 0.916 and 0.881 QALYs, respectively. Treatment with trimethoprim-sulfamethoxazole plus rifampicin was found to be more cost-effective than linezolid in the base case and remained dominant over linezolid in most alternative scenarios, including different types of MRSA infection and potential disadvantages in terms of toxicity. With a willingness-to-pay threshold of €0, €50 000 and €200 000 per QALY gained, trimethoprim-sulfamethoxazole plus rifampicin was dominant in 100%, 96% and 85% of model iterations. A 95% discount on the current purchasing price of linezolid would be needed when it goes off-patent for it to represent better value for money compared with trimethoprim-sulfamethoxazole plus rifampicin. CONCLUSIONS: Combined treatment of trimethoprim-sulfamethoxazole plus rifampicin is more cost-effective than linezolid in the treatment of MRSA infection.


Assuntos
Antibacterianos , Linezolida , Staphylococcus aureus Resistente à Meticilina , Rifampina , Infecções Estafilocócicas , Combinação Trimetoprima e Sulfametoxazol , Antibacterianos/efeitos adversos , Antibacterianos/economia , Antibacterianos/uso terapêutico , Análise Custo-Benefício , Humanos , Linezolida/efeitos adversos , Linezolida/economia , Linezolida/uso terapêutico , Rifampina/efeitos adversos , Rifampina/economia , Rifampina/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/economia , Infecções Estafilocócicas/epidemiologia , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Combinação Trimetoprima e Sulfametoxazol/economia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
19.
Indian J Psychiatry ; 58(2): 229-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27385862

RESUMO

This article refers to materials of psychiatric interest found in the Manimekalai written by the 2(nd) Century CE Buddhist poet Sathanar. From the early description of a wandering psychotic in the streets of Pukar, the ancient maritime capital of the Cholas it is opined that this description fits that of present-day schizophrenia. A drunkard making fun of a Jain monk and a cross-dressed individual are also found in the same streets. Manimekalai's request to the Chola king to convert the prison to a place of piety with Buddhist monks is mentioned. Lord Buddha's teachings on the compassionate way of life are presented.

20.
J Mol Biol ; 428(14): 2931-42, 2016 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-27117189

RESUMO

The nucleosome remodeling deacetylase (NuRD) complex is a highly conserved regulator of chromatin structure and transcription. Structural studies have shed light on this and other chromatin modifying machines, but much less is known about how they assemble and whether stable and functional sub-modules exist that retain enzymatic activity. Purification of the endogenous Drosophila NuRD complex shows that it consists of a stable core of subunits, while others, in particular the chromatin remodeler CHD4, associate transiently. To dissect the assembly and activity of NuRD, we systematically produced all possible combinations of different components using the MultiBac system, and determined their activity and biophysical properties. We carried out single-molecule imaging of CHD4 in live mouse embryonic stem cells, in the presence and absence of one of core components (MBD3), to show how the core deacetylase and chromatin-remodeling sub-modules associate in vivo. Our experiments suggest a pathway for the assembly of NuRD via preformed and active sub-modules. These retain enzymatic activity and are present in both the nucleus and the cytosol, an outcome with important implications for understanding NuRD function.


Assuntos
Histona Desacetilases/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Nucleossomos/metabolismo , Animais , Núcleo Celular/metabolismo , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Citosol/metabolismo , Drosophila/metabolismo , Camundongos , Subunidades Proteicas/metabolismo , Células-Tronco/metabolismo
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