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1.
ACS Omega ; 8(48): 45369-45383, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38075753

RESUMO

The incorporation of semiconducting materials into the π-conjugate polymer improves the optical, thermal, electrical, and electrochemical properties of optoelectronic devices. In this study, polycarbazole-zinc sulfide (PCZ) composites are synthesized via an in situ polymerization process, and their thin films are produced by spin coating. ZnS enhances the charge transfer qualities of polycarbazoles, which in turn results in better photophysical and electrical characteristics. The PCZ15 thin film has an optical band gap of 2.44 eV, a refractive index of 2.15, and an Urbach energy of 0.44 eV. Relative quantum yield for the PCZ15 was 38.4%, while Förster resonance energy transfer efficiency was 2%. Excellent thermal performance was shown by the PCZ15, which was 37.04% more efficient than the pure polycarbazole with an activation energy of 356 kJ/mol. PCZ15 has an outstanding charge mobility of 54.22 m2/(V s) and a conductivity of 0.298 S/cm. High charge transfer efficiencies were discovered by electrochemical analysis, which had a specific capacitance of 116 Fg-1. These characteristics strongly supported the viability of the PCZ15 thin film as a high-performance polymer-derived composite materials for optoelectronic devices.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 289: 122162, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516514

RESUMO

Luminescent polymeric graphitic composites have the potential to be efficient energy converters for sophisticated displays and light sources. Thermal condensation is used to synthesize g-C3N4-ZnS composites. The XRD, and FTIR analyses confirmed the synthesis of the pure host, filler, and composites. FESEM, and TEM images revealed that the ZnS nanosheets were evenly distributed over the g-C3N4 sheets. As a result of ZnS incorporation, the melting point of g-C3N4 has been raised to 748.5 °C, and the thermal stability of gZ has been increased by 27 %. The optimized gZ15 band gap is determined to be 2.98 eV with a crystallite size of 4.2 nm and a micro stain of 35.42 × 10-3. With a purity of 63.4 %, gZ15 demonstrated a significant rate of recombination in the blue region. gZ15 has a high PLQY of 98 % and a FRET efficiency of 92%. All of the improved properties demonstrated that polymeric g-C3N4-ZnS was the optimum materials for usage in the active or emissive layer of optoelectronic devices.

3.
Ann Card Anaesth ; 23(4): 471-476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33109806

RESUMO

Context: Ventricular septal rupture (VSR) is a dreaded complication following myocardial infarction. Surgical repair of VSR is associated with significant early mortality. Variable outcomes in terms of early mortality and midterm functional status have been reported from different centers. Aims: In our study, we attempt to review the experience of decision making and surgical repair of postinfarction VSR, and to analyze the factors contributing to the early mortality and midterm outcome after repair. Materials and Methods: It is a retrospective study. Data were summarized retrospectively by frequencies and percentages for categorical factors, and means and standard deviations for continuous factors. Multivariate logistic regression, odds ratios, 95% confidence intervals, and P value were calculated for different variables to determine their independent effect on operative mortality. All surviving patients answered the EQ-5D Health Questionnaire. Results: Preoperative renal failure, left ventricular dysfunction (moderate and severe), and Killip class (III and IV) were significantly associated with early mortality after surgery. Small residual ventricular septal defect (VSD) was not found to affect the midterm quality of life. Conclusions: Early surgical repair benefits the patient by preventing early end-organ damage. The renal failure left ventricular dysfunction (moderate and severe) and Killip class (III and IV) adversely affect early outcomes after surgery. Small residual ventricular septal defect (VSD) does not affect the midterm quality of life.


Assuntos
Comunicação Interventricular , Ruptura do Septo Ventricular , Tomada de Decisões , Humanos , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Ruptura do Septo Ventricular/etiologia , Ruptura do Septo Ventricular/cirurgia
4.
Ann Card Anaesth ; 20(1): 104-107, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28074807

RESUMO

The venous anomaly of a persistent left superior vena cava (PLSVC) affects 0.3%-0.5% of the general population. PLSVC with absent right superior vena cava, also termed as "isolated PLSVC," is an extremely rare venous anomaly. Almost half of the patients with isolated PLSVC have cardiac anomalies in the form of atrial septal defect, endocardial cushion defects, or tetralogy of Fallot. Isolated PLSVC is usually innocuous. Its discovery, however, has important clinical implications. It can pose clinical difficulties with central venous access, cardiothoracic surgeries, and pacemaker implantation. When it drains to the left atrium, it may create a right to left shunt. In this case report, we present the incidental finding of isolated PLSVC in a patient who underwent aortic valve replacement. Awareness about this condition and its variations is important to avoid complications.


Assuntos
Achados Incidentais , Veia Cava Superior/anormalidades , Adulto , Ecocardiografia Transesofagiana , Humanos , Masculino , Veia Cava Superior/diagnóstico por imagem
5.
Ann Card Anaesth ; 19(1): 169-72, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26750696

RESUMO

Free wall rupture of the left ventricle (LV) is a rare but life-threatening complication of acute myocardial infaction. Very rarely such rupture may be contained by the adhering pericardium creating a pseudoaneurysm. This condition warrants for an emergency surgery. Left ventricular aneurysm is the discrete thinning of the ventricular wall (<5 mm) with akinetic or dyskinetic wall motion causing an out-pouching of the ventricle. Given the propensity for pseudoaneurysms to rupture leading to cardiac tamponade, shock, and death, compared with a more benign natural history for true aneurysms, accurate diagnosis of these conditions is important. True aneurysm, usually, calls for an elective surgery. Clinically differentiating the two conditions remains a challenge. We report the case of a patient with LV pseudoaneurysm, initially diagnosed as true aneurysm at our institution. We have attempted to review the existing literature and discussed the characteristic findings of each entity.


Assuntos
Falso Aneurisma/diagnóstico , Ventrículos do Coração/patologia , Ventrículos do Coração/cirurgia , Idoso , Falso Aneurisma/cirurgia , Complicações do Diabetes/diagnóstico , Diagnóstico Diferencial , Serviços Médicos de Emergência , Aneurisma Cardíaco/diagnóstico , Ruptura Cardíaca/etiologia , Ruptura Cardíaca/patologia , Humanos , Masculino , Intervenção Coronária Percutânea , Stents
6.
Ann Card Anaesth ; 18(1): 87-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25566717

RESUMO

One of the dreaded mechanical complications of mitral valve replacement (MVR) is rupture of the left ventricle (LV). This report describes the early diagnosis and successful repair of rupture of posterior wall of LV in an elderly patient who underwent MVR. We have discussed the risk factors and perioperative issues implicated in such complication. The anesthesiologist as an intra-operative echocardiographer can aid in identifying the patient at risk. Though important surgical steps are necessary to prevent the complication; nonetheless, the anesthesiologist needs to take key measures in the perioperative period.


Assuntos
Ruptura Cardíaca/etiologia , Ruptura Cardíaca/cirurgia , Implante de Prótese de Valva Cardíaca , Valva Mitral/cirurgia , Complicações Pós-Operatórias/terapia , Calcinose/cirurgia , Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Ecocardiografia , Feminino , Ruptura Cardíaca/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Cardiopatia Reumática/complicações , Cardiopatia Reumática/terapia
9.
Int J Low Extrem Wounds ; 7(4): 198-203, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18815200

RESUMO

Diabetic foot ulcer (DFU) is the leading cause of lower extremity amputation and is generally known to have poor prognosis. Oxidative stress is considered important in the pathogenesis of chronic wounds. Fibrinogen is a recognized marker in peripheral vascular disease; increasing levels predict an increased mortality and risk of amputation. The aim of this study was to evaluate if plasma malondialdehyde (MDA), protein carbonyl (PC) and fibrinogen levels can be used as prognostic markers in patients with DFU. The study design was prospective, nonrandomized, and controlled. A total of 41 DFU grade 1 and 20 DFU grade 2 patients were studied in this case-control study. Diabetic controls without foot ulcers and healthy controls were also studied. Plasma MDA, PC, and fibrinogen levels were significantly higher in patients with DFU compared with those without ulcers (P < .05) and nondiabetic controls (P < .001). These parameters increased in association with DFU grade (P < .01). Increased levels of plasma fibrinogen, MDA, and PC correlated with worsened outcomes. An augmented oxidative stress and plasma fibrinogen level >300.4 mg% (95% confidence interval, 100% sensitivity, 99.2% specificity) was correlated with a high risk of amputation in DFU.


Assuntos
Biomarcadores/sangue , Pé Diabético/diagnóstico , Fibrinogênio/metabolismo , Malondialdeído/sangue , Estresse Oxidativo , Carbonilação Proteica , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Estudos de Casos e Controles , Pé Diabético/sangue , Pé Diabético/patologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade
10.
Indian J Surg ; 70(1): 8-13, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23133008

RESUMO

BACKGROUND: Intussusception is a common cause of acute intestinal obstruction with potentially serious complications. The treatment of choice is an attempt at initial non-operative treatment. AIM: The purpose of the study was to evaluate the efficacy of the technique of hydrostatic reduction of intussusception using saline enema and ultrasound being practiced in our institute; the secondary goal was to identify patient subset in which it is more successful. MATERIAL AND METHODS: The case records of all patients treated for intussusception in our institute from 1st January 2000 to 30th June 2007 were retrospectively analyzed to collect information. All patients with ultrasound diagnosed intussusception that were not having signs of shock or peritonitis were treated with normal saline enema under ultrasound guidance. Failure of three such attempts was an indication for operation. RESULT AND CONCLUSIONS: We found that this technique is easy, safe and extremely effective in treating intussusception in children. The success rate was 81.37% (83 out of 102 cases) and mortality rate was 1.2%. Ileoileocolic type of intussusception failed enema reduction more often (statistically significant; P value = 0.0032) while older patients (statistically significant, P value = 0.001) had higher success rates with the technique. Patients who had colocolic type of intussusception (P value = 0.29) and patients who present early (P value = 0.262) appear to have higher success rates but this was not statistically significant.

11.
Indian J Surg ; 70(4): 161-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23133050

RESUMO

Bedsore is a global problem concerning the bedridden, infirm, debilitated and malnourished patients in hospitals and community setups. The cost of treatment is enormous involving billions of dollars to nations and individuals. Mortality increases two to six times if bedsores are present. There is little research done despite its commonness to understand how they occur or why they occur; etiology is not much understood. The two theories called 'top to bottom' and 'bottom to top' contradict each other. It is thought that 'pressure', shear-stress' and 'ischemia' may be causing it in some yet to be understood way.There is little awareness on how to prevent them or how to treat them if they do occur. Seldom applied, various scales exist and should be used to identify patients at high risk. Braden scale is the most tested and widely accepted scale. The various available dressings and pressure relief devices are mostly inadequately studied; which is superior is a question that begs an answer. This article aims to underline the importance of bedsores by reviewing our current and past knowledge with emphasis on practical implications thereof.

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