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1.
Mymensingh Med J ; 33(2): 426-432, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38557521

RESUMO

Functional dyspepsia (FD) is a common gastrointestinal problem in the world. The Rome III consensus subdivided functional dyspepsia into two groups: meal-related postprandial distress syndrome (PDS) and meal-unrelated epigastric pain syndrome (EPS). Limited data are available regarding FD in Bangladesh. The aim of this study was to investigate the demographic and clinical characteristics of FD and its sub-types. This cross-sectional study was conducted in which we recruited patients who attended the outpatient department of Gastroenterology of Bangabandhu Sheikh Mujib Medical University, Bangladesh from March 2017 to February 2018. Patients fulfilling Rome III FD criteria and a negative upper GIT endoscopy were included for this study. The patients were then subdivided into 'pure' PDS (i.e. meeting criteria for PDS without EPS symptoms), 'pure' EPS (i.e., meeting criteria for EPS without PDS symptoms), and overlapping PDS-EPS (i.e., symptoms of both PDS and EPS) groups. Total of 368 FD patients (56.0% females, mean age 32.8±8.6 years, BMI: 22.0±2.7), were included in this study. Out of them, 112(30.4%) patients (57.2% females, mean age 33.9±9.3 years, BMI: 22.0±2.7) fulfilled criteria of pure EPS and 64(17.4%) patients (68.8% females, mean age 33.2±7.8 years, BMI: 22.1±2.4) fulfilled criteria of pure PDS. However, the majority of patients [192(52.2%), 52.1% females, mean age 32.0±8.4 years, BMI: 21.9±2.8] had symptoms of overlapping EPS-PDS. More than 40% of patients in our study presented with 3 or more of the four key symptoms of FD. A longer duration of presenting symptoms was seen among patients with overlapping EPS-PDS in comparison to pure EPS and pure PDS (p<0.001). A significant overlap of symptoms of both EPS and PDS was noticed among patients with FD. The value of dividing functional dyspepsia into the subgroups of PDS and EPS is thus questionable. Further research and modification of the diagnostic criteria for FD subtypes are necessary.


Assuntos
Dispepsia , Adulto , Feminino , Humanos , Adulto Jovem , Masculino , Dispepsia/diagnóstico , Dispepsia/epidemiologia , Dor Abdominal/epidemiologia , Dor Abdominal/etiologia , Bangladesh/epidemiologia , Centros de Atenção Terciária , Estudos Transversais , Demografia
2.
Mymensingh Med J ; 32(1): 111-117, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36594310

RESUMO

Data on stool form and defecation frequency which are a prerequisite for defining normal bowel habit are lacking in Bangladesh. This observational cross sectional study was designed to find out defecation frequency and stool form among general population in Bangladesh. This study was performed in the Department of Gastroenterology, Shaheed Suhrawardy Medical College Hospital, Dhaka, Bangladesh from July 2017 to June 2018. Apparently healthy 1090 respondents were evaluated for predominant stool form (Bristol chart) and frequency. Data on demographic and life-style were collected. The study population consisted of 1090 respondents, among them, 65.13% male and 34.87% female and mean age of them was 40.20±12.39 years. Most of the people 874(80.2%) passed stool between 12-14 times per week followed by 111(10.2%) less than 3 stools per week, 95(8.7%) passed more than 14 stools per week and 10(0.9%) between 3-12 stools per week, p<0.001. Most people passed predominantly Bristol type IV stool- 610(56.0%); followed by type III- 274(25.1%). Other stool forms were: type I- 52(4.8%), type II- 59(5.4%), type V- 31(2.8%), type VI- 33(3.0%), type VII- 31(2.8%), p<0.001. In regard to the physical activity, most of the respondents (70.0%) are physically active whereas about 13.0% are sedentary and about 17.0% are physically intermediate between the two, p<0.001. In the case of dietary habit, most of the participants are non-vegetarian (82.5%) and the remaining are vegetarian (11.1%) and occasional non vegetarian (6.4%), p<0.001. Median stool frequency in the studied population was 14 per week and predominant form was Bristol type IV. Older age was associated with lesser stool frequency, particularly among female subjects.


Assuntos
Defecação , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Bangladesh , Fezes , Estudos Transversais
3.
Mymensingh Med J ; 31(4): 1202-1205, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36189573

RESUMO

Cough, hemoptysis, chest pain, and weight loss are classic symptoms of bronchial carcinoma. Small cell lung cancer presents late with obviously abnormal chest radiographs and with bulky, usually mediastinal lymph node involvement. Dysphagia rarely occurs in patients with bronchial carcinoma. There are many causes of dysphagia in bronchial carcinoma such as mediastinal lymphadenopathy, direct tumor invasion of the mediastinum, radiotherapy, secondary achalasia. This report presents a case of progressive dysphagia to solid foods and weight loss of a 28-year-old male, non-smoker due to subcarinal lymph node enlargement from metastatic bronchial adenocarcinoma.


Assuntos
Adenocarcinoma , Carcinoma Broncogênico , Transtornos de Deglutição , Neoplasias Pulmonares , Linfadenopatia , Adenocarcinoma/patologia , Adulto , Carcinoma Broncogênico/patologia , Transtornos de Deglutição/etiologia , Humanos , Neoplasias Pulmonares/patologia , Linfonodos/diagnóstico por imagem , Metástase Linfática/patologia , Masculino , Mediastino , Estadiamento de Neoplasias , Redução de Peso
4.
Mymensingh Med J ; 30(2): 559-561, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33830143

RESUMO

Hepatitis A virus (HAV) is the most common cause of acute viral hepatitis in the world. Infection with hepatitis A virus can cause severe or even fatal illness in patients with chronic liver disease. Here we present a case which seems to be an isolated acute viral hepatitis A infection at the beginning but later found to be coexisted with Wilson's disease. A 14-year-old girl presented in the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh on 11th April 2019 with progressive jaundice with prodrome, dark urine, itching, hepatomegaly and thyromegaly. She was found positive for serum IgM HAV antibody. Her jaundice was increasing along with prolonged prothrombin time and low albumin. She had coexisting Wilson's disease evidenced by increased 24 hours urinary copper (138µgm/day). She was treated with D-Penicillamine and Zinc acetate. Hepatitis A can be considered as a factor for acute decompensation in undiagnosed patients with Wilson's disease. So it is very crucial to investigate Wilson's disease in appropriate clinical setting of prolonged jaundice and liver dysfunction.


Assuntos
Vírus da Hepatite A , Hepatite A , Degeneração Hepatolenticular , Icterícia , Adolescente , Bangladesh , Cobre , Feminino , Hepatite A/complicações , Hepatite A/diagnóstico , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/diagnóstico , Degeneração Hepatolenticular/tratamento farmacológico , Humanos , Icterícia/diagnóstico , Icterícia/etiologia , Penicilamina
5.
Mymensingh Med J ; 28(1): 150-156, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30755564

RESUMO

Several mechanisms have been proposed to explain the symptoms of functional dyspepsia but actual pathogenesis is still poorly understood. Recent studies support duodenal abnormality to be the most important causal link to explain symptoms and to understand abnormal pathophysiology of functional dyspepsia. The aim of this prospective observational study is to compare eosinophil count in duodenal mucosa between patients with functional dyspepsia and control subjects without dyspepsia and was done at the department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from December 2015 to December 2016. Total 42 patients of functional dyspepsia based on Bangla validated version of ROME III criteria and 42 controls who were referred for upper gastrointestinal endoscopy for reasons other than dyspepsia were included. Biopsy specimens were collected from the second part (D2) of the duodenum of all participants. Eosinophil count was quantitatively evaluated by hematoxylin and eosin staining and expressed in numbers per 5 HPF. Significantly increased duodenal eosinophil count was found in functional dyspepsia group than non dyspeptic patients (22.78±08.78 vs. 14.90±10.70, p=0.001). Higher duodenal eosinophil count was found in patients with postprandial distress syndrome. Increased duodenal eosinophil count was found in patient of functional dyspepsia. It requires further large scale multicenter studies to establish duodenal eosinophilia as a biomarker of functional dyspepsia.


Assuntos
Duodeno/metabolismo , Dispepsia/metabolismo , Eosinófilos/metabolismo , Adulto , Bangladesh , Estudos de Casos e Controles , Duodeno/patologia , Dispepsia/patologia , Eosinófilos/patologia , Humanos , Estudos Prospectivos
6.
Mymensingh Med J ; 26(1): 141-144, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28260768

RESUMO

The incidence of peptic ulcer has steadily declined through out the world. This decreasing trend is also noticeable in this subcontinent. The point prevalence of peptic ulcer (PUD) in Bangladesh was around 15% in eighties. The aim of this study was to see the present prevalence of peptic ulcer at endoscopy and to identify changing trends in the occurrence of peptic ulcer in Bangladesh. This retrospective analysis of the endoscopic records of multiple tertiary referral centres of Dhaka city were done from January 2012 to July 2013. A total of 5608 subjects were the study samples. We included those patients having peptic ulcer in the form of duodenal ulcer, benign gastric ulcer including pre-pyloric ulcer and gastric outlet obstruction due to peptic ulcer. Duodenal ulcer and benign gastric ulcer were found in 415(7.4%) and 184(3.28%) patients respectively and gastric outlet obstruction due to peptic ulcer was found in 23(0.40%) patients.


Assuntos
Obstrução da Saída Gástrica , Úlcera Péptica , Bangladesh/epidemiologia , Obstrução da Saída Gástrica/epidemiologia , Humanos , Incidência , Úlcera Péptica/epidemiologia , Estudos Retrospectivos
7.
Mymensingh Med J ; 25(4): 726-729, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27941738

RESUMO

This cross-sectional observational study was conducted in the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Sir Salimullah Medical College and Mitford Hospital, Holy family Red Crescent Medical College and Hospital and Popular Diagnostic Centre, Shantinagar branch, Dhaka, Bangladesh from January 2012 to July 2013. Study subjects were included in the study irrespective of age and sex having different upper GI tract. Complaints like dysphagia, heart burn, abdominal pain/dyspepsia, nausea, vomiting, haematemesis and/or malena, anorexia, unexplained anemia, weight loss etc. All the findings of oesophagus, stomach and duodenal lesions were observed and data were recorded. The results were considered positive based on the macroscopic appearance using standard diagnostic criteria. During the study period endoscopy was performed in 5608 subjects. Among which 2968(52.92%) were male and 2640(47.07%) were female. The patients age range from 7 years to 108 years. The majority of the patients were from 40-50 years. Normal findings were observed among 3321(59.21%) cases. Gastroduodenal erosions were present among 684(12.19%) cases, Oesophageal varices in 444(7.91%) cases, duodenal ulcer diseases in 415(7.40%) cases and gastric ulcer in 184(3.28%) cases. Ca stomach was found among 165(2.94%) cases. A number of diseases were identified through this procedure. Current study observed a large proportion of patients (40.79%) had positive upper GI endoscopy.


Assuntos
Endoscopia do Sistema Digestório , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bangladesh , Criança , Estudos Transversais , Varizes Esofágicas e Gástricas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Mymensingh Med J ; 24(3): 550-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26329954

RESUMO

Though pulmonary tuberculosis is the common presentation of Mycobacterium tuberculosis infection, extra-pulmonary tuberculosis is also a growing problem worldwide. Tuberculous pleural effusion is the second frequent form of extra-pulmonary presentation after tuberculous lymphadenitis and if untreated up to 65% of patients with tubercular pleural effusions will eventually develop active TB. Traditional diagnostic methods are very useful for the diagnosis of pulmonary TB but have a low yield when applied to pleural fluid. So,the aim of this study was to evaluate the diagnostic value of ADA level in plural fluid and other conventional methods for diagnosis of tubercular plural effusion. This was a cross sectional study. This study was carried out in 64 Patients suffering from plural effusion and were consecutively selected and divided into two groups: tuberculous (n=40) and non tuberculous (n=24), depending upon etiology. Details clinical history, physical examination, routine and other relevant investigations including ADA estimation was measured. The mean value of ADA in the tuberculous group was 64.11 ± 19.50 U/L which was significantly higher (p<0.05). Cut off value of ADA was ≥ 40 U/L with 97% sensitivity and 93%specificity. In this study, sensitivity, specificity, PPV and NPV of ADA level in pleural effusion were more significant than other conventional parameters.


Assuntos
Adenosina Desaminase/análise , Biomarcadores/análise , Derrame Pleural/enzimologia , Tuberculose Pulmonar/diagnóstico , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Tuberculose Pulmonar/patologia
9.
Mymensingh Med J ; 24(3): 542-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26329953

RESUMO

Several serum tumour markers have been described for gastric cancer. Preoperative level of tumor marker helps to predict the diagnosis of gastric carcinoma. CA72-4 as a serum tumour marker for gastric cancer is evaluated, and compared its utility in this regard with that of carcinoembryonic antigen (CEA). Analysis of gastric carcinoma by serum levels of CEA and CA72-4 and their correlation with histopathology help the clinician to develop his management strategies for gastric carcinoma. A prospective observational study was carried out in the Department of Clinical Pathology, Bangabandhu Sheikh Mujib Medical University (BSMMU) in collaboration with Department of Surgery BSMMU, DMCH, Delta Hospital Limited, Dhaka, during the period of October 2010 to September 2011. Serum CA72-4 and CEA were analyzed in 71 endoscopically suspected patients for gastric carcinoma. Among them 58 cases were diagnosed as malignant gastric disease and 13 cases were nonmalignant gastric disease. Sensitivity of CA 72-4 and CEA were 48.3% and 31% respectively and specificity were 92.3% and 76.9% respectively. In poorly differentiated carcinoma, positivity for CA72-4 and CEA were 55.6% and 36.1% respectively. Because of the high positivity of CA72-4 in poorly differentiated carcinoma, CA72-4 is reliable tumour marker in advanced cases. As the sensitivity of CA72-4 was more than that of CEA in diagnosis of gastric cancer, CA72-4 can be used in conjunction with other diagnostic tests like endoscopy that would be more helpful for the patients.


Assuntos
Antígenos Glicosídicos Associados a Tumores/sangue , Biomarcadores Tumorais/sangue , Antígeno CA-19-9/sangue , Neoplasias Gástricas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Bangladesh , Antígeno Carcinoembrionário , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Neoplasias Gástricas/sangue , Neoplasias Gástricas/patologia , Adulto Jovem
10.
Mymensingh Med J ; 24(3): 558-63, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26329955

RESUMO

CTGF/CCN2 plays an important role in the formation and development of hepatic fibrosis. This study determined the correlation between serum CTGF/CCN2 and stages of hepatic fibrosis and explored the clinical value of serum CTGF/CCN2 in the assessment of hepatic fibrosis in chronic hepatitis B. This cross sectional study was done in department of Clinical Pathology, Bangabandhu Sheikh Mujib Medical University, Dhaka from March 2012 to February 2013. Serum CTGF was measured by using of a sandwich immunoassay technique. Forty (40) chronic hepatitis B patients were included in this study. The sensitivity of CTGF/CCN2 was 71.6%, specificity 67.5%. Spearman's rank correlation coefficient was 0.652 between serum CTGF/CCN2 and stages of hepatic fibrosis (p<0.001). The area under receiver-operating curve (ROC) was 0.750 for identification of hepatic fibrosis. This present data revealed that serum CTGF/CCN2 in chronic hepatitis B were strongly associated with stages of hepatic fibrosis. CTGF/CCN2 may useful diagnostic tool for assessing the hepatic fibrosis in chronic hepatitis B.


Assuntos
Biomarcadores/sangue , Fator de Crescimento do Tecido Conjuntivo/sangue , Hepatite B Crônica/diagnóstico , Cirrose Hepática/diagnóstico , Adulto , Bangladesh , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite B Crônica/sangue , Humanos , Cirrose Hepática/sangue , Masculino , Valor Preditivo dos Testes
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 146: 286-91, 2015 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-25819317

RESUMO

In this study, we have reported a fast and eco-benign procedure to synthesis silver nanoparticle at room temperature using potato (Solanum tuberosum) infusion along with the study of its photocatalytic activity on methyl orange dye. After addition of potato infusion to silver nitrate solution, the color of the mixture changed indicating formation of silver nanoparticles. Time dependent UV-Vis spectra were obtained to study the rate of nanoparticle formation with time. Purity and crystallinity of the biogenic silver nanoparticles were examined by X-ray diffraction (XRD). Average size and morphology of the nanoparticles were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Fourier transform infra-red spectroscopy (FTIR) was employed to detect functional bio-molecules responsible that contribute to the reduction and capping of biosynthesized Ag nanoparticles. Further, these synthesized nanoparticles were used to investigate their ability to degrade methyl orange dye under sunlight irradiation and the results showed effective photocatalytic property of these biogenic silver nanoparticles.


Assuntos
Compostos Azo/química , Nanopartículas Metálicas/química , Processos Fotoquímicos , Prata/química , Solanum tuberosum/química , Catálise , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
12.
Mymensingh Med J ; 22(4): 773-80, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24292311

RESUMO

This cross-sectional observational study was conducted in the department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. Plasma concentration of omeprazole was assayed in the quality control laboratory of Novartis (Bangladesh) Limited, Tongi, Gazipur, Bangladesh. The study was conducted from January 2006 to April 2007 and was designed to find out the bioavailability of omeprazole in capsule form in healthy Bangladeshi population and to compare this with that of the other population in the world. Twelve healthy volunteers were included in this study. The subjects were divided into two groups; six of them were randomly selected in each. One group received 40mg omeprazole intact capsule of one trade and other group received 40mg omeprazole intact capsule of another trade once daily for consecutive 8 days at 8.00 hours on each day. On the first and eight days of dosing, 10ml of blood sample was collected from each subject at 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 and 6.0 hours after dosing. Blood samples were centrifuged at 2500rpm for 15 minutes and plasma was stored at 20°C. Omeprazole concentration in plasma was determined using a reverse phase high performance liquid chromatography (HPLC). From the concentration, the area under the curve (AUC) of omeprazole was determined for each subject by the trapezoidal rule. From the result it was observed that the plasma concentration of omeprazole was increased up to 6 hours in both trade-A and trade-B in day 1 and 8. Thus the AUC of omeprazole was also increased. But most of the studies in western population showed that the maximum plasma concentration was within 0.5 to 2.0hours indicating a difference from that of western studies. In this study all the subjects exhibited increased plasma concentration and AUC which may be due to genetic variation of omeprazole metabolism as an Asian which may be due to slow or "Poor metabolizers" (PMs), of the study population, who are deficient in CYP2C19. It is revealed that the plasma concentration and AUCs of both the products after single and repeated doses of omeprazole capsule were higher in comparison to other studies in western population.


Assuntos
Omeprazol/farmacocinética , Inibidores da Bomba de Prótons/farmacocinética , Adulto , Área Sob a Curva , Disponibilidade Biológica , Estudos Transversais , Humanos , Masculino
13.
J Phys Condens Matter ; 24(23): 235501, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22551761

RESUMO

An ab initio calculation has been carried out to investigate the biaxial strain ( - 10.71% < ε < 9.13%) effect on elastic, electronic and optical properties of CuAlO(2). All the elastic constants (c(11), c(12), c(13), c(33)) except c(44) decrease (increase) during tensile (compressive) strain. The band gap is found to decrease in the presence of tensile as well as compressive strain. The relative decrease of the band gap is asymmetric with respect to the sign of the strain. Significant differences between the parallel and perpendicular components of the dielectric constant and the optical properties have been observed due to anisotropic crystal structure. It is further noticed that these properties are easily tunable by strain. Importantly, the collective oscillation of the valence electrons has been identified for light polarized perpendicular to the c-axis. From calculations, it is clear that the tensile strain can enhance the hole mobility as well as the transparency of CuAlO(2).

14.
Indian J Exp Biol ; 49(7): 534-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21800504

RESUMO

Makaradhwaja, an alchemical Ayurvedic mercury preparation is used as stimulant and vitalizer. Towards veterinary practices, the acceptability, tolerability and toxicity studies were undertaken in geriatric pet dogs aged more than 10 years irrespective of breed and sex for future use. Makaradhwaja (2.5 mg/kg) was used with honey once daily for 30 days. Before and after treatment, blood was collected for hematological studies as well as liver, kidney function and anti-oxidant activity. In control group, honey itself showed no appreciable change whereas, Makaradhwaja lowered neutrophil and total leucocyte count. Serum cholesterol, urea, glucose, alanine amino transferase, aspartate amino transferase, sodium, phosphorus and calcium were decreased. Haemoglobin and serum creatinine were significantly increased. There was appreciable physical, behavioral and body weight change including quality of life. The dose was used in replication of human dose (125 mg/50 kg). Anti-oxidant study showed significant increase of lipid per oxidation in experimental group while the values of ABTS radical cation decolorisation assay although decreased but did not show any significant changes. Decrease of serum urea and increase of serum creatinine could not be explained on single dose response. Different dose study could only explain the optimum dose to be required in canine practices.


Assuntos
Envelhecimento/efeitos dos fármacos , Ayurveda , Compostos de Mercúrio/farmacologia , Envelhecimento/sangue , Envelhecimento/psicologia , Animais , Antioxidantes/metabolismo , Comportamento Animal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cães , Mel , Testes de Função Renal , Testes de Função Hepática , Compostos de Mercúrio/administração & dosagem , Compostos de Mercúrio/toxicidade
15.
J Phys Condens Matter ; 21(11): 115804, 2009 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21693930

RESUMO

Stoichiometric NiO, a Mott-Hubbard insulator at room temperature, shows p-type electrical conduction due to the introduction of Ni(2+) vacancies (V(Ni)('')) and self-doping of Ni(3+) ions in the presence of excess oxygen. The electrical conductivity of this important material is low and not sufficient for active device fabrication. Al doped NiO thin films were synthesized by radio frequency (RF) magnetron sputtering on glass substrates at a substrate temperature of 250 °C in an oxygen + argon atmosphere in order to enhance the p-type electrical conductivity. X-ray diffraction studies confirmed the correct phase formation and also oriented growth of NiO thin films. Al doping was confirmed by x-ray photoelectron spectroscopic studies. The structural, electrical and optical properties of the films were investigated as a function of Al doping (0-4 wt%) in the target. The room temperature electrical conductivity increased from 0.01-0.32 S cm (-1) for 0-4% Al doping. With increasing Al doping, above the Mott critical carrier density, energy band gap shrinkage was observed. This was explained by the shift of the band edges due to the existence of exchange and correlation energies amongst the electron-electron and hole-hole systems and also by the interaction between the impurity quasi-particle system.

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