Enhancement of Mixing Performance of Two-Layer Crossing Micromixer through Surrogate-Based Optimization.

Optimum configuration of a micromixer with two-layer crossing microstructure was performed using mixing analysis, surrogate modeling, along with an optimization algorithm. Mixing performance was used to determine the optimum designs at Reynolds number 40. A surrogate modeling method based on a radial basis neural network (RBNN) was used to approximate the value of the objective function. The optimization study was carried out with three design variables; viz., the ratio of the main channel thickness to the pitch length (H/PI), the ratio of the thickness of the diagonal channel to the pitch length (W/PI), and the ratio of the depth of the channel to the pitch length (d/PI). Through a primary parametric study, the design space was constrained. The design points surrounded by the design constraints were chosen using a well-known technique called Latin hypercube sampling (LHS). The optimal design confirmed a 32.0% enhancement of the mixing index as compared to the reference design.

Etiological pattern of demented patients attending in a tertiary hospital.

This is a cross sectional study where 125 demented patients were enrolled who attended in neurology department of Bangabandhu Sheikh Mujib Medical University (BSMMU) Hospital. The purpose of the study was to find out the etiology of dementia. Dementia was diagnosed by the criteria indicated by Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV and confirmed by Mini Mental State Examination (MMSE) score. Diagnosis of specific type of dementia was made on the basis of established criteria. The most common etiological factor was post stroke dementia (PSDE) (36%) followed by Alzheimer's disease (AD) (14.4%), multi infarct dementia (MID) (8%), Mixed AD and PSDE (6.4%), vitamin B12 deficiency (4.8%) etc. Vascular dementia is the most common etiological factor. Next to this is the Alzheimer disease. This study will provide baseline information regarding the types of dementia occurring in Bangladeshi population and will be the basis of planning health program and data for future research.

Proteinuria is an independent risk factor for ischemic stroke among diabetic patients.

This study was done to assess the relationship between proteinuria and ischemic stroke in subjects with diabetes mellitus, and to determine whether proteinuria is an independent risk factor for stroke. This comparative study was conducted in Mymensingh Medical College Hospital from January 2009 to June 2010. It was done to establish the relationship between proteinuria (Microalbuminuria) and ischemic stroke among diabetic patients. Other risk factors were also assessed. Patients were divided in Group A - diabetic patients with ischemic stroke (n=50) and Group B diabetic patients without stroke (n=50). Mean age of the Group A & B were 60.16±8.33 and 57.19±7.73 years (p=0.068). Mean Blood sugar (2 hours after Break Fast) was 14.68±4.32mmol/L in Group A and 14.75±4.02mmol/L in Group B (p>0.05). Albumin Creatinine ratio was abnormal in 84.0% in Group A and 22.0% in Group A (p=0.001) [Odds ratio (95%CI) = 18.61 (6.78-51.09)]. Logistic regression analysis has also shown that microalbuminuria (ACR) is an independent risk factor for ischemic stroke (p=0.001), [Odds ratio (95%CI) = 19.811(5.915-66.348)]. In diabetic patients increased urinary protein is a risk factor for stroke. Estimation of urinary protein (Microalbuminuria) may be used as a predictor for ischemic stroke in patients with diabetes.

An unusual growth pattern of a mucin-producing intrahepatic cholangiocellular carcinoma involving the hepatic hilus.

The case of a mucin-producing intrahepatic cholangiocellular carcinoma in a 73 year-old-man is presented. A tumor originating in the right posterior inferior segment of the liver was found to be invading the right posterior and anterior bile ducts, and the hepatic hilus. Extensive superficial spread was observed in the entire posterior segmental bile duct extending to the hepatic hilus. Mucin produced and excreted by the tumor was retained in the common hepatic and common bile duct. The diagnosis in this case was suggested by percutaneous transhepatic aspiration of mucinous bile, and was confirmed by utilizing the techniques of ultrasonography, percutaneous transhepatic cholangiography, computed tomography and angiography. Curative surgery, which included right hepatic lobectomy with total caudate lobectomy and bile duct resection, was performed. Biliary continuity was maintained by left hepaticojejunostomy using a Roux-en-Y jejunal loop. The histological diagnosis was mucin-producing papillary adenocarcinoma originating in the right posterior inferior segment of the liver. Postoperative recovery was very good and the patient has now been enjoying a good active social life for the last 20 months with no signs of tumor recurrence. This case report discusses the unusual growth pattern of a mucin-producing intrahepatic cholangiocellular carcinoma involving the hepatic hilus, and suggests rational surgical treatment.

A case of early asymptomatic carcinoma of the hepatic hilus.

We describe a 54-year-old asymptomatic male with carcinoma of the hepatic hilus. Elevated serum transaminases were detected during the annual medical examination. The diagnosis was confirmed by ultrasonography (US), computed tomography (CT), percutaneous transhepatic cholangiography (PTC) and endoscopic retrograde cholangiopancreatography (ERCP). Curative surgery, which included right hepatic lobectomy with total caudate lobectomy, was performed. The resected specimen revealed a localized tumor in the right anterosuperior dorsal intrahepatic bile duct branch. The histological diagnosis was moderately differentiated tubular adenocarcinoma. The patient's postoperative recovery was smooth and he has remained in good health for 15 months after surgery without any signs of recurrence. This case report discusses the early diagnosis and rational surgical treatment for carcinoma of the hepatic hilus.

Resection of intrahepatic bile duct carcinoma with hilar bile duct and portal vein invasion--a case report.

A case of resected intrahepatic bile duct cancer with hilar bile duct and portal vein invasion is presented. Percutaneous transhepatic biliary drainage was performed to alleviate jaundice and evaluate the biliary system. Intraductal tumor extension was determined, and an accurate histological diagnosis was made in biopsy material obtained under percutaneous transhepatic cholangioscopy. Preoperative surgical planning was carried out on the basis of an evaluation of the findings of ultrasonography, computed tomography, arteriography, portography and percutaneous transhepatic cholangioscopy. Curative surgery, which included right hepatic lobectomy with total caudate lobectomy and combined resection and reconstruction of the portal vein, was performed. Bilioenteric continuity was re-established by a Roux-en-Y jejunal loop. The histological diagnosis was moderately differentiated tubular adenocarcinoma originated in the right posterior branch of the intrahepatic bile duct. Postoperative recovery was very good, and the patient has now been enjoying a good active social life for the past three years with no signs of tumor recurrence. This case report discusses the accurate diagnosis and rational surgical treatment for intrahepatic bile duct carcinoma with hilar invasion.