In vitro metabolism of contraceptive steroids

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Aquaculture extension impacts in Bangladesh: a case study from Kapasia, Gazipur

With many ponds and high demand for fish, Bangladesh has a high potential for aquaculture . Since the 1980s, there have been many aquaculture extension projects. As a result, pond aquaculture production is estimated to have trebled between approximately 1990 and 2000, and is currently estimated to be in order of 750 000 t per year. This gave an ideal opportunity to understand the impacts of aquaculture extension. This study investigated the practices and performance of farmers about six years after specific extension efforts had ended, in order to gain a better understanding of the sustained practices and benefits achieved by fish farmers from extension. It followed up an earlier project in Kapasia Upazila (subdistrict) in Gazipur District north of the capital Dhaka, where the WorldFish Center with funding from the International Fund for Agricultural Development (IFAD) and the Danish International Development Agency (Danida), had researched on farming systems and had introduced adaptive integrated aquaculture practices. Surveys were undertake to compare the aquaculture systems with baseline and project period data.Aquaculture, Fish-culture, Gazipur, Bangladesh,

Aquaculture extention impacts in Bangladesh: a case study from Kapasia, Gazipur

Aquaculture, Bangladesh,

Presenting signs and symptoms of ovarian cancer at a tertiary care hospital

Objective: To identify early warning signs and symptoms of ovarian cancer to create awareness for early diagnosis and management of the disease.Methods: This study was conducted at the department of Gynaecology and Obstetrics, Liaquat National Hospital, Karachi from 2003 to 2007, having 75 patients. The information collected included age, education, and self perceived state of socio-economic class, presenting clinical signs and symptoms, basic and specific laboratory investigations. The disease was staged from I to IV upon surgical staging and the type of cancer was determined by histopathological examination.Results: Mean age of the patients was 51 +/- 12.3 years. Twenty (52%) patients were uneducated, 17 (22.6%) were below and remaining 19 (25.3%) were above higher secondary level. Most of the patients belonged to the middle socioeconomic class. Abdominal pain (57.3%) was the most common presenting symptom followed by abdominal distension (22.6%), urinary complaints (5.3%), vaginal discharge (2.6%) and postmenopausal bleeding (12%). More than half (56%) of the patients had stage III-IV disease. On histology, papillary serous cystic adenocarcinoma was the most common (54%) type followed by mucinious (22%), endometroid (10.6%), yolk sac (2.6%), dysgerminoma (4%), and adult granulose cell tumour (5.3%).Conclusion: There are no specific ovarian carcinoma symptoms either in early or late stages to ensure early diagnosis, but in the age group above 40 years persistent clinical symptoms should always be further investigated

Shift in the role of criminology in criminal law: Reflecting the doctrinal change

Purpose: The study's aim is to assess how criminology's role in criminal law has changed over time. In addition, the author suggested that criminology can be used to test and suggest explanatory theories for criminal law rather than doctrinal shifts. Research methodology: The authors use literature-based observational analysis to assess how criminology's role in criminal law has evolved. Methodical investigation of logical literature uncovered the shift in the role of criminology in criminal law. Results: The authors claim that doctrinal changes have shifted perceptions of criminality, but the study's findings suggest otherwise. Doctrine changes mysteriously and without judicial acknowledgement, revealing shifting facts and suggests that the role of criminology in criminal law may be changing. Limitations: Even after a doctrinal shift, the authors argue, having criminological theories and perspectives helps assign proper rules to criminal law. Contribution: The study's findings support the often-criticized objectivist view of criminology but disagree on the subjectivist view of doctrine shifts. This study suggests that a new field will emerge that transcends both criminology and criminal laws rather than doctrine changes

Use of spread spectrum time domain reflectometry to estimate state of health of power converters

pre-printA new online measurement and analysis method has been presented in this paper to identify the state of health of power converter circuits. Using spread spectrum time domain reflectometry (SSTDR), impedance in the various current paths inside the converter as well as any fault can be identified without interrupting the circuit's normal operation. Multiple sets of test data have been generated while the SSTDR process is applied to each of the components i.e. the power MOSFETs, the dc bus capacitor and the load. These obtained test data are analyzed to show how these test results are consistent with the impedances in various current paths. An impedance matrix was formed for a non-aged converter and a corresponding matrix using SSTDR data was formed as well. The matrices could be formed for any power converter, and the impedance matrix for the non-aged converter could be considered as a "Reference matrix" for comparison purpose. By comparing these two matrices, the variation in path impedances due to aging could be determined. This research aims to identify the measurable quantities to characterize the aging process, their origins of these quantities and propose convenient methods to measure them

Quantifying device degradation in live power converters using SSTDR assisted impedance Matrix

pre-printA noninterfering measurement technique designed around spread spectrum time domain reflectometry (SSTDR) has been proposed in this paper to identify the level of aging associated with power semiconductor switches inside a live converter circuit. Power MOSFETs are one of the most age-sensitive components in power converter circuits, and this paper demonstrates how SSTDR can be used to determine the characteristic degradation of the switching MOSFETs used in various power converters. An SSTDR technique was applied to determine the aging in power MOSFETs, while they remained energized in live circuits. In addition, SSTDR was applied to various test nodes of an H-bridge ac-ac converter, and multiple impedance matrices were created based on the measured reflections. An error minimization technique has been developed to locate and determine the origin and amount of aging in this circuit, and this technique provides key information about the level of aging associated to the components of interest. By conducting component level failure analysis, the overall reliability of an H-bridge ac-ac converter has been derived and incorporated in this paper

Characterization of aging process in power converters using spread spectrum time domain reflectometry

pre-printThis paper aims to find a new technique to predict the state of health of power converters by characterizing the most vulnerable components in the converter without affecting the normal circuit operation. Spread spectrum time domain reflectometry (SSTDR) can detect most of the aged components inside the converter while the converter is operational. Semiconductor switches and electrolytic capacitors are the two most sensitive components in power converter circuits, and this paper demonstrated how SSTDR can be used to determine the degradation of these components. Multiple sets of test data have been generated while the SSTDR process is applied to the power MOSFETs, IGBTs connected in a chopper circuit and to the aluminum electrolytic capacitors connected in an RC circuit. Analysis is done on these obtained test data to show how the SSTDR generated data are consistent with the aging of power MOSFETs, IGBTs and electrolytic capacitors