Strukturna, elastična, elektronska i rešetkina svojstva legura GaPxAsySb1−x−y S rešetkama priležnim dvjema podlogama

Information on the energy band gaps, the lattice parameter and the lattice matching to available substrates is a prerequisite for many practical applications. A pseudopotential plane-wave method, as implemented in the ABINIT code, is used to the GaPxAsySb1−x−y quaternary alloy lattice matched to GaAs and InP substrates to predict their energy band gaps, elastic constants and lattice dynamic properties. The ranges of compositions for which the alloy is lattice-matched to GaAs and InP are determined. A very good agreement is obtained between the calculated values and the available experimental data of GaAs and GaAs0.5Sb0.5 parents. The compositional dependence of direct and indirect band gaps has been investigated. Note that a phase transition occurred at As composition of 0.018 and 0.576 for GaPxAsySb1−x−y within InP and GaAs substrates. The static and high-frequency dielectric constants and refractive index are indeed inversely proportional (proportional) to the fundamental band gap for GaPxAsySb1−x−y within InP (GaAs) substrates. We study the variation of elastic constants, the optical phonon frequencies (ωTO and ωLO) and the Born effective charge Z* with As concentration.Podaci o energijskim procijepima, parametrima rešetke i prileživanju na dostupne podloge je preduvjet mnogin primjenama. Rabimo metodu ravnih valova s pseudopotencijalom, primijenjenu u programu ABINIT, da bismo predvidjeli procijepe energijskih vrpci, elastične konstante i dinamička svojstva rešetaka legure GaPxAsySb1−x−y s četiri sastavnice, priležne na GaAs i InP podloge. Odredili smo područja sastava za koja rešetke priliježu na GaAs i InP. Postigli smo vrlo dobar sklad izračunatih vrijednosti s eksperimentalnim podacima za polazne legure GaAs i GaAs0.5Sb0.5. Istražili smo ovisnost izravnih i neizravnih procijepa vrpci o sastavu. Opaža se pojava faznog prijelaza za sadržaj As od 0.018 i 0.576 u GaPxAsySb1−x−y na InP i GaAs podlogama. Statičke i visokofrekventne dielektrične konstante te indeks loma su obrnuto razmjerni (razmjerni) širini osnovnog procijepa vrpci u GaPxAsySb1−x−y na InP and GaAs podlogama. Proučavamo promjene elastičnih konstanti, optičkih fononskih frekvencija (ωTO i ωLO) te Bornovog efektivnog naboja Z ∗ u ovisnosti o sadržaju As

Socio-economic and Demographic factors associated with injecting drug use among drug users in Karachi, Pakistan

Objective: To identify the socio-economic and demographic factors associated with injecting drug users (IDUs) in Karachi. Methods: We recruited 242 IDUs (taking drugs through sub-dermal routes) and 231 non-IDUs (taking drugs other than sub-dermal routes) from February through June 1996. IDUs were interviewed regarding sociodemographic factors, economic condition, and social network (marital status, living with spouse). In addition, information regarding location of drug users within the city (districts of Karachi) and current history of sexually transmitted diseases (STDs) were gathered. Moreover, blood samples were also obtained for HIV testing .Results: Multivariate analysis showed that the income generation via illegal modes [AOR 1.6, 95% CI 1.0-2.6], non-sharing of income with family [AOR 1.7, 95% CI 1.1-2.7] and presence of suicidal thoughts [AOR 2.0, 95% CI 1.1-3.8] were associated with the use of drugs through injections. Further, drug users from districts West, East and Central were more likely to use drug through injection as compared to drug users from district South. The history of genital herpes was also found to be associated with injecting drug use. One IDU was found seropositive for HIV. Conclusion: The high-risk behaviors, such as illegal modes of earning and presence of suicidal thoughts, among IDUs suggest that the group needs rehabilitation programme. Moreover, non-sharing of income suggest that IDUs are isolated from social network, therefore primary prevention activities with focus on improving socioeconomic conditions and social networking can reduce drug use through injections. Focused interventions on target districts would be helpful in reducing IDU (JPMA 53:511;2003)

Formative assessment of the communication skills related to drug delivery systems on standardized patients through group objective structured clinical encounters in second year medical students

Background: Choosing an appropriate Drug Delivery System (DDS) influences the acceptability, adherence and better outcome of the therapy in the patients. The present study was planned to evaluate the second year MBBS students on standardized patients (SP) using Group Objective Structured Clinical Encounters (GOSCE) after content delivery by traditional power point class versus experiential teaching methodology.Methods: DDS practical class was held in two larger groups after adding two odd sub-groups (1+3) as ‘A’ (64 students) and even sub-groups (2+4) as ‘B’ (66 students). The formative GOSCE evaluation was done 2 weeks after the classes by the trained physician examiners as per the Medical Council of Canada pre-determined scoring instruments.Results: The average magnitude of change in GOSCE scoring is extremely statistical significant on t-test (P< 0.0001) in favour of experiential teaching methodology for all the skills. The statistical significant percentage of students were able to extract the treatment history in respect of eliciting problem, reasons for non-compliance, methods of intake, explain the technique and showed the courteous professional behaviours.Conclusions: The clinical cases as SP in pharmacology teaching for developing competency based communication skills and GOSCE are the appropriate methodology for evaluation of large student group for experiential DDS training

Dynamics of Post-Injection Fuel Flow in Mini-Sac Diesel Injectors Part 1: Admission of 1 External Gases and Implications for Deposit Formation

Samples of unadditized, middle distillate diesel fuel were injected through real-size optically accessible mini-sac diesel injectors into ambient air at common rail pressures of 250 bar and 350 bar respectively. High-resolution images of white light scattered from the internal mini-sac and nozzle flow were captured on a high-speed monochrome video camera. Following the end of each injection, the momentum-driven evacuation of fuel liquid from the mini-sac and nozzle holes resulted in the formation of a vapour cloud and bubbles in the mini-sac, and vapour capsules in the nozzle holes. This permitted external gas to gain entrance to the nozzle holes. The diesel fuel in the mini-sac was observed to rotate with large initial vorticity, which decayed until the fuel became stationary. The diesel fuel remaining in the nozzle holes was observed to move inwards towards the mini-sac or outwards towards the nozzle exit in concert with the rotational flow in the mini-sac. The mini-sac bubbles’ internal pressure differences revealed that the bubbles must have contained previously dissolved oxygen and nitrogen. Under diesel engine operating conditions, this multi-phase mixture would be highly reactive and could initiate local pyrolysis and/or oxidation reactions. Finally, the dynamical behaviour of the diesel fuel in the nozzle holes would support the admission of external hot combustion gases into the nozzle holes, establishing the conditions for oxidation/pyrolysis reactions with surrounding liquid fuel films

Suatu Penelitian Tentang Kemampuan Siswa Kelas Dua SMA 2 Tambang dalam Menulis Teks Pengumuman

The purpose of this study is to find out the second year students' ability of SMA 2 Tambang in writing announcements. This research focuses on grammar, vocabulary, mechanic, form, and fluency based on writing announcements. The instrument used by the writer to collect the data for this study is writing test, that is writing announcements. Based on the research finding in SMA 2 Tambang, it can be found that, first, the ability of the students in writing announcements is in good level. Second, the students' mean score in grammar is 63, vocabulary is 68, mechanic is 65, fluency is 56, and form is 54.The highest score obtained by the students for vocabulary that in at good level, and the lowest score that the students got is for form at in mediocre level

Coverage and predictors of vaccination among children of 1-4 years of age in a rural sub-district of Sindh

OBJECTIVE: To estimate the proportion of children 1-4 years of age vaccinated in the first year of their life and determine socio-demographic factors associated with vaccination in the rural sub-district Khairpur, Sindh, Pakistan.STUDY DESIGN: Cross-sectional study.PLACE AND DURATION OF STUDY: The study was conducted in 9 Union Councils of sub-district Gambat, district Khairpur, Sindh, from August to October 2008.METHODOLOGY: A questionnaire based representative multi-stage cluster survey was conducted. A total of 549 children aged 1-4 years were assessed for coverage and predictors of vaccination. Univariate and multivariate analysis was done using logistic regression to determine the unadjusted and adjusted relationship between socio-demographic predictor and outcome (vaccination status).RESULTS: The coverage for complete vaccination was 71.9% (95%CI=68.1%-75.7%). Educational level of mother (p=0.042), father (p=0.001) and child birth at hospital (p=0.006) were significantly associated with the vaccination status. Mother\u27s educational level of intermediate and above was the strongest predictor (OR=12.19, 95%CI=1.57-94.3) for vaccination.CONCLUSION: Education of parents, particularly mother\u27s education was important determinant of vaccination status of the children. In addition, distance from taluka health facility and misconception of parents were among the main reasons of not getting the children vaccinated. There is a need to educate the parents especially mothers about the importance of vaccination and organize EPI services at Basic Health Unit level to improve the vaccination coverage in rural areas of Pakistan

Problem-Based Versus Conventional Curricula: Influence on Knowledge and Attitudes of Medical Students Towards Health Research

Background Medical education curricula in developing countries should emphasize training in health research. This study compares the knowledge and attitudes towards health research between undergraduate medical students undertaking Problem Based Learning (PBL) versus conventional Lecture Based Learning (LBL). Methods Two groups comprising 66 (LBL) and 84 (PBL) 4th and 5th year students from the medical college of Aga Khan University were administered a structured and validated questionnaire. Knowledge and attitudes of the two groups were recorded on a scale (graduated in percentages) and compared for statistical difference. Results PBL students scored 54.0% while LBL students scored 55.5% on the knowledge scale [p-value; 0.63]. On the attitudes scale, PBL students scored 75.5% against a 66.7% score of LBL students [p-value; 0.021]. A higher proportion of PBL students (89%) had participated in research activities compared to LBL students (74%) and thus felt more confident in conducting research and writing a scientific paper. Conclusion The PBL students showed slightly healthier attitudes towards health research compared to LBL students. Both groups demonstrated a similar level of knowledge about health research. The positive impact of the PBL curriculum on attitudes of medical students towards health research may help in improving research output from developing countries in future

The Impact of Sosiodemographic and Environmental Factor on Chikungunya Outbreaks at Cinere, Limo Sub District, Depok City in 2006

On october 2005, in Depok occured chikungunya outbreaks that attack 200 citizen at Cinere, Limo Sub District, Depok City. This study purpose is to know the impact of sosidemographic and enviromental factor on chikungunya outbreaks at Cinere, Limo Sub District, Depok City. Research design is case control study. The number of case group and control group is 118 patient. Factor studied are education, knowlwdge, house density, age, occupation, sex, mobility, anti-mosquito chemical, existance of mosquito-larva, container, and wire netting. The result of the study suggest that there are three variabels that involved in chikungunya outbreaks, namely education (OR=1,9: 1,12-3,23), age (OR= 2,1: 1,22-3,46), and house density (OR=2,2: 1,25-3,80). Multivariat analysis showed that the most dominant factors are house density, and followed by education. Probability of chikungunya outbreaks is 2,1 for low house density and low education

Correlates of morbidity and mortality in severe necrotizing pancreatitis

Acute severe pancreatitis is associated with a high morbidity and mortality and frequently is accompanied by underlying pancreatic parenchymal necrosis. Patients with pancreatic necrosis must be identified, because the morbidity and mortality rate in this subgroup is much higher. Our objective was to compare the clinical outcomes of these patients based on the degree of pancreatic necrosis. A total of 35 patients were noted to have pancreatic necrosis. These were divided into 2 groups based on extent of necrosis: group A had less than 50% necrosis and group B had more than 50% necrosis. The rate of mortality (5% versus 40%) was significantly higher in group B. The rate of organ dysfunction also rose along with the rates of other morbidities and variables that were related to a patient’s hospital stay. Only APACHE II significantly correlated with the degree of necrosis, wherein the chances of substantial necrosis rose by 20% with each unit increase of APACHE II score. APACHE II Score could be employed and studied further prospectively to help identify patients with pancreatic necrosis