606 research outputs found

    Modelling of reservoir network for flood control using nonlinear reservoir routing model

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    Network of reservoirs has become a standard hydraulic construct for multipurpose use. In this work, we present a formulation based on nonlinear reservoir method and coupled tank approach to model the reservoir network for flood control. The network of reservoirs consists of both detention and retention pond which give rise to nonlinear system of ODE for the m reservoirs in the network. The inflow consists of rainfall runoff in each sub catchment and discharges from the adjacent reservoirs. On the other hands, the outflow consists of infiltration and discharges. The nonlinear system obtained is linearized about the normal operating height of each reservoir in the network. The discharge term on the last equation is dropped in order to allow all the runoff captured into it. The establishment of relationship between the area of catchment and area of reservoir give room for the estimation of the forcing function in terms time of concentration rather than in terms of area of the reservoir which is difficult to obtain in an existing network. Two sets of solutions are presented, one at the convergent point and the other the best solution in respect of the lowest point in the reservoirs

    NON-AQUEOUS TITRIMETRIC ASSAY OF GABAPENTIN IN CAPSULES USING PERCHLORIC ACID AS TITRANT Non-aqueous titrimetric assay of gabapentin in capsules using perchloric acid as titrant

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    Two simple, rapid, accurate and inexpensive methods using visual and potentiometric titrimetric techniques are described for the determination of gabapentin (GBP) in bulk drug as well as in capsules. The methods are based on the neutralization reaction of the primary amino group of GBP with acetous perchloric acid as titrant in anhydrous acetic acid medium. The end point was detected either visually using crystal violet as indicator or potentiometrically using a modified glass electrode SCE electrode system. Both methods are applicable over the range 1.0-16.0 mg of GBP and the titration reaction follows a 1:1 stoichiometry. The methods were successfully applied to the determination of GBP in capsules. The validity of the proposed methods was further ascertained by parallel determination by a reference method and by recovery studies via standard-addition technique

    Utilization of bromination reactions for the determination of carbamazepine using bromate-bromide mixture as a green brominating agent

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    One titrimetric and two spectrophotometric procedures have been developed for the assay of carbamazepine (CBZ) in bulk drug, formulations and spiked human urine. The methods are based on the bromination of CBZ by the bromine generated in situ by the action of the acid on the bromate-bromide mixture. The twin advantages of avoiding liquid bromine and analysis in a cost-effective manner are realized. In titrimetry, the drug was treated with a known excess of bromate-bromide mixture in hydrochloric acid medium followed by the determination of unreacted bromine iodometrically. Spectrophotometry involves the addition of a measured excess of bromate-bromide reagent in acid medium to CBZ, and after the reaction is ensured to be complete, the residual bromine was determined by reacting with a fixed amount of either methyl orange and measuring the absorbance at 510nm (method A) or indigo carmine and measuring the absorbance at 610nm (method B). Titrimetric procedure is applicable over the range of 1.00-7.50mg CBZ, and the calculations are based on a 1:1 reaction stoichiometry (CBZ:KBrO3). In spectrophotometric methods, Beer's law is valid within concentration ranges of 0.25-1.50 and 0.50-6.00μgml-1 CBZ for methods A and B, respectively. The proposed methods were successfully applied to the determination of CBZ in tablets and syrup, in addition to spiked human urine by the spectrophotometric methods, with mean recoveries of 95.50-104.0% and the results were statistically compared with those of an official method by applying Student's t-test and F-test

    Spectrophotometric Determination of Mycophenolate Mofetil as Its Charge-Transfer Complexes with Two π-Acceptors

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    Two simple, selective, and rapid spectrophotometric methods are described for the determination of mycophenolate mofetil (MPM) in pure form and in tablets. Both methods are based on charge-transfer complexation reaction of MPM with p-chloranilic acid (p-CA) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dioxane-acetonitrile medium resulting in coloured product measurable at 520 nm (p-CA) or 580 nm (DDQ). Beer's law is obeyed over the concentration ranges of 40–400 and 12–120 μg mL−1 MPM for p-CA and DDQ, respectively, with correlation coefficients (r) of 0.9995 and 0.9947. The apparent molar absorptivity values are calculated to be 1.06 × 103 and 3.87 × 103 L mol−1 cm−1, respectively, and the corresponding Sandell's sensitivities are 0.4106 and 0.1119 μg cm−1. The limits of detection (LOD) and quantification (LOQ) are also reported for both methods. The described methods were successfully applied to the determination of MPM in tablets. Statistical comparison of the results with those of the reference method showed excellent agreement. No interference was observed from the common excipients present in tablets. Both methods were validated statistically for accuracy and precision. The accuracy and reliability of the methods were further ascertained by recovery studies via standard addition procedure

    Biofuel From Cow Tallow: A Case Study

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    The global demand for energy in recent decade has been dramatic. Indeed, several oil and gas reservoirs around the world are depleted every day. Moreover, the fossil fuels for example, petroleum emitted huge quantities of toxic gases to the environment. Therefore, the passive environmental consequences of fossil fuels and the bother about fossil fuel supplies have encouraged the investigation for renewable biofuels. Thus, this work is objective to produce a biodiesel fuel from residual cow tallow that produced every day at Koya city slaughterhouse. The Koya slaughterhouse cow tallow may consider low cost renewable feed stock to produce biodiesel. Furthermore, the study has examined various process parameters for example, catalyst amount and alcohol amount as well on fuel production yield. The produced biodiesel is also subjected into several tests for instance, density and cetane number

    Association Between Race/Ethnicity and Survival of Melanoma Patients in the United States Over 3 Decades

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    Melanoma is a treatable and preventable skin cancer. It is responsible for 75% of deaths among all skin cancers. Previous studies have found that race/ethnicity may play a role in survival among melanoma patients. However, there are no studies that cover 30 years and take race into account for the U.S. population. This study is a secondary analysis of the National Cancer Institute\u27s Surveillance, Epidemiology, and End Result (SEER) Program. Adults with primary cutaneous melanoma from 1982 to 2011 were included; the final sample size was 185,219. The outcome was survival; both cause-specific and all-cause mortality were examined. The main exposure was race/ethnicity. Kaplan?Meier survival analysis was used to estimate overall survival. Cox proportional hazards regression was used to estimate unadjusted and adjusted hazard ratios (HRs). A P-value less than 0.05 was considered statistically significant. More than 50% of patients in all races/ethnicities were diagnosed at the in situ or localized stage. Non-Hispanic White patients were more frequently diagnosed at the in situ stage. Overall, more men were diagnosed than women. The majority of cases among all races were men. Non-Hispanic Black females represented the smallest percentage of melanoma cases among all races. The smallest number of diagnoses across all races/ethnicities was made from 1982 to 1991. Median follow-up was 81 months and no collinearity was observed in the adjusted models. When examining cause-specific mortality and controlling for site and stage at diagnosis, gender, age and decade of diagnosis, the HR for non-Hispanic Black patients was lower than that for non-Hispanic White patients (HR 0.7; 95% confidence interval (CI): 0.6?0.8). However, when examining all-cause mortality, this difference disappeared (HR 1.1; 95% CI: 1.0?1.2). Stage at diagnosis impacted HR; patients diagnosed with distant metastases had significantly worse survival. When taking cause-specific mortality into consideration and after controlling for stage and site at diagnosis, gender, and age and decade of diagnosis, non-Hispanic Black patients had a lower HR compared to non-Hispanic White patients. However, this difference disappeared when examining all-cause mortality. Further research is needed to explore this finding and to determine what factors may be associated with late-stage melanoma diagnosis

    Prescribing patterns of gastrointestinal drugs in private clinics in Benghazi-Libya

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    Background: Prescription analysis can pinpoint areas of improvement in encounters issued by prescribing physicians. The present study was carried out to analyze prescribing trends for outpatients among consultants in the city of Benghazi-Libya.Methods: A total of 4000 prescriptions were collected from private pharmacies around the city of Benghazi, Libya. Indicators addressed included the patient's name, age, sex, and address, and the physician's name, address, and signature. The percentage of prescriptions lacking this information was calculated. Drugs prescribed by dosage, duration of treatment were also considered. The study focused on the commonly prescribed classes of gastrointestinal drugs and the most frequently prescribed drug of each common class. No attempt was made to evaluate the incidence of various gastrointestinal disorders. Results are expressed as frequency and percentage of prescribed medicines.Results: Information present in prescriptions and pertaining to the patient were name (2972, 74.3%), age (468, 11.7%), date of visit (107, 2.7%) while those for prescriber were name (1902, 47.6%) and signature (3612, 90.3%). None of the prescriptions contained sex of patient, his/her address, or registration number of the prescriber. All prescribed drugs were in brand names. Polypharmacy was not evident as all prescriptions contained 1-2 drugs.The number of prescriptions with a gastrointestinal drug(s) counted to 421 (10.5%) out of the total 4000 prescriptions. The most commonly prescribed classes of gastrointestinal drugs include in order, anti-hyperacidity, anti-emetics, anti-spasmodic, laxatives and anti-diarrheal with the most frequently prescribed drug of each therapeutic class being omeprazole (67, 48.9%), metoclopramide (57, 57%), hyoscine-N-butyl bromide (42, 55.3%), bisacodyl (44, 59.5%) and loperamide (30, 88.3%) respectively.Conclusions: The results of the present study indicate the need to improve prescribing among physicians, a task that can be achieved through inclusion of related topics such as prescription writing and rational drug use in undergraduate curricula and continuing medical educational programs

    Enhanced Recovery After Surgery (ERAS) Protocols In General Surgery: A Review Of Implementation And Outcomes

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    ERAS is a group of protocols that aim at affecting positively patients & surrounding lives. surgeons, nurses, physiotherapists, anesthetists, and even healthcare centers hospitals, labs, and pharmacies. Reducing the cost for both hospitals &patients, decreasing the duration of residency in hospitals, and improving patient compliance, developing performance & increasing teamwork between medical staff and patients all fall under the advantages of ERAS. Since it affects the 3 stages of any operation (preoperative-intraoperative-perioperative) it was necessary to implement a suitable protocol for each patient to achieve the best results mostly quitting smoking, fasting for a period before surgery, maintaining body temperature, pressure, and glucose level and the postoperative instructions , care & nutrition to guarantee success and avoidance to recurrence or complications

    Hepatitis C virus infection in Nigerians with diabetes mellitus

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    ABSTRACT It has been reported from several Caucasian studies that there is an epidemiological association between hepatitis c virus infection and diabetes mellitus. The objective of this study was to determine whether any such relationship exists in a black African population. To determine the prevalence of Hepatitis C virus infection in Nigerians with diabetes mellitus in North-Eastern Nigeria. Hospital -based cross-sectional study. Medical out-patient clinic and the Blood bank of the Federal Medical Centre, Yola. Nigeria. From June, 2008 to December 2009, Two hundred and eighty consecutively recruited diabetes mellitus patients comprising 108 males and 172 females were screened for HCV infection. These were compared with five hundred and ninetyfive voluntary blood donors who were screened during the same period. Serological testing for HCV infection was carried out with anti-HCV using Enzyme Linked Immuno-sorbent Assay (ELISA) method. The bio-data of the patients, history and duration of diabetes mellitus, history of jaundice, blood transfusion were recorded on a proforma. Out of the 280 diabetes mellitus patients tested, twenty-six were positive for anti-HCV antibodies giving an infection rate of 9.3% compared with fourteen subjects out of 595 voluntary blood donors 2.4% (p=0.0000105). History of blood transfusion, and jaundice was positively correlated with presence of HCV infection in diabetic patients. Hepatitis C virus is more common in Nigerian patients with diabetes mellitus than in non-diabetic control subjects. It may be necessary to screen patients with diabetes mellitus for hepatitis c virus infection particularly those with history of blood transfusion and jaundice

    A phased SNP-based classification of sickle cell anemia HBB haplotypes

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    Background: Sickle cell anemia causes severe complications and premature death. Five common beta-globin gene cluster haplotypes are each associated with characteristic fetal hemoglobin (HbF) levels. As HbF is the major modulator of disease severity, classifying patients according to haplotype is useful. The first method of haplotype classification used restriction fragment length polymorphisms (RFLPs) to detect single nucleotide polymorphisms (SNPs) in the beta-globin gene cluster. This is labor intensive, and error prone. Methods: We used genome-wide SNP data imputed to the 1000 Genomes reference panel to obtain phased data distinguishing parental alleles. Results: We successfully haplotyped 813 sickle cell anemia patients previously classified by RFLPs with a concordance >98%. Four SNPs (rs3834466, rs28440105, rs10128556, and rs968857) marking four different restriction enzyme sites unequivocally defined most haplotypes. We were able to assign a haplotype to 86% of samples that were either partially or misclassified using RFLPs. Conclusion: Phased data using only four SNPs allowed unequivocal assignment of a haplotype that was not always possible using a larger number of RFLPs. Given the availability of genome-wide SNP data, our method is rapid and does not require high computational resources.NIH Bethesda, MDBoston Univ, Sch Med, Dept Med, 72 E Concord St, Boston, MA 02118 USABoston Univ, Bioinformat Program, Boston, MA 02215 USAKing Saud Univ, Coll Med, Sickle Cell Dis Res Ctr, Riyadh, Saudi ArabiaKing Saud Univ, Coll Med, Dept Pediat, Riyadh, Saudi ArabiaKing Faisal Univ, Al Omran Sci Chair, Al Hasa, Saudi ArabiaImam Abdulrahman bin Faisal Univ, Inst Res & Med Consultat, Dammam, Saudi ArabiaEscola Paulista Med, Hematol & Blood Transfus Div, São Paulo, BrazilBoston Univ, Sch Publ Hlth, Dept Biostat, Boston, MA 02118 USAEscola Paulista Med, Hematol & Blood Transfus Div, São Paulo, BrazilNIH: R01 HL 068970NIH: RC2 HL 101212NIH: R01 87681NIH: T32 HL007501Web of Scienc
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