Assessment Performance of 3-Parameter Probability ‎Distributions for At-site Annual Streamflow in the ‎Blue Nile Basin ‎

Many investigators have been applied various probability distributions for flood discharges at-site or region, however, there is no scientific judge about the best distribution to accurate the flood discharge estimations. In practice, different probability distributions are taken into account, and the best distribution is then applied to create the percentile quantiles. This paper introduces the assessment of three probability distributions that have three parameters; Generalized Extreme Value (GEV), Generalized Pareto (GPA) and Generalized Logistic (GLO) using L-moments (LM) method to estimate their parameters using annual peak discharge series of three hydrological stations on Blue River Basin and Atbara River in Sudan. Cunnane plotting position formula is considered to test the applicable probability distribution that gives good estimations in tails. The Q-Q relation with coefficient of determination (R2) is adopted to present the consistency process of the estimates and their corresponding of observed annual peak data. L-moment ratio diagram (LMRD) as suggested by Hosking and Walish (1993) is also performed to measure the discordance of probability distributions. Further, the evaluation performance of probability distributions can be measured by using three comparison criteria; root mean square error (RMSE), mean absolute deviation index (MADI) and relative root mean square error (RRMSE). The results indicated that GLO distribution generally shows the best fit followed by GEV distribution; however the GEV distribution gave more realistic in upper tail than others. It may be recommended as the appropriate probability distribution for annual peak discharge at-site in Blue Nile

Evaluation of the in-vitro synergistic potential of vancomycin combined with other antimicrobial agents against methicillin-resistant Staphylococcus aureus isolates

Background: Methicillin-resistant Staphylococcus aureus (MRSA) infection is a major public health problem, causing a wide range of infections including bacteremia. Infections caused by MRSA are associated with significant morbidity, mortality, and costs. The present study aimed to determine the frequency of MRSA isolates among bacteremic patients, to determine their antimicrobial susceptibility patterns and to evaluate the in-vitro synergy combinations of vancomycin plus imipenem, cefepime, cefazoline and piperacillin-tazobactam against these isolates. Methods: Fifty confirmed MRSA strains isolated from blood cultures constituted the material of this study. The BD Phoenix was used to determine the susceptibility of these isolates to different antimicrobials. The Two-agent Broth Microdilution checkerboard test was used to evaluate the effect of combinations of two antimicrobial agents on the studied isolates. Results: In the current study the prevalence of MRSA among bacteremic patients was 15.68%, resistance rate was as follow: Gentamicin (80%), erythromycin (68%), ciprofloxacin (64%), norfloxacin (52%), moxifloxacin (36%), trimethoprim-sulfamethoxazole (46%), doxycycline (38%), rifampin (34%), clindamycin (24%), chloramphenicol (8%), linezolid (6%), teicoplanin (2%). All isolates were fully susceptible to daptomycin and vancomycin. Synergy was seen in varying proportions of the MRSA isolates when vancomycin was combined with imipenem, piperacillin-tazobactam, cefepime and cefazolin that was 76%, 66%, 54% and 52% respectively. No antagonism was observed. The mean FIC indices for combination of Vancomycin with Imipenem were significantly inversely correlated with the vancomycin MICs of the isolates using linear regression analysis. Conclusions: The synergistic activity of vancomycin in combination with β- lactam antibiotics offers new insights in treatment options of serious MRSA infections

A quality assurance technique for the static multileaf collimator mode based on intrinsic base lines

AbstractThe inspection of the static leaf positions of Multileaf Collimator (MLC) devices is essential for safe radiotherapy deliveries in both static and dynamic modes. The purpose of this study was to develop a robust, accurate and generic algorithm to measure the individual static MLC leaf positions. This was performed by extracting leaf tip locations from the radiographic film image and measuring their relative distance from a reference line on the film. The reference line was created with a selected set of MLC leaf sides. The film scaling was created and verified using the physical leaf width. The average measured distance corresponds to a leaf width of 10 mm was 9.95 ± 0.09 mm. The estimated reproducibility of the leaf tips location was ±0.26 mm. The code accuracy was checked by intentionally positioning set of leaves with small errors (1 mm), and the detected deviations from the expected positions ranged from −0.25 mm and +0.32 mm. The algorithm includes two self testing functions in order to detect failures of leaf positioning due to poor film quality and to avoid the potential systematic errors attributable to the improper collimator setting. The code is promising to be more efficient with Gafchromic and Electronic Portal Imaging Device (EPID)

Properties of Copper nitride thin films deposited using a pulsed hollow cathode discharge

Copper nitride (Cu3N) thin films were deposited on a glass substrates using pulsed hollow cathode discharge (PHCD). The deposition was performed at 4kV charging voltage, and nitrogen gas pressure of 10-2 torr. The structure of the thin films was identified by X-Ray diffraction (XRD) technique. The XRD measurements indicated that the thin films have a nanocrystalline nature and exhibit orientation at (111) phase of Cu3N. The grain size of the nanocrystalline films ranged from 41 nm to 80 nm. The optical band gaps were measured using UV Visa NIR spectrophotometer and Touc's equation. The optical band gaps of the films decreased from 2.55 eV to 2.25 eV by increasing the number of deposition shots from 20 to 80 shots. The surface morphology was studied by scanning electron microscopy (SEM). The SEM image indicates that the film have facetted surface morphology packed particles

Monitoring and bioremediation of organochlorine pesticides in surface water with Enterobacter asburiae

Aim of study: One of the safest techniques regarding the remediation of contaminated water is biological remediation. This study aimed to: (i) monitoring of a collection of organochlorine pesticides (OCPs) in three agricultural drainages (Nashart, no. 9, and El-shoka), located in Kafr El-Sheikh governorate, Egypt; and ii) investigate the biodegradation potential of different bacterial isolates regarding organochlorine pesticides.Material and methods: Analysis of OCPs was carried out by gas chromatography, Enrichment cultures were used for isolation of the bacterial strains capable of OCPs biodegradation and the most efficient isolate was identified based on morphological, biochemical ad molecular characteristics.Main results: The determination of OCPs in water samples by gas chromatography showed varying values of OCPs ranging from 0.0 mg/L (below detection limit) to 0.0385 mg/L. A total of four morphologically different bacterial isolates were obtained, which showed a remarkable capability of OCPs biodegradation detected in mineral salt medium containing 17 OCPs active ingredients by two approaches including the analysis of the OCP residues at the end of the incubation period and measuring the bacterial growth in terms of total viable count and optical density. The bacterial isolate N2 showed the highest degradation capability when the screening process was carried out to select the most efficient isolates, which was identified according to the morphological, biochemical and molecular characterization as Enterobacter asburiae.Research highlights: The biodegradation of OCPs using E. asburiae was proved to be a promising approach for the detoxification and removal of OCPs residues in aqueous systems

(A) Study on the Agadir agreement as the gateway to establish a pan-arab free trade area

Thesis(Master) --KDI School:Master of Public Policy,2010masterpublishedby Mohamed Tolba

Molecular diversity and genetic organization of antibiotic resistance in Klebsiella species

Klebsiella spp. are opportunistic pathogens that cause hospital and community acquired infections such as pneumonia, urinary tract infection, septicaemia, soft tissue infections, liver abscess, and meningitis. Multidrug-resistant strains possessing extended-spectrum β-lactamases (ESBLs) has become an increasing problem worldwide. The over use and, in some cases, misuse of antibiotics in humans and in animal husbandry has been cited as a responsible factor in the development of drug resistance in all bacterial species. The advancing age; female gender, hospital crossinfection, the food chain trade and human migrations have contributed to increase the risk for community-acquired ESBL. A total of 223 isolates collected in 2006 and 2007 at Royal Infirmary of Edinburgh, Scotland, 219 K. pneumoniae, 2 K. oxytoca, 1 Enterobacter cloacae, and one isolate Salmonella enterica were identified by API 20E and confirmed genotypically with gyrA PCR-RFLP method. The antimicrobial susceptibility results showed that 34 (15.2%), 36 (16.1%), 35 (15.7%), 45 (20.2%), 30 (13.5%) and 55 (24.7%) of these strains were found to be resistant to cefotaxime, ceftazidime, ceftriaxone, naladixic acid, ciprofloxacin and cefoxitin. None of the isolates were found resistant to meropenem keeping carbapenems the drug of choice for the treatment of multiresistant isolates. The overall frequency of ESBL producers observed in this study was 35 (15.7%) most of them 32/35 (91.4%) were from K. pneumoniae. The genetic analysis showed that SHV β-lactamases were detected in 32, whereas TEM and CTX-M were detected in 24 and 16 respectively. From the ESBL-producing isolates, molecular methods identified nine strains possessing ESBL-SHV genes (1 strain blaSHV-5, 1 strain blaSHV-80 and 8 strains blaSHV-12), whereas the remaining were from the “non-ESBL” producing strains. Conjugation methods demonstrated that 29/32 isolates harboured transferable blaSHV genes. The large SHV transposon-borne promoters were amplified from only one non-transferable blaSHV-11, 15 isolates produced the small SHV transposon-borne promoters. Furthermore, the IS26 was found 73bp upstream of the blaSHV gene in all small SHV transposon-borne promoters. A new blaLEN gene was identified from K. pneumoniae (KpII) phylogenetic group but remained susceptible to all cephalosporins. Sixteen (7.3%) of K. pneumoniae isolates were found to be producers of the CTX-M- 15 ESBL, of which two isolates (12.5%) were reported to be from communityacquired infections. The insertion sequence ISEcp1 was detected by sequencing 48 nucleotides upstream of blaCTX-M-15 in all isolates but one. Five different clones of CTX-M-15-producing isolates were identified by PFGE. The findings indicated a higher prevalence of qnr genes than in previous studies but still low in general. By PCR, 18 (8%) (11 qnrB1, 2 qnrB6 and 5 qnrA1) genes were identified from K. pneumoniae isolates. Also, the findings indicated the frequent coexpression of fluoroquinolones and ESBLs resistance in the same isolate. Two K. oxytoca strains were isolated from urine and blood specimens of hospitalized patients. Both strains were positive for the blaOXY-2 gene. One strain showed resistance to pencillins, monbactams, cephalosporins including cefotaxime and ceftazidime but was not inhibited by clavulanic acid. It differed by an amino acid substitution Ala237→Thr, which enhances the binding of cefotaxime. S1-nuclease plasmid profiles were obtained for some isolates. A total of one to two plasmids, ranging in size from approximately 40 to 210 kb, were observed per strain. The plasmids from 24 ESBL K. pneumoniae strains were assigned to be IncN or IncFII replicons. Analysis of phylogenetic groups showed that the majority of K. pneumoniae isolates were belonged to KpI-type. Both K. oxytoca strains were assigned to be KoII phylogenetic group based on rpoB and gyrA sequencing. Integrons are capable of capturing and mobilizing genes called gene cassettes which play an important role in the dissemination of antimicrobial resistance through horizontal transmission. In fact, the present study indicated a high frequency of occurrence of class 1 integrons among ESBL-positive K pneumoniae. Three isolates positive for class 1 integrons were found positive for class 2 integrons as well. Class 1 integrons including dfr, aadA and ereA2 gene cassettes have been identified by sequencing, which confer resistance to trimethoprim, streptomycin/spectinomycin and erythromycin respectively. In conclusion, the results from this thesis report the emergence of hospital and community-acquired highly resistant CTX-15 β-lactamase in the Edinburgh, Scotland. The prevalence of ESBL-producing isolates in Scotland is still much lower than in many other European countries. The dissemination of SHV- and TEM- β- lactamase types in this study is more predominate than CTX-M-15

Assessment of lacrimal glands in thyroid eye disease with diffusion-weighted magnetic resonance imaging

Purpose: To assess the lacrimal glands in patients with thyroid eye disease with diffusion-weighted magnetic resonance (MR) imaging. Material and methods: This study was carried out on 44 consecutive patients (17 males, 27 females, with mean age 36 years) with thyroid eye disease and 20 age- and sex-matched volunteers. They underwent diffusion-weighted MR imaging of the orbit. The apparent diffusion coefficient (ADC) values of the lacrimal glands were calculated and correlated with the clinical activity score (CAS). Results: The mean ADC of lacrimal glands in thyroid eye disease (1.73 × 10-3 mm2/s) was significantly higher (p = 0.001) than that of volunteers (1.52 × 10-3 mm2/s). The cutoff ADC value of lacrimal gland used for differentiation of thyroid eye disease from volunteers was 1.62 × 10–3 mm2/s with an area under the curve value of 0.95 and an accuracy of 96%. There was significant difference (p = 0.03) in the ADC of the lacrimal glands in patients with active (n = 24) and inactive (n = 20) disease. The cutoff ADC value of the lacrimal gland used to suspect active disease was 1.76 × 10-3 mm2/s with an area under the curve value of 0.80 and an accuracy of 82%. There was positive correlation between the ADC value of the lacrimal glands and CAS (r = 0.73, p = 0.001). Conclusions: The ADC of the lacrimal glands is a non-invasive imaging parameter that can be used for diagnosis of thyroid eye disease and to predict the active form of the disease

Assessment of the relationship between serum soluble Klotho and carotid intima–media thickness and left ventricular dysfunction in hemodialysis patients

AbstractBackgroundThe aim of our study was to assess the relationship between soluble Klotho (s-Klotho) and carotid intima–media thickness (CIMT) and left ventricular (LV) dysfunction in hemodialysis (HD) patients.MethodsThis is a cross-sectional study conducted on 88 patients with end-stage renal disease on regular HD. Serum levels of calcium, phosphorus, parathyroid hormone, and C-reactive protein were measured. The serum levels of s-Klotho and fibroblast growth factor-23 (FGF-23) were measured using an Enzyme linked immunosorbent assay (ELISA) kit. Echocardiography and measurement of CIMT were also conducted. The studied patients were divided according to the median s-Klotho level into 2 groups: patients with low s-Klotho (Group I) and patients with high s-Klotho (Group II).ResultsMean value of s-Klotho was significantly low in HD patients compared to controls (P = 0.001), and mean value of FGF-23 was significantly high in HD patients compared to controls (P = 0.001). The mean values of parathyroid hormone, FGF-23, and phosphorus were significantly high in Group I compared to Group II, whereas the mean value of serum calcium was significantly low in Group I compared to Group II. The mean values of CIMT, LV mass (LVM), LVM index, and LV ejection fraction (LVEF) were high in Group I compared to Group II. Patients with low s-Klotho had significantly more coronary artery disease (CAD). In a regression analysis of s-Klotho with different markers of cardiovascular diseases, s-Klotho showed significant association with CIMT, LVEF, and CAD, but not with LVM and LVM index.ConclusionThe present study showed that patients with a low s-Klotho were more often associated with increased CIMT, LV dysfunction, and CAD, and it seems that there was independent association between s-Klotho and CIMT, LVEF, and CAD

Non-invasive Hemodynamic Monitoring of Fluid Resuscitation in Cirrhotic Patients with Acute Kidney Injury

BACKGROUND: Fluid management of patients with liver cirrhosis and acute kidney injury (AKI) is a complex problem requiring accurate assessment of the intravascular volume status and the cause of the AKI. Echocardiography used in various hemodynamic monitoring as a quick, easy, bedside, and non-invasive tool with great sensitivity. AIM: This study aims to evaluate echocardiography as a non-invasive hemodynamic monitoring tool for the assessment of volume status and cardiac function before and after volume expansion in patients with liver cirrhosis presented by AKI. PATIENTS AND METHODS: This study included 120 patients with liver cirrhosis and AKI. All patients were subjected to clinical evaluation, laboratory assessment of kidney and liver functions, and echocardiographic assessment of inferior vena cava (IVC) collapsibility index, left ventricular outflow tract velocity time integral (LVOT VTI) variability index, and cardiac output (CO). RESULTS: Comparison between responders and non-responders to volume resuscitation regarding the echocardiographic data showed that responders had significantly higher IVC collapsibility index, LVOT VTI variability index, and % of CO increase. IVC collapsibility index and LVOT VTI variability index showed good predictive value of fluid responsiveness. CONCLUSIONS: The use of echocardiography is a good tool for hemodynamic monitoring of fluid resuscitation in cirrhotic patients with AKI. The use of echocardiography has limited the use of central venous line only to patients with hemodynamic instability requiring vasoactive support