Numerical investigation of sand erosion rate in a horizontal axis wind turbine.

Renewable energy represents an important alternative solution for many energy problems nowadays and a tool for a healthier environment by reducing carbon footprints resulting from burning fossil fuels. However, more work needs to be done towards maximizing the energy produced from renewable energy methods and making sure that the infrastructure used stays in service for a longer duration. Sand erosion phenomena is responsible for the degradation of the wind turbine blades and hence the decrease in their performance and life. In the current research, a numerical study of both performance and sand erosion of a Small-Scale Horizontal Axis Wind Turbine (SS-HAWT) is carried out. This study introduces new sights of instantaneous and forecasted erosion rates within the blade of the wind turbines. Three-dimensional E216 airfoil blades of radius 0.5 m are established according to blade element momentum theory. Sand particles with different mass flow rates of 0.001, 0.002 and 0.003 kg/s and uniform diameters of 50, 100 and 200 µm have been selected as eroding particles under two different average air velocities of 8 m/s and 10 m/s. The results indicate that the performance of wind turbines is enhanced as the flow separation at the suction side is shifted to the trailing edge. Furthermore, the optimum tip speed ratio is about 5 at an air velocity of 8 m/s with a power coefficient of 0.432. In terms of erosion findings, V-shaped scars are reported near the leading edge of the blades. In addition, the instantaneous erosion rate grows exponentially with the tip speed ratio. Therefore, the yearly prediction of maximum erosion depth at the optimum operating conditions is obtained to be 5.7 mm/year in some spots of the turbine blades.

Twin penile skin flap, is it the answer for repair of long anterior urethral strictures?

OBJECTIVE: To present our twin ventral penile skin flap technique for the management of complex long anterior urethral strictures not caused by lichen sclerosis (LS), with evaluation of surgical outcome and complications. PATIENTS AND METHODS: We retrospectively reviewed patients diagnosed with long complex anterior urethral strictures who were all referred to Ain Shams University hospital and operated on by three reconstructive surgeons. The surgical procedure was carried out as follows: exposure of the urethra through a ventral longitudinal penile skin incision and another perineal incision; two ventral longitudinal dartos-based penile skin flaps are used for urethral augmentation as onlay flaps. Clinical data were collected in a dedicated database. Preoperative, intraoperative, and postoperative follow-up data for each patient were recorded and analysed. A descriptive data analysis was performed. RESULTS: Between January 2012 and February 2015, 47 patients diagnosed by urethrograms as having long anterior urethral strictures, with a mean (SD, range) length of 17.56 (2.09; 14-21) cm, were managed by twin penile skin flap repair. Four patients were lost to follow-up, thus 43 patients constituted the study cohort. The mean (range) follow-up period was 31 (22-36) months. The overall success rate was 95.35% (41/43). At 12-months postoperatively, the 41 successful cases had a mean (SD, range) peak urinary flow rate of 20.26 (3.06, 14-25) mL/s and American Urological Association Symptom Score of 5.6 (1.85, 3-8). Postoperative complications included urethrocutaneous fistula in three patients (6.97%), mild sacculation of the flap in seven patients (16.52%), post-micturition dribbling in 34 patients (79.07%), decreased penile girth in two patients (4.65%), and chordae of <15° with no need for repair in three patients (6.97%). CONCLUSIONS: In the presence of a favourable urethral plate and ample non-hirsute penile skin, one-stage twin penile skin flap urethroplasty provides excellent results for non-LS related complex strictures, with minimal acceptable complications. It proved to be especially efficient in circumcised patients.

Follicular output rate can predict clinical pregnancy in women with unexplained infertility undergoing IVF/ICSI: a prospective cohort study.

This study aimed to determine whether follicular output rate (FORT) can predict the clinical pregnancy rate in women with unexplained infertility undergoing IVF/ICSI. This was a prospective study conducted at Dar El Teb subfertility centre in Cairo between June 2014 and July 2016. A total of 303 women with unexplained infertility, who were undergoing IVF/ICSI, were divided into three groups according to FORT tertile values. FORT was calculated as pre-ovulatory follicle count/antral follicle count × 100. There was a progressive and significant increase from the low to the high FORT groups in the clinical pregnancy rate (29.9%, 43.3% and 57.8%; P < 0.001), number of retrieved oocytes (5.4 ± 1.5, versus 6.8 ± 2.8, and 7.4 ± 2.1; P < 0.001), and fertilization rate (48.4 ± 21.8 versus 55.3 ± 20.3 and 57.4 ± 19.2; P = 0.006). Multivariate logistic regression analysis revealed that the correlation between FORT and pregnancy was independent of potential confounding factors (P = 0.008). We concluded that FORT is an independent variable affecting the clinical pregnancy rate in IVF/ICSI cycles. Higher FORT values had better oocyte yield and clinical pregnancy rates in women with unexplained infertility undergoing IVF/ICSI with potentially normal ovarian response.

ANTIMICROBIAL ACTIVITY FOR EXCRETION AND SECRETION OF THE GREENBOTTLE FLY LARVAE LUCILIA SERICATA (MEIGEN) (DIPTERA: CALLIPHORIDAE).

Sterile larval excretion/secretion (ES) exhibited antibacterial activity against some species of bacteria. They were shown to inhibit the growth of Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis Gram-negative bacteria Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae and Fungi Geotricum candidum and Aspergillus fumigatus thus exhibited limited inhibitory effect towards Gram-positive bacteria Streptococcus pyogenes and Staphylococcus epidermidis and Gram-negative Proteous vulgaris and Fungi Syncephalastrum racemosum, Candida albicans, that effect was slowed down when challenged with secretion on a solid media but no zone of complete inhibition was detectqd. Growth inhibiting activity was determined in liquid growth media using the Gram-positive, Gram-negative bacterial and fungal strains as indicator organisms.

REPELLENT EFFECT OF OCIMUM BASILICUM AND GLYCYRRHIZA GLABRA EXTRACTS AGAINST THE MOSQUITO VECTOR, CULEX PIPIENS (DIPTERA: CULICIDAE).

Essential or volatile oils of plants have been variously reported to have many medicinal applications. Methanol, acetone and petroleum ether extracts of Ocimum basilicum and Glycyrrhiza glabra were screened for their repellency effect against Culex pipiens mosquito. The repellent action of the present plants extracts were varied depending on the solvent used and dose of extract. Methanol extract of O. basilicum exhibited the lowest repellent activity as it recorded 77.4% at 6.7mg/cm2. The petroleum ether and acetone extract of 0. basilicum showed repellency of 98.1 & 84.6% respectively, at dose of 6.7mg/cm2, while methanolic extract of G. glabra recorded 73.8 & 50.3% at dose of 6.7 &1.7mg/cm2 respectively, the petroleum ether and acetone extract of G. glabra showed repellency of 76.3 & 81.6%, respectively at dose of 6.7mg/cm2, compared with the commercial formulation, N.N. diethyl toulamide (DEET) which exhibited 100% repellent action at dose of 1.8mg/cm2, respectively. The results may contribute to design an alternative way to control mosquitoes currently based on applications of synthetic insecticides. These extracts could be developed commercially as an effective personal protection meaure against mosquito bites and thus to control diseases caused by mosquito-borne pathogens.

Monitoring of the antiviral potential of bee venom and wax extracts against Adeno-7 (DNA) and Rift Valley fever virus (RNA) viruses models.

This study monitored the antiviral potential of bee venom and four wax extracts, ethanol white and black beeswax (EWW/EBW) and acetone white and black beeswax (AWW/ABW) extracts. Two different virus models namely Adeno-7 as DNA model and RVFV as RNA virus models. End point calculation assay was used to calculate virus depletion titer. The depletion of viral infectivity titer of ABW to Adeno-7 virus showed strong antiviral activity recorded a depletion of viral infectivity titer (1.66 log (10)/ ml) that gave equal action with bee venom and more than interferon IFN (1 log (10)/ ml). On the other hand, antiviral activity of EBW showed a moderate potential, while AWW showed no antiviral activity. Finally EWW showed synergetic activity against Adeno-7 virus activity. Thus, activity of wax extracts to RVFV was arranged in order of IFN bee venom > AWW & EBW > EWW and ABW recorded 3.34, 0.65, 0.5, 0.34 respectively. It is the first time to study the beeswax effect against DNA and RNA virus' models; acetone black beeswax recorded a depletion titer 1.66 log (10)/ml.

The using of Lucilia cuprina maggots in the treatment of diabetic foot wounds.

In the present study, Lucilia cuprina maggots were used for the treatment of diabetic foot wounds. An artificial wound was made in diabetic foot of rabbit. The maggots were sterilized and put directly on the wound after dressing the wound without using any antibiotics. Several cycles of maggots were put on the wound. The present results showed that the treatment of the diabetic foot was observed after 13 days. After this period the wound was completely healed and become free of microbial contamination. The new tissues were observed to close the wound.

Repellent effect of Lagenaria siceraria extracts against Culex pipiens.

Ethanolic, acetone and petroleum ether extracts from leaves and stems of Lagenaria siceraria (Cucurbitaceae) were screened for their repellency effect against Culex pipiens L. mosquito. The repellent action of the present plant extracts were varied depending on the plant parts and the dose of extract. The petroleum ether extract of leaves showed the same repellency percent (100%) of commercial formulation, N. N.diethyl toulamide (DEET) at the higher dose (3.33 mg/cm2), while petroleum ether extract from stems exhibiting the repellent action (89.6%) at the same dose, respectively. Ethanolic extracts of leaves and stems exhibited the lowest repellent activity as it recorded (81.3% and 69.1%) at (6.67 mg/cm2), respectively. Results of this study may contribute to design an alternative way to control mosquitoes currently based on applications of synthetic insecticides. These extracts could be developed commercially as an effective personal protection measure against mosquito bites and thus to control diseases caused by mosquito-borne pathogens.

Effects of midgut bacteria and two protease inhibitors on the reproductive potential and midgut enzymes of Culex pipiens infected with Wuchereria bancrofti.

Laboratory investigations were carried out to asses the effect of some proteases inhibitors on the reproductive potential of Culex pipiens females resulted from larvae treated with different protease inhibitors. The fecundity and engorgement of symbiotic and aposymbiotic C. pipiens females were significantly reduced. The blood meal digestion period increased significantly. On the other hand, enzyme band with molecular weight of 40 KDa which may be cysteine protease was detected in untreated symbiotic and aposymbiotic female midguts. The results may explain that the absence of this enzyme bands in treated female midguts may be due to the inhibition caused by (E-64) a cysteine protease inhibitor.

Effects of midgut bacteria and two protease inhibitors on the transmission of Wuchereria bancrofti by the mosquito vector, Culex pipiens.

Laboratory investigations were carried out to study the effect of two protease inhibitors on the transmission of W. bancrofti filarial by Culex pipiens and to study the susceptibility interaction between filaria and protease inhibitors. The results obtained revealed that, infection rates were variable among untreated and treated symbiotic and aposymbiotic Cx. pipiens females resulted from third instar larvae treated with E-64 and EDTA. The survival rate was variable among untreated and treated symbiotic and aposymbiotic females resulted from third instar larvae treated with E-64 and EDTA. Protease inhibitor (E-64) caused inhibition of the parasite development and transmission by means of ceasing catalytic activity- responsible for parasite migration-caused by parasitic larval stages inside the mosquito vector.

The ultrastructure of sensilla associated with mouthparts and antennae of Lucilia cuprina.

Antennal and maxillary palps of Lucilia cuprina male and female (family: Calliphoridae) were studied using scanning electron microscopy. Five types of sensilla were observed namely: trichoid, basiconic, coeloconic, styloconic and sensory pit. Trichoid sensilla (one subtype: short trichoid sensilla) was found on the scape of the antenna, while both trichoid (two subtypes: short and long trichoid sensilla) and styloconic sensilla were observed on the antennal pedicel. Basiconic sensilla (two subtypes: small and large basiconic sensilla), coeloconic sensilla and sensory pits were detected on the flagellum of antenna. Cheatica (two subtypes: small and large Cheatica) and small basicinic sensilla were located on the maxillary palps. Microtrachia were observed on all joints of antenna and maxillary palps. No marked differences were observed in the morphological structure of any of the sensilla among the two sexes studied. The suggested function of each antennal sensillum was based on comparison with results of other investigations on similar sensilla.

Voltammetric and spectroscopic studies on binding of antitumor Morin, Morin-Cu complex and Morin-beta-cyclodextrin with DNA.

A systematic comparative study of the binding of antitumor Morin and its complexes with DNA has been investigated in the Britton-Robison (BR) buffer solutions using voltammetric and spectroscopic methods. The results show that Morin molecule, acting as an intercalator, is inserted into the cavity of the beta-cyclodextrin (beta-CD) as well as into the base stacking domain of the DNA double helix. The interaction of Morin-Cu complex or the inclusion complex of Morin-beta-CD with ds-DNA causes hypochromism in the absorption spectra, along with pronounced changes in the electrochemical behavior of the Morin complexes. An isobestic point and a new spectrum band appeared indicating the formation of the new system of Morin-Cu-DNA at lambda(m)=391 nm and Morin-beta-CD-DNA at lambda(m)=375 nm. The intercalation of Morin-Cu and Morin-beta-CD complexes with DNA produces an electrochemically inactive supramolecular complex. The binding constants were calculated from the increase of the solubility, the strong hypochromism, and the decrease in peak current of Morin and its complexes upon the addition of the host molecules. Calculation of the thermodynamic parameters of the interaction of the inclusion complex of Morin-beta-CD with DNA, including Gibbs free energy change, Helmholz free energy and entropy change shows that the complexation is a spontaneous process of association.

Ursodeoxycholic acid in neonatal hepatitis and infantile paucity of intrahepatic bile ducts: review of a historical cohort.

We retrospectively reviewed the role of ursodeoxycholic acid in infants having nonsurgical cholestasis attending the Hepatology Clinic, New Children Hospital, Cairo University, Egypt, from 1985 until 2005. Files of 496 infants with neonatal hepatitis and 97 with intrahepatic bile duct paucity were included; of them 241 (48.6%) and 52 (46.4%) received 20-40 mg/kg/day ursodeoxycholic acid for 319.2 +/- 506.9 days and 480.3 +/- 583.3 days, respectively. The outcome of infants with neonatal hepatitis with intake of ursodeoxycholic acid and those without was: 108 (44.8%) and 179 (70.2%) successful (P = 0.000), 11 (4.6%) and 13 (5.1%) improved (P = 0. 474), 112 (46.5%) and 61 (23.9%) suffered failed outcome (P = 0.000), and 10 (4.1%) and 2 (0.78%) died (P = 0.014), respectively. Likelihood of successful outcome with ursodeoxycholic acid intake was 0.345 (P = 0.000), and that of deterioration was 2.76 (P = 0.000). For those having intrahepatic bile duct paucity likelihood of successful outcome with ursodeoxycholic acid intake was 0.418 (P = 0.040) and that of deterioration was 2.64 (P = 0.028). Ursodeoxycholic acid failed in management of this cohort of infants with nonsurgical cholestasis.

Clinical and microbiological efficacy of MDT in the treatment of diabetic foot ulcers.

OBJECTIVE: To assess the clinical and microbiological efficacy of maggot debridement therapy (MDT) in the management of diabetic foot ulcers unresponsive to conventional treatment and surgical intervention. METHOD: Consecutive diabetic patients with foot wounds presenting at the vascular surgery unit and the diabetic foot unit of Alexandria Main University Hospital were selected for MDT. Lucilia sericata medicinal maggots were applied to the ulcers for three days per week. Changes in the percentage of necrotic tissue and ulcer surface area were recorded each week over the 12-week follow-up period. Semiquantitative swab technique was used to determine the bacterial load before and after MDT. RESULTS: The sample comprised 10 patients with 13 diabetic foot ulcers. The mean baseline ulcer surface area was 23.5cm2 (range 1.3-63.1), and the mean percentage of necrotic tissue was 74.9% (range 29.9-100). Complete debridement was achieved in all ulcers in a mean of 1.9 weeks (range 1-4). Five ulcers (38.5%) were completely debrided with one three-day MDT cycle. The mean reduction in ulcer size was significant at 90.2%, and this occurred in a mean of 8.1 weeks (range 2-12). The mean weekly reduction in ulcer size was 16.1% (range 8.3-50). Full wound healing occurred in 11 ulcers (84.6%) within a mean of 7.3 weeks (range 2-10). The bacterial load of all ulcers reduced sharply after the first MDT cycle to below the 10(5) threshold, which facilitates healing. CONCLUSION: The results highlight the potential benefits of MDT in diabetic wound care in developing countries. MDT was proved to be a rapid, simple and efficient method of treating these ulcers.

Susceptibility to severe Streptococcal sepsis: use of a large set of isogenic mouse lines to study genetic and environmental factors.

Variation in responses to pathogens is influenced by exposure history, environment and the host's genetic status. We recently demonstrated that human leukocyte antigen class II allelic differences are a major determinant of the severity of invasive group A streptococcal (GAS) sepsis in humans. While in-depth controlled molecular studies on populations of genetically well-characterized humans are not feasible, it is now possible to exploit genetically diverse panels of recombinant inbred BXD mice to define genetic and environmental risk factors. Our goal in this study was to standardize the model and identify genetic and nongenetic covariates influencing invasive infection outcomes. Despite having common ancestors, the various BXD strains (n strains=33, n individuals=445) showed marked differences in survival. Mice from all strains developed bacteremia but exhibited considerable differences in disease severity, bacterial dissemination and mortality rates. Bacteremia and survival showed the expected negative correlation. Among nongenetic factors, age -- but not sex or weight -- was a significant predictor of survival (P=0.0005). To minimize nongenetic variability, we limited further analyses to mice aged 40-120 days and calculated a corrected relative survival index that reflects the number of days an animal survived post-infection normalized to all significant covariates. Genetic background (strain) was the most significant factor determining susceptibility (P< or =0.0001), thus underscoring the strong effect of host genetic variation in determining susceptibility to severe GAS sepsis. This model offers powerful unbiased forward genetics to map specific quantitative trait loci and networks of pathways modulating the severity of GAS sepsis.

Post-portoenterostomy triangular cord sign prognostic value in biliary atresia: a prospective study.

The triangular cord sign (TC sign) is a sensitive and specific tool in prompt diagnosis of extrahepatic biliary atresia. The objective of this study is to evaluate post-operative TC sign presence in outcome prediction of infants with biliary atresia after Kasai hepato-portoenterostomy 27 infants and children with biliary atresia underwent 122 ultrasound examinations using both 5 MHz and 7 MHz convex linear transducers in 33 months follow up. For all infants TC sign identification was included pre-operatively, ultrasound was done 2 weeks post-operatively then bimonthly for 3 months, monthly for 2 months and every 3 months thereafter. 14 (53.8%) had post-operative TC sign. Once post-operatively positive, it remained positive throughout the study. It did not reappear in an initially post-operatively TC sign negative infant. Those having post-operative TC sign had statistically worse outcomes (0 became anicteric, 2 improved, 7 had progressive disease and 6 died) than those with a negative TC sign (p = 0.04) (3 became anicteric, 5 improved, 2 progressed and 1 died). Presence of TC sign post-operatively correlated with measure of removal of all fibrous cone at porta-hepatis during portoenterostomy (p = 0.026). Post-portoenterostomy TC sign is associated with more morbidity and mortality; and reflects inadequate surgical technique.

Examination of the molecular signature associated with islet dysfunction.

The aim of this study was to identify the molecular signatures that are predictive of nonfunctional islet preparations. We examined functional outcomes of six islet preparations accepted for research purposes from human donors. Islet were maintained on culture in M-SFM media for 7 to 14 days then transplanted into NOD-SCID mice. At the time of transplant, RNA was extracted from a second aliquot of cultured islets for expression analysis. We also performed gene expression analysis using high-density Affymetrix U133A GeneChips on these preparations. Among 1833 genes selected, hierarchical clustering was performed using the GeneSpring software package (Silicon Genetics, Inc.), where 754 genes (higher in nonfunctional) and 177 genes (lower in nonfunctional) were differentially expressed with tight pattern of expression. Islets with low functionality showed high relative levels of expression of hypoxia-induced genes and increased frequency of expression of proinflammatory and proangiogenic genes, such as vascular endothelial growth factor. Conversely, nonfunctional islets had low levels of insulin-processing message. The general profile of these low-functionality islets shows attempted recovery from hypoxic assault and little effort directed toward insulin production and secretion. Further identification of the molecular signature of nonfunctional islets could allow the development of a potency assay for human transplantation.

Hepatitis C virus infection in Egyptian children: single centre experience.

The outcome of hepatitis C virus (HCV) infection acquired in childhood is uncertain because of the diversity of the epidemiological and clinical features of infection and disease. The aim of this study was to determine the outcome of HCV infection in 105 Egyptian children who tested positive for HCV antibody (anti-HCV). The data of 105 anti-HCV-positive children presenting to the Pediatric Hepatology Unit, Cairo University Children's Hospital, between 1995 and 2002, were retrospectively analysed for risk factors. Seventy-four children with available polymerase chain reaction results were further analysed clinically, serologically and histologically. The age range was 1.3-22 years, with a mean of 11.2 +/- 4.9 years. History of blood transfusion was found in 81 children (77%). HCV RNA was detected in 58.1% of 74 children. Persistently elevated alanine aminotransferase (ALT) levels were present in 40 patients (54.1%). Hepatitis B virus markers (HBsAg and/or anti-HBc) were detected in 18 patients (24.3%). Twenty-six of the 43 HCV RNA-positive children underwent a diagnostic liver biopsy that showed chronic hepatitis in 19 patients (73.1%), cirrhosis in one case only (3.8%), and normal biopsy findings in seven children (26.9%). Blood transfusion remains a major risk of HCV transmission among Egyptian children. HCV infection is not always benign in the childhood period. ALT levels remain elevated in half of the children and histological abnormalities are detected in three quarters of HCV RNA-positive cases.

Adenovirus-based vascular endothelial growth factor gene delivery to human pancreatic islets.

Islet transplantation is limited by islet graft failure due to poor revascularization, host immune rejection and nonspecific inflammatory response. Delivery of human vascular endothelial growth factor (hVEGF) gene to the islets is likely to promote islet revascularization and survival. We used a bicistronic adenoviral vector encoding hVEGF and CpG-free allele of green fluorescent protein (Adv-GFP-hVEGF) and introduced into human pancreatic islets by transfection. We found that transfection efficiency and apoptosis were dependent on the multiplicity of infection (MOI). Compared to Adv-GFP transfected and nontransfected islets, the levels of hVEGF secreted from Adv-GFP-hVEGF transfected islets were higher and exhibit a linear relationship between hVEGF expression and MOI (10-5000). Persistent, but low level expression of hVEGF from nontransfected islets was also observed. This may be due to expression of the endogenous hVEGF gene under hypoxic conditions. The levels of DNA fragmentation determined by ELISA of islet lysates were dependent on the MOI of Adv-GFP-hVEGF. On glucose challenge, insulin release from transfected islets was comparable to nontransfected islets. Immunohistochemical staining for hVEGF was very high in Adv-GFP-hVEGF transfected islets. Weak staining was also observed for hCD31 in both transfected and nontransfected islets. These findings suggest that Adv-GFP-hVEGF is a potential candidate for promoting islet revascularization.

Human islet graft function in NOD-SCID mice predicts clinical response in islet transplant recipients.

The purpose of this study was to evaluate the utility of nondiabetic immune-deficient NOD-SCID mouse model in assessing the functional capacity of isolated human islets. We transplanted 2000 islet equivalents obtained from six preparations used for human islet transplantation in three patients under the kidney capsule of groups of 10 mice. Human (Hu) C-peptide and insulin levels were determined following intraperitoneal (i.p.) glucose challenge at days 0, 7, 14, 21, 30, 60, 90, and 120. The Hu C-peptide level >1.5 ng/mL was the threshold for islet function in this model. The first patient did not achieve insulin independence and had minimal (0.5 ng/mL) fasting C-peptide levels that mirrored the low C-peptide levels observed in the mice. After the first infusion, the insulin requirements were reduced by 50% in the second patient. She became insulin free 10 days after her second infusion with a C-peptide level of 3.0 ng/mL, which corresponded to the peak C-peptide level (3.9 ng/mL) observed in the mice. By 150 days' posttransplant, the decline in C-peptide level paralleled the decline observed in mice. Within 2 weeks after the first transplant, insulin dose was reduced by 75% in the third patient, which corresponded to the robust C-peptide production in mice (7.3 ng/mL). Both patient and mice had a delay in islet function following the second infusion. She remained with a C-peptide level of 1.8 ng/mL and insulin free until suffering a rejection episode 3 months later. We observed that human islet graft function in NOD-SCID mice correlated with clinical response in islet transplant recipients.