686 research outputs found
Interlaced Influence of Various Water Quantities and Mite Densities on Broccoli (Brassica Oleracea.) Production
This study was carried out at Faculty of Agricultural- Suez Canal University which located in north eastern Egypt, within the Governorate of Ismailia. The experiment was conducted to assess the influence of different amounts of water and mite densities (phytophagous & predaceous ) on Broccoli production. Thus; the factor of water amounts comprise into three treatments (Q1, Q2 and control ) with average (977.63, 1955.28 and 2371.5 m3/fed.) respectively during period December 2014 to April 2015. The results revealed that The water quantities have a significant influence on Phytophagous and Predacieous mites where the highest mean value for mites density was observed with ( Q2 ) by (10.5N/in2) and (8.16 N/in2) for Phytophagous and Predacieous mites respectively. On the other hand; the density of Phytophagous mite by ( 1 n/in2) need approximately 167.12, 134.18 and 154.82 heat units under treatment Q1, Q2 and C respectively. However; Predacieous mite density (1n/in2) needs for 269.38 heat units under Q1 and 172.23 heat units under both Q2 and C treatments. Furthermore; the value of yield under treatment Q2 was the highest value (9.017 ton / fed) comparing with others treatmentâs values (7.91 & 5.04 ton/fed) for (Q1 and Control respectively). However; with treatment Q1 recorded a highest Irrigation water use efficiency ( IWUE ) by (7.96 Kg/m3) after obtaining Heat use efficiency (HUE) 5.5 heat unit. Thus; from previous data analysis that best treatment is Q1 (low amount of water) which gain a good value both (IWUE) and (HUE). Keywords: water quantities; mite densities; Irrigation water use efficiency and broccoli production
Adsorption of Mn (II) ion on polyvinyl alcohol/chitosan dry blending from aqueous solution
AbstractThe present study explored the ability of polyvinyl alcohol/chitosan (PVA/CS) binary dry blend as an adsorbent for removal of Mn (II) ion from aqueous solution. We will study how the solid-state shear ball milling is employed to prepare the polyvinyl alcohol/chitosan hydrogel crosslinked without using the crosslinking agent. The PVA/CS was characterized by LDS, X-ray diffraction, FTIR and SEM. The results revealed that during the process of ball milling at ambient temperature, a PVA/CS blending can be effectively pulverized resulting in crosslinking of PVA/CS hydrogel having nanosized particles. Also, the removal of Mn (II) ion has been found to be pH, adsorbent dosage and contact time dependent and the optimum pH was 6.0. From the testing of equilibrium data by Langmuir and Freundlich isotherm models, it was found that the adsorption equilibrium was fitted well by Freundlich isotherm model. In addition, the kinetic adsorption was fitted well by the pseudo-second-order kinetic model. The thermodynamic study indicated that the adsorption of Mn (II) ion onto PVA/CS was spontaneous and endothermic in nature. Also, it showed that the PVA/CS binary blend was a good adsorbent for the removal of Mn (II) ion from aqueous solution
Biometrics of Aquatic Animals
This chapter is a part of the book âRecent advances in biometricsâ introduces the importance of biometrics in the aquatic studies in brief view. Biometric measurements (Morphometric, meristics and description) are widely used in various fieldsâ âtaxonomy, species identifications, monitoring of pollution, species abnormalities, comparison, environmental changes, growth variation, feeding behavior, ecological strategies, stock management, and water quality of aquaculture. These data were collected from several articles and books of aquatic animals and presented both applications and required considerations for biometric implementations. It is important also to detect sexual dimorphism, adaptations during evolutionary time and diminishing intraspecific competition by increasing niche portioning. The biometrics could be applied for various aquatic organisms as dolphins, sharks, rays, mollusca, crustaceans, protozoa, ⊠etc. and for specific organs like teeth, otolith and appendages by different techniques and preservations. Scientists are still applying these measurements even with the presence of advanced techniques like PCR as they are low in cost, faster and more applicable. This chapter also presented some recent trends including animalâs biometric recognition systems, followed by challenges and considerations for the biometrics implementations. It is recommended to apply biometrics in wide range together with modern techniques considering the specificity of its quality and preservation status
Clay minerals damage quantification in sandstone rocks using core flooding and NMR
Sandstone oil reservoirs consist of different clay minerals such as kaolinite, illite, and chlorite. These clay minerals highly affect the formation damage during enhanced oil recovery (EOR) and well stimulation operations in these reservoirs. No attention was paid to investigate the effect of these clay minerals on the formation damage during different reservoir processes. In addition, no solution was introduced to mitigate the effect of clay minerals on the formation damage in sandstone reservoirs. In this study, the effect of clay mineral contents and type on the formation damage was studied in detail by injecting water and HCl as damaging fluids. Bandera grey, Berea, and Bandera brown sandstone rocks with various clay mineral contents were studied. XRD was used to characterize the sandstone rocks to determine the clay type and content in each rock. Two core plugs from each rock were selected for HCl and water injection. Core flooding experiments were performed to measure the initial and final permeability. In the core flooding experiments, fluids were injected into the cores at 25 °C and at a backpressure of 1000 psi. SEM was carried out before and after flooding for the tested rocks to locate the change in the clay distribution inside the rocks. The NMR analysis of core samples was done before and after flooding with the damaging fluid to quantify the formation damage and to find the possible damaging mechanism. NMR was used to locate the damage inside the rock due to the migration of clay minerals. Based on the core flooding, SEM, and NMR analysis, the maximum damage by the fresh water took place in Berea sandstone core due to fine migration and clay swelling. The illite clay mineral and chlorite can cause the formation damage on HCl injection. Illite can break down and migrates in the cores during the acid injection. In sandstone acidizing, chlorite clay mineral caused iron hydroxide precipitation inside the cores during treatment with mud acid. NMR showed that clay minerals plugged the pore throats of the rocks and reduced the rock permeability during the injection of fresh water
Prevalence and antimicrobial resistance pattern of bacterial strains isolated from patients with urinary tract infection in Messalata Central Hospital, Libya
AbstractObjectivesTo investigate the prevalence of urinary tract infection among patients at Messalata Central Hospital, Libya, to identify the causative bacteria, and to explore their resistance pattern to antimicrobials.MethodsA total number of 1153 urine samples were collected from patients, who attended daily to Messalata Central Hospital, Libya, in a study extended for one year. Antimicrobial susceptibility testing and isolates typing were done using Phoenix BD (BD diagnostic). Resistance was confirmed manually using agar disk diffusion method.ResultsOf the 1153 urine samples tested, 160 (13.9%) samples were positive, from which 17 different, solely Gram negative, uropathogens were identified. Escherichia coli were the most prevalent (55.6%) bacteria, followed by Klebsiella pneumoniae subspecies pneumoniae (16.3%), Proteus mirabilis (6.3%), Pseudomonas aeruginosa (5.6%), Enterobacter cloacae and Klebsiella oxytoca (2.5%, each), Citrobacter koseri and Providencia rettgeri (1.9%, each), Acinetobacter baumannii, Enterobacter aerogenes and Proteus vulgaris (1.3%, each), and Aeromonas caviae, Citrobacter freundii, Cronobacter sakazakii, Enterobacter amnigenus biogroup 2, Pseudomonas putida and Serratia marcescens (0.6%, each). The isolated uropathogens showed increased levels of resistance ranged from 10.5% to 64.5%, with an overall resistance of 28.9%. Amikacin was the most effective antimicrobial followed by Imipenem and Meropenem (0%, 0.6% and 2.5% resistance, respectively); while, Cephalothin and Ampicillin were the least (80.6% and 90.0% resistance, respectively) effective.ConclusionsThe obtained results emphasized the emergence of highly resistant bacteria to most of tested antimicrobials and raise the alarm for physicians to change their treatment pattern depending on antimicrobial susceptibility results
Optical Sensing Properties of Dithiocarbamate-Functionalized Microspheres, Using a Polyvinylpyridine-Polyvinylbenzyl Chloride Copolymer
In this study, a new modified optical chemical sensor based on swellable polymer microspheres is developed using a 5% copolymer of polyvinylpyridine-polyvinyl-benzyl chloride microspheres functionalized as the corresponding dithiocarbamate. This sensor demonstrated significant enhancements in sensitivity, dynamic range and response time. These improvements are related to the presence of pyridine in the polymer backbone, which is believed to increase the space between the groups, thus decreasing steric hindrance, and hence increasing substitution of the dithiocarbamate group. The hydrophilicity of pyridine also allows free movement of the solvent and analyte to and from the inside of the microspheres. These dithiocarbamate-derivatized polymer microspheres were embedded in a hydrogel matrix of polyvinylalcohol cross-linked with glutaraldehyde. This sensor responded selectively to Hg2+ solutions of different concentrations (1 Ă 10â5 M to 0.1 M). The observed turbidity measured as absorbance varied between 1.05 and 1.75 units at a wavelength of 700 nm. The response is based on the interaction between the metal cations with the negative charges of the deprotonated dithiocarbamate functional group, which led to neutratization of the charges and thus to polymer shrinking. As a result, an increase in the turbidity of the sensing element due to a change in the refractive index between the hydrogel and the polymer microspheres occured. The changes in the turbidity of the sensing element were measured as absorbance using a conventional spectrophotometer
Fabrication Of Titania Nanotubes By A Modified Hydrothermal Method
The main setback of the fabrication of titania nanotubes by the hydrothermal method is the long dissolution time and the usage of highly concentrated NaOH. Our group has managed to develop a modified hydrothermal process that is capable of fabricating titania nanotubes in a shorter timespan while using a more dilute NaOH solution. The study shows that the titania nanotubes starts to form from 7 hours of dissolution, and more nanotubes is produced as the dissolution duration is extended. Similarly, we are able to produce titania nanotubes from a more dilute NaOH solution than those reported earlier. By varying the parameters of the fabrication process, different nanostructures can be obtained such as single, branched nanowires and nanobelts
Effects of dietary bakerâs yeast extract on the growth, blood indices and histology of Nile tilapia ( Oreochromis niloticus L.) fingerlings
Nile tilapia, Oreochromis niloticus (average initial weight, 5.91 ± 0.04 g), were fed four isonitrogenous and isolipidic diets for 84 days. The diets contained four levels of yeast extract (CWâI) rich in nucleotides and ÎČâglucan: 0 (control), 5, 10 and 15 g/kg diet. Weight gain increased linearly, whereas the feed conversion ratio decreased linearly with increasing levels of yeast extract. The diet containing 15 g/kg yeast extract resulted in significantly better (p 0.05) differences were found in dry matter, protein, lipid or ash contents or in haematocrit, haemoglobin or total protein contents among the treatment groups. Blood sample profiles showed an increase in white and red blood cells in fish fed 15 g/kg yeast extract in comparison with the other treatment groups. The fish fed the diets with 10 and 15 g/kg yeast extract had significantly higher albumin and globulin levels than the control group, whereas decreased levels of cholesterol and triglycerides, aspartate aminotransferase and alanine aminotransferase were noted in fish fed the diet with 15 g/kg yeast extract. Histological analysis of the liver and intestine in fish fed the control diet showed a slightly abnormal structure in these organs. Only in fish fed diets supplemented with the highest amount of yeast extract was the structure of the hepatocytes and villi almost unchanged, which indicated that the yeast nucleotides could improve hepatic function and promote liver and gut restoration
Reproductive biology of greasy grouper, Epinephelus tauvina and coral hind grouper Cephalopholis miniata (Family: Serranidae) in the southern Red Sea, Shalatien, Egypt
Groupers are the main component of commercial fisheries in the Red Sea. The reproductive biology of Epinephelus tauvina and Cephalopholis miniata collected at the Shalatien landing site in the southern Egyptian Red Sea were investigated from January to December 2017. A total of 212 specimens of E. tauvina with a total length range of 23.6 to 70.3 cm and 243 specimens of C. miniata with a total length range of 17.4 to 42.1 cm were examined. Females of E. tauvina and C. miniata accounted for 61.7 and 61.9% of the total fish sampled, showing a 1:1.61 and 1:1.63 male-to-female sex ratio, respectively. The monthly distribution of maturity stages and gonadosomatic index values showed that the spawning season for both sexes was extended from April to October for E. tauvina and from April to September for C. miniata. The lengths at first sexual maturity of the males and females of E. tauvina were estimated at 49 and 48.1 cm, respectively, while those for C. miniata were estimated at 23.2 and 22.7 cm, respectively. All our results can help in the proper management of these valuable resources
Extracorporeal shock wave lithotripsy (ESWL) versus flexible ureteroscopy (F-URS) for management of renal stone burden less than 2 cm in children: A randomized comparative study
Objective: To compare the outcome of flexible ureteroscopy (F-URS) versus extracorporeal shock wave lithotripsy (ESWL) for the management of renal stone burden less than 2 cm in children.Patients and methods: A randomized comparative study was conducted at our hospital between December 2013 and May 2015. Seventy two children with renal stone burden less than 2 cm were assessed for eligibility. Our primary outcome is to assess the stone free rate after the first session. The secondary goal is to assess the operative outcome and the associated postoperative complications.Results: Finally, 57 children were completed the treatment and follow up; 27 patients in F-URS group and 30 patients in ESWL group. Patientâs demographics and stone characteristics were comparable between both groups. F-URS group was associated with significantly longer operative time and hospital stay versus ESWL group. Overall complications occurred in 29.6% and 33.3% in F-URS groups and ESWL group, respectively (p value = 0.1) and most of them were of minor degree. F-URS was associated with significantly higher stone free rate after the first session which reached 81.4% versus 53.3% for ESWL group (p value = 0.00). The overall success was 92.5% and 90% in F-URS and ESWL group, respectively (p value = 0.5).Conclusion: Stone free rate after one session of F-URS is higher than ESWL with comparable rates of complications. F-URS could be offered to children who are less likely to respond completely after ESWL monotherapy.Keywords: Pediatric urolithiasis; Minimal invasive stone management; Flexible URS; ESW
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