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The production of the amino polysaccharide (chitosan) from crustacean sources has faced many hindrances due to environmental, seasonal and noneconomic issues. On the other hand, mycogenic chitosan has many advantages that make it suitable for many medical and nutritional applications over the non-mycological counterparts. A number of fungal isolates have been screened for chitosan production, where the most potent fungal isolate has been genetically identified using 18S rDNA and selected to be the focus of the current study. The factors affecting chitosan production by the selected fungal isolate have been studied and numerically optimized and validated using Box–Behnken design. The produced chitosan has been collected, purified and characterized for the degree of deacetylation (DDA), molecular weight (MW), water-binding (WBC) and fat-binding capacities (FBC). Results showed that Aspergillus terreus (F3) was the most potent chitosan-producing fungal isolate with maximum validated productivity (2.92 g/l) at the following conditions: glucose, 35.6 g/l; (NH4)2SO4, 4.6 g/l; CaCl2, 0.29 g/l; and pH 7.9 at 23.2 °C for 10 days. The purified chitosan has the following characteristics: 71.9%, DDA; 54.1165 KD, MW; 58.6%, WBC; and 47.6%, FBC. The features and applications of fungal chitosan are not fully uncovered which necessitates further studies.

Femoral head chondroblastoma poses a surgical challenge. Anatomical limitations may lead to increased risk of local recurrence, damage to the articular cartilage, growth disturbances, and/or avascular necrosis (AVN). We are presenting our results with surgical hip dislocation approach with the aim to evaluate its efficacy in preventing recurrence and its safety, preserving a functional hip joint and avoiding complications. Ten patients were managed using surgical hip dislocation with direct access to femoral head lesions, extended curettage through a modified trapdoor approach, and cement reconstruction. These were six males and four females, with a mean age of 17 ± 2.7 years (range: 14–20) and a mean follow-up of 34 ± 12 months (range: 17–57). The lesion extended into the neck in 60% of patients with the physis being either closed in seven or closing in three patients. We had a single case (10%) of recurrence at the trochanters for which re-curettage was done. However, all patients had their hips preserved with good function at the latest follow-up, and no serious complications recorded. The Musculoskeletal Tumor Society score improved significantly from a pre-operative median of 23.5 (range: 16–28) to a post-operative median of 29 (range: 26–30) (P = 0.005). This report describes a safe reproducible approach to effectively manage these locally aggressive lesions with good short-term results. This is done while maintaining the integrity of the articular surface, growth plate, as well as preserving the femoral head blood supply.

Gold nanoparticles (AuNPs) have different unique properties and a wide range of applications in different fields. Thereby, there is a growing urgency for the production of AuNPs using a safe and an economic method. In this study, optimization of fermentation conditions by Bacillus subtilis NRC1 for extracellular AuNPs synthesis using response surface methodology was achieved. The data obtained from Plackett–Burman design followed by Box–Behnken design indicated the accuracy and reliability of the model and it could be used to navigate the design space with a reasonable accuracy. Numerical optimization of Bacillus subtilis NRC1 active extracellular filtrate production, showed the optimum conditions of 0.74% (w/v) casein hydrolysate, 3.99% (w/v) dextrin, 47 × 106 CFU/ml inoculum size at pH 7.76 and 25 $$^\circ$$ ∘ C to give the maximum AuNPs biosynthesis. The model was highly valid and the obtained data had a confidence factor of 98.48%. Statistical optimization resulted in a 2.6-fold increase in AuNPs production compared with that of the non-optimized medium.

Fractures of the posterior wall (PW) of the acetabulum have a wide variety of patterns; treating them as a single entity using the standard ilio-ischial plate would be inappropriate. We are presenting our experience with a fragment-specific fixation technique in which each PW fragment is reduced and fixed with separate buttress/anti-glide plate(s) in a tailored fashion, abandoning the use of the ilio-ischial plate. Fragment-specific fixation was applied to 46 patients with PW fractures (33 simple and 13 associated fracture types) with a mean follow-up of 34.9 ± 20.5 months (range: 12–72). Kocher-Langenbeck approach was utilized for all patients with dissection limited to the fracture site (a limited form of the approach was used in three patients). Anatomical reduction of the fracture was achieved in 41 (89.1%) patients, imperfect reduction in four (8.7%), and poor reduction in one (2.2%) patient. Excellent to good radiological and functional results were achieved in 91.3% of cases. A single case had recurrent subluxation which was related to avascular necrosis of the highly comminuted wall fragments. Four patients developed post-traumatic arthritis and required total hip arthroplasty. None of our cases developed clinically significant heterotopic bone formation. With a versatile yet a strong-enough construct and limited soft tissue dissection, fragment-specific fixation yielded very good results with few complications.

Heba Nassar,1 Ahmed Hasanin,1 Mahmoud Sewilam,1 Heba Ahmed,1 Mohamed Abo-Elsoud,2 Omar Taalab,2 Ashraf Rady,1 Heba Allah Zoheir1 1Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, Cairo, Egypt; 2Department of Orthopedic Surgery, Cairo University, Cairo, EgyptCorrespondence: Ahmed HasaninDepartment of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, EgyptTel +20 109 507 6954Email ahmedmohamedhasanin@gmail.comBackground: This study aimed to investigate the analgesic efficacy and motor block profile of single-shot transmuscular quadratus lumborum block (QLB) in comparison with those of suprainguinal fascia iliaca block (FIB) in patients undergoing hip arthroplasty.Methods: This randomized, double-blinded, controlled trial included adult patients undergoing hip arthroplasty under spinal anesthesia. Patients were allocated to one of two groups according to the regional block received: FIB group (n=19) or QLB group (n=17). Both study groups were compared with regard to the duration of analgesia (primary outcome), block performance time, pain during positioning for spinal anesthesia, total morphine consumption in the first postoperative 24-h period, quadriceps muscle power, and static and dynamic visual analog scale.Results: Thirty-six patients were included in the final analysis. Both study groups had comparable durations of analgesia. Postoperative visual analog scale (static and dynamic) values were comparable between the two groups in most readings. The block performance time was shorter in the FIB group. The number of patients with pain during positioning for the subarachnoid block was lower in the QLB group. The total morphine requirement during the first 24 h was marginally lower in the FIB group, whereas the quadriceps motor grade was higher in the FIB group than in the QLB group at 4 h and 6 h after surgery.Conclusion: Both single-shot blocks, namely the suprainguinal FIB and transmuscular QLB, provide effective postoperative analgesia after hip arthroplasty. FIB showed slightly lower 24-h morphine consumption, while QLB showed better quadriceps motor power.Clinical Trial Registration: The study was registered at clinical trials registry system before enrollment of the first participant (NCT04005326; initial release date, 2 July 2019; https://clinicaltrials.gov/ct2/show/NCT04005326).Keywords: quadratus lumborum block, fascia iliaca block, hip arthroplasty

Gold nanoparticles (AuNPs) have different unique properties and a wide range of applications in different fields. Thereby, there is a growing urgency for the production of AuNPs using a safe and an economic method. In this study, optimization of fermentation conditions by Bacillus subtilis NRC1 for extracellular AuNPs synthesis using response surface methodology was achieved. The data obtained from Plackett-Burman design followed by Box-Behnken design indicated the accuracy and reliability of the model and it could be used to navigate the design space with a reasonable accuracy. Numerical optimization of Bacillus subtilis NRC1 active extracellular filtrate production, showed the optimum conditions of 0.74% (w/v) casein hydrolysate, 3.99% (w/v) dextrin, 47 × 10

Some environmental and nutritional parameters controlling the biosynthesis of α-amylase from Aspergillus flavus, F7 attacking the water hyacinth have been investigated under solid state fermentation conditions for maximum amylase production. The following optima’s were recorded for the highest α-amylase yield; Incubation period 7 days; temperature, 30oC; pH, 5; inoculum size, 3X108 spores/ml; flask volume 100 ml capacity; hyacinth fresh weight 5 g; tap water, 25 ml. Under these conditions, starch showed remarkable stimulatory effect; nitrogen sources and amino acids have no stimulatory effect. Pyridoxal hydrochloride, B6 at a concentration of 200 ppm exhibited a stimulatory effect on biosynthesis of α-amylase.

In Egypt, surface irrigation and irrigation till the tail end of the furrows or borders are commonly used with wheat (Triticum aestivum L.) and other crops, but they lead to poor aeration and ineffective use of water and fertilizers. Therefore, raised beds planting method and cut-off irrigation improve wheat productivity and raise water and fertilizer use efficiencies. A field experiment was carried out in two winter growing seasons (2017/18 and 2018/19) at Sakha Agricultural Research Station Farm, Kafr EL-sheikh Governorate. The objective was to evaluate the impact of raised bed and irrigation cut-off on growth and yield of wheat (Misr-1 variety), some water relations and the contribution of ground water table on water consumption. A split plot design was used with three replicates. The main plots were occupied by raised bed treatments: farmer's conventional flat planting method (F1), furrow 60 cm width (F2) and furrow 120 cm width (F3). The sub plots were devoted to irrigation cut-off treatments: cut-off at 100% of strip length, C100% (control), cut-off at 90% of strip length (C90%) and cut-off at 80% of strip length (C80%). The results revealed that C90% combined with F3 achieved the lowest values of seasonal applied water and water consumptive use and the highest values of water productivity (9.69 L.E m-3), water application efficiency (Ea) and grain and straw yields. On the other hand, C80% recorded the highest contribution value of ground water table (CGWT) of water consumption (21.4%), leading to increase of water saving. (with 34.05% increase)

Silver nanoparticles (AgNPs) are among the most widely biosynthesized and used nanomaterials. They have different unique properties and a wide range of applications. This study is concerned with optimization of the growth conditions of

IntroductionGlycogen storage disease III (GSD III) is an inborn error of carbohydrate metabolism that involves mainly the liver and skeletal muscles with rare potential systemic complications as osteoporosis. The aim of work of the current study was to screen children with GSD III for osteoporosis using Dual-emission-X-ray absorptiometry (DXA) scan and to measure associated parathormone (PTH) and vitamin D. Our secondary objective is to correlate between the degree of osteoporosis and the muscle state as well as the metabolic control.Material and methodsThis cross sectional study included 25 GSD III pediatric cases. The liver biochemical profile, creatine kinase (CK), vitamin D2, PTH levels were tested in addition to electromyogram (EMG), echocardiography and DXA. Twenty-five age and sex matched normal healthy controls were subjected to vitamin D2 analysis and compared to cases.ResultsThe mean ±SD age of the patients was 10.52 ± 3.1 years ranging between 5-18 years. Twenty-one patients (84%) had elevated CK levels, 14 patients (56%) had myopathy and three (12%) had sensory polyneuropathy and almost half of the patients had a mild degree of cardiac muscle hypertrophy. Ten patients (40%) had elevated PTH levels. Twenty-one patients (84%) and 96% of the controls had vitamin D2 deficiency. Thirteen patients (52%) had low BMD; two of them had osteoporosis. Patients with high CK levels significantly had low BMD (P= 0.04).ConclusionsPediatric GSD III patients have a significant prevalence of developing low BMD. It is strongly associated with myopathic changes but not significantly related to metabolic control.

Aims: To evaluate the effect of zeolite and mineral fertilizers on some soil properties, availability of soil nutrients and yield of Jew’s mallow (Corchorus olitorius) in clayey and sandy soils. Study Design: The experimental designed as split plot design with three replicates, the main plots were devoted to zeolite at the rates of 0, 4.76 and 9.52 Mg ha-1 and the sub plots were occupied by mineral fertilizers at the rates of 50% and 100% from the recommended NPK doses. Place and Duration of Study: During spring and summer seasons of 2018, the field experiments were conducted in Sakha Agricultural Research Station Farm (clayey soil) and private farm at Baltium district (sandy soil). Methodology: Jew’s mallow grains (Alexandria variety). Soil samples were collected at (0-30 cm depth) in the initial of experiment and after harvesting with the aid of soil auger at random from different parts of the experimental sites to determine the physicochemical and soil moisture characteristics of the soil. Growth characteristics (plant height and fresh mass weight) were studied. Results: The results showed that ECe, SAR and bulk density values were decreased, while CEC, total porosity, field capacity, permanent wilting point and available water values increased due to application of 9.52 Mg zeolites ha-1 when compared to untreated soil. The maximum stem height and total fresh yield of Jew’s mallow were recorded with the application of 9.52 Mg zeolite ha-1+100% NPK. Conclusion: It could be concluded that the use of zeolite in clayey and sandy soils improved the soil properties, improved the availability of soil nutrients and consequently decreased the environmental pollution. Also, the obtained results are promising for enhancing the horizontal and/or vertical expansion of agriculture in such problematic soils.

Isolation of halotolerant glutaminase producing microorganisms was carried out using medium containing different concentrations of NaCl viz. 2.9, 3.5 and 4 %. Only four fungal isolates (F1H, F2H, F3H and F4H) were able to grow at all concentrations has been selected and purified. Production of glutaminase was carried out in broth medium containing 4% NaCl. Quantitaive assay for glutaminase led to 6.43, 5.72, 6.12 and 5.86 U/ml for each isolate extracellularly, respectively. In case of intracellular production assay led to 5.2, 5.46, 5.18 and 5.77 U/ml , respectively. The isolate F1H has showed the highest productivity extracellularly and stability on subculturing so, it was chosen and selected for furthur investigations. The optimized conditions for glutaminase production by isolate F1H was found to be 6 days at 35oC and pH 7 under static and dark incbation conditions with inoculum size of 4.38x106 spores/ ml. The optimization led to production of 7.66 U/ml of enzyme with great stability at 4% salt concentration which is a good sign for probability that the enzyme could have unique properties which can be confirmed through more investigatios.The isolate was identified genetically and has shown 100% similarity to Aspergillus flavus CZCU-9 and it was given the name Aspergillus flavus CZCU-9, F1H.

Background Vitamin D deficiency increases muscle weakness and pain leading to reduced power and function, increased bone turnover and increased risk of falls and hip fractures in elderly. We postulated that vitamin D deficiency in sunny Egypt should be lower than western countries so we screen for prevalence of vitamin D deficiency among all elderly patient admitted to orthogeriatric unit by fracture hip. Results Our study showed that vitamin D deficiency is common in elderly Egyptian patients admitted to orthogeriatric unit with hip fractures. Of the study group (n 290 patients) vitamin D levels were sufficient (30 ng/dl or more) in 24 patients (8.3%) and insufficient (between 20 ng and 30 ng) in 125 patients (43.1%) and deficient (less than 20) in 141 patients (48.7%). Among the study group, female patients had lower levels of vitamin D (18.8 ± 6.9) compared to males (20.5 ± 6.7) P value 0.034. Although our study failed to link different levels of vitamin D with activity of daily life: P value was (0.116) in bathing, (0.058) in dressing, (0.115) in toileting and (054) in transfer. A little difference was found in feeding (0.036) and previous fall (0.011) and cognitive impairment; MiniCOG P value 0.017. Both previous falls and cognitive decline are in turn linked to increased fracture risk Conclusion Hypovitaminosis D is common among older patients with hip fractures even in sunny Egypt remaining slightly lower than its prevalence in western countries. Although no direct significant correlations with activity of daily life, vitamin D deficiency was associated with higher risks of previous falls and cognitive impairment both in turn increases the risk of fractures.

A novel extracellular enzyme with strong fibrinolytic activity, produced by Bacillus subtilis Egy, which was isolated from the Egyptian soil was purified and characterized. The enzyme was secreted by cultured B. subtilis Egy under solid state fermentation and purified 21.5 purification fold using precipitation by ammonium sulphate followed by ion exchange chromatography, and gel filtration on Sephadex G- 100 chromatography. Purified enzyme showed optimum activity at 50oCreaction temperature and pH 8. Enzyme stability studies revealed that the enzymeis stable up to 30 °C and it retained 80% of its activity at 40oC.In addition, the purified enzyme is stable at pH 8-9. The fibrinolytic activity was enhanced by Mn2+,Cu2+, Ca2+, Na+, and Ba2+ and inhibited by, Zn2+, and Hg2+. Moreover, the activity was decreased by EDTA and PMSF at 2 mM final concentration.

Biofuel production has attracted much attention in the last few decades. Much effort has been applied to decrease the production cost of bioethanol by using agricultural waste materials. Saccharification of lignocellulosic agricultural waste materials increases the amount of available sugars and thus reduces bioethanol production costs. Here, about 14 g/l of bioethanol (185 mg/g of dry material) was produced by Candida tropicalis Y-26 using production medium with water hyacinth hydrolysate as the sole carbon source. This hydrolysate was produced, after screening and mathematical modeling, by a combination of Aspergillus terreus F-98 and acid hydrolysis $$(\hbox {H}_{2}\hbox {SO}_{4})$$ treatments to give 409 mg/g total reducing sugars. The use of a combination of A. terreus F-98 and acid hydrolysis with $$\hbox {H}_{2}\hbox {SO}_{4}$$ , 4.66% (v/v); water hyacinth biomass, 7.56% (w/v); reaction temperature, $$119.27\,^{\circ }\hbox {C}$$ ; and reaction time, 16.11 min was optimal for the saccharification of water hyacinth.

Selenium is an essential trace element, but its oxyanions, selenite [SeO32−] or selenate [SeO42−], are ecologically toxic. Different microorganisms were reported to transform the soluble toxic selenite or selenate to the insoluble less toxic elemental selenium (Se0), forming selenium nanoparticles (SeNPs). In the present study, we isolated a selenate-reducing bacterial strain from Egyptian soil that showed remarkable tolerance for elevated sodium selenate concentration (40 mM). The treatment of the bacterial cells with 1 kGy gamma irradiation attained an extra ~10% SeNPs yield throughout 72 h. Furthermore, the irradiation improved the selenate reduction rate where almost half of the anions were reduced at the first 28 h of the incubation period, versus about 44 h by the control cells. The UV–Vis spectra of the SeNPs generated by the irradiated and non-irradiated cultures showed distinct variation. The XRD and Raman spectroscopy of the two generated nanoparticles proved the irradiation influence on the crystalline structures of the SeNPs. The FESEM, EDX, TEM, and DLS revealed that gamma irradiation has a serious impact on the size, shape, and composition of the generated SeNPs. Zeta potential showed that both generated SeNPs had negative charges but with different values, while FTIR inspection exhibited similar profiles for both types of SeNPs. Both the control and irradiated SeNPs exhibited diversified antimicrobial impact, which markedly peaked against Gram-positive test organisms with values greater than the antimicrobial test control. The cytotoxicity of the synthesized SeNPs versus the WI38 cell line and antiviral activities against adenovirus-9 were also inspected.

Egyptian soil sample was screened for isolation methioninlytic fungi by a rapid plate assay procedure. Eighteen strains of different isolated fungi were screened quantitavely for their L-methioninase activity. Chaetomium globosum was the most efficacious isolate and a dematiaceous filamentous fungi, it was identified at the molecular level by ribotyping 18S rRNA along with the biochemical characterization, and lastly completed by BLAST analysis by structure of a phylogenetic tree. Results showed that, the optimum levels of the incubation period, temperature, pH, methionine, sucrose and sodium nitrate concentrations were 3 days, 30°C, 7, 0%, 30 g/l and 1g/l, respectively. According to the produced model, at these levels, C. globosum produce L-methioninase with predicted specific activity of (≈2225 U/mg); so L-methioninase could be a good source for clinical therapeutic application. The rRNA sequence of C. globosum was deposited to gene bank under accession number KXO24450 Key words: L-methioninase, Chaetomium globosum, 18S rRNA, enzyme optimization, soil.

High-energy ball-milling in hexane medium was employed to prepare Nobel Zr-based bulk metallic glasses (BMGs) alloy of three different nominal compositions Zr47Be23Ni15Ti15, Zr50Be20Ni15Ti15 and Zr52Be18Ni15Ti15, numbers indicate at.%). The glass forming ability was found to increase with decreasing Zr and increasing Be content, which can be ascribed to the enhanced atomic size mismatch of the constituents on Be addition. Amorphous Zr47Be23Ni15Ti15 powder undergoes two-stage crystallization with onset temperatures at 640 and 700 K and glass transition temperature Tg at 566 K. In contrast, the Zr50Be20Ni15Ti15 and Zr52Be18Ni15Ti15 samples remained crystalline to a certain extent even after prolonged milling and contained FCC Zr crystallites. Structural characterization was done by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, thermal analyses were performed by means of differential scanning calorimetry (DSC) thermogram to justify the experimental findings.

The present study aims to evaluate and validate a statistical model for maximizing biosurfactant productivity by Bacillus brevis using response surface methodology. In this respect, twenty bacterial isolates were screened for biosurfactant production using hemolytic activity, oil spreading technique, and emulsification index (E24). The most potent biosurfactant-producing bacterium (B. brevis) was used for construction of the statistical response surface model. The optimum conditions for biosurfactant production by B. brevis were: 33°C incubation temperature at pH 8 for 10 days incubation period and 8.5g/L glucose concentration as a sole carbon source. The produced biosurfactant (BS) (73%) exhibited foaming activity, thermal stability in the range 30–80°C for 30min., pH stability, from 4 to 9 and antimicrobial activity against (Escherichia coli). The BS gave a good potential application as an emulsifier.

l -arginine amidinohydrolase has been reported as a powerful anticancer agent due to its mediating l -arginine starvation. The aim of this study was to screen a pool of 30 actinomycetes belonging to the species Streptomyces in order to select the potent argininolytic one. Streptomyces strains isolated from soil were firstly functional screened based on their argininolytic capacities by a qualitative assay based on a pH indicator substrate (phenol red). The second screening was the quantitative evaluation of the l -arginine amidinohydrolase activity via a Ninhydrine assay. The measurement was performed on two different cell preparations, involving the extracellular compartment and the cell lysates extract. Among the tested isolates, a strain coded as MAM5 produced extracellular and intracellular l -arginase simultaneously under the same culture conditions. The isolate was identified as Streptomyces diastaticus MAM5 by phylogenetic analysis of the 16S rRNA sequence. Optimization and validation of different process parameters via Box-Behnken design were done for maximum production of extracellular and intracellular l -arginase. Collectively, culturing in shake flasks with the optimized medium resulted in a 4.5-fold and 3.5-fold increase in extra- and intracellular l -arginase production, respectively, when compared to screening medium. Additionally, l -arginase was partially purified using heat treatment and precipitation with cold ethanol, and the enzyme exhibiting 3.2-fold and 3.1-fold for extra- and intracellular form respectively, in comparison with the crude enzyme. Both forms of l -arginase had maximum activity in alkaline pH (8.5–9) at 40–50 °C with ionic stability within pH range 8–10 and thermal stability below 60 °C.

Dense, monolithic Sn–Sb–Cu samples with a nominal composition of Sn65Sb20Cu15 were produced by standard powder metallurgical techniques with a crystallite size of approximately 100 nm. The samples have been deformed by high-temperature creep between 325 and 450 °C in steps of 25 °C under constant stress (17.5 MPa). After deformation, positron annihilation lifetime (PAL) has been studied to investigate the dynamic behavior of vacancy cluster like-nanoparticles phase in Sn65Sb20Cu15 alloy aging at room temperature (RT) in details. An irregular behavior in the PAL curves was exhibited only of T = 425 °C, and the resultant microstructures have been examined by XRD and TEM methods. The results support the idea that most positrons annihilate at structural of vacancy cluster. Electrical resistivity and enthalpy activation volume confirmed the lifetime results.

Fixation of comminuted vertically unstable sacral fractures continues to be a surgical dilemma. Although triangular osteosynthesis is a good construct and resists vertical translation, complications still occur. Herein, we introduce a new biplanar fixation technique, using segmental spinal instrumentation as an alternative to triangular osteosynthesis. This technique is remarkably valuable in cases with sacral morphology and/or complex fracture patterns that preclude safe percutaneous iliosacral screw insertion.

The optimal conditions for the production of l -methionine γ-lyase (MGL) by a soil bacterium, Streptomyces DMMMH60, were established and their effects were compared using Plackett–Burman design (PBD). Accordingly, the optimal conditions of beet molasses, yeast extract, l -methionine, MgCl2, Tween 80, initial pH, aeration, temperature, inoculum size and incubation period for the maximum MGL production (60.7 U/mg) were 23.5 g/L, 0.79 g/L, 0.87 g/L, 0.85 g/L, 0.41%, 8.3, 50 ml, 33 °C, 5.2 ml, and 4 day, respectively. Initial pH was found to be the most significant factor for the production of MGL based on the calculated percentage of participation P (%) from an analysis of the variance (ANOVA). Additionally, MGL was purified from the supernatant of S. DMMMH60 using heat treatment, DEAE-cellulose and Sephadex G100, and the purified enzyme displaying 3.15-fold in comparison with the crude enzyme. Purified enzyme exhibiting a single band of 55 kDa subunits on the SDS-PAGE and the enzyme had maximum activity in pH 8 at 45 °C with ionic stability within pH range 6.5–8.5 and thermal stability below 60 °C. In-vitro, MGL showed a significant cytotoxic effect against cancer cell lines whereas those for normal cells was demonstrated a negligible toxicity.

Apparent steady state creep of Sn 0.65 Sb 0.25 Cu 0.10 alloy is studied under different constant stresses ranging from 19.27 to 21.67 MPa near the transformation temperature ≅ 443 K . Analysis creep data in the quasi-steady state regime at 443 K reveals an anomalous creep behavior with a strain rate sensitivity parameter m changing from 0.15±0.01 to 0.33±0.01 which points to cross-slipping dislocation mechanism. The activation energy for creep deformation, Q s t , was determined to be 45.47±5.96 kJ/mole in the temperature region investigated. The experimental results obtained of Q s t are compared with those predicted by Friedel–Jaffe–Dorn and Escaig cross-slip models. The results indicated that the rate controlling dominant mechanism for creep regime is cross-slip of screw dislocations. X-ray and microstructural analysis supports that the relaxation of the internal lattice strain fields takes place during apparent steady state creep.

Biosynthesis is a multistep, enzyme-catalyzed process where simple compounds or substrates are converted or joined together to form macromolecules or more complex products. A biosynthesis process is accomplished by the action of a living microorganism. The green chemistry approach toward the synthesis of natural products by microorganisms has many advantages, such as minimally processed, large-scale production, economic viability, and health safety. Application of natural products in food, pharmacy, medicine, and agriculture fields is extensively highlighted due to their chemical stability and biocompatibility. For several decades, microorganisms have been employed in the processing of foods, feeds, and large-scale production of bio-chemicals, such as alcohol, antibiotics, antioxidants, and natural colors. Moreover, vitamins, enzymes, immunosuppressants, and hypocholesterolemic agents are also produced by microorganisms. Bacterial bioactive metabolites, specifically, are characterized with special features, such as their unique chemical structure and interaction with the environment.

The novel nanostructure of Al and Al{Fe were prepared by ball milling alumina with elemental Fe. The kinetics and nanostructure dependence of high temperature low stress Newtonian creep of Al and Al{0.3%Fe have been investigated and compared with the predications of the Nabarro{Herring (N{H) theory of directional difiusion. A simple theory based on the climb controlled generation of dislocations from a flxed density of sources is developed to explain the observed behavior. The dislocation density increases and subgrains form during the creep. Also, the presence of precipitates of FeAl3 reduces the creep rate of Al by absolute faster of 100 at the same stress and temperature, in spite of the fact that the grain size in the Al{0.3%Fe alloy is smaller by a factor of about 100 nm. The reduction of grain size to the nanometer scale improves their mechanical properties. Electron difiraction methods combined with transmission electron microscopy (TEM) and scanning electron microscopy (SEM) studies are a convenient and powerful technique for the characterization of the phases and grain structure of the resulting materials.

Graphical abstract Size distribution of tellurium nanoparticles produced by Aspergillus welwitschiae F5k., Highlights • Six fungal isolates have been screened for their ability to produce elemental tellurium nanoparticles (TeNPs). • The most promising fungal isolate was identified based on molecular basis. • The most promising fungal isolate has been used for biogenic (enzymatic) production of TeNPs. • The produced TeNPs have been characterized using DLS, TEM and FTIR. • The produced TeNPs have been evaluated for antimicrobial activity against pathogenic microorganisms., Tellurium has attracted the attention of many researchers and manufacturers due to its unique properties. Through the current work, six fungal isolates have been screened for their ability to reduce potassium tellurite (K2TeO3) into elemental tellurium nanoparticles (TeNPs). The most promising fungal isolate was identified as Aspergillus welwitschiae and given the accession number (KY766958) based on molecular basis and has been used for biogenic (enzymatic) production of TeNPs. The produced TeNPs have been characterized using DLS, TEM and FTIR. Data showed that, the particle size is 60.80 d.nm with oval to spherical shape. The produced TeNPs have been evaluated for antimicrobial activity at 25 mg/ml. Data revealed antibacterial activity against E. coli and Staphylococcus aureus (MRSA). Evaluation of the effect of γ-irradiation on TeNPs production showed that, the productivity was improved at 1 kGy and suppressed gradually at higher doses.

Polyallyl diglycol carbonate "CR-39" is widely used in etched track-type particle detectors. Doppler-broadening positron annihilation (DBPAT) provides direct information about core and valence electrons in CR-39 due to radiation effects. It provides a non-destructive and non-interfering probe having a detecting efficiency. This paper reports the effect of irradiation α-particle intensity emitted from an 241 Am (5.486 MeV) source on the line-shaped S- and W-parameters for the CR-39 samples. The behavior of the line-shaped S- and W-parameters can be related to the different phases. Modification of the CR-39 samples due to irradiation were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The XRD chart reveals a new peak that starts to appear at 2.86 MeV α-particle energy. The appearance of this peak might be related to the phase transition. The phase transition in the CR-39 polycarbonate remains complex.

The effect of irradiation dose (kGy) on a set of AlCu 8.5 samples has been studied. The samples were irradiated to doses of 10, 30, 50, 70, 100, 300, 500, 700 and 1000 kGy of 60 Co γ-source at room temperature. The effect of γ-ray irradiation on the values of the S- and W-parameters reveals two stages. In the first stage, the S-parameter increases, while the W-parameter decreases up to 70 kGy. In the second stage, the S- and W-parameters decrease and increase respectively in the dose region from 100 to 1000 kGy. The dominant controlling mechanism of the S- and W-parameters was observed.

In our previous work, the relation between grain size, enthalpy activation volume, and Cu-content in Al solid solution alloys have been presented. Also, the effect of volume fraction of the precipitate phase on the elastic modulus was assessed. The experimental results indicate an increase in the elastic modulus values, E exp, with increasing Cu-content up to ∼1 at.% followed by a monotonic decrease. At approximately 10 at.%, the modulus of the alloys drops below that of the pure Al. The average grain size has been found to depend on the Cu-content and exhibited a maximum value at 3 at.% Cu and decreased when the Cu-content was raised above this value and aged at room temperature, 100 and 580 °C, respectively. The behavior of the enthalpy activation volume, V*, in dependence of the Cu-content essentially suggests an increase in the density of obstacles of dislocation intersections.

Creep experiments were conducted on Cu –8.5 at.% Al alloy in the intermediate temperature range, 673–873 K, corresponding to 0.46–0.72 Tm, where Tmis the absolute melting temperature. The present analysis reveals the presence of two distinct deformation regions (climb and viscous glide) in the plot of log [Formula: see text] versus log σ. The implications of these results on the transition from power-law to exponential creep regime are examined. The results indicated that the rate-controlling mechanism for creep is the obstacle-controlled dislocation glide. A phenomenological model is proposed, which assumes that cell boundaries with sub-grains act as sources and obstacles to gliding dislocations.

SEM observations and Vickers hardness tests were performed to identify the irradiation effects. γ-irradiation effect during the aging hardening process can be explained depending on the composition of the alloy and is used to derive quantitative information on the kinetics of the transformation precipitates. Increasing the Cu content of an Al – Cu alloy can improve the aging hardness. The present results of the hardness behavior, with SEM observations of surveillance specimens at different doses, suggest that the radiation-induced defects are probably complex valence-solute clusters. These clusters act as nuclei for the precipitation of θ- Al 2 Cu type. This can be effectively utilized to study the systematics of nucleation of precipitates at vacancy-type defects. γ-irradiation probably plays the key role in defects responsible for material strengthening and embrittlement.

Micro-structural change caused by the corresponding change in creep properties of Cu-8.5at.%Al alloy was studied. It was found that a micro-structural observations reveal the formation of different types of defect features during creep of the investigated alloy at intermediate temperatures between 0.46-0.72Tm, where Tm is the absolute melting point. SEM was used to characterize the studied alloy by quantitative micro-analysis. It allowed the observer to defect the micro-structural features such as dislocation that were generated from deformation and could move interagranularly by glide and climb. Clearly, the development of this microstructure could be attributed to the grain refining effect of the Al indicating the role of the applied stress at this alloy. The results show that the creep rupture strength of Cu-8.5at.%Al alloy in the power law creep damage mechanism. This due to the constraint introduced on the matrix creep flow by the Al phase rather than the devolvement of high threshold stress values. While the increase in the length of Al filaments and reduction in interfilament spacing with increasing draw ratio increase the constraint on the creep flow of the matrix, they also enhance the creep damage caused by the diffusion mechanisms because of the easy diffusion paths along the Al filaments and the reduction in the matrix grain size.

Creep experiments were conducted on Cu-8.5at.% Al alloy in the intermediate temperature range from 673 to 873K, corresponding to 0.46-0.72 Tm where Tm is the absolute melting temperature. The present analysis reveals the presence of two distinct deformation regions (climb and viscous glide) in the plot of log ε vs. log σ. The implications of these results on the transition from powerlaw to exponential creep regime are examined. The results indicated that the rate controlling mechanism for creep is the obstacle-controlled dislocation glide. A phenomenological model is proposed which assumes that cell boundaries with sub-grains act as sources and obstacles to gliding dislocations.

SEM observations and Vickers hardness tests were performed to identify the irradiation effects. γ-irradiation effect during the aging hardening process can be explained depending on the composition of the alloy and is used to derive quantitative information on the kinetics of the transformation precipitates. Increasing the Cu content of an Al–Cu alloy can improve the aging hardness. The present results of the hardness behavior, with SEM observations of surveillance specimens at different doses, suggest that the radiation-induced defects are probably complex valence-solute clusters. These clusters act as nuclei for the precipitation of θ-Al2Cu type. This can be effectively utilized to study the systematics of nucleation of precipitates at vacancy-type defects. γ-irradiation probably plays the key role in defects responsible for material strengthening and embrittlement.

Background Hip fusion restricts most of daily-living activities, and patients request takedown of their fusion hoping to improve gait and function and relieve pain from adjacent joints. Patients and methods We retrospectively reviewed 27 fused hips (22 patients) converted to total hip arthroplasty between 2001 and 2013. A total of 19 male and three female patients had hip fusion for an average of 17 years (range: 6–32), with mean age at conversion of 34 years (range: 22–55). The etiology of fusion was surgical arthrodesis in seven, ankylosing spondylitis in 12, post-traumatic in four, dysplasia in two, and idiopathic in two hips. Posterolateral approach was used in all patients with intraoperative imaging to guide in-situ neck osteotomy and ensure correct positioning of the cup. A total of 18 hips were uncemented, with ceramic-on-ceramic bearing used in 11. Results Patients were followed for a mean of 96 months (range: 36–168). Center of rotation was restored to within 0.5 cm in 24 hips. Limb-length discrepancy averaging 1 cm (range: 0.5–2 cm) was noted in six patients. Harris hip score improved significantly from 46 (range: 20–56) to 78 (range: 42–97) at the last follow-up with a mean flexion range of 85° (65–120°). Abductor lurch with positive Trendelenburg sign was present in eight hips. All but two patients were satisfied with the result. One cup was aseptically loose, making for 96% implant survival. Complications also included two cases of heterotypic ossification, one partial sciatic nerve palsy that later recovered, and one hematoma formation. No dislocations or wound infections were reported. Conclusion Successful takedown of hip fusion is possible with improved function and gait and low complication rate.

The structural and electrical properties in the temperature range 76-473 K of Sbx,Se1-x (0

The optical transmission and reflection at normal incidence of amorphous Sb x Se 1− x (0⩽ x ⩽0.9) thin films of different thickness (from 40 to 320 nm) were measured at room temperature in the wavelength region 500–1300 nm. From the obtained data, the absorption coefficient α, the extinction coefficient k , refractive index n , the optical energy gap E opt g and the valence band density of states g i were computed for different values of x . These constants were found to be independent of film thickness, but depend markedly on the value of the composition x . The analysis of the absorption coefficient data revealed the existence of two optical transition mechanisms, depending on the value of x , indirect transitions for Sb x Se 1− x thin films ( x = 0.1, 0.4, 0.5, 0.7, and 0.9) and a forbidden direct transition for x = 0.3. The optical energy gap E opt g was found to vary from 0.24 eV for ( x = 0.9) to 1.92 eV for ( x = 0). It was found that the high frequency optical constants n and k increase from 3.7 to 7.4 and from 0.32 to 0.64 respectively with increasing x from 0 to 0.9.

This work presents experimental and computational simulation studies on creep deformation mechanisms of a novel nanostructured Cu and Cu -10% Sn alloy that prepared by mechanical alloying (MA) copper with elemental Tin. Mechanical Newtonian creep model is employed for computational simulation of creep deformation mechanism under low stress-high temperature and to justify the experimental findings. The observed behaviors are discussed and compared with the predications of the Nabarro–Herring (N–H) theory of directional diffusion. A simple theory based on the climb controlled generation of dislocations from a fixed density of sources is developed to explain the observed behavior. TEM and SEM investigations are convenient and powerful techniques for characterization of phases and a novel nano-grain structured of the resulting materials. The reduction of grain size to the nanometer scale improves their mechanical properties.