Three-dimensional Imaging of Microstructure in Gold Nanocrystals

X-ray diffraction using a coherent beam involves the mutual interference among all the extremities of small crystals. The continuous diffraction pattern so produced can be phased because it can be oversampled. We have thus obtained three-dimensional images of the interiors of Au nanocrystals that show 50 nm wide bands of contrast with f111g orientation that probably arise from internal twinning by dynamic recrystallization during their formation at high temperature

Organic matter responses to radiation under lunar conditions

Large bodies, such as the Moon, which have remained relatively unaltered for long periods of time have the potential to preserve a record of organic chemical processes from early in the history of the solar system. A record of volatiles and impactors may be preserved in buried lunar regolith layers that have been capped by protective lava flows. Of particular interest is the possible preservation of prebiotic organic materials delivered by ejected fragments of other bodies, including those originating from the surface of the early Earth. Lava flow layers would shield the underlying regolith and any carbon-bearing materials within them from most of the effects of space weathering, but the encapsulated organic materials would still be subject to irradiation before they were buried by regolith formation and capped with lava. We have performed a study to simulate the effects of solar radiation on a variety of organic materials mixed with lunar and meteorite analogue substrates. A fluence of ~3 x 1013 protons cm-2 at 4-13 MeV, intended to be representative of solar energetic particles, has little detectable effect on low molecular weight (≤C30) hydrocarbon structures that can be used to indicate biological activity (biomarkers) or the high molecular weight hydrocarbon polymer poly(styrene-co-divinylbenzene), and has little apparent effect on a selection of amino acids (≤C9). Inevitably, more lengthy durations of exposure to solar energetic particles may have more deleterious effects and rapid burial and encapsulation will always be more favourable to organic preservation. Our data indicate that biomarker compounds that may be used to infer biological activity on their parent planet can be relatively resistant to the effects of radiation, and may have a high preservation potential in paleoregolith layers on the Moon

Reconstruction of the Shapes of Gold Nanocrystals using Coherent X-ray Diffraction

Inverse problems arise frequently in physics: The magnitude of the Fourier transform of some function is measurable, but not its phase. The “phase problem” in crystallography arises because the number of discrete measurements (Bragg peak intensities) is only half the number of unknowns (electron density points in space). Sayre first proposed that oversampling of diffraction data should allow a solution, and this has recently been demonstrated. Here we report the successful phasing of an oversampled hard x-ray diffraction pattern measured from a single nanocrystal of gold

Sacrococcygeal teratoma: 10-year experience in upper Egypt

Purpose To evaluate our experience with 45 patients with sacrococcygeal teratoma (SCT) in our community (upper Egypt) over a period of 10 years between 2001 and 2011 and determine the outcome of the management and recommendations for treatment strategies.Patients and methods A retrospective study was conducted at our Pediatric Surgical Unit, Assiut University Hospital. The medical records were reviewed for age at presentation, clinical manifestations and investigations, time of surgical approach, histopathology, recurrences, bladder and anorectal function, and cosmetic outcome.Results Forty-five patients with SCT were referred to the Pediatric Surgical Unit. The time of referral was as follows: immediately after birth in the case of five patients; during the first week for 17 patients (four of them died before surgery because of hemodynamic instability and other associated congenital anomalies and were excluded from the study); later in infancy for 22 patients; and at one and half years of age for one child. The lesion was excised in the case of 41 patients. Teratomas were of type I (n =9), type II (n = 20), type III (n= 11), and type IV (n =1) (Altman’s classification). The age of patients at surgery ranged from 2 days to 1.5 years. Histological analysis of results revealed mature teratoma (n =27), immature teratoma (n =9), and malignant teratoma (n= 5). The coccyx was not removed in two cases during the early period of the study. The follow-up period ranged from 3 months to 10 years. Recurrence occurred in five (12%) cases, wound infection in four (9.7%), and diarrhea in two (4.8%) cases. The a-fetoprotein level was high in 35 cases and was normal in two patients; it decreased after excision. Fetal diagnosis was made in five cases by means of a prenatal sonographic scan.Conclusion Prenatal diagnosis of SCT is very important and it is recommended to save the baby from obstructed labor. Early diagnosis allows early surgical intervention and avoids malignant transformation. The coccyx should be excised to decrease the risk of recurrence. Skin flap modification is feasible for large teratomas with healthy skin. Keywords: infants, neonates, sacrococcygeal teratom

Transcolostomy-site endorectal pullthrough for Hirschsprung’s disease

Purpose To present our results for an endorectal pullthrough operation as the second stage for the treatment of Hirschsprung’s disease through the colostomy site.Materials and methods This study included 13 patients, four girls and nine boys. Their ages ranged from 9 months to 7 years. They presented with a leveling colostomy with a diagnosis of Hirschsprung’s disease. The colostomy was carried out in the neonatal period because of neonatal intestinal obstruction in three patients (one female and two males), in two patients because of recurrent attacks of enterocolitis, and three patients because of the inability of the patient to withstand major surgery. Four patients presented without a clear history of the cause for the colostomy. One patient aged 7 years presented with sigmoid volvulus. All the patients were subjected to a transcolostomy endorectal pullthrough.Results The operation was completed as described in all patients. The time from colostomy to pullthrough ranged from 3 to 7 months (median 4.7 months). The operation time ranged from 95 to 140 min (median 113 min). All the patients passed stool within 24–48 h. Stool output ranged from two to six stools per day. Optimal wound healing occurred in all patients without wound complications. Postoperative perineal excoriation occurred in four patients. A urinary tract infection developed in one patient. A patient with a history of recurrent attacks of preoperative enterocolitis developed mild enterocolitis 2 weeks after the operation. Adhesive intestinal obstruction occurred in one patient. Recurrence of symptoms occurred in two patients because of stricture at the anastomotic site, one responded to repeated dilatation and the other required internal sphincterotomy.Conclusion Transcolostomy endorectal pullthrough has the following advantages: it is associated with less pain and a shorter hospitalization than the classic endorectal pullthrough. Wound complications are rare. The cosmetic result is better than the classic Soave operation. It has no specific technique-related complications. Long-term outcome and functional results are good. To our knowledge, this approach has not been described before. Keywords: Hirschsprung’s disease, leveling colostomy, pullthroug

Effects of Raloxifene Hydrochloride on Bone Mineral Density and Serum Lipids in Kuwaiti Postmenopausal Women with Osteoporosis

Background: Osteoporosis is currently a major cause of mortality, morbidity, and medical expense worldwide. Aim: This study was designed to detect the effect of raloxifene hydrochloride on bone mineral density (BMD) and serum lipids in Kuwaiti postmenopausal women with osteoporosis. Subjects and Methods: Eighty postmenopausal women, who received raloxifene 60 mg with calcium 500 mg and 200 IU Vitamin D daily for 2 years were included in this prospective study which was conducted from August 2011 to August 2013 after informed consent and approval of the study by hospital ethical committee. BMD measured by dual‑energy X‑ray absorptiometry (DXA) and serum lipids were assessed before and after the treatment to detect the effect of raloxifene on BMD and on serum lipids. Unpaired t‑test was used to compare lumbar spine, total hip BMD and serum lipid values before and after the raloxifene treatment. Results: Lumbar spine and total hip BMD were significantly increased from 0.92 (3.8) and − 0.83 (5.6); respectively before treatment to 3.21 (5.4) and 1.62 (7.4); respectively 2 years after treatment. Also, Ward`s triangle and trochanter BMD were significantly increased from 1.53 (6.6) and − 1.4 (6.4); respectively to 4.84 (9.3) and 1.78 (8.5); respectively. Total cholesterol and low‑density lipoprotein cholesterol were significantly decreased from 5.15 (4.5) and 3.82 (4.6) mmol/L; respectively before treatment to 3.57 (3.4) and 2.56 (3.7) mmol/L; respectively 2 years after treatment. While, changes in high‑density lipoprotein cholesterol and triglycerides after treatment were statistically insignificant. Conclusions: Raloxifene appears to be an effective, well tolerated option for treating osteoporosis in Kuwaiti postmenopausal women, suitable for long term use with favorable effect on serum lipid profiles.Keywords: Bone mineral density, lipid metabolism, osteoporosis, postmenopausal, raloxifen

Bioleaching of metal ions from low grade sulphide ore: Process optimization by using orthogonal experimental array design

The present work was aimed at studying the bioleachability of metal ions from low grade sulphide ore containing high amount of carbonaceous materials by selected moderately thermophilic strain of acidophilic chemolothotrophic bacteria, Sulfobacilllus thermosulfidooxidans. The bioleaching process was optimized by constructing L25 Taguchi orthogonal experimental array design and optimization of variable proportions of process parameters. Five factors were investigated and twenty five batchbioleaching tests were run under lower, medium and higher levels of these factors. The parameters considered for shake flask leaching experiments were initial pH (1.8, 2, 2.5, 3, 3.5), particle size, (50, 100, 120, 200, 270 m), pulp density (1, 5, 10, 15, 25%), temperature (40, 45, 47, 52, 57oC) and agitation (100, 120, 180, 220, 280 rpm). Statistical analysis (ANOVA) was also employed to determine significant relationship between experimental conditions and yield levels. The experimental results for selective leaching showed that under engineered leaching conditions; pH 1.8, particle size 120 m, pulp density 10%, temperature 47°C and agitation 180 rpm, the percent bioleachabilities of metals were Zn 72%, Co68%, Cu 78%, Ni 81% and Fe 70% with an inoculum size of 1.0 ×107 /mL

Isolation and screening of alkaline protease producing bacteria and physio-chemical characterization of the enzyme

Soil samples from different habitats including tanneries, soap industries, garden soil and soil compost were screened for the presence of alkalophilic Bacillus isolates capable of producing alkaline protease in large quantities. One hundred and eighteen (118) isolates were found having proteolytic activity on skim milk agar plates. Isolates forming larger zones, as a result of casein hydrolysis were further studied for quantitative production of extracellular alkaline protease activity in the shake flask studies. Isolate CEMB10370 gave maximum activity. Time course studies indicated that strain CEMB10370 had the highest protease activity (380 APU/mL) after 48 h of fermentation. The wild type enzyme was biochemically characterized. The enzyme exhibits optimal activity at 50°C and pH 11.5. The protease enzyme was completely inhibited by phenylmethylsulfonyl (PMSF, serine protease inhibitor) and its isoelectric point was ~9.5. The enzyme was purified by ion-exchange chromatography using CMSepharose column as a ~29 Kilo Dalton (kDa) protein.Key words: Alkaline protease, alkalophilic ,Bacillus subtili

Antibacterial and haematological activity of Moringa oleifera aqueous seed extract in Wistar albino rats

The phytochemical, antibacterial and haematologic activity of aqueous seed extract of Moringa oleifera (Moringaceae) were evaluated. Phytochemicals such as tannins, carbohydrates, alkaloids, cardiac  glycosides, anthraquinones and flavonoids in low, moderate and high concentrations were present in the seeds. The extract exhibited significant In vitro antibacterial and In vivo haematologic effects. Bacterial isolates such as Staphylococcus aureus, Streptococcus pyogenes, Bacillus subtilis, Corynebacterium pyogenes, Klebsiella pneumoniae, Salmonella typhi, Escherichia coli and Pseudomonas aeroginosa were inhibited. The  minimum inhibitory concentration of the extract for all the sensitive isolates is 100 mg/ml and 50 mg/ml as minimum bactericidal  concentration of the extract on Staphylococcus aureus, Salmonella typhi and Escherichia coli. The extract administered per os at 100-400 mg / kg body weight significantly (P<0.05) increased, neutrophil, eosinophil, basophil and monocytes counts at second and third week of administration except for lymphocyte that significantly (P<0.05) decreased throughout the period of administration when compared to the rats in control group. The study supports the folkloric application of Moringa oleifera seed extract in the management of various forms of bacterial infection, anaemia and immuno – modulation in north eastern Nigeria.Keywords: Antibacterial effect, Haematology, Moringa olifera, Phytochemical analysis, Wistar albino rats

Parent formulation at the Lagrangian level

The recently proposed first-order parent formalism at the level of equations of motion is specialized to the case of Lagrangian systems. It is shown that for diffeomorphism-invariant theories the parent formulation takes the form of an AKSZ-type sigma model. The proposed formulation can be also seen as a Lagrangian version of the BV-BRST extension of the Vasiliev unfolded approach. We also discuss its possible interpretation as a multidimensional generalization of the Hamiltonian BFV--BRST formalism. The general construction is illustrated by examples of (parametrized) mechanics, relativistic particle, Yang--Mills theory, and gravity.Comment: 26 pages, discussion of the truncation extended, typos corrected, references adde