Efficient fracture mechanics programming system for linear and non-linear problems using finite-element and boundary-element methods

An attempt has been made, in this work, to design an efficient, linear—elastic and elasto-plastic, fracture mechanics package based upon finite and boundary element methods. The package contains many useful facilities such as, pre- and post-processors, different types of loading including inertial and thermal loading, and different types of finite and boundary elements. New crack-tip elements, and efficient algorithms for the analysis of J-integrals, have been derived. Elasto-plastic boundary element programs with different types of loading, and using a new subregion facility have also been developed. The package was employed for fracture mechanics analysis of some case studies with elastic, thermo-elastic, and elasto-plastic conditions, and with one and two modes of fracture. The results have proved that the package is very reliable and controllable, and new facilities and techniques, developed in this work, can provide useful tools for fracture mechanics analysis

Phytoremediation of Heavy Metals(Cd, Cu, Fe, and Pb) by Using Aquatic Plants in Shatt Al-Arab River

The study conducted to evaluate the ability of some aquatic plants in absorption and accumulate some heavy metals (Cd, Cu, Fe, and Pb) in their tissues from contaminated water in two sites of Shatt Al-Arab River, Province of Basrah/Iraq. Water samples were collected from two sites one of them north of Basrah (Gurna) and the other from Sindbad island middle site of Shatt Al-Arab river. The chemical analysis had been performed to find out water quality. A laboratory experiment had been conducted by using three types of aquatic plants which were; Common Hornwort (Ceratophyllum demersum L., Common Reed (Phragmites australis L, and Nut Grass (Cyperus rotundus L.). Two types of water qualities (Gurna and Sindbad island) from Shatt Al-Arab river in addition to distilled water as a control treatment. Plants were planted in glass containers filling with water samples to know the ability of plants to absorb heavy metals. Results showed that water quality, according to American salinity laboratory classification was C4S1 for both sites. Concentration of cadmium, copper, iron, and lead in Shatt Al-Arab river in both sites was (0.021, 0.034), (15.40, 23.50), (248.1, 181.0), and (15.5, 54.0) ugL-1 respectively. The preliminary analysis of heavy metals concentration in aquatic plants of Cd, Cu, Fe and Pb were 0.18, 14.5, 650.5, and 26.2 mg kg-1 of dry weight respectively. While the results were 0.45, 36.2, 1173.0, and 50.5 mg kg-1 dry weight respectively in the Ceratophyllum, Finally, in the common reed, the concentration was 0.2, 30.5, 1095.2, and 45.2 mgKg-1 dry weight for each heavy metals respectively. The removal efficiency of aquatic plants was varied with plant species and they took the following order common hornwort >common reed>nut grass

Role of three phonon scattering in the lattice thermal conductivity of an insulator : application to GaAs

Al-Edani M. C., Dubey K. S. Role of three phonon scattering in the lattice thermal conductivity of an insulator : application to GaAs. In: Bulletin de la Classe des sciences, tome 65, 1979. pp. 555-562

Culture Method and PCR for the Detection of Helicobacter pylori in Drinking Water in Basrah Governorate Iraq

Helicobacter pylori is recognized by the World Health Organization to be the primary cause of peptic ulcers, chronic gastritis, and stomach cancer, though the source of human infection is not well understood. One of the problems in understanding the source of human contamination is the difficulty in isolating the organism from the environment. However, the combination of PCR results with those of culturing of 471 drinking water samples can provide a more accurate picture of H. pylori detection. In this method 78 presumptive H. pylori colonies out of 266 tap water samples were obtained in the preliminary detection on modified Columbia agar (MCUA) slant relying on urease positivity with a rate of 29.3%. However, only 11 out of them were confirmed by Gram staining and biochemical tests reducing the rate to 4.13% whereas only 3 (1.46%) from 205 reverse osmosis (RO) water samples. Furthermore, only 6 (54.5%) out of the 11 isolates from tap water and 1 (33.3%) of the 3 RO isolates were confirmed by 16SrRNA PCR. Thus PCR confirmation reduced the rate to 2.2%. In addition, only 4 (4%) of 100 tap water samples negative for H. pylori by culture method were H. pylori positive by 16SrRNA. Water samples were collected from 24 districts of Basrah Governorate from February–December 2009. The direct recovery of H. pylori from drinking water is both alarming and scientifically exciting in terms of the investigation of its epidemiology

Efficient fracture mechanics programming system for linear and non-linear problems using finite-element and boundary-element methods

SIGLEAvailable from British Library Document Supply Centre- DSC:DX92920 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Transcriptome analysis of human cumulus cells reveals hypoxia as the main determinant of follicular senescence

STUDY QUESTION: Can RNA sequencing of human cumulus cells (CC) reveal molecular pathways involved in the physiology of reproductive aging? STUDY FINDING: Senescent but not young CC activate gene pathways associated with hypoxia and oxidative stress. WHAT IS KNOWN ALREADY: Shifts in socioeconomic norms are resulting in larger numbers of women postponing childbearing. The reproductive potential is sharply decreased with aging, and the reasons are poorly understood. Since CCs play an integral role in oocyte maturation and direct access to human oocytes is limited, we used whole transcriptome analysis of these somatic cells to gain insights into the molecular mechanisms playing a role in follicular senescence. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: Twenty CC samples (from a total of 15 patients) were obtained from oocytes of either male factor or egg donor patients. RNA sequencing and bioinformatic tools were used to identify differentially expressed genes between CCs from seven aged and eight young patients (<35 (years old) y.o. vs >40 y.o.). Quantitative-PCR and immunoflourescent staining were used for validation. MAIN RESULTS AND THE ROLE OF CHANCE: RNA sequencing identified 11 572 genes expressed in CC of both age cohorts, 45 of which were differentially expressed. In CC collected from patients >40 y.o., genes involved in the hypoxia stress response (NOS2, RORA and NR4A3), vasculature development (NR2F2, PTHLH), glycolysis (RALGAPA2 and TBC1D4) and cAMP turnover (PDE4D) were significantly overexpressed when compared with CC of patients younger than 35 y.o. LIMITATIONS, REASONS FOR CAUTION: This study focused almost exclusively on assessing the genetic differences in CC transcriptome between young and older women. These genetic findings were not fully correlated with embryonic development and clinical outcome. WIDER IMPLICATIONS OF THE FINDINGS: Our data provide a new hypothesis—follicular hypoxia—as the main mechanism leading to ovarian follicular senescence and suggest a link between cumulus cell aging and oocyte quality decay. If specific molecular findings of hypoxia would be confirmed also in oocytes, genetic platforms could screen CC for hypoxic damage and identify healthier oocytes. Protocols of ovarian stimulation in older patients could also be adjusted to diminish oocyte exposure time to hypoxic follicles. LARGE SCALE DATA: GEO accession number: GSE81579 STUDY FUNDING AND COMPETING INTEREST(S): Funded in part by EMD Serono Grant for Fertility Innovation (GFI)

Cell-free nucleic acids as non-invasive biomarkers of gynecological cancers, ovarian, endometrial and obstetric disorders and fetal aneuploidy

International audienceBackground: Proper folliculogenesis is fundamental to obtain a competent oocyte that, once fertilized, can support the acquisition of embryo developmental competence and pregnancy. MicroRNAs (miRNAs) are crucial regulators of folliculogenesis, which are expressed in the cumulus-oocyte complex and in granulosa cells and some can also be found in the bloodstream. These circulating miRNAs are intensively studied and used as diagnostic/prognostic markers of many diseases, including gynecological and pregnancy disorders. In addition, serum contains small amounts of cell-free DNA (cfDNA), presumably resulting from the release of genetic material from apoptotic/necrotic cells. The quantification of nucleic acids in serum samples could be used as a diagnostic tool for female infertility.Methods: An overview of the published literature on miRNAs, and particularly on the use of circulating miRNAs and cfDNA as non-invasive biomarkers of gynecological diseases, was performed (up to January 2014).Results: In the past decade, cell-free nucleic acids have been studied for potential use as biomarkers in many diseases, particularly in gynecological cancers, ovarian and endometrial disorders, as well as in pregnancy-related pathologies and fetal aneuploidy. The data strongly suggest that the concentration of cell-free nucleic acids in serum from IVF patients or in embryo culture medium could be related to the ovarian hormone status and embryo quality, respectively, and be used as a non-invasive biomarker of IVF outcome.Conclusions: The profiling of circulating nucleic acids, such as miRNAs and cfDNA, opens new perspectives for the diagnosis/prognosis of ovarian disorders and for the prediction of IVF outcomes, namely (embryo quality and pregnancy)