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Hydrocarbon production and development of carbonate reservoirs mainly depend on fractures that cross wells. Therefore, quantification of their characteristics has a crucial role in reservoir management. In this research, bedding planes, faults and different types of fractures of a Cenomanian-Turonian carbonate reservoir in the Persian Gulf were studied. Image logs including the oil-based mud image (OBMI) and the ultrasonic borehole image (UBI) were used. The results from conventional petrophysical log suites were compared to the image logs results. Based on the image logs, structural characteristics of bedding planes were reconstructed by estimating their strike, dip, dip direction and layer thickness. Fracture types and their distribution and the geometry in the well were determined. Also, fault zone geometry and type of faults were evaluated. The results indicate that majority of the bedding planes have a N58W strike with an average dip of 18° towards NE. Furthermore, both tensile and shear fractures were distinguished, although shear fractures dominated and the 328/36SW and 29/45NW were found to be the prevalent orientation of fractures. Based on petrophysical logs analyses, four facies groups are distinguished and two statistical relationships are proposed for estimation of discontinuities. The proposed index for evaluation of fractures using petrophysical logs shows good performance and it could be used for wells when no image log is available. Especially in offshore reservoirs, lack of outcrop and unavailability of image logs of old wells lead to unknown fractures characteristics which will be addressed by the suggested equations. • Based on petrophysical logs, the studied oilfield is comprised from four electrofacies. • UBI and OBMI image logs are proposed to detect open fractures and bedding plane, respectively. • Strikes NW–SE and dips to the SW (328/36) were measured as dominant geometry of the open fractures. • A new parameter called cumulative differences was proposed based on petrophysical logs to predict discontinuities. [ABSTRACT FROM AUTHOR]

The large-deformation three-dimensional glass–rubber constitutive model for isotropic, amorphous, linear polymers near the glass transition, previously proposed, has been extended to include a spectrum of network relaxations. In addition, an experimental programme of uniaxial tension and compression tests was carried out on high molecular weight cast sheets of poly(methyl methacrylate) (PMMA), with varying strain-rate and temperature across the range from 114 to 190 °C, encompassing the thermoforming range of practical importance. The extended model was found to fit successfully the data for PMMA, provided a doublet network relaxation spectrum was employed. The original model, with only a single network relaxation, was found to be grossly inadequate when there was significant network relaxation by entanglement slippage. Parameters of the model for PMMA, obtained by fitting to the new data, were compared with values obtained by other routes. [Copyright &y& Elsevier]

Background: Background: Resistance to macrolide can be mediated by erm and msrA genes in Staphylococcus aureus. There are the evidences that show erm genes may be causative agent of inducible or constitutive resistance. D-test as a simple phenotypic test can differentiate between S. aureus isolates with inducible clindamycin resistance. The aim of this study was to investigate the incidence of inducible clindamycin resistance and determine the most frequency of erm and msrA genes among S. aureus isolates. Methods & Materials: In this study a total of 124 non duplicate isolates of S. aureus collected from different clinical specimens were tested with disk diffusion method. All of isolates were tested by PCR for mecA, ermA, ermB, ermC and msrA genes. Results: According to PCR results 48.4% had mecA gene and 51.6% were mecA negative. By phenotypic D-test method, 32.3% revealed inducible resistance and recorded as D and D+. Sensitive and constitutive phenotypes were found in 54.8% and 12.9% of isolates respectively. Inducible clindamycin resistance was more prevalent in MRSA (29%) than MSSA isolates (2.4%). Among studied ermgenes, the most frequency genes were ermA and ermC with 41.1% and 17.7% respectively. Three isolates of them had D phenotype, while the PCR results of erm genes were negative. All isolates were negative for ermB or msrA genes. Conclusion: Since S. aureus isolates with inducible resistance maymutate and change to constitutive resistance, so for prevention of treatment failure, we suggest that inducible resistance test be performed in the isolates which are resistant to erythromycin and sensitive to clindamycin. [ABSTRACT FROM AUTHOR]

The long-lived plasma cells, which develop after alloantigen sensitization, produce donor specific alloantibodies (DSAs) that generate a positive serum cross-match and preclude transplantation. Bortezomib, a proteasome inhibitor, is being investigated in clinical desensitization protocols, however preclinical studies in a transplant model are nonexistent. We hypothesized that sustained treatment with only a proteasome inhibitor would eliminate plasma cells and reduce DSA over time. Cardiac allografts were transplanted into murine recipients. Eight weeks after allograft rejection the proteasome inhibitor, bortezomib, was injected intravenously twice weekly for 60 days. Serum alloantibody responses were assayed using flow cross-match. Total and alloreactive plasma cell numbers were enumerated using flow cytom-etry and EL1SP0T. All recipients of cardiac allografts rejected their graft promptly within 16 days and demonstrated alloantibody by flow cross-match. DSA was sustained in the control mice while mice treated with bortezomib had sustained elimination of DSA and a marked reduction in plasma cell population. Also, bortezomib was associated with an increased level of BLyS. Within a murine model, proteasome inhibition can eliminate alloantibody secreting plasma cells, and reduce alloantibody. Cessation of bortezomib is not associated with return of DSA. [ABSTRACT FROM AUTHOR]

A novel modified glassy carbon electrode with holmium fluoride (HoF3) nanoparticles (HoFNPs)-multiwalled carbon nanotubes (MWCNTs) is fabricated and then successfully used for the sensitive and selective determination of uric acid (UA) in the presence of ascorbic acid (AA) and dopamine (DA). HoFNPs are successfully attached on the multi-walled carbon nanotubes (MWCNTs) via the intermediate of noncovalent hydrophobic interactions of the MWCNTs surface with sodium dodecyl sulfate (SDS). A detailed investigation by transmission electron microscopy (TEM) and electrochemistry is performed in order to elucidate the preparation process and properties of the nanocomposites. TEM image shows that the particle size of HoFNPs is about 56nm. Linear calibration plot is obtained over the range 2.0×10−7–5.0×10 −4 M (0.2–500.0μM) with a detection limit 1.6×10−7 M (0.16μM) for UA. The modified carbon electrode proves to have good sensitivity, stability and performance for determination UA in the presence of AA, DA in human blood serum and urine samples. [ABSTRACT FROM AUTHOR]

Background: Promising reports exist regarding the use of arsenic trioxide (ATO) as first-line treatment in acute promyelocytic leukemia (APL). Although the in vitro effect of ATO is extensively studied, the in vivo mechanism(s) of ATO action is mostly unknown. Patients and methods: Newly diagnosed APL patients were involved and received ATO (0.15 mg·kg/day) for 28 days as induction followed by consolidation therapy. Bone marrow (BM) aspirates were obtained on days 0, 14 and 28 of treatment for further molecular studies. Clinical findings and white blood cell counts were recorded as well. Results: Complete remission was observed in 17 (85%) patients with the median duration of 28 days (18-38) and cumulative dosage of median 280 mg (180-350). Hyperleukocytosis and APL differentiation syndrome (63%), gastrointestinal disorders (30%), liver enzyme elevation and night sweating (50%) were the most prevalent side-effects. The expression of Bax, ERK1 and p38 proteins and caspase-3 activity increased significantly in promyelocytes of BM aspirates at days 14 and 28 of induction therapy. Conclusion(s): These findings point toward the role of p38 and Bax in the induction of apoptosis, which was confirmed by increase in caspase-3 activity. However, the increase in ERK1 expression with regard to leukocytosis could translate to a proliferative/differentiation effect. [ABSTRACT FROM AUTHOR]