Transverse drilling-induced tensile fractures in the West Tuna area, Gippsland Basin, Australia: implications for the in situ stress regime

Drilling-induced tensile fractures (DITFs) have been interpreted on image logs from vertical wells in the Gippsland Basin, offshore southeastern Australia. Interpreted axial (vertical) DITFs have previously been well described worldwide. We also interpret transverse (horizontal) DITFs, which are horizontal fractures that are electrically conductive, non-planar, bimodal and constrained to the tensile region of the wellbore.Elasticity theory predicts formation of both transverse and axial drilling-induced tensile fractures (DITFs) in vertical wells depending on the magnitude of the principal in situ stresses, pore-pressure and mudweight. Drilling-induced tensile fractures initiate in very specific stress environments. Axial DITFs can closely constrain a lower bound to the maximum horizontal stress (S_H max) magnitude where the minimum horizontal (S_h min) stress is known. If transverse DITFs are observed, they can constrain a lower bound to maximum and minimum horizontal stress magnitudes. The observation of transverse DITFs on image logs can constrain the stress field to one on the border of strike-slip and reverse faulting () without requiring knowledge of the S_h min or S_H max magnitude. The observation of transverse DITFs in the West Tuna area combined with wireline log data, leak-off tests and pore pressure data are used to constrain the in situ stress tensor. The interpreted in situ stress tensor lies on the border of a strike-slip and reverse faulting regime (S_H max40.5 MPa/km>S_h min≈S_v21 MPa/km). Interpreted data from leak-off tests in the West Tuna area confirm that S_h minS_v.     

Can aluminium or magnesium be a surrogate for beryllium: A critical investigation of their chemistry

The use of beryllium is still an existing question according to the studies concerning the plasma–wall interactions which are expected to occur in ITER. Prediction of erosion and co-deposition processes for ITER is necessary for the design and the material choice of the first wall. In the current configuration, it is expected that co-deposited layers containing Be, tungsten and possibly carbon will be formed. However, the toxicity of Be limits its use in many experimental facilities around the world. Using aluminium or magnesium as Be replacements in laboratory experiments would solve this problem of toxicity and handling of Be mixed materials. A critical question which automatically arises is the relevance to use Al or Mg regarding the physical and chemical properties of both elements in comparison to the co-deposited layers expected in ITER. This work provides a review of the chemical and physical properties of Al and Mg, in the respect of comparing these properties to those of Be. Thanks to the similarity of its electronegativity to Be, Al can successfully resemble Be in terms of formation of compounds, especially the oxides and possibly the hydrides. However, due to the difference in the nature of the bonding, Mg cannot be a replacement for a possible hydride deposit formation.     

The impact of prenatal maternal stress and optimistic disposition on birth outcomes in medically high-risk women.

A sizable body of evidence indicates that prenatal maternal stress (PNMS) has an adverse impact on birth outcomes, including birth weight and gestational age at delivery. The authors hypothesized that effects of PNMS are attributable in part to dispositions such as pessimism that lead women to view their lives as stressful and that effects of PNMS and disposition on birth outcome are mediated by prenatal health behaviors. Using structural equations modeling procedures, the authors examined prospective impact of PNMS and dispositional optimism on birth weight and gestational age in a medically high-risk sample (N?=?129), controlling for effects of risk and ethnicity. After its strong inverse association with optimism was accounted for, PNMS had no impact on birth outcomes. Women who were least optimistic delivered infants who weighed significantly less, controlling for gestational age. Optimists were more likely to exercise, and exercise was associated with lower risk of preterm delivery. Results suggest that chronic stress in pregnancy may be a reflection of underlying dispositions that contribute to adverse birth outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Automatic video object generation tool: segmentation and tracking of persons in real time

In the field of the multimedia applications, future standards as mpeg4 or mpeg7 allow new image content representation that goes far from the basic compression. This way, the objects of interest become entities that the user can manipulate. Nevertheless, the norm does not specify how objects have to be segmented, even if in some cases this is a complex task. In the framework of the European project m4m (mpeg fo(u)r Mobiles, Medea project Al 16), we have in charge the development of a demonstrator able to segment and track a speaker in videophone and vidéoconférence applications.     

A sensitive enzyme immunoassay (EIA) for the determination of melengestrol acetate (MGA) in adipose and muscle tissues

The development of a sensitive screening method of MGA residues in bovine perirenal fat and muscle based on a competitive microtitration plate enzyme immunoassay is described. The samples were extracted with petroleum ether and purified with octadecyl-silica-cartridges. The detection limit for fat was 0.4ng/g and for muscle tissue 0.05ng/g, much lower than required for reliable detection of positive samples. The mean recovery rates of fortified samples amount to 75%, the mean intraassay variations to 7% and the interassay variation to 13%. Determination limits were validated for fat at 2ng/g and for muscle at 0.1ng/g. The efficiency of the new screening method was successfully demonstrated by the direct comparison to GC-MS and LC-MS methods performed at natural positive samples originating from an animal experiment in which the labelled dose (0.5mg per animal and day) with and without a 48h withdrawal period or 3-fold or 10-fold the amount of MGA, respectively, was fed to Holstein Frisian heifers. In conclusion, this new screening method can be used for sensitive determination of MGA residues in adipose tissues even after low treatment doses or longer withdrawal periods.     

Exploring the limits of stress-enhanced hole mobility

Hole mobility is found to more than double in fabricated p-MOSFETs with SiGe source/drain due to longitudinal compressive stress in the channel exceeding 1 GPa. The maximum observed low-field mobility enhancement is 140% at a simulated stress level of 1.45 GPa. The mobility enhancement is approximately linear with stress at moderate levels but becomes super-linear above 1 GPa. An important consequence of this behavior is that for moderate stress levels, an average channel stress can be used to estimate the performance of transistors with a nonuniform stress distribution across the channel width. Two alternative approaches to model stress-enhanced hole mobility are suggested. Analysis of the physical effects behind the experimental observations reveals the relative roles of band repopulation and mass modulation. In addition, previously published wafer bending experiments with compressive stress levels below 400 MPa are used to implicitly verify the accuracy of the stress simulations.     

Role of nitric oxide in sepsis-associated pulmonary edema

Transient pulmonary hypertension after inhibition of nitric oxide synthase (NOS) does not alter pulmonary reflection coefficients or lymph flows in endotoxemic sheep. To test the effects of persistent pulmonary hypertension induced by N omega-nitro-L-arginine methylester (L-NAME) and of inhaled NO on pulmonary edema, 18 sheep (three groups) were chronically instrumented with pulmonary artery catheters, femoral arterial fiberoptic thermistor catheters, and tracheostomy. The awake, spontaneously breathing animals received Salmonella typhi endotoxin (lipopolysaccharide; LPS) (10 ng/kg/ min) for 28 h. After 24 h, an airflow of 6 L/min was delivered through the tracheostomy. One group of animals (L-NAME/air) received L-NAME intravenously (25 mg/kg + 5 mg/kg/h) and breathed air. The second group (L-NAME/NO) was given L-NAME and NO (40 ppm) was added to the airflow. The third group was given NaCl 0.9% and breathed air (NaCl/air). Extravascular lung water was measured through the double-indicator dilution technique. Endotoxemia caused pulmonary edema, which was aggravated by L-NAME. Breathing of NO normalized pulmonary artery pressure (Ppa) and ameliorated pulmonary edema. Inhalation of NO may therefore be a therapeutic option for pulmonary edema associated with pulmonary hypertension.     

Combined air treatment: Effect of composition of fibrous filters on toluene adsorption and particle filtration efficiency

In order to obtain a system as efficient for collecting particles with a size less than 10 μm (PM₁₀) as removing volatile organic compounds (VOCs), prototype fibrous media containing activated carbon fibers (ACF) associated with non-adsorptive fibers such as cellulose (C) and polyester (PET) fibers have been developed. Influence of process operating parameters on toluene adsorption and particle filtration efficiency was investigated. Particularly, effect of type and ratio of non-adsorptive fibers, degree of beating of cellulose fibers and addition of binders was studied and the impact on physical properties of the medium and its performances for adsorption and particle collection was analyzed.     

The well-being of women who are late deafened.

The main purpose of this study was to examine potential within-group differences in well-being in individuals who experienced postlingual, late deafness between the ages of 13 and 65 years old. Two related issues were also examined: (a) the psychometric qualities of 2 popular measures of well-being when used with this sample and (b) the well-being of individuals who are late deafened compared to normative data on well-being. A sample of 138 women who were late deafened completed an online survey. The results indicated internal consistency and validity (convergent and partial discriminant) of the 2 well-being measures with this sample. Well-being in this sample was significantly lower than that in samples from the general population. Investigation of within-group differences indicated that individuals from lower socioeconomic groups reported lower levels of well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)