Sensing Temperature and Stress Distributions on Rock Samples under Mechanical Loading

In the exploration of planetary materials using robotic probes, one of the key priorities is to establish fundamental level understandings on the mechanical response of materials under different levels of loading. In this context, though a number of strength characterisation tools are applied in the space industry, whole-field visualization of stress and temperature distribution on rock samples and their potential relevance to fracture under external loading is not yet well exploited. In this work, we apply two types of tomography namely (i) IR tomography and (ii) PSAT tomography to understand the variation of temperature and shear stress distribution respectively anywhere on the samples at point scale. Sandstone is used as a simulant material here. Potential links between the tomography measures and the fracture strength of the sandstone are revealed in this work

Sensing, measuring and modelling the mechanical properties of sandstone

We present a hybrid framework for simulating the strength and dilation characteristics of sandstone. Where possible, the grain-scale properties of sandstone are evaluated experimentally in detail. Also, using photo-stress analysis, we sense the deviator stress (/strain) distribution at the microscale and its components along the orthogonal directions on the surface of a V-notch sandstone sample under mechanical loading. Based on this measurement and applying a grain-scale model, the optical anisotropy index K0 is inferred at the grain scale. This correlated well with the grain contact stiffness ratio K evaluated using ultrasound sensors independently. Thereafter, in addition to other experimentally characterised structural and grain-scale properties of sandstone, K is fed as an input into the discrete element modelling of fracture strength and dilation of the sandstone samples. Physical bulk scale experiments are also conducted to evaluate the load-displacement relation, dilation and bulk fracture strength characteristics of sandstone samples under compression and shear. A good level of agreement is obtained between the results of the simulations and experiments. The current generic framework could be applied to understand the internal and bulk mechanical properties of such complex opaque and heterogeneous materials more realistically in future

Assessment of microstructural and mechanical properties of hybrid fibrous self-consolidating concretes using ingredients of plastic wastes

This paper focuses on the experimental investigation carried out on self-consolidating concrete (SCC) reinforced with micro-steel fibre and hybrid fibres (combination of micro-steel fibre and recycled high density polyethylene fibre derived from municipal wastes). The physical properties of fresh and hardened concrete including flowability, setting time and durability, the mechanical properties, namely, compressive strength and flexural strength, and microstructural analysis were studied. Micro-steel fibre addition was seen to enhance the flowability of concrete than the non-fibrous and hybrid fibre reinforced concretes. The setting time of SCC mixtures prolonged with the addition of fibres into concrete mixtures. Hybrid fibre reinforced SCC mixtures have displayed reduction in drying shrinkage. The compressive and flexural strengths of the fibre reinforced concretes show a marginal reduction in strength when compared with the strength of unreinforced concrete. The results of the microstructure analysis clearly demonstrate that the hybrid fibres bond well with the cement matrix and stronger than the bonding between micro-steel fibres and cement matrix.Scopu

An observational study to evaluate factors responsible and actions taken for hypertensive patients who are not at blood pressure goal: I-target Goal Study

PubMed ID: 22318207To evaluate the percentage of hypertensive patients who could achieve target blood pressure (TBP) according to the guidelines in the context of recommended measures and the factors responsible for failure. A total of 589 hypertensive patients (59.0% female; mean age: 57.7±10.4 years) were assessed twice for TBP achievement based on 2007 ESH/ESC guidelines and the investigators' view, in addition to the recommended measures and possible causes of failure in hypertension management in this national multi-center (n=99), non-interventional observational study. Only 29.5% of the patients at the first visit and 46.8% at the second visit achieved the TBP levels specified by the guidelines. However, the investigators' evaluation indicated a higher achievement rate at the first (43.5%) as well as the second (69.1%) visit when compared with the guideline-based assessments (P<0.001). The primary reasons identified by the investigators for the failure to reach TBP were non-compliance with dietary recommendations (61.6%) at the first visit and non-compliance with treatment (63.92%) at the second visit. Recommendations for lifestyle were the most commonly identified treatment plan by the investigators at both visits (62.9% and 66.1%, respectively). Although more patients achieved the TBP levels specified by the guidelines for the second visit compared with the first, effective blood pressure control was achieved only in 29.5% of our patients. Interestingly, the investigators had a more optimistic view about their patients' control of hypertension, which may have contributed to a poor achievement of TBP. © 2012 The Japanese Society of Hypertension All rights reserved

SELECTED ORAL COMMUNICATION SESSION SESSION 06: ENDOMETRIOSIS AND SURGERY Monday 4 July 2011 10:00 - 11:30

Introduction: Tubal dysfunction is a leading factor in female infertility. Laparoscopy dye is the gold standard to detect tubal patency (laparoscopic chromohydrotubation, LSC-CHT), but hysterosalpingography (HSG) and hystero-contrast-sonography (HyCoSy) are also widely applied. Using office hysteroscopy guided selective chromopertubation (OHSC-SPT) we aimed to develop a less invasive effective and reproducible method, which can be performed in an outpatient setting without anesthesia.Material and Methods: 23 infertile patients (mean age: 32,77 ? 3,42) were examined before planned laparoscopy. A 2.7 mm optic was used, with a 5.5 mm sheath (EMD Endoscopy Technologies). A 1.7 mm diameter flexible plastic catheter (Cavafix, B-Braun) was introduced through an inbuilt channel of the sheath. Normal saline was used for the distension. The hysteroscope was introduced without grasping or dilatation of the cervix. A diagnostic hysteroscopy is performed first, then the catheter is inserted through the working channel and the tip of it is placed into the tubal orifice, through which methylene blue dye is injected slowly. In the absence of tubal occlusion the blue dye does not appear in the uterine cavity and normal color of the endometrium is seen. With damaged tubal patency the distension media of the uterine cavity turns blue, according to the backflow of the methylene blue. Laparoscopic standard tubal CHT was then performed by an operator uninformed about the OHSC-SPT results and the result were then compared.Results: Both tubes of the 23 patient were examined (N = 46). In 43 cases (93.5%) either there was an agreement with the laparoscopic findings or (5 cases, 11.6%) in spite of presence of the dye in the abdominal cavity, patency couldn't be proved properly at the time of laparoscopy. Three tubes (3 out of 41, 7,3%) were found patent with laparoscopy and were found occluded according to the OHSC-SPT. All of these false positive cases occurred at the beginning of the learning curve.Conclusion: The novel method of OHSC-SPT is an effective, highly minimal invasive method to investigate the tubal patency, which can be performed in an office setting without anesthesia. The OHSC-SPT negative/LSC-CHT positive cases suggest especially high sensitivity for tubal patency, but this finding requires further confirmatio