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Highlights • Code comparisons build confidence in simulators to model interdependent processes. • International hydrate reservoir simulators are compared over five complex problems. • Geomechanical processes significantly impact response of gas hydrate reservoirs. • Simulators yielded comparable results, however many differences are noted. • Equivalent constitutive models are required to achieve agreement across simulators. Geologic reservoirs containing gas hydrate occur beneath permafrost environments and within marine continental slope sediments, representing a potentially vast natural gas source. Numerical simulators provide scientists and engineers with tools for understanding how production efficiency depends on the numerous, interdependent (coupled) processes associated with potential production strategies for these gas hydrate reservoirs. Confidence in the modeling and forecasting abilities of these gas hydrate reservoir simulators (GHRSs) grows with successful comparisons against laboratory and field test results, but such results are rare, particularly in natural settings. The hydrate community recognized another approach to building confidence in the GHRS: comparing simulation results between independently developed and executed computer codes on structured problems specifically tailored to the interdependent processes relevant for gas hydrate-bearing systems. The United States Department of Energy, National Energy Technology Laboratory, (DOE/NETL), sponsored the first international gas hydrate code comparison study, IGHCCS1, in the early 2000s. IGHCCS1 focused on coupled thermal and hydrologic processes associated with producing gas hydrates from geologic reservoirs via depressurization and thermal stimulation. Subsequently, GHRSs have advanced to model more complex production technologies and incorporate geomechanical processes into the existing framework of coupled thermal and hydrologic modeling. This paper contributes to the validation of these recent GHRS developments by providing results from a second GHRS code comparison study, IGHCCS2, also sponsored by DOE/NETL. IGHCCS2 includes participants from an international collection of universities, research institutes, industry, national laboratories, and national geologic surveys. Study participants developed a series of five benchmark problems principally involving gas hydrate processes with geomechanical components. The five problems range from simple geometries with analytical solutions to a representation of the world's first offshore production test of methane hydrates, which was conducted with the depressurization method off the coast of Japan. To identify strengths and limitations in the various GHRSs, study participants submitted solutions for the benchmark problems and discussed differing results via teleconferences. The GHRSs evolved over the course of IGHCCS2 as researchers modified their simulators to reflect new insights, lessons learned, and suggested performance enhancements. The five benchmark problems, final sample solutions, and lessons learned that are presented here document the study outcomes and serve as a reference guide for developing and testing gas hydrate reservoir simulators.

Background Atherosclerosis is one of the main mechanisms of stroke and cardiovascular diseases and is associated with increased risk of recurrent stroke and cardiovascular events. Intima-medial thickness (IMT) is a well-known surrogate marker of atherosclerosis and has been used to predict stroke and cardiovascular events. However, the clinical significance of IMT and IMT change in stroke has not been investigated in well-designed studies. The PreventIon of CArdiovascular events in iSchemic Stroke patients with high risk of cerebral hemOrrhage—Intima-Media Thickness (PICASSO-IMT) sub-study is designed to investigate the effects of cilostazol, probucol, or both on IMT in patients with stroke. Methods PICASSO-IMT is a prospective sub-study of the PICASSO study designed to measure IMT and plaque score at 1, 13, 25, 37, and 49 months after randomization. Results The primary outcome is the change in mean carotid IMT, which is defined as the mean of the far-wall IMTs of the right and left common carotid arteries, between baseline and 13 months after randomization. Conclusion PICASSO-IMT will provide the largest IMT data set in a stroke population and will provide valuable information about the clinical significance of IMT in patients with ischemic stroke.

Purpose: Atypical femoral fracture (AFF), periprosthetic femoral fracture (PPFF) and femoral nonunion (FNU) are recalcitrant challenges for orthopedic surgeons. Teriparatide (TPTD) had been demonstrated to have anabolic effects on bone in various studies. We postulated that adjuvant TPTD after operation would enhance biologic stimulation for bone formation. We investigated (1) whether the adjuvant TPTD could achieve satisfactory union rate of surgically challenging cases such as displaced AFF, PPFF and FNU; (2) whether the adjuvant TPTD could promote development of abundant callus after surgical fixation; (3) whether the adjuvant TPTD had medically serious adverse effects. Materials and Methods: Thirteen patients who agreed to off label use of TPTD in combination of operation were included in this retrospective case series. Median patients’ age was 68.7 years, and there were three male and ten female patients. Their diagnoses were nonunion in six patients and acute fracture in seven. Medical records and radiographic images were reviewed. Results: Twelve of thirteen fractures were united both clinically and radiologically within a year after adjuvant TPTD. Union completed radiologically median 5.4 months and clinically 5.7 months after the medication, respectively. Callus appeared abundantly showing median 1.4 of fracture healing response postoperatively. There was no serious adverse reaction of medication other than itching, muscle cramp, or nausea. Conclusion: Even appropriate surgical treatment is a mainstay of treatment for AFF, PPFF, and FNU, the current report suggested that adjuvant TPTD combined with stable fixation results in satisfactory outcome for the challenging fractures of femur.

When performing cementless hip arthroplasty, it is critical to achieve firm primary mechanical stability followed by biological fixation. In order to achieve this, it is essential to fully understand characteristics of implant design. In this review, the authors review fixation principles for a variety of implants used for cementless hip replacement and considerations for making an optimal selection.

A bio-detection method and devices based on RF electric signals and MEMS are proposed and demonstrated by a label free method. We have fabricated a transmission line, an inductive device, and a capacitive device with silicon-based MEMS technology. Main issues are fabrication of devices by MEMS technology, surface modification from hydrophobic to hydrophilic of a benzocyclobutene (BCB) layer by plasma radiation and RF signal measurement before and after bio-processing. The devices made by MEMS technology consist of a BCB polymer and Cu metal patterns on a silicon substrate. Glucose oxidase (GOx) and poly dimethyldiallyl ammonium chloride (PDAC) are used as a biomolecule target and probe. The measured output of power loss is 0.8 dB at 1.9 GHz, and its value is pretty distinguishable from the noise level. From the above-mentioned results, it is clear that the proposed RF method and designs are very effective and powerful as a label free detection system.

Purpose of review The supraclavicular artery island flap is a rotation flap that offers a versatile reconstructive option for head and neck defects. Recent anatomical studies have improved our understanding of the vascular supply of the supraclavicular artery island flap. Furthermore, several published large series describe the utility and reliability of this flap. In this article, we review the scientific literature describing the vascular anatomy of the supraclavicular artery island flap, its clinical application, and limitations in reconstructing defects in the head and neck region. Recent findings The vascular anatomy and surface markings, optimal flap design, surgical techniques employed to improve reliability, and aesthetic and functional outcomes of the supraclavicular artery island flap in head and neck reconstruction are well documented in the literature. Summary The supraclavicular artery island flap offers a versatile and well tolerated option in reconstruction of head and neck defects with several advantages over more traditional regional flaps and distant-free flaps.

Comparative investigations of the effects of steel-making practices on impact and fracture toughness were studied. From these examinations, impact and fracture toughness of the steels by vacuum carbon deoxidation (VCD) offered the required values; however, those of the steels by modified VCD and silicon-killing practices were secure. The fracture toughness (KIC) was significantly improved by the silicon-killing and the modified VCD. These resulted from the fineness of austenitic grain size and reduction of sulphidic inclusion. It was observed that the grain size of steels by modified VCD and silicon-killing practices was 20 μm, while that of steel by VCD was 50 μm. The sulphidic inclusion contents were reduced in the steels by modified VCD and silicon-killing practices. Furthermore, the effects of cooling rates from austenitizing temperature on the impact toughness in the steel by VCD were also investigated. The impact toughness of the steel by VCD was closely related to the cooling rate. To obtain the secure impact toughness in the steel by VCD, it seems that the recommended minimum cooling rate from the austenitizing temperature should be 15°C min−1.

In this study, experimental investigation has been carried out for the defect detecting capability of two different way of the OW (oscillating wave) voltage test, such as with-cable-charging and without-cable-charging method. For this purpose, two types of OW voltage tests have been performed at the laboratory on the 22.9 kV CN/CV cables in which artificial needle-type and knifecut-type defects were well integrated. Based on the test results, it could be remarked that the with-cable-charging method is more appropriate to the after laying test due to its consistency of the test condition regardless of the cable length under testing.

The purpose of ALT (Accelerated life test) lies in evaluating the failure rate of an item by obtaining expedient information on the lifetest distribution of a material or product by applying stress levels more severe than those specified by standard conditions, in order to greatly reduce the time needed to observe stress reactions or to magnify such reactions within a given time frame so as to ultimately reduce the time, cost, and effort required to evaluate the item. It is not difficult to determine the failure rate at the component level using ALT. However failure rate prediction at the circuit board level is difficult with ALT, because various electrical parameters at the component level have to be taken into account, and determination of accelerated factors is not so easy. This paper describes temperature ALT conducted for the purpose of estimating failure rates and analyzing forms of failure during operation at the circuit board level of a telecommunication system. In this method, a temperature higher than the operational temperature of an item was applied to it in order to generate failure rate data within a short period of time to estimate the failure rate during actual system operation. We proposed systematically the test temperature, test duration, and the sample size for high temperature ALT of the circuit board of a telecommunication system.

Endometriosis is characterized by an abnormal existence of functional endometrial tissue outside the uterine cavity, typically occuring within the pelvis of women in reproductive age. We report two cases with endometriosis of the abdominal wall; the first one in the rectus abdominis muscle and the second one in the surgical scar of previous caesarean incision along with the rectus abdominis muscle. Pre-operative evaluation included magnetic resonance imaging. The masses were dissected free from the surrounding tissue and excised with clear margins. Diagnosis of the excised lesions were verified by histopathology.