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Amplified warming in subarctic regions is having measurable impacts on terrestrial and freshwater ecosystem processes. At the boundary of the discontinuous and continuous permafrost zones, and at the northern extent of the boreal forest, the Hudson Bay Lowlands has experienced, and is projected to continue to experience dramatic rates of climate change in the coming decades. In this review, we explore the impacts of climate change on terrestrial and freshwater ecosystems in the Hudson Bay Lowlands and other environmental processes that mediate these impacts. We surveyed published literature from the region to identify climate indicators associated with impacts on snowpacks, ponds, vegetation, and wood frogs. These climate indicators were calculated using statistically downscaled climate projections, and the potential impacts on ecosystem processes are discussed. While there is a strong trend towards longer and warmer summers, associated changes in the vegetation community mean that snowpacks are not necessarily decreasing, which is important for freshwater ponds dependent on snowmelt recharge. A clear throughline is that the impacts on these ecosystem processes are complex, interconnected, and nonlinear. This review provides a framework for understanding the ways in which climate change has and will affect subarctic regions.

AimsWe report the long-term clinical and radiological outcomes of a consecutive series of 200 total ankle arthroplasties (TAAs, 184 patients) at a single centre using the Scandinavian Total Ankle Replacement (STAR) implants.Patients and MethodsBetween November 1993 and February 2000, 200 consecutive STAR prostheses were implanted in 184 patients by a single surgeon. Demographic and clinical data were collected prospectively and the last available status was recorded for further survival analysis. All surviving patients underwent regular clinical and radiological review. Pain and function were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scoring system. The principal endpoint of the study was failure of the implant requiring revision of one or all of the components. Kaplan–Meier survival curves were generated with 95% confidence intervals and the rate of failure calculated for each year.ResultsA total of 84 patients (87 ankles) were alive by the end of this study. Of the surviving 84 patients (87 ankles; rheumatoid arthritis (RA), n = 40; OA, n = 47), 45 were women and 39 were men, with a mean age of 54 years (18 to 72 years) at the time of surgery. A total of 32 implants failed (16%), requiring revision surgery. The mean time to revision was 80 months (2 to 257). The implant survival at 15.8 years, using revision as an endpoint, was 76.16% (95% confidence interval (CI) 64.41 to 87.91). We found a steady but low decrease in survival over the study period. The mean AOFAS score improved from 28 (10 to 52) preoperatively to 61 (20 to 90) at long-term follow-up.ConclusionSTAR prostheses in the United Kingdom have now been largely superseded by newer design TAAs, potentially with improved characteristics and surgical techniques. The long-term survivorship for the STAR prosthesis can provide a benchmark for these later designs of ankle arthroplasty.

The intercalated disc (ICD) orchestrates electrochemical and mechanical communication between neighboring cardiac myocytes, properties that are perturbed in heart failure (HF). Although structural data from transmission electron microscopy two-dimensional images have provided valuable insights into the domains forming the ICD, there are currently no three-dimensional (3D) reconstructions for an entire ICD in healthy or diseased hearts. Here, we aimed to understand the link between changes in protein expression in an ovine tachypacing-induced HF model and ultrastructural remodeling of the ICD by determining the 3D intercalated disc architecture using serial block face scanning electron microscopy. In the failing myocardium there is no change to the number of ICDs within the left ventricle, but there is an almost doubling of the number of discs with a surface area of <1.0 × 108μm2in comparison to control. The 3D reconstructions further revealed that there is remodeling of the plicate domains and gap junctions with vacuole formation around and between the contributing membranes that form the ICDs in HF. Biochemical analysis revealed upregulation of proteins involved in stabilizing the adhesive and mechanical properties consistent with the morphological changes. Our studies here have shown that in tachypacing-induced HF mechanical stresses are associated with both structural and molecular alterations. To our knowledge, these data together provide novel insights as to how remodeling at the molecular and structural levels leads to impaired intercellular communication.

There is considerable interest in reducing the volume of gas escaping around the blade tips in a gas turbine by fixing an abrasive, such as c-BN, onto the blade tip with an alloy, such as MCrAlY. Abrasion testing at 1100°C showed that the MCrAlY deformed and the abrasive particles oxidised. The shear stress in the MCrAlY was estimated by finite element methods to be in the range of 5–30 MPa, while measurements of the frictional heating suggest the local temperature is between 1100 and 1200°C. Creep testing showed that conventional MCrAlYs were too weak under these conditions. However, higher strengths were obtained using a continuous reinforcing phase together with NiAl. An Al2O3/ZrO2abrasive was investigated as a more oxidation resistant abrasive. In this case, reaction with the MCrAlY caused Ni to diffuse into the abrasive forming layers of NiO, weakening the particles and causing premature failure.

Symbolic Computationand Satisfiability Checkingare viewed as individual research areas, but they share common interests in the development, implementation and application of decision procedures for arithmetic theories. Despite these commonalities, the two communities are currently only weakly connected. We introduce a new project SC2to build a joint community in this area, supported by a newly accepted EU (H2020-FETOPEN-CSA) project of the same name. We aim to strengthen the connection between these communities by creating common platforms, initiating interaction and exchange, identifying common challenges, and developing a common roadmap. This abstract and accompanying poster describes the motivation and aims for the project, and reports on the first activities.

Accurate and comprehensible knowledge about the position of branch cuts is essential for correctly working with multi-valued functions, such as the square root and logarithm. We discuss the new tools in Maple 17 for calculating and visualising the branch cuts of such functions, and others built up from them. The cuts are described in an intuitive and accurate form, offering substantial improvement on the descriptions previously available.

We present the results of a study into the noise behaviour of an Avaspec-3648 CCD UV spectrometer for use in a spectroscopic gas detection system. A comparison was made between a deuterium UV lamp and a range of newly developed UV LEDs. A number of noise phenomena were identified and quantified including source fluctuation noise, photo-response non-uniformity (PRNU), dark current noise, fixed pattern noise (FPN) and read noise. For spectral measurements the dominant noise phenomenon was PRNU, giving a noise equivalent absorption (NEA) of 8 x 10-3AU. A set of noise limitation techniques is presented, which decreases the NEA to 2 x 10-3AU.

ABSTRACTJNJ-Q2 is a fluoroquinolone with broad coverage including methicillin-resistant Staphylococcus aureus(MRSA). A double-blind, multicenter, phase II noninferiority study treated 161 patients for 7 to 14 days, testing the efficacy of JNJ-Q2 (250 mg, twice a day [BID]) versus linezolid (600 mg, BID) in patients with acute bacterial skin and skin structure infections (ABSSSI). The prespecified criterion for noninferiority was 15%. Primary intent-to-treat analysis was unable to declare noninferiority, as the risk difference lower bound of the 95% confidence interval between treatments was 19% at 36 to 84 h postrandomization for the composite end point of lesion assessment and temperature. Prespecified clinical cure rates 2 to 14 days after completion of therapy were similar (83.1% for JNJ-Q2 versus 82.1% for linezolid). Post hocanalyses revealed that JNJ-Q2 was statistically noninferior to linezolid (61.4% versus 57.7%, respectively; P= 0.024) based on the 2010 FDA guidance, which defines treatment success as lack of lesion spread and afebrile status within 48 to 72 h postrandomization. Despite evidence of systemic disease, <5% of patients presented with fever, suggesting fever is not a compelling surrogate measure of systemic disease resolution for this indication. Nausea and vomiting were the most common adverse events. Of the patients, 86% (104/121) had S. aureusisolated from the infection site; 63% of these were MRSA. The results suggest JNJ-Q2 shows promise as an effective treatment for ABSSSI, demonstrating (i) efficacy for early clinical response (i.e., lack of spread of lesions and absence of fever at 48 to 72 h), and (ii) cure rates for ABSSSI pathogens (especially MRSA) consistent with the historical literature.