Highlights • Overview of factors influencing acceptance of electronic technology for aging in place. • Comparison between pre- and post-implementation factors. • Comparison between results from ...qualitative and quantitative research. • Recommendations for research in this field.
Neutron stars provide a window into the properties of dense nuclear matter. Several recent observational and theoretical developments provide powerful constraints on their structure and internal ...composition. Among these are the first observed binary neutron star merger, GW170817, whose gravitational radiation was accompanied by electromagnetic radiation from a short γ-ray burst and an optical afterglow believed to be due to the radioactive decay of newly minted heavy r-process nuclei. These observations give important constraints on the radii of typical neutron stars and on the upper limit to the neutron star maximum mass and complement recent pulsar observations that established a lower limit. Pulse-profile observations by the Neutron Star Interior Composition Explorer (NICER) X-ray telescope provide an independent, consistent measure of the neutron star radius. Theoretical many-body studies of neutron matter reinforce these estimates of neutron star radii. Studies using parameterized dense matter equations of state (EOSs) reveal several EOS-independent relations connecting global neutron star properties.
► Introduces the Agricultural Model Intercomparison and Improvement Project (AgMIP). ► Describes AgMIP Protocols for consistent research activities. ► Demonstrates AgMIP approaches using climate, ...crop, and economic model analyses. ► Wheat pilot results elucidate the relative uncertainties from crop and climate models. ► Outlines AgMIP crop-specific, regional, and global research activities.
The Agricultural Model Intercomparison and Improvement Project (AgMIP) is a major international effort linking the climate, crop, and economic modeling communities with cutting-edge information technology to produce improved crop and economic models and the next generation of climate impact projections for the agricultural sector. The goals of AgMIP are to improve substantially the characterization of world food security due to climate change and to enhance adaptation capacity in both developing and developed countries. Analyses of the agricultural impacts of climate variability and change require a transdisciplinary effort to consistently link state-of-the-art climate scenarios to crop and economic models. Crop model outputs are aggregated as inputs to regional and global economic models to determine regional vulnerabilities, changes in comparative advantage, price effects, and potential adaptation strategies in the agricultural sector. Climate, Crop Modeling, Economics, and Information Technology Team Protocols are presented to guide coordinated climate, crop modeling, economics, and information technology research activities around the world, along with AgMIP Cross-Cutting Themes that address uncertainty, aggregation and scaling, and the development of Representative Agricultural Pathways (RAPs) to enable testing of climate change adaptations in the context of other regional and global trends. The organization of research activities by geographic region and specific crops is described, along with project milestones.
Pilot results demonstrate AgMIP's role in assessing climate impacts with explicit representation of uncertainties in climate scenarios and simulations using crop and economic models. An intercomparison of wheat model simulations near Obregón, Mexico reveals inter-model differences in yield sensitivity to CO2 with model uncertainty holding approximately steady as concentrations rise, while uncertainty related to choice of crop model increases with rising temperatures. Wheat model simulations with mid-century climate scenarios project a slight decline in absolute yields that is more sensitive to selection of crop model than to global climate model, emissions scenario, or climate scenario downscaling method. A comparison of regional and national-scale economic simulations finds a large sensitivity of projected yield changes to the simulations’ resolved scales. Finally, a global economic model intercomparison example demonstrates that improvements in the understanding of agriculture futures arise from integration of the range of uncertainty in crop, climate, and economic modeling results in multi-model assessments.
As the solar photovoltaic (PV) matures, the economic feasibility of PV projects is increasingly being evaluated using the levelized cost of electricity (LCOE) generation in order to be compared to ...other electricity generation technologies. Unfortunately, there is lack of clarity of reporting assumptions, justifications and degree of completeness in LCOE calculations, which produces widely varying and contradictory results. This paper reviews the methodology of properly calculating the LCOE for solar PV, correcting the misconceptions made in the assumptions found throughout the literature. Then a template is provided for better reporting of LCOE results for PV needed to influence policy mandates or make invest decisions. A numerical example is provided with variable ranges to test sensitivity, allowing for conclusions to be drawn on the most important variables. Grid parity is considered when the LCOE of solar PV is comparable with grid electrical prices of conventional technologies and is the industry target for cost-effectiveness. Given the state of the art in the technology and favourable financing terms it is clear that PV has already obtained grid parity in specific locations and as installed costs continue to decline, grid electricity prices continue to escalate, and industry experience increases, PV will become an increasingly economically advantageous source of electricity over expanding geographical regions.
Continuous Fibre Reinforced Thermoplastic Composites (CFRTPCs) are becoming alternative materials to replace the conventional thermosetting polymers and metals due to excellent mechanical ...performance, recycling and potential used in lightweight structures. Fused deposition modelling (FDM) is a promising additive manufacturing technology and an alternative of conventional processes for the fabrication of CFRTPCs due to its ability to build functional parts having complex geometries. The mechanical properties of a built part depend on several process parameters. The aim of this study is to characterize the effect of build orientation, layer thickness and fibre volume content on the mechanical performance of 3D printed continuous fibre reinforced composites components manufactured by a desktop 3D printer. Tensile and three-point bending tests are carried out to determine the mechanical response of the printed specimens. SEM images of fractured surfaces are evaluated to determine the effects of process parameters on failure modes.
It is observed that the effect of layer thickness of nylon samples on the mechanical performance is marginally significant. In addition, continuous fibre reinforced samples show higher strength and stiffness values than unreinforced ones. The results show that carbon fibre reinforced composites exhibit the best mechanical performance with higher stiffness and flat samples exhibit higher values of strength and stiffness than on-edge samples. Additionally, the results show that strength and stiffness increase as fibre volume content increases in most cases but, conversely, the level of increment in mechanical performance is moderate with continued rise in fibre content, particularly in the case of Kevlar® and glass fibres, due to weak bonding between the fibre/nylon layers as well as the presence of increased levels of defects. Finally, the practicality of the results is assessed by testing an evaluation structure.
Restrictive mitral annuloplasty with revascularization is considered the best approach to ischemic mitral regurgitation with heart failure, but late results are controversial. We report late outcome ...in relation to preoperative left ventricular end-diastolic diameter (LVEDD) cutoff values, previously identified to predict intermediate-term left ventricular reverse remodeling.
One hundred consecutive ischemic mitral regurgitation patients underwent restrictive mitral annuloplasty (stringent downsizing by two ring sizes; median size, 26) and coronary revascularization. Survivors were clinically and echocardiographically assessed at intermediate (18 months) and late (mean, 46 months) follow-up.
Early mortality was 8%, and late mortality was 18%. Actuarial 1-, 3-, and 5-year survival rates were 87% +/- 3.4%, 80% +/- 4.1%, and 71% +/- 5.1%. Mortality predictors (Cox regression) were preoperative inotropic support (hazard ratio, 6.2; 95% confidence interval, 2.3 to 16.9) and preoperative LVEDD greater than 65 mm (hazard ratio, 4.5; 95% confidence interval, 1.9 to 10.9). Five-year survival rate for patients with LVEDD of 65 mm or less was 80% +/- 5.2%, versus 49% +/- 11% for LVEDD greater than 65 mm (p = 0.002). At 4.3 years' follow-up, New York Heart Association functional class had improved from 2.9 +/- 0.8 to 1.6 +/- 0.6 (p < 0.01). Mitral regurgitation grade was 0.8 +/- 0.7, and was less than grade 2+ in 85% of patients. Left ventricular reverse remodeling was sustained with time for the LVEDD of 65 mm or less group. Late deaths did not show intermediate-term systolic left ventricular reverse remodeling, indicating a more extensive intrinsic left ventricular abnormality.
At 4.3 years' follow-up, intermediate-term cutoff values for left ventricular reverse remodeling proved to be predictors for late mortality. For patients with preoperative LVEDD of 65 mm or less, restrictive mitral annuloplasty with revascularization provides a cure for ischemic mitral regurgitation and heart failure; however, when LVEDD exceeds 65 mm, outcome is poor and a ventricular approach should be considered.
Accumulation of misfolded proteins in the endoplasmic reticulum triggers a cellular stress response called the unfolded protein response (UPR) that protects the cell against the toxic buildup of ...misfolded proteins. Previously, we reported that UPR activation is increased in Alzheimer's disease (AD) patients. How the UPR relates to the pathological hallmarks of AD is still elusive. In the present study, the involvement of UPR activation in neurofibrillary degeneration in AD was investigated. Immunoreactivity for the phosphorylated UPR activation markers pancreatic ER kinase (pPERK), eukaryotic initiation factor 2α, and inositol-requiring enzyme 1α was observed in hippocampal neurons associated with granulovacuolar degeneration. The percentage of pPERK-immunoreactive neurons was increased in AD cases compared with nondemented control cases and with the Braak stage for neurofibrillary changes. Although absent from neurofibrillary tangles, pPERK immunoreactivity was most abundant in neurons with diffuse localization of phosphorylated tau protein. Additional analyses showed that pPERK immunoreactivity was associated with ubiquitin and the ubiquitin binding protein p62. A strong co-occurrence of immunoreactivity for both pPERK and glycogen synthase kinase 3β in neurons was also observed. Together, these data indicate that UPR activation in AD neurons occurs at an early stage of neurofibrillary degeneration and suggest that the prolonged activation of the UPR is involved in both tau phosphorylation and neurodegeneration in AD pathogenesis.
Abstract
Anaerobic ammonium-oxidizing (anammox) bacteria primarily grow by the oxidation of ammonium coupled to nitrite reduction, using CO2 as the sole carbon source. Although they were neglected ...for a long time, anammox bacteria are encountered in an enormous species (micro)diversity in virtually any anoxic environment that contains fixed nitrogen. It has even been estimated that about 50% of all nitrogen gas released into the atmosphere is made by these ‘impossible’ bacteria. Anammox catabolism most likely resides in a special cell organelle, the anammoxosome, which is surrounded by highly unusual ladder-like (ladderane) lipids. Ammonium oxidation and nitrite reduction proceed in a cyclic electron flow through two intermediates, hydrazine and nitric oxide, resulting in the generation of proton-motive force for ATP synthesis. Reduction reactions associated with CO2 fixation drain electrons from this cycle, and they are replenished by the oxidation of nitrite to nitrate. Besides ammonium or nitrite, anammox bacteria use a broad range of organic and inorganic compounds as electron donors. An analysis of the metabolic opportunities even suggests alternative chemolithotrophic lifestyles that are independent of these compounds. We note that current concepts are still largely hypothetical and put forward the most intriguing questions that need experimental answers.
Anaerobic ammonium-oxidizing (anammox) bacteria make their living from the conversion of ammonium and nitrite into dinitrogen gas using a new route. Here, current concepts on this new route are reviewed and its connection with energy (ATP) conservation and biomass formation is discussed.
To investigate the histopathologic substrate of microbleeds detected on 7T postmortem MRI in autopsy cases with severe cerebral amyloid angiopathy (CAA) and Alzheimer pathology.
Five decedents (mean ...age at death 79.6 ± 5.7 years) with documented severe CAA and Alzheimer pathology on standard neuropathologic examination were selected from a local database. Formalin-fixed coronal brain slices were scanned at 7T MRI, including high-resolution T2- and T2*-weighted sequences. Representative microbleeds from each case were sampled for histopathologic analysis, including the presence of blood, blood breakdown products, and markers of ischemic tissue injury.
On MRI, we identified >300 cortical and 4 subcortical microbleeds. Two out of 15 sampled cortical microbleeds corresponded histologically to erythrocytes (suggestive of recent hemorrhages), 4 to vasculopathies (fibrinoid necrosis in 3 and a cavernoma) without substantial parenchymal tissue injury, and 9 to accumulations of iron-positive siderophages without erythrocytes (suggestive of old hemorrhages) combined with mild to moderate degrees of chronic ischemic tissue injury.
This study provides evidence for heterogeneous pathologic substrates and possibly different pathophysiologic mechanisms underlying MRI-observed cortical microbleeds in the context of advanced CAA and Alzheimer disease.
Increasingly large quantities of biomass are being transported and stored for use in bioenergy applications. This large storage of biomass is liable to undergo self-heating sometimes leading to ...ignition and fire. Numerous studies on both the laboratory scale and by using theoretical analyses have been made in order to predict their behaviour but these are made on the basis of a number of simplifying assumptions. It is clear from studies reported here of self-heating in 40 kt storage piles of wood pellets that the process is much more complex than the simpler models suggest since thermal waves are observed.
•Large scale storage of wood pellets are increasingly important.•Relevant laboratory studies were undertaken.•Measurements made of self-heating in 40 kt wood pellet stores
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