947 research outputs found
Micro-macro relationship between microstructure, porosity, mechanical properties, and build mode parameters of a selective-electron-beam-melted Ti-6Al-4V alloy
The performance of two selective electron beam melting operation modes, namely the manual mode and the automatic ābuild theme modeā, have been investigated for the case of a Ti-6Al-4V alloy (45ā105 Ī¼;m average particle size of the powder) in terms of porosity, microstructure, and mechanical properties. The two operation modes produced notable differences in terms of build quality (porosity), microstructure, and properties over the sample thickness. The number and the average size of the pores were measured using a light microscope over the entire build height. A density measurement provided a quantitative index of the global porosity throughout the builds. The selective-electron-beam-melted microstructure was mainly composed of a columnar prior Ī²-grain structure, delineated by Ī±-phase boundaries, oriented along the build direction. A nearly equilibrium Ī± + Ī² mixture structure, formed from the original Ī²-phase, arranged inside the prior Ī²-grains as an Ī±-colony or Ī±-basket weave pattern, whereas the Ī²-phase enveloped Ī±-lamellae. The microstructure was finer with increasing distance from the build plate regardless of the selected build mode. Optical measurements of the Ī±-plate width showed that it varied as the distance from the build plate varied. This microstructure parameter was correlated at the sample core with the mechanical properties measured by means of a macro-instrumented indentation test, thereby confirming Hall-Petch law behavior for strength at a local scale for the various process conditions. The tensile properties, while attesting to the mechanical performance of the builds over a macro scale, also validated the indentation property measurement at the core of the samples. Thus, a direct correlation between the process parameters, microstructure, porosity, and mechanical properties was established at the micro and macro scales. The macro-instrumented indentation test has emerged as a reliable, easy, quick, and yet non-destructive alternate means to the tensile test to measure tensile-like properties of selective-electron-beam-melted specimens. Furthermore, the macro-instrumented indentation test can be used effectively in additive manufacturing for a rapid setting up of the process, that is, by controlling the microscopic scale properties of the samples, or to quantitatively determine a product quality index of the final builds, by taking advantage of its intrinsic relationship with the tensile properties
Integrative Whole Person Oncology Care in the UK
The term āwhole person cancer careā - an approach that addresses the needs of the person as well as treating the disease - is more widely understood in the UK than its synonym āintegrative oncologyā. The National Health Service (NHS), provides free access to care for all, which makes it harder to prioritise NHS funding of whole person medicine, where interventions may be multi-modal and lacking in cost-effectiveness data. Despite this, around 30% of cancer patients are known to use some form of complementary or alternative medicine (CAM). This is virtually never medically led, and usually without the support or even the knowledge of their oncology teams, with the exception of one or two large cancer centres. UK oncology services are, however, starting to be influenced from three sides; firstly, by well-developed and more holistic palliative care services; secondly, by directives from central government via the sustainable healthcare agenda; and thirdly, by increasing pressure from patient-led groups and cancer charities. CAM remains unlikely to be provided through the NHS, but nutrition, physical activity, mindfulness, and stress management are already becoming a core part of the NHS āLiving With and Beyond Cancerā agenda. This supports cancer survivors into stratified pathways of care, based on individual, self-reported holistic needs and risk assessments, which are shared between healthcare professionals and patients. Health and Wellbeing events are being built into cancer care pathways, designed to activate patients into self-management and support positive lifestyle change. Those with greater needs can be directed towards appropriate external providers, where many examples of innovative practice exist. These changes in policy and vision for the NHS present an opportunity for Integrative Oncology to develop further and to reach populations who would, in many other countries, remain underserved or hard-to-reach by whole person approaches
C3āC4 composition and prior carbon dioxide treatment regulate the response of grassland carbon and water fluxes to carbon dioxide
During May, July and October 2000, we measured the effects of temporarily increasing or decreasing CO2 concentration by 150ā200 Ī¼mol molā1 on daytime net ecosystem CO2 exchange (NEE) and water flux (evapotranspiration, ET) of C3āC4 grassland in central Texas, USA that had been exposed for three growing seasons to a CO2 gradient from 200 to 560 Ī¼mol molā1. Grassland grown at subambient CO2 (\u3c 365 Ī¼mol molā1) was exposed for 2 days to an elevated CO2 gradient (\u3e 365 Ī¼mol molā1). Grassland grown at elevated CO2 was exposed for 2 days to a subambient gradient. Our objective was to determine whether growth CO2 affected the amount by which grassland NEE and ET responded to CO2 switching (sensitivity to CO2)
Naturally acquired antibodies to polymorphic and conserved epitopes of Plasmodium falciparum merozoite surface protein 3
Many studies on the role of merozoite surface protein 3 (MSP3) in immunity against malaria have focused on a conserved section of MSP3. New evidence suggests that polymorphic sequences within MSP3 are under immune selection. We report a detailed analysis of naturally-acquired antibodies to allele-specific and conserved parts of MSP3 in a Kenyan cohort. Indirect and competition ELISA to heterologous recombinant MSP3 proteins were used for antibody assays, and parasites were genotyped for msp3 alleles. Antibody reactivity to allele-specific and conserved epitopes of MSP3 was heterogenous between individuals. Overall, the prevalence of allele-specific antibody reactivity was significantly higher (3D7-specific 54%, K1-specific 41%) than that to a recombinant protein representing a conserved portion of C-terminal MSP3 (24%, P < 0Ā·01). The most abundant IgG subclass was IgG3, followed by IgG1. Allele-specific reactivity to the K1-type of MSP3 was associated with a lower risk of clinical malaria episodes during a 6-month follow-up in individuals who were parasitized at the start of the malaria transmission season (Relative risk 0Ā·41 with 95% confidence interval 0Ā·20ā0Ā·81, P = 0Ā·011). The potential importance of allele-specific immunity to MSP3 should be considered in addition to immunity to conserved epitopes, in the development of an MSP3 malaria vaccine
Probability amplitude in quantum like games
Examples of games between two partners with mixed strategies, calculated by
the use of the probability amplitude are given. The first game is described by
the quantum formalism of spin one half system for which two noncommuting
observables are measured.
The second game corresponds to the spin one case.
Quantum logical orthocomplemented nondistributive lattices for these two
games are presented. Interference terms for the probability amplitudes are
analyzed by using so called contextual approach to probability (in the von
Mises frequency approach). We underline that our games are not based on using
of some microscopic systems. The whole scenario is macroscopic.Comment: Quantum-like model
Climate Impacts on Agriculture: Implications for Forage and Rangeland Production
Projections of temperature and precipitation patterns across the United States during the next 50 yr anticipate a 1.5 to 2Ā°C warming and a slight increase in precipitation as a result of global climate change. There have been relatively few studies of climate change effects on pasture and rangeland (grazingland) species compared to those on crop species, despite the economic and ecological importance of the former. Here we review the literature on responses of pastureland and rangeland species to rising atmospheric CO2 and climate change (temperature and precipitation) and discuss plant and management factors likely to influence pastureland and rangeland responses to change (e.g., community composition, plant competition, perennial growth habit, seasonal productivity, and management methods). Overall, the response of pastureland and rangeland species to increased [CO2] is consistent with the general responses of C3 and C4 vegetation, although exceptions exist. Both pastureland and rangeland species may experience accelerated metabolism and advanced development with rising temperature, often resulting in a longer growing season. However, soil resources will often constrain temperature effects. In general, it is expected that increases in [CO2] and precipitation will enhance rangeland net primary production (NPP) whereas increased air temperatures will either increase or decrease NPP. Much of the uncertainty in predicting how pastureland and rangeland species will respond to climate change is due to uncertainty in future projections of precipitation, both globally and regionally. This review reveals the need for comprehensive studies of climate change impacts on pastureland and rangeland ecosystems that include an assessment of the mediating effects of grazing regimes and mutualistic relationships (e.g., plant roots-nematodes; N-fixing organisms) as well as changes in water, carbon, and nutrient cycling
Monte Carlo Simulation Calculation of Critical Coupling Constant for Continuum \phi^4_2
We perform a Monte Carlo simulation calculation of the critical coupling
constant for the continuum {\lambda \over 4} \phi^4_2 theory. The critical
coupling constant we obtain is [{\lambda \over \mu^2}]_crit=10.24(3).Comment: 11 pages, 4 figures, LaTe
Net grassland carbon flux over a subambient to superambient CO2 gradient
Increasing atmospheric CO2 concentrations may have a profound effect on the structure and function of plant communities. A previously grazed, central Texas grassland was exposed to a 200-Āµmol mol-1 to 550 Āµmol mol-1 CO2 gradient from March to mid-December in 1998 and 1999 using two, 60-m long, polyethylene-covered chambers built directly onto the site. One chamber was operated at subambient CO2 concentrations (200-360 Āµmol mol-1 daytime) and the other was regulated at superambient concentrations (360-550 Āµmol mol-1). Continuous CO2 gradients were maintained in each chamber by photosynthesis during the day and respiration at night. Net ecosystem CO2 flux and end-of-year biomass were measured in each of 10, 5-m long sections in each chamber. Net CO2 fluxes were maximal in late May (c. day 150) in 1998 and in late August in 1999 (c. day 240). In both years, fluxes were near zero and similar in both chambers at the beginning and end of the growing season. Average daily CO2 flux in 1998 was 13 g CO2 m-2 day-1 in the subambient chamber and 20 g CO2 m-2 day-1 in the superambient chamber; comparable averages were 15 and 26 g CO2 m-2 day-1 in 1999. Flux was positively and linearly correlated with end-of-year above-ground biomass but flux was not linearly correlated with CO2 concentration; a finding likely to be explained by inherent differences in vegetation. Because C3 plants were the dominant functional group, we adjusted average daily flux in each section by dividing the flux by the average percentage C3 cover. Adjusted fluxes were better correlated with CO2 concentration, although scatter remained. Our results indicate that after accounting for vegetation differences, CO2 flux increased linearly with CO2 concentration. This trend was more evident at subambient than superambient CO2 concentrations
Observation of surface states on heavily indium doped SnTe(111), a superconducting topological crystalline insulator
The topological crystalline insulator tin telluride is known to host
superconductivity when doped with indium (SnInTe), and for low
indium contents () it is known that the topological surface states are
preserved. Here we present the growth, characterization and angle resolved
photoemission spectroscopy analysis of samples with much heavier In doping (up
to ), a regime where the superconducting temperature is increased
nearly fourfold. We demonstrate that despite strong p-type doping, Dirac-like
surface states persist
Transcriptomics and proteomics show that selenium affects inflammation, ctoskeleton, and cancer pathways in human rectal biopsies
Epidemiologic studies highlight the potential role of dietary selenium (Se) in colorectal cancer prevention. Our goal was to elucidate whether expression of factors crucial for colorectal homoeostasis is affected by physiologic differences in Se status. Using transcriptomics and proteomics followed by pathway analysis, we identified pathways affected by Se status in rectal biopsies from 22 healthy adults, including 11 controls with optimal status (mean plasma Se = 1.43 Ī¼M) and 11 subjects with suboptimal status (mean plasma Se = 0.86 Ī¼M). We observed that 254 genes and 26 proteins implicated in cancer (80%), immune function and inflammatory response (40%), cell growth and proliferation (70%), cellular movement, and cell death (50%) were differentially expressed between the 2 groups. Expression of 69 genes, including selenoproteins W1 and K, which are genes involved in cytoskeleton remodelling and transcription factor NFĪŗB signaling, correlated significantly with Se status. Integrating proteomics and transcriptomics datasets revealed reduced inflammatory and immune responses and cytoskeleton remodelling in the suboptimal Se status group. This is the first study combining omics technologies to describe the impact of differences in Se status on colorectal expression patterns, revealing that suboptimal Se status could alter inflammatory signaling and cytoskeleton in human rectal mucosa and so influence cancer risk
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