153 research outputs found
Cosmic Periods in the Philosophy of Empedocles
The highest human types or lives , which one may go through before attaining the divinity and immortality of fr. 147, are those of benefactors of their fellow man: and finally they come as seers and bards and physicians and leaders among men on earth.1133 The humanistic motive that led Empedocles to see as the ruling forces in nature Love and Strife, which are most familiar to us as forces in the life of man, is also the leading spirit of his physical philosophy.
For some information about the author see
http://www.depauw.edu/news-media/latest-news/details/19840/.
He passed away in 1985
Multiple scattering formalism for correlated systems: A KKR+DMFT approach
We present a charge and self-energy self-consistent computational scheme for
correlated systems based on the Korringa-Kohn-Rostoker (KKR) multiple
scattering theory with the many-body effects described by the means of
dynamical mean field theory (DMFT). The corresponding local multi-orbital and
energy dependent self-energy is included into the set of radial differential
equations for the single-site wave functions. The KKR Green's function is
written in terms of the multiple scattering path operator, the later one being
evaluated using the single-site solution for the -matrix that in turn is
determined by the wave functions. An appealing feature of this approach is that
it allows to consider local quantum and disorder fluctuations on the same
footing. Within the Coherent Potential Approximation (CPA) the correlated atoms
are placed into a combined effective medium determined by the dynamical mean
field theory (DMFT) self-consistency condition. Results of corresponding
calculations for pure Fe, Ni and FeNi alloys are presented.Comment: 25 pages, 5 fig. acepted PR
Faktor-Faktor yang Mempengaruhi Kualitas Sumber Daya Manusia (SDM) di Kabupaten Siak
This study to analize the factors that affect the quality of human resourcesin Siak District, which of life expectancy, literacy rates, average length of school and average real per capita output adjusted. Analysis of the data used is quantitative method with SPSS (Statistical Package of Social Science) version 21.00. The results os test performed using multiple linear regression analysis, it is known that adjusted 100%. This shows all four independent variables influence on the quality of human resources in Siak District. Simultaneous regression test showed that all independent variables in the examined had a significant effect on the quality of human resources in Siak District. The results of the testing partial regression (t-test) showing that variable of life expectancy, literacy rates, average length of school and average real per capita output adjusted significant effect the human development index. Variables that influence the quality of human resources in Siak District is an average of the real per capita output in adjusted.Keywords : human development index
Utility of neutrophil Fcgamma receptor I (CD64) index as a biomarker for mucosal inflammation in pediatric Crohn\u27s disease
BACKGROUND: Neutrophil expression of the Fcgamma receptor I (CD64) is upregulated in adult patients with clinically active inflammatory bowel disease (IBD). We tested the relationship of CD64 with mucosal inflammation and clinical relapse in pediatric Crohn\u27s disease (CD). METHODS: In a cohort of 208 newly diagnosed CD and 43 non-IBD controls, ileal expression of FcgammaRI/S100A9 was determined by RNA sequencing from biopsies obtained at ileocolonoscopy. In a second cohort, we tested for the peripheral blood polymorphonuclear neutrophil (PMN) CD64 index from 26 newly diagnosed CD, 30 non-IBD controls, and 83 children with established CD. RESULTS: Ileal FcgammaRIA mRNA expression was significantly elevated in CD at diagnosis compared with non-IBD controls (P \u3c 0.001), and correlated with ileal S100A9 (calprotectin) expression (r = 0.83, P \u3c 0.001). The median (range) PMN CD64 index for newly diagnosed CD was 2.3 (0.74-9.3) compared with 0.76 (0.39-1.2) for non-IBD controls (P \u3c 0.001) with 96% sensitivity and 90% specificity at the cut point of 1.0. The PMN CD64 index significantly correlated with mucosal injury as measured by the simple endoscopic score for CD (r = 0.62, P \u3c 0.001). Patients with CD in clinical remission receiving maintenance therapy with a PMN CD64 index1.0 (P \u3c 0.01). CONCLUSIONS: An elevated PMN CD64 index is associated with both mucosal inflammation and an increased risk for clinical relapse in pediatric CD. The PMN CD64 index is a reliable marker for sustained remission in patients with CD receiving maintenance therapy
Observation of time-reversal symmetry breaking in the band structure of altermagnetic RuO
Altermagnets are an emerging third elementary class of magnets. Unlike
ferromagnets, their distinct crystal symmetries inhibit magnetization while,
unlike antiferromagnets, they promote strong spin polarization in the band
structure. The corresponding unconventional mechanism of timereversal symmetry
breaking without magnetization in the electronic spectra has been regarded as a
primary signature of altermagnetism, but has not been experimentally visualized
to date. We directly observe strong time-reversal symmetry breaking in the band
structure of altermagnetic RuO by detecting magnetic circular dichroism in
angle-resolved photoemission spectra. Our experimental results, supported by ab
initio calculations, establish the microscopic electronic-structure basis for a
family of novel phenomena and functionalities in fields ranging from
topological matter to spintronics, that are based on the unconventional
time-reversal symmetry breaking in altermagnets
Momentum-resolved electronic structure at a buried interface from soft x-ray standing-wave angle-resolved photoemission
Angle-resolved photoemission spectroscopy (ARPES) is a powerful technique for
the study of electronic structure, but it lacks a direct ability to study
buried interfaces between two materials. We address this limitation by
combining ARPES with soft x-ray standing-wave (SW) excitation (SWARPES), in
which the SW profile is scanned through the depth of the sample. We have
studied the buried interface in a prototypical magnetic tunnel junction
La0.7Sr0.3MnO3/SrTiO3. Depth- and momentum-resolved maps of Mn 3d eg and t2g
states from the central, bulk-like and interface-like regions of La0.7Sr0.3MnO3
exhibit distinctly different behavior consistent with a change in the Mn
bonding at the interface. We compare the experimental results to
state-of-the-art density-functional and one-step photoemission theory, with
encouraging agreement that suggests wide future applications of this technique.Comment: 18 pages, 4 figures and Supplementary Informatio
Energetic, spatial and momentum character of a buried interface: the two-dimensional electron gas between two metal oxides
The interfaces between two condensed phases often exhibit emergent physical
properties that can lead to new physics and novel device applications, and are
the subject of intense study in many disciplines. We here apply novel
experimental and theoretical techniques to the characterization of one such
interesting interface system: the two-dimensional electron gas (2DEG) formed in
multilayers consisting of SrTiO (STO) and GdTiO (GTO). This system has
been the subject of multiple studies recently and shown to exhibit very high
carrier charge densities and ferromagnetic effects, among other intriguing
properties. We have studied a 2DEG-forming multilayer of the form [6 unit cells
STO/3 unit cells of GTO] using a unique array of photoemission
techniques including soft and hard x-ray excitation, soft x-ray angle-resolved
photoemission, core-level spectroscopy, resonant excitation, and standing-wave
effects, as well as theoretical calculations of the electronic structure at
several levels and of the actual photoemission process. Standing-wave
measurements below and above a strong resonance have been introduced as a
powerful method for studying the 2DEG depth distribution. We have thus
characterized the spatial and momentum properties of this 2DEG with
unprecedented detail, determining via depth-distribution measurements that it
is spread throughout the 6 u.c. layer of STO, and measuring the momentum
dispersion of its states. The experimental results are supported in several
ways by theory, leading to a much more complete picture of the nature of this
2DEG, and suggesting that oxygen vacancies are not the origin of it. Similar
multi-technique photoemission studies of such states at buried interfaces,
combined with comparable theory, will be a very fruitful future approach for
exploring and modifying the fascinating world of buried-interface physics and
chemistry.Comment: 34 pages, 10 figure
The CECAM Electronic Structure Library and the modular software development paradigm
First-principles electronic structure calculations are very widely used thanks to the many successful software packages available. Their traditional coding paradigm is monolithic, i.e., regardless of how modular its internal structure may be, the code is built independently from others, from the compiler up, with the exception of linear-algebra and message-passing libraries. This model has been quite successful for decades. The rapid progress in methodology, however, has resulted in an ever increasing complexity of those programs, which implies a growing amount of replication in coding and in the recurrent re-engineering needed to adapt to evolving hardware architecture. The Electronic Structure Library (\esl) was initiated by CECAM (European Centre for Atomic and Molecular Calculations) to catalyze a paradigm shift away from the monolithic model and promote modularization, with the ambition to extract common tasks from electronic structure programs and redesign them as free, open-source libraries. They include ``heavy-duty'' ones with a high degree of parallelisation, and potential for adaptation to novel hardware within them, thereby separating the sophisticated computer science aspects of performance optimization and re-engineering from the computational science done by scientists when implementing new ideas. It is a community effort, undertaken by developers of various successful codes, now facing the challenges arising in the new model. This modular paradigm will improve overall coding efficiency and enable specialists (computer scientists or computational scientists) to use their skills more effectively. It will lead to a more sustainable and dynamic evolution of software as well as lower barriers to entry for new developers
Multi-agent systems in epidemiology: a first step for computational biology in the study of vector-borne disease transmission
<p>Abstract</p> <p>Background</p> <p>Computational biology is often associated with genetic or genomic studies only. However, thanks to the increase of computational resources, computational models are appreciated as useful tools in many other scientific fields. Such modeling systems are particularly relevant for the study of complex systems, like the epidemiology of emerging infectious diseases. So far, mathematical models remain the main tool for the epidemiological and ecological analysis of infectious diseases, with SIR models could be seen as an implicit standard in epidemiology. Unfortunately, these models are based on differential equations and, therefore, can become very rapidly unmanageable due to the too many parameters which need to be taken into consideration. For instance, in the case of zoonotic and vector-borne diseases in wildlife many different potential host species could be involved in the life-cycle of disease transmission, and SIR models might not be the most suitable tool to truly capture the overall disease circulation within that environment. This limitation underlines the necessity to develop a standard spatial model that can cope with the transmission of disease in realistic ecosystems.</p> <p>Results</p> <p>Computational biology may prove to be flexible enough to take into account the natural complexity observed in both natural and man-made ecosystems. In this paper, we propose a new computational model to study the transmission of infectious diseases in a spatially explicit context. We developed a multi-agent system model for vector-borne disease transmission in a realistic spatial environment.</p> <p>Conclusion</p> <p>Here we describe in detail the general behavior of this model that we hope will become a standard reference for the study of vector-borne disease transmission in wildlife. To conclude, we show how this simple model could be easily adapted and modified to be used as a common framework for further research developments in this field.</p
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