1,000 research outputs found
Low-energy structure of the intertwining double-chain ferrimagnets A_3_Cu_3_(PO_4_)_4_ (A=Ca,Sr,Pb)
Motivated by the homometallic intertwining double-chain ferrimagnets
A_3_Cu_3_(PO_4_)_4_ (A=Ca,Sr,Pb), we investigate the low-energy structure of
their model Hamiltonian H=\sum_n_[J_1_(S_{n :1}_+S_{n :3}_)
+J_2_(S_{n+1:1}+S_{n-1:3}_)]\cdotS_{n:2}_, where S_{n:l}_ stands for the
Cu^{2+}^ ion spin labeled l in the nth trimer unit, with particular emphasis on
the range of bond alternation 0<J_2/J_1<1. Although the spin-wave theory,
whether up to O(S^1^) or up to O(S^0^), claims that there exists a flat band in
the excitation spectrum regardless of bond alternation, a perturbational
treatment as well as the exact diagonalization of the Hamiltonian reveals its
weak but nonvanishing momentum dispersion unless J_2_=J_1_ or J_2_=0. Quantum
Monte Carlo calculations of the static structure factor further convince us of
the low-lying excitation mechanism, elucidating similarities and differences
between the present system and alternating-spin linear-chain ferrimagnets.Comment: 8 pages, 6 figure
Direct genomic sequencing of bacterial DNA: the pyruvate kinase I gene of Escherichia coli.
Ten Years» Experience of Aortic Aneurysm Associated with Systemic Lupus Erythematosus
AbstractBackground: aortic aneurysm is a rare but life-threatening cardiovascular complication in patients with systemic lupus erythematosus (SLE). The purpose of this study was to clarify the characteristic clinical features and the pathological mechanism of aneurysmal formation in these patients. Methods: among 429 patients operated on for abdominal aortic aneurysm (AAA) during the past 10 years, five cases with SLE were treated surgically. Their clinical data were reviewed, and the resected aneurysmal wall of the five patients was also examined histologically. Results: the mean age of the patients with SLE was 55 years, which was statistically younger than that of the other patients (mean 77 years, s.d. 7.9, p <0.05). They had received long-term corticosteroid therapy for the treatment of SLE for a mean of 23 years. Histologically, destruction of the medial elastic lamina was characteristic. Four patients had no complications in the postoperative follow-up period (mean 4 years), while the remaining patient died of rupture of a dissecting aneurysm two years after operation.Conclusion : prolonged steroid therapy may play a major role in accelerating atherosclerosis, which can result in aortic aneurysmal enlargement, possibly together with primary aortic wall involvement and/or vasculitic damage in patients with SLE
Integrated Co-Professional Evaluation? Converging Approaches to School Evaluation Across Frontiers
This paper posits that almost all inspectorates are now following, if to varying degrees, a similar overarching ideology and methodology for school accountability and improvement. The first part of the paper provides an analysis of recent changes to school inspection policies across Frontiers. Using Ireland as a case example, the next part of the paper provides an analysis of Irish school inspection policies and practices that appear to mirror other school inspection systems. To test these assumptions, the paper then provides an analysis of a key informant interview with the Chief Inspector of schools in Ireland.
The evidence suggests that there is an increasingly convergent approach to school evaluation discernible across all inspection frontiers. Among the many aspects of this changing landscape is the rapid pace at which schools have accepted school inspection frameworks and the emergence of a genuinely co-professional as opposed to co-existent mode of evaluation between the inspectorate and schools
INFLUENCE OF INFORMATION SOURCES ON FARMERS’ INDIGENOUS KNOWLEDGE OF SOIL FERTILITY MANAGEMENT IN NIGERIA
This study assessed the influence of information sources on farmers’ indigenous knowledge on soil fertility management in Nigeria. Multi-stage sampling technique was employed to select one hundred and eighty respondents and the instrument for data collection was the questionnaire. Data collected were analyzed using descriptive statistics of simple frequency and percentage. The findings show that majority of the farmers sampled were female 57.2%, single 50.5%; and tertiary education 39.5%. The result on the sources of farmers’ information about soil fertility management indicated that television was 31.7%, and social media accounted for 31.1% of the total respondents while extension agents accounted for 22.2%. Indigenous ways of determining soil fertility by respondents was by crop appearance 55.5% followed by 22.2% for soil color, whereas indigenous way of soil fertility management by respondents was shifting cultivation 22.2%. Information source highly influence indigenous soil fertility management. It is recommended that government should increase their support for agricultural extension services to fulfill their mandate of appropriate information dissemination to farmers
Проблема конкуренції криінально-правових норм (кримінальних законів) у науці пострадянського (радянського) кримінального права та в науці кримінального права держав, які відносяться до романо-германської правової сім'ї
У статті проаналізовано наукові погляди на конкуренцію кримінально-правових норм (кримінальних законів) у теорії пострадянського (радянського) кримінального права та в теорії кримінального права держав, які відносяться до романо-германської правової сім'ї. Ключові слова: конкуренція кримінально-правових норм, конкуренція законів.В статье анализируются научные взгляды на конкуренцию уголовно-правовых норм (уголовных законов) в теории постсоветского (советского) уголовного права и в теории уголовного права государств, которые относятся к романо-германской правовой семье. Ключевые слова: конкуренция уголовно-правовых норм, конкуренция законов.In the article scientific looks are analyzed to the competition of criminal law norm’s (criminal laws) in the theory of post-soviet (soviet) criminal law and in the theory of criminal law of the states which behave to the legal system of civil law. Key words: competition of criminal law norm’s, competition of laws
Effect of Additive on Crystallization and Mechanical Properties of Polymer Blends of Poly(Lactic Acid) and Poly[(Butylene Succinate)-co-Adipate]
AbstractThe effect of additive on crystallization and mechanical properties of poly(lactic acid) (PLA) and poly(butylene succinate-co-adipate) (PBSA) blend was studied. PLA and PBSA were blended in a twin screw extruder, which incorporated poly(butylene adipate-co-terephthalate) (PBAT) as an additive in PLA/PBSA blend. The ratio of PLA/PBSA was 80/20. The contents of PBAT were varied from 0 to 50 wt%. The thermal properties and crystallization behavior of PLA/PBSA/PBAT blends were analyzed by differential scanning calorimetry. The effect of PBAT contents on non-isothermal crystallization kinetic of the composites was investigated by using Avrami equation. Tensile strength and impact performance of the PLA/PBSA/PBAT blends decreased when increasing PBAT contents. It can be noted that the addition of 20 wt% PBAT showed the maximum impact performance of the PLA/PBSA blends
Shift of the molecular bound state threshold in dense ultracold Fermi gases with Feshbach resonance
We consider a dense ultracold Fermi gas in the presence of a Feshbach
resonance. We investigate how the treshold for bound state formation, which is
just at the Feshbach resonance for a dilute gas, is modified due to the
presence of the Fermi sea. We make use of a preceding framework of handling
this many-body problem. We restrict ourselves to the simple case where the
chemical potential is negative, which allows us to cover in particular
the classical limit where the effect is seen to disappear. We show that, within
a simple approach where basically only the effect of Pauli exclusion is
included, the Fermi sea produces a large shift of the threshold, which is of
order of the width of the Feshbach resonance. This is in agreement with very
recent experimental findings.Comment: one reference adde
Aerosol route as a feasible bottom-up chemical approach for up-converting phosphor particles processing
Proocedings of: Fourth Conference on the Characterization and Control of Interfaces for High Quality Advanced Materials. Kurashiki, Japan, 02-05 September 2012.The opportunities of the hot wall aerosol synthesis, i.e. conventional spray pyrolysis (CSP) method are demonstrated for the generation of highly spherical three-dimensional (3D) nanostructured phosphor particles with uniformly distributed components, phases and nano-clustered inner structure. With the presumption that certain particle morphology is formed during the evaporation/drying stage, the aerosol transport properties and powder generation are correlated with the particles structural and morphological features. With the help of various analyzing techniques like Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM) coupled with energy dispersive X-ray Analysis and STEM mode (TEM/EDS), X-ray Powder Diffraction (XRPD) and fluorescence measurements the feasible processing of up-conversion rare-earth Y2O3:Er, Yb phosphors powders are discussed.The financial support for this work is provided by the Ministry of Education, Science and Technological Development of the Republic of Serbia Project No. 172035 and JSPS fellowship, 2011/2012 (O.M.).Publicad
Nonadditive entropy and nonextensive statistical mechanics - Some central concepts and recent applications
We briefly review central concepts concerning nonextensive statistical
mechanics, based on the nonadditive entropy . Among others, we focus on
possible realizations of the -generalized Central Limit Theorem, including
at the edge of chaos of the logistic map, and for quasi-stationary states of
many-body long-range-interacting Hamiltonian systems.Comment: 15 pages, 9 figs., to appear in Journal of Physics: Conf.Series (IOP,
2010
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