Experimental determination of phase relations of pyroxenes in the system Na2O-CaO-MgO-Al2O3-SiO2 (NCMAS) at 2.5 GPa and high temperatures

Phase relations of clinopyroxene (Cpx) and orthopyroxene (Opx) in the system Na2O-CaO-MgO-Al2O3-SiO2 (NCMAS) were studied experimentally at 2.5 GPa and a range of temperatures from 1000 to 1300°C using a piston-cylinder apparatus. The compositions of the coexisting Opx and Cpx solid solutions were determined by electron microprobe analysis. The results show that Cpx and Opx solid solutions coexist with a large miscibility gap. The concentrations of Mg2Si 2O6 in Cpx increase substantially with increasing temperatures but the content of NaAlSi2O6 and CaMgSi2O 6 in Opx is very limited. Based on electron microprobe data from this study and the data from previous studies for the three binary systems NaAlSi 2O6-Mg2Si2O6, Mg2Si 2O6-CaMgSi2O6, and NaAlSi2O 6-CaMgSi2O6, the ternary diagram of Mg2Si2O6 - NaAlSi2O6 - CaMgSi2O6 has been constructed. These results can be used empirically as a geothermometer. However, an attempt to develop a thermodynamic model based on the experimental data failed and the problems are discussed

Crystal structure and electronic structure of quaternary semiconductors Cu2_2ZnTiSe4_4 and Cu2_2ZnTiS4_4 for solar cell absorber

We design two new I2-II-IV-VI4 quaternary semiconductors Cu$_2$ZnTiSe$_4$ and Cu$_2$ZnTiS$_4$, and systematically study the crystal and electronic structure by employing first-principles electronic structure calculations. Among the considered crystal structures, it is confirmed that the band gaps of Cu$_2$ZnTiSe$_4$ and Cu$_2$ZnTiS$_4$ originate from the full occupied Cu 3$d$ valence band and unoccupied Ti 3$d$ conducting band, and kesterite structure should be the ground state. Furthermore, our calculations indicate that Cu$_2$ZnTiSe$_4$ and Cu$_2$ZnTiS$_4$ have comparable band gaps with Cu$_2$ZnTSe$_4$ and Cu$_2$ZnTS$_4$, but almost twice larger absorption coefficient $\alpha(\omega)$. Thus, the materials are expected to be candidate materials for solar cell absorber.Comment: 4 pages, 4 figure

Vpliv tehnologije pri poučevanju angleščine ogroženih učencev ali učencev s posebnimi potrebami: sistematični pregled

With the development of technology, the quantity and quality of electronic devices for students learning English as a second or foreign language (ESL/EFL) are on the rise, especially since the outbreak of the Covid-19 pandemic. To facilitate practices in English language education for students with special needs, the researchers conducted a systematic review of the empirical studies of technology tools for ESL/EFL students with learning difficulties published in the previous two decades. This paper presents the study selection process and findings of the review based on 16 peer-reviewed journal articles and one book chapter. The paper reveals the frequent mental and physical difficulties of English language learning and the typical technology tools employed in and out of class. More importantly, this paper discusses the roles of these technology tools in students’ English language acquisition, specifically their effects on student learning outcomes and the students’ perceptions toward them. With limited primary sources, this paper calls for more attention to the use of technology in English language learning of ESL/EFL students identified as at-risk and with learning disabilities and raises some implications for future research and instructional practices. (DIPF/Orig.

Uniform-in-time propagation of chaos for mean field Langevin dynamics

We study the mean field Langevin dynamics and the associated particle system. By assuming the functional convexity of the energy, we obtain the $L^p$-convergence of the marginal distributions towards the unique invariant measure for the mean field dynamics. Furthermore, we prove the uniform-in-time propagation of chaos in both the $L^2$-Wasserstein metric and relative entropy.Comment: 66 pages, 3 figures and 1 table. Contains corrections and enhancements to arXiv:2212.03050v

Contracting with private providers for primary care services: Evidence from urban China

Controversy surrounds the role of the private sector in health service delivery, including primary care and population health services. China's recent health reforms call for non-discrimination against private providers and emphasize strengthening primary care, but formal contracting-out initiatives remain few, and the associated empirical evidence is very limited. This paper presents a case study of contracting with private providers for urban primary and preventive health services in Shandong Province, China. The case study draws on three primary sources of data: administrative records; a household survey of over 1600 community residents in Weifang and City Y; and a provider survey of over 1000 staff at community health stations (CHS) in both Weifang and City Y. We supplement the quantitative data with one-on-one, in-depth interviews with key informants, including local officials in charge of public health and government finance. We find significant differences in patient mix: Residents in the communities served by private community health stations are of lower socioeconomic status (more likely to be uninsured and to report poor health), compared to residents in communities served by a government-owned CHS. Analysis of a household survey of 1013 residents shows that they are more willing to do a routine health exam at their neighborhood CHS if they are of low socioeconomic status (as measured either by education or income). Government and private community health stations in Weifang did not statistically differ in their performance on contracted dimensions, after controlling for size and other CHS characteristics. In contrast, the comparison City Y had lower performance and a large gap between public and private providers. We discuss why these patterns arose and what policymakers and residents considered to be the main issues and concerns regarding primary care services

Self-interacting approximation to McKean-Vlasov long-time limit: a Markov chain Monte Carlo method

For a certain class of McKean--Vlasov processes, we introduce proxy processes that substitute the mean-field interaction with self-interaction, employing a weighted occupation measure. Our study encompasses two key achievements. First, we demonstrate the ergodicity of the self-interacting dynamics, under broad conditions, by applying the reflection coupling method. Second, in scenarios where the drifts are negative intrinsic gradients of convex mean-field potential functionals, we use entropy and functional inequalities to demonstrate that the stationary measures of the self-interacting processes approximate the invariant measures of the corresponding McKean--Vlasov processes. As an application, we show how to learn the optimal weights of a two-layer neural network by training a single neuron.Comment: 42 pages, 1 figure; contains a minor correctio

Incorporating social objectives in evaluating sustainable fisheries harvest strategy

Fisheries management must take account of environmental sustainability, economic profitability, and social benefits generated by the public resources. The traditional approach of maximum economic yield (MEY), however, is yet to consider social objectives in deriving quantitative quotes. Current MEY evaluation framework would be appropriate if the economic rent was distributed back to the public. If public resources are privatized as corporations, the rent largely flows to the owners of large capital in the fishing industry. This is in stark contrast to the aims of benefiting the community as a whole. In this short paper, we promote a socially responsible framework in decision-making of fisheries management. This approach is beyond the fleet-based MEY approach, for it incorporates fleet profitability, chain profitability, employment, environmental concerns, and broad social benefits, in strict accordance with stock sustainability. Recognizing the needs of fishers, as well as the interests of chain sectors and the broader community, is a vital part of ensuring responsible fishery management and a viable future for Australian fisheries. The established framework will provide open view scenarios and enrich the MEY approaches in fisheries management