Disordered Fe vacancies and superconductivity in potassium-intercalated iron selenide (K2-xFe4+ySe5)

The parent compound of an unconventional superconductor must contain unusual correlated electronic and magnetic properties of its own. In the high-Tc potassium intercalated FeSe, there has been significant debate regarding what the exact parent compound is. Our studies unambiguously show that the Fe-vacancy ordered K2Fe4Se5 is the magnetic, Mott insulating parent compound of the superconducting state. Non-superconducting K2Fe4Se5 becomes a superconductor after high temperature annealing, and the overall picture indicates that superconductivity in K2-xFe4+ySe5 originates from the Fe-vacancy order to disorder transition. Thus, the long pending question whether magnetic and superconducting state are competing or cooperating for cuprate superconductors may also apply to the Fe-chalcogenide superconductors. It is believed that the iron selenides and related compounds will provide essential information to understand the origin of superconductivity in the iron-based superconductors, and possibly to the superconducting cuprates

SIMD Everywhere Optimization from ARM NEON to RISC-V Vector Extensions

Many libraries, such as OpenCV, FFmpeg, XNNPACK, and Eigen, utilize Arm or x86 SIMD Intrinsics to optimize programs for performance. With the emergence of RISC-V Vector Extensions (RVV), there is a need to migrate these performance legacy codes for RVV. Currently, the migration of NEON code to RVV code requires manual rewriting, which is a time-consuming and error-prone process. In this work, we use the open source tool, "SIMD Everywhere" (SIMDe), to automate the migration. Our primary task is to enhance SIMDe to enable the conversion of ARM NEON Intrinsics types and functions to their corresponding RVV Intrinsics types and functions. For type conversion, we devise strategies to convert Neon Intrinsics types to RVV Intrinsics by considering the vector length agnostic (vla) architectures. With function conversions, we analyze commonly used conversion methods in SIMDe and develop customized conversions for each function based on the results of RVV code generations. In our experiments with Google XNNPACK library, our enhanced SIMDe achieves speedup ranging from 1.51x to 5.13x compared to the original SIMDe, which does not utilize customized RVV implementations for the conversions

Tellurium substitution effect on superconductivity of the alpha-phase Iron Selenide

We have carried out a systematic study of the PbO-type compound FeSe_{1-x}Te_x (x = 0~1), where Te substitution effect on superconductivity is investigated. It is found that superconducting transition temperature reaches a maximum of Tc=15.2K at about 50% Te substitution. The pressure-enhanced Tc of FeSe0.5Te0.5 is more than 10 times larger than that of FeSe. Interestingly, FeTe is no longer superconducting. A low temperature structural distortion changes FeTe from triclinic symmetry to orthorhombic symmetry. We believe that this structural change breaks the magnetic symmetry and suppresses superconductivity in FeTe.Comment: Some typing errors are corrected; we take out one figures, now the paper has 14 pages, 5 figure

The Spill-Over Impact of the Novel Coronavirus-19 Pandemic on Medical Care and Disease Outcomes in Non-communicable Diseases: A Narrative Review

OBJECTIVES: The coronavirus-19 (COVID-19) pandemic has claimed more than 5 million lives worldwide by November 2021. Implementation of lockdown measures, reallocation of medical resources, compounded by the reluctance to seek help, makes it exceptionally challenging for people with non-communicable diseases (NCD) to manage their diseases. This review evaluates the spill-over impact of the COVID-19 pandemic on people with NCDs including cardiovascular diseases, cancer, diabetes mellitus, chronic respiratory disease, chronic kidney disease, dementia, mental health disorders, and musculoskeletal disorders. METHODS: Literature published in English was identified from PubMed and medRxiv from January 1, 2019 to November 30, 2020. A total of 119 articles were selected from 6,546 publications found. RESULTS: The reduction of in-person care, screening procedures, delays in diagnosis, treatment, and social distancing policies have unanimously led to undesirable impacts on both physical and psychological health of NCD patients. This is projected to contribute to more excess deaths in the future. CONCLUSION: The spill-over impact of COVID-19 on patients with NCD is just beginning to unravel, extra efforts must be taken for planning the resumption of NCD healthcare services post-pandemic

An Overview of Regional Experiments on Biomass Burning Aerosols and Related Pollutants in Southeast Asia: From BASE-ASIA and the Dongsha Experiment to 7-SEAS

By modulating the Earth-atmosphere energy, hydrological and biogeochemical cycles, and affecting regional-to-global weather and climate, biomass burning is recognized as one of the major factors affecting the global carbon cycle. However, few comprehensive and wide-ranging experiments have been conducted to characterize biomass-burning pollutants in Southeast Asia (SEA) or assess their regional impact on meteorology, the hydrological cycle, the radiative budget, or climate change. Recently, BASEASIA (Biomass-burning Aerosols in South-East Asia: Smoke Impact Assessment) and the 7-SEAS (7- South-East Asian Studies) Dongsha Experiment were conducted during the spring seasons of 2006 and 2010 in northern SEA, respectively, to characterize the chemical, physical, and radiative properties of biomass-burning emissions near the source regions, and assess their effects. This paper provides an overview of results from these two campaigns and related studies collected in this special issue, entitled Observation, modeling and impact studies of biomass burning and pollution in the SE Asian Environment. This volume includes 28 papers, which provide a synopsis of the experiments, regional weatherclimate, chemical characterization of biomass-burning aerosols and related pollutants in source and sink regions, the spatial distribution of air toxics (atmospheric mercury and dioxins) in source and remote areas, a characterization of aerosol physical, optical, and radiative properties, as well as modeling and impact studies. These studies, taken together, provide the first relatively complete dataset of aerosol chemistry and physical observations conducted in the sourcesink region in the northern SEA, with particular emphasis on the marine boundary layer and lower free troposphere (LFT). The data, analysis and modeling included in these papers advance our present knowledge of source characterization of biomass-burning pollutants near the source regions as well as the physical and chemical processes along transport pathways. In addition, we raise key questions to be addressed by a coming deployment during springtime 2013 in northern SEA, named 7-SEASBASELInE (Biomass-burning Aerosols Stratocumulus Environment: Lifecycles and Interactions Experiment). This campaign will include a synergistic approach for further exploring many key atmospheric processes (e.g., complex aerosol-cloud interactions) and impacts of biomass burning on the surface-atmosphere energy budgets during the lifecycles of biomass burning emissions

The charm of impossibilities: Musical language, theology and narrative discourse in Olivier Messiaen's “Et exspecto resurrectionem mortuorum”

My dissertation falls into what Robert Fallon describes as "an ongoing third wave of Messiaen studies" and furthers his recommendation for a new approach in Messiaen scholarship that requires scholars to step away from the established path, adopting new and fresh perspectives from the complex context of Messiaen's cultural, musical, and theological world. In my dissertation, I investigate Messiaen's commissioned work Et exspecto resurrectionem mortuorum (1964) with respect to the cultural, theological and musical elements interpreted in relation to musical semiotics and narrative discourse. Chapter 1 offers a review of the secondary literature related to my general topic and the methodology that I adopt. I provide summaries of notions concerning recent publications in these related fields. These include Byron Almén's A Theory of Musical Narrative, Kofi Agawu's Music as Discourse , and Andrew Shenton's Olivier Messiaen's Systems of Signs: Notes Towards Understanding His Music. Here I explain the analytical strategy that I derive from the secondary literature, as well as my analytical procedures. Chapter 2 surveys Messiaen's harmonic language. Based on Messiaen's Technique de mon langage musical and the seventh volume from Traité de rythme, de couleur et d'ornithologie, I illustrate Messiaen's unique modes of limited transpositions and special color-chords with set-class labels and interval succession for purposes of identification and comparison. I also provide the details of colors that the harmonic complexes carry according to Messiaen's own synaesthetic experience. In Chapters 3 and 4, I begin with identifying Et exspecto as a narrative in itself followed by analyzing each movement in five stages according to the procedures and concepts mentioned: the overall narrative scope, the biblical narrative, the musical narrative, the musical discourse, and the narrative discourse synthesis. The Epilogue at the end of Chapter 4 concludes this dissertation. Based on the analytical results, I indicate fifty topics used in Et exspecto, which help us to understand not only his music, but also his personal beliefs concerning Catholicism and eternity through empathy, speculation, and play

Exploring the physical activity of secondary school students in Hong Kong by application of the theory of planned behaviour

According to World Health Organization (2010), inadequate physical activities ranked the fourth leading cause of global mortality. Diseases caused by lacking physical activity contributed to 6% of global mortality rate. Adequate physical activity is particular important for students. Habits developed in early stage are rooted and more likely maintained throughout the rest of life. According to the survey of Department of Health (Centre for Health Protection, 2010), it revealed that majority of population did not have enough physical activity, there was over 60% of Hong Kong citizens (aged from 18 – 84) could not fulfil the requirements of regular physical activity. In addition, secondary school students in Hong Kong were reported lacking of physical activity (Mok & Ko, 2012). Excluding physical education lessons in school, there were nearly 70 % of children and adolescents did not have adequate amount of physical activity to bring health benefits (Central Health Education Unit, 2005). In present study, the aim was to predict the physical activity intention and behaviour of secondary school students in Hong Kong by application of Ajzen’s theory of planned behaviour (TPB). By doing data analysis, the root TPB variables restraining students from doing physical activity were explored. In this case study, 486 students (250 male and 236 female), ranging in age from 11 to 18 years, were enrolled. By means of self-administrated questionnaire, TPB variables were measured. All three TPB variables, Attitude (A), Subjective Norm (SN) and Perceived Behavioural Control (PBC) had significant associations with physical activity, but PBC gave the strongest influence. The TPB variables explained 53.1% of physical activity intention with significant factors of SN and PBC. When predicting physical activity behaviour, TPB variables accounted for 26.6% of the variance. Results of this study are in line with other research and give evidence that TPB is a useful framework for the prediction of physical activity intention of secondary school students in Hong Kong