Miracle-dz/UniFAR-FTUs huggingface dataset:
A non‐isolated DC‐DC converter with low voltage stress and high step‐down voltage conversion ratio

Correspondence Stylianos P. Syrigos, Laboratory of Electromechanical Energy Conversion, Department of Electrical and Computer Engineering, University of Patras, RionPatras 26504, Greece. Email: ssyrigos@ece.upatras. gr Abstract This work focuses on a new non-isolated interleaved DC-DC converter with very high step-down voltage conversion ratio. By employing the switched/series capacitor concept, along with the proper component interconnection, the converter features a high step-down voltage conversion ratio where, in the private case of equal duty ratios, it is six times higher than the conventional buck converter. This high step-down voltage conversion ratio is achieved with the lowest number of components compared to other similar topologies of the same conversion ratio. Also, due to the blocking/series capacitors, the voltage stress on the switches is reduced, improving the converter efficiency. One of the key features of the proposed converter is the inherent automatic current sharing between the interleaved phases, which in the case of equal duty ratios, is uniformly distributed. To add on, due to the use of only two interleaved phases, the converter has a wide output voltage range, since the duty cycle can be extended to 0.5. To validate the proposed converter operation, a 250 W wide-input/wide-output experimental prototype was built, achieving a peak efficiency of 94%.
A Theoretical Analysis on Sampling Size in WiFi Fingerprint-Based Localization

This paper deals with a key problem in WiFi fingerprint-based localization, namely how to sample a sufficient number of received signal strength (RSS) measurements during an offline site survey. To this end, a probabilistic framework is firstly presented to characterize the ability of distinguishing two fingerprints, and is then applied in both the ideally infinite sampling case and the realistically finite sampling case with correlated samples. On these grounds, it is shown that the Euclidean distance between the vectors of mean RSS measurements at any two positions is the key factor of determining localization performance, and how several other factors affect localization performance. More importantly, based on the central limit theory, a quantitative analysis is conducted to describe the degradation in localization performance introduced by finite and correlated samples. In addition, provided that correlated samples satisfy the first order autoregressive model, an explicit formula is derived to describe the relationship between the correlation coefficient and the sampling sizes, which can be employed to guide the offline site survey. Extensive simulations are conducted to confirm the effectiveness of the probabilistic framework as well as the correctness of different analytical results, and an experiment is also carried out for validation. This paper not only helps to understand the basic mechanism of WiFi fingerprint-based localization, but also provides insightful guidelines for efficiently building a fingerprint database.
Dividend Policy and Share Price Volatility: Evidence from Listed Non-Financial Firms in Sri Lanka

The prime objective of this research is to investigate the impact of dividend policy on share price volatility in Colombo Stock Exchange (CSE). A sample of 81 listed non -financial firms from CSE in Sri Lanka is examined using panel data analysis for a five years period from 2013 to 2017. Dividend policy of the firms has been measured by dividend pay-out, dividend yield and dividend per share and which are explanatory variables of the study after controlling for firm size and financial leverage. According to the random effect regression analysis, only 25% of the movements in share prices are explained by the explanatory variables considered in this study. Dividend yield shows significant positive impact on share price volatility whereas dividend per share shows the significant negative impact on share price movements. Firm size illustrates significant negative influence on share price volatility by indicating large size of companies share price volatility is high. But, dividend pay-out and financial leverage are not significantly persuaded on share price volatility in this study. Therefore, it is concluded that dividend yield, dividend per share and firm size have significant impact on price volatility in Sri Lankan context and findings of the study are in line with the dividend relevance theory. Dividend policy can be considered as the protective mechanism to maintain share price volatility in order to enhance the shareholders wealth.
On globally stable difference schemes for the barotropic vorticity equation on a sphere

In this work we study the global stability of a time discrete semi-implicit difference scheme for the barotropic vorticity equation on a rotating sphere. We prove that there exists an attractor o/T for this scheme and establish its global stability, i.e. the attractor *άτ of the difference scheme at sufficiently small time step τ finds itself in any given neighbourhood of the attractor *4 of the original problem. We show that the difference scheme has uniformly asymptotically stable sets «/#r that contain the attractor
Job performance: Working conditions of urban teachers in Zimbabwean schools

The tradition in Zimbabwe is that after teachers have completed their initial professional training, they are deployed to all parts of the country by the Ministry of Primary and Secondary Education (MoPSE) with equity in mind so that quality teachers are equally distributed nationwide in pursuit of universal primary education (UPE), which was declared at independence (Government of Zimbabwe [GoZ], 2020). However, those who are usually deployed to remote schools, which are sometimes inaccessible, encounter challenges.
Pd/C Catalyzed Cascade Synthesis of 2‐Arylquinazolinones from 2‐Iodoacetanilides Employing Ammonia and CO Precursors

An efficient and straightforward approach has been demonstrated for 2‐aryl quinazolinones synthesis from 2‐iodoacetanilides using ammonium carbamate/ammonium carbonate and oxalic acid under heterogeneous Pd/C catalyzed conditions. Herein, we have carried out the reactions employing oxalic acid and ammonium carbamate or ammonium carbonate as two gaseous precursors i. e. CO and NH3 respectively for the synthesis of desired quinazolinones in appreciable yields. The protocol followed cascade aminocarbonylation and cyclization under optimized reaction conditions. The protocol exhibited wide functional group tolerance under set reaction conditions and delivered the respective 2‐aryl quinazolinones with great diversity. The heterogeneous Pd/C catalyst was found to be recyclable up to four consecutive runs without significant decrease in catalytic activity.
Phymatolithon atlanticum sp. nov. (Hapalidiales, Rhodophyta) from the northeast Atlantic Ocean

ABSTRACT Phymatolithon atlanticum is newly described from France and Northern Ireland (the United Kingdom) using both molecular (rbcL sequence data, concatenated psbA and COI-5P datasets) and morpho-anatomical analyses. The species shows sequence divergences from other Phymatolithon species by 10.7–15.3% in rbcL, 5.1–9.2% in psbA and 9.6–16.8% in COI-5P. Morpho-anatomically, P. atlanticum is encrusting to lumpy, has slightly sunken female conceptacles with raised rims, lacks buried conceptacles, has five to six rosette cells surrounding tetra/bisporangial conceptacle pores, and has tetra/bisporangial conceptacle roofs that are pitted with depressions as a result of the disintegration of rosette cells. This latter feature is what currently separates the species morpho-anatomically from all other species of Phymatolithon. The tetra/bisporangial conceptacle of P. atlanticum closely resembles those of Lithothamnion crispatum and Leptophytum bornetii and may well represent additional examples of convergent evolution in the non-geniculate coralline algae.
Effects of dietary microbial feed supplement on production efficacy in lactating dairy cows

Graphical Abstract Summary: Conventional dairy probiotics often comprise microbes isolated from the environment, not from the gastrointestinal tracts of ruminants; thus, their capacity to influence cow performance is limited. We tested the effects of dietary microbial feed supplementation on production efficiency and quality in lactating dairy cows using microbes native to the rumen environment. Microbial feed supplementation (MFS) had little to no effect when all cows were considered. However, a retrospective analysis demonstrated that lower-producing cows had increased energy-corrected milk and tended to have increased milk and fat yields, along with increased lactose percentage over time, whereas higher-producing cows had decreased milk yield, increased milk protein percentage, and increased body condition score when fed MFS.
A COVID-19 contextual study of customers’ mistreatment and counterproductive work behavior at coffee cafés

PurposeThe issue of customer mistreatment in food and retail sectors has come under the spotlight during the COVID-19 crisis. The purpose of this paper is to examine the problem in the COVID-19 pandemic context and study its implications for employee counterproductive behavior in the workplace. Specifically, this study aims to investigate the relationship between customer mistreatment and employee counterproductive behavior by considering the mediating role of cognitive rumination and moderating role of servant leadership at coffee cafés that operated during the COVID-19 smart lockdown period.Design/methodology/approachStructured questionnaires were distributed to 479 frontline staff working at cafés and coffee shops located in two large cities of Pakistan. The questionnaire data were analyzed by using bootstrapped regression procedures to determine how the investigated variables influenced counterproductive work behavior during the pandemic.FindingsThe findings revealed a positive influence of customer mistreatment on counterproductive work behavior both directly as well as indirectly in the presence of employee rumination as a mediator. Furthermore, the presence of servant leadership at cafés and coffee shops was found to moderate the impact of customer mistreatment during the pandemic.Originality/valueThe study offers a novel insight into the relationships between mistreatment by customers, counterproductive work behavior, employee rumination and servant leadership in the COVID-19 pandemic context, hitherto unexplored.
To bulk or not to bulk? Intense genetic differentiation of seed dormancy among Stipa lagascae (Poaceae) genotypes accessed and multiplied in arid Tunisia

Many ecological restoration projects involving wild dryland grasses work with bulk‐harvested seed, yet bulking may lead one to overlook and lose genetic variation that turns out to be crucial for restoration success, including specific dormancy breakdown requirements (conditional dormancy) and genetic variation in these. This article reports on the genetic variation of conditional seed dormancy of Stipa lagascae Roem. & Schult. (Poaceae), a winter‐growing bunch grass with high‐grazing value, native to the circum‐Mediterranean areas but threatened with extinction. This grass is a cleistogamous inbreeder whose population remnants exhibit a fine‐grained genetic structure in many ecological traits. Seed from different lineages was obtained at the end of a seed increase program that chose not to bulk seed during seed sourcing, seed increase, nor seed harvesting for final use. Over a period of 3 years, three germination trials were run with seed coming from 15 to 20 different seed lineages and harvested over different years in two related seed increase plots. Seed lineage was the single most important factor explaining differences in conditional dormancy. Seed weight did not add much to explain these differences. The singularity of behavior of each lineage was conserved over the different harvests. Young seed exhibits the strongest differentiation in conditional dormancy. To restore genetically diversified populations of this inbreeding grass, restoration practitioners should avoid to bulk seed during sourcing and seed increase, because unique seed lineages get easily lost unseen. However, seed for final use could be bulk harvested if seed is used when still conditionally dormant.
Assessment and Valorization of Non-Wood Forest Products in Europe: A Quantitative Literature Review

This article presents a quantitative review of non-wood forest products (NWFPs) at the regional scale in Europe. A text mining approach was applied to titles, abstracts, and keywords extracted from articles in the Scopus database. Different investigations, such as concept mapping and specificity analyses of textual corpus, were performed. Our search yielded a massive number of NWFP-related papers. Specifically, research was distributed in different countries, being more prevalent in the Mediterranean and Scandinavian contexts. Several NWFPs were analyzed, with mushrooms, resin, cork, and other forest fruit being the most common ones. Local socioeconomic improvement was one of the major aspects investigated in scientific literature. The proposed methodology applies specific scripts that can be updated, and the output of the present research can be compared with that of the future works. For instance, interest trends of products and methods can be investigated, and gap analyses performed. Finally, the potential implications of this review for researchers and stakeholders are discussed.
Investigation of the dyeing properties of the colorant extracted from Juglans regia L. leaves on cellulosic and protein fabrics

Dyeing properties of different fabric species were investigated using leaf extract of Juglans regia L. For this purpose, the cotton and wool fabrics were dyed using brown napthaquinon colorant extracted from walnut leaves by pre-mordanting, meta-mordanting and post-mordanting methods in the presence of copper sulfate (CuSO4.5H2O), ferrous sulfate (FeSO4.7H2O) and alum sulfate (AIK(SO4)2.12H2O) at medium pH. Color codes were determined with Pantone Color Guide, and K/S and L* a* b* values were determined using color measurement spectrophotometer, and also washing-, crocking-fastness levels were evaluated using gray scale. High fastness colors were obtained in general in the present study.
Desain dan Analisis Tegangan Rangka Alat Simulasi Pergerakan Kendali Terbang Menggunakan Metode Elemen Hingga

Alat simulasi pergerakan kendali terbang merupakan alat peraga untuk menunjukkan mekanisme kerja dari sayap dan ekor pesawat terbang yang mendekati kenyataan. Alat ini bertujuan sebagai metode pembelajaran bagi calon pilot sebelum mengendarai sebuah pesawat terbang. Penelitian ini bertujuan untuk merancang dan menganalisis rangka alat simulasi pergerakan kendali terbang menggunakan metode elemen hingga. Analisis statik dilakukan menggunakan perangkat lunak SolidWorks 2017. Material rangka yang digunakan yaitu baja ASTM A36 dan ASTM A500 ( square hollow section ) dengan ukuran 50 x 50 x 1,2 mm dan 40 x 40 x 1 mm. Beban yang digunakan yaitu 375,25 kg yang merupakan beban sayap dan ekor pesawat. Hasil analisis menunjukkan rancangan rangka aman untuk menahan beban dinamis menggunakan baja ukuran 50 x 50 x 1,2 mm. Hal ini karena material ASTM A36 dan ASTM A500 untuk ukuran 50 x 50 x 1,2 mm memiliki faktor kemanan berturut-turut 2,162 dan 2,724. The flight control movement simulation tool is a visual aid to show the working mechanism of an airplane wing and tail close to reality. This tool aims as a learning method for aspiring pilots before driving an airplane. The study aims to design and analyze a flight control movement simulation frame using the finite element method. Static analysis was performed using SolidWorks 2017 software. The frame material used was ASTM A36 and ASTM 500 steel (square hollow section) with sizes of 50 x 50 x 1.2 mm and 40 x 40 x 1 mm. The load used is 375.25 kg, which is the weight of the aircraft's wing and tail. The analysis results show that a safe frame design to withstand dynamic loads uses 50 x 50 x 1.2 mm steel. The ASTM A36 and ASTM A500 materials for sizes 50 x 50 x 1.2 mm have a safety factor of 2.162 and 2.724, respectively.
Progress of nematic superconductivity in iron-based superconductors

ABSTRACT Despite more than ten years of extensive research, the superconducting mechanism of iron-based superconductors (FeSCs) is still an open question. Generally, the high-temperature superconductivity is often observed with suppression of magnetic ordering, spin-density-wave, or even the structure transition by carrier doping. Furthermore, an electronic state ordering is also observed at temperatures close to or even above these transitions. Due to its proximity to the superconducting state and disappearance near the optimal superconductivity, it has been also suggested to interplay with superconductivity on a phenomenological level. Nevertheless, there is still no direct evidence to bridge the superconductivity to these transitions. Recently, another nematic order was observed in the superconducting state of heavily hole-doped compound AFe As (A = K, Rb, Cs), providing a possibility to explore the superconductivity gap symmetry nature. Here, by reviewing the recent experimental progresses on the nematic superconductivity in the FeSCs, we will introduce the progresses by various methods including the quasi-particle interference from scanning tunneling microscope, anisotropic gap magnitudes from angular resolved photoemission, the upper critical field and the superconducting transition temperatures from transport measurements. In addition, some recent reports and theoretical explanations for experimental results are followed. Graphical abstract
Associations between enjoyable activities and uplifting events: Effects on momentary positive affect in adulthood

Abstract This study examined the effects of participation in enjoyable activities and the experience of uplifting events on individuals’ momentary positive affect (PA) and tested for age differences in these effects. 176 adults (ages 25–66) completed ecological momentary assessments (EMAs) 5 times per day for 14 days. We found that individuals reported higher levels of PA at times when an uplifting event had occurred compared to times when an uplifting event had not occurred (p < 0.05), and this association was amplified among those who participated less frequently in enjoyable activities (p < 0.05). The moderating effect of participation in enjoyable activities was invariant across the sample’s age range. The findings demonstrated that individuals who habitually participated in enjoyable activities experienced higher levels of PA in everyday life. In contrast, individuals who infrequently or never engaged in enjoyable activities depended upon recent uplifting events to experience higher levels of PA.
The importance of the manufacturing sector and locally specific epidemic responses: Lessons from the South Korean experience

ABSTRACT This article sheds light on less discussed but critically important two elements of successful COVID-19 responses without a complete lock-down in South Korea. By exploiting various data, this article shows that fortifying individual sanitation and devising locally specific responses are the most effective response against multiple massive outbreaks in South Korea. This article also shows that the manufacturing sector undergirded the comprehensive virus containment measures through the constant supply of testing kits and personal sanitization products. In the time of an epidemic, while the central government’s epidemic response and medical systems are important, local industry and planning capacity still play a significant role both in outbreak control and minimizing the economic impact of an epidemic to low-income people and vulnerable population.
Impact of nutrient warning labels on choice of ultra-processed food and drinks high in sugar, sodium, and saturated fat in Colombia: A randomized controlled trial

Objective This study assessed nutrient warnings’ impact on product selection and identification of food products high in nutrients of concern in Colombia. Methods In an online experiment (October 2020), 8,061 Colombians were randomized to a nutrient warning, guideline daily amounts (GDA), Nutri-Score, or no-label condition. They viewed two fruit drinks labeled according to their condition, one high in sugar and one not, and completed selection tasks. Next, they assessed four products high in sugar, sodium, and/or saturated fat (“high in” product). Finally, they selected which label would most discourage them from consuming a “high in” product. Results The nutrient warning performed better on most outcomes. Twenty percent of participants exposed to the nutrient warning would purchase the high-sugar fruit drink compared to GDA (24%, p<0.01), Nutri-Score (33%, p<0.001), and no label (29%, p<0.001). GDA performed slightly better than the nutrient warning in identifying the high-sugar fruit drink (91% vs 88%, p<0.001). The nutrient warning best helped participants correctly identify other “high in” products (75% vs. 23% no-label, 26% Nutri-Score, and 43% GDA, all p<0.001) and had the highest perceived message effectiveness (3.86 on 5-point scale vs. 2.97 GDA and 2.70 Nutri-Score, both p<0.001) and lowest likelihood of purchasing “high in” products (2.58 on 5-point scale vs. 3.23 GDA, 3.49 Nutri-Score, and 3.51 no label, all p<0.001). The nutrient warning most discouraged participants from wanting to consume “high in” products. Conclusions Nutrient warnings are a promising policy to help consumers identify and discourage consumption of products high in nutrients of concern. Trial registration Trial Registration: NCT04567004.
Home Food Gardening in Canada in Response to the COVID-19 Pandemic

The lack of academic attention that home food gardening has received in Canada and the United States is surprising, given the many demonstrated benefits of community gardening programs, including increased community cohesion and resilience. The aim of the exploratory study is to explore the current surge in home food gardening and its relationship to the COVID-19 pandemic. A national survey was conducted, consisting of 43 main questions, asking respondents about their home life and food provisioning during COVID-19, the physical characteristics of their food gardens, and their attitudes and beliefs concerning home food production. Survey results show that 51% of respondents grow at least one type of fruit or vegetable in a home garden. Of those, 17.4% started growing food at home in 2020 during COVID-19 pandemic. To gain more insight into just how significant a cause the pandemic lockdown was on home food gardening, follow-up surveys and policy recommendations are suggested.
The reason why the reactive chemical structure of alkenyl succinic anhydride is necessary for efficient paper sizing

ASA-sized handsheets were prepared, and extractability of the size components from the handsheets was studied by either Soxhlet extraction in sheet form with chloroform or 1% Tween 80 extraction in fibrous form. Although a part of size components could not be removed by the Soxhlet extraction, most size components were removed by the 1% Tween 80 extraction at 70°C for 4h. This result indicates that most size components are present in ASA-sized paper without forming ester bonds with hydroxyl groups of cellulose. Scanning electron microscopic observation showed that, when an old ASA emulsion was used in handsheet-making, large flocs of size emulsion particles were formed owing to hydrophobic interactions between the particles, thus resulting that no sizing features appeared on the handsheets. Thus, the reactive chemical structure of ASA molecules in each ASA emulsion particle is necessary for avoiding flocculation of the size emulsion particles in papermaking process.