bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decision-making, leadership and performance links in private education institutes
Authors: Torlak Nuri Gökhan , Demir Ahmet , Budur Taylan 
Published: March 2021

PurposeThis paper aims to investigate the relationships between participative decision-making, ethical leadership and leadership performance, which might make school leaders quit autocratic behavior and enhance their performance at private K12 schools in Iraq.Design/methodology/approachThe researchers collected data through a questionnaire using a stratified sampling methodology from 207 educators of 10 institutions. The research methodology included demographic analysis, factor analysis, structural equation modeling and mediation analysis.FindingsThe participative decision-making affected moral, knowledge and attitude that contributed to leadership performance. Besides, the only attitude mediated the relationship between participative decision-making and leadership performance.Research limitations/implicationsThe study is limited to private K12 schools in Iraq. Therefore, the findings cannot be generalized. It might guide educational institutes to change their management style.Originality/valueThe study delivers a unique insight into education in Iraq.
Migrants’ remittances and economic growth in Egypt: an empirical analysis from 1980 to 2017
Authors: Qutb Rasha 
Published: March 2021

Purpose
Migrants’ remittances to Egypt have increased considerably in both size and importance over the past 40 years. This increase has made Egypt one of the top remittance recipients in the world and the leading recipient country in the Middle East. As migrant remittances are one of Egypt's main sources of foreign capital, this study aims to identify the impact of these remittances on economic growth.

Design/methodology/approach
The study collects annual data on migrant remittances sent to Egypt during the period 1980–2017. The study uses the Augmented Dickey–Fuller test and Johnsen's Co-integration test to establish long-run relationships between variables. Then, a vector error correction model (VECM) is used to combine long-run and short-run dynamics, and a Granger causality test is performed. Finally, diagnostic tests of the VECM are conducted.

Findings
Results reveal that migrants’ remittances to Egypt are countercyclical in the sense that they have a long-term negative impact on economic growth. These results are determined by the Granger causality between migrants' remittances, inflation rate and imports.

Practical implications
The study can help policymakers to develop appropriate policies to turn migrants' remittances into a reliable source of capital that could result in a stable economic growth.

Originality/value
Although various empirical studies have examined the growth effect of remittances, most of them are based on cross-country data. This study contributes to the field by attempting to close a gap in the literature by empirically analyzing the impact of remittances on a single country over a long period.
Analytical models to estimate the structural behaviour of fused deposition modelling components
Authors: Cerda-Avila Steffany N. , Medellín-Castillo Hugo I. , Lim Theodore 
Published: March 2021

Purpose
The purpose of this study is to evaluate the capability and performance of analytical models to predict the structural mechanical behaviour of parts fabricated by fused deposition modelling (FDM).

Design/methodology/approach
A total of eight existing and newly proposed analytical models, tailored to satisfy the structural behaviour of FDM parts, are evaluated in terms of their capability to predict the ultimate tensile stress (UTS) and the elastic modulus (E) of parts made of polylactic acid (PLA) by the FDM process. This evaluation is made by comparing the structural properties predicted by these models with the experimental results obtained from tensile tests on FDM specimens fabricated with variable infill percentage, perimeter layers and build orientation.

Findings
Some analytical models are able to predict with high accuracy (prediction errors smaller than 5%) the structural behaviour of FDM and categories of similar additive manufactured parts. The most accurate model is Gibson’s and Ashby, followed by the efficiency model and the two new proposed exponential and variant Duckworth models.

Research limitations/implications
The study has been limited to uniaxial loading conditions along three different build orientations.

Practical implications
The structural properties of FDM parts can be predicted by analytical models based on the process parameters and material properties. Product engineers can use these models during the design for the additive manufacturing process.

Originality/value
Existing methods to estimate the structural properties of FDM parts are based on experimental tests; however, such methods are time-consuming and costly. In this work, the use of analytical models to predict the structural properties of FDM parts is proposed and evaluated.
Invertebrate functional traits and terrestrial nutrient cycling: Insights from a global meta‐analysis
Authors: McCary Matthew A. , Schmitz Oswald J. 
Published: March 2021

Abstract

Functional traits are useful for characterizing variation in community and ecosystem dynamics. Most advances in trait‐based ecology to date centre on plant functional traits, although there is an increasing recognition that animal traits are also key contributors to processes operating at the community or ecosystem scale.

Terrestrial invertebrates are incredibly diverse and ubiquitous animals with important roles in nutrient cycling. Despite their widespread influence on ecosystem processes, we currently lack a synthetic understanding of how invertebrate functional traits affect terrestrial nutrient cycling.

We present a meta‐analysis of 511 paired observations from 122 papers that examined how invertebrate functional traits affected litter decomposition rates, nitrogen pools and litter C:N ratios. Based on the available data, we specifically assessed the effects of feeding mode (bioturbation, detritus shredding, detritus grazing, leaf chewing, leaf piercing, ambush predators, active hunting predators) and body size (macro‐ and micro‐invertebrates) on nutrient cycling.

The effects of invertebrates on terrestrial nutrient cycling varied according to functional trait. The inclusion of both macro‐ (≥2 mm) and micro‐invertebrates (<2 mm) increased litter decomposition by 20% and 19%, respectively. All detritivorous feeding modes enhanced litter decomposition rates, with bioturbators, detritus shredders and detritus grazers increasing decomposition by 28%, 22% and 15%, respectively. Neither herbivore feeding mode (e.g. leaf chewers and leaf piercers) nor predator hunting mode (ambush and active hunting) affected decomposition. We also revealed that bioturbators and detritus grazers increased soil nitrogen availability by 99% and 70%, respectively, and that leaf‐chewing herbivores had a weak effect on litterfall stoichiometry via reducing C:N ratios by 11%.

Although functional traits might be useful predictors of ecosystem processes, our findings suggest context‐dependent effects of invertebrate traits on terrestrial nutrient cycling. Detritivore functional traits (i.e. bioturbators, detritus shredders and detritus grazers) are more consistent with increased rates of nutrient cycling, whereas our currently characterized predator and herbivore traits are less predictive. Future research is needed to identify, standardize and deliberately study the impacts of invertebrate functional traits on nutrient cycling in hopes of revealing the key functional traits governing ecosystem functioning worldwide.
Online and face‐to‐face learning: Evidence from students’ performance during the Covid‐19 pandemic
Authors: Chisadza Carolyn , Clance Matthew , Mthembu Thulani , Nicholls Nicky , Yitbarek Eleni 
Published: March 2021

AbstractThis study investigates the factors that predict students' performance after transitioning from face‐to‐face to online learning as a result of the Covid‐19 pandemic. It uses students' responses from survey questions and the difference in the average assessment grades between pre‐lockdown and post‐lockdown at a South African university. We find that students' performance was positively associated with good wifi access, relative to using mobile internet data. We also observe lower academic performance for students who found transitioning to online difficult and who expressed a preference for self‐study (i.e. reading through class slides and notes) over assisted study (i.e. joining live lectures or watching recorded lectures). The findings suggest that improving digital infrastructure and reducing the cost of internet access may be necessary for mitigating the impact of the Covid‐19 pandemic on education outcomes.
The Commercial Determinants of Three Contemporary National Crises: How Corporate Practices Intersect With the COVID‐19 Pandemic, Economic Downturn, and Racial Inequity
Authors: MAANI NASON , VAN SCHALKWYK MAY CI , PETTICREW MARK , GALEA SANDRO 
Published: March 2021

Policy Points
The United States finds itself in the middle of an unprecedented combination of crises: a global pandemic, economic crisis, and unprecedented civic responses to structural racism.
While public sector responses to these crises have faced much justified criticism, the commercial determinants of these crises have not been sufficiently examined.
In this commentary we examine the nature of the contributions of such actors to the conditions that underpin these crises in the United States through their market and nonmarket activities.
On the basis of this analysis, we make recommendations on the role of governance and civil society in relation to such commercial actors in a post‐COVID‐19 world.
Reducing administrative costs in US health care: Assessing single payer and its alternatives
Authors: Scheinker David , Richman Barak D. , Milstein Arnold , Schulman Kevin A. 
Published: March 2021

AbstractObjectiveExcess administrative costs in the US health care system are routinely referenced as a justification for comprehensive reform. While there is agreement that these costs are too high, there is little understanding of what generates administrative costs and what policy options might mitigate them.Data SourcesLiterature review and national utilization and expenditure data.Study DesignWe developed a simulation model of physician billing and insurance‐related (BIR) costs to estimate how certain policy reforms would generate savings. Our model is based on structural elements of the payment process in the United States and considers each provider's number of health plan contracts, the number of features in each health plan, the clinical and nonclinical processes required to submit a bill for payment, and the compliance costs associated with medical billing.Data ExtractionFor several types of visits, we estimated fixed and variable costs of the billing process. We used the model to estimate the BIR costs at a national level under a variety of policy scenarios, including variations of a single payer “Medicare‐for‐All” model that extends fee‐for‐service Medicare to the entire population and policy efforts to reduce administrative costs in a multi‐payer model. We conducted sensitivity analyses of a wide variety of model parameters.Principal FindingsOur model estimates that national BIR costs are reduced between 33% and 53% in Medicare‐for‐All style single‐payer models and between 27% and 63% in various multi‐payer models. Under a wide range of assumptions and sensitivity analyses, standardizing contracts generates larger savings with less variance than savings from single‐payer strategies.ConclusionAlthough moving toward a single‐payer system will reduce BIR costs, certain reforms to payer‐provider contracts could generate at least as many administrative cost savings without radically reforming the entire health system. BIR costs can be meaningfully reduced without abandoning a multi‐payer system.
Show Me the Money! Dividend Policy in Countries with Weak Institutions
Authors: ELLAHIE ATIF , KAPLAN ZACHARY 
Published: March 2021

ABSTRACTWe hypothesize that, in weak‐institution countries, firms adjust the ‘timing’ of dividend payments by committing to distribute a percentage of current earnings as dividends, revealing the extent of firm‐level agency conflicts to future investors and facilitating the raising of external capital. Consistent with this hypothesis, we find that, on average, firms in weak‐institution countries have a higher speed of adjustment (SOA) to their target payout ratio, pay dividends earlier in the life cycle, and are more likely to disclose a dividend policy committing to pay a minimum percentage of earnings. Within‐country tests show that, in weak‐institution countries, the firms with the highest SOA dividend policies have fewer agency problems and an increased ability to raise external capital. Finally, returns tests around earnings announcements show that high‐SOA dividend policies are associated with larger market reactions to earnings in weak‐institution countries. Collectively, our findings suggest that dividend policy helps to alleviate agency conflicts in weak‐institution countries between firms and (future) investors.
Petrology and Geochemistry of Some Ophiolitic Metaperidotites from the Eastern Desert of Egypt: Insights into Geodynamic Evolution and Metasomatic Processes
Authors: ABDEL‐KARIM Abdel‐Aal M. , AZER Mokhles K. , EL‐SHAFEI Shaimaa A. 
Published: March 2021

AbstractOphiolitic peridotites exposed in the Eastern Desert (ED) of Egypt record multiple stages of evolution, including different degrees of partial melting and melt extraction, serpentinization, carbonatization and metamorphism. The present study deals with metaperidotites at two selected localities in the central and southern ED, namely Wadi El‐Nabá and Wadi Ghadir, respectively. They represent residual mantle sections of a Neoproterozoic dismembered ophiolite that tectonically emplaced over a volcano‐sedimentary succession that represents island–arc assemblages. The studied metaperidotites are serpentinized, with the development of talc‐carbonate and quartz‐carbonate rocks, especially along shear and fault planes. Fresh relics of primary minerals (olivine, orthopyroxene and Cr‐spinel) are preserved in a few samples of partially‐serpentinized peridotite. Most of the Cr‐spinel crystals have fresh cores followed by outer zones of ferritchromite and Cr‐magnetite, which indicates that melt extraction from the mantle protolith took place under oxidizing conditions. The protoliths of the studied metaperidotites were dominated by harzburgites, which is supported by the abundance of mesh and bastite textures in addition to some evidence from mineral and whole‐rock chemical compositions. The high Cr#(0.62–0.69; Av. 0.66) and low TiO2(<0.3 wt%) contents of the fresh Cr‐spinels, the higher Fo (89–92; Av. 91) and NiO (0.24–0.54 wt%, Av. 0.40) contents of the primary olivine relics, together with the high Mg#(0.91–0.93; Av. 91) and low CaO, Al2O3and TiO2of the orthopyroxene relics, are all comparable with depleted to highly depleted forearc harzburgite from a suprasubduction zone setting. The investigated peridotites have suffered subsequent phases of metasomatism, from ocean‐floor hydrothermal alteration (serpentinization) to magmatic hydrothermal alteration. The enrichment of the studied samples in light rare earth elements (LREEs) relative to the heavy ones (HREEs) is attributed to most probably be due to the contamination of their mantle source with granitic source hydrothermal fluids after the obduction of the ophiolite assemblage onto the continental crust. The examined rocks represent mantle residue that experienced different degrees of partial melting (∼10% to 25% for W. El‐Nabá rocks and ∼5% to 23% for W. Ghadir rocks). Variable degrees of partial melting among the two investigated areas suggest mantle heterogeneity beneath the Arabian‐Nubian Shield (ANS).
A Rapid Marine Regression in the Southwestern Tarim Basin in the Latest Cretaceous: Comparison of Two Different Evaporitic Sequences in the Yarkand Basin, Xinjiang Province, China
Authors: CAO Yangtong , ZENG Changmin , ZHANG Liang , ZHU Lichun 
Published: March 2021

AbstractTwo different evaporitic sequences occurred in the latest Cretaceous–Early Paleocene in Yarkand Basin, southwestern Tarim Basin, Xinjiang Province, China: one is characterized by poor gypsum and some small, lenticular‐shaped halite layers in the Tuyiluoke Formation of the latest Cretaceous, the other is characterized by very thick gypsum and halite layers in the Aertashen Formation of the early Paleocene. In the early developmental stage of the Tuyiluoke Formation, the Yarkand ancient saline lake was a long, strip‐shaped depression, NW–SE oriented, along the West Kunlun piedmont, with its eastern boundary to the line along bores Ys1‐T1‐Ks101, the concentrated center located in the area of borehole S1. In the later developmental stage, the depositional scope was shifted inch by inch to the NW of this saline lake, forming a triangular depositional area, with apices at boreholes Wx1, Ak2 and S1, the concentrated center of the saline lake gradually migrating from borehole S1 region to the northwestern area of the lake, developing four small, evaporated‐concentrated sub‐depressions, depositing lenticular‐shaped halite. In the early Paleocene, the ancient saline lake was stretched from the West Kunlun piedmont in the west, to the Markit slope in the east, from the South Tianshan piedmont in the north, to the Hotan area in the south, accompanied by giant thicknesses of halite and large‐scale gypsum layers, mainly interbedded with limestone in the Aertashen Formation. The evaporites in the latest Cretaceous‐early Paleocene were controlled by the marine transgression‐regression geological background in the Yarkand Basin. Generally, integrated evaporitic depositional sequences, such as clasolite‐gypsum‐halite‐potash, usually occur in the presence of persistent seawater through evaporation, but this is not the case in the Tuyiluoke Formation. In contrast, very thick gypsum layers are common in the early Paleocene. Typically, adequate mineral sources for evaporites are found within seawater, such as in large basins undergoing long‐term marine transgression‐regression cycles, where adequate seawater remains, even though the basin was going through a marine regression stage. In the latest Cretaceous, thin gypsum layers indicate a lack of mineral sources. In contrast, the early Paleocene has far larger evaporites, both in width and thickness. This suggests a short‐term marine regression stage must have occurred during the spatiotemporal evolution of the evaporites in the latest Cretaceous–Early Paleocene in the basin, meaning that a rapid marine regressive episode has been identified at the end of the Cretaceous.
Biodiversity Soup II: A bulk‐sample metabarcoding pipeline emphasizing error reduction
Authors: Yang Chunyan , Bohmann Kristine , Wang Xiaoyang , Cai Wang , Wales Nathan , Ding Zhaoli , Gopalakrishnan Shyam , Yu Douglas W. 
Published: March 2021

Abstract

Despite widespread recognition of its great promise to aid decision‐making in environmental management, the applied use of metabarcoding requires improvements to reduce the multiple errors that arise during PCR amplification, sequencing and library generation. We present a co‐designed wet‐lab and bioinformatic workflow for metabarcoding bulk samples that removes both false‐positive (tag jumps, chimeras, erroneous sequences) and false‐negative (‘dropout’) errors. However, we find that it is not possible to recover relative‐abundance information from amplicon data, due to persistent species‐specific biases.

To present and validate our workflow, we created eight mock arthropod soups, all containing the same 248 arthropod morphospecies but differing in absolute and relative DNA concentrations, and we ran them under five different PCR conditions. Our pipeline includes qPCR‐optimized PCR annealing temperature and cycle number, twin‐tagging, multiple independent PCR replicates per sample, and negative and positive controls. In the bioinformatic portion, we introduce Begum, which is a new version of DAMe (Zepeda‐Mendoza et al., 2016. BMC Res. Notes 9:255) that ignores heterogeneity spacers, allows primer mismatches when demultiplexing samples and is more efficient. Like DAMe, Begum removes tag‐jumped reads and removes sequence errors by keeping only sequences that appear in more than one PCR above a minimum copy number per PCR. The filtering thresholds are user‐configurable.

We report that OTU dropout frequency and taxonomic amplification bias are both reduced by using a PCR annealing temperature and cycle number on the low ends of the ranges currently used for the Leray‐FolDegenRev primers. We also report that tag jumps and erroneous sequences can be nearly eliminated with Begum filtering, at the cost of only a small rise in dropouts. We replicate published findings that uneven size distribution of input biomasses leads to greater dropout frequency and that OTU size is a poor predictor of species input biomass. Finally, we find no evidence for ‘tag‐biased’ PCR amplification.

To aid learning, reproducibility, and the design and testing of alternative metabarcoding pipelines, we provide our Illumina and input‐species sequence datasets, scripts, a spreadsheet for designing primer tags and a tutorial.
Differential price‐responsiveness of smoking behaviors among non‐Hispanic African Americans and non‐Hispanic whites in the United States
Authors: Wang Yingning , Max Wendy , Yao Tingting , Keeler Courtney , Sung Hai‐Yen 
Published: March 2021

AbstractBackground and aimsNon‐Hispanic African Americans (African Americans) smoke fewer cigarettes per day (CPD) and are more likely to be non‐daily smokers than non‐Hispanic whites (whites). Little is known about how changes in cigarette prices might contribute to these differences. This study aimed to measure the price‐responsiveness of smoking participation, non‐daily smoking among current smokers and smoking intensity among daily or non‐daily smokers for African Americans and compare the price‐responsiveness estimates with those for whites.DesignAnalysis of data from the 2009–14 National Adult Tobacco Surveys and cigarette price data from the Tax Burden on Tobacco report.SettingUnited States.ParticipantsA total of 19 232 African American and 197 939 white adults aged 18+.MeasurementsWe used a three‐part econometric model of cigarette demand to estimate the price‐responsiveness of smoking participation, daily versus non‐daily smoking and smoking intensity. The model controlled for secular variation, state‐level anti‐smoking sentiment and smoke‐free air laws and socio‐demographics.FindingsIn 2009–14, 20.2% of African Americans and 17.7% of whites identified as current smokers; 70.2% of African American smokers and 81.4% of white smokers smoked daily. The price elasticity of smoking participation was significant for whites at −0.16 [95% confidence interval (CI) = –0.23, –0.09], indicating that a 10% increase in prices would reduce smoking participation by 1.6%, but not statistically significant for African Americans, and this racial/ethnic differential price responsiveness was not statistically significant. The price elasticity of smoking intensity was statistically significant for African American daily smokers at −0.29 (95% CI = −0.42, –0.16), but not statistically significant for white daily smokers, and this racial/ethnic differential price‐responsiveness was statistically significant. The price elasticity of daily versus non‐daily smoking among current smokers, and the price elasticity of smoking intensity among non‐daily smokers were not statistically significant for either racial/ethnic group.ConclusionIn the United States, cigarette price increases may have stronger effects on decreasing daily smokers’ consumption among African Americans than among non‐Hispanic whites.