bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Study on PAHs in the surface soil of the region around Qinghai Lake in the Tibet plateau: evaluation of distribution characteristics, sources and ecological risks
Authors: Zhang Zhongdi , Zhu Yadi , Shao Tianjie , Wang Ruojin , Chen Zongyan , Wei Peiru , Xu Zhiping , Li Dongze , Fu Lijuan , Wang Feier 
Published: March 2021

Abstract
In order to evaluate the pollution and ecological risks of polycyclic aromatic hydrocarbons (PAHs) in the soil around the Qinghai Lake, 89 surface soil samples were collected in May 2019. After ultrasonic extraction and purification of silica gel-alumina-anhydrous Na2SO4 chromatographic column, GC-MS was used to test and analyze 16 kinds of monomer PAHs under priority control of USEPA in the samples, so as to study the distribution characteristics, sources and ecological risks. The results are shown as follows: (1) The total amount of 16 kinds of PAHs in the soil of the study area was 169.00 ∼ 638.94 μg·kg−1 , with an average of 318.37 μg·kg−1. The PAHs are dominated by dicyclic and tricyclic aromatic hydrocarbons, accounting for 40.89%∼70.73% of the mass fraction of PAHs, with an average of 49.22%, and phenanthrene accounts for the highest mass fraction. (2) The percentage of sampling points that exceeded the standard (200 μg·kg−1, which represents the upper limit of ‘no pollution’) was 87.6%, dominated by mild pollution(200 ∼ 600 μg·kg−1). The soil pollution in the west and south of the Qinghai Lake is relatively lighter than the north of the Qinghai Lake. (3) The toxicity equivalent concentration of TEQBaP for pyrene ranged from 8.19 to 42.35 μg·kg−1, with an average of 18.82 μg·kg−1. The ecological risk assessment results based on toxicity equivalent concentration and risk quality standard method showed that there was a low risk of PAHs in soil in this study area, and only a few areas exceeding the target reference value, mainly concentrated in the northern area of Qinghai Lake. (4) The results of source analysis by ratio method and principal component analysis method show that PAHs in the surface soil of the region around the Qinghai Lake come mainly from the combustion of oil and biomass.
Enhancing single photon emission through quasi-bound states in the continuum of monolithic hexagonal boron nitride metasurface
Authors: Cao Shun , Jin Yi , Dong Hongguang , Guo Tingbiao , He Jinlong , He Sailing 
Published: March 2021

Abstract
A patterned structure of monolithic hexagonal boron nitride (hBN) on a glass substrate, which can enhance the emission of the embedded single photon emitters (SPEs), is useful for onchip single-photon sources of high-quality. Here, we design and demonstrate a monolithic hBN metasurface with quasi-bound states in the continuum mode at emission wavelength with ultrahigh Q values to enhance fluorescence emission of SPEs in hBN. Because of ultrahigh electric field enhancement inside the proposed hBN metasurface, an ultrahigh Purcell factor (3.3 × 104) is achieved. In addition, the Purcell factor can also be strongly enhanced in most part of the hBN structure, which makes the hBN metasurface suitable for e.g. monolithic quantum photonics.
Crop photoperiodism model 2.0 for the flowering time of sorghum and rice that includes daily changes in sunrise and sunset times and temperature acclimation
Authors: Clerget B , Sidibe M , Bueno C S , Grenier C , Kawakata T , Domingo A J , Layaoen H L , Gutiérrez-Palacios N D , Bernal J H , Trouche G , Chantereau J 
Published: March 2021

Abstract

Background and Aims
Daylength determines flowering dates. However, questions remain regarding flowering dates in the natural environment, such as the synchronous flowering of plants sown simultaneously at highly contrasting latitudes. The daily change in sunrise and sunset times is the cue for the flowering of trees and for the synchronization of moulting in birds at the equator. Sunrise and sunset also synchronize the cell circadian clock, which is involved in the regulation of flowering. The goal of this study was to update the photoperiodism model with knowledge acquired since its conception.

Methods
A large dataset was gathered, including four 2-year series of monthly sowings of 28 sorghum varieties in Mali and two 1-year series of monthly sowings of eight rice varieties in the Philippines to compare with previously published monthly sowings in Japan and Malaysia, and data from sorghum breeders in France, Nicaragua and Colombia. An additive linear model of the duration in days to panicle initiation (PI) and flowering time using daylength and daily changes in sunrise and sunset times was implemented.

Key Results
Simultaneous with the phyllochron, the duration to PI of field crops acclimated to the mean temperature at seedling emergence within the usual range of mean cropping temperatures. A unique additive linear model combining daylength and daily changes in sunrise and sunset hours was accurately fitted for any type of response in the duration to PI to the sowing date without any temperature input. Once calibrated on a complete and an incomplete monthly sowing series at two tropical latitudes, the model accurately predicted the duration to PI of the concerned varieties from the equatorial to the temperate zone.

Conclusions
Including the daily changes in sunrise and sunset times in the updated photoperiodism model largely improved its accuracy at the latitude of each experiment. More research is needed to ascertain its multi-latitudinal accuracy, especially at latitudes close to the equator.
Impact of Trade on Inequality: New Evidence of What, When, and Where
Authors: Siddique Abu Bakkar 
Published: March 2021

Abstract
The relationship between trade and inequality is complex, and the existing literature concludes that the impacts of trade on inequality are ambiguous. This article addresses this ambiguity and presents robust evidence that the effects of trade on inequality depend on economic development, when it occurred in recent decades, and their various measures. It proposes a novel identification strategy to solve for endogeneity problem in the literature by using trade as predicted by a gravity equation as an instrument for actual trade. It estimates the effect of both trade policies and trade volumes on inequality measured both before and after taxes and transfers. This article takes advantage of large and long panel data by conducting cross-examinations by economic development and economic history. The results show that international trade exacerbates inequality in the pre-taxes, but the effects disappear after taxes and transfers are adjusted; thus, it supports the compensation hypothesis. It increases inequality in rich economies while reducing it in poor economies, which confirms the standard Stolper and Samuelson theorem. Post-1991 trade experience was inequality increasing but pre-1991 trade was inequality decreasing; however, trade opening by reducing regulations, taxes, and tariffs was always inequality increasing. (JEL codes: D63, P33, and F63)
Cardiogenic shock in the context of newly diagnosed anomalous origin of the right coronary artery originating from the pulmonary artery: a case report
Authors: Kappel Coralea , Chow Justin , Ahmed Zeeshan , Schwalm Jon-David , Amin Faizan 
Published: March 2021

Abstract

Background
Anomalous right coronary artery (RCA) from the pulmonary artery (ARCAPA) is a rare congenital heart abnormality with varying clinical presentations, for which multiple imaging modalities are often required for diagnosis.

Case summary
We present a case of a 76-year-old female presenting with 2 weeks of palpitations and shortness of breath who was found to be in rapid atrial fibrillation (AF) with congestive heart failure. Despite initial medical management, the patient developed cardiogenic shock with anuric renal failure. Emergent right and left heart catheterization did not demonstrate any significant obstructive coronary artery disease but showed severe right ventricular (RV) failure and raised the possibility of an ARCAPA. This diagnosis was further corroborated by findings on a subsequent transoesophageal echocardiogram. In view of profound decline and limited anticipated improvement, the patient ultimately decided to pursue comfort measures in a hospice setting.

Discussion
We postulate that the underlying aetiology of our patient’s shock state was multifactorial, notably progressive RCA-territory ischaemia and RV failure, sepsis, and new-onset uncontrolled AF. In adults, unrecognized congenital heart disease can uncommonly cause cardiogenic shock. In our case, echocardiography and invasive angiography were integrated for the diagnosis of ARCAPA given the clinical circumstances that limited the use of cardiac computed tomography angiography.
Autoimmune hypophysitis as a cause of adrenocorticotropic hormone deficiency in pulmonary arterial hypertension: a case report
Authors: Ichihara Genki , Kataoka Masaharu , Katsumata Yoshinori , Fukuda Keiichi 
Published: March 2021

Abstract

Background
Severe pulmonary arterial hypertension (PAH) is generally treated with multiple PAH-specific vasodilators. If these agents are unsuccessful, additional treatment options are scarce, and the prognosis is poor due to right-sided heart failure. Some of these severe cases are also accompanied by endocrinological side effects. The most common side effect of prostacyclin is thyroid dysfunction, but in very few cases, adrenocorticotropic hormone (ACTH) deficiency may occur.

Case summary
A 35-year-old woman was diagnosed with hereditary PAH 2 years ago. Since her mean pulmonary arterial pressure was high, combination therapy of vasodilators, including prostacyclin, was introduced. Several months later, she was hospitalized with a persistent fever. Laboratory tests showed no findings suggestive of infection. However, hypereosinophilia and decreased secretion of ACTH and cortisol were noted, which led to the diagnosis of ACTH deficiency. A multimodal diagnostic approach, including pituitary magnetic resonance imaging and axillary lymph node biopsy, indicated that the aetiology of the ACTH deficiency was likely autoimmune hypophysitis. She was treated with hydrocortisone supplementation, which significantly relieved her condition.

Discussion
Endocrinological side effects in PAH patients using prostacyclin should be carefully addressed. If right-sided heart failure worsens during the administration of prostacyclin, it is essential to determine whether it is due to progression of pulmonary hypertension or endocrinological side effects. Careful diagnosis and treatment are important for managing the haemodynamics and symptoms of PAH patients given prostacyclin.
Are treatment effect assumptions in orthodontic studies overoptimistic?
Authors: Seehra Jadbinder , Stonehouse-Smith Daniel , Cobourne Martyn T , Tsagris Michail , Pandis Nikolaos 
Published: March 2021

Summary

Background
At the clinical trial design stage, assumptions regarding the treatment effects to be detected should be appropriate so that the required sample size can be calculated. There is evidence in the medical literature that sample size assumption can be overoptimistic. The aim of this study was to compare the distribution of the assumed effects versus that of the observed effects as a proxy for overoptimistic treatment effect assumptions at the study design stage.

Materials and method
Systematic reviews (SRs) published between 1 January 2010 and 31 December 2019 containing at least one meta-analysis on continuous outcomes were identified electronically. SR and primary study level characteristics were extracted from the SRs and the individual trials. Details on the sample size calculation process and assumptions and the observed treatment effects were extracted.

Results
Eighty-five SRs with meta-analysis containing 347 primary trials were included. The median number of SR authors was 5 (interquartile range: 4–7). At the primary study level, the majority were single centre (78.1%), utilized a parallel design (52%), and rated as an unclear/moderate level of risk of bias (34.3%). A sample size was described in only 31.7% (110/347) of studies. From this cohort of 110 studies, in only 37 studies was the assumed clinical difference that the study was designed to detect reported (37/110). The assumed treatment effect was recalculated for the remaining 73 studies (73/110). The one-sided exact signed rank test showed a significant difference between the assumed and observed treatment effects (P &lt; 0.001) suggesting greater values for the assumed effect sizes.

Conclusions
Careful consideration of the assumptions at the design stage of orthodontic studies are necessary in order to reduce the unreliability of clinical study results and research waste.
Online prevention programmes for university students: stakeholder perspectives from six European countries
Authors: Irish Madeleine , Kuso Stefanie , Simek Monika , Zeiler Michael , Potterton Rachel , Musiat Peter , Nitsch Martina , Wagner Gudrun , Karwautz Andreas , Bolinski Felix , Karyotaki Eirini , Rovira Carla Soler , Etchemendy Ernestina , Herrero Rocio , Mira Adriana , Cormo Giulia , Baños Rosa , Garcia-Palacios Azucena , Ebert David D , Franke Marvin , Zarski Anna-Carlotta , Weisel Kiona , Berger Thomas , Dey Michelle , Schaub Michael P , Jacobi Corinna , Botella Cristina , Oliver Elia , Gordon Gemma , Spencer Lucy , Waldherr Karin , Schmidt Ulrike 
Published: March 2021

Abstract

Background
Students beginning university are at a heightened risk for developing mental health disorders. Online prevention and early intervention programmes targeting mental health have the potential to reduce this risk, however, previous research has shown uptake to be rather poor. Understanding university stakeholders’ (e.g. governing level and delivery staff [DS] and students) views and attitudes towards such online prevention programmes could help with their development, implementation and dissemination within university settings.

Methods
Semi-structured interviews, focus groups and online surveys were completed with staff at a governing level, university students and DS (i.e. student health or teaching staff) from six European countries. They were asked about their experiences with, and needs and attitudes towards, online prevention programmes, as well as the factors that influence the translation of these programmes into real-world settings. Results were analyzed using thematic analysis.

Results
Participating stakeholders knew little about online prevention programmes for university settings; however, they viewed them as acceptable. The main themes to emerge were the basic conditions and content of the programmes, the awareness and engagement, the resources needed, the usability and the responsibility and ongoing efforts to increase reach.

Conclusions
Overall, although these stakeholders had little knowledge about online prevention programmes, they were open to the idea of introducing them. They could see the potential benefits that these programmes might bring to a university setting as a whole and the individual students and staff members.
Synteny-Based Genome Assembly for 16 Species ofHeliconiusButterflies, and an Assessment of Structural Variation across the Genus
Authors: Seixas Fernando A , Edelman Nathaniel B , Mallet James 
Published: March 2021

AbstractHeliconius butterflies (Lepidoptera: Nymphalidae) are a group of 48 neotropical species widely studied in evolutionary research. Despite the wealth of genomic data generated in past years, chromosomal level genome assemblies currently exist for only two species, Heliconius melpomene and Heliconius erato, each a representative of one of the two major clades of the genus. Here, we use these reference genomes to improve the contiguity of previously published draft genome assemblies of 16 Heliconius species. Using a reference-assisted scaffolding approach, we place and order the scaffolds of these genomes onto chromosomes, resulting in 95.7–99.9% of their genomes anchored to chromosomes. Genome sizes are somewhat variable among species (270–422 Mb) and in one small group of species (Heliconius hecale, Heliconius elevatus, and Heliconius pardalinus) expansions in genome size are driven mainly by repetitive sequences that map to four small regions in the H. melpomene reference genome. Genes from these repeat regions show an increase in exon copy number, an absence of internal stop codons, evidence of constraint on nonsynonymous changes, and increased expression, all of which suggest that at least some of the extra copies are functional. Finally, we conducted a systematic search for inversions and identified five moderately large inversions fixed between the two major Heliconius clades. We infer that one of these inversions was transferred by introgression between the lineages leading to the erato/sara and burneyi/doris clades. These reference-guided assemblies represent a major improvement in Heliconius genomic resources that enable further genetic and evolutionary discoveries in this genus.
The timing of human adaptation from Neanderthal introgression
Authors: Yair Sivan , Lee Kristin M , Coop Graham 
Published: March 2021

Abstract
Admixture has the potential to facilitate adaptation by providing alleles that are immediately adaptive in a new environment or by simply increasing the long-term reservoir of genetic diversity for future adaptation. A growing number of cases of adaptive introgression are being identified in species across the tree of life, however the timing of selection, and therefore the importance of the different evolutionary roles of admixture, is typically unknown. Here, we investigate the spatio-temporal history of selection favoring Neanderthal-introgressed alleles in modern human populations. Using both ancient and present-day samples of modern humans, we integrate the known demographic history of populations, namely population divergence and migration, with tests for selection. We model how a sweep placed along different branches of an admixture graph acts to modify the variance and covariance in neutral allele frequencies among populations at linked loci. Using a method based on this model of allele frequencies, we study previously identified cases of adaptive Neanderthal introgression. From these, we identify cases in which Neanderthal-introgressed alleles were quickly beneficial and other cases in which they persisted at low frequency for some time. For some of the alleles that persisted at low frequency, we show that selection likely independently favored them later on in geographically separated populations. Our work highlights how admixture with ancient hominins has contributed to modern human adaptation and contextualizes observed levels of Neanderthal ancestry in present-day and ancient samples.
Modeling Hessian-vector products in nonlinear optimization: new Hessian-free methods
Authors: Song L , Vicente L N 
Published: March 2021

Abstract
In this paper we suggest two ways of calculating interpolation models for unconstrained smooth nonlinear optimization when Hessian-vector products are available. The main idea is to interpolate the objective function using a quadratic on a set of points around the current one, and concurrently using the curvature information from products of the Hessian times appropriate vectors, possibly defined by the interpolating points. These enriched interpolating conditions then form an affine space of model Hessians or model Newton directions, from which a particular one can be computed once an equilibrium or least secant principle is defined. A first approach consists of recovering the Hessian matrix satisfying the enriched interpolating conditions, from which then a Newton direction model can be computed. In a second approach we pose the recovery problem directly in the Newton direction. These techniques can lead to a significant reduction in the overall number of Hessian-vector products when compared to the inexact or truncated Newton method, although simple implementations may pay a cost in the number of function evaluations and the dense linear algebra involved poses a scalability challenge.
Risk Estimation of Sexual Transmission of Zika Virus—United States, 2016–2017
Authors: Major Chelsea G , Paz-Bailey Gabriela , Hills Susan L , Rodriguez Dania M , Biggerstaff Brad J , Johansson Michael 
Published: March 2021

Abstract

Background
Zika virus (ZIKV) can be transmitted sexually but the risk of sexual transmission remains unknown. Most evidence of sexual transmission is from partners of infected travelers returning from areas with ZIKV circulation.

Methods
We used data from the US national arboviral disease surveillance system on travel- and sexually acquired ZIKV disease cases during 2016–2017 to develop individual-level simulations for estimating risk of male-to-female, male-to-male, and female-to-male sexual transmission of ZIKV via vaginal and/or anal intercourse. We specified parametric distributions to characterize individual-level variability of parameters for ZIKV persistence and sexual behaviors.

Results
Using ZIKV RNA persistence in semen/vaginal fluids to approximate infectiousness duration, male-to-male transmission had the highest estimated probability (1.3% [95% confidence interval, CI, .4%–6.0%] per anal sex act), followed by male-to-female and female-to-male transmission (0.4% [95% CI, .3%–.6%] per vaginal/anal sex act and 0.1% [95% CI, 0%–.8%] per vaginal sex act, respectively). Models using viral isolation in semen vs RNA detection to approximate infectiousness duration predicted greater risk of sexual transmission.

Conclusions
While likely insufficient to maintain sustained transmission, the estimated risk of ZIKV transmission through unprotected sex is not trivial and is especially important for pregnant women, as ZIKV infection can cause severe congenital disorders.
On the relationship between Type Ia supernova luminosity and host-galaxy properties
Authors: Murakami Yukei S , Stahl Benjamin E , Zhang Keto D , Chu Matthew R , McGinness Emma C , Patra Kishore C , Filippenko Alexei V 
Published: March 2021

ABSTRACT
A string of recent studies has debated the exact form and physical origin of an evolutionary trend between the peak luminosity of Type Ia supernovae (SNe Ia) and the properties of the galaxies that host them. We shed new light on the discussion by presenting an analysis of ∼200 low-redshift SNe Ia in which we measure the separation of Hubble residuals (HR; as probes of luminosity) between two host-galaxy morphological types. We show that this separation can test the predictions made by recently proposed models, using an independently and empirically determined distribution of each morphological type in host-property space. Our results are partially consistent with the new HR–age slope, but we find significant scatter in the predictions from different galaxy catalogues. The inconsistency in age illuminates an issue in the current debate that was not obvious in the long-discussed mass models: HR–host-property models are strongly dependent on the methods employed to determine galaxy properties. While our results demonstrate the difficulty in constructing a universal model for age as a proxy for host environment, our results indeed identify evolutionary trends between mass, age, morphology, and HR values, encouraging (or requiring, if such trends are to be accounted for in cosmological studies) further investigation.