bluuebunny/crossref_metadata_2025_split huggingface dataset:
The HARPS search for southern extra-solar planets – XLV. Two Neptune mass planets orbiting HD 13808: a study of stellar activity modelling’s impact on planet detection
Authors: Ahrer E , Queloz D , Rajpaul V M , Ségransan D , Bouchy F , Hall R , Handley W , Lovis C , Mayor M , Mortier A , Pepe F , Thompson S , Udry S , Unger N 
Published: February 2021

ABSTRACT
We present a comprehensive analysis of 10 yr of HARPS radial velocities (RVs) of the K2V dwarf star HD 13808, which has previously been reported to host two unconfirmed planet candidates. We use the state-of-the-art nested sampling algorithm PolyChord to compare a wide variety of stellar activity models, including simple models exploiting linear correlations between RVs and stellar activity indicators, harmonic models for the activity signals, and a more sophisticated Gaussian process regression model. We show that the use of overly simplistic stellar activity models that are not well-motivated physically can lead to spurious ‘detections’ of planetary signals that are almost certainly not real. We also reveal some difficulties inherent in parameter and model inference in cases where multiple planetary signals may be present. Our study thus underlines the importance both of exploring a variety of competing models and of understanding the limitations and precision settings of one’s sampling algorithm. We also show that at least in the case of HD 13808, we always arrive at consistent conclusions about two particular signals present in the RV, regardless of the stellar activity model we adopt; these two signals correspond to the previously reported though unconfirmed planet candidate signals. Given the robustness and precision with which we can characterize these two signals, we deem them secure planet detections. In particular, we find two planets orbiting HD 13808 at distances of 0.11, 0.26 au with periods of 14.2, 53.8 d, and minimum masses of 11, 10 M⊕.
On the influence of Langmuir wave spectra on the spectra of electromagnetic waves generated in solar plasma with double plasma frequency
Authors: Kudryavtsev Igor V , Kaltman T I 
Published: February 2021

ABSTRACT
In this paper, we consider the spectral dependences of transverse electromagnetic waves generated in solar plasma at the coalescence of Langmuir waves. It is shown that different spectra of Langmuir waves lead to characteristic types of transversal electromagnetic wave spectra, what makes it possible to diagnose the features of the spectra of Langmuir waves generated in solar plasma.
Multicellular “hotspots” harbor high-grade potential in lower-grade gliomas
Authors: Kirby Alastair J , Lavrador José P , Bodi Istvan , Vergani Francesco , Bhangoo Ranjeev , Ashkan Keyoumars , Finnerty Gerald T 
Published: February 2021

AbstractBackgroundLower-grade gliomas may be indolent for many years before developing malignant behavior. The mechanisms underlying malignant progression remain unclear.MethodsWe collected blocks of live human brain tissue donated by people undergoing glioma resection. The tissue blocks extended through the peritumoral cortex and into the glioma. The living human brain tissue was cut into ex vivo brain slices and bathed in 5-aminolevulinic acid (5-ALA). High-grade glioma cells avidly take up 5-ALA and accumulate high levels of the fluorescent metabolite, Protoporphyrin IX (PpIX). We exploited the PpIX fluorescence emitted by higher-grade glioma cells to investigate the earliest stages of malignant progression in lower-grade gliomas.ResultsWe found sparsely distributed “hot-spots” of PpIX-positive cells in living lower-grade glioma tissue. Glioma cells and endothelial cells formed part of the PpIX hotspots. Glioma cells in PpIX hotspots were IDH1 mutant and expressed nestin suggesting they had acquired stem-like properties. Spatial analysis with 5-ALA-conjugated quantum dots indicated that these glioma cells replicated adjacent to blood vessels. PpIX hotspots were formed in the absence of angiogenesis.ConclusionOur data show that PpIX hotspots represent microdomains of cells with high-grade potential within lower-grade gliomas and identify locations where malignant progression could start.
PULMONARY NODULE DETECTION IN CHEST CT USING A DEEP LEARNING-BASED RECONSTRUCTION ALGORITHM
Authors: Franck C , Snoeckx A , Spinhoven M , El Addouli H , Nicolay S , Van Hoyweghen A , Deak P , Zanca F 
Published: February 2021

Abstract
This study’s aim was to assess whether deep learning image reconstruction (DLIR) techniques are non-inferior to ASIR-V for the clinical task of pulmonary nodule detection in chest computed tomography. Up to 6 (range 3–6, mean 4.2) artificial lung nodules (diameter: 3, 5, 8 mm; density: −800, −630, +100 HU) were inserted at different locations in the Kyoto Kagaku Lungman phantom. In total, 16 configurations (10 abnormal, 6 normal) were scanned at 7.6, 3, 1.6 and 0.38 mGy CTDIvol (respectively 0, 60, 80 and 95% dose reduction). Images were reconstructed using 50% ASIR-V and a deep learning-based algorithm with low (DL-L), medium (DL-M) and high (DL-H) strength. Four chest radiologists evaluated 256 series by locating and scoring nodules on a five-point scale. No statistically significant difference was found among the reconstruction algorithms (p = 0.987, average across readers AUC: 0.555, 0.561, 0.557, 0.558 for ASIR-V, DL-L, DL-M, DL-H).
Root carbon and nutrient homeostasis determines downy oak sapling survival and recovery from drought
Authors: Ouyang Sheng-Nan , Gessler Arthur , Saurer Matthias , Hagedorn Frank , Gao De-Cai , Wang Xiao-Yu , Schaub Marcus , Li Mai-He , Shen Wei-Jun , Schönbeck Leonie 
Published: February 2021

Abstract
The role of carbon (C) and nutrient uptake, allocation, storage and especially their interactions in survival and recovery of trees under increased frequencies and intensities of drought events is not well understood. A full factorial experiment with four soil water content regimes ranging from extreme drought to well-watered conditions and two fertilization levels was carried out. We aimed to investigate whether nutrient addition mitigates drought effects on downy oak (Quercus pubescens Willd.) and whether storage pools of non-structural carbohydrates (NSC) are modified to enhance survival after 2.5 years of drought and recovery after drought relief. Physiological traits, such as photosynthesis, predawn leaf water potential as well as tissue biomass together with pools and dynamics of NSC and nutrients at the whole-tree level were investigated. Our results showed that fertilization played a minor role in saplings’ physiological processes to cope with drought and drought relief, but reduced sapling mortality during extreme drought. Irrespective of nutrient supply, Q. pubescens showed increased soluble sugar concentration in all tissues with increasing drought intensity, mostly because of starch degradation. After 28 days of drought relief, tissue sugar concentrations decreased, reaching comparable values to those of well-watered plants. Only during the recovery process from extreme drought, root NSC concentration strongly declined, leading to an almost complete NSC depletion after 28 days of rewetting, simultaneously with new leaves flushing. These findings suggest that extreme drought can lead to root C exhaustion. After drought relief, the repair and regrowth of organs can even exacerbate the root C depletion. We concluded that under future climate conditions with repeated drought events, the insufficient and lagged C replenishment in roots might eventually lead to C starvation and further mortality.
How to decide which COVID-19 patient with myocardial infarction to send to the Cath Lab? - A case series of COVID-19 patients with myocardial infarction
Authors: Simova Iana , Nikolov Denis , Dimitrov Nikolay , Kornovski Vladimir , Tomova Vesela , Vekov Toni , Krasnaliev Yordan 
Published: February 2021

AbstractINTRODUCTIONThe Coronavirus pandemic has hit the world with its vast contagiousness, high morbidity, and mortality. Apart from the direct damage to the lung tissue, the corona virus infection is able to predispose patients to thrombotic disease, thus causing cerebral or coronary incidents.AIMSThe aim of this study was to find a clinical or laboratory parameter, that would help in distinguishing between COVID-19 patients with myocardial infarction (MI), who have an infarct-related artery (IRA) and therefore, require immediate revascularization, and those, who have no IRA.METHODSThis was a single-center, observational study of 10 consecutive patients with COVID-19, who were admitted with confirmed MI.RESULTSIn our study group the mean age was 67.5 ± 8.3 years, half of the patients were female; all of them had arterial hypertension; 8 patients (80%) had dyslipidemy; 4 (40%) had diabetes. 30% of the patients with MI did not have an IRA, and did not require pPCI. Patients with MI and IRA had significantly higher hsTrI values (48.9 ± 43.2 vs 0.6 ± 0.7, p=0.007) and exclusively typical chest pain 100% vs 0%, p=0.007), compared to patients with MI without an IRA. The ECG changes had only marginal statistical significance. Our results suggest that using a higher cut-off value for hsTrI (>7.5 times upper reference range) increases the specificity and positive predictive value for diagnosing a MI with the presence of IRA and need for pPCI, to 100%CONCLUSIONIn our analysis we confirm that a higher cut-off value for hsTrI helps distinguish between COVID patients with MI, who have IRA and therefore, require immediate revascularization, compared to those, who have no IRA.
The protective association between statins use and adverse outcomes among COVID-19 patients: a systematic review and meta-analysis
Authors: Chow Ronald , Im James , Chiu Nicholas , Chiu Leonard , Aggarwal Rahul , Lee Jihui , Choi Young-Geun , Prsic Elizabeth Horn , Shin Hyun Joon 
Published: February 2021

ABSTRACTIntroductionStatins may reduce a cytokine storm, which has been hypothesized as a possible mechanism of severe COVID-19 pneumonia. The aim of this study was to conduct a systematic review and meta-analysis to report on adverse outcomes among COVID-19 patients by statin usage.MethodsLiteratures were searched from January 2019 to December 2020 to identify studies that reported the association between statin usage and adverse outcomes, including mortality, ICU admissions, and mechanical ventilation. Studies were meta-analyzed for mortality by the subgroups of ICU status and statin usage before and after COVID-19 hospitalization. Studies reporting an odds ratio (OR) and hazard ratio (HR) were analyzed separately.ResultsThirteen cohorts, reporting on 110,078 patients, were included in this meta-analysis. Individuals who used statins before their COVID-19 hospitalization showed a similar risk of mortality, compared to those who did not use statins (HR 0.80, 95% CI: 0.50, 1.28; OR 0.62, 95% CI: 0.38, 1.03). Patients who were administered statins after their COVID-19 diagnosis were at a lower risk of mortality (HR 0.53, 95% CI: 0.46, 0.61; OR 0.57, 95% CI: 0.43, 0.75). The use of statins did not reduce the mortality of COVID-19 patients admitted to the ICU (OR 0.65; 95% CI: 0.26, 1.64). Among non-ICU patients, statin users were at a lower risk of mortality relative to non-statin users (HR 0.53, 95% CI: 0.46, 0.62; OR 0.64, 95% CI: 0.46, 0.88).ConclusionPatients administered statins after COVID-19 diagnosis or non-ICU admitted patients were at lower risk of mortality relative to non-statin users.
Investigating the effects of consumer characteristics with respect to brand knowledge and product involvement on brand alliance evaluation
Authors: Singh Pankaj , Ahmad Anees , Prakash Gyan , Kushwah Prabhat Kumar Singh 
Published: February 2021

PurposeThe purpose of this paper is to take the neglected influencing factors in brand alliance research into account based on consumer characteristics theory and discuss the influencing factors' interactive effects on brand alliance.Design/methodology/approachBased on the theory of consumer characteristics and the S&R model of brand alliance, an experimental design was conducted to examine the relationship among the various variables and moderators, which can test the changes of the dependent variables by controlling and manipulating one or more single variables. The sample includes 400 college students.FindingsThe results demonstrate that brand knowledge positively moderates the relationship between brand equity and consumer brand alliance, but not significantly affect the relationship between alliance evaluation and joint fit; in contrast, product involvement individually plays a positive moderating role on the relationship between joint fit, brand equity and consumer brand alliance evaluation.Originality/valueTwo consumer characteristic, brand knowledge and product involvement moderate the relationship between brand equity, joint fit and consumer brand alliance evaluation. Several empirical studies on brand alliance have documented mostly positive effects of brand alliance on consumer brand evaluations. Two important consumer characteristics' effect on brand alliance evaluation, brand knowledge and product involvement, were testified to expand the scope of influential factors of brand alliance evaluation on the basis of consumers' characteristic theory.
Measuring community disaster resilience using Q-methods: a physical resilience perspective
Authors: Tariq Hisham , Pathirage Chaminda , Fernando Terrence 
Published: February 2021

PurposeDecision-makers, practitioners and community members have a need to assess the disaster resilience of their communities and to understand their own capacities in disaster situations. There is a lack of consensus among researchers as to what resilience means and how it can be measured. This paper proposes a novel technique to achieve consensus among stakeholders on definitions, objectives and indicators for measuring a key dimension of community disaster resilience (CDR), physical infrastructure (PI).Design/methodology/approachThis study uses a five-step approach utilizing Q-methods to contextualize a resilience index for PI. Interviews, focus groups and Q-sorting workshops were conducted to develop a tool that ranked measures according to stakeholder preference. A total of 84 participants took part in the workshops across four countries (United Kingdom, Malaysia, Pakistan and Sri Lanka).FindingsThe initial set of 317 measures was reduced to 128 and divided into the three community capacities of anticipatory, absorptive and restorative. The physical infrastructure capacity assessment tool (PI-CAT) was then finalized to have 38 indicators that were also ranked in order of importance by the participants.Practical implicationsThe PI-CAT can be useful for local governments and communities to measure their own resilience. The tool allows stakeholders to be confident that the metrics being used are ones that are relevant, important and meet their requirements.Originality/valueThe Q-method approach helps stakeholders to develop and use a community capacity assessment tool that is appropriate for their context. The PI-CAT can be used to identify effective investments that will enhance CDR.
Muddying the waters: when does short selling become market manipulation?
Authors: Durston Gregory 
Published: February 2021

Purpose
This paper aims to consider “spoofing”, “layering” and “short reports” in the context of market manipulation and, in particular, a recent controversy involving a short-selling attack on a major UK listed company that was considered by the High Court.

Design/methodology/approach
The very demanding legal and evidential prerequisites and practical difficulties, involved in bringing both criminal and regulatory actions in such cases are identified and discussed, as is the role of the Financial Conduct Authority.

Findings
These challenges help explain why so few actions of this type are brought.

Originality/value
This is the first paper to consider the implications of Burford Capital Limited v London Stock Exchange Plc [2020] EWHC 1183 (Comm).
Distributed leadership and nurses’ job satisfaction: a survey
Authors: Sammut Roberta , Briffa Benjamin , Curtis Elizabeth A. 
Published: February 2021

Purpose
The purpose of this paper is to explore the relationship between perceived distributed leadership and job satisfaction among nurses. Leadership is central to improving quality care. Reports following investigations of poor care standards, identified inadequate leadership as a contributory factor and called for a new kind of leadership. One alternative is distributed leadership. Evidence suggests associations between leadership and job satisfaction but, there is a paucity of research examining associations between distributed leadership and job satisfaction: the purpose of this study was to address this gap.

Design/methodology/approach
A cross-sectional survey design was used and data collected via questionnaires. Using census sampling, 350 nurses in a hospital in Malta were selected. A response rate of 50% (n = 176) was achieved. Data were analysed using Spearman’s correlation coefficient and multiple regression. Ethical approval was obtained from relevant committees/individuals.

Findings
Results indicated a moderate application of perceived distributed leadership and application of all components of distributed leadership could be improved. Nurses were neither satisfied nor dissatisfied with their jobs. Correlation analysis showed a positive relationship between distributed leadership and job satisfaction. Multiple regression showed that commitment and participative decision-making were major predictors of job satisfaction while supervision by managers had a negative effect.

Practical implications
Improving distributed leadership is a priority in the nursing profession.

Originality/value
To the best of the authors’ knowledge, this study is the first to show that distributed leadership has a positive effect on job satisfaction among nurses. Supervision, a constituent of distributed leadership, was associated with reduced job satisfaction, therefore reducing this is paramount.
Impact of using ARCS model and problem-based leaning on human interaction with robot and motivation
Authors: Hsia Chih-Hsien , Lai Chin-Feng , Su Yu-Sheng 
Published: February 2021

PurposeThe purpose of this study, we present a robot used in education. Influenced by the epoch of revolutionary digital technology, the methodology of education has gone boundless. The robot programming sustainability and ability to solve problems is one an important skill that coding students require to learn programming. This educational have been integrated into curriculum instruction in clubs.Design/methodology/approachRobotics education has been regarded as a potential approach to enhance students' Science, technology, engineering, and mathematics learning competencies. The popular platform of robots diversifies educational practices by its advantages of reorganizational and logical forms. In this paper, we focus on the effects of applying blended instructional approaches to robot education on students' programming sustainability and ability.FindingsThe students of department of mechanical engineering at the University in Taipei city, who participate elective educational robot courses, prove through surveys that the problem-based leaning method with robot programming can effectively enhance students' interests and learning motivations in learning new knowledge and promote students' designing skills for a sustainable society.Originality/valueIn this paper, the authors focus on the effects of applying blended instructional approaches to robot education on students' programming sustainability and ability.
Obstetric outcomes for twins from different conception methods – A multicenter cross‐sectional study from China
Authors: Jiang Fang , Gao Jinsong , He Jing , Tang Yabing , Cao Yinli , Wang Xietong , Liu Xiaowei , Wang Tianyun , Liu Xinghui , Sun Jingxia , Zhong Mei , Liu Xiaohong , Liao Shixiu , Liu Caixia , Yang Jinying 
Published: February 2021

AbstractIntroductionThe effects of assisted reproductive technology on the outcomes of twin pregnancies are controversial. Therefore, the purpose of this study was to compare the maternal and perinatal outcomes of twin pregnancies conceived spontaneously and those conceived by assisted reproductive technology.Material and methodsThis was a cross‐sectional study performed at Peking Union Medical College Hospital (PUMCH). Data on twin pregnancies (conceived spontaneously and by in vitro fertilization [IVF]/intracytoplasmic sperm injection [ICSI]) were obtained from the National Birth Registry of China for the period between 1 October 2016, and 30 September 2017. The primary obstetric outcomes were compared between twin pregnancies conceived by different methods. Logistic regression analysis with 95% confidence intervals (95% CI) was used for the multivariate analysis.ResultsA total of 3270 twin pregnancies (2003 and 1209 conceived spontaneously and by IVF/ICSI, respectively) were identified. The proportion of twin pregnancies among all pregnancies was 3.4% (3332/97 278). Multiple regression analysis indicated that the incidences of gestational diabetes mellitus (adjusted odds ratio [AOR] = 1.42, 95% CI 1.10–1.83, p = 0.007), preterm premature rupture of membranes (AOR = 1.65, 95% CI 1.21–2.25, p = 0.002), placenta accreta spectrum (AOR = 2.12, 95% CI 1.42–3.17, p < 0.001) and postpartum hemorrhage (AOR = 1.38, 95% CI 1.02–1.86, p = 0.037) were significantly higher in the IVF/ICSI group than in the natural pregnancy group. Multivariate analysis also revealed that conception mode was not an independent risk factor for neonate outcomes.ConclusionsIn twin pregnancies, IVF/ICSI is independently associated with multiple maternal complications, including gestational diabetes mellitus, preterm premature rupture of membranes and placenta accreta spectrum compared with spontaneous conception, although potential residual confounders due to indications for assisted reproductive technology exist.
Health‐related quality of life maintained over time in patients with relapsed or refractory multiple myeloma treated with daratumumab in combination with bortezomib and dexamethasone: results from the phase III CASTOR trial
Authors: Hungria Vania , Beksac Meral , Weisel Katja C. , Nooka Ajay K. , Masszi Tamas , Spicka Ivan , Munder Markus , Mateos María‐Victoria , Mark Tomer M. , Qi Ming , Qin Xiang , Fastenau John , Spencer Andrew , Sonneveld Pieter , Garvin Wendy , Renaud Thomas , Gries Katharine S. 
Published: February 2021

SummaryIn the phase III CASTOR trial, daratumumab, bortezomib and dexamethasone (D‐Vd) significantly extended progression‐free survival compared with bortezomib and dexamethasone (Vd) alone in patients with relapsed/refractory multiple myeloma (RRMM). Here, we present patient‐reported outcomes (PROs) from the CASTOR trial. PROs were assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30‐item (EORTC QLQ‐C30) and the EuroQol 5‐dimensional descriptive system questionnaire. Treatment effects through Cycle 8 were measured by a repeated measures mixed‐effects model. After Cycle 8, PROs were only collected for patients in the D‐Vd group who continued on daratumumab monotherapy. Compliance rates for PRO assessments were high and similar between treatment groups. Mean changes from baseline were generally similar between treatment groups for EORTC QLQ‐C30 global health status (GHS), functioning and symptoms, and did not exceed 10 points for either treatment group. Subgroup analyses were consistent with the results observed in the overall population. There was no change in patients' health‐related quality of life for the first eight cycles of therapy; thereafter, patients treated with daratumumab over the long‐term reported improvements in GHS and pain. These results complement the significant clinical benefits observed with D‐Vd in patients with RRMM and support its use in this patient population.