bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of diagnostic test procedures for SARS‐CoV‐2 using latent class models
Authors: Stærk‐Østergaard Jacob , Kirkeby Carsten , Christiansen Lasse E. , Andersen Michael A. , Møller Camilla H. , Voldstedlund Marianne , Denwood Matthew J. 
Published: June 2022

AbstractPolymerase chain reaction (PCR) and antigen tests have been used extensively for screening during the severe acute respiratory syndrome coronavirus 2 pandemics. However, the real‐world sensitivity and specificity of the two testing procedures in the field have not yet been estimated without assuming that the PCR constitutes a gold standard test. We use latent class models to estimate the in situ performance of both tests using data from the Danish national registries. We find that the specificity of both tests is very high (>99.7%), while the sensitivities are 95.7% (95% confidence interval [CI]: 92.8%–98.4%) and 53.8% (95% CI: 49.8%–57.9%) for the PCR and antigen tests, respectively. These findings have implications for the use of confirmatory PCR tests following a positive antigen test result: we estimate that serial testing is counterproductive at higher prevalence levels.
Free and glycosylated aroma compounds in grapes monitored by solid‐liquid extraction and dispersive liquid‐liquid microextraction combined with gas chromatography‐mass spectrometry
Authors: Oller‐Ruiz Ainhoa , Viñas Pilar , Hernández‐Córdoba Manuel , Fenoll José , Garrido Isabel , Campillo Natalia 
Published: June 2022

Fifteen aroma compounds have been determined in their free and glycosylated forms in grapes using dispersive liquid‐liquid microextraction with gas chromatography‐mass spectrometry. The sample treatment includes a previous solid‐liquid extraction stage and subsequent parallel microextraction approaches to preconcentrate total aroma content and the free fraction. Thus, the extraction of the total content of analytes requires previous enzymatic hydrolysis of the bound forms. For preconcentration, chloroform (250 μl) and acetonitrile (1.5 ml) were added to 10 ml of the sample extract in the presence of 0.5 g sodium chloride. The absence of matrix effect in the samples allowed quantification against aqueous external standards. Limits of detection ranged between 5 and 30 ng/g, depending on the compound. Method accuracy was studied through recovery assays, with recoveries in the 82–115% range being obtained. Relative standard deviations for repeatability studies were lower than 12%. Four different samples of grapes were analyzed, being quantified linalool in its free form at concentrations in the 359–470 ng/g range, and benzyl alcohol, 2‐phenylethanol, and linalool oxide I and II in their bound forms between 52 and 464 ng/g.
Knowledge sharing in organization: Reviewing the foundations of the field and current themes using bibliometrics
Authors: Anand Amitabh , Dumazert Jean‐Pierre 
Published: June 2022

AbstractUnderstanding the history, evolution, and present tendencies of a discipline requires a thorough review of its literature. Despite various review studies on the field of knowledge management (KM), its subdiscipline ‘knowledge sharing’ has only seen a handful of investigations with a slew of limitations. As a result, the present work aims to conduct a review of existing literature on knowledge sharing (KS) using complementary bibliometric methodologies. To do this, we conduct our reviews using two complimentary bibliometric techniques: ‘Co‐citation Reference Analysis’ (CCA‐R) and ‘Bibliographic Coupling Document Analysis’ (BCA‐D), and we highlight the field's origins and current themes. We then map our findings using free science visualization software (VOS viewer). The study's implications are examined, and we show new paths for further research.
Dimensions of Network Polymers
Authors: Tobita Hidetaka 
Published: June 2022

AbstractThe mean‐square radius of gyration Rg2 and the graph diameter D of the network polymers formed through the random crosslinking of predetermined primary chains with a fixed number of intermolecular and intramolecular crosslinks are investigated by the numerical calculation based on the graph theory. In the case of ring‐free polymers, D is the longest end‐to‐end path length, sometimes referred to as the maximum span length. The expected Rg2‐value for a given D is found to follow a linear relationship, Rg2 = a D + b, similarly as in the cases of the ring‐free polymers. The proportional coefficient, a decreases approximately linearly with the number of intramolecular crosslinks kc, or the cycle rank in the graph theory, essentially independent of the total number k of crosslinks and the primary chain length distribution. The contraction factor g of the average Rg2 of the whole network polymer system is also governed by kc, and decreases with kc. One may be able to design and control the Rg2‐values of crosslinked polymers through the magnitude of D, which is usually easier to imagine than the complex 3D architecture.
Whole‐genome circulating tumor DNA methylation landscape reveals sensitive biomarkers of breast cancer
Authors: Hai Luo , Li Lingyu , Liu Zongzhi , Tong Zhongsheng , Sun Yingli 
Published: June 2022

AbstractThe changes in circulating tumor DNA (ctDNA) methylation are believed to be early events in breast cancer initiation, which makes them suitable as promising biomarkers for early diagnosis. However, applying ctDNA in breast cancer early diagnosis remains highly challenging due to the contamination of background DNA from blood and low DNA methylation signals. Here, we report an improved way to extract ctDNA, reduce background contamination, and build a whole‐genome bisulfite sequencing (WGBS) library from different stages of breast cancer. We first compared the DNA methylation data of 74 breast cancer patients with those of seven normal controls to screen candidate methylation CpG site biomarkers for breast cancer diagnosis. The obtained 26 candidate ctDNA methylation biomarkers produced high accuracy in breast cancer patients (area under the curve [AUC] = 0.889; sensitivity: 100%; specificity: 75%). Furthermore, we revealed potential ctDNA methylated CpG sites for detecting early‐stage breast cancer (AUC = 0.783; sensitivity: 93.44%; specificity: 50%). In addition, different subtypes of breast cancer could be well distinguished by the ctDNA methylome, which was obtained through our improved ctDNA‐WGBS method. Overall, we identified high specificity and sensitivity breast cancer‐specific methylation CpG site biomarkers, and they will be expected to have the potential to be translated to clinical practice.
Solid‐state 31P and 109Ag CP/MAS NMR as a powerful tool for studying of silver(I) complexes with N‐thiophosphorylated thiourea and thioamide ligands
Authors: Rakhmatullin Aydar , Brusko Vasiliy V. , Shcherbitskaya Elmira R. , Polovov Ilya B. , Bakirov Rinat , Bessada Catherine 
Published: June 2022

AbstractA family of three‐ and four‐coordinated silver(I) complexes of formulas [Ag(PPh3)2L], [Ag(PPh3)L], and [AgL]n with N‐thiophosphorylated thiourea and thioamide ligands of general formula RC(S)NHP(S)(OPri)2 [R = Ph, PhNH, iPrNH, tBuNH, NH2] have been studied by solid‐state 109Ag and 31P CPMAS NMR spectroscopy. 109Ag NMR spectra have provided valuable structural information about Ag coordination, which is in good accordance with the available crystal structure data. The data presented in this work represent a significant addition to the available 109Ag chemical shifts and chemical shifts anisotropies. The silver chemical shift ranges for different P,S‐environments and coordination state were discussed in detail. The 1J(31P–107/109Ag) and 2J(31P–31P) values were determined and analyzed.
Free‐breathing motion‐informed locally low‐rank quantitative 3D myocardial perfusion imaging
Authors: Hoh Tobias , Vishnevskiy Valery , Polacin Malgorzata , Manka Robert , Fuetterer Maximilian , Kozerke Sebastian 
Published: June 2022

PurposeTo propose respiratory motion‐informed locally low‐rank reconstruction (MI‐LLR) for robust free‐breathing single‐bolus quantitative 3D myocardial perfusion CMR imaging. Simulation and in‐vivo results are compared to locally low‐rank (LLR) and compressed sensing reconstructions (CS) for reference.MethodsData were acquired using a 3D Cartesian pseudo‐spiral in‐out k‐t undersampling scheme (R = 10) and reconstructed using MI‐LLR, which encompasses two stages. In the first stage, approximate displacement fields are derived from an initial LLR reconstruction to feed a motion‐compensated reference system to a second reconstruction stage, which reduces the rank of the inverse problem. For comparison, data were also reconstructed with LLR and frame‐by‐frame CS using wavelets as sparsifying transform (‐wavelet).Reconstruction accuracy relative to ground truth was assessed using synthetic data for realistic ranges of breathing motion, heart rates, and SNRs. In‐vivo experiments were conducted in healthy subjects at rest and during adenosine stress. Myocardial blood flow (MBF) maps were derived using a Fermi model.ResultsImproved uniformity of MBF maps with reduced local variations was achieved with MI‐LLR. For rest and stress, intra‐volunteer variation of absolute and relative MBF was lower in MI‐LLR (±0.17 mL/g/min [26%] and ±1.07 mL/g/min [33%]) versus LLR (±0.19 mL/g/min [28%] and ±1.22 mL/g/min [36%]) and versus ‐wavelet (±1.17 mL/g/min [113%] and ±6.87 mL/g/min [115%]). At rest, intra‐subject MBF variation was reduced significantly with MI‐LLR.ConclusionThe combination of pseudo‐spiral Cartesian undersampling and dual‐stage MI‐LLR reconstruction improves free‐breathing quantitative 3D myocardial perfusion CMR imaging under rest and stress condition.
Free‐breathing, non‐ECG, simultaneous myocardial T1, T2, T2*, and fat‐fraction mapping with motion‐resolved cardiovascular MR multitasking
Authors: Cao Tianle , Wang Nan , Kwan Alan C. , Lee Hsu‐Lei , Mao Xianglun , Xie Yibin , Nguyen Kim‐Lien , Colbert Caroline M. , Han Fei , Han Pei , Han Hui , Christodoulou Anthony G. , Li Debiao 
Published: June 2022

PurposeTo develop a free‐breathing, non‐electrocardiogram technique for simultaneous myocardial T1, T2, T2*, and fat‐fraction (FF) mapping in a single scan.MethodsThe MR Multitasking framework is adapted to quantify T1, T2, T2*, and FF simultaneously. A variable TR scheme is developed to preserve temporal resolution and imaging efficiency. The underlying high‐dimensional image is modeled as a low‐rank tensor, which allows accelerated acquisition and efficient reconstruction. The accuracy and/or repeatability of the technique were evaluated on static and motion phantoms, 12 healthy volunteers, and 3 patients by comparing to the reference techniques.ResultsIn static and motion phantoms, T1/T2/T2*/FF measurements showed substantial consistency (R > 0.98) and excellent agreement (intraclass correlation coefficient > 0.93) with reference measurements. In human subjects, the proposed technique yielded repeatable T1, T2, T2*, and FF measurements that agreed with those from references.ConclusionsThe proposed free‐breathing, non‐electrocardiogram, motion‐resolved Multitasking technique allows simultaneous quantification of myocardial T1, T2, T2*, and FF in a single 2.5‐min scan.
Delayed pregnancy detection and return to fertility with extended levonorgestrel‐containing oral contraceptives: A real world setting cohort study
Authors: Kaplan Sigal , Bertoia Monica L. , Lass Amir , Wang Florence T. , Evans Alison , Dhanda Sandeep , Roy Debabrata , Seeger John D. 
Published: June 2022

AbstractPurposeAs part of the European risk management plan of a 91‐day extended levonorgestrel‐containing combined oral contraceptive (COCLNG), a study was performed to assess its safety. This analysis was conducted to examine delayed pregnancy detection and return to fertility with extended combined oral contraceptives (COC).MethodsWe conducted a retrospective cohort study in new users of 91‐day COCLNG or 28‐day COCLNG within a US‐based healthcare claims database from 2006 to 2017. Delayed pregnancy detection during current COCLNG exposure was defined as the time between estimated pregnancy start and first prenatal care encounter. Additionally, the time between estimated pregnancy start and COCLNG discontinuation was measured. To measure return to fertility, pregnancy rates were estimated among females who discontinued treatment. 91‐day COCLNG users were propensity score‐matched to 28‐day COCLNG users. Hazard ratio for pregnancy was calculated using Cox proportional hazards models.ResultsThe 91‐day and 28‐day COCLNG users had 25 593 and 76 586 treatment episodes, respectively. The median time to pregnancy detection was 64.5 and 61.0 days (p = 0.24) in users of 91‐day COCLNG and 28‐day COCLNG. The median exposure time to treatment after estimated pregnancy start was 54.0 and 38.0 days (p < 0.01). In the fertility analysis, pregnancy rates were 54.82 (95% CI, 50.05–59.93) and 69.30 (95% CI, 64.98–73.82) per 1000 person‐years in extended COCLNG discontinuers and 28‐day COCLNG discontinuers. The adjusted hazard ratio of pregnancy was 0.77 (95% CI, 0.69–0.85).ConclusionsSmall differences were observed for pregnancy rates and delayed pregnancy detection between 91‐day extended COCLNG and 28‐day COCLNG, which may be related to the longer days' supply of extended COCLNG. Differences in the fertility analysis may be related to unmeasured residual confounding.
Recyclable photoluminescent composites via incorporating ZnS‐based phosphors into dynamic crosslinking elastomeric matrixes
Authors: Wang Jinyun , Xia Biao , Su Tong , Lin Tengfei , Gao Min , Zhao Chunlin , Wu Xiao , Lin Cong 
Published: June 2022

AbstractThe rapid advances in photochromic devices have spurred great enthusiasm in the design and preparation of luminescent materials. It is an efficient and facile strategy to incorporate ZnS‐based phosphors into crosslinking polymer substrates, obtaining photochromic materials with excellent comprehensive properties. However, crosslinking polymeric ZnS‐based phosphor luminous materials are unable to be recycled and reprocess at the end of service, limiting their long‐term utilization and burdening the environment. Besides, few reported works have explored photoluminescent properties of samples during multiple reprocessing and recycling. Herein, enlightened by the intriguing dynamic covalent crosslinking technology, recyclable and photoluminescent elastomers, employed polymeric flexible matrixes with dynamic covalent joints integrated with ZnS:Cu and ZnS:Cu,Mn phosphors, were prepared in this work. Due to the breakage and reformation of exchangeable crosslinking connections and intensive interfacial interactions between polar elastomeric matrixes and luminophores, the original and recycled composites exhibit excellent recyclable, photoluminescent, and mechanical properties. We anticipate that the strategy of this work, inserted phosphors into dynamic crosslinking polymer matrixes with a facile fabrication process, paves the way for the recycling and long‐term utilization of photoluminescent materials.
Optimal analytical strategies for sensitive and quantitative phosphoproteomics using TMT‐based multiplexing
Authors: Koenig Claire , Martinez‐Val Ana , Franciosa Giulia , Olsen Jesper V. 
Published: June 2022

AbstractIn large‐scale quantitative mass spectrometry (MS)‐based phosphoproteomics, isobaric labeling with tandem mass tags (TMTs) coupled with offline high‐pH reversed‐phase peptide chromatographic fractionation maximizes depth of coverage. To investigate to what extent limited sample amounts affect sensitivity and dynamic range of the analysis due to sample losses, we benchmarked TMT‐based fractionation strategies against single‐shot label‐free quantification with spectral library‐free data independent acquisition (LFQ‐DIA), for different peptide input per sample. To systematically examine how peptide input amounts influence TMT‐fractionation approaches in a phosphoproteomics workflow, we compared two different high‐pH reversed‐phase fractionation strategies, microflow (MF) and stage‐tip fractionation (STF), while scaling the peptide input amount down from 12.5 to 1 μg per sample. Our results indicate that, for input amounts higher than 5 μg per sample, TMT labeling, followed by microflow fractionation (MF) and phospho‐enrichment, achieves the deepest phosphoproteome coverage, even compared to single shot direct‐DIA analysis. Conversely, STF of enriched phosphopeptides (STF) is optimal for lower amounts, below 5 μg/peptide per sample. As a result, we provide a decision tree to help phosphoproteomics users to choose the best workflow as a function of sample amount.
Green and rapid fabrication of copper oxide in enhanced electrode liquid phase plasma system
Authors: Yang Jason H. C. , Wu Shang‐Lin , Tsai Cheng‐Shiun 
Published: June 2022

AbstractCopper(II) oxide nanoparticles have been successfully fabricated in a rapid fashion by a green method which requires nothing more than ultrapure water and copper pallets. In this study, liquid phase plasma system has been deployed to facilitate the synthesis process with tunable parameters of duty cycle (θ), pulse period (τ), copper pallet length, and the distance between electrodes, which essentially contributes to increased particle collision, extended reaction period, enlarged reactant size, and widened space, respectively. X‐ray diffraction (XRD) profile shows at 2 theta = 35.6° and 38.7°, along with Fourier‐transform infrared spectroscopy (FT‐IR) characteristic peaks at 435, 528, and 598 cm−1 confirm the presence of highly pure CuO nanoparticles with crystallites about 55–70 nm in length and 15–26 nm in width that develop agglomerated nanoparticles ranging 155–160 nm in size. Results also reveal that serrated structure electrodes can improve the particle formation rate by 32% from 0.22 to 0.29 g/h.
Defining and identifying early‐onset lung disease in cystic fibrosis with cumulative clinical characteristics
Authors: Huang Leslie , Lai HuiChuan J. , Antos Nicholas , Rock Michael J. , Asfour Fadi , Howenstine Michelle , Gaffin Jonathan M. , Farrell Philip M. 
Published: June 2022

AbstractBackgroundBecause of the heterogeneity in cystic fibrosis (CF) lung disease among young children, a clinical method to identify early‐onset lung disease is needed.ObjectiveTo develop a CF early‐onset lung disease (CFELD) scoring system by utilizing prospectively collected longitudinal data on manifestations in the first 3 years of life.DesignWe studied 145 infants born during 2012–2017, diagnosed through newborn screening by age 3 months, and followed to 36 months of age. Cough severity, pulmonary exacerbations (PEx), respiratory cultures, and hospitalizations were collected at each CF center visit (every 1–2 months in infancy and quarterly thereafter). These data were used to construct the CFELD system and to classify lung disease into five categories: asymptomatic, minimal, mild, moderate, and severe.ResultsThe most frequent manifestation of CF early lung disease was MD‐reported PEx episodes, PEx hospitalizations, and positive Pseudomonas aeruginosa cultures. Parent‐reported cough severity was correlated with the number of respiratory hospitalizations (r = 0.48, p < 0.0001). The distribution of CFELD categories was 10% asymptomatic, 17% minimal, 29% mild, 33% moderate, and 12% severe. The moderate and severe categories occurred threefold higher in pancreatic insufficient (PI, 49%) versus sufficient subjects (16%), p < 0.0001. In addition to PI, gastrointestinal and nutrition‐related hospitalizations, plasma cytokines interleukin (IL)‐6 and IL‐10, duration of CFTR modulator therapy, and type of health insurance were significant predictors of CFELD scores.ConclusionThe CFELD scoring system is novel, allows systematic evaluation of lung disease prognosis early, and may aid in therapeutic decision‐making particularly in the initiation of CFTR modulator therapy.
Understanding patterns of internal migration during the COVID‐19 pandemic in Spain
Authors: González‐Leonardo Miguel , López‐Gay Antonio , Newsham Niall , Recaño Joaquín , Rowe Francisco 
Published: June 2022

AbstractExisting empirical work has analysed the impacts of COVID‐19 on mortality, fertility and international migration. Less is known about the ways in which the COVID‐19 pandemic has influenced the patterns of internal migration. Anecdotal reports of mass migration from large cities to less populated areas have emerged, but lack of data has prevented empirically assessing this hypothesis. Drawing on geographically granular administrative population register data, we aim to analyse the extent of change in the patterns of internal migration across the urban hierarchy in Spain during 2020. Our results show a decline of 2.5% in the number of internal migration moves, particularly during the early stages of the pandemic, returning to pre‐pandemic levels in late 2020. Results also reveal unusually large net migration losses in core cities and net migration gains in rural areas. Net migration losses in cities and gains in rural areas particularly accumulated following the elimination of the strict lockdown measures in June. Yet, these net losses and gains trended to pre‐pandemic levels in late 2020, and movements between cities, and between cities and suburbs, continued to dominate the internal migration system. Thus, while the COVID‐19 pandemic exerted notable changes in the geographic balance of internal migration flows, these changes appear to have been temporary and did not significantly alter the existing structures of the national migration system.
Rainbow trees in uniformly edge‐colored graphs
Authors: Aigner‐Horev Elad , Hefetz Dan , Lahiri Abhiruk 
Published: June 2022

AbstractWe obtain sufficient conditions for the emergence of spanning and almost‐spanning bounded‐degree rainbow trees in various host graphs, having their edges colored independently and uniformly at random, using a predetermined palette. Our first result asserts that a uniform coloring of , using a palette of size , a.a.s. admits a rainbow copy of any given bounded‐degree tree on at most vertices, where is arbitrarily small yet fixed. This serves as a rainbow variant of a classical result by Alon et al. pertaining to the embedding of bounded‐degree almost‐spanning prescribed trees in , where is independent of . Given an ‐vertex graph with minimum degree at least , where is fixed, we use our aforementioned result in order to prove that a uniform coloring of the randomly perturbed graph , using colors, where is arbitrarily small yet fixed, a.a.s. admits a rainbow copy of any given bounded‐degree spanning tree. This can be viewed as a rainbow variant of a result by Krivelevich et al. who proved that , where is independent of , a.a.s. admits a copy of any given bounded‐degree spanning tree. Finally, and with as above, we prove that a uniform coloring of using colors a.a.s. admits a rainbow spanning tree. Put another way, the trivial lower bound on the size of the palette required for supporting a rainbow spanning tree is also sufficient, essentially as soon as the random perturbation a.a.s. has edges.