bluuebunny/crossref_metadata_2025_split huggingface dataset:
The wind‐driven formation of cross‐shelf sediment plumes in a large lake
Authors: McKinney Paul , Austin Jay , Fai Gills 
Published: February 2019

AbstractWind‐driven turbidity plumes frequently occur in the western arm of Lake Superior and may represent a significant cross‐shelf transport mechanism for sediment, nutrient, and biota. Here, we characterize a plume that formed in late April 2016 using observations from in situ sensors and remote sensing imagery, and estimate the volume of cross‐shelf transport using both the observations and an idealized analytical model of plume formation. The steady‐state, barotropic model is used to determine a relationship between the intensity and duration of a wind event and the volume of water transported from nearshore to offshore during the event. The model transport is the result of nearshore flow in the direction of the wind and a pressure‐gradient‐driven counter flow in the deeper offshore waters, consistent with observations. The volume of offshore transport associated with the 2016 plume is estimated by both methods to have been on the order of 1010 m3. Analysis of similar events from 2008 to 2016 shows a strong relationship between specific wind impulse and plume volume. Differences in the intensity and duration of individual events as well as ice cover, which prevents plume formation, lead to interannual variability of offshore transport ranging over an order of magnitude and illustrates how wind‐driven processes may contribute to interannual variability of ecosystem functioning.
Effort reduction of employer‐to‐employer changers: Empirical evidence from football
Authors: Weimar Daniel , Scharfenkamp Katrin 
Published: February 2019

We investigate changes in effort investment of employees who still fulfill a contract with their current employer but already signed a follow‐up contract with a new employer (employer‐to‐employer change). Because effort and outside contract assignments are hard to measure in firms, we use running data from professional football (n = 26,577) to proxy effort decisions. Fixed effect regressions reveal a statistically significant but weak reduction in a player's effort after signing a follow‐up contract with a new club. Because we find a statistically significant effort reduction in public sports, this effect might be even larger in less transparent labor markets.
Upregulation of miR‐200a and miR‐204 in MPP+‐treated differentiated PC12 cells as a model of Parkinson’s disease
Authors: Talepoor Ardakani Maryam , Rostamian Delavar Mahsa , Baghi Masoud , Nasr‐Esfahani Mohammad Hossein , Kiani‐Esfahani Abbas , Ghaedi Kamran 
Published: February 2019

AbstractBackgroundParkinson's disease (PD) is ranked as the second most common neurodegenerative disorder caused by loss of dopaminergic neurons in the substantia nigra. Micro(mi)RNAs are a class of small noncoding RNAs that regulate gene expression and aberrant expression of them is closely correlated with many neurodegenerative conditions including PD. Silent information regulator 1 (SIRT1) as a known deacetylase and B‐cell lymphoma‐2 (BCL2) as an antiapoptotic factor play vital roles in neural protection and survival.MethodsDifferentiated PC12 cells exposed to MPP+ were served here as a known PD model. Cell viability was determined by MTS assay. Apoptotic cells and ROS levels were detected using flow cytometry. Gene selection and miRNA–mRNA interaction analysis were performed through in silico methods. Relative expression of miRNAs and genes was examined by RT‐qPCR.ResultsMPP+ exposure markedly reduced cell viability, enhanced oxidative stress, and induced apoptosis in differentiated PC12 cells. Sirt1 and BCL2were shown to be markedly declined in response to MPP+, while miR‐200a and miR‐204 were significantly upregulated.ConclusionThe first novel finding of the current study is altered expression of miR‐200a and miR‐204 in differentiated PC12 cells in response to MPP+, suggesting that deregulation of them participate in MPP+ neurotoxicity mechanisms, possibly via affecting the expression of Sirt1 and BCL2 as potential targets.
Association between polymorphisms in CXCR2 gene and preeclampsia
Authors: Chen Hongqin , Zhang Yanping , Dai Li , Song Yaping , Wang Yanyun , Zhou Bin , Zhou Rong 
Published: February 2019

AbstractBackgroundPreeclampsia is a serious pregnancy‐specific syndrome with incompletely understood pathogenesis. Previous study has demonstrated that the decreased CXCR2 in preeclamptic placentas may contribute to the development of preeclampsia. The role of single nucleotide polymorphisms (SNPs) of CXCR2 gene in the pathogenesis of preeclampsia remains largely unexplored. Thus, we aimed to investigate the association between polymorphisms of CXCR2 gene and preeclampsia in Han Chinese women.MethodsTotally 481 pregnant women, including 243 controls and 238 patients with preeclampsia were recruited. The rs1126579 and rs2230054 polymorphisms in CXCR2 gene were tested using polymerase chain reaction‐restriction fragment length polymorphism method.ResultsSignificantly increased risk of preeclampsia was observed in the rs1126579 CC or TC/CC genotypes when compared with TT genotype (CC vs. TT: odss ratio [OR] = 2.11, 95% confidence interval [CI] = 1.18–3.76, p = 0.039; TC/CC vs. TT: OR = 1.89, 95% CI = 1.29–2.78, p = 0.001). Markedly higher risk of preeclampsia was found to be associated with rs1126579 TC genotype (TC vs. TT/CC: OR = 1.48, 95% CI = 1.04–2.12, p = 0.031). After stratification analysis, the different distribution of TC/CC genotypes was particularly significant in the severe preeclampsia group (OR = 2.15, 95% CI = 1.42–3.24, p < 0.01), the early‐onset severe preeclampsia group (OR = 1.97, 95% CI = 1.14–3.42, p = 0.013), and the late‐onset severe preeclampsia group (OR = 2.29, 95% CI = 1.39–3.78, p < 0.01). Besides, TC genotype carriers had a 1.55 fold increased risk of severe preeclampsia (95% CI = 1.06–2.27, p = 0.022) and a 1.80 fold increased risk of late onset severe preeclampsia (95% CI = 1.14–2.83, p = 0.01) than those of TT/CC genotype carriers.ConclusionsOur study suggests a genetic association between rs1126579 polymorphism in CXCR2 gene and increased risk of preeclampsia. These data provide a new clue for future investigation.
A fully reconfigurable bandpass‐to‐notch filter with wide bandwidth tuning range based on external quality factor tuning and multiple‐mode resonator
Authors: Lan BoZhang , Qu Yan , Guo ChenJiang , Ding Jun 
Published: February 2019

AbstractA fully reconfigurable microstrip bandpass‐to‐notch filter based on varactors is presented in this article. This filter offers wide center frequency and bandwidth tuning flexibility under bandpass mode and wide notch tuning range under notch mode. The entire tuning ability is based on multiple‐mode resonator (MMR) theory and tunable external quality factor for bandpass mode and the introduction of transmission zero (TZ) for notch mode. Under the bandpass mode, the center frequency tuning range is 0.9 to 1.42 GHz, and the bandwidth can be tuned from 0.09 to 1.44 GHz at a fixed center frequency 1.28 GHz. Under notch mode, the notch can be tuned from 0.98 to 2.02GHz. Good agreement can be observed between simulated and measured results.
Automated selection of myocardial inversion time with a convolutional neural network: Spatial temporal ensemble myocardium inversion network (STEMI‐NET)
Authors: Bahrami Naeim , Retson Tara , Blansit Kevin , Wang Kang , Hsiao Albert 
Published: February 2019

PurposeDelayed enhancement imaging is an essential component of cardiac MRI, which is used widely for the evaluation of myocardial scar and viability. The selection of an optimal inversion time (TI) or null point (TINP) to suppress the background myocardial signal is required. The purpose of this study was to assess the feasibility of automated selection of TINP using a convolutional neural network (CNN). We hypothesized that a CNN may use spatial and temporal imaging characteristics from an inversion‐recovery scout to select TINP, without the aid of a human observer.MethodsWe retrospectively collected 425 clinically acquired cardiac MRI exams performed at 1.5 T that included inversion‐recovery scout acquisitions. We developed a VGG19 classifier ensembled with long short‐term memory to identify the TINP. We compared the performance of the ensemble CNN in predicting TINP against ground truth, using linear regression analysis. Ground truth was defined as the expert physician annotation of the optimal TI. In a backtrack approach, saliency maps were generated to interpret the classification outcome and to increase the model’s transparency.ResultsPrediction of TINP from our ensemble VGG19 long short‐term memory closely matched with expert annotation (ρ = 0.88). Ninety‐four percent of the predicted TINP were within ±36 ms, and 83% were at or after expert TI selection.ConclusionIn this study, we show that a CNN is capable of automated prediction of myocardial TI from an inversion‐recovery experiment. Merging the spatial and temporal characteristics of the VGG‐19 and long short‐term‐memory CNN structures appears to be sufficient to predict myocardial TI from TI scout.
Load‐bearing biodegradable polycaprolactone‐poly (lactic‐co‐glycolic acid)‐ beta tri‐calcium phosphate scaffolds for bone tissue regeneration
Authors: Kumar Alok , Zhang Yiren , Terracciano Amalia , Zhao Xiao , Su Tsan‐Liang , Kalyon Dilhan M. , Katebifar Sara , Kumbar Sangamesh G. , Yu Xiaojun 
Published: February 2019

A biodegradable scaffold with tissue ingrowth and load‐bearing capabilities is required to accelerate the healing of bone defects. However, it is difficult to maintain the mechanical properties as well as biodegradability and porosity (necessary for bone ingrowth) at the same time. Therefore, in the present study, polycaprolactone (PCL) and poly (lactic‐co‐glycolic acid) (PLGA5050) were mixed in varying ratio and incorporated with 20 wt.% beta tri‐calcium phosphate (βTCP). The mixture was shaped under pressure into originally nonporous cylindrical constructs. It is envisioned that the fabricated constructs will develop porosity with the time‐dependent biodegradation of the polymer blend. The mechanical properties will be sustained since the decrease in mechanical properties associated with the dissolution of the PLGA, and the formation of the porous structure will be compensated with the new bone formation and ingrowth. To prove the hypothesis, we have systematically studied the effects of samples composition on the time‐dependent dissolution behavior, pore formation, and mechanical properties of the engineered samples, in vitro. The highest initial (of as‐prepared samples) values of the yield strength (0.021 ± 0.002 GPa) and the Young's modulus (0.829 ± 0.096 GPa) were exhibited by the samples containing 75 wt.% of PLGA. Increase of the PLGA concentration from 25 to 75 wt.% increased the rate of biodegradation by a factor of 3 upon 2 weeks in phosphate buffered saline (1 × PBS). The overall porosity and the pore sizes increased with the dissolution time indicating that the formation of in situ pores can indeed enable the migration of cells followed by vascularization and bone growth.
Enhancement of mechanical and barrier properties of LLDPE composite film via PET fiber incorporation for agricultural application
Authors: R. Pon Kumar , Wadgaonkar Kunal , Mehta Linchon , Jagtap Ramanand 
Published: February 2019

A study was conducted to determine the potential of linear low‐density polyethylene (LLDPE)‐PET fiber composite films to be used as an agricultural mulching film. Incorporation of 1 wt% PET fiber into the LLDPE matrix improved the tensile strength and percent elongation. The water vapor transmission rate was significantly lowered because of the presence of PET fibers. Also, the effect of continuous exposure of films to pesticide and UV light has been reported in terms of deterioration of mechanical and optical properties of the films. Differential scanning calorimetry shows that there is no effect of the presence of PET fibers on processing temperature of LLDPE at optimized loading; however, it was found that it lowers the latent heat of fusion and crystallization.
Local hyperthyroidism promotes pancreatic acinar cell proliferation during acute pancreatitis
Authors: Malagola Ermanno , Chen Rong , Bombardo Marta , Saponara Enrica , Dentice Monica , Salvatore Domenico , Reding Theresia , Myers Stephen , Hills Andrew P , Graf Rolf , Sonda Sabrina 
Published: February 2019

AbstractProliferation of pancreatic acinar cells is a critical process in the pathophysiology of pancreatic diseases, because limited or defective proliferation is associated with organ dysfunction and patient morbidity. In this context, elucidating the signalling pathways that trigger and sustain acinar proliferation is pivotal to develop therapeutic interventions promoting the regenerative process of the organ. In this study we used genetic and pharmacological approaches to manipulate both local and systemic levels of thyroid hormones to elucidate their role in acinar proliferation following caerulein‐mediated acute pancreatitis in mice. In addition, molecular mechanisms mediating the effects of thyroid hormones were identified by genetic and pharmacological inactivation of selected signalling pathways.In this study we demonstrated that levels of the thyroid hormone 3,3′,5‐triiodo‐l‐thyronine (T3) transiently increased in the pancreas during acute pancreatitis. Moreover, by using genetic and pharmacological approaches to manipulate both local and systemic levels of thyroid hormones, we showed that T3 was required to promote proliferation of pancreatic acinar cells, without affecting the extent of tissue damage or inflammatory infiltration.Finally, upon genetic and pharmacological inactivation of selected signalling pathways, we demonstrated that T3 exerted its mitogenic effect on acinar cells via a tightly controlled action on different molecular effectors, including histone deacetylase, AKT, and TGFβ signalling.In conclusion, our data suggest that local availability of T3 in the pancreas is required to promote acinar cell proliferation and provide the rationale to exploit thyroid hormone signalling to enhance pancreatic regeneration. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Plasma Epstein–Barr virus DNA as an archetypal circulating tumour DNA marker
Authors: Lam Wai Kei Jacky , Chan Kwan Chee Allen , Lo Yuk Ming Dennis 
Published: February 2019

AbstractAnalysis of circulating tumour DNA (ctDNA), as one type of ‘liquid biopsy’, has recently attracted great attention. Researchers are exploring many potential applications of liquid biopsy in many different types of cancer. In particular, it is of biological interest and clinical relevance to study the molecular characteristics of ctDNA. For such purposes, plasma Epstein–Barr virus (EBV) DNA from patients with nasopharyngeal carcinoma (NPC) would provide a good model to understand the biological properties and clinical applications of ctDNA in general. The strong association between EBV and NPC in endemic regions has made plasma EBV DNA a robust biomarker for this cancer. There are many clinical utilities of plasma EBV DNA analysis in NPC diagnostics. Its role in prognostication and surveillance of recurrence is well established. Plasma EBV DNA has also been validated for screening NPC in a recent large‐scale prospective study. Indeed, plasma EBV DNA could be regarded as an archetypal ctDNA marker. In this review, we discuss the biological properties of plasma EBV DNA from NPC samples and also the clinical applications of plasma EBV DNA analysis in the management of NPC. Of note, the recently reported size analysis of plasma EBV DNA in patients with NPC has highlighted size as an important analytical parameter of ctDNA and demonstrated clinical value in improving the diagnostic performance of an EBV DNA‐based NPC screening test. Such insights into ctDNA analysis (including size profiling) may help its full potential in cancer diagnostics for other types of cancer to be realised. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Fetal MRI findings in a retrospective cohort of 26 cases of prenatally diagnosed CHARGE syndrome individuals
Authors: Millischer Anne‐Elodie , Sonigo Pascale , Attie Tania , Spaggiari Emmanuel , O'Gorman Neil , Bessieres Bettina , Kermorvant Elsa , Boddaert Nathalie , Salomon Laurent‐Julien , Grevent David 
Published: February 2019

Abstract“CHARGE syndrome” (CS) is a multifaceted syndrome associated with a poor prognosis. The prenatal diagnosis remains challenging especially as the fetal anomalies that may evoke suspicion of CS are not comprehensively described.ObjectiveThis study aims to identify the anomalies in MRI with suspected CHARGE syndrome and to propose a possible standardization in the image‐based prenatal diagnosis of CS.MethodsThis was a retrospective study of 26 fetuses who underwent MRI and had a confirmed diagnosis of CS, as proven by histopathological and/or neonatal examinations and/or the presence of the CHD7 gene mutation.ResultsThe three most frequent MRI anomalies confirmed at histopathological and/or neonatal examinations were arhinencephaly in 100% (26 of 26), dysplasia of the semicircular canals agenesis (SCA) in 100% (24 of 24), and posterior fossa anomalies in 100% (22 of 22). Our study also revealed short petrous bones with a particular triangular shape in 24 of 24 cases of SCA. Other relevant findings included external ear anomalies in 36% (9 of 25), cleft lip and palate (9 of 9), ventriculomegaly (VMG) (6 of 6), short corpus callosum (3 of 3), and ocular asymmetry in 36.6% (4 of 11).ConclusionOur study emphasizes the interest of fetal MRI in the diagnosis of CS with an adapted knowledge of semiology.
Miktoarm star‐shaped poly(lactic acid) copolymer: Synthesis and stereocomplex crystallization behavior
Authors: Xie Pengfei , Wang Jiao , Li Jianbo , Cheng Qian , Zhou Keyu , Ren Jie 
Published: February 2019

ABSTRACTThe miktoarm star‐shaped poly(lactic acid) (PLA) copolymer, (PLLA)2‐core‐(PDLA)2, was synthesized via stepwise ring‐opening polymerization of lactide with dibromoneopentyl glycol as the starting material. 1H NMR and FTIR spectroscopy proved the feasibility of synthetic route and the successful preparation of star‐shaped PLA copolymers. The results of FTIR spectroscopy and XRD showed that the stereocomplex structure of the copolymer could be more perfect after solvent dissolution treatment. Effect of chain architectures on crystallization was investigated by studying the nonisothermal and isothermal crystallization of the miktoarm star‐shaped PLA copolymer and other stereocomplexes. Nonisothermal differential scanning calorimetry and polarizing optical microscopy tests indicated that (PLLA)2‐core‐(PDLA)2 exhibited the fastest formation of a stereocomplex in a dynamic test due to its special structure. In isothermal crystallization tests, the copolymer exhibited the fast crystal growth rate and the most perfect crystal morphology. The results reveal that the unique molecular structure has an important influence on the crystallization of the miktoarm star‐shaped PLA copolymer. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 814–826
Dissociation mechanism of GDP from Cdc42 via DOCK9 revealed by molecular dynamics simulations
Authors: Kang Ning , Liu Jiansheng , Zhao Yaxue 
Published: February 2019

AbstractCell division control protein 42 homolog (Cdc42) influences a variety of cellular responses such as cell migration and polarity. Deregulation of Cdc42 has been associated with several human diseases and developmental disorders. Over‐activation of Cdc42 through guanine nucleotide exchange factor (GEF) is a critical event for Cdc42 involved cancer metastasis. Members of DOCK family of GEF are important activators of Cdc42. However, this activation mechanism is still unknown. Molecular dynamics (MD) simulations and molecular mechanics‐Poisson‐Boltzmann surface area (MM‐PBSA) calculations were employed to investigate the central step of the activation of Cdc42: the dissociation mechanism of GDP from Cdc42 via DOCK9. Simulation results show that Mg2+ ion has a remarkable influence on the conformational change of switch I of Cdc42 through residue Pro34 which functions as a “clasp” to control the flexibility of switch I. In the GDP dissociation process, the Mg2+ ion leave first to result in a suitable conformation of Cdc42 for following DOCK9 binding to. When DOCK9 binds to Cdc42, it changes the orientations of residues Lys16, Thr17, Cys18 and Phe28 of Cdc42 to weaken the interactions between Cdc42 and GDP to release GDP. This study first elucidates the dissociation mechanism of GDP from Cdc42 via DOCK9 and identifies the essential residues of Cdc42 in this process. These simulation results are consistent with the recent findings of biochemical and amino acid mutational studies, and the observations are beneficial to understand the activation mechanism of Cdc42 and to provide insights for designing compounds targeting on Cdc42 related cancer metastasis.
Conformational sampling and polarization of Asp26 in pKa calculations of thioredoxin
Authors: Gomez Aharon , Vöhringer‐Martinez Esteban 
Published: February 2019

AbstractThioredoxin is a protein that has been used as model system by various computational methods to predict the pKa of aspartate residue Asp26 which is 3.5 units higher than a solvent exposed one (eg, Asp20). Here, we use extensive atomistic molecular dynamics simulations of two different protonation states of Asp26 in combination with conformational analysis based on RMSD clustering and principle component analysis to identify representative conformations of the protein in solution. For each conformation, the Gibbs free energy of proton transfer between Asp26 and Asp20, which is fully solvated in a loop region of the protein, is calculated with the Amber99sb force field in alchemical transformations. The varying polarization of the two residues in different molecular environments and protonation states is described by Hirshfeld‐I (HI) atomic charges obtained from the averaged polarized electron density. Our results show that the Gibbs free energy of proton transfer is dependent on the protein conformation, the proper sampling of the neighboring Lys57 residue orientations and on water molecules entering the hydrophobic cavity upon deprotonating Asp26. The inclusion of the polarization of both aspartate residues in the free energy cycle by HI atomic charges corrects the results from the non‐polarizable force field and reproduces the experimental ΔpKa value of Asp26.