bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of high‐frequency interference characteristics of UHVDC converters
Authors: Ying Chaonan , Xu Zheng , Luo Chenxi 
Published: October 2018

The converter is the main component of the converter station and the main noise source of the PLC interference. The accurate modelling of the high‐frequency characteristics of the converter is the foundation for the design of the ± 1100 kV UHVDC PLC filter. Based on deep analysis of the high‐frequency characteristics of the converter valve, this paper first proposes three high‐frequency models of the converter valve. Compared with a real converter valve used in similar HVDC project, model two is chosen to analyse the high‐frequency characteristics. Second, the model of Zhundong–Wannan UHVDC transmission project is established in the PSCAD simulation platform to determine the actual high‐frequency characteristics of the converter valve. The voltage before the smoothing reactor is calculated, and the high‐frequency noise level is obtained by Fourier transform. Considering the practical application of the high‐frequency model of the converter valve, this paper finally proposes a formula to express the measured noise level. The noise source expressed by the formula is more practical for research on high‐frequency characteristics of the converter station.
Fire resistance test of transformers filled with natural ester insulating liquid
Authors: Cai Shengwei , Chen Cheng , Guo Huihao , Chen Shaobing , Zhou Zandong , Guo Zhaofeng 
Published: October 2018

Natural ester fluids, as a renewable, biodegradable liquid dielectric, its flash point is above 300°C, and the burning point exceeds 330°C, high flash point liquids known as ‘less flammable’ liquids. There is a possibility applying the natural ester fluid immersed transformer instead of dry type transformer in high fire resistance requirement occasion. In order to verify the fire resistance of natural ester insulating oil transformer, set forth a series of contrast test between natural ester insulating oil and mineral insulating oil, including flash point, burning point, explosion limits, metal hot surface test, and burning plate test. Through developing burning test platform of transformer to launch the burning test for 10 kV transformer of natural ester insulating oil. The results show that the transformer filled with natural ester fluid cannot burn for 30 min in the case of severe external fire, which provides a relatively abundant time for fire extinguishing and has certain fireproof performance. In addition, by improving the mechanical strength of transformer tank, install the specific pressure relief devices and using high temperature seal, bushing etc., which can improve the fire resistance of transformers filled with natural ester insulating fluids.
O2 signature in thin and thick O2−H2O ices
Authors: Müller B. , Giuliano B. M. , Bizzocchi L. , Vasyunin A. I. , Caselli P. 
Published: October 2018

Aims. In this paper we investigate the detectability of the molecular oxygen in icy dust grain mantles towards astronomical objects.
Methods. We present a systematic set of experiments with O2−H2O ice mixtures designed to disentangle how the molecular ratio affects the O2 signature in the mid- and near-infrared spectral regions. All the experiments were conducted in a closed-cycle helium cryostat coupled to a Fourier transform infrared spectrometer. The ice mixtures comprise varying thicknesses from 8 × 10−3 to 3 μm. The absorption spectra of the O2−H2O mixtures are also compared to the one of pure water. In addition, the possibility to detect the O2 in icy bodies and in the interstellar medium is discussed.
Results. We are able to see the O2 feature at 1551 cm−1 even for the most diluted mixture of H2O:O2 = 9:1, comparable to a ratio of O2/H2O = 10% which has already been detected in situ in the coma of the comet 67P/Churyumov-Gerasimenko. We provide an estimate for the detection of O2 with the future mission of the James Webb Space Telescope (JWST).
Sonographic Venous Velocity Index Identifies Patients with Chronic Kidney Disease and Severe Diastolic Dysfunction
Authors: Meier Markus , Jabs Wolfram Johannes , Guthmann Maria , Geppert Gesa , Aydin Ali , Nitschke Martin 
Published: October 2018

AbstractDiagnosing cardiorenal syndrome (CRS) in patients with chronic kidney disease (CKD) continues to remain challenging in outpatient practice. In this study, we investigate whether a newly developed venous velocity ultrasound index (VVI) can differentiate between patients with CRS and patients with CKD of other cause or normal renal function (NRF). Patients with CRS (n=30), CKD (n=30), and NRF (n=30) were included in the study. For each patient, duplex ultrasound scans of intrarenal segmental veins were retrospectively analyzed. The VVI was calculated from the renal venous doppler curve as the ratio of the maximal positive venous velocity to the maximal negative venous velocity. Patients with CRS were compared to age-matched controls with NRF and to GFR-matched controls with CKD. The GFRs of patients with CRS and those with CKD were comparable (26.4±5 and 25.6±7 ml/min/m2), as was the age in patients with CRS and NRF (6 ±12 years and 68±16 years, respectively). There was no significant difference in ejection fraction between patients with CRS and those with CKD (44.2±6.2% vs. 47.4 ±7.2), but there was a significant decrease compared to those with NRF (52.6 ±5.1, p<0.01). The VVI was significantly higher in the CRS group (0.81± 0.18) compared to the CKD group (0.18± 0.17, p<0.01) or NRF group (0.22± 0.20, p<0.01). The positive predictability of CRS was 96.4% in patients with VVI values of >0.6.
The newly developed VVI was useful in successfully predicting severe diastolic dysfunction (CRS) in patients with severe kidney injury in outpatient care.
Supratentorial and Infratentorial Approaches to Pineal Surgery: A Database Analysis
Authors: Rosenberg David M. , Geever Brett W. , Patel Akash S. , Chaker Anisse N. , Bhimani Abhiraj D. , Kheirkhah Pouyan , Hobbs Jonathan G. , Esfahani Darian R. , Mehta Ankit I. 
Published: October 2018

Objectives Neoplasms involving the pineal gland are rare. When they do occur, tumor resection is anatomically challenging and is traditionally addressed by either a supratentorial or an infratentorial approach. To date, no large, multicenter studies have been performed that systematically analyze outcomes comparing these two approaches. This study aimed to evaluate outcomes for patients undergoing pineal neoplasm resection, comparing supratentorial and infratentorial approaches.
Design Retrospective database review.
Setting Multi-institutional database.
Participants From 2005 to 2016, 60 patients were identified, with 13 undergoing a supratentorial approach and 47 undergoing an infratentorial approach.
Main Outcome Measures Patient demographics, comorbidities, and 30-day postoperative outcomes were investigated using the American College of Surgeons National Surgical Quality Improvement Program database. Demographics, readmission, reoperation, and complication rates were analyzed and compared with previous studies.
Results Patient demographics were similar between these two groups. The overall complication rates for the supratentorial and infratentorial approaches were 30.8 and 17%, respectively, and the difference was not statistically significant. The most common medical complications encountered were respiratory and hematological.
Conclusion As the first multi-institutional database analysis of approaches to the pineal gland, this study provides an analysis of patient demographics, comorbidities, and postoperative complications. After controlling for preoperative risk factors and demographic characteristics, no statistically significant differences in postoperative outcomes were found between infratentorial and supratentorial approaches. The mean readmission, reoperation, and complication rates were found to be 2.1, 8.3, and 20%, respectively. The lack of significant difference between approaches suggests that clinical decision-making should depend upon anatomical considerations and physician preference, although the complications illustrated here may provide some preoperative guidance.
Structured Training for Fetal Diagnostic Skills in a Maternal-Fetal Medicine Fellowship
Authors: Antony Kathleen , Khurshid Nauman , Trampe Barbara , Gupta Vivek , Iruretagoyena J. , Stewart Katharina , Shah Dinesh 
Published: October 2018

Objective The American Institute of Ultrasound in Medicine has described what constitutes a detailed fetal anatomic examination but what comprises an appropriate physician training program has not been described. The purpose of this paper is to describe a highly-structured program developed by our center to train maternal-fetal medicine fellows in a systematic approach to fetal diagnostic imaging.
Study Design We describe this approach in three phases. Phase I: Development of Skills as a Perinatal Sonographer, Phase II: Mentored Evolution to a Perinatal Sonologist and Phase III: Supervised Independent Practice as Consultant-in-training.
Results This curriculum was implemented in 2006. Of the eight maternal-fetal medicine fellows who completed this program, 100% were capable of following this curriculum and 100% felt comfortable performing and interpreting detailed sonograms including sonograms with significant and uncommon anomalies. Qualitative feedback was also positive. Finally, this structured approach resulted in an increase in the average total number of sonograms interpreted.
Conclusion Our curriculum, by following the explicit guidelines and expectations set out by the American Institute of Ultrasound in Medicine and the American Board of Obstetrics and Gynecology for practicing maternal-fetal medicine fellowship graduates, provides an opportunity to explore national standardization for this component of training.
Aspartoacylase: a central nervous system enzyme. Structure, catalytic activity and regulation mechanisms
Authors: Kots Ekaterina D. , Khrenova Maria G. , Nemukhin Alexander V. , Varfolomeev Sergei D. 
Published: October 2018

Aspartoacylase is a key enzyme in the human central nervous system. Catalytic deficiency of aspartoacylase is associated with several neurodegenerative disorders, which accounts for the enhanced interest in description of the catalytic action and regulatory mechanisms of this enzyme. This review focuses on molecular modelling of the catalytic function of aspartoacylase and the ways of its allosteric regulation in terms of modern theoretical chemistry approaches. The conclusions based on experimental data on the structure and functions of aspartoacylase accumulated during the last 20 years and conclusions drawn from computer modelling results of the last 5 years are analyzed in detail.
The bibliography includes 109 references.
Towards mechanisms and standardization in extracellular vesicle and extracellular RNA studies: results of a worldwide survey
Authors: Soekmadji Carolina , Hill Andrew F. , Wauben Marca H. , Buzás Edit I. , Di Vizio Dolores , Gardiner Chris , Lötvall Jan , Sahoo Susmita , Witwer Kenneth W. 
Published: October 2018

ABSTRACTThe discovery that extracellular vesicles (EVs) can transfer functional extracellular RNAs (exRNAs) between cells opened new avenues into the study of EVs in health and disease. Growing interest in EV RNAs and other forms of exRNA has given rise to research programmes including but not limited to the Extracellular RNA Communication Consortium (ERCC) of the US National Institutes of Health. In 2017, the International Society for Extracellular Vesicles (ISEV) administered a survey focusing on EVs and exRNA to canvass‐related views and perceived needs of the EV research community. Here, we report the results of this survey. Overall, respondents emphasized opportunities for technical developments, unraveling of molecular mechanisms and standardization of methodologies to increase understanding of the important roles of exRNAs in the broader context of EV science. In conclusion, although exRNA biology is a relatively recent emphasis in the EV field, it has driven considerable interest and resource commitment. The ISEV community looks forward to continuing developments in the science of exRNA and EVs, but without excluding other important molecular constituents of EVs.
A Daily Diary Study of Rumination and Health Behaviors: Modeling Moderators and Mediators
Authors: Riley Kristen E , Park Crystal L , Laurenceau Jean-Philippe 
Published: October 2018

Abstract

Objective
Rumination, thinking about a negative mood repetitively, is a common cognitive process that may affect health behavior engagement or avoidance. Little research has examined relations between rumination and health behaviors.

Purpose
We aimed to test links between rumination and health behaviors as well as possible moderators and mediators of those links.

Methods
We used an 11-day online daily diary design. Health behavior outcomes included fruit intake, vegetable intake, exercise, alcohol intake, sexual risk taking behavior, and cigarette smoking.

Results
Rumination was related to alcohol intake at the within-person level. Using multivariate modeling, we found that significant within-person mediators for rumination to health behaviors included impulsivity, amotivation, self control, and using health behaviors as coping, with each of these mediating relationships for one to four out of the five health behavior outcomes. A significant between-person moderator includes perceived behavioral control for alcohol intake only, and intention was not a significant moderator of the rumination to health behavior relationships.

Conclusions
Rumination affects various maladaptive health behaviors differentially, through a number of mechanisms and under a moderating condition whereby those who feel more control are better able to buffer rumination’s deleterious effects. Future interventions can apply the results to individual and multiple behavior change interventions for chronic disease prevention, especially for those who are particularly suffering from ruminative thoughts.
Association Between Maternal Iodine Intake in Pregnancy and Childhood Neurodevelopment at Age 18 Months
Authors: Zhou Shao J , Condo Dominique , Ryan Philip , Skeaff Sheila A , Howell Stuart , Anderson Peter J , McPhee Andrew J , Makrides Maria 
Published: October 2018

Abstract
There are limited and inconsistent data suggesting that mild iodine deficiency in pregnancy might be associated with poorer developmental outcomes in children. Between 2011 and 2015, we conducted a prospective cohort study in Australia examining the relationship between maternal iodine intake in pregnancy and childhood neurodevelopment, assessed using Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III), in 699 children at 18 months. Maternal iodine intake and urinary iodine concentration (UIC) were assessed at study entry (<20 weeks’ gestation) and at 28 weeks’ gestation. Maternal iodine intake in the lowest (<220 μg/day) or highest (≥391 μg/day) quartile was associated with lower cognitive, language, and motor scores (mean differences ranged from 2.4 (95% confidence interval (CI): 0.01, 4.8) to 7.0 (95% CI: 2.8, 11.1) points lower) and higher odds (odds ratios ranged from 2.7 (95% CI: 1.3, 5.6) to 2.8 (95% CI: 1.3, 5.7)) of cognitive developmental delay (Bayley-III score <1 standard deviation) compared with mothers with an iodine intake in the middle quartiles. There was no association between UIC in pregnancy and Bayley-III outcomes regardless of whether UIC and the outcomes were analyzed as continuous or categorical variables. Both low and high iodine intakes in pregnancy were associated with poorer childhood neurodevelopment in this iodine-sufficient population.
Intraoperative Indocyanine Green Angiography for Fat Necrosis Reduction in the Deep Inferior Epigastric Perforator (DIEP) Flap
Authors: Malagón-López Paloma , Vilà Jordi , Carrasco-López Cristian , García-Senosiain Oihane , Priego David , Julian Ibañez Juan F , Higueras-Suñe Carmen 
Published: October 2018

Abstract

Background
Fat necrosis is a frequent complication (up to 62.5%) of microsurgical breast reconstruction using the deep inferior epigastric perforator (DIEP) flap. This could have important clinical and psychological repercussions, deteriorating the results and increasing reconstruction costs.

Objectives
The aim of this study was to demonstrate the intraoperative use of indocyanine green angiography (ICGA) to reduce fat necrosis in DIEP flap.

Methods
Sixty-one patients who underwent unilateral DIEP flap procedures for breast reconstruction after oncological mastectomy were included (24 cases with intraoperative use of ICGA during surgery, 37 cases in the control group). The follow-up period was 1 year after surgery. The association between the use of ICGA and the incidence of fat necrosis in the first postoperative year, differences in fat necrosis grade (I-V), differences in fat necrosis requiring reoperation, quality of life, and patient satisfaction were analyzed.

Results
The incidence of fat necrosis was reduced from 59.5% (control group) to 29% (ICG-group) (P = 0.021) (relative risk = 0.49 [95% CI, 0.25-0.97]). The major difference was in grade II (27% vs 2.7%, P = 0.038). The number of second surgeries for fat necrosis treatment was also reduced (45.9% vs 20.8%, P = 0.046). The ICG group had higher scores on the BREAST-Q.

Conclusions
Intraoperative ICGA is a useful technique for reconstructive microsurgery that might improve patient satisfaction and reduce the incidence of fat necrosis by half as well as reduce its grade, especially in small fat necrosis cases; consequently, ICGA could reduce the number of secondary surgeries for treatment of fat necrosis.

Level of Evidence: 4
Measuring phylogenetic signal between categorical traits and phylogenies
Authors: Borges Rui , Machado João Paulo , Gomes Cidália , Rocha Ana Paula , Antunes Agostinho 
Published: October 2018

Abstract

Motivation
Determining whether a trait and phylogeny share some degree of phylogenetic signal is a flagship goal in evolutionary biology. Signatures of phylogenetic signal can assist the resolution of a broad range of evolutionary questions regarding the tempo and mode of phenotypic evolution. However, despite the considerable number of strategies to measure it, few and limited approaches exist for categorical traits. Here, we used the concept of Shannon entropy and propose the δ statistic for evaluating the degree of phylogenetic signal between a phylogeny and categorical traits.

Results
We validated δ as a measure of phylogenetic signal: the higher the δ-value the higher the degree of phylogenetic signal between a given tree and a trait. Based on simulated data we proposed a threshold-based classification test to pinpoint cases of phylogenetic signal. The assessment of the test’s specificity and sensitivity suggested that the δ approach should only be applied to 20 or more species. We have further tested the performance of δ in scenarios of branch length and topology uncertainty, unbiased and biased trait evolution and trait saturation. Our results showed that δ may be applied in a wide range of phylogenetic contexts. Finally, we investigated our method in 14 360 mammalian gene trees and found that olfactory receptor genes are significantly associated with the mammalian activity patterns, a result that is congruent with expectations and experiments from the literature. Our application shows that δ can successfully detect molecular signatures of phenotypic evolution. We conclude that δ represents a useful measure of phylogenetic signal since many phenotypes can only be measured in categories.

Availability and implementation
https://github.com/mrborges23/delta_statistic.

Supplementary information
Supplementary data are available at Bioinformatics online.
A framework for identifying dysregulated chromatin regulators as master regulators in human cancer
Authors: Ru Beibei , Sun Jianlong , Kang Qingzheng , Tong Yin , Zhang Jiangwen 
Published: October 2018

Abstract

Motivation
Chromatin regulators (CRs) are frequently dysregulated to reprogram the epigenetic landscape of the cancer genome. However, the underpinnings of the dysregulation of CRs and their downstream effectors remain to be elucidated.

Results
Here, we designed an integrated framework based on multi-omics data to identify candidate master regulatory CRs affected by genomic alterations across eight cancer types in The Cancer Genome Atlas. Most of them showed consistent activated or repressed (i.e. oncogenic or tumor-suppressive) roles in cancer initiation and progression. In order to further explore the insight mechanism of the dysregulated CRs, we developed an R package ModReg based on differential connectivity to identify CRs as modulators of transcription factors (TFs) involved in tumorigenesis. Our analysis revealed that the connectivity between TFs and their target genes (TGs) tended to be disrupted in the patients who had a high expression of oncogenic CRs or low-expression of tumor-suppressive CRs. As a proof-of-principle study, 14 (82.4%) of the top-ranked 17 driver CRs in liver cancer were able to be validated by literature mining or experiments including shRNA knockdown and dCas9-based epigenetic editing. Moreover, we confirmed that CR SIRT7 physically interacted with TF NFE2L2, and positively modulated the transcriptional program of NFE2L2 by affecting ∼64% of its TGs.

Availability and implementation
ModReg is freely accessible at http://cis.hku.hk/software/ModReg.tar.gz.

Supplementary information
Supplementary data are available at Bioinformatics online.
18β-glycyrrhetinic acid inhibited mitochondrial energy metabolism and gastric carcinogenesis through methylation-regulated TLR2 signaling pathway
Authors: Cao Donghui , Wu Yanhua , Jia Zhifang , Zhao Dan , Zhang Yangyu , Zhou Tianyu , Wu Menghui , Zhang Houjun , Tsukamoto Tetsuya , Oshima Masanobu , Jiang Jing , Cao Xueyuan 
Published: October 2018

Abstract
The natural phenolic substance, 18β-glycyrrhetinic acid (GRA), has shown enormous potential in the chemoprevention of cancers with rich resources and biological safety, but the GRA-regulated genetic and epigenetic profiles are unclear. Deregulated mitochondrial cellular energetics supporting higher adenosine triphosphate provisions relative to the uncontrolled proliferation of cancer cells is a cancer hallmark. The Toll-like receptor 2 (TLR2) signaling pathway has emerged as a key molecular component in gastric cancer (GC) cell proliferation and epithelial homeostasis. However, whether TLR2 influenced GC cell energy metabolism and whether the inhibition effects of GRA on GC relied on TLR2 signaling were not illustrated. In the present study, TLR2 mRNA and protein expression levels were elevated in gastric tumors in the K19-Wnt1/C2mE (Gan) mice model, GC cell lines and human GCs, and the overexpression of TLR2 was correlated with the high histological grade and was a poor prognostic factor in GC patients. Further gain and loss of function showed that TLR2 activation induced GC cell proliferation and promoted reactive oxygen species (ROS) generation, Ca2+ accumulation, oxidative phosphorylation and the electron transport chain, while blocking TLR2 inhibited mitochondrial function and energy metabolism. Furthermore, GRA pretreatment inhibited TLR2-activated GC cell proliferation, energy metabolism and carcinogenesis. In addition, expression of TLR2 was found to be downregulated by GRA through methylation regulation. Collectively, the results demonstrated that GRA inhibited gastric tumorigenesis through TLR2-accelerated energy metabolism, suggesting GRA as a promising therapeutic agency targeting TLR2 signaling in GC.