bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust segmentation of optic disc and optic cup using statistical Kurtosis test
Authors: Biswal Birendra , Eadara Vyshnavi , Bebarta Dwiti K. , Sahu Gupteswar 
Published: December 2019

AbstractGlaucoma is a chronic and irreversible eye disease that leads to the loss of vision. Evaluation of the Cup to Disc Ratio (CDR) plays a prominent role in the early detection of glaucoma. This paper presents a novel algorithm to compute the CDR for the fundus images. In order to calculate the CDR, the vertical diameter of Optic Disc (OD) and the vertical diameter of the Optic Cup (OC) are calculated from the segmented OD and segmented OC, respectively. This study presents OD and OC segmentation algorithms based on a new statistics‐based kurtosis test. A unique OC boundary segmentation method is presented, which is the combination of partial cup extraction and the cup boundary under the Central Retinal Blood vessels (CRBV). A novel preprocessing technique is introduced to extract the CRBV from the automated Region of Interest (ROI). The experimental results confirm that the proposed algorithm outperforms the state‐of‐art OD and OC segmentation on the three publicly available datasets: ORIGA, DIARETDB0, and DIARETDB1. The proposed OD and OC segmentation achieve accuracies of up to 0.99 and 0.97, respectively. In addition, the proposed model achieves excellent CDR evaluation with an average error percentage reduced to up to 9.6496 for the considered datasets.
Factors that affect the translation of dietary restriction into a longer life
Authors: von Frieling Jakob , Roeder Thomas 
Published: December 2019

AbstractNutritional interventions, such as dietary or calorie restriction, are known to have a variety of health‐promoting effects. The most impressive are the direct effects on life expectancy, which have been reproduced in many animal models. A variety of dietary restriction protocols have been described, which differ either in their macronutrient composition or in the time window for consumption. Mechanistically, the effects of dietary restriction are mediated mainly through signaling pathways that have central roles in the maintenance of cellular energy balance. Among these, target of rapamycin and insulin signaling appear to be the most important. Such nutritional interventions can have their effects in two different ways: either by direct interaction with the metabolism of the host organism, or by modulating the composition and performance of its endogenous microbiome. Various dietary restriction regimens have been identified that significantly alter the microbiome and thus profoundly modulate host metabolism. This review aims to discuss the mechanisms by which dietary restriction can affect life expectancy, and in particular the role of the microbiome.
Sublethal exposure to propylparaben leads to lipid metabolism impairment in zebrafish early‐life stages
Authors: Perugini Monia , Merola Carmine , Amorena Michele , D'Angelo Michele , Cimini Annamaria , Benedetti Elisabetta 
Published: December 2019

AbstractParabens are widely used in cosmetics, toiletries, food and pharmaceuticals. Toxicological effects of parabens on human lipid metabolism are not well established. The present study used the early‐life stages of zebrafish (Danio rerio) to determine the toxicity of propylparaben (PP). The embryos were exposed for 96 hours postfertilization (hpf) at five different concentrations of PP, and lethal and sublethal alterations were recorded daily. The lethal concentration 50 (LC50) value was 3.98 mg/L. The most common sublethal alterations recorded at 1 and 2 mg/L were an enlarged and misshaped yolk sac, hyperexcitability, and reduction in head size and swim bladder. At sublethal concentrations of 1 and 2 mg/L, we observed an altered lipid metabolism, in terms of decrease in neutral lipid mobilization from yolk and alteration of phospholipid metabolism, both in the body and in the yolk sac. These observations were combined with strong head cartilage defects, indicating a strong effect of PP on head development. This research demonstrates that PP interferes with lipid utilization in zebrafish during early‐life stages that might be involved in neurological and skeletal abnormalities.
Effect of the Solute Cavity on the Solvation Energy and its Derivatives within the Framework of the Gaussian Charge Scheme
Authors: Garcia‐Ratés Miquel , Neese Frank 
Published: December 2019

AbstractThe treatment of the solvation charges using Gaussian functions in the polarizable continuum model results in a smooth potential energy surface. These charges are placed on top of the surface of the solute cavity. In this article, we study the effect of the solute cavity (van der Waals‐type or solvent‐excluded surface‐type) using the Gaussian charge scheme within the framework of the conductor‐like polarizable continuum model on (a) the accuracy and computational cost of the self‐consistent field (SCF) energy and its gradient and on (b) the calculation of free energies of solvation. For that purpose, we have considered a large set of systems ranging from few atoms to more than 200 atoms in different solvents. Our results at the DFT level using the B3LYP functional and the def2‐TZVP basis set show that the choice of the solute cavity does neither affect the accuracy nor the cost of calculations for small systems (< 100 atoms). For larger systems, the use of a vdW‐type cavity is recommended, as it prevents small oscillations in the gradient (present when using a SES‐type cavity), which affect the convergence of the SCF energy gradient. Regarding the free energies of solvation, we consider a solvent‐dependent probe sphere to construct the solvent‐accessible surface area required to calculate the nonelectrostatic contribution to the free energy of solvation. For this part, our results for a large set of organic molecules in different solvents agree with available experimental data with an accuracy lower than 1 kcal/mol for both polar and nonpolar solvents.
Nickel‐mediated cross‐coupling via C–O activation assisted by organoaluminum
Authors: Liu Cheng‐Yuan , Wititsuwannakul Taveechai , Hsieh Chu‐Han , Tsai Chung‐Yu , Wang Ting‐Hsuan , Ambre Ram , Chen Wen‐Ching , Surawatanawong Panida , Ong Tiow‐Gan 
Published: December 2019

AbstractWe report the alkylation and arylation cross‐coupling of aryl ethers based on C–O bond activation using a nickel catalyst and organoaluminum reagents. Ni(cod)2 in combination with 1,2‐bis(dicyclohexylphosphino)ethane ligand in toluene solution at 130°C are the best conditions. The naphthyl ether or methoxy pyridine derivatives are suitable substrates for alkylation and arylation reaction with a wider scope of aluminum reagents in good yields. Computational analysis on the pyridine substrate is provided to help delineate the mechanistic pathway and demonstrate the important aspects of the cooperative interaction bimetallic catalysis. First, the coordination of AlMe3 to the O atom of pyridine is essential for C–O activation. Second, the β‐H transfer from methoxy to pyridine could be discouraged through the use of bidentate phosphine as a ligand. Finally, excess AlMe3 reagent is critical for facilitating a reductive elimination process.
Study on steroidal saponins in crude and stir‐fried Fructus Tribuli by ultra‐high‐performance liquid chromatography‐mass spectrometry coupled with multivariate statistical analysis
Authors: Zhang Chao , Yuan Rui , Guo Fei , Shi Lei , Zhang Longfei , Sun Linlin , Wang Yingzi , Zhang Xuelan , Ma Baiping 
Published: December 2019

AbstractFructus Tribuli is a traditional Chinese medicine used clinically for many years. Crude Fructus Tribuli and stir‐fried Fructus Tribuli are recorded in the Pharmacopoeia of the People′s Republic of China. However, the differences between steroidal saponins in crude Fructus Tribuli and stir‐fried Fructus Tribuli have not been compared. In this study, ultra‐high‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry along with multivariate statistical analysis was developed to discriminate the chemical profiles and identify the steroidal saponins of crude Fructus Tribuli and stir‐fried Fructus Tribuli. Additionally, an ultra‐high‐performance liquid chromatography triple‐quadrupole mass spectrometer was used for the simultaneous quantification of nine major steroidal saponins to analyze the variations between crude Fructus Tribuli and stir‐fried Fructus Tribuli. Finally, a total of 30 steroidal saponins whose structures or contents changed significantly after processing were found and identified. The mechanism of structural transformations deduced indicated that during the stir‐frying of Fructus Tribuli, C‐22 hydroxy furostanol saponins were converted to the corresponding furostanol saponins containing C‐20‐C‐22 double bonds by dehydroxylation and deglycosylation reactions that occurred in the spirostanol saponins causing the generation of steroidal sapogenins. This study was successfully applied to the global analysis of crude Fructus Tribuli and stir‐fried Fructus Tribuli. The results of this research will be beneficial to explore the processing mechanism of Fructus Tribuli.
Ultrasound Diagnosis of Breast Lymphoma and the Identification of Breast Infiltrating Ductal Carcinoma
Authors: Chen Yang , Zhou Jie‐hong , Fan Hong‐xia , Luo Yan , Peng Yu‐lan , Ma Bu‐yun 
Published: December 2019

ObjectivesBy analyzing the B‐mode ultrasound and color Doppler flow imaging characteristics of breast lymphoma (BL) and breast infiltrating ductal carcinoma (BIDC), we expected to discriminate these diseases.MethodsThirty‐two patients with BL and 30 with BIDC confirmed pathologically were selected. The BL group was divided into nodular and diffuse groups. We analyzed and compared the general and imaging characteristics of the BL subgroups and the BIDC group.ResultsThe mean maximum diameter of BL was 54.93 ± 43.74 cm, and that of BIDC was 23.90 ± 6.79 cm (P < .05). The differences between the nodular BL and BIDC groups in a circumscribed margin (60.00% versus 20.00%), calcification (20.00% versus 53.33%), aggregation characteristics (0.00% versus 53.33%), and density (73.33% versus 10.00%) were statistically significant (P < .05). The differences between the diffuse BL and BIDC groups in calcification (6.67% versus 53.33%), aggregation characteristics (6.67% versus 53.33%) and density (40.00% versus 10.00%) were statistically significant (P < .05). The difference in a circumscribed margin (60% versus 13.33%) between the BL subgroups was statistically significant (P < .05). The blood flow signal in BL lesions was richer than that in BIDC lesions (P < .05).ConclusionsExtrasuperior‐quadrant single lesions in the BL group were larger than those in the BIDC group. The edges of the lesions in the nodular BL group were circumscribed and dense. Lesions in the diffuse BL group did not have a circumscribed margin, calcification, aggregation characteristics, or density. The blood flow signal in BL lesions was richer than that in BIDC lesions.
Near‐shore geophysical and geotechnical investigations in support of the Trieste Marine Terminal extension
Authors: Masoli Carlo Alberto , Petronio Lorenzo , Gordini Emiliano , Deponte Michele , Boehm Gualtiero , Cotterle Diego , Romeo Roberto , Barbagallo Alfio , Belletti Rinaldo , Maffione Stefano , Meneghini Fabio , Baradello Luca 
Published: December 2019

ABSTRACTThe Port of Trieste is an international hub for land and sea trade with the dynamic markets of central and eastern Europe. Thanks to its deep natural draft (about 18 m), the modern high‐capacity vessels can moor to the piers. In view of the foreseen increase in maritime traffic, this harbour is undergoing modernization in order to improve the commercial traffic capability. In this expansion plan, the container Trieste Marine Terminal, Pier VII, is seeking an extension by about 200 m. In support of this feasibility study, multidisciplinary data acquisition was conducted in order to characterize the seabed, the sub‐bottom sediments and the bedrock (flysch formation) in front of the Trieste Marine Terminal. The acquisition of high‐resolution swath bathymetry, side‐scan sonar and magnetometer data allowed a detailed analysis of the seabed conditions from an environmental and safety perspective. High‐resolution seismic reflection data enabled us to characterize the Plio‐Quaternary soft sediments and the underlying bedrock. A static underwater refraction survey was performed using hydrophone array deployed on the sea bottom to obtain seismic velocities and to achieve a reliable time‐to‐depth conversion of reflection seismic data by first‐arrival tomographic inversion. In addition to geophysical investigations, 11 offshore boreholes were drilled for detailed logging. In situ standard penetration tests were performed on core samples with the use of a pocket penetrometer and pocket vane in order to obtain uniaxial compressive strength, undrained shear strength and undrained cohesion values, and assess the cohesive soils. During drilling, 17 undisturbed samples and 12 semi‐disturbed samples were extracted to perform laboratory tests for the identification of the principal geotechnical parameters. The goal was to obtain a reliable geological/geotechnical model in front of the Trieste Marine Terminal – from the seabed to the bedrock. Below the seafloor, a sequence of about 20–30 m thickness, containing Plio‐Quaternary soft sediments, overlies the flysch, which locally presents alteration with rocks of reduced quality. The geophysical–geotechnical integrated approach allowed us to identify and map the top of the bedrock and provided valuable information for planning the pier extension project.
Hepatic focal nodular hyperplasia after pediatric hematopoietic stem cell transplantation: The impact of hormonal replacement therapy and iron overload
Authors: Cattoni Alessandro , Rovelli Attilio , Prunotto Giulia , Bonanomi Sonia , Invernizzi Pietro , Perego Rosangela , Mariani Anna Maria , Balduzzi Adriana 
Published: December 2019

AbstractBackgroundThe advent of techniques for the assessment of iron overload (liver T2*‐MRI) has led to the awareness that focal nodular hyperplasia (FNH) represents a possible incidental finding after hematopoietic stem cell transplantation (HSCT), though its pathogenesis is still unclear.MethodsWe performed a retrospective analysis of the liver T2*‐MRI scans performed between 2013 and 2018 in a single pediatric HSCT Unit and recorded the number of patients with FNH (group A). Patients incidentally diagnosed with FNH at imaging performed for different clinical indications were included in group B.ResultsNine of 105 (8.6%) patients from group A were diagnosed with FNH. Group B included three patients. Overall, 12 patients were diagnosed 4.4 ± 3.1 years after HSCT. At univariate analysis, female gender (odds ratio [OR] 3.77, P = .03), moderate‐to‐severe iron overload (OR 6.97, P = .01), and hormone replacement therapy (HRT) administered for at least 6 months (OR 18.20, P = .0002) exposed patients to a higher risk of developing FNH. The detrimental effect of HRT was significant also at multivariate analysis (OR 7.93, P = .024). MRI‐T2* values in affected patients were statistically lower than healthy controls (P < .001).ConclusionsWe confirm the high incidence of FNH among transplanted pediatric patients and demonstrate the potential pathogenic role of HRT and iron overload.
Neurofibromatosis‐associated malignant peripheral nerve sheath tumors in children have a worse prognosis: A nationwide cohort study
Authors: Martin Enrico , Coert J. Henk , Flucke Uta E. , Slooff Willem‐Bart M. , van de Sande Michiel A.J. , van Noesel Max M. , Grünhagen Dirk J. , Wijnen Marc H.W.A. , Verhoef Cornelis 
Published: December 2019

AbstractBackgroundMalignant peripheral nerve sheath tumors (MPNST) are rare and aggressive non‐rhabdomyoblastic soft‐tissue sarcomas (NRSTS) in children. This study set out to investigate clinical presentation, treatment modalities, and factors associated with survival in pediatric MPNST using Dutch nationwide databases.MethodsData were obtained from the Netherlands Cancer Registry (NCR) and the Dutch Pathology Database (PALGA) from 1989 to 2017. All primary MPNSTs were collected. Demographic differences were analyzed between adult and pediatric (age ≤18 years) MPNST. In children, demographic and treatment differences between neurofibromatosis type 1 (NF1) and non‐NF1 were analyzed. A Cox proportional hazard model was constructed for localized pediatric MPNSTs.ResultsA total of 70/784 MPNST patients were children (37.1% NF1). Children did not present differently from adults. In NF1 children, tumor size was more commonly large (> 5 cm, 92.3% vs 59.1%). Localized disease was primarily resected in 90.6%, and radiotherapy was administered in 37.5%. Non‐NF1 children tended to receive chemotherapy more commonly (39.5% vs 26.9%). Overall, estimated five‐year survival rates of localized NF1‐MPNST was 52.4% (SE: 10.1%) compared with 75.8% (SE: 7.1%) in non‐NF1 patients. The multivariate model showed worse survival in NF1 patients (HR: 2.98; 95% CI, 1.17‐7.60, P = 0.02) and increased survival in patients diagnosed after 2005 (HR: 0.20; 95% CI, 0.06‐0.69, P = 0.01). No treatment factors were independently associated with survival.ConclusionPediatric MPNSTs have presentations similar to adult MPNSTs. In children, NF1 patients present with larger tumors, but are treated similarly to non‐NF1 MPNSTs. In localized pediatric MPNST, NF1 is associated with worse survival. Promisingly, survival has increased for pediatric MPNSTs after 2005.
Ballistic behavior of multiwalled carbon nanotube‐reinforced toughened polycarbonate nanocomposites
Authors: Bagotia Nisha , Sharma Durlubh Kumar 
Published: December 2019

AbstractThe overall goal of this research is to develop a material that is able to absorb mechanical shocks. Polycarbonate/ethylene methyl acrylate‐multiwalled carbon nanotube (PC/EMA‐MWCNTs) nanocomposites have been prepared using the melt‐blending method using a micro compounder, and their dynamic impact behavior has been studied. A Split Hopkinson pressure bar instrument has been used for dynamic impact testing of the nanocomposite samples. The impact tests were performed under varying strain rates ranging from 100 to 10 000 seconds−1. The present study reports the stress‐strain properties of PC/EMA‐MWCNTs nanocomposites under a high strain rate. Stress tolerance of these nanocomposites was studied to analyze the effectiveness of small amounts of carbon nanotubes for impact/stress absorption in comparison to pure polycarbonate (PC) and polycarbonate/ethylene methyl acrylate [PC/EMA (95/5 wt/wt)] blend samples. It is found that, at concentration levels of 5 phr of MWCNTs, the impact absorption of composites sample increased by 130% and 76% compared to pure PC and PC/EMA (95/5 wt/wt) blend, respectively.
Hexameric structure of the ATPase motor subunit of magnesium chelatase in chlorophyll biosynthesis
Authors: Gao Yong‐Shan , Wang Yan‐Li , Wang Xiao , Liu Lin 
Published: December 2019

AbstractMagnesium chelatase (MgCh) is a heterotrimeric enzyme complex, composed of two AAA+ family subunits that can assembly into a double ring structure and a large catalytic subunit. The small AAA+ subunit has ATPase activity and can self‐oligomerize into a ring structure, while the other AAA+ subunit lacks independent ATPase activity. Previous structural studies of the ATPase motor subunit of MgCh from a bacteriochlorophyll‐synthesizing bacterium have identified a unique ATPase clade, but the model of oligomeric assembly is unclear. Here we present the hexameric structure of the MgCh ATPase motor subunit from the chlorophyll‐synthesizing cyanobacterium Synechocystis sp. PCC 6803. This structure reveals details of how the hexameric ring is assembled, and thus provides a basis for further studying the heterotrimeric complex.
Can we characterize river corridor evolution at a continental scale from historical topographic maps? A first assessment from the comparison of four countries
Authors: García J. Horacio , Dunesme Samuel , Piégay Hervé 
Published: December 2019

AbstractNational historical map resources are assessed in four European countries to characterize river corridor features and associated channel changes, as well as identify issues limiting or promoting geomorphic assessment procedures at a continental scale. A geomorphic audit that launches potential data for diagnosis from reach to continental scales could offer a good resource for biology and ecology managers of river authorities or government agencies and engineers. The assessment compares the resources available by country in terms of period covered, spatial scale, history and chronology, and representation of the fluvial corridor features. We then applied the Historical Maps Vectorization Toolbox, initially developed for vectorizing river corridors from French maps, to detect and extract flow channels, unvegetated bars and riparian vegetation patches from historical topographical maps. We found that (a) it is difficult to apply an audit of channel changes to the whole continental scale because map legends differ between countries due to geographic and political specificity; (b) there exists an opportunity to get assessment information in all countries at reach or national scale where map resources are available; (c) the highest potential is observed in Switzerland and Belgium where there is high quality national map coverage from the 19th century; and (d) the algorithm Historical Maps Vectorization Toolbox applied to map resources works well with any of the countries, and its widespread application is encouraging.
Case notion discovery and recommendation: automated event log building on databases
Authors: de Murillas E. González López , Reijers H. A. , van der Aalst W. M. P. 
Published: December 2019

AbstractProcess mining techniques use event logs as input. When analyzing complex databases, these event logs can be built in many ways. Events need to be grouped into traces corresponding to a case. Different groupings provide different views on the data. Building event logs is usually a time-consuming, manual task. This paper provides a precise view on the case notion on databases, which enables the automatic computation of event logs. Also, it provides a way to assess event log quality, used to rank event logs with respect to their interestingness. The computational cost of building an event log can be avoided by predicting the interestingness of a case notion, before the corresponding event log is computed. This makes it possible to give recommendations to users, so they can focus on the analysis of the most promising process views. Finally, the accuracy of the predictions and the quality of the rankings generated by our unsupervised technique are evaluated in comparison to the existing regression techniques as well as to state-of-the-art learning to rank algorithms from the information retrieval field. The results show that our prediction technique succeeds at discovering interesting event logs and provides valuable recommendations to users about the perspectives on which to focus the efforts during the analysis.