bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of highly branched polyethylene using para‐phenyl‐substituted α‐diimine nickel catalysts
Authors: Wang Fuzhou , Li Ruiping , Tian Susu , Lian Kunbo , Guo Dengfeng , Li Weimin 
Published: March 2018

A series of para‐phenyl‐substituted α‐diimine nickel complexes, [(2,6‐R2‐4‐PhC6H2N═C(Me))2]NiBr2 (R = iPr (1); R = Et (2); R = Me (3); R = H (4)), were synthesized and characterized. These complexes with systematically varied ligand sterics were used as precatalysts for ethylene polymerization in combination with methylaluminoxane. The results indicated the possibility of catalytic activity, molecular weight and polymer microstructure control through catalyst structures and polymerization temperature. Interestingly, it is possible to tune the catalytic activities ((0.30–2.56) × 106 g (mol Ni·h)−1), polymer molecular weights (Mn = (2.1–28.6) × 104 g mol−1) and branching densities (71–143/1000 C) over a very wide range. The polyethylene branching densities decreased with increasing bulkiness of ligand and decreasing polymerization temperature. Specifically, methyl‐substituted complex 3 showed high activities and produced highly branched amorphous polyethylene (up to 143 branches per 1000 C).
Comparison of graphene oxide and graphitic carbon nitride filled carbon–phenolic composites: Thermomechanical properties and role of the strong electronegativity of nanofillers
Authors: Ma Yuanyuan , Yang Yu , Lu Chunxiang , Lu Kuan , Wu Shijie , Liu Xingchen , Wen Xiaodong 
Published: March 2018

ABSTRACTCarbon–phenolic (CF–PR) composites with 0.1 wt % graphene oxide (GO) and acidified graphitic carbon nitride (ag‐C3N4) were synthesized and characterized to understand their thermal properties. The thermal conductivity, coefficient thermal expansion, dynamic mechanical analysis, and scanning electron microscopy were used in our experimental efforts. The results demonstrate that the ag‐C3N4‐filled composite had 17.17% and 54% reductions in the thermal conductivity and coefficient thermal expansion, respectively, when compared with the neat composite, although the GO‐filled showed a 8.54% decrease and a 30% increase, respectively. Furthermore, reactive molecular dynamics simulation was used to investigate the mechanisms at the atomistic level when the composites are subjected to thermal behavior. The simulated results show that the influence of GO and ag‐C3N4 on the thermal conductivities of the composites was different. Lowly loaded GO favored the more interfacial thermal resistance. However, the stronger electronegativity in ag‐C3N4 favored the formation of a vacuum zone in the matrix; this contributed to increasing the interfacial boundaries and defect scattering. The simulation results are expected to be of great help to serve as a guide for further experiments concerning the thermal properties. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46242.
Chromatic detection of glucose using polymerization of diacetylene vesicle
Authors: Kim Minhee , Shin Young Jae , Hwang Seung Won , Shin Min Jae , Shin Jae Sup 
Published: March 2018

ABSTRACTA polydiacetylene vesicle was used to fabricate glucose sensor, allowing feasible colorimetric detection. The vesicle was formed by sonication of 10,12‐pentacosadiynoic acid (PCDA). H2O2 formed by the reaction between glucose and glucose oxidase functioned as the initiator for the polymerization of PCDA in the presence of horseradish peroxidase. The solution turned blue after the polymerization of PCDA vesicle. Thus, the glucose concentration could be detected to the concentration level that turns the solution to blue. The ultraviolet absorbance of glucose solution was proportional to glucose concentration. The results of this study indicate that glucose concentration upto 1 mM can be detected by change in blue color by eyes. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46394.
Female Reproductive and Hormonal Factors and Incidence of Primary Total Knee Arthroplasty Due to Osteoarthritis
Authors: Hussain Sultana Monira , Wang Yuanyuan , Giles Graham G. , Graves Stephen , Wluka Anita E. , Cicuttini Flavia M. 
Published: March 2018

ObjectiveTo examine the associations of female reproductive and hormonal factors with incidence of total knee arthroplasty (TKA) for osteoarthritis (OA), and to determine whether the associations differ according to overweight/obesity status.MethodsThis study included 22,289 women in the Melbourne Collaborative Cohort Study. Data on age at menarche, pregnancy, parity, years of menstruation, oral contraceptive (OC) use, menopausal status, and hormone replacement therapy (HRT) were collected in 1990–1994. Incidence of TKA during 2001–2013 was determined by linking cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. All analyses were adjusted for age, body mass index (BMI) at midlife, change in BMI (from early reproductive age to midlife), country of birth, physical activity, smoking, and education level.ResultsOver the course of 12.7 years, 1,208 TKAs for OA were identified. Ever being pregnant was associated with increased risk of TKA (hazard ratio [HR] 1.32 [95% confidence interval (95% CI) 1.06–1.63]). Parity was positively associated with risk of TKA (P for trend = 0.003). OC users had increased risk of TKA compared with non‐users (for OC use of <5 years, HR 1.25 [95% CI 1.08–1.45]; for OC use of ≥5 years, HR 1.17 [95% CI 1.00–1.37]). A 1‐year increase in menstruation was associated with a 1% decrease in risk of TKA (HR 0.99 [95% CI 0.97–0.99]). These associations remained significant only in women of normal weight at early reproductive age. Current HRT users had increased risk of TKA compared with non‐users (HR 1.37 [95% CI 1.14–1.64]); the association was significant only in non‐obese women at midlife.ConclusionReproductive and hormonal factors were associated with risk of knee OA. These associations remained significant in women of normal weight at early reproductive age and in non‐obese women at midlife. Further work is needed to understand the complex effect of these factors on knee OA.
Virtualization for computer networking skills development in a distance learning environment
Authors: Donelan Helen , Smith Andrew , Wong Patrick 
Published: March 2018

AbstractVirtualization is a core technology for teaching networking and operating system skills. In a distance learning, or e‐learning, environment, the use of virtualization presents different challenges—both technical and pedagogical. In the initiative presented here, distance learning students studying a module on computer networking and server technologies were required to install virtual machines on their own computers in order to carry out practical labs originally designed for a classroom environment. This research explores and evaluates the strategies developed to support students via a survey of students completing the module. The findings show that the majority of students found it a valuable learning experience and developed practical skills relevant to computer networking careers. Recommendations are made to inform the future development of courses considering the use of virtual machines installed on students’ machines to enable practical labs to be undertaken at a distance.
Rigid Peptide Macrocycles from On‐Resin Glaser Stapling
Authors: Cistrone Philip A. , Silvestri Anthony P. , Hintzen Jordi C. J. , Dawson Philip E. 
Published: March 2018

AbstractPeptide macrocycles are widely utilized in the development of high affinity ligands, including stapled α‐helices. The linear rigidity of a 1,3‐diynyl linkage provides an optimal distance (7 Å) between β‐carbons of the i,i+4 amino acid side chains, thus suggesting its utility in stabilizing α‐helical structures. Here, we report the development of an on‐resin strategy for an intramolecular Glaser reaction between two alkyne‐terminated side chains by using copper chloride, an essential bpy‐diol ligand, and diisopropylethylamine at room temperature. The efficiency of this ligation was illustrated by the synthesis of (i,i+4)‐, (i,i+5)‐, (i,i+6)‐, and (i,i+7)‐stapled BCL‐9 α‐helical peptides using the unnatural amino acid propargyl serine. Overall, this procedurally simple method relies on inexpensive and widely available reagents to generate low molecular weight 23‐, 26‐, 29‐, and 32‐membered peptide macrocycles.
Observational study of laryngoscopy plus flow‐volume loops during exercise
Authors: Pianosi Paolo T. , Orbelo Diana M. , Cofer Shelagh A. 
Published: March 2018

Key Clinical MessageLaryngoscopy is the gold standard to diagnose exercise‐induced laryngeal obstruction, though inspiratory flow‐volume loop may provide a clue. We combined tidal flow‐volume loop analysis plus laryngoscopy during exercise and found that cigar‐shaped – not flattened – inspiratory loops are associated with obstruction. Pursed‐lip breathing slows inhalation thereby reducing vocal fold adduction.
The Dynamics of Chemical Reactions: Atomistic Visualizations of Organic Reactions, and Homage to van ’t Hoff
Authors: Yang Zhongyue , Houk K. N. 
Published: March 2018

AbstractJacobus Henricus van ’t Hoff was the first Nobel Laureate in Chemistry. He pioneered in the study of chemical dynamics, which referred at that time to chemical kinetics and thermodynamics. The term has evolved in modern times to refer to the exploration of chemical transformations in a time‐resolved fashion. Chemical dynamics has been driven by the development of molecular dynamics trajectory simulations, which provide atomic visualization of chemical processes and illuminate how dynamic effects influence chemical reactivity and selectivity. In homage to the legend of van ’t Hoff, we review the development of the chemical dynamics of organic reactions, our area of research. We then discuss our trajectory simulations of pericyclic reactions, and our development of dynamic criteria for concerted and stepwise reaction mechanisms. We also describe a method that we call environment‐perturbed transition state sampling, which enables trajectory simulations in condensed‐media using quantum mechanics and molecular mechanics (QM/MM). We apply the method to reactions in solvent and in enzyme. Jacobus Henricus van ’t Hoff (1852, Rotterdam–1911, Berlin) received the Nobel Prize for Chemistry in 1901 “in recognition of the extraordinary services he has rendered by the discovery of the laws of chemical dynamics and osmotic pressure in solutions”. van ’t Hoff was born the Netherlands, and earned his doctorate in Utrecht in 1874. In 1896 he moved to Berlin, where he was offered a position with more research and less teaching. van ’t Hoff is considered one of the founders of physical chemistry. A key step in establishing this new field was the start of Zeitschrift für Physikalische Chemie in 1887.
Improvement of Photodynamic Activity of Lipid–Membrane‐Incorporated Fullerene Derivative by Combination with a Photo‐Antenna Molecule
Authors: Antoku Daiki , Satake Shuhei , Mae Tomoya , Sugikawa Kouta , Funabashi Hisakage , Kuroda Akio , Ikeda Atsushi 
Published: March 2018

AbstractThe weak absorbance of pristine C60, C70, and fullerene derivatives at wavelengths over 600 nm hampers the use of these molecules as photosensitizers (PSs) for photodynamic therapy (PDT). The coexistence of light‐harvesting antenna molecules with a fullerene derivative in lipid membrane bilayers solved this issue. By controlling the location of the C60 derivative in the lipid membrane, the liposomal dyad system for PDT improved the photodynamic activity via an efficient photoenergy transfer from antenna molecules to the fullerene derivative. The photodynamic activity was found to be much higher than those of dyad systems using pristine C60 and C70.
An Alumino‐Mannich Reaction of Organoaluminum Reagents, Silylated Amines, and Aldehydes
Authors: Tarasewicz Anika , Ensan Deeba , Batey Robert A. 
Published: March 2018

AbstractA multi‐component coupling using organoaluminum reagents, silylated amines, and aldehydes results in the formation of tertiary amines. Both alkenyl‐ and alkylaluminum reagents undergo reaction with iminium ion substrates for which the corresponding Petasis borono‐Mannich reactions are unsuccessful.
Characterization of metastatic urothelial carcinoma via comprehensive genomic profiling of circulating tumor DNA
Authors: Agarwal Neeraj , Pal Sumanta K. , Hahn Andrew W. , Nussenzveig Roberto H. , Pond Gregory R. , Gupta Sumati V. , Wang Jue , Bilen Mehmet A. , Naik Gurudatta , Ghatalia Pooja , Hoimes Christopher J. , Gopalakrishnan Dharmesh , Barata Pedro C. , Drakaki Alexandra , Faltas Bishoy M. , Kiedrowski Lesli A. , Lanman Richard B. , Nagy Rebecca J. , Vogelzang Nicholas J. , Boucher Kenneth M. , Vaishampayan Ulka N. , Sonpavde Guru , Grivas Petros 
Published: March 2018

BACKGROUNDBiomarker‐guided clinical trials are increasingly common in metastatic urothelial carcinoma (mUC), yet patients for whom contemporary tumor tissue is not available are not eligible. Technological advancements in sequencing have made cell‐free circulating DNA (cfDNA) next‐generation sequencing (NGS) readily available in the clinic. The objective of the current study was to determine whether the genomic profile of mUC detected by NGS of cfDNA is similar to historical tumor tissue NGS studies. A secondary objective was to determine whether the frequency of genomic alterations (GAs) differed between lower tract mUC (mLTUC) and upper tract mUC (mUTUC).METHODSPatients from 13 academic medical centers in the United States who had a diagnosis of mUC between 2014 and 2017 and for whom cfDNA NGS results were available were included. cfDNA profiling was performed using a commercially available platform (Guardant360) targeting 73 genes.RESULTSOf 369 patients with mUC, 294 were diagnosed with mLTUC and 75 with mUTUC. A total of 2130 GAs were identified in the overall mUC cohort: 1610 and 520, respectively, in the mLTUC and mUTUC cohorts. In the mLTUC cohort, frequently observed GAs were similar between cfDNA NGS and historical tumor tissue studies, including tumor protein p53 (TP53) (P = 1.000 and .115, respectively), AT‐rich interaction domain 1A (ARID1A) (P = .058 and .058, respectively), phosphatidylinositol‐4,5‐bisphosphate 3‐kinase catalytic subunit alpha (PIK3CA) (P = .058 and .067, respectively), erb‐b2 receptor tyrosine kinase 2 (ERBB2) (P = .565 and .074, respectively), and fibroblast growth factor receptor 3 (FGFR3) (P = .164 and .014, respectively). No significant difference was observed with regard to the frequency of GAs between patients with mLTUC and mUTUC.CONCLUSIONSAmong patients with mUC for whom no tumor tissue was available, cfDNA NGS was able to identify a similar profile of GAs for biomarker‐driven clinical trials compared with tumor tissue. Despite the more aggressive clinical course, cases of mUTUC demonstrated a circulating tumor DNA genomic landscape that was similar to that of mLTUC. Cancer 2018;124:2115‐24. © 2018 American Cancer Society.
Understanding the Effect of Solvent on the Growth and Crystal Morphology of MTNP/CL‐20 Cocrystal Explosive: Experimental and Theoretical Studies
Authors: Zhu Shuang‐fei , Zhang Shu‐hai , Gou Rui‐jun , Wu Chun‐lei , Han Gang , Jia Hong‐yun 
Published: March 2018

AbstractThe cocrystal of 1‐methyl‐3,4,5‐trinitro‐1H‐pyrazole (MTNP) and 2,4,6,8,10,12‐hexanitrohexaazaisowurtzitane (CL‐20) is prepared in ethanol and investigated through molecular dynamic and quantum chemistry methods. In order to study the solvent effect on the growth and crystal morphology of the cocrystal, MTNP/CL‐20‐solvent and MTNP/CL‐20‐solution interfacial models are constructed and simulated at temperatures ranging from 293 to 323 K. The analyses of polarity and absorption energy show that ethanol molecules have a larger influence on (0 ‐2 0) and (0 2 0) growth surfaces than other faces at each temperature and the predicting and experimental crystal morphologies are similar. By analyzing the binding energy of MTNP/CL‐20‐solution models, it is clear that MTNP and CL‐20 molecules are easier to be adsorbed on the growth surfaces than ethanol in the solution, and the results of cooperativity effect show that the MTNP binding to CL‐20 is tighter in the presence of ethanol. Those are perhaps the reasons why crystals with good quality were obtained from the ethanol solvent.
A fault‐tolerant modular multilevel inverter topology
Authors: Santosh Kumar Maddugari , Borghate Vijay B. , Karasani Raghavendra Reddy , Sabyasachi Sidharth , Suryawanshi Hiralal M. 
Published: March 2018

SummaryMultilevel inverter topologies have received an increasing importance for their modular structures with better integration of renewable energy sources and reduced filtering requirements. But reliability is compromised in the process of decreasing the number of switches to produce the maximum number of voltage levels. This paper elevates a single‐phase fault‐tolerant inverter topology, which is modular in structure. The proposed inverter is analyzed for open‐ or short‐circuit faults in sources and open‐circuit faults in switches. Sine Pulse Width Modulation with multicarriers technique is used to control the circuit. The carrier signals are reconfigured under fault conditions based on levels to be generated by bypassing the faulted switch or source. The circuit is simulated in MATLAB/SIMULINK, and experimental setup is developed to claim the fault tolerance of proposed inverter.
Cancer risk and clinicopathological characteristics of thyroid nodules harboring thyroid‐stimulating hormone receptor gene mutations
Authors: Mon Sann Y. , Riedlinger Gregory , Abbott Collette E. , Seethala Raja , Ohori N. Paul , Nikiforova Marina N. , Nikiforov Yuri E. , Hodak Steven P. 
Published: March 2018

BackgroundThyroid‐stimulating hormone receptor (TSHR) gene mutations play a critical role in thyroid cell proliferation and function. They are found in 20%‐82% of hyperfunctioning nodules, hyperfunctioning follicular thyroid cancers (FTC), and papillary thyroid cancers (PTC). The diagnostic importance of TSHR mutation testing in fine needle aspiration (FNA) specimens remains unstudied.MethodsTo examine the association of TSHR mutations with the functional status and surgical outcomes of thyroid nodules, we evaluated 703 consecutive thyroid FNA samples with indeterminate cytology for TSHR mutations using next‐generation sequencing. Testing for EZH1 mutations was performed in selected cases. The molecular diagnostic testing was done as part of standard of care treatment, and did not require informed consent.ResultsTSHR mutations were detected in 31 (4.4%) nodules and were located in exons 281‐640, with codon 486 being the most common. Allelic frequency ranged from 3% to 45%. Of 16 cases (12 benign, 3 FTC, 1 PTC) with surgical correlation, 15 had solitary TSHR mutations and 1 PTC had comutation with BRAF V600E. Hyperthyroidism was confirmed in all 3 FTC (2 overt, 1 subclinical). Of 5 nodules with solitary TSHR mutations detected at high allelic frequency, 3 (60%) were FTC. Those at low allelic frequency (3%‐22%) were benign. EZH1 mutations were detected in 2 of 4 TSHR‐mutant malignant nodules and neither of 2 benign nodules.ConclusionWe report that TSHR mutations occur in ∼5% thyroid nodules in a large consecutive series with indeterminate cytology. TSHR mutations may be associated with an increased cancer risk when present at high allelic frequency, even when the nodule is hyperfunctioning. Benign nodules were however most strongly correlated with TSHR mutations at low allelic frequency.
The description and number of undiscovered mammal species
Authors: Fisher Molly A. , Vinson John E. , Gittleman John L. , Drake John M. 
Published: March 2018

AbstractGlobal species counts are a key measure of biodiversity and associated metrics of conservation. It is both scientifically and practically important to know how many species exist, how many undescribed species remain, and where they are found. We modify a model for the number of undescribed species using species description data and incorporating taxonomic information. We assume a Poisson distribution for the number of species described in an interval and use maximum likelihood to estimate parameter values of an unknown intensity function. To test the model's performance, we performed a simulation study comparing our method to a previous model under conditions qualitatively similar to those related to mammal species description over the last two centuries. Because our model more accurately estimates the total number of species, we predict that 5% of mammals remain undescribed. We applied our model to determine the biogeographic realms which hold these undescribed species.
In‐plane quasi‐static cyclic tests of nonstructural lightweight steel drywall partitions for seismic performance evaluation
Authors: Pali Tatiana , Macillo Vincenzo , Terracciano Maria Teresa , Bucciero Bianca , Fiorino Luigi , Landolfo Raffaele 
Published: March 2018

SummaryAn experimental program was performed for evaluating the seismic response and fragilities of nonstructural lightweight steel drywall partitions, also considering the interaction with structural elements and other nonstructural building components, ie, outdoor façade walls. Therefore, in‐plane quasi‐static reversed cyclic tests were carried out on 8 specimens of indoor partition walls infilled in a frame and on 4 specimens of indoor partition walls connected at its ends with transversal outdoor façade walls. Constructive parameters under investigation include type of connections used for connecting the indoor partition walls to the surrounding elements, stud spacing, type of sheathing panels, and type of jointing finishing. The effect of the constructive parameters on the lateral response in secant stiffness and strength is examined. Furthermore, the main damage phenomena observed during the tests are reported and associated to 3 damage limit states distinguished for the required repair level for the tested partition walls. Fragility curves are used for the experimental assessment of seismic fragility of the tested specimens, in accordance with the interstorey drift limits required by the European code. Finally, the quantitative estimation of the repair action costs starting from the damage observation is also developed. The obtained results could be considered a starting point for developing the in‐plane seismic design assisted by testing of lightweight steel drywall partition walls.
Investigating piwi‐interacting RNA regulome in human neuroblastoma
Authors: Roy Jyoti , Mallick Bibekanand 
Published: March 2018

AbstractRemarkable attempts have been exercised in recent years using high‐throughput technologies to identify and decipher the functions of piRNAs in various abnormalities like cancer. However, piRNAs in the oncogenesis of neuroblastoma (NB) has not been reported yet even after their illustrated roles in neurological processes. Therefore, we investigated the piRNA transcriptome in IMR‐32 and SH‐SY‐5Y NB cell lines by employing high‐throughput next‐generation sequencing after confirming the expression of three associated PIWILs both at mRNAs and protein level by qRT‐PCR and immunofluroscence, respectively. We identified a common pool of 525 piRNAs of 26–32 nts long expressed in both the cell lines. The possible functions of these piRNAs were charted by predicting their targeting on retrotransposon‐containing 1769 mRNAs differentially expressed in 39 NB cell lines followed by network and pathway analysis. The analysis revealed that majority of the target binding sites in NB fall within retrotransposons residing within the 3′UTR of target mRNA transcripts like miRNA‐targets. Further, we validated the expression of key piRNAs and their target genes enriched in cancer‐related networks, pathways and biological processes which are hypothesized to play crucial roles in neoplastic events of NB. We believe that the evidence of piRNAs in human NB and their possible contribution to its pathogenesis reported in this work will open up new exciting possibilities for piRNA‐mediated therapeutics for this malignancy.