bluuebunny/crossref_metadata_2025 huggingface dataset:
PROCJENE PEDAGOGA O OSPOSOBLJENOSTI ZA ISTRAŽIVANJE VASPITNO-OBRAZOVNE PRAKSE
Authors: Živanović Sanja
Published: October 2019

Stručni saradnici, pedagozi, učestvujuu svim fazama vaspitno-obrazovnogprocesa. Rade na planiranjui programiranju, unapređivanju i istraživanjuvaspitno-obrazovnog rada,sarađuju sa nastavnicima, roditeljima,učenicima, prate i uvodeinovacije, rade na povezivanju salokalnom i širom zajednicom, štosve upućuje na široku lepezu svesloženijih zahtjeva koji se pred njihpostavljaju i na koje moraju adekvatnoodgovoriti.Još u toku studija, budući pedagozise osposobljavaju za radne zadatke ifunkcije koje ih očekuju u vaspitno-Stručni saradnici, pedagozi, učestvujuu svim fazama vaspitno-obrazovnogprocesa. Rade na planiranjui programiranju, unapređivanju i istraživanjuvaspitno-obrazovnog rada,sarađuju sa nastavnicima, roditeljima,učenicima, prate i uvodeinovacije, rade na povezivanju salokalnom i širom zajednicom, štosve upućuje na široku lepezu svesloženijih zahtjeva koji se pred njihpostavljaju i na koje moraju adekvatnoodgovoriti.Još u toku studija, budući pedagozise osposobljavaju za radne zadatke ifunkcije koje ih očekuju u vaspitno-stavovima pedagoga o profesionalnojosposobljenosti za područje radaistraživanje vaspitno-obrazovneprakse, u odnosu na godine radnogstaža, kao i u odnosu na mjesto završenogstudija. Istraživački nalaziupućuju na postojeći kvalitet profesionalneosposobljenosti pedagoga,istrajnost u održavanju kvaliteta istog,te doslijednost različitih univerzitetau pogledu osposobljenostistručnih saradnika za navedenopodručje rada.
Isolation and molecular characterization of the indigenous Staphylococcus aureus strain K1 with the ability to reduce hexavalent chromium for its application in bioremediation of metal-contaminated sites
Authors: Tariq Muhammad , Waseem Muhammad , Rasool Muhammad Hidayat , Zahoor Muhammad Asif , Hussain Irshad
Published: October 2019

Background

Urbanization and industrialization are the main anthropogenic activities that are adding toxic heavy metals to the environment. Among these, chromium (in hexavalent: Cr+6 and/or trivalent Cr+3) is being released abundantly in wastewater due to its uses in different industrial processes. It becomes highly mutagenic and carcinogenic once it enters the cell through sulfate uptake pathways after interacting with cellular proteins and nucleic acids. However, Cr+6 can be bio-converted into more stable, less toxic and insoluble trivalent chromium using microbes. Hence in this study, we have made efforts to utilize chromium tolerant bacteria for bio-reduction of Cr+6 to Cr+3.

Methods

Bacterial isolate, K1, from metal contaminated industrial effluent from Kala Shah Kaku-Lahore Pakistan, which tolerated up to 22 mM of Cr6+ was evaluated for chromate reduction. It was further characterized biochemically and molecularly by VITEK®2 system and 16S rRNA gene sequencing respectively. Other factors affecting the reduction of chromium such as initial chromate ion concentration, pH, temperature, contact-time were also investigated. The role of cellular surface in sorption of Cr6+ ion was analyzed by FTIR spectroscopy.

Results

Both biochemical and phylogenetic analyses confirmed that strain K1 was Staphylococcusaureus that could reduce 99% of Cr6+ in 24 hours at 35 °C (pH = 8.0; initial Cr6+ concentration = 100 mg/L). FTIR results assumed that carboxyl, amino and phosphate groups of cell wall were involved in complexation with chromium. Our results suggested that Staphylococcusaureus K1 could be a promising gram-positive bacterium that might be utilized to remove chromium from metal polluted environments.
Slowed vertical saccades as a hallmark of hereditary spastic paraplegia type 7
Authors: Milenkovic Ivan , Klotz Sigrid , Zulehner Gudrun , Sycha Thomas , Wiest Gerald
Published: October 2019

Anecdotal oculomotor disturbances have been described in spastic paraplegia type 7 (SPG7). We investigated oculomotor and vestibular dysfunction in five patients with genetically verified SPG7. All five patients exhibited significantly slower velocities of vertical saccades compared to controls, but significantly faster than in progressive supranuclear palsy, with upward saccades being particularly affected. Horizontal saccades, cerebellar oculomotor markers, and vestibuloocular reflex seem to be variably affected. Thus, albeit subclinical in some cases, slowing of the vertical saccades may belong to the phenotype of SPG7 and may serve as a valuable biomarker for differentiation from spastic ataxias and atypical parkinsonism.
Bill to deregulate buprenorphine raises concerns among OTPs
Authors: Knopf Alison
Published: October 2019

The Mainstreaming Addiction Treatment Act (H.R. 2482) would deregulate buprenorphine. Adminstration of the medication is held to high standards when used in the treatment of opioid use disorder, like methadone. Also like methadone, those standards don't apply when the medication is used to treat pain. The bill only applies to buprenorphine.
Recent Advances in Emerging 2D Material‐Based Gas Sensors: Potential in Disease Diagnosis
Authors: Zhang Lu , Khan Karim , Zou Jifei , Zhang Han , Li Yingchun
Published: October 2019

2D materials are gaining great attention owing to their superior electrical, optical, and mechanical characteristics. In recent decades, 2D materials have demonstrated significant potential for the identification of disease‐related biomarkers based on semiconductor gas sensors. Herein, the recent progress of semiconductor gas sensors fabricated by 2D materials covering graphene, black phosphorus, transition metal dichalcogenides, MXenes, metal‐organic frameworks, metal oxide nanosheets, etc. is clearly described. First, the basic attributes of 2D materials are described, and their gas‐sensing mechanisms are also summarized. Second, the ability of 2D material‐based sensors in the detection of disease‐related gas molecules is also highlighted. Finally, some effective methods for enhancing the gas‐sensing performance of 2D materials are discussed, and the opportunities and challenges accompanying are also presented. This work could provide new avenues for material synthesis, sensor development, medical diagnosis, and the related fields.
Negative CT Contrast Agents for the Diagnosis of Malignant Osteosarcoma
Authors: Meng Xianfu , Zhang Hua , Zhang Meng , Wang Baoming , Liu Yanyan , Wang Yan , Fang Xiangming , Zhang Jiawen , Yao Zhenwei , Bu Wenbo
Published: October 2019

The current positive computed tomography (CT) contrast agents (PCTCAs) including clinical iodides, present high CT density value (CT‐DV). However, they are incapable for the accurate diagnosis of some diseases with high CT‐DV, such as osteosarcoma. Because bones and PCTCAs around osteosarcoma generate similar X‐ray attenuations. Here, an innovative strategy of negative CT contrast agents (NCTCAs) to reduce the CT‐DV of osteosarcoma is proposed, contributing to accurate detection of osteosarcoma. Hollow mesoporous silica nanoparticles, loading ammonia borane molecules and further modified by polyethylene glycol, are synthesized as NCTCAs for the diagnosis of osteosarcoma. The nanocomposites can produce H2 in situ at osteosarcoma areas by responding to the acidic microenvironment of osteosarcoma, resulting in nearly 20 times reduction of CT density in osteosarcoma. This helps form large CT density contrast between bones and osteosarcoma, and successfully achieves accurate diagnosis of osteosarcoma. Meanwhile, The NCTCAs strategy greatly expands the scope of CT application, and provides profound implications for the precise clinical diagnosis, treatment, and prognosis of diseases.
Ultrasensitive Multifunctional Magnetoresistive Strain Sensor Based on Hair‐Like Magnetization‐Induced Pillar Forests
Authors: Ding Li , Pei Lei , Xuan Shouhu , Fan Xiwen , Cao Xufeng , Wang Yu , Gong Xinglong
Published: October 2019

An ultrasensitive multifunctional sensor which integrates tactile sensing and magnetism sensing together in one device is presented. The sensor, dubbed L‐MPF, consists of two interlocking hair‐like magnetization‐induced pillar forests, which are self‐formed under a magnetic field and a loading pressure. An L‐MPF endows intelligent electronics with magnetic field reception, which is the sense of bacteria, birds, and whales, rather than human beings. It is found that the L‐MPF precisely detects the magnitude and the loading path of the dynamic load, including pressure, shear, and magnetic field, with fast response, high reversibility, excellent sensitivity, and high stability. The sensitivity coefficient can reach 1965, 1.6, and 240% T−1 under 50–60% compressive strain, 0–3.4° shear strain, and 21–170 mT magnetic field. Additionally, the strain sensitivity coefficient can be set by the external magnetic field, which affords a potential approach to realize different sensing requirements in various circumstances. For a detailed insight into the sensing element's behavior, the magnetic–mechanic–electric coupling response is also described by simplified model simulation and theoretical analysis. Furthermore, a 4 × 4 L‐MPF array exhibits contactless gesture sensing, which provides a new way for next‐generation human–electronics interface devices and artificial electronic skin.
A Straightforward One‐Step Access to Ticlopidine Derivatives Arylated at the C5‐Position of the Thienyl Ring via Pd‐Catalyzed Direct Arylations
Authors: Atoui Dhieb , Li Haoran , Ben Salem Ridha , Roisnel Thierry , Soulé Jean‐François , Doucet Henri
Published: October 2019

The reactivity of Ticlopidine, which belongs to the thienopyridine drug family, in Pd‐catalyzed C−H bond functionalization was investigated. The use of a palladium‐diphosphine catalyst associated to potassium acetate base in N,N‐dimethylacetamide was found to promote the regioselective arylation at the C5‐position of the Ticlopidine thienyl ring with aryl bromides in high yields. In the course of this reaction, no dechlorination or debenzylation of the 2‐chlorobenzyl group of Ticlopidine was observed. A wide variety of substituents on the aryl bromide was tolerated, such as nitro, nitrile, acetyl, propionyl, benzoyl, ester, chloro, fluoro or trifluoromethyl. Bromopyridines and bromoquinolines were also successfully employed. This methodology gives a one‐step access to arylated Ticlopidine derivatives from commercially available compounds via a straightforward C−H bond functionalization procedure. Therefore, it provides a very appealing method to build a library of compounds containing a Ticlopidine unit.
Polar‐Functionalized, Crosslinkable, Self‐Healing, and Photoresponsive Polyolefins
Authors: Zou Chen , Chen Changle
Published: October 2019

The nonpolar nature of polyolefins is one of their biggest limitations. Now, an efficient route to generate polar‐functionalized, crosslinkable, self‐healing, photoresponsive polyolefins with thermoplastic, elastomeric, and thermosetting properties is reported. Tunable amounts of carboxylic acid and a cyclic comonomer are installed onto polyolefins by palladium‐catalyzed terpolymerization reactions. The incorporated carboxylic acid unit can alter the surface properties of polyolefins. The subsequently introduced Fe3+/citric acid combination induces dynamic crosslinking and enables self‐healing. Under UV light irradiation, citric acid reduces Fe3+ to Fe2+ and decreases the crosslinking density. The Fe2+ moiety can be easily oxidized back to Fe3+, making the process reversible at the expense of citric acid. The incorporated cyclic comonomer modulates the crystallinity of polyolefins, provides elastic properties, and installs carbon–carbon double bonds for sulfur‐induced vulcanization.
Thermal gelation modeling of a pluronic‐alginate blend following coronary angioplasty
Authors: Milocco Alessio , Scuor Nicola , Lughi Vanni , Lamberti Gaetano , Barba Anna Angela , Divittorio Rosario , Grassi Gabriele , Perkan Andrea , Grassi Mario , Abrami Michela
Published: October 2019

To overcome the complications connected to the treatment of coronary atherosclerosis by means of percutaneous transluminal angioplasty followed by stent implantation, the in situ release of antiproliferative nucleic acid based drugs (NABD) seems a promising approach. For their fragile nature, NABD cannot be released from drug eluting stents but they need to be embedded in a soft gel coating the coronary wall (endoluminal gel paving). This article deals with the thermal fate, once in the catheter, of a polymer blend composed by pluronic, giving rise to a soft gel in water upon temperature rise, and alginate, a natural polysaccharide giving origin to a strong gel in the presence of divalent cations. Simulations reveal that while the formation of a pregel is rapidly achieved, the formation of a mature gel takes a much longer time with respect to the residence time of the polymer blend inside the catheter. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48539.
Flexible poly(styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene) nanocomposites for electromagnetic interference shielding
Authors: Pan Jingkai , Yue Jia , Bao Jianjun
Published: October 2019

In this report, multiwalled carbon nanotubes (CNT) embedded poly(styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene) (SEBS) microspheres (CNT/SEBS) were prepared by solvent evaporation method. Reduced graphene oxide (rGO) nanosheets were used to cover the surface of CNT/SEBS microspheres. The CNT/SEBS/rGO nanocomposites with special segregated conductive network were fabricated by hot pressing these as‐prepared complex microspheres. The morphology, electrical percolation threshold, electrical conductivity, and electromagnetic interference (EMI) shielding effectiveness (SE) of CNT/SEBS/rGO composites were characterized. The shielding mechanisms were discussed in detail. Analysis of electrical conductive performance shows that the electrical percolation threshold of rGO is 0.22 vol %. Results of EMI shielding test confirmed the synergistic effect between CNT and rGO. The EMI SE of the composite filled by 2.1 vol % CNT and 3.35 vol % rGO can achieve 26 dB in 8.2−12.4 GHz (X band), which exceeds the basic requirement for commercial application (20 dB). Its reflectance coefficient (19–41%) indicates that the most part of incident electromagnetic (EM) wave energy is attenuated through absorption mechanism. This kind of absorptive EMI shielding material can be applied without serious secondary EM radiation pollution problems. The effects of filler content, molding temperature on EMI SE, and shielding mechanism were also investigated. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48542.
Oxygen barrier, free volume, and blending properties of fully bio‐based polyamide 11/poly(vinyl alcohol) blends
Authors: Huang Ya‐qiong , Dai Dan‐dan , Li Hong‐bo , Sun Lei , Runt James , Huang Kuo‐shien , Yeh Jen‐taut
Published: October 2019

Fully bio‐based polyamide 11 (PA11) was melt‐blended with poly(vinyl alcohol) (PVA) with varying degrees of polymerization (DP) to prepare PA11xPVAzy. The PA11xPVAzy films demonstrated the lowest oxygen transmission rates (OTR) and free volume characteristics, when PVA contents of each PA11xPVAzy series reached a corresponding critical concentration. The minimum OTR and free volume characteristics obtained for the optimal PA11xPVAzy films reduced significantly with decreasing PVA DPs. The OTR of the optimal PA11xPVAzy blown film was 1.07 cm3 m−2 day−1 atm−1, which is near to that of the ethylene‐vinyl alcohol copolymer high‐barrier polymer. The results of dynamical, mechanical, and other experimental characterizations demonstrated that PA11 and PVA are compatible to some extent when PVA concentrations are less‐than or equal to the respective critical values. The enhanced oxygen permeation resistance and free volume characteristics for optimal PA11xPVAzy films are at least partly ascribed to the improved hydrogen‐bonded molecular interactions between PA11 CO groups and PVA O─H groups. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48562.
Satellite temperature measurement in LEO and improvement method of temperature sensors calibration based on the measured data
Authors: Sieger Ladislav , Nentvich Ondrej , Urban Martin
Published: October 2019

This article describes the temperature measurement and its calibration on board of the nanosatellite CubeSat class VZLUSAT‐1. There are several thermometers, installed with an analog and a digital output, which are necessary for the accurate measurements calibrations under a vacuum condition or for applying postprocessing corrections. This document describes the way of calibration in a thermal vacuum chamber and its improvement in orbit. In addition, this article will discuss the use of a resistance temperature detector platinum sensors Pt1000 and a digital sensors HYT271 as the reference. A correction variable based on HYT271 compensates a nonlinearity of Pt1000 as well as minimizes the influence of change in a measuring current due to temperature changes. The current correction variable is a function of temperature and nanosatellite's position in the orbit. The measured temperatures are below −70°C in the Earth's shadow and greater than +80°C after irradiation by the Sun. Orbital temperature calibration is performed in two steps. The raw temperature data obtained during the orbital measurement are being used for further improvement. The measurement cycle consists of the electronics calibration, temperature measurement, and temperature calibration. After applying the temperature correction process, the final accuracy becomes better than ±0.15°C.
Performance of a modified three-level classification in stratifying open liver resection procedures in terms of complexity and postoperative morbidity
Authors: Kawaguchi Y , Hasegawa K , Tzeng C-W D , Mizuno T , Arita J , Sakamoto Y , Chun Y S , Aloia T A , Kokudo N , Vauthey J-N
Published: October 2019

Background

Traditional classifications for open liver resection are not always associated with surgical complexity and postoperative morbidity. The aim of this study was to test whether a three-level classification for stratifying surgical complexity based on surgical and postoperative outcomes, originally devised for laparoscopic liver resection, is superior to classifications based on a previously reported survey for stratifying surgical complexity of open liver resections, minor/major nomenclature or number of resected segments.

Methods

Patients undergoing a first open liver resection without simultaneous procedures at MD Anderson Cancer Center (Houston cohort) or the University of Tokyo (Tokyo cohort) were studied. Surgical and postoperative outcomes were compared among three grades: I (wedge resection for anterolateral or posterosuperior segment and left lateral sectionectomy); II (anterolateral segmentectomy and left hepatectomy); III (posterosuperior segmentectomy, right posterior sectionectomy, right hepatectomy, central hepatectomy and extended left/right hepatectomy).

Results

In both the Houston (1878 patients) and Tokyo (1202) cohorts, duration of operation, estimated blood loss and comprehensive complication index score differed between the three grades (all P < 0·050) and increased in stepwise fashion from grades I to III (all P < 0·001). Left hepatectomy was associated with better surgical and postoperative outcomes than right hepatectomy, extended right hepatectomy and right posterior sectionectomy, although these four procedures were categorized as being of medium complexity in the survey-based classification. Surgical outcomes of minor open liver resections also differed between the three grades (all P < 0·050). For duration of operation and blood loss, the area under the curve was higher for the three-level classification than for the minor/major or segment-based classification.

Conclusion

The three-level classification may be useful in studies analysing open liver resection at Western and Eastern centres.
Improving the Activity of M−N4 Catalysts for the Oxygen Reduction Reaction by Electrolyte Adsorption
Authors: Svane Katrine L. , Reda Mateusz , Vegge Tejs , Hansen Heine A.
Published: October 2019

Metal and nitrogen codoped carbons (M−N/Cs) have emerged as promising alternatives to platinum‐based catalysts for the oxygen reduction reaction (ORR). DFT calculations are used to investigate the adsorption of anions and impurities from the electrolyte on the active site, modeled as an M−N4 motif embedded in a planar carbon sheet (M=Cr, Mn, Fe, Co). The two‐dimensional catalyst structure implies that each metal atom has two potential active sites, one on each side of the sheet. Adsorption of anions or impurities on both sites results in poisoning, but adsorption on one of the sites leads to a modified ORR activity on the remaining site. The calculated adsorption energies show that a number of species adsorb only on one of the two sites under realistic experimental conditions. Furthermore, a few of these adsorbates modify the adsorption energies of the ORR intermediates on the remaining site, in such a way that the limiting potential is improved.
Comparison of distance‐based and model‐based ordinations
Authors: Roberts David W.
Published: October 2019

Distance‐based ordinations have played a critical role in community ecology for more than half a century, but are still under active development. These methods employ a matrix of pairwise distances or dissimilarities between sample units, and map sample units from the high‐dimensional distance or dissimilarity space to a low‐dimensional representation for analysis. Distance‐ or dissimilarity‐based methods employ continuum or gradient ecological theory and a variety of statistical models to achieve the mapping. Recently, ecologists have developed model‐based ordinations based on latent vectors and individual species response models. These methods employ the individualistic perspective of Gleason as the ecological model, and Bayesian or maximum‐likelihood methods to estimate the parameters for the low dimensional space represented by the latent vectors. In this research I compared two distance‐based methods (NMDSand t‐SNE) with two model‐based methods (BORALandREO) on five data sets to determine which methods are superior for (1) extracting meaningful ecological drivers of variability in community composition, and (2) estimating sample unit locations in ordination space that maximize the goodness‐of‐fit of individual species response models to the estimated sample unit locations. Environmental variables and species were fitted to the ordinations by generalized additive models (GAMs) with Gaussian, negative binomial, or Poisson distribution models as appropriate. Across the five data sets, 22 models of environmental variability and 449 models of species distributions were calculated for each of the ordination methods. To minimize the effects of stochasticity the entire analysis was replicated three times and results averaged across the replicates. Results were evaluated by deviance explained andAICfor environmental variables and species distributions, averaged by ordination method for each data set, and ranked from best to worst. For the four assessments distance‐based methods ranked 1 and 2 in three cases, and 1 and 3 in one case, significantly out performing the model‐based methods. t‐SNEwas the top‐performing method, out performingNMDSespecially on the more complex data sets. In general the gradient‐based theoretical basis and data sufficiency of distance‐based methods allowed distance‐based methods to outperform model‐based methods in every assessment.
Mechanochromic and Electroluminescence Properties of a Layered Hybrid Perovskite Belonging to the <110> Series
Authors: Salah Maroua Ben Haj , Mercier Nicolas , Allain Magali , Zouari Nabil , Giovanella Umberto , Botta Chiara
Published: October 2019

A layered hybrid perovskite belonging to the <110> series, (FA)2(HEA)2Pb2Br8 (HEA+, hydroxyethylammonium; FA+, formamidinium) exhibits a bright green narrow emission and a reversible mechanochromic luminescence effect: after grinding the powder a few seconds, the emission is blue shifted from 500 to 480 nm due to a partial amorphization. PeLEDs based on (FA)2(HEA)2Pb2Br8 as active material were also demonstrated, which is unprecedented for such a layered hybrid perovskite.
Cooperative Effects of Aniline with DMSO in RuII Complexes: Tuning the Reactivity for Ring‐Opening Metathesis Polymerization
Authors: Martins Daniele M. , Maia Pedro I. S. , Carvalho‐Jr Valdemiro P. , Lima‐Neto Benedito S.
Published: October 2019

The complex cis,fac‐[RuCl2(DMSO–O)(DMSO–S)3] [1] reacted with aniline (NH2Ph) under reflux to produce the complex trans,cis,cis‐[RuCl2(DMSO–S)2(NH2Ph)2] [2], whereas at room temperature the resulting complex was cis,fac‐[RuCl2(DMSO–S)3(NH2Ph)] [3]. The complexes were characterized by FTIR, EPR, 1H and 13C NMR, electronic spectra, and the crystal structure of 2 was determined by single X‐ray crystallography. The influence of NH2Ph and DMSO as ancillary ligands in the new complexes was then evaluated for ring‐opening metathesis polymerization (ROMP) of norbornene (NBE), norbornadiene (NBD), and dicyclopentadiene (DCPD) in presence of ethyl diazoacetate (EDA) with different [monomer]/[Ru] molar ratios. Homopolymers of NBE with molecular weights in the order of magnitude of 105 g.mol–1 and insoluble polymers in CHCl3 from NBD and DCPD were obtained in different yields depending of the starting complex, reaction time (5 and 30 min), and temperature (25 and 50 °C). Valorous results were obtained for polyNBD, polyDCPD, and copolymerizations from NBE with NBD or DCPD using the new complexes, affording higher yields than with 1. In conclusion, beneficial effects are observed when DMSO and the weak σ‐donor NH2Ph ligands are arranged in the same coordination sphere of Ru(II) pre‐catalysts for ROMP.
Numerical analysis of performance of water‐based nanofluid flowing through tube bent at 90°
Authors: Kumar Dinesh , Sokhal Gurpreet Singh
Published: October 2019

The aim of the present study is to analyze the performance of CuO nanofluids with water as the base fluid in the flat tube bent at 90°. The analytical analysis has been performed under different Reynolds number as well as nanoparticle volume concentrations. Various thermophysical properties, that is, density, thermal conductivity, viscosity, and specific heat capacity have been estimated with well‐developed models of each, presented during previous studies carried out in the field of nanofluids. The simulation work has been performed with the help of the finite volume method. It was concluded from this study that heat transfer coefficient and Nusselt number of nanofluids at different volume concentrations between 0.1% to 0.5% v/v CuO is higher than that of the base fluids. The pressure drop obtained upon the use of nanofluids is found to be higher than the base fluid. The study also proves that nanofluids have a huge potential in playing an important role in decreasing sizes of heat transfer systems.
Discharge estimation of submarine springs in the Dead Sea based on velocity or density measurements in proximity to the water surface
Authors: Munwes Yaniv Y. , Geyer Stefan , Katoshevski David , Ionescu Danny , Licha Tobias , Lott Christian , Laronne Jonathan B. , Siebert Christian
Published: October 2019

The Dead Sea is a closed lake, the water level of which is lowering at an alarming rate of about 1 m/year. Factors difficult to determine in its water balance are evaporation and groundwater inflow, some of which emanate as submarine groundwater discharge. A vertical buoyant jet generated by the difference in densities between the groundwater and the Dead Sea brine forms at submarine spring outlets. To characterize this flow field and to determine its volumetric discharge, a system was developed to measure the velocity and density of the ascending submarine groundwater across the center of the stream along several horizontal sections and equidistant depths while divers sampled the spring. This was also undertaken on an artificial submarine spring with a known discharge to determine the quality of the measurements and the accuracy of the method. The underwater widening of the flow is linear and independent of the volumetric spring discharge. The temperature of the Dead Sea brine at lower layers primarily determines the temperature of the surface of the upwelling, produced above the jet flow, as the origin of the main mass of water in the submarine jet flow is Dead Sea brine. Based on the measurements, a model is presented to evaluate the distribution of velocity and solute density in the flow field of an emanating buoyant jet. This model allows the calculation of the volumetric submarine discharge, merely requiring either the maximum flow velocity or the minimal density at a given depth.
Prenatal diagnosis of fetal heterotaxy syndrome by ultrasound: A case report
Authors: Wang Yuan , Zhao Xu , Ge Tingting
Published: October 2019

A case report outlining the intrauterine prenatal sonographic delineation of the cardiac complex associated with heterotaxy syndrome.
Direct Derivation of Free Energies of Membrane Deformation and Other Solvent Density Variations From Enhanced Sampling Molecular Dynamics
Authors: Fiorin Giacomo , Marinelli Fabrizio , Faraldo‐Gómez José D.
Published: October 2019

We report a methodology to calculate the free energy of a shape transformation in a lipid membrane directly from a molecular dynamics simulation. The bilayer need not be homogeneous or symmetric and can be atomically detailed or coarse grained. The method is based on a collective variable that quantifies the similarity between the membrane and a set of predefined density distributions. Enhanced sampling of this “Multi‐Map” variable re‐shapes the bilayer and permits the derivation of the corresponding potential of mean force. Calculated energies thus reflect the dynamic interplay of atoms and molecules, rather than postulated effects. Evaluation of deformations of different shape, amplitude, and range demonstrates that the macroscopic bending modulus assumed by the Helfrich–Canham model is increasingly unsuitable below the 100‐Å scale. In this range of major biological significance, direct free‐energy calculations reveal a much greater plasticity. We also quantify the stiffening effect of cholesterol on bilayers of different composition and compare with experiments. Lastly, we illustrate how this approach facilitates analysis of other solvent reorganization processes, such as hydrophobic hydration. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.
FSATOOL: A useful tool to do the conformational sampling and trajectory analysis work for biomolecules
Authors: Zhang Haomiao , Gong Qiankun , Zhang Haozhe , Chen Changjun
Published: October 2019

Reliable conformational sampling and trajectory analysis are always important to the study of the folding or binding mechanisms of biomolecules. Generally, one has to prepare many complicated parameters and follow a lot of steps to obtain the final data. The whole process is too complicated to new users. In this article, we provide a convenient and user‐friendly tool that is compatible to AMBER, called fast sampling and analysis tool (FSATOOL). FSATOOL has some useful features. First and the most important, the whole work is extremely simplified into two steps, one is the fast sampling procedure and the other is the trajectory analysis procedure. Second, it contains several powerful sampling methods for the simulation on graphics process unit, including our previous mixing replica exchange molecular dynamics method. The method combines the advantages of the biased and unbiased simulations. Finally, it extracts the dominant transition pathways automatically from the folding network by Markov state model. Users do not need to do the tedious intermediate steps by hand. To illustrate the usage of FSATOOL in practice, we perform one simulation for a RNA hairpin in explicit solvent. All the results are presented. © 2019 Wiley Periodicals, Inc.
Sirt6 attenuates hypoxia‐induced tubular epithelial cell injury via targeting G2/M phase arrest
Authors: Gao Zhao , Chen Xinghua , Fan Yanqin , Zhu Kai , Shi Ming , Ding Guohua
Published: October 2019

Acute kidney injury (AKI) is a condition that has a high incidence and death rate. Unfortunately, the kidney may not recover completely after AKI, which then develops to chronic kidney disease (CKD). Therefore, it is necessary to identify potential curative targets to avoid its development to CKD. As an NAD+‐dependent deacetylase, sirtuin 6 (Sirt6) has been linked to different types of biological processes. In the present work, our group investigated the role of Sirt6 in tubular epithelial cells (TECs) under hypoxic stress. Sirt6 expression was examined in mouse kidney following ischemia/reperfusion (IR) injury and hypoxia‐challenged TECs. Using Sirt6 plasmid and small interfering RNA, we also investigated how, in regard to inflammation and epithelial‐to‐mesenchymal transition, Sirt6 affects hypoxia‐triggered injury. In addition, cell cycle was detected in hypoxia‐challenged TECs. Sirt6 was downregulated in the kidney of mice with IR injury and hypoxia‐challenged TECs. Consequently, Sirt6 depletion aggravated hypoxia‐induced injury and G2/M phase arrest. Sirt6 overexpression attenuated hypoxia‐triggered damage and G2/M phase arrest in TECs. Sirt6 prevented hypoxia‐triggered TEC damage via suppressing G2/M phase arrest. Thus, Sirt6 is a possible candidate for alleviating the effects of kidney injury.
Chlorogenic acid activates ERK1/2 and inhibits proliferation of osteosarcoma cells
Authors: Sapio Luigi , Salzillo Alessia , Illiano Michela , Ragone Angela , Spina Annamaria , Chiosi Emilio , Pacifico Severina , Catauro Michelina , Naviglio Silvio
Published: October 2019

Osteosarcoma (OS) is a very aggressive metastatic pediatric and adolescent tumor. Due to its recurrent development of chemotherapy resistance, clinical outcome for OS patients remains poor. Therefore, discovering more effective anticancer agents is needed. Chlorogenic acid (CGA) is a phenolic compound contained in plant‐related products that modulates many cellular functions and inhibits cell proliferation in several cancer types. However, few evidence is available in OS. Here, we investigate the effects of CGA in U2OS, Saos‐2, and MG‐63 OS cells. By multiple approaches, we demonstrate that CGA acts as anticancer molecule affecting the cell cycle and provoking cell growth inhibition mainly by apoptosis induction. We also provide evidence that CGA strongly activates extracellular‐signal‐regulated kinase1/2 (ERK1/2). Strikingly, ERK1/2 inhibitor PD98059 sensitizes the cells to CGA. Altogether, our data enforce the evidence of the anticancer activity mediated by CGA and provide the rationale for the development of innovative therapeutic strategies in OS cure.
The effect of gastric acid on chitosan modified glass ionomer cement: SEM‐EDS
Authors: Soygun Koray , Soygun Arzu , Dogan Muharrem Cem
Published: October 2019

This study aimed to use scanning electron microscopy with energy dispersive spectroscopy (SEM‐EDS) to examine the elements that passed into the gastric acid solution after the application of a gastric acid erosive cycle to chitosan modified glass ionomer cement (GIC). Chitosan modified GIC samples were obtained by adding chitosan (vol/vol) of 5 and 10% to GIC for the experimental groups. These two experimental groups and a control group were subjected to gastric acid erosive treatment for 60 s six times a day for 10 days. The sample surfaces were coated with approximately 1 nm of gold to increase conductivity with the Q 150R ES device (Quorum Technologies, East Sussex, England). Surface topography images were obtained with a SEM. Besides, EDS analysis was also determined the number of elements graphically in the region where the fast electron beam hit. In the samples examined, the amount of element was determined. After gastric acid application, cracks and voids were observed on the surfaces of the samples. In the EDS analysis of the 5 and 10% chitosan modified GIC and control groups, Si, Al, Na, and F was found. It is necessary to investigate the antibacterial properties and physical properties of chitosan modified glass ionomer‐free elements and fluorine ions using advanced techniques.
Risk of progression to eosinophilic esophagitis in patients with asymptomatic esophageal eosinophilia: A retrospective pilot study
Authors: Ishibashi Fumiaki , Fukushima Keita , Onizuka Ryoichi , Tanaka Ryu
Published: October 2019

Background and Aim

As the number of patients with eosinophilic esophagitis (EoE) has increased worldwide, the likelihood of diagnosing esophageal eosinophilia (EE) in screening endoscopy has also increased. Many of these EE patients do not display any symptoms (i.e. they display asymptomatic EE: aEE), and the risk of aEE patients developing EoE has yet to be demonstrated.

Methods

A total of 62 250 cases were found in the endoscopic registries of two digestive disease centers in the context of gastric cancer screening from April 2016 to August 2018, and these were reviewed.

Results

Thirty‐seven aEE patients (0.059%) were found in the registries, and the histories of endoscopic findings and symptoms were successfully traced for 29 of them. While 11 aEE (37.9%) patients did not show any change in endoscopic findings, 18 (62.1%) exhibited exacerbation. A comparison of the two groups showed both relative youth and diffuse disease distribution to be independent risk factors for progression (P = 0.0034 and 0.0078, respectively). Of the 18 aEE patients whose findings showed progression, 6 developed EoE (5 (17.2%) developed proton‐pump inhibitor (PPI)‐responsive EoE, and only 1 (3.4%) developed PPI‐resistant EoE). A comparison of the non‐EoE and EoE groups showed relative youth to be an independent risk factor for progression to EoE (P = 0.0146).

Conclusions

While some aEE patients developed symptomatic EE, the existence among them of PPI‐resistant EoE was extremely rare. Younger age and diffuse disease distribution at first detection in endoscopic findings are risk factors for progression to symptomatic EE in aEE patients.
Inborn errors of enzymes in glutamate metabolism
Authors: Rumping Lynne , Vringer Esmee , Houwen Roderick H. J. , van Hasselt Peter M. , Jans Judith J. M. , Verhoeven‐Duif Nanda M.
Published: October 2019

Glutamate is involved in a variety of metabolic pathways. We reviewed the literature on genetic defects of enzymes that directly metabolise glutamate, leading to inborn errors of glutamate metabolism. Seventeen genetic defects of glutamate metabolising enzymes have been reported, of which three were only recently identified. These 17 defects affect the inter‐conversion of glutamine and glutamate, amino acid metabolism, ammonia detoxification, and glutathione metabolism. We provide an overview of the clinical and biochemical phenotypes of these rare defects in an effort to ease their recognition. By categorising these by biochemical pathway, we aim to create insight into the contributing role of deviant glutamate and glutamine levels to the pathophysiology. For those disorders involving the inter‐conversion of glutamine and glutamate, these deviant levels are postulated to play a pivotal pathophysiologic role. For the other IEM however—with the exception of urea cycle defects—abnormal glutamate and glutamine concentrations were rarely reported. To create insight into the clinical consequences of disturbed glutamate metabolism—rather than individual glutamate and glutamine levels—the prevalence of phenotypic abnormalities within the 17 IEM was compared to their prevalence within all Mendelian disorders and subsequently all disorders with metabolic abnormalities notated in the Human Phenotype Ontology (HPO) database. For this, a hierarchical database of all phenotypic abnormalities of the 17 defects in glutamate metabolism based on HPO was created. A neurologic phenotypic spectrum of developmental delay, ataxia, seizures, and hypotonia are common in the inborn errors of enzymes in glutamate metabolism. Additionally, ophthalmologic and skin abnormalities are often present, suggesting that disturbed glutamate homeostasis affects tissues of ectodermal origin: brain, eye, and skin. Reporting glutamate and glutamine concentrations in patients with inborn errors of glutamate metabolism would provide additional insight into the pathophysiology.
A Demographic model for ring‐necked ducks breeding in Minnesota
Authors: Roy Charlotte L. , Berdeen James B. , Clark Mark
Published: October 2019

Population models can provide insights into how perturbations of demographic vital rates influence population growth rates (λ) and help prioritize efforts to achieve management goals. Although population models have been developed for numerous duck species, this tool has not been developed for ring‐necked ducks (Aythya collaris). Ring‐necked ducks are a late‐nesting species that may not be surveyed well by the May Waterfowl Survey, which is timed optimally for earlier nesting ducks like the mallard (Anas platyrhynchos). Information specific to ring‐necked ducks would help identify important influences on the rate of population growth and the direction of population change. We used data from our own research during 2008–2012, long‐term (1975–2016) survey data from northcentral Minnesota, USA, vital rate estimates from the literature, and long‐term (1987–2016) banding data to develop a population model for ring‐necked ducks. We estimated annual survival and recovery rates of after‐hatching‐year and hatching‐year female ring‐necked ducks in Minnesota. Survey results and our matrix models indicated that ring‐necked ducks are declining in the forested portion of Minnesota. Thus, we examined a boom‐or‐bust simulation scenario that might maintain a population through periodic occurrence of exceptional reproductive years in conjunction with high hatching‐year survival. Our results indicated that long‐term persistence is only expected in this population if reproductive output doubled at the same time that hatching‐year survival was at its highest value, or if the population is maintained through immigration. Sensitivity analysis indicated that unit changes in 30‐day brood survival will produce the most change in λ in the parameter space observed, although elasticity analysis indicated that proportional changes in annual survival of adult females will produce the largest proportional changes in λ. Management to improve brood survival to increase λ might include improving the habitat quality of brood‐rearing lakes, especially those with more open water and less nesting habitat than those used for nesting. Our findings might also help explain disparities between annual breeding waterfowl surveys, which indicate stable or increasing populations, and hunter experiences in the fall. In Minnesota, hunter experiences have not matched expectations based on historical fall numbers and this could occur if regional production declined and fewer young birds were available for harvest. Our findings highlight the need for further study to inform management in this rapidly changing region. © 2019 The Wildlife Society.
White‐tailed deer and coyote colonization: a response to Kilgo et al. (2019)
Authors: Bragina Eugenia V. , Kays Roland , Hody Allison , Moorman Christopher E. , DePerno Christopher S. , Mills L. Scott
Published: October 2019

We stand by our conclusion that there have not been large‐scale declines in white‐tailed deer populations following coyote colonization of the eastern United States. However, we agree that coyote predation can affect deer populations locally and therefore and should be considered in deer harvest planning in the region.
Aerodynamically driven phonation of individual vocal folds under general anesthesia in canines
Authors: Heaton James T. , Kobler James B. , Ottensmeyer Mark P. , Petrillo Robert H. , Tynan Monica A. , Mehta Daryush D. , Hillman Robert E. , Zeitels Steven M.
Published: October 2019

Objectives/Hypothesis

We previously developed an instrument called the Aerodynamic Vocal Fold Driver (AVFD) for intraoperative magnified assessment of vocal fold (VF) vibration during microlaryngoscopy under general anesthesia. Excised larynx testing showed that the AVFD could provide useful information about the vibratory characteristics of each VF independently. The present investigation expands those findings by testing new iterations of the AVFD during microlaryngoscopy in the canine model.

Study Design

Animal model.

Methods

The AVFD is a handheld instrument that is positioned to contact the phonatory mucosa of either VF during microlaryngoscopy. Airflow delivered through the AVFD shaft to the subglottis drives the VF into phonation‐like vibration, which enables magnified observation of mucosal‐wave function with stroboscopy or high‐speed video. AVFD‐driven phonation was tested intraoperatively (n = 26 VFs) using either the original instrument design or smaller and larger versions three‐dimensionally printed from a medical grade polymer. A high‐fidelity pressure sensor embedded within the AVFD measured VF contact pressure. Characteristics of individual VF phonation were compared with typical two‐fold phonation and compared for VFs scarred by electrocautery (n = 4) versus controls (n = 22).

Results

Phonation was successful in all 26 VFs, even when scar prevented conventional bilateral phonation. The 15‐mm‐wide AVFD fits best within the anteroposterior dimension of the musculo‐membranous VF, and VF contact pressure correlated with acoustic output, driving pressures, and visible modes of vibration.

Conclusions

The AVFD can reveal magnified vibratory characteristics of individual VFs during microlaryngoscopy (e.g., without needing patient participation), potentially providing information that is not apparent or available during conventional awake phonation, which might facilitate phonosurgical decision making.

Level of Evidence

NALaryngoscope, 130: 1980–1988, 2020
Sparse POD modal subsets for reduced‐order nonlinear explicit dynamics
Authors: Phalippou Pierre , Bouabdallah Salim , Breitkopf Piotr , Villon Pierre , Zarroug Malek
Published: October 2019

Projected reduced order methods (PROM) such as the proper orthogonal decomposition (POD) rely on the quality of the underlying reduced basis (RB) used to approximate the solution. The RB is generally constructed by the low‐rank approximation of a set of observations, taken from full‐scale simulations, through truncated singular value decomposition (SVD) of the snapshot matrix. This paper revisits the selection criterion of the RB functions in the study of dynamical systems. In opposition to truncating the set of left singular vectors, taken consecutively in decreasing order of associated singular values, the proposed method takes temporality into account, resulting in a compact, sparse subset of RB functions. Selection strategies, implemented in the reduced‐order version of a legacy nonlinear explicit dynamics finite element (FE) code, are compared in both offline and online phases in terms of work of internal forces reconstruction error.
An energy‐conserving and decaying time integration method for general nonlinear dynamics
Authors: Zhang H. M. , Xing Y. F. , Ji Y.
Published: October 2019

An energy‐conserving and decaying time integration method is derived from the discretized energy balance equation in this paper. Based on the Gauss‐Legendre quadrature rule, the new method evaluates the mean internal force by collecting the internal forces of several quadrature points in the time interval. Compared with previous conserving methods, the new method avoids the reconstruction of finite element models as used in the energy‐momentum method, and the computation of energy functions as used in the constraint energy method, so it is simple and straightforward, and has no difficulty in implementation for dynamics with general nonlinear resilience including nonlinear damping force and internal force. By employing enough quadrature nodes, this method can preserve system energy accurately for conservative system, and then the unconditional stability is achieved automatically. In addition, the energy‐decaying method is developed by introducing the energy dissipation term to the energy balance equation, and two free parameters controlling the numerical dissipation are determined based on linear spectral analysis. Finally, the performance of the proposed method is checked on several examples and the results are compared with that of the trapezoidal rule.