bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and Experimental Validation of a Piezoelectric Harvester with Enhanced Frequency Bandwidth
Authors: Abramovich Haim , Har-nes Idan
Published: July 2018

The use of a single bimorph as a harmonic oscillator aimed at harvesting vibrational energy is not effective due to its inherent narrow frequency bandwidth stemming from the need to adjust the natural frequency of the harvester to the platform excitation frequencies. Therefore, the present research focuses on the development, manufacturing, and testing of an advanced system based on three bimorphs, capable of adjusting their natural frequencies using tip end masses, and interconnected by springs, thus enlarging the system’s bandwidth. An analytical model was developed for three bimorphs interconnected by two springs with three end masses. The model can predict the output generated voltage from each bimorph, and then the total output power is measured on a given outside resistor as a function of the material properties, the geometric dimensions of the vibrating beams, the end-masses, and the spring constants. The analytical model was then compared with data in the literature, yielding a good correlation. To further increase the reliability of the model, a test set-up was designed and manufactured that included three bimorphs with three end-masses connected by two springs. The system was excited using a shaker, and the output voltage was measured for each bimorph for various configurations. Then, the analytical model was tuned based on the test results by introducing two factors, the quality and the stiffness factors, and the predictions of the calibrated analytical model were compared with the experimental results, yielding a good correlation. The calibrated analytical model was then used to perform a comprehensive parametric investigation for two and three bimorphs systems, in which the influences of various parameters—like spring constant, mass value, thickness, and width and length of the bimorph and the substrate beam—on the output generated power were investigated. The main conclusion from this parametric investigation was that by correctly choosing the geometric sizes of the cantilevers, the adequate tip end masses, and the ratio between constants of the springs, the frequency bandwidth is expanded yielding a higher harvested power. Typical harvested power of the present designed system can reach up to 20 mW at the first natural frequency and up to 5 mW for the second natural frequency.
Combination of Vancomycin and Cefazolin Lipid Nanoparticles for Overcoming Antibiotic Resistance of MRSA
Authors: Bhise Ketki , Sau Samaresh , Kebriaei Razieh , Rice Seth A. , Stamper Kyle C. , Alsaab Hashem O. , Rybak Michael J. , Iyer Arun K.
Published: July 2018

Vancomycin is the treatment of choice for infections caused by methicillin-resistant Staphylococcus aureus (MRSA). Clinically, combinations of vancomycin (VAN) and beta-lactams have been shown to improve patient outcomes compared to VAN alone for the treatment of MRSA bloodstream infections. However, VAN is known to cause nephrotoxicity, which could be ameliorated using biocompatible lipid drug delivery systems or liposomes. Previous attempts have been made for encapsulation of VAN in liposomes; however, drug loading has been poor, mainly because of the high aqueous solubility of VAN. In this study, we report a robust method to achieve high loading of VAN and cefazolin (CFZ) in unilamellar liposomes. Liposomes of sizes between 170–198 nm were prepared by modified reverse phase evaporation method and achieved high loading of 40% and 26% (weight/weight) for VAN and CFZ, respectively. Liposomal VAN reduced minimum inhibitory concentration (MIC) values 2-fold in comparison to commercial VAN. The combination of liposomal VAN (LVAN) and liposomal CFZ (LCFZ) demonstrated a 7.9-fold reduction compared to LVAN alone. Rhodamine dye-loaded liposomes demonstrated superior cellular uptake in macrophage-like RAW 264.7 cells. Fluorescent images of LVAN-encapsulating near-infrared (NIR) dye, S0456 (LVAN-S0456) clearly indicated that LVAN-S0456 had reduced renal excretion with very low fluorescent intensity in the kidneys. It is anticipated that the long circulation and reduced kidney clearance of LVAN-S0456 compared to VAN-S0456 injected in mice can lead to enhanced efficacy against MRSA infections with reduced nephrotoxicity. Overall, our developed formulations of VAN when administered alone or in combination with CFZ, provide a rational approach for combating MRSA infections.
Europium-Doped Sol-Gel SiO2-Based Glasses: Effect of the Europium Source and Content, Magnesium Addition and Thermal Treatment on Their Photoluminescence Properties
Authors: Fneich Hussein , Gaumer Nathalie , Chaussedent Stéphane , Blanc Wilfried , Mehdi Ahmad
Published: July 2018

Rare-earth doped silica-based glasses lead the optical materials due to their tailorable spectroscopic and optical properties. In this context, we took advantage of the sol-gel process to prepare various Eu-doped silica glasses to study their luminescent properties before and after annealing at 900 °C. The effect of magnesium on these properties was studied in comparison with Mg-free-glass. Using TEM, nitrogen sorption, XRD and FT-IR, we confirmed that the magnesium modifies the glass structure and the thermal treatment eliminates the aqueous environment, modifying the structure ordering. The emission spectra and the decay time curves show the advantages of the Mg addition and the annealing on the photoluminescent properties.
Tetrel Bonding Interactions in Perchlorinated Cyclopenta- and Cyclohexatetrelanes: A Combined DFT and CSD Study
Authors: Bauzá Antonio , Frontera Antonio
Published: July 2018

In this manuscript, we combined DFT calculations (PBE0-D3/def2-TZVP level of theory) and a Cambridge Structural Database (CSD) survey to evaluate the ability of perchlorinated cyclopenta- and cyclohexatetrelanes in establishing tetrel bonding interactions. For this purpose, we used Tr5Cl10 and Tr6Cl12 (Tr = Si and Ge) and HCN, HF, OH− and Cl− as electron donor entities. Furthermore, we performed an Atoms in Molecules (AIM) analysis to further describe and characterize the interactions studied herein. A survey of crystal structures in the CSD reveals that close contacts between Si and lone-pair-possessing atoms are quite common and oriented along the extension of the covalent bond formed by the silicon with the halogen atom.
Carapanosins D—F from the Seeds of Andiroba (Carapa guianensis, Meliaceae) and Their Effects on LPS-Activated NO Production
Authors: Inoue Takanobu , Ohmori Shoko , Kikuchi Takashi , Yamada Takeshi , Tanaka Reiko
Published: July 2018

A novel nor-phragmalin-type limonoid, named carapanosin D (1), and two novel mexicanolide-type limonoids, carapanosins E (2) and F (3), were isolated from the seed oil of andiroba (Carapa guianensis Aublet), a traditional medicine in Brazil and Latin American countries. Their structures were unambiguously determined on the basis of spectroscopic analyses using one-dimensional (1D) and two-dimensional (2D) NMR techniques and High resolution Fast Atom Bombardment Mass Spectrometry (HRFABMS). Compounds 1–3 were evaluated for their effects on the production of nitric oxide (NO) in Lipopolysaccharide (LPS)-activated mouse peritoneal macrophages. The NO inhibitory assay suggested that compounds 2 and 3 have high potency as inhibitors of macrophage activation.
One-Dimensional 13C NMR Is a Simple and Highly Quantitative Method for Enantiodiscrimination
Authors: Lankhorst Peter P. , Van Rijn Jozef H. J. , Duchateau Alexander L. L.
Published: July 2018

The discrimination of enantiomers of mandelonitrile by means of 1D 13C NMR and with the aid of the chiral solvating agent (S)-(+)-1-(9-anthryl)-2,2,2-trifluoroethanol (TFAE) is presented. 1H NMR fails for this specific compound because proton signals either overlap with the signals of the chiral solvating agent or do not show separation between the (S)-enantiomer and the (R)-enantiomer. The 13C NMR method is validated by preparing artificial mixtures of the (R)-enantiomer and the racemate, and it is shown that with only 4 mg of mandelonitrile a detection limit of the minor enantiomer of 0.5% is obtained, corresponding to an enantiomeric excess value of 99%. Furthermore, the method shows high linearity, and has a small relative standard deviation of only 0.3% for the minor enantiomer when the relative abundance of this enantiomer is 20%. Therefore, the 13C NMR method is highly suitable for quantitative enantiodiscrimination. It is discussed that 13C NMR is preferred over 1H NMR in many situations, not only in molecules with more than one chiral center, resulting in complex mixtures of many stereoisomers, but also in the case of molecules with overlapping multiplets in the 1H NMR spectrum, and in the case of molecules with many quaternary carbon atoms, and therefore less abundant protons.
Formation of a Family of Long Intergenic Noncoding RNA Genes with an Embedded Translocation Breakpoint Motif in Human Chromosomal Low Copy Repeats of 22q11.2—Some Surprises and Questions
Authors: Delihas Nicholas
Published: July 2018

A family of long intergenic noncoding RNA (lincRNA) genes, FAM230 is formed via gene sequence duplication, specifically in human chromosomal low copy repeats (LCR) or segmental duplications. This is the first group of lincRNA genes known to be formed by segmental duplications and is consistent with current views of evolution and the creation of new genes via DNA low copy repeats. It appears to be an efficient way to form multiple lincRNA genes. But as these genes are in a critical chromosomal region with respect to the incidence of abnormal translocations and resulting genetic abnormalities, the 22q11.2 region, and also carry a translocation breakpoint motif, several intriguing questions arise concerning the presence and function of the translocation breakpoint sequence in RNA genes situated in LCR22s.
Analytical Solutions of One-Dimensional Contaminant Transport in Soils with Source Production-Decay
Authors: Moranda Arianna , Cianci Roberto , Paladino Ombretta
Published: July 2018

An analytical solution in closed form of the advection-dispersion equation in one-dimensional contaminated soils is proposed in this paper. This is valid for non-conservative solutes with first order reaction, linear equilibrium sorption, and a time-dependent Robin boundary condition. The Robin boundary condition is expressed as a combined production-decay function representing a realistic description of the source release phenomena in time. The proposed model is particularly useful to describe sources as the contaminant release due to the failure in underground tanks or pipelines, Non Aqueous Phase Liquid pools, or radioactive decay series. The developed analytical model tends towards the known analytical solutions for particular values of the rate constants.
The PHD Transcription Factor Rum1 Regulates Morphogenesis and Aflatoxin Biosynthesis in Aspergillus flavus
Authors: Hu Yule , Yang Guang , Zhang Danping , Liu Yaju , Li Yu , Lin Guanglan , Guo Zhiqiang , Wang Shihua , Zhuang Zhenhong
Published: July 2018

Aspergillus flavus produces mycotoxins especially aflatoxin B1 and infects crops worldwide. As a PHD transcription factor, there is no report on the role of Rum1 in the virulence of Aspergillus spp. yet. This study explored the biological function of Rum1 in A. flavus through the construction of rum1 deletion mutants and rum1 complementation strains with the method of homologous recombination. It was found, in the study, that Rum1 negatively regulates conidiation through abaA and brlA, positively regulates sclerotia formation through nsdC, nsdD, and sclR, triggers aflatoxin biological synthesis, and enhances the activity of amylase. Our findings suggested that Rum1 plays a major role in the growth of mycelia, conidia, and sclerotia production along with aflatoxin biosynthesis in A. flavus.
Cosmological Constant from Condensation of Defect Excitations
Authors: Dittrich Bianca
Published: July 2018

A key challenge for many quantum gravity approaches is to construct states that describe smooth geometries on large scales. Here we define a family of (2+1)-dimensional quantum gravity states which arise from curvature excitations concentrated at point like defects and describe homogeneously curved geometries on large scales. These states represent therefore vacua for three-dimensional gravity with different values of the cosmological constant. They can be described by an anomaly-free first class constraint algebra quantized on one and the same Hilbert space for different values of the cosmological constant. A similar construction is possible in four dimensions, in this case the curvature is concentrated along string-like defects and the states are vacua of the Crane-Yetter model. We will sketch applications for quantum cosmology and condensed matter.
Preparation and X-ray structure of 2-iodoxybenzenesulfonic acid (IBS) – a powerful hypervalent iodine(V) oxidant
Authors: Mironova Irina A , Postnikov Pavel S , Yusubova Rosa Y , Yoshimura Akira , Wirth Thomas , Zhdankin Viktor V , Nemykin Victor N , Yusubov Mekhman S
Published: July 2018

The selective preparation of 2-iodoxybenzenesulfonic acid (IBS, as potassium or sodium salts) by oxidation of sodium 2-iodobenzenesulfonate with Oxone or sodium periodate in water is reported. The single crystal X-ray diffraction analysis reveals a complex polymeric structure consisting of three units of IBS as potassium salt and one unit of 2-iodoxybenzenesulfonic acid linked together by relatively strong I=O···I intermolecular interactions. Furthermore, a new method for the preparation of the reduced form of IBS, 2-iodosylbenzenesulfonic acid, by using periodic acid as an oxidant, has been developed. It has been demonstrated that the oxidation of free 2-iodobenzenesulfonic acid under acidic conditions affords an iodine(III) heterocycle (2-iodosylbenzenesulfonic acid), while the oxidation of sodium 2-iodobenzenesulfonate in neutral aqueous solution gives the iodine(V) products.
The NANOGrav 11 yr Data Set: Arecibo Observatory Polarimetry and Pulse Microcomponents
Authors: Gentile Peter A. , McLaughlin Maura A. , Demorest Paul B. , Stairs Ingrid H. , Arzoumanian Zaven , Crowter Kathryn , Dolch Timothy , DeCesar Megan E. , Ellis Justin A. , Ferdman Robert D. , Ferrara Elizabeth C. , Fonseca Emmanuel , Gonzalez Marjorie E. , Jones Glenn , Jones Megan L. , Lam Michael T. , Levin Lina , Lorimer Duncan R. , Lynch Ryan S. , Ng Cherry , Nice David J. , Pennucci Timothy T. , Ransom Scott M. , Ray Paul S. , Spiewak Renée , Stovall Kevin , Swiggum Joseph K. , Zhu Weiwei
Published: July 2018

We present the polarization pulse profiles for 28 pulsars observed with the Arecibo Observatory by the North American Nanohertz Observatory for Gravitational Waves timing project at 2.1 GHz, 1.4 GHz, and 430 MHz. These profiles represent some of the most sensitive polarimetric millisecond pulsar profiles to date, revealing the existence of microcomponents (that is, pulse components with peak intensities much lower than the total pulse peak intensity). Although microcomponents have been detected in some pulsars previously, we present microcomponents for PSR B1937+21, PSR J1713+0747, and PSR J2234+0944 for the first time. These microcomponents can have an impact on pulsar timing, geometry, and flux density determination. We present rotation measures for all 28 pulsars, determined independently at different observation frequencies and epochs, and find the Galactic magnetic fields derived from these rotation measures to be consistent with current models. These polarization profiles were made using measurement equation template matching, which allows us to generate the polarimetric response of the Arecibo Observatory on an epoch-by-epoch basis. We use this method to describe its time variability and find that the polarimetric responses of the Arecibo Observatory's 1.4 and 2.1 GHz receivers vary significantly with time.
Saturation Effect on Photoionization-driven Broad Absorption Line Variability
Authors: Lu 陆伟 Wei-Jian 坚 , Lin 林樱 Ying-Ru 如
Published: July 2018

We study the saturation effect on broad absorption line (BAL) variability through a variation phenomenon, which shows significant variation in Si iv BAL but no, or only small, change in C iv BAL (hereafter Phenomenon I). First, we explore a typical case showing Phenomenon I, quasar SDSS J153715.74+582933.9 (hereafter J1537+5829). We identify four narrow absorption line (NAL) systems within its Si iv BAL and two additional NAL systems within its C iv BAL, and confirm their coordinated weakening. Combining with the obvious strengthening of the ionizing continuum, we attribute the BAL variability in J1537+5829 to the ionization changes caused by the continuum variations. Second, a statistical study based on multiobserved quasars from SDSS-I/II/III are presented. We confirm that (1) the moderate anticorrelation between the fractional variations of Si iv BALs and the continuum in 74 quasars show Phenomenon I and (2) the sample showing BAL variations tends to have larger ionizing continuum variations. These results reveal the ubiquitous effect of the continuum variability on Phenomenon I and BAL variation. We attribute the relative lack of variation of C iv BALs in Phenomenon I to the saturation effects. Nonetheless, these absorbers are not very optically thick in Si iv and the ionization changes in response to continuum variations could be the main driver of their variations. Finally, we find that the saturation effect on BAL variability can explain many phenomena of BAL variations that have been reported before.
Galactic Planetary Nebulae as Probes of Radial Metallicity Gradients and Other Abundance Patterns
Authors: Stanghellini Letizia , Haywood Misha
Published: July 2018

We use planetary nebulae (PNe) as probes to determine the Galactic radial oxygen gradients and other abundance patterns. We select data homogeneously from recent data sets, including PNe at large Galactocentric distances. The radial oxygen gradient calculated for the general PN population, which probes the region from the Galactic center out to ∼28 kpc, is shallow, with slope ∼−0.02 dex kpc−1, in agreement with previous findings. We looked for time evolution of the metallicity gradient using PNe with different age progenitors as metallicity probes. We identify PNe whose progenitor stars are younger than 1 Gyr (YPPNe) and those whose progenitor stars are older than 7.5 Gyr (OPPNe) based on the comparison between evolutionary yields and elemental abundances of the PNe. By studying OPPNe and YPPNe separately, we found that (i) the OPPNe oxygen gradient is shallower (∼−0.015 dex kpc−1) than that derived from YPPNe (∼−0.027 dex kpc−1); (ii) the OPPNe inner radial distribution of oxygen is compatible with no gradient to the radial extent of the thick disk population (∼10 kpc), similarly to what has been observed in thick disk stars; and (iii) PNe (especially OPPNe) indicate that significant gradient slope is limited to Galactocentric distances between ∼10 and ∼13.5 kpc, as observed for open clusters and field stars. Outside this range, the distribution is almost flat. We found that the radial oxygen gradient is steeper for a PN population closer to the Galactic disk, similar to what is observed in the general stellar population by the SEGUE survey. We use our novel population dating to compare our results with current chemical evolutionary models and gradients from other Galactic populations for insight on galaxy chemical evolution.
Probing Cosmology with Dark Matter Halo Sparsity Using X-Ray Cluster Mass Measurements
Authors: Corasaniti P. S. , Ettori S. , Rasera Y. , Sereno M. , Amodeo S. , Breton M.-A. , Ghirardini V. , Eckert D.
Published: July 2018

We present a new cosmological probe for galaxy clusters, the halo sparsity. This characterizes halos in terms of the ratio of halo masses measured at two different radii and carries cosmological information encoded in the halo mass profile. Building on the work of Balmes et al., we test the properties of the sparsity using halo catalogs from a numerical N-body simulation of (2.6 Gpc h
−1)3 volume with 40963 particles. We show that at a given redshift the average sparsity can be predicted from prior knowledge of the halo mass function. This provides a quantitative framework to infer cosmological parameter constraints using measurements of the sparsity of galaxy clusters. We show this point by performing a likelihood analysis of synthetic data sets with no systematics, from which we recover the input fiducial cosmology. We also perform a preliminary analysis of potential systematic errors and provide an estimate of the impact of baryonic effects on sparsity measurements. We evaluate the sparsity for a sample of 104 clusters with hydrostatic masses from X-ray observations and derive constraints on the cosmic matter density Ω
m
and the normalization amplitude of density fluctuations at the 8 Mpc h
−1 scale, σ
8. Assuming no systematics, we find Ω
m
 = 0.42 ± 0.17 and σ
8 = 0.80 ± 0.31 at 1σ, corresponding to

. Future cluster surveys may provide opportunities for precise measurements of the sparsity. A sample of a few hundred clusters with mass estimate errors at the few percent level can provide competitive cosmological parameter constraints complementary to those inferred from other cosmic probes.
On the Variability of the Solar Mean Magnetic Field: Contributions from Various Magnetic Features on the Surface of the Sun
Authors: Bose Souvik , Nagaraju K.
Published: July 2018

The solar mean magnetic field (SMMF) is referred to as the disk-averaged line-of-sight (LOS) magnetic field that also reflects the polarity imbalance of the magnetic field on the Sun. The origin of the SMMF has been debated over the past few decades, with one school of thought suggesting that the contribution to the SMMF is mostly due to the large-scale magnetic field structure, also called the background magnetic field, whereas other and more recent studies have indicated that active regions have a major contribution to the observed SMMF. In this paper, we re-investigate the issue of the origin of the SMMF by decomposing the solar disk into plages, networks, sunspots, and background regions, thereby calculating the variation in the observed SMMF due to each of these features. We have used full-disk images from Solar Dynamics Observatory (SDO)/AIA recorded at 1600 Å for earmarking plages, networks, and background regions and 4500 Å images for separating the sunspots. The LOS fields corresponding to each of these regions are estimated from the co-temporal SDO/Helioseismic and Magnetic Imager full-disk magnetograms. The temporal variation of the SMMF shows a near one-to-one correspondence with that of the background field regions, suggesting that they constitute the major component of the observed SMMF. A linear regression analysis based on the coefficient of determination shows that the background field dominates and accounts for 89% of the variation in the SMMF, whereas the magnetic field from the other features accounts for the rest 11%.
Formation and Destruction of SiS in Space
Authors: Zanchet Alexandre , Roncero Octavio , Agúndez Marcelino , Cernicharo José
Published: July 2018

The presence of SiS in space seems to be restricted to a few selected types of astronomical environments. It is long known to be present in circumstellar envelopes around evolved stars and it has also been detected in a handful of star-forming regions with evidence of outflows, like Sgr B2, Orion KL, and more recently, L1157-B1. The kinetics of reactions involving SiS is very poorly known and here we revisit the chemistry of SiS in space by studying some potentially important reactions of the formation and destruction of this molecule. We calculated ab initio potential energy surfaces of the SiOS system and computed rate coefficients in the temperature range of 50–2500 K for the reaction of the destruction of SiS in collisions with atomic O, and of its formation, through the reaction between Si and SO. We find that both of the reactions are rapid, with rate coefficients of a few times 10−10 cm3 s−1, almost independent of temperature. In the reaction between Si and SO, SiO production is 5–7 times more efficient than SiS formation. The reaction of SiS with O atoms can play an important role in destroying SiS in envelopes around evolved stars. We built a simple chemical model of a postshock gas to study the chemistry of SiS in protostellar outflows and we found that SiS forms with a lower abundance and later than SiO, that SiS is efficiently destroyed through reaction with O, and that the main SiS-forming reactions are Si + SO and Si + SO2.
Mysterious meiotic behavior of autopolyploid and allopolyploid maize
Authors: Iqbal Muhammad Zafar , MingJun Cheng , Zhao Yanli , Wen Xiaodong , Zhang Ping , Zhang Lei , Ali Asif , Rong Tingzhao , Tang Qi Lin
Published: July 2018

This study was aimed to investigate the stability of chromosomes during meiosis in autopolyploid and allopolyploid maize, as well as to determine an association of chromosomes between maize (Zeamaysssp.mays Linnaeus, 1753) andZ.perennis(Hitchcock, 1922) Reeves & Mangelsdor, 1942, by producing a series of autopolyploid and allopolyploid maize hybrids. The intra-genomic and inter-genomic meiotic pairings in these polyploids were quantified and compared using dual-color genomic in-situ hybridization. The results demonstrated higher level of chromosome stability in allopolyploid maize during meiosis as compared to autopolyploid maize. In addition, the meiotic behavior ofZ.perenniswas relatively more stable as compared to the allopolyploid maize. Moreover, ten chromosomes of "A” subgenome in maize were homologous to twenty chromosomes ofZ.perennisgenome with a higher pairing frequency and little evolutionary differentiation. At the same time, little evolutionary differentiation has been shown by chromosomes of "A” subgenome in maize, while chromosomes of "B” subgenome, had a lower pairing frequency and higher evolutionary differentiation. Furthermore, 5IM+ 5IIPP+ 5IIIMPPand 5IIMM+ 5IIPP+ 5IVMMPPwere observed in allotriploids and allotetraploids respectively, whereas homoeologous chromosomes were found between the "A” and "B” genome of maize andZ.perennis.
Wireless communications beyond 5G: Uncertainties of terahertz wave attenuation due to rain
Authors: Tamošiūnaitė Milda , Tamošiūnas Vincas , Valušis Gintaras
Published: July 2018

Statistical peculiarities of terahertz (THz) wave attenuation in heavy rain conditions are evaluated. The expected extreme densification of the infrastructure and the application of highly directional beams of 5th generation (5G) and beyond 5G (B5G) wireless networks were taken into account. Calculations were performed emulating both drop size distributions of the real rain and the laboratory-controlled rain described in literature. Simulation results revealed that absorbance fluctuations of more than one percent would occur if THz waves and raindrops interact within the 100 m3volume. For much smaller volumes, short distances and narrow beams used for experiments with the laboratory-controlled rain, absorbance uncertainties could exceed the average absorbance value. A comparison of the simulation results at fixed average absorbance revealed that slightly lower uncertainties were expected in the case of a single raindrop size when compared to the Weibull distribution approximating the real rain. Nevertheless, in both cases the predicted deviations were substantially smaller than observed in the previously published experimental results. This fact predicts a new future application possibility for such laboratory-based experiments – they can be employed to predict the performance of wireless THz data transmission links when the resilience margin is required. Since much of the existing industrial test equipment is not designed to carry out calibrated over-the-air measurements of 5G/B5G wireless networks, such experiments can be employed to primarily predict the performance of data transmission links.
Human Extrafollicular CD4+ Th Cells Help Memory B Cells Produce Igs
Authors: Kim Sang Taek , Choi Jin-Young , Lainez Begona , Schulz Vincent P. , Karas David E. , Baum Eric D. , Setlur Jennifer , Gallagher Patrick G. , Craft Joe
Published: July 2018

Follicular helper T (Tfh) cells are necessary for germinal center B cell maturation during primary immune responses; however, the T cells that promote humoral recall responses via memory B cells are less well defined. In this article, we characterize a human tonsillar CD4+ T cell subset with this function. These cells are similar to Tfh cells in terms of expression of the chemokine receptor CXCR5 and the inhibitory receptor PD-1, IL-21 secretion, and expression of the transcription factor BCL6; however, unlike Tfh cells that are located within the B cell follicle and germinal center, they reside at the border of the T cell zone and the B cell follicle in proximity to memory B cells, a position dictated by their unique chemokine receptor expression. They promote memory B cells to produce Abs via CD40L, IL-10, and IL-21. Our results reveal a unique extrafollicular CD4+ T cell subset in human tonsils, which specialize in promoting T cell–dependent humoral recall responses.
$K$-differenced vector random fields
Authors: Alsultan Rehab , Ma Chunsheng
Published: July 2018

A thin-tailed vector random field, referred to as a $K$-differenced vector random field, is introduced.
Its finite-dimensional densities are the differences of two Bessel functions of second order, whenever
they exist, and its finite-dimensional characteristic functions have simple closed forms as the
differences of two power functions or logarithm functions. Its finite-dimensional distributions have thin
tails, even thinner than those of a Gaussian one, and it reduces to a Linnik or Laplace vector random
field in a limiting case. As one of its most valuable properties, a $K$-differenced vector random field is
characterized by its mean and covariance matrix functions just like a Gaussian one. Some covariance
matrix structures are constructed in this paper for not only the $K$-differenced vector random field, but
also for other second-order elliptically contoured vector random fields. Properties of the multivariate
$K$-differenced distribution are also studied.
Exact bounds on the truncated-tilted mean, with applications
Authors: Pinelis Iosif F
Published: July 2018

Получены точные верхние оценки для ${\mathbf{E} Xe^{h(X\wedge w)}}/{\mathbf{E} e^{h(X\wedge w)}}$ - математического ожидания преобразования Крамера так называемого винзоризованного распределения случайной величины $X$ - в терминах первых двух моментов. Такие результаты необходимы для работы над неравномерными оценками типа Берри-Эссеена для общих нелинейных статистик. В качестве другого приложения предложены оптимальные верхние оценки байесовского апостериорного среднего.
Также представлены некоторые свойства монотонности упомянутого математического ожидания преобразования Крамера.
Оценки с асимптотически равномерно минимальным $d$-риском
Authors: Zaikin Artem Aleksandrovich
Published: July 2018

В рамках общей теории статистического вывода вводится определение решающей функции с асимптотически ($n\to\infty$) равномерно минимальным $d$-риском. Представленное определение применяется к доказательству того, что оценка максимального правдоподобия скалярного параметра является оценкой с асимптотически равномерно минимальным $d$-риском (распространение результата Володина-Новикова [1] для сжимающихся априорных распределений на общий класс непрерывных распределений). При доказательстве используется асимптотическое представление функции апостериорного риска, полученное в статье [2].
La arqueología virtual: de la excavación arqueológica a la gestión y socialización del patrimonio. Les cases de la Catedral (Tortosa) y el yacimiento protohistórico de La Cella(Salou), Tarragona
Authors: Cots Ivan , Vilà Jordi , Diloli Jordi , Ferré Ramon , Bricio Laura
Published: July 2018

This article reports how the new information technologies are used in two practical examples in the field of archaeology from the early stages of excavation up to the reporting of the results. The first example is an urban settlement focused on the process of documentation and recording, the presentation of the archaeological remains and the resulting museum discourse in Tortosa, Tarragona (Spain). The second example is a settlement near the coast with no urban problems or conditions, which is more focused on the diffusion of research results through a variety of virtual communication channels (La Cella, Salou). In this regard, we present a variety of techniques and systems that we apply to achieve our objectives. Photogrammetry is now an essential tool for recording archaeological data because it facilitates fieldwork, provides extremely accurate measurements and considerably increases the quality of the result. It also enables archaeological and heritage research to be socialized and the results target scientific and interpretative analysis. If it is combined with the appropriate software, the remains of artefacts and buildings recovered at the sites, and which in some cases cannot be conserved, can be displayed in 3D. Finally, it can be used to make recreations and virtual interpretations that can present all these archaeological data to a non-specialized public in the form of a virtual museum, an immersive virtual reality experience, or can be applied to improve scientific research, through 3D modelling and virtual experimentation.

Highlights:

Photogrammetric technique saves the real information that emerges and prevents much of it from disappearing, a common occurrence in archaeological excavations.

Virtual reconstruction is an effective method of presenting the results in an educational way for the general public.

The final product needs to show the result of a scientific hypothesis in an attractive and understandable way.
ScientificWorkflows Applied to the Coupling of a Continuum
(Elmer v8.3) and a Discrete Element (HiDEM v1.0) Ice Dynamic
Model
Authors: Memon Shahbaz , Vallot Dorothée , Zwinger Thomas , Åström Jan , Neukirchen Helmut , Riedel Morris , Book Matthias
Published: July 2018

Abstract. Scientific computing applications involving complex simulations and data-intensive processing are often composed of multiple tasks forming a workflow of computing jobs. Scientific communities running such applications on distributed and heterogeneous computing resources find it cumbersome to manage and monitor the execution of these tasks. Scientific workflow management systems (WMS) can be used to automate and simplify complex task structures by providing tooling for the composition and execution of workflows across distributed and heterogeneous computing environments. As a case study, we apply the UNICORE workflow management system to a formerly hard-coded coupling of a glacier sliding and calving simulation that contains many tasks and dependencies, ranging from pre-processing and data management to repetitive executions in heterogeneous high-performance computing (HPC) resource environments. Using the UNICORE workflow management system, the composition, management, and execution of the glacier modelling workflow becomes easier with respect to usage, monitoring, maintenance, re-usability, portability, and reproducibility in different environments and by different user groups.
Functional motivations behind direct object fronting in written Swedish: A corpus-distributional account
Authors: Hörberg Thomas
Published: July 2018

In Swedish, grammatical functions are primarily encoded by word order. In prototypical transitive sentences, the subject precedes the direct object. However, Swedish also allows for fronting of the direct object, although such sentences are potentially ambiguous with respect to grammatical functions. This study therefore investigates direct object fronting in written Swedish with respect to 1) which functions this construction serves and 2) whether the use of direct object fronting is dispreferred when the grammatical functions cannot be determined on other information types. These questions are investigated on the basis of quantitative differences in the distribution of NP prominence properties (e.g., givenness and animacy) and formal, morphosyntactic cues to grammatical functions (e.g., case marking and verb particles) between OVS and SVO sentences, and between OVS sentences and passives. The results indicate that direct object fronting is used when the object either is topical and highly discourse prominent, or when it is contrastive. I also argue that direct object fronting is used to introduce new topics into the discourse. Subjects are more frequently high in discourse prominence in object-initial sentences than in subject-initial sentences. I suggest that this stems from a motivation to keep the information in object-initial sentences following the sentence-initial object “informationally light” and predictable. Unambiguous formal markers of grammatical functions are used more frequently in OVS sentences than in SVO sentences, but less frequently in passives than in SVO sentences. OVS sentences also more frequently contain an animate subject and an inanimate object than SVO sentences, and in passives, animate subjects and inanimate objects are even less frequent. Writers therefore seem to prefer the structurally unambiguous passive construction over the potentially ambiguous object-initial construction, when grammatical functions cannot be determined on the basis of other formal markers or an NP argument animacy difference. Further, sentences with two animate arguments more frequently contain formal markers than sentences with at most one animate argument. These findings indicate that writers actively avoid direct object fronting when it potentially results in an ambiguity, and provide evidence for the hypothesis that writers are inclined to actively avoid ambiguities more generally.
Sharing the gains in forest management: Insights from the application of principles of collective action
Authors: Alló Maria , Loureiro Maria L.
Published: July 2018

Aim of study: To analyze the factors that motivate the sharing of a contribution to a common pool resource (CPR).Area of study: We obtained data from Galicia communal forests during 2013-2014. Material and methods: A survey among forest owners in which questions about decisions, mimicking those in public good games, were included. In addition, the compliance with the principles of collective action (PCA), and their implications in the management of CPR were tested.Main results: PCA are not functioning perfectly in our sample of communal forest owners. In line with previous literature, results suggest that individuals are willing to share an important amount of endowment in a CPR. Examining the role that PCA play in individuals’ decisions, it was observable that when owners face the sharing of an endowment, the monitoring, conflict resolution mechanism and minimal recognition of rights imply more cooperative results. Current communal forests should promote a better application of these PCA in order to obtain a more cooperative behavior from their members.Research highlights: Communal forest owners are quite generous according to the results obtained. In addition, it has also been found that the endowment is an important factor to consider, while social aspects represented through the PCA also matter when explaining sharing decisions. The present study may be useful in order to promote stronger cooperation in local communities.
South African Invasive Tree: Studies of the Chemical and Biological Profiles of Acacia Decurrens (Wild)
Authors: Okoli B. , Jummai A. , Molefe N , Ledwaba I , Modis S.
Published: July 2018

In this study, we aimed to profile the stem bark of Acacia decurrens biochemically. Extracts obtained by maceration were phytochemically screened, spectroscopically analysed with the aid of UV-visible, FT-IR, GC-MS, and, ICP-OES and subjected to primary biological assay. Spectra obtained from the UV-visible and FT-IR confirm the presence of n ® p*  which are characteristic of compounds with oxygenated backbones such as the glycoside, phenols, terpenoids, tannins, and flavonoids. On further analysis, the chromatogram revealed the presence of thirty-five major compounds of which eight bioactive compounds had previously been isolated. The metal profile of the stem bark registered high concentrations of Cr, K, and Fe. Quantitative phytochemical evaluation showed, large amount of tannins (30.87 – 55. 81 mgTAE/g), steroids (13.92-41.2%), and phenols (40.6 - 65.5 mgGAE/g) in all fractions. The ethyl acetate and methanol fractions were found to be rich sources of antibacterial compounds with MIC value of 12.5 μg/mL while the chloroform fraction is a potent antioxidant fraction with IC50 values of 37.00 ± 0.06 g/mL and 42.20 ± 0.72 µg/mL against DPPH and ABTS radicals, respectively. The presence of these secondary metabolites and the hyper-tolerance capacity for metals can be exploited pharmaceutically and for phytoremediation purpose, respectively.
Drama in Education for Sustainable Development: Preservice Preschool Teachers on Stage
Authors: Akyol Tugce , Kahriman-Pamuk Deniz , Elmas Ridvan
Published: July 2018

Early childhood education for sustainable development roots on environmental, socio-cultural and economic ground for encouraging lifelong learning and improving values and behaviors that support sustainable development such as use of natural resources, cultural awareness, gender equality, and democracy. Educational drama contributes to the development of skills necessary for sustainable development such as communication, cooperation and decision-making. This study has two main objectives: the former is to raise awareness and to develop these skills of pre-service teachers by organizing drama activities in Education for Sustainable Development (ESD); the later objective is to implement and to evaluate the activities based on the data collected from pre-service teachers and from one specific pre-school teacher, in whose classroom these activities were carried out. Phenomenographic approach was adapted for the current study and the data was collected through interviews, photos, and field notes. The study shows that the drama activities increase awareness and improve skills for ESD within pre-service teachers. Furthermore, opinions and experiences of the pre-service teachers and the preschool teacher state that drama has positive impact on learning of pre-school children about sustainable development.
The Effect of Basic Position Training on Walking Abilities of Visually Impaired Individuals
Authors: Suveren-Erdogan Ceren , Er Fatmanur , Suveren Sibel
Published: July 2018

Objective of this study is to help the basic standing position training to take its part among basic exercises of the visually impaired individuals, and to observe the effects of this training on walking and balance skills.Method: 8 visually impaired sedentary individuals with impairment levels of B1 and B2 and ages of 18 to 24 voluntarily participated in the study. After acknowledging the visually impaired individuals with audial information regarding the study, they were told to brisk walk for 15 steps against the audio signal and then to heel-to-toe walk for 15 steps. Their corresponding walking distances, walking durations, directional impairments and losses of balance were recorded. During the 8 week period following this test, 45 minute training sessions accompanied by trainers that included 4 basic standing positions and their combinations were applied once a week, where the trainer corrected the individuals verbally and physically. Abovementioned tests were repeated after these 8 weeks. Gender categorization was not made since the participants were few in number. Non-parametric Wilcoxon Signed Rank Test was applied and a significant increase for the pretest was observed at a 0.05 significance level, where the distances walked increased and walking durations along with losses of balance decreased.Result: It was observed that walking skills of visually impaired individuals that received verbal and physical assistance, and that effectively performed basic positions and their combinations were smoother and more confident; that their walking distances were increased, their losses of balance were decreased and that they encountered less deviations from the direction of movement while walking, compared to their pretest conditions. Starting from this point of view, it might be concluded that the basic standing positions were highly beneficial and applicable activities for walking training of visually impaired individuals.
Optical and Photoacoustic Properties of Colloidal Silver Nanoparticles Solutions
Authors: Aldosari F. , M. Azzeer A. , M. Hassib A.
Published: July 2018

The study has aimed to investigate optical and photoacoustic properties of some colloidal silver nanoparticles at different concentration over the time. The phase purity with crystal structure of silver nanoparticles were studied using X-ray diffraction (XRD) and was confirmed by Transmission Electron Microscopy (TEM). Optical property was changed during the variable concentration of nanoparticles and duration time of sample. The absorbance of silver colloidal solutions is increased, when concentration increases but decreased with respective to the longer period of sample. Absorption peaks and stability of particles in solutions is influenced by the duration time of solution and its concentration. The low concentration-based solutions fall in the absorbance over the times. The observed PA signal is subjected by the factor of parameters; such as, pump wavelengths, energy, repetition rate, concentrations, and temperature. Stability of fluorescence and absorption peaks are influenced by the concentration of particles and time period of colloidal solution. Effects on PA signal with fluorescent and absorption peaks upon the concentration was also significant.
Clinical Utility of the Combined Positive Score for Programmed Death Ligand-1 Expression and the Approval of Pembrolizumab for Treatment of Gastric Cancer
Authors: Kulangara Karina , Zhang Nancy , Corigliano Ellie , Guerrero Lindsay , Waldroup Stephanie , Jaiswal Dipeshkumar , MS Malinka Jansson , Shah Supriya , Hanks Debra , Wang Jiangdian , Lunceford Jared , Savage Mary J. , Juco Jonathan , Emancipator Kenneth
Published: July 2018

Context.—

Regulatory approval of pembrolizumab for treatment of gastric and gastroesophageal junction (G/GEJ) adenocarcinoma required a reproducible scoring method for use of programmed death ligand-1 (PD-L1) protein expression as a companion diagnostic to identify likely responders to therapy.

Objective.—

To develop an immunohistochemical scoring algorithm that includes PD-L1 expression for tumor and immune cells, that is, the combined positive score.

Design.—

Four previously treated tumor types in the KEYNOTE-012 and KEYNOTE-028 studies were analyzed descriptively with a version of the PD-L1 immunohistochemical 22C3 pharmDx assay labeled for investigational use only to determine the relative importance of PD-L1 expression in tumor versus immune cells as a biomarker for pembrolizumab response. A combined positive score was developed as a novel scoring method and was compared with the tumor proportion score in cohort 1 from the KEYNOTE-059 study (G/GEJ cancer). External reproducibility was assessed.

Results.—

Per combined positive score cutoff of 1 or more, the prevalence of PD-L1 expression in patients with G/GEJ cancer was 57.6% (148 of 257 patients), with reasonable enrichment of responses (odds ratio, 2.8). Per tumor proportion score cutoff of 1% or more, prevalence was 12.5% (32 of 257 patients), with minimal enrichment (odds ratio, 1.4). External reproducibility assessments demonstrated interpathologist overall agreement of 96.6% (591 of 612; 95% CI, 94.0%–98.7%) and intrapathologist overall agreement of 97.2% (595 of 612; 95% CI, 95.3%–98.9%).

Conclusions.—

Combined positive score is a robust, reproducible PD-L1 scoring method that predicts response to pembrolizumab in patients with G/GEJ cancer. This novel scoring method supported US Food and Drug Administration approval of pembrolizumab as third-line therapy for G/GEJ cancer and has facilitated investigation in other indications.