bluuebunny/crossref_metadata_2025 huggingface dataset:
High-performance poly(lactide) composites by construction of network-like shish-kebab crystals
Authors: Shen Tianfeng , Xu Yunsheng , Ma Piming , Wang Likui , Dong Weifu , Chen Mingqing
Published: July 2016

Novel high-performance PLA composites were prepared by solid-state uniaxial stretching with the OXA as needle-like nucleation templates leading to a unique network-like shish-kebab crystal structures with a tensile strength above 120 MPa.
Novel fluorine-free 2,2′-bis(4,5-dimethylimidazole) additive for lithium-ion poly(methyl methacrylate) solid polymer electrolytes
Authors: Romero Mariano , Faccio Ricardo , Mombrú Álvaro W.
Published: July 2016

In this report, we study the effect of the addition of fluorine-free 2,2′-bis(4,5-dimethylimidazole) (BDI) on lithium-ion solid polymer electrolytes based on lithium nitrate and poly(methyl methacrylate) (PMMA).
Base-driven keto–enol anion tautomerism of a perylene diimide derivative in DMF solution
Authors: Wang Jianmin , He Enfang , Wang Hailong , Hou Wenlong , Xu Jing , Guo Huiyun , Wang Xiao , Zhang Zhenlin , Zhang Ruijun , Zhang Haiquan
Published: July 2016

A perylene diimide derivative (d-THBPDI) containing twisted heptatomic biphenyl substituents in the bay positions exhibited base (hydrazine, 1,2-ethylenediamine, triethylamine and K2CO3)-driven keto–enol anion tautomerism in DMF solution.
Bottom-up direct writing approach for controlled fabrication of WS2/MoS2 heterostructure systems
Authors: Dong Rui , Moore Logan , Aripova Nozima , Williamson Christopher , Schurz Robert , Liu Yuzi , Ocola Leonidas E. , Kuljanishvili Irma
Published: July 2016

We demonstrate a scalable production of quality WS2/MoS2 vertical and lateral heterostructures with controlled geometries employing a bottom-up direct writing approach.
Structure- and solvent-triggered influences in the self-assembly of polyoxometalate–steroid conjugates
Authors: Yang Hai-Kuan
Published: July 2016

The supramolecular structures formed by polyoxometalate–steroid conjugates can be greatly influenced by molecular structures and solution components.
Enhanced oxidative and adsorptive capability towards antimony by copper-doping into magnetite magnetic particles
Authors: Qi Zenglu , Lan Huachun , Joshi Tista Prasai , Liu Ruiping , Liu Huijuan , Qu Jiuhui
Published: July 2016

Copper-doped magnetite improved particle size, enhanced adsorption capacity of antimony (Sb) and oxidation ability of Sb (III).
A facile, fast responsive and highly selective mercury(ii) probe characterized by the fluorescence quenching of 2,9-dimethyl-1,10-phenanthroline and two new metal–organic frameworks
Authors: Shan Fa-Shuo , Lai Jia-Ping , Sun Hui , Zhang Ping , Luo Chong , He Yan-Hui , Feng Huan-Ran
Published: July 2016

A fast responsive and highly selective mercury(ii) sensor was developed using the fluorescence quenching mechanism of 2,9-dimethyl-1,10-phenanthroline (2,9-DMP) towards mercury(ii).
Mesoporous NiCo2O4 nanospheres with a high specific surface area as electrode materials for high-performance supercapacitors
Authors: Pang M. J. , Jiang S. , Long G. H. , Ji Y. , Han W. , Wang B. , Liu X. L. , Xi Y. L. , Xu F. Z. , Wei G. D.
Published: July 2016

Ternary nickel cobaltite has attracted more and more attention as a promising electrode material for high performance supercapacitors (SCs) due to its high theoretical capacity, unique crystal structure and excellent electronic conductivity.
The effect of fluorination on the surface structure of truxenones
Authors: Rochford L. A. , Ramadan A. J. , Holliday S. , Jones T. S. , Nielsen C. B.
Published: July 2016

The surface structure of partially fluorinated truxenone (F3-truxenone) molecules on Cu (111) has been probed using a combination of scanning tunneling microscopy (STM) and low energy electron diffraction (LEED).
Exterior and small carbide particle promoted platinum electrocatalyst for efficient methanol oxidation
Authors: Yan Zaoxue , Gao Lina , Zhao Xinhong , Wei Wei , Xie Jimin , Shen Pei Kang , Zhu Fen
Published: July 2016

Carbides have a synergistic effect on noble metal based electrocatalysts.
Synergism of metabolic modulators Bet-CA and LDCA: a rational combinatorial approach to selectively combat cancer associated hallmark traits
Authors: Ghosh Monisankar , Saha Suchandrima , Dutta Samir Kumar
Published: July 2016

The strategic combination of two metabolic modulators, Bet-CA and LDCA in a calculated ratio selectively and synergistically inhibits the hallmark traits of cancer by altering the highly resilient mitochondrial bioenergetics.
A new mechanism for allylic alcohol isomerization involving ruthenium nanoparticles as a ‘true catalyst’ generated through the self-assembly of supramolecular triruthenium clusters
Authors: Hitrik Maria , Dandapat Anirban , Sasson Yoel
Published: July 2016

A new five step mechanism has been established for allylic alcohol isomerization involving ruthenium nanoparticles as the ‘true catalyst’.
Remarkable substitution influence on the mechanochromism of cyanostilbene derivatives
Authors: Zhao He , Wang Yongtao , Harrington Steven , Ma Lei , Hu Shuzhi , Wu Xue , Tang Huan , Xue Mei , Wang Yubin
Published: July 2016

Well-designed full-color emission, AIE, CIEE-active luminogens and high contrast mechanochromic behaviour.
DFT study on 1,7-octadiene polymerization catalyzed by a non-bridged half-titanocene system
Authors: Pan Yu , Xu Xiaowei , Wei Ning-Ning , Hao Ce , Zhu Xiaodong , He Gaohong
Published: July 2016

For (η5-C5Me5)TiCl2(O-2,6-iPr2C6H3)/MAO system, the selectivity of repeated insertion and intramolecular cyclization of 1,7-octadiene were explored in detail by DFT method.
Amphiphilic drug–drug assembly via dual-responsive linkages for small-molecule anticancer drug delivery
Authors: Zhong Tian , Huang Ran , Tan Lianjiang
Published: July 2016

Amphiphilic drug–drug assembly nanoparticles based on dual-responsive H-bonding-instructed disulfide bonds can release irinotecan and doxorubicin simultaneously in cancer cells for anticancer purposes.
Zinc oxide as a hole blocking layer for perovskite solar cells deposited in atmospheric conditions
Authors: Hadouchi Warda , Rousset Jean , Tondelier Denis , Geffroy Bernard , Bonnassieux Yvan
Published: July 2016

A sputtered ZnO thin film was used as electron extraction layer, in a planar perovskite based solar cell. As a result a maximum power conversion efficiency (PCE) of 14.2%, measured at reverse scan, has been demonstrated.
Dual n-type units including pyridine and diphenylphosphine oxide: effective design strategy of host materials for high-performance organic light-emitting diodes
Authors: Li Wei , Li Jiuyan , Liu Di , Li Deli , Zhang Dan
Published: July 2016

The direct linking of dual n-type units is developed to design novel host materials for improved performance of blue and green phosphorescent organic light-emitting diodes.
Stretchable supramolecular hydrogels with triple shape memory effect
Authors: Le Xiaoxia , Lu Wei , Zheng Jing , Tong Dingyi , Zhao Ning , Ma Chunxin , Xiao He , Zhang Jiawei , Huang Youju , Chen Tao
Published: July 2016

Here, we present a novel mechanical stretchable supramolecular hydrogel with a triple shape memory effect at the macro/micro scale.
Sequence-defined oligo(ortho-arylene) foldamers derived from the benzannulation of ortho(arylene ethynylene)s
Authors: Lehnherr Dan , Chen Chen , Pedramrazi Zahra , DeBlase Catherine R. , Alzola Joaquin M. , Keresztes Ivan , Lobkovsky Emil B. , Crommie Michael F. , Dichtel William R.
Published: July 2016

A Cu-catalyzed benzannulation reaction transforms ortho(arylene ethynylene) oligomers into ortho-arylenes.
Room-temperature processed, air-stable and highly efficient graphene/silicon solar cells with an organic interlayer
Authors: Xu Dikai , Yu Xuegong , Gao Dace , Mu Xinhui , Zhong Mengyao , Yuan Shuai , Xie Jiangsheng , Ye Wenying , Huang Jiabin , Yang Deren
Published: July 2016

High-performance graphene/silicon (Gr/Si) solar cells are reported with four-month-stable efficiency over 11%.
Environmentally friendly reduced graphene oxide as a broad-spectrum adsorbent for anionic and cationic dyes via π–π interactions
Authors: Xiao Jianliang , Lv Weiyang , Xie Zhou , Tan Yeqiang , Song Yihu , Zheng Qiang
Published: July 2016

l-Cysteine reduced graphene oxide exhibits high adsorption capability towards anionic indigo carmine and cationic neutral red via π–π interactions.
Oxidative stress and inflammatory responses involved in dietary nickel chloride (NiCl2)-induced pulmonary toxicity in broiler chickens
Authors: Deng Jie , Guo Hongrui , Cui Hengmin , Fang Jing , Zuo Zhicai , Deng Junliang , Wang Xun , Zhao Ling
Published: July 2016

NiCl2intake induced the pulmonary oxidative stress and inflammatory responsesviadietary pathway, which subsequently contributed to histopathological lesions and dysfunction.
Sex and gender differences in HIV-1 infection
Authors: Griesbeck Morgane , Scully Eileen , Altfeld Marcus
Published: July 2016

The major burden of the human immunodeficiency (HIV) type 1 pandemic is nowadays carried by women from sub-Saharan Africa. Differences in the manifestations of HIV-1 infection between women and men have been long reported, and might be due to both socio-economic (gender) and biological (sex) factors. Several studies have shown that women are more susceptible to HIV-1 acquisition than men. Following HIV-1 infection, women have lower viral loads during acute infection and exhibit stronger antiviral responses than men, which may contribute to differences in the size of viral reservoirs. Oestrogen receptor signalling could represent an important mediator of sex differences in HIV-1 reservoir size and may represent a potential therapeutic target. Furthermore, immune activation, a hallmark of HIV-1 infection, is generally higher in women than in men and could be a central mechanism in the sex difference observed in the speed of HIV-1 disease progression. Here, we review the literature regarding sex-based differences in HIV-1 infection and discuss how a better understanding of the underlying mechanisms could improve preventive and therapeutic strategies.
Validating the Use of
D
for Measuring Lexical Diversity in Low-Income Kindergarten Children
Authors: Lai Stephanie A. , Schwanenflugel Paula J.
Published: July 2016

Purpose

Children from low–socioeconomic status families often perform poorly on standardized vocabulary assessments. The primary purpose of the study was to determine whether lexical diversity as measured by
D
(Malvern, Richards, Chipere, & Durán, 2004) serves as a valid measure of vocabulary in at-risk, low-income, predominantly African American kindergartners.

Method

Kane's (1992) argument-based approach was used to validate
D.
Six assumptions were examined. Kindergartners (
N
= 210) from a high-poverty, low-achievement region of the United States were recorded narrating a wordless picture book and assessed using the Expressive Vocabulary Test, Second Edition (Williams, 2007), and the Kaufman Test of Educational Achievement, Second Edition–Listening Comprehension subtest (Kaufman & Kaufman, 2004).

Results

D
was distributed normally and did not vary as a function of language sample length or child ethnicity.
D
was significantly but weakly related to the Expressive Vocabulary Test, Second Edition, indicating some distinction between
D
and the Expressive Vocabulary Test, Second Edition, scores. Further,
D
was only marginally related to the Kaufman Test of Educational Achievement, Second Edition–Listening Comprehension subtest.

Conclusions

Although evidence was somewhat mixed, the study supported the view that
D
is a potentially valid measure of lexical diversity among low-income, predominantly African American kindergartners and could be a useful supplement to standardized vocabulary measures.
Theoretical Principles to Guide the Teaching of Adjectives to Children Who Struggle With Word Learning: Synthesis of Experimental and Naturalistic Research With Principles of Learning Theory
Authors: Ricks Samantha L. , Alt Mary
Published: July 2016

Purpose

The purpose of this tutorial is to provide clinicians with a theoretically motivated and evidence-based approach to teaching adjectives to children who struggle with word learning.

Method

Given that there are almost no treatment studies to guide this topic, we have synthesized findings from experimental and theoretical literature to come up with a principles-based approach to treatment.

Results

We provide a sample lesson plan, incorporating our 3 theoretical principles, and describe the materials chosen and methods used during treatment and assessment.

Conclusion

This approach is theoretically motivated, but it needs to be empirically tested.
Wideband bandstop filter using hybrid microstrip/CPW‐DGS with via‐hole connection
Authors: Chen Hui , Jiang Di , Chen Xu
Published: July 2016

A novel wideband bandstop filter (BSF) with a minimum attenuation better than 28.5 dB and three transmission zeros within the stopband is proposed. The designed filter is composed of a top microstrip transmission line and a bottom coplanar waveguide open‐circuited resonator loaded by a periodical L‐shaped defected ground structure resonant unit cell. The top and bottom dual‐metal‐plane conductors are connected by the periodically metallic via‐hole within the designed substrate. With the appropriate height of substrate and separation between the adjacent metallic via‐holes, an excellent parallel‐plate‐metal synthesised transmission line with an improved coupling between the top and bottom resonators can be achieved by this via‐hole‐loaded technology. Finally, a microstrip BSF centred at 5.44 GHz with a measured 20 dB rejection bandwidth of more than 35.5% are designed, fabricated, and measured for this topology of validation.
Person re‐identification by graph‐based metric fusion
Authors: Xie Yi , Levine Martin D. , Yu Huimin
Published: July 2016

Person re‐identification is defined as re‐identifying individuals across different camera views. This is a very challenging problem since the appearance of a person can vary significantly due to cross‐camera changes in viewpoint, pose and illumination. To model the transition between camera views, distance metric learning has been widely used in person re‐identification and shown to be effective. However, using one specific metric often suffers from over‐fitting and may not be sufficient enough to cope with the cross‐camera variations of all different individuals. In this Letter, a powerful metric fusion method is proposed to combine multiple given distance metrics. Specifically, we represent given metrics as different graphs and then formulate the fusion problem as a graph‐based learning framework. In this way, our framework can efficiently integrate the complementary information provided by different input metrics.
Experimental validation of a hybrid converter with enhanced switching ripple cancellation
Authors: Papadopoulos Savvas , Klumpner Christian , Rashed Mohamed , Wheeler Patrick
Published: July 2016

This study presents the experimental evaluation of a proposed new three phase hybrid converter topology for medium voltage applications. The topology is based on the interconnection of a low switching frequency voltage source inverter (VSI), rated at medium voltage, with a high switching frequency low‐power rated current source inverter (CSI). The main function of the shunt connected CSI is to cancel the large switching current ripple produced by the VSI while operating at a reduced fundamental voltage enabled by the use of series connected capacitors. The simulations and design procedure outline the possibility of achieving high output grid current quality whilst the added installed power by the CSI remains at <4% compared with the VSI. The experimental results show good correlation between analytical/simulated targets of 20% maximum CSI voltage stress albeit with added installed power of 6.7% due to a larger amount of current ripple processed.
Optimized Markov state models for metastable systems
Authors: Guarnera Enrico , Vanden-Eijnden Eric
Published: July 2016

A method is proposed to identify target states that optimize a metastability index amongst a set of trial states and use these target states as milestones (or core sets) to build Markov State Models (MSMs). If the optimized metastability index is small, this automatically guarantees the accuracy of the MSM, in the sense that the transitions between the target milestones is indeed approximately Markovian. The method is simple to implement and use, it does not require that the dynamics on the trial milestones be Markovian, and it also offers the possibility to partition the system’s state-space by assigning every trial milestone to the target milestones it is most likely to visit next and to identify transition state regions. Here the method is tested on the Gly-Ala-Gly peptide, where it is shown to correctly identify the expected metastable states in the dihedral angle space of the molecule without a priori information about these states. It is also applied to analyze the folding landscape of the Beta3s mini-protein, where it is shown to identify the folded basin as a connecting hub between an helix-rich region, which is entropically stabilized, and a beta-rich region, which is energetically stabilized and acts as a kinetic trap.
Hierarchy of forward-backward stochastic Schrödinger equation
Authors: Ke Yaling , Zhao Yi
Published: July 2016

Driven by the impetus to simulate quantum dynamics in photosynthetic complexes or even larger molecular aggregates, we have established a hierarchy of forward-backward stochastic Schrödinger equation in the light of stochastic unravelling of the symmetric part of the influence functional in the path-integral formalism of reduced density operator. The method is numerically exact and is suited for Debye-Drude spectral density, Ohmic spectral density with an algebraic or exponential cutoff, as well as discrete vibrational modes. The power of this method is verified by performing the calculations of time-dependent population differences in the valuable spin-boson model from zero to high temperatures. By simulating excitation energy transfer dynamics of the realistic full FMO trimer, some important features are revealed.
Elliptically polarized electromagnetic waves in a magnetized quantum electron-positron plasma with effects of exchange-correlation
Authors: Shahmansouri M. , Misra A. P.
Published: July 2016

The dispersion properties of elliptically polarized electromagnetic waves in a magnetized electron-positron-pair (EP-pair) plasma are studied with the effects of particle dispersion associated with the Bohm potential, the Fermi degenerate pressure, and the exchange-correlation force. Two possible modes of the extraordinary or X wave, modified by these quantum effects, are identified and their propagation characteristics are investigated numerically. It is shown that the upper-hybrid frequency and the cutoff and resonance frequencies are no longer constants but are dispersive due to these quantum effects. It is found that the particle dispersion and the exchange-correlation force can have different dominating roles on each other depending on whether the X waves are of short or long wavelengths (in comparison with the Fermi Debye length). The present investigation should be useful for understanding the collective behaviors of EP plasma oscillations and the propagation of extraordinary waves in magnetized dense EP-pair plasmas.
Temperature characteristics of epitaxially grown InAs quantum dot micro-disk lasers on silicon for on-chip light sources
Authors: Wan Yating , Li Qiang , Liu Alan Y. , Gossard Arthur C. , Bowers John E. , Hu Evelyn L. , Lau Kei May
Published: July 2016

Temperature characteristics of optically pumped micro-disk lasers (MDLs) incorporating InAs quantum dot active regions are investigated for on-chip light sources. The InAs quantum dot MDLs were grown on V-groove patterned (001) silicon, fully compatible with the prevailing complementary metal oxide-semiconductor technology. By combining the high-quality whispering gallery modes and 3D confinement of injected carriers in quantum dot micro-disk structures, we achieved lasing operation from 10 K up to room temperature under continuous optical pumping. Temperature dependences of the threshold, lasing wavelength, slope efficiency, and mode linewidth are examined. An excellent characteristic temperature To of 105 K has been extracted.
Electric field stimulated growth of Zn whiskers
Authors: Niraula D. , McCulloch J. , Warrell G. R. , Irving R. , Karpov V. G. , Shvydka Diana
Published: July 2016

We have investigated the impact of strong (∼104 V/cm) electric fields on the development of Zn whiskers. The original samples, with considerable whisker infestation were cut from Zn-coated steel floors and then exposed to electric fields stresses for 10-20 hours at room temperature. We used various electric field sources, from charges accumulated in samples irradiated by: (1) the electron beam of a scanning electron microscope (SEM), (2) the electron beam of a medical linear accelerator, and (3) the ion beam of a linear accelerator; we also used (4) the electric field produced by a Van der Graaf generator. In all cases, the exposed samples exhibited a considerable (tens of percent) increase in whiskers concentration compared to the control sample. The acceleration factor defined as the ratio of the measured whisker growth rate over that in zero field, was estimated to approach several hundred. The statistics of lengths of e-beam induced whiskers was found to follow the log-normal distribution known previously for metal whiskers. The observed accelerated whisker growth is attributed to electrostatic effects. These results offer promise for establishing whisker-related accelerated life testing protocols.
Tuning the composition of ternary Bi2Se3xTe3(1-x) nanoplates and their Raman scattering investigations
Authors: Wu Peng , Chen Haiping , Yang Chao , Gan Wei , Muhammad Zahir , Song Li
Published: July 2016

We present the composition engineering and Raman scattering study of Bi2Se3xTe3(1-x) nanoplates that were synthesized by chemical vapor deposition method using different substrates, including fluorophlogopite mica, SiO2/Si. The characterizations revealed high crystallinity and layered-structure in the ternary Bi2Se3xTe3(1-x) products. Raman spectra of Bi2Se3xTe3(1-x) ranging from 80-200 cm-1 as a function of different Se-doping levels shows that intrinsic Raman peaks of Bi2Se3xTe3(1-x) nanoplates shift to higher frequency as the ratio of doped-Se increasing. The discontinuity of Raman peaks was found and discussed.
A phrase-frame approach to investigating phraseology in learner writing across proficiency levels
Authors: Garner James R.
Published: July 2016

Findings from corpus-based and psycholinguistic research have highlighted the importance of acquiring productive knowledge of English phraseology for L2 learners. Many studies exploring this facet of language learning have investigated the use of predominantly fixed multi-word sequences by advanced learners in academic settings and compared their use against that of native-speaking writers. More recent studies have attempted to explore the differences between learners’ use of multi-word sequences across proficiency levels. The current study aims to add to this growing body of literature. It examines the use of phrase-frames by L1 German learners of English as a Foreign Language at five different proficiency levels represented in theEF-Cambridge Open Language Database(EFCAMDAT). The most frequent phrase-frames in each level are analyzed according to both quantitative and qualitative characteristics. The results revealed that, at higher proficiency levels, p-frames in learner texts are more variable, less predictable, and more functionally complex.
TheKansas Developmental Learner corpus(KANDEL)
Authors: Vyatkina Nina
Published: July 2016

This article presents theKansas Developmental Learner corpus(KANDEL), a corpus of L2 German writing samples produced by several cohorts of North American university students over four semesters of instructed language study. This corpus expands the number of freely and publicly available learner corpora while adding to the depth of these corpora with a unique set of features. It does so by focusing on an L2 other than English, German, targeting beginning to intermediate L2 proficiency levels, and including dense developmental data and annotations for multiple linguistic variables, learner errors, and over twenty learner and task variables. Furthermore, this article reports the procedure and results of an inter-annotator agreement study as well as an in-depth analysis of annotator disagreement. In this way, it contributes to best practices of annotating learner corpora by making the annotation process transparent and demonstrating its reliability.
Different Migratory Strategies of Invasive Common Carp and Native Northern Pike in the American Midwest Suggest an Opportunity for Selective Management Strategies
Authors: Chizinski Christopher J. , Bajer Przemyslaw G. , Headrick Mary E. , Sorensen Peter W.
Published: July 2016

Inundated floodplains, backwaters, and wetlands are important spawning habitats for many freshwater fish. In Midwestern North America and areas of northern Europe, the Common Carp Cyprinus carpio and Northern Pike Esox lucius inhabit many of the same watersheds and perform migrations to interconnected wetlands during the spring to spawn. In this study, the movement patterns of adult Northern Pike and Common Carp from lakes into adjoining wetlands were assessed in Minnesota to determine how and when these species moved, and if Common Carp might be blocked or trapped without disrupting the Northern Pike. Adult Northern Pike migrated over an extended several-week period starting early each March, when temperatures were greater than 4ºC and when the fish were fully sexually mature (i.e., females were ovulated and running with eggs, and males were spermiating). In contrast, adult Common Carp migrated over relatively short time periods that lasted just a few days between April and June, and whose specific timing varied but always occurred after water temperatures rose to 10ºC and usually coincided with rain. Migrating Common Carp were in prespawning condition (i.e., females were not yet ovulated) and appeared to be homing as stream selection was very specific. Less than half of the Common Carp population migrated each year, reinforcing earlier observations that Common Carp likely conduct partial migrations. Overlap between Northern Pike and Common Carp was minimal, suggesting that management strategies using removable barriers, for example, could be used to control invasive Common Carp without affecting native Northern Pike populations.

Received August 12, 2015; accepted March 11, 2016 Published online July 8, 2016
When does inequality freeze an economy?
Authors: Jerico João Pedro , Landes François P , Marsili Matteo , Pérez Castillo Isaac , Volpati Valerio
Published: July 2016

Inequality and its consequences are the subject of intense recent debate. Using a simplified model of the economy, we address the relation between inequality and liquidity, the latter understood as the frequency of economic exchanges. Assuming a Pareto distribution of wealth for the agents, that is consistent with empirical findings, we find an inverse relation between wealth inequality and overall liquidity. We show that an increase in the inequality of wealth results in an even sharper concentration of the liquid financial resources. This leads to a congestion of the flow of goods and the arrest of the economy when the Pareto exponent reaches one.
White dwarf pollution by planets in stellar binaries
Authors: Hamers Adrian S. , Portegies Zwart Simon F.
Published: July 2016

Approximately 0.2 ± 0.2 of white dwarfs (WDs) show signs of pollution by metals, which is likely due to the accretion of tidally disrupted planetary material. Models invoking planet–planet interactions after WD formation generally cannot explain pollution at cooling times of several Gyr. We consider a scenario in which a planet is perturbed by Lidov–Kozai oscillations induced by a binary companion and exacerbated by stellar mass-loss, explaining pollution at long cooling times. Our computed accretion rates are consistent with observations assuming planetary masses between ∼0.01 and 1 MMars, although non-gravitational effects may already be important for masses ≲0.3 MMars. The fraction of polluted WDs in our simulations, ∼0.05, is consistent with observations of WDs with intermediate cooling times between ∼0.1 and 1 Gyr. For cooling times ≲0.1 Gyr and ≳1 Gyr, our scenario cannot explain the high observed pollution fractions of up to 0.7. Nevertheless, our results motivate searches for companions around polluted WDs.
Optimal Treatment for Complicated Intra-abdominal Infections in the Era of Antibiotic Resistance: A Systematic Review and Meta-Analysis of the Efficacy and Safety of Combined Therapy With Metronidazole
Authors: Mikamo Hiroshige , Yuasa Akira , Wada Keiko , Crawford Bruce , Sugimoto Naomi
Published: July 2016

Background.  Carbapenem-resistant Enterobacteriaceae has increased dramatically in the last decade, resulting in infections that are difficult to treat and associated with high mortality rates. To prevent further antibacterial resistance, it is necessary to use carbapenem selectively. A combination of metronidazole with an antimicrobial agent active against aerobes is an alternative effective treatment for patients with complicated intra-abdominal infections (cIAIs). This study aimed to compare efficacy and safety of metronidazole combination therapies and carbapenem and to provide clinical evidence regarding the optimal treatment of cIAI.

Methods.  A systematic review and a meta-analysis of randomized clinical trials in the treatment of cIAI were conducted. The systematic review with PubMed, Embase, and the Cochrane Database of Systematic Reviews followed the Cochrane Handbook's recommended methodology, and the meta-analysis used a Mantel-Haenszel random-effects model with RevMan, version 5.3. Primary endpoints were clinical success and bacteriological eradication, and secondary endpoints were all-cause mortality and drug-related adverse events.

Results.  Eight studies comparing metronidazole combination therapies and carbapenem were included in the meta-analysis. No difference was found between combined therapy with metronidazole and carbapenem regarding clinical success (odds ratio [OR] = 1.31; 95% confidence interval [CI], .75–2.31), bacteriological eradication (OR = 1.27; 95% CI, .84–1.91), all-cause mortality (OR = 0.61; 95% CI, .37–1.00), or drug-related adverse events (OR = 0.58; 95% CI, .18–1.88). Sensitivity analyses found similar results.

Conclusions.  Combined therapy with metronidazole is as effective and safe as carbapenem in treatment of cIAI. Therefore, combined therapy with metronidazole offers an effective alternative to carbapenem with low risk of drug resistance.
Evaluation of a Multilocus Indel DNA Region for the Detection of the Wheat Tan Spot Pathogen Pyrenophora tritici-repentis
Authors: See Pao Theen , Moffat Caroline S. , Morina Joseph , Oliver Richard P.
Published: July 2016

Tan spot or yellow (leaf) spot disease of wheat (Triticum spp.) is caused by Pyrenophora tritici-repentis, a necrotrophic fungal pathogen that is widespread throughout the main wheat-growing regions in the world. This disease is currently the single most economically important crop disease in Australia. In this study, a real-time quantitative polymerase chain reaction (qPCR) assay was developed as a diagnostic tool to detect the pathogen on wheat foliar tissue. A multicopy locus (PtrMulti) present in the P. tritici-repentis genome was assessed for its suitability as a qPCR probe. The primer pair PtrMulti_F/R that targets the region was evaluated with respect to species specificity and sensitivity. A PtrMulti SYBR qPCR assay was developed and proved to be suitable for the identification and relative quantification of P. tritici-repentis with a detection limit of DNA levels at <0.1 pg. Variation of the PtrMulti copy number between the geographical representatives of P. tritici-repentis strains examined was minimal, with the range of 63 to 85 copies per genome. For naturally infected wheat field samples, the incidence of P. tritici-repentis DNA on leaves quantified by qPCR varied up to 1,000-fold difference in the concentration, with a higher incidence of DNA occurring on the lower canopy for most of the growth stages examined. At the early growth stages, qPCR assay was able to detect P. tritici-repentis DNA on the younger leaves in the absence of visible tan spot lesions. These results demonstrate the potential of PtrMulti probe to be used for early detection and rapid screening of tan spot disease on wheat plants.
Sensitivity of Phakopsora pachyrhizi Isolates to Fungicides and Reduction of Fungal Infection Based on Fungicide and Timing of Application
Authors: Twizeyimana M. , Hartman G. L.
Published: July 2016

Soybean rust (SBR), caused by Phakopsora pachyrhizi, is a damaging foliar fungal disease in many soybean-growing areas of the world. Strategies to manage SBR include the use of foliar fungicides. Fungicide types, the rate of product application, and the number and timing of applications are critical components for successful rust management. The objectives of this study were to determine i) the sensitivity of P. pachyrhizi isolates collected in the U.S. to a range of fungicides and ii) the reduction of fungal infection based on fungicide type and timing of applications on soybean. There were differences (P < 0.05) in effective concentration (EC50) values among the fungicides tested. Azoxystrobin had low EC50 values for both urediniospore germination and fungal sporulation on inoculated leaflets. There were differences (P < 0.05) in fungal sporulation for application times, fungicide treatments, and their interaction when the fungus was inoculated on plants. All application times and nearly all fungicide treatments reduced (α = 0.05) fungal infection compared with the nonfungicide control. Information on fungicide sensitivity of P. pachyrhizi isolates and the preventive and curative effects of different fungicides are important in the management of SBR.
Effectiveness of Chemical Compounds and Biocontrol Agents for Management of Bacterial Spot of Pumpkin Caused by Xanthomonas cucurbitae
Authors: Thapa Sita , Babadoost Mohammad
Published: July 2016

Bacterial spot, caused by Xanthomonas cucurbitae, has become one of the most important diseases of pumpkin. Seventeen chemical compounds and five biocontrol agents were evaluated for their efficacy for management of the disease. The EC50 for reduction in cell multiplication of the pathogen ranged from 0.17 ppm for mancozeb (Dithane 75 DF) to 64.53 ppm for cuprous oxide (Nordox 75 WG) in nutrient broth, and from 0.23 ppm for Dithane 75 DF to 38.87 ppm Nordox 75 WG in casitone yeast extract broth. The inhibition zones produced by biocontrol agents on Luria Bertani culture medium ranged from 3.1 mm for Bacillus pumilus (Sonata ASO) to 10.6 mm for Streptomyces lydicus (Actinovate AG). In the field trials, copper oxychloride + copper hydroxide (Badge X2 DF), copper sulfate (Cuprofix Ultra 40 DF), oxytetracycline (Mycoshield 40 WSP), copper sulfate pentahydrate (Phyton-016B), copper hydroxide (Kocide-3000 46.1 DF) plus acibenzolar-s-methyl (ActiGard 50 WG), Kocide-3000 46.1 DF plus famoxadone + cymoxanil (Tanos 50D WG), an extract from Reynoutria sachalinensis (Regalia), and B. subtilis (Serenade ASO) were more effective in reducing incidence and severity of bacterial spot on both leaves and fruit compared to controls. These chemical compounds or biocontrol agents may be used in combination with other methods to manage X. cucurbitae in pumpkin.

Accepted for publication 19 April 2016. Published 9 May 2016.
Cercospora zeinafrom Maize in South Africa Exhibits High Genetic Diversity and Lack of Regional Population Differentiation
Authors: Muller Mischa F. , Barnes Irene , Kunene Ncobile T. , Crampton Bridget G. , Bluhm Burton H. , Phillips Sonia M. , Olivier Nicholas A. , Berger Dave K.
Published: July 2016

South Africa is one of the leading maize-producing countries in sub-Saharan Africa. Since the 1980s, Cercospora zeina, a causal agent of gray leaf spot of maize, has become endemic in South Africa, and is responsible for substantial yield reductions. To assess genetic diversity and population structure of C. zeina in South Africa, 369 isolates were collected from commercial maize farms in three provinces (KwaZulu-Natal, Mpumalanga, and North West). These isolates were evaluated with 14 microsatellite markers and species-specific mating type markers that were designed from draft genome sequences of C. zeina isolates from Africa (CMW 25467) and the United States (USPA-4). Sixty alleles were identified across 14 loci, and gene diversity values within each province ranged from 0.18 to 0.35. High levels of gene flow were observed (Nm = 5.51), and in a few cases, identical multilocus haplotypes were found in different provinces. Overall, 242 unique multilocus haplotypes were identified with a low clonal fraction of 34%. No distinct population clusters were identified using STRUCTURE, principal coordinate analysis, or Weir’s theta θ statistic. The lack of population differentiation was supported by analysis of molecular variance tests, which indicated that only 2% of the variation was attributed to variability between populations from each province. Mating type ratios of MAT1-1 and MAT1-2 idiomorphs from 335 isolates were not significantly different from a 1:1 ratio in all provinces, which provided evidence for sexual reproduction. The draft genome of C. zeina CMW 25467 exhibited a complete genomic copy of the MAT1-1 idiomorph as well as exonic fragments of MAT genes from both idiomorphs. The high level of gene diversity, shared haplotypes at different geographical locations within South Africa, and presence of both MAT idiomorphs at all sites indicates widespread dispersal of C. zeina between maize fields in the country as well as evidence for sexual recombination. The outcomes of this genome-enabled study are important for disease management since the high diversity has implications for dispersal of fungicide resistance should it emerge and the need for diversified resistance breeding.
Sacred Spaces
Authors: Brelsford Gina M. , Ramirez Joshua , Veneman Kristin , Doheny Kim K.
Published: July 2016

Background:

Preterm birth is an unanticipated and stressful event for parents. In addition, the unfamiliar setting of the intensive care nursery necessitates strategies for coping.

Purpose:

The primary study objective of this descriptive study was to determine whether secular and religious coping strategies were related to family functioning in the neonatal intensive care unit.

Methods:

Fifty-two parents of preterm (25-35 weeks' gestation) infants completed the Brief COPE (secular coping), the Brief RCOPE (religious coping), and the Family Environment Scale within 1 week of their infant's hospital admission.

Findings:

This descriptive study found that parents' religious and secular coping was significant in relation to family relationship functioning. Specifically, negative religious coping (ie, feeling abandoned or angry at God) was related to poorer family cohesion and use of denial.

Implications for Practice:

These findings have relevance for interventions focused toward enhancing effective coping for families.

Implications for Research:

Further study of religious and secular coping strategies for neonatal intensive care unit families is warranted in a larger more diverse sample of family members.
Surveillance and Isolation of Methicillin-Resistant Staphylococcus aureus Colonization in the Neonatal Intensive Care Unit
Authors: Newnam Katherine M.
Published: July 2016

Background:

Neonatal sepsis causes 1.4 million (36%) neonatal deaths annually. Staphylococcus aureus (SA), a common skin pathogen, remains the second leading cause of late-onset sepsis in the neonatal intensive care unit (NICU). Methicillin-resistant Staphylococcus aureus (MRSA), a resistant strain of SA, has created a significant global communicable health risk, especially in the NICU.

Purpose:

To examine evidence related to NICU infection control practices surrounding MRSA surveillance, identification, and isolation in response to the clinical question, “What strategies should be universally implemented in the NICU to identify and prevent the spread of MRSA?”

Methods/Search Strategy:

Databases were examined for articles on the topical area of MRSA in the neonate. Key terms were used to streamline the search, resulting in 20 primary works and 3 guideline/consensus statements considered imperative in response to the clinical questions.

Findings/Results:

Hand hygiene remains the cornerstone to sound infection control practice. Colonization often leads to systemic infection, with smaller neonates at greatest risk. Hospital infection control compliance has improved outcomes. MRSA surveillance has reduced horizontal spread. No universal, specific recommendations exist to guide surveillance and management of MRSA in the NICU.

Implications for Practice:

Standardized guidelines with procedures for hand hygiene, patient surveillance and isolation, and patient cohorting with recommended staffing patterns should guide practice in the NICU. Both MRSA culture and polymerase chain reaction effectively identify positive patients. Decolonization practices are not yet clear.

Implications for Research:

Evaluation of standard isolation practices versus outbreak response and approaches to neonatal decolonization should be evaluated for efficacy, safety, and resistance.
Fertility Treatments in the United States
Authors: Kissin Dmitry M. , Boulet Sheree L. , Jamieson Denise J. ,   for the Assisted Reproductive Technology Surveillance and Research Team
Published: July 2016

The recently released National Public Health Action Plan for the Detection, Prevention, and Management of Infertility calls for better access to high-quality infertility services and improved safety of fertility treatments. Both assisted reproductive technology (ART) and non-ART fertility treatments have allowed millions of patients worldwide to overcome infertility—a disease of the reproductive system and important public health issue. However, there are substantial disparities in access to effective treatments in the United States, largely attributable to high out-of-pocket costs, especially for ART. Moreover, the outcomes of fertility treatments are often complicated by the large proportion of multiple births with substantial health risks for both neonates and mothers. Prevention of multiple births is difficult during non-ART fertility treatments but can be effective with single-embryo transfer during ART. Several U.S. states have enacted legislative mandates that require private insurers to cover some portion of the costs associated with fertility treatments and thus reduce the financial pressure to transfer multiple embryos during ART. Although studies have shown that insurance coverage reduces per-cycle multiple births to a certain degree, states with insurance mandates have more ART-related multiple births attributable to substantially larger number of ART-conceived neonates. Experience from other countries shows that access to ART can be improved without concomitant increases in multiple births by providing reimbursement for ART in combination with restrictions on the number of embryos transferred per cycle. Such approaches may or may not be successful in the United States with its unique and complex health care system.
Sacral Neuromodulation for the Treatment of Persistent Genital Arousal Disorder
Authors: Jones Christina L. , Fischer John R. , Hernandez Sandra L.
Published: July 2016

BACKGROUND:

Patients affected with persistent genital arousal disorder report unprovoked, excessive, and unremitting genital arousal unrelated to sexual desire. Those afflicted experience severe physical and psychological distress with significant feelings of shame, guilt, and frustration. Definitive treatment options for this disorder are limited.

CASE:

We present the case of a 32-year-old woman, gravida 1 para 1, with persistent genital arousal disorder after treatment of an uncomplicated urinary tract infection while in a military-deployed environment. After numerous treatment modalities failed, she responded to an implanted sacral neuromodulator.

CONCLUSION:

Persistent genital arousal disorder may be the result of upregulated sacral nerve pathways. We report the use of sacral neuromodulation using unique program settings, which may be an effective alternative in the treatment of this distressing disorder.
Phenazopyridine for Evaluation of Ureteral Patency
Authors: Propst Katie , Tunitsky-Bitton Elena , O'Sullivan David M. , Steinberg Adam C. , LaSala Christine
Published: July 2016

OBJECTIVE:

To evaluate the usefulness of phenazopyridine for confirmation of ureteral patency during intraoperative cystoscopy.

METHODS:

We conducted a randomized controlled trial comparing use of phenazopyridine with no medications for evaluation of ureteral patency during intraoperative cystoscopy in women undergoing pelvic surgery. The primary study outcome was time to visualize ureteral urine efflux. To detect a 3-minute difference with α of 0.05 using a two-sided, two-sample t test and β 0.80 required 98 patients equally divided into two groups.

RESULTS:

A total of 104 women were randomized from April to December 2015. Patients in the treatment group tended to be older (P=.02); otherwise, study groups were similar. Time to visualize ureteral urine efflux did not differ between study groups with a mean time of 2 minutes 40 seconds (±2 minutes 38 seconds) in the control group and 2 minutes 53 seconds (±4 minutes 35 seconds) in the treatment group (P=.77). Regarding the surgeon survey, surgeons felt less frustrated and impatient in visualization of ureteral urine efflux in the treatment group compared with the control group (mean response 1.5±0.8 in treatment compared with 2.0±1.0 in control, P=.007), and surgeons felt that the cystoscopy took too long more often in the control than in the treatment group (1.7±0.9 in treatment compared with 2.1±1.0 in control, P=.02). Trial of void result differed significantly between groups with fewer patients in the treatment group failing a void trial (P=.04). There were no adverse events related to phenazopyridine use.

CONCLUSION:

Preoperative phenazopyridine is a useful and cost-saving medication for use in planned cystoscopy for evaluation of ureteral patency.

CLINICAL TRIAL REGISTRATION:

ClinicalTrials.gov, https://clinicaltrials.gov/, NCT02424149.
Rethinking the Bioethics of Pregnancy
Authors: Premkumar Ashish , Gates Elena
Published: July 2016

Within the realm of bioethics, the construction of pregnancy classically has focused on principle-based ethics, essentially separating maternal and fetal interests. Respect for maternal autonomy becomes distinct from an obligation of fetal beneficence, placing practitioners in complicated ethical situations when the goals of pregnant women may be at odds with the best health interests of the fetus as defined by both professional groups and society in general. As a result, clinical care is framed by an ethical “maternal–fetal conflict,” with important downstream legal and policy consequences for the well-being of pregnant women. Developments in the social sciences highlight the value of attending to the biosocial realm that a pregnant woman inhabits rather than relating to her and to her fetus as discrete entities. By understanding the needs, concerns, and context within which a woman lives, clinicians can practice an ethics of accompaniment. With a focus on an ethics of accompaniment, assumptions about the maternal moral responsibility to fetal health made by practitioners and society in general can directly affect not only clinical care, but also the way policy surrounding reproductive health is constructed and implemented.