bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of indigenous and exotic×indigenous sheep breeds fed different diets in spring and the efficiency of feeding system in crop–livestock farming
Authors: ATES S. , KELES G. , INAL F. , GUNES A. , DHEHIBI B.
Published: July 2014

Genetic variation in feed efficiency may have a significant impact on sheep production in integrated crop livestock farming systems in dry areas, where the shortage and poor quality of feed is widespread. Thus, the present study was carried out to investigate the effects of sheep genotype and feed source on liveweight gain, feed conversion efficiency and dry matter (DM) intake in feedlot lambs finished on diets based on low-cost forages or a high-cost concentrated feed as a means of assessing the efficiency of this feeding system. Early weaned lambs of the purebred fat-tailed Akkaraman breed were compared with synthetic Anatolian Merino (0·80 German Mutton Merino×0·20 Native Akkaraman) breed. The lambs were kept in individual pens for 8 weeks and fed four diets: daily harvested forages of triticale (T), Hungarian vetch (HV), a triticale-Hungarian vetch mixture (T+HV), and a concentrate-based feed (CF). Lamb liveweight gain (LWG) was monitored during the early (18 April–16 May) and late (17 May–13 June) spring periods. Diet×period and diet×breed interactions were detected in LWG of the lambs. Lambs from both genotypes on the concentrate-based diet had higher liveweight gains, DM intakes and better feed conversion ratios compared with lambs finished on the forage-based diets. The LWG of lambs offered triticale forage decreased from 177 g/head/day in the early spring to 95 g/head/day in the late spring period, as plant maturity increased. Liveweight gains did not change for the other forage rations during the same period. The LWG of Akkaraman lambs were similar for both the early (189 g/head/day) and the late (183 g/head/day) spring periods, whereas Anatolian Merino lambs gained 41 g/head/day less LW and had 3·8 higher feed conversion rate for the late spring period compared with the early spring period. The present study showed that fat-tailed Akkaraman lambs were better able to utilize forages with low nutritive value compared to Anatolian Merino lambs, and may be better suited to semi-arid areas, where crop and livestock are highly integrated in the farming system.
Cortical thickness and inattention/hyperactivity symptoms in young children: a population-based study
Authors: Mous S. E. , Muetzel R. L. , El Marroun H. , Polderman T. J. C. , van der Lugt A. , Jaddoe V. W. , Hofman A. , Verhulst F. C. , Tiemeier H. , Posthuma D. , White T.
Published: July 2014

Background.

While many neuroimaging studies have investigated the neurobiological basis of attention deficit hyperactivity disorder (ADHD), few have studied the neurobiology of attention problems in the general population. The ability to pay attention falls along a continuum within the population, with children with ADHD at one extreme of the spectrum and, therefore, a dimensional perspective of evaluating attention problems has an added value to the existing literature. Our goal was to investigate the relationship between cortical thickness and inattention and hyperactivity symptoms in a large population of young children.

Method.

This study is embedded within the Generation R Study and includes 6- to 8-year-old children (n = 444) with parent-reported attention and hyperactivity measures and high-resolution structural imaging data. We investigated the relationship between cortical thickness across the entire brain and the Child Behavior Checklist Attention Deficit Hyperactivity Problems score.

Results.

We found that greater attention problems and hyperactivity were associated with a thinner right and left postcentral gyrus. When correcting for potential confounding factors and multiple testing, these associations remained significant.

Conclusions.

In a large, population-based sample we showed that young (6- to 8-year-old) children who show more attention problems and hyperactivity have a thinner cortex in the region of the right and left postcentral gyrus. The postcentral gyrus, being the primary somatosensory cortex, reaches its peak growth early in development. Therefore, the thinner cortex in this region may reflect either a deviation in cortical maturation or a failure to reach the same peak cortical thickness compared with children without attention or hyperactivity problems.
Political diversity will improve social psychological science
Authors: Duarte José L. , Crawford Jarret T. , Stern Charlotta , Haidt Jonathan , Jussim Lee , Tetlock Philip E.
Published: July 2014

Psychologists have demonstrated the value of diversity – particularly diversity of viewpoints – for enhancing creativity, discovery, and problem solving. But one key type of viewpoint diversity is lacking in academic psychology in general and social psychology in particular: political diversity. This article reviews the available evidence and finds support for four claims: (1) Academic psychology once had considerable political diversity, but has lost nearly all of it in the last 50 years. (2) This lack of political diversity can undermine the validity of social psychological science via mechanisms such as the embedding of liberal values into research questions and methods, steering researchers away from important but politically unpalatable research topics, and producing conclusions that mischaracterize liberals and conservatives alike. (3) Increased political diversity would improve social psychological science by reducing the impact of bias mechanisms such as confirmation bias, and by empowering dissenting minorities to improve the quality of the majority's thinking. (4) The underrepresentation of non-liberals in social psychology is most likely due to a combination of self-selection, hostile climate, and discrimination. We close with recommendations for increasing political diversity in social psychology.
WiFi SLAM algorithms: an experimental comparison
Authors: Herranz F. , Llamazares A. , Molinos E. , Ocaña M. , Sotelo M. A.
Published: July 2014

Localization and mapping in indoor environments, such as airports and hospitals, are key tasks for almost every robotic platform. Some researchers suggest the use of Range-Only (RO) sensors based on WiFi (Wireless Fidelity) technology with SLAM (Simultaneous Localization And Mapping) techniques to solve both problems. The current state of the art in RO SLAM is mainly focused on the filtering approach, while the study of smoothing approaches with RO sensors is quite incomplete. This paper presents a comparison between filtering algorithms, such as EKF and FastSLAM, and a smoothing algorithm, the SAM (Smoothing And Mapping). Experimental results are obtained in indoor environments using WiFi sensors. The results demonstrate the feasibility of the smoothing approach using WiFi sensors in an indoor environment.
Optimization and analysis of a redundant 4R spherical wrist mechanism for a shoulder exoskeleton
Authors: Lo Ho Shing , Xie Shengquan
Published: July 2014

This paper presents a redundant 4-revolute (4R) spherical wrist mechanism for a shoulder exoskeleton, which overcomes several major issues with the 3R mechanisms used in the past. An analysis of the 3R mechanism is done to highlight the limitations in its range of motion and problems caused by operating near singular configurations. To ensure that the redundancy in the 4R mechanism is efficiently utilized, genetic algorithm is used to optimize the mechanism design and identify the optimal operating configurations of the mechanism. The capability to reach the entire shoulder workspace is guaranteed and the joint velocities are minimized by considering the joint displacements required to move the end-effector throughout the workspace and the condition number of joint configurations for reaching 89 positions in the workspace. Analysis of the 4R mechanism obtained from the optimization process indicates that it can move throughout the entire shoulder workspace with feasibly low joint velocities.
From disaster to sustainability: floods, changing property relations and water management in the south-western Netherlands, c.1500–1800
Authors: VAN CRUYNINGEN PIET
Published: July 2014

When large parts of the south-western Netherlands flooded in the fifteenth and sixteenth centuries the main cause was insufficient maintenance of the sea defences. The subsequent re-embankment of the polders resulted in changes to both soil conditions and property relations in the region. The Church and the local peasants lost land and members of the urban bourgeoisie became the most important landowners. Unlike their risk-averse predecessors, these capitalist landlords were prepared to invest in drainage. They were also able to organise state support for those polders that were at risk of flooding. Tenant and yeomen farmers had an equally important role as they maintained the fertility of the soil and were prepared to invest in the upkeep of the flood defences.
Governing Prostitution: New Formations, Old Agendas
Authors: Phoenix Jo
Published: July 2014

Les travaux récents sur la gouvernementalité distinguent comment celle-ci peut s'exercer «d'en haut» comme «d'en bas» afin d'éviter des analyses verticales de l'État et de reconnaître les modalités multiples d'expression de ce pouvoir. En analysant des mutations clé de la régulation de la prostitution au Royaume-Uni depuis trois décennies, il est possible de compliquer la distinction entre ces deux modes de gouvernance. Bien que plusieurs auteurs soulignent que la distinction est de plus en plus brouillée entre ces deux modes, nous soutenons que s'il est difficile de débrouiller les programmes de gouvernement «d'en haut» et «d'en bas», ce n'est guère le cas dès qu'il s'agit des conséquences sur les travailleuses du sexe. La régulation demeure enracinée dans les réactions coercitives et punitives de la justice pénale, même si les associations «d'en bas» peuvent être chargées par l'État de les exécuter.
Echoes of Imprisonment: Women's Experiences of “Successful (Re)integration”
Authors: Shantz Laura , Kilty Jennifer M. , Frigon Sylvie
Published: July 2014

Les femmes qui sortent de prison continuent de faire face à des épreuves provenant de leur emprisonnement. Dans cet article, nous abordons les façons dont la prison, et par extension l'État, suivent les femmes à l'extérieur de la prison jusque dans leurs communautés. Tandis que l'État tente d'assurer une réintégration réussie des ex-prisonnières, ses politiques, reflétant un agenda néolibéral de responsabilisation individuelle, entravent possiblement les chances des femmes de réintégrer leurs communautés. Ici, nous explorons les expériences de (ré)intégration des femmes par l'entremise de témoignages d'ex-prisonnières ayant servi de longues sentences, de leur famille et de leurs défenseurs. Le contrôle que ces femmes ont connu en prison résonne dans leur vie après leur mise en liberté: elles ressentent une désagrégation, une marginalisation et un besoin de (re)négocier leur vie. Tandis que les femmes peuvent quitter la prison, le contrôle qu'elles ont subi durant leur incarcération demeure imprégné dans leur esprit et leur corps. L'État continue d'exercer, bref, une autorité sur elles à distance par les séquelles de leur emprisonnement ainsi que par une surveillance continue.
“Brain Death,” “Dead,” and Parental Denial
Authors: PARIS JOHN J. , CUMMINGS BRIAN M. , MOORE M. PATRICK
Published: July 2014

This section provides reactions to current and emerging issues in bioethics.
Dignity and the Ownership and Use of Body Parts
Authors: FOSTER CHARLES
Published: July 2014

Property-based models of the ownership of body parts are common. They are inadequate. They fail to deal satisfactorily with many important problems, and even when they do work, they rely on ideas that have to be derived from deeper, usually unacknowledged principles. This article proposes that the parent principle is always human dignity, and that one will get more satisfactory answers if one interrogates the older, wiser parent instead of the younger, callow offspring. But human dignity has a credibility problem. It is often seen as hopelessly amorphous or incurably theological. These accusations are often just. But a more thorough exegesis exculpates dignity and gives it its proper place at the fountainhead of bioethics. Dignity is objective human thriving. Thriving considerations can and should be applied to dead people as well as live ones. To use dignity properly, the unit of bioethical analysis needs to be the whole transaction rather than (for instance) the doctor-patient relationship. The dignity interests of all the stakeholders are assessed in a sort of utilitarianism. Its use in relation to body part ownership is demonstrated. Article 8(1) of the European Convention of Human Rights endorses and mandates this approach.
Characterization of freshly retrieved preantral follicles using a low-invasive, mechanical isolation method extended to different ruminant species
Authors: Langbeen A. , Jorssen E.P.A. , Fransen E. , Rodriguez A.P.A. , García M. Chong , Leroy J.L.M.R. , Bols P.E.J.
Published: July 2014

Due to the increased interest in preantral follicular physiology, non-invasive retrieval and morphological classification are crucial. Therefore, this study aimed: (1) to standardize a minimally invasive isolation protocol, applicable to three ruminant species; (2) to morphologically classify preantral follicles upon retrieval; and (3) to describe morphological features of freshly retrieved follicles compared with follicle characteristics using invasive methods. Bovine, caprine and ovine ovarian cortex strips were retrieved from slaughterhouse ovaries and dispersed. This suspension was filtered, centrifuged, re-suspended and transferred to a Petri dish, to which 0.025 mg/ml neutral red (NR) was added to assess the viability of the isolated follicles. Between 59 and 191 follicles per follicle class and per species were collected and classified by light microscopy, based on follicular cell morphology. Subsequently, follicle diameters were measured. The proposed isolation protocol was applicable to all three species and showed a significant, expected increase in diameter with developmental stage. With an average diameter of 37 ± 5 μm for primordial follicles, 47 ± 6.3 μm for primary follicles and 67.1 ± 13.1 μm for secondary follicles, no significant difference in diameter among the three species was observed. Bovine, caprine and ovine follicles (63, 59 and 50% respectively) were graded as viable upon retrieval. Using the same morphological characteristics as determined by invasive techniques [e.g. haematoxylin–eosin (HE) sections], cumulus cell morphology and follicle diameter could be used routinely to classify freshly retrieved follicles. Finally, we applied a mechanical, minimally invasive, follicle isolation protocol and extended it to three ruminant species, yielding viable preantral follicles without compromising further in vitro processing and allowing routine follicle characterization upon retrieval.
A case of neonatal myocardial infarction: left coronary artery thrombus resolution and normalisation of ventricular function by intracoronary low-dose tissue plasminogen activator
Authors: Hallbergson Anna , Gillespie Matthew J. , Dori Yoav
Published: July 2014

Neonatal myocardial infarction is a rare clinical entity that is associated with high mortality. Reported treatment strategies include supportive care, extracorporeal membrane oxygenation, thrombolytics, and surgical thrombectomy. Herein we report a neonate who developed an acute myocardial infarction owing to a thrombus in the proximal left coronary artery. At 24 hours of life, he was treated with local (intracoronary) thrombolytic therapy at a lower dose than previously reported, as well as with systemic anticoagulation. There was subsequent angiographic resolution of the thrombus and normalisation of left ventricular function.
MARKET INTERNALIZATION OF EXTERNALITIES: WHAT IS FAILING?
Authors: Berta Nathalie , Bertrand Elodie
Published: July 2014

The usual internalization of externality ‘by the market’ can be thought of through two different exchange modes: competitive markets, with Kenneth J. Arrow (1969); or bargaining, with Ronald H. Coase (1960). Although, in both cases, ‘externality’ refers to a non-exchanged effect that produces suboptimalities, these authors are working with two different, implicit conceptions of externality, rooted in different analytical worlds and calling for different institutions—parametric prices for the former but not for the latter. Moreover, while both start out with different theoretical frameworks, the authors share a concern for realism and unite when they introduce transaction costs, both advocating a policy design that calls for taking into account the costs of the different solutions. Nevertheless, this introduction of transaction costs does not itself escape consistency problems, since they do both maintain a reference to their respective ideal worlds.
The AMINO experiment: RNA stability under solar radiation studied on the EXPOSE-R facility of the International Space Station
Authors: Vergne Jacques , Cottin Hervé , da Silva Laura , Brack André , Chaput Didier , Maurel Marie-Christine
Published: July 2014

Careful examination of the present metabolism and in vitro selection of various catalytic RNAs strongly support the RNA world hypothesis as a crucial step of the origins and early life evolution. Small functional RNAs were exposed from 10 March 2009 to 21 January 2011 to space conditions on board the International Space Station in the EXPOSE-R mission. The aim of this study was to investigate the preservation or modification properties such as integrity of RNAs after space exposition. The exposition to the solar radiation has a strong degradation effect on the size distribution of RNA. Moreover, the comparison between the in-flight samples, exposed to the Sun and not exposed, indicates that the solar radiation degrades RNA bases.
Abortion Politics and the Decline of the Separation of Church and State: The Southern Baptist Case
Authors: Lewis Andrew R.
Published: July 2014

Between the late 1970s and early 1990s, the Southern Baptist Convention (SBC) altered its First Amendment advocacy, shifting from being an ardent supporter of the strict separation of church and state to being a champion of the government accommodation of religion. At the same time, the denomination also became unswervingly pro-life. In this article, I use the SBC case to identify a previously under-analyzed link between abortion politics and church-state politics. I suggest that pro-life politics played an important role in the SBC's shift away from the separation of church and state. I focus on three areas where abortion politics aided this shift: (1) opposing separationists’ assertions that anti-abortion policies violated the Establishment Clause; (2) becoming allies rather than foes with Catholics; and (3) promoting a greater emphasis on the free exercise of religion. I conclude by discussing the implications for the relationship between religion, law, and politics.
Impact of temperature, feeding preference and vaccination on Schmallenberg virus transmission in Scotland
Authors: Bessell Paul R. , Auty Harriet K. , Searle Kate R. , Handel Ian G. , Purse Bethan V. , de C. Bronsvoort B. Mark
Published: July 2014

First identified in 2011, Schmallenberg virus (SBV) is principally transmitted by Culicoides midges and affects ruminants. Clinical presentation is typified by foetal abnormalities, but despite very high infection rates, relatively few animals present with clinical signs. In this paper we further develop a previously published stochastic mathematical model of SBV spread to investigate the optimal deployment of a vaccine for SBV in Scotland, a country that has experienced only sporadic and isolated cases of SBV. We consider the use of the vaccine under different temperatures and explore the effects of a vector preference for feeding on cattle. We demonstrate that vaccine impact is optimised by targeting it at the high risk areas in the south of Scotland, or vaccinating only cattle. At higher than average temperatures and hence increased transmission potential, the relative impact of vaccination is considerably enhanced. Vaccine impact is also enhanced if vectors feed preferentially on cattle. These findings are of considerable importance when planning control strategies for SBV and also have important implications for management of other arboviruses such as Bluetongue virus. Environmental determinants and feeding preferences should be researched further to inform development of effective control strategies.
Bio-specific and bio-orthogonal chemistries to switch-off the quencher of a FRET-based fluorescent probe: application to living-cell biothiol imaging
Authors: Egloff C. , Jacques S. A. , Nothisen M. , Weltin D. , Calligaro C. , Mosser M. , Remy J.-S. , Wagner A.
Published: July 2014

A quencher sensitive to both a biological metabolite (biothiols) and a bio-orthogonal reagent (dithionite) was developed.
Sulfur gradient-distributed CNF composite: a self-inhibiting cathode for binder-free lithium–sulfur batteries
Authors: Fu Kun , Li Yanpeng , Dirican Mahmut , Chen Chen , Lu Yao , Zhu Jiadeng , Li Yao , Cao Linyou , Bradford Philip D. , Zhang Xiangwu
Published: July 2014

A novel sulfur gradient cathode was developed with a high specific capacity and improved cycling stability for Li–S batteries.
Flavin-catalyzed aerobic oxidation of sulfides and thiols with formic acid/triethylamine
Authors: Murahashi Shun-Ichi , Zhang Dazhi , Iida Hiroki , Miyawaki Toshio , Uenaka Masaaki , Murano Kenji , Meguro Kanji
Published: July 2014

An efficient and practical method for flavin-catalyzed aerobic oxidation of sulfides and thiols with formic acid/TEA is described.
Crystals for sustainability – structuring Al-based MOFs for the allocation of heat and cold
Authors: de Lange M. F. , Ottevanger C. P. , Wiegman M. , Vlugt T. J. H. , Gascon J. , Kapteijn F.
Published: July 2014

The special water adsorption behaviour of CAU-10-H makes it ideal for application in adsorption driven heat pumps and chillers.
CO oxidation catalyzed by Pt-embedded graphene: a first-principles investigation
Authors: Liu Xin , Sui Yanhui , Duan Ting , Meng Changong , Han Yu
Published: July 2014

The combination of reactive Pt atoms and defects over graphene makes Pt-embedded graphene a superior catalyst for low-temperature CO oxidation.
Hydrothermal synthesis of octahedra-based layered niobium oxide and its catalytic activity as a solid acid
Authors: Murayama Toru , Chen Junli , Hirata Jun , Matsumoto Keeko , Ueda Wataru
Published: July 2014

Layered-structure-type niobium oxides were synthesized by the hydrothermal method by using ammonium niobium oxalate as a precursor.
Mixed-ligand ruthenium polypyridyl complexes as apoptosis inducers in cancer cells, the cellular translocation and the important role of ROS-mediated signaling
Authors: Zhao Zhennan , Luo Zuandi , Wu Qiong , Zheng Wenjie , Feng Yanxian , Chen Tianfeng
Published: July 2014

Ruthenium complexes enter cancer cells through TfR-mediated endocytosis and translocate to the mitochondria, where they activate ROS-mediated apoptosis.
Photocatalytic organic pollutants degradation in metal–organic frameworks
Authors: Wang Chong-Chen , Li Jian-Rong , Lv Xiu-Liang , Zhang Yan-Qiu , Guo Guangsheng
Published: July 2014

This review summarizes research advances in photocatalytic organic pollutant degradation in metal–organic frameworks.
Influence of electrotaxis on cell behaviour
Authors: Cortese Barbara , Palamà Ilaria Elena , D'Amone Stefania , Gigli Giuseppe
Published: July 2014

Understanding the mechanism of cell migration and interaction with the microenvironment is not only of critical significance to the function and biology of cells, but also has extreme relevance and impact on physiological processes and diseases such as morphogenesis, wound healing, neuron guidance, and cancer metastasis.
Cross-catalytic peptide nucleic acid (PNA) replication based on templated ligation
Authors: Singhal Abhishek , Nielsen Peter E.
Published: July 2014

PNA replication via decameric template directed cross-catalytic ligation follows product inhibited kinetics yielding approximately two replication rounds.
One-pot synthesis of unsymmetrical diarylacetylenes via Sonogashira/deacetonation/Sonogashira cross-coupling of two different aryl chlorides with 2-methyl-3-butyn-2-ol
Authors: Xu Kai , Sun Suyan , Zhang Guodong , Yang Fan , Wu Yangjie
Published: July 2014

Synthesis of unsymmetrical diarylacetylenes via one-pot Sonogashira/Deacetonation/Sonogashira cross-coupling of two different aryl chlorides with 2-methyl-3-butyn-2-ol was developed.
Highly selective naphthalimide-based fluorescent probe for direct hydrogen sulfide detection in the environment
Authors: Guo Yuanyuan , Zeng Tao , Shi Guoqing , Cai Yaqi , Xie Ruliang
Published: July 2014

Here, we report a highly selective and sensitive approach for monitoring hydrogen sulfide (H2S) in the environment through an ingenious naphthalimide-based fluorescent probe.
Synthesis and properties of a new second-order NLO chromophore containing the benzo[b]furan moiety for electro-optical materials
Authors: Zhang Maolin , Deng Guowei , Zhang Airui , Xu Huajun , Huang Heyan , Peng Chengcheng , Bo Shuhui , Liu Xinhou , Zhen Zhen , Qiu Ling
Published: July 2014

We have designed and synthesized a new chromophore having a 1,1,7,7-tetramethyljulolidine fused furan ring as the electron donor group to systematically investigate the role of the benzo[b]furan ring in NLO chromophores.
Selective pyridine recognition by an imidazole dicarboxylate-based 3D cadmium(ii) MOF
Authors: Yue Zhifang , Chen Zhenna , Yao Minjie , Wang Haili , Li Gang
Published: July 2014

One newly prepared 3D polymer (1) composed of left- and right-handed helices containing [Cd8(p-ClPhHIDC)12(4,4′-bipy)6] cages shows selective pyridine recognition, with a visual colour change from pearl to pink under ultraviolet irradiation.
Polyaniline nanofibers–graphene oxide nanoplatelets composite thin film electrodes for electrochemical capacitors
Authors: Khalid Mohd. , Tumelero Milton A. , Zoldan Vinicius C. , Pla Cid Cristiani C. , Franceschini Dante F. , Timm Ronaldo A. , Kubota Lauro T. , Moshkalev Stanislav A. , Pasa Andre A.
Published: July 2014

A facile electrochemical method was applied to synthesize graphene oxide nanoplatelets and polyaniline nanofiber composite thin film electrodes for supercapacitors.
Lasting and self-healing superhydrophobic surfaces by coating of polystyrene/SiO2 nanoparticles and polydimethylsiloxane
Authors: Xue Chao-Hua , Zhang Zhi-Dong , Zhang Jing , Jia Shun-Tian
Published: July 2014

By spraying polystyrene/SiO2 nanoparticles as a coating skeleton and polydimethylsiloxane as a hydrophobic interconnection, lasting and self-healing superhydrophobic surfaces were fabricated.
Magnetic field-assisted electroless anodization: TiO2 nanotube growth on discontinuous, patterned Ti films
Authors: Mohammadpour Arash , Shankar Karthik
Published: July 2014

A magnetic field-assisted anodization process that transforms Ti thin films on arbitrary substrates into TiO2 nanotube arrays without an applied voltage or current.
Photochemical synthesis of pyrene perfluoroalkyl derivatives and their embedding in a polymethylmethacrylate matrix: a spectroscopic and structural study
Authors: Pibiri I. , Buscemi S. , Palumbo Piccionello A. , Saladino M. L. , Chillura Martino D. , Caponetti E.
Published: July 2014

A photochemical approach to perfluoroalkyl derivatives of pyrene embedded in a PMMA matrix to obtain materials for optoelectronic applications.
Surface modification with MK-2 organic dye in a ZnO/P3HT hybrid solar cell: Impact on device performance
Authors: Kim Yu Jin , An Tae Kyu , Oh Seung-Jeong , Chung Dae Sung , Park Chan Eon
Published: July 2014

The photovoltaic performance of a hybrid ZnO/P3HT heterojunction was improved by modifying the device surface with the MK-2 dye. This organic dye enhanced the compatibility between the polymer and the metal oxide, increased the exciton separation efficiency, and improved the molecular ordering in the charge transport network. The resulting device displayed a substantial enhancement in the photocurrent, open circuit voltage, and fill factor, leading to a 12-fold increase in the power conversion efficiency relative to the unmodified device, from 0.13% to 1.53%.
Kinetic neoclassical transport in the H-mode pedestal
Authors: Battaglia D. J. , Burrell K. H. , Chang C. S. , Ku S. , deGrassie J. S. , Grierson B. A.
Published: July 2014

Multi-species kinetic neoclassical transport through the QH-mode pedestal and scrape-off layer on DIII-D is calculated using XGC0, a 5D full-f particle-in-cell drift-kinetic solver with self-consistent neutral recycling and sheath potentials. Quantitative agreement between the flux-driven simulation and the experimental electron density, impurity density, and orthogonal measurements of impurity temperature and flow profiles is achieved by adding random-walk particle diffusion to the guiding-center drift motion. The radial electric field (Er) that maintains ambipolar transport across flux surfaces and to the wall is computed self-consistently on closed and open magnetic field lines and is in excellent agreement with experiment. The Er inside the separatrix is the unique solution that balances the outward flux of thermal tail deuterium ions against the outward neoclassical electron flux and inward pinch of impurity and colder deuterium ions. Particle transport in the pedestal is primarily due to anomalous transport, while the ion heat and momentum transport are primarily due to the neoclassical transport. The full-f treatment quantifies the non-Maxwellian energy distributions that describe a number of experimental observations in low-collisionallity pedestals on DIII-D, including intrinsic co-Ip parallel flows in the pedestal, ion temperature anisotropy, and large impurity temperatures in the scrape-off layer.
Computer simulation study of surface wave dynamics at the crystal-melt interface
Authors: Benet Jorge , MacDowell Luis G. , Sanz Eduardo
Published: July 2014

We study, by means of computer simulations, the crystal-melt interface of three different systems: hard-spheres, Lennard Jones, and the TIP4P/2005 water model. In particular, we focus on the dynamics of surface waves. We observe that the processes involved in the relaxation of surface waves are characterized by distinct time scales: a slow one related to the continuous recrystallization and melting, that is governed by capillary forces; and a fast one which we suggest to be due to a combination of processes that quickly cause small perturbations to the shape of the interface (e.g., Rayleigh waves, subdiffusion, or attachment/detachment of particles to/from the crystal). The relaxation of surface waves becomes dominated by the slow process as the wavelength increases. Moreover, we see that the slow relaxation is not influenced by the details of the microscopic dynamics. In a time scale characteristic for the diffusion of the liquid phase, the relaxation dynamics of the crystal-melt interface of water is around one order of magnitude slower than that of Lennard Jones or hard spheres, which we ascribe to the presence of orientational degrees of freedom in the water molecule. Finally, we estimate the rate of crystal growth from our analysis of the capillary wave dynamics and compare it with previous simulation studies and with experiments for the case of water.
Nanoparticle dispersion in superfluid helium
Authors: Meichle David P. , Lathrop Daniel P.
Published: July 2014

Cryogenic fluid flows including liquid nitrogen and superfluid helium are a rich environment for novel scientific discovery. Flows can be measured optically and dynamically when faithful tracer particles are dispersed in the liquid. We present a reliable technique for dispersing commercially available fluorescent nanoparticles into cryogenic fluids using ultrasound. Five types of fluorescent nanoparticles ranging in size from 5 nm to 1 μm were imaged in liquid nitrogen and superfluid helium, and were tracked at frame rates up to 100 Hz.
Initial implementation of a Thomson scattering diagnostic for Proto-MPEX
Authors: Biewer T. M. , Shaw G.
Published: July 2014

Internal funds have been used at Oak Ridge National Laboratory to enable the initial installation of a laser based, Thomson scattering (TS) diagnostic on the prototype Material-Plasma Exposure eXperiment (Proto-MPEX). Since the funds are limited in amount and duration, the initial TS system has followed a low cost design and rapid implementation. This paper will discuss the design elements of the initial TS configuration on Proto-MPEX and issues encountered during installation. Avenues of response to system limitations will be discussed, along with considerations for further optimization. The laser system will undergo reconfiguration to enable additional project milestones, e.g., laser induced break-down spectroscopy.
Probing interfacial dynamics and mechanics using submerged particle microrheology. I. Theory
Authors: Shlomovitz Roie , Evans Arthur A. , Boatwright Thomas , Dennin Michael , Levine Alex J.
Published: July 2014

Microrheology relies on tracking the thermal or driven motion of microscopic particles in a soft material. It is well suited to the study of materials that have no three-dimensional realization, which makes them difficult to study using a macroscopic rheometer. For this reason, microrheology is becoming an important rheological probe of Langmuir monolayers and membranes. Interfacial microrheology, however, has been difficult to reconcile quantitatively with more traditional macroscopic approaches. We suggest that uncertainties in accounting for the mechanical coupling of the tracer particle to the interface or membrane are responsible for these discrepancies. To resolve them, we propose a new non-contact approach to interfacial microrheology that uses particles submerged in the subphase a known distance below the interface. In this first of two papers, we present calculations of the response function (and thus the equilibrium fluctuation spectrum) of a spherical particle submerged below a viscoelastic surface that has a finite surface tension and/or bending modulus. In the second paper, we compare these results to submerged particle microrheology in a few example systems, showing quantitative agreement.
Can xenon in water inhibit ice growth? Molecular dynamics of phase transitions in water–Xe system
Authors: Artyukhov Vasilii I. , Pulver Alexander Yu. , Peregudov Alex , Artyuhov Igor
Published: July 2014

Motivated by recent experiments showing the promise of noble gases as cryoprotectants, we perform molecular dynamics modeling of phase transitions in water with xenon under cooling. We follow the structure and dynamics of xenon water solution as a function of temperature. Homogeneous nucleation of clathrate hydrate phase is observed and characterized. As the temperature is further reduced we observe hints of dissociation of clathrate due to stronger hydrophobic hydration, pointing towards a possible instability of clathrate at cryogenic temperatures and conversion to an amorphous phase comprised of “xenon + hydration shell” Xe·(H2O)21.5 clusters. Simulations of ice–xenon solution interface in equilibrium and during ice growth reveal the effects of xenon on the ice–liquid interface, where adsorbed xenon causes roughening of ice surface but does not preferentially form clathrate. These results provide evidence against the ice-blocker mechanism of xenon cryoprotection.
Controlling ion fluxes during reactive sputter-deposition of SnO2:F
Authors: Jäger Timo , Romanyuk Yaroslav E. , Tiwari Ayodhya N. , Anders André
Published: July 2014

Magnetron sputtering of fluorine-doped tin oxide (FTO) is a scalable deposition method for large-area transparent conducting films used in fenestration, photovoltaics, and other applications. The electrical conductivity of sputtered FTO is, however, lower than that of spray-pyrolized FTO because of the ion damage induced by high energy ions leading to a reduction of the crystal quality in sputtered FTO films. In this study, various ion species present during the reactive sputtering of a metallic tin target in a mixed Ar/O2/CF4 atmosphere are systematically characterized by energy and mass spectrometry, and possible ways of controlling the ion fluxes are explored. Ion energy distribution functions (IEDFs) of the negative ions F− and O− exhibit large peaks at an energy corresponding to the full target voltage. Although the applied partial pressure of CF4 is about 1/30 than that of O2, the obtained IEDFs of F− and O− have comparable peak height, which can be attributed to a higher electronegativity of F. The IEDFs of positively charged O+, O2+, Ar+, and Sn+ species have their peaks around 2–8 eV. To control ion fluxes a solenoid or permanent magnets were placed between the target and the mass spectrometer. The flux of positive ions could be varied by several orders of magnitude as a function of the applied current through the solenoid, whereas the high-energy (>100 eV) negative F− and O− ions were not notably deflected. By using permanent magnets with the B-field orthogonal to the ion trajectory, the flux of O− ions could be decreased by two orders and the exposure to the high-energy F− ions was completely suppressed.
Local current density measurement using a Rogowski probe in Tokyo Spherical Tokamak-2
Authors: Furui H. , Nagashima Y. , Takase Y. , Ejiri A. , Kakuda H. , Sonehara M. , Oosako T. , Tsujii N. , Hiratsuka J. , Imamura K. , Inada T. , Nakamura K. , Nakanishi A. , Shinya T. , Togashi H. , Tsuda S. , Wakatsuki T. , Yamaguchi T.
Published: July 2014

A Rogowski probe consisting of a small multi-layer Rogowski coil, five magnetic pick-up coils, and a Langmuir probe was developed to measure the local current density and its direction. It can be moved along the major radius and can be turned around its axis. This probe was used to measure the current density profile near the last closed flux surface of Ohmic plasmas in Tokyo Spherical Tokamak-2. The current density profile was measured successfully with a signal to noise ratio of greater than 20.
The broadband microwave spectra of the monoterpenoids thymol and carvacrol: Conformational landscape and internal dynamics
Authors: Schmitz D. , Shubert V. A. , Giuliano B. M. , Schnell M.
Published: July 2014

The rotational spectra of the monoterpenoids thymol and carvacrol are reported in the frequency range 2–8.5 GHz, obtained with broadband Fourier-transform microwave spectroscopy. For carvacrol four different conformations were identified in the cold conditions of the molecular jet, whereas only three conformations were observed for thymol. The rotational constants and other molecular parameters are reported and compared with quantum chemical calculations. For both molecules, line splittings due to methyl group internal rotation were observed and the resulting barrier heights could be determined. The experimental barrier heights, 4.0863(25) kJ/mol for trans-carvacrol-A, 4.4024(16) kJ/mol for trans-carvacrol-B, and 0.3699(11) kJ/mol for trans-thymol-A, are compared with similar molecules.
Bag breakup of low viscosity drops in the presence of a continuous air jet
Authors: Kulkarni V. , Sojka P. E.
Published: July 2014

This work examines the breakup of a single drop of various low viscosity fluids as it deforms in the presence of continuous horizontal air jet. Such a fragmentation typically occurs after the bulk liquid has disintegrated upon exiting the atomizer and is in the form of an ensemble of drops which undergo further breakup. The drop deformation and its eventual disintegration is important in evaluating the efficacy of a particular industrial process, be it combustion in automobile engines or pesticide spraying in agricultural applications. The interplay between competing influences of surface tension and aerodynamic disruptive forces is represented by the Weber number, We, and Ohnesorge number, Oh, and used to describe the breakup morphology. The breakup pattern considered in our study corresponds to that of a bag attached to a toroidal ring which occurs from ∼12 < We < ∼16. We aim to address several issues connected with this breakup process and their dependence on We and Oh which have been hitherto unexplored. The We boundary at which breakup begins is theoretically determined and the expression obtained, $We = 12( {1 + {\raise0.7ex\hbox{2} \!\mathord{\left/ {\vphantom {2 3}}\right.\kern-\nulldelimiterspace}\!\lower0.7ex\hbox{3}}Oh^2 } )$We=12(1+2/3Oh2), is found to match well with experimental data {[L.-P. Hsiang and G. M. Faeth, Int. J. Multiphase Flow 21(4), 545–560 (1995)] and [R. S. Brodkey, “Formation of drops and bubbles,” in The Phenomena of Fluid Motions (Addison-Wesley, Reading, 1967)]}. An exponential growth in the radial extent of the deformed drop and the streamline dimension of the bag is predicted by a theoretical model and confirmed by experimental findings. These quantities are observed to strongly depend on We. However, their dependence on Oh is weak.
Rapid calculation method for Frenkel-type two-exciton states in one to three dimensions
Authors: Ajiki Hiroshi
Published: July 2014

Biexciton and two-exciton dissociated states of Frenkel-type excitons are well described by a tight-binding model with a nearest-neighbor approximation. Such two-exciton states in a finite-size lattice are usually calculated by numerical diagonalization of the Hamiltonian, which requires an increasing amount of computational time and memory as the lattice size increases. I develop here a rapid, memory-saving method to calculate the energies and wave functions of two-exciton states by employing a bisection method. In addition, an attractive interaction between two excitons in the tight-binding model can be obtained directly so that the biexciton energy agrees with the observed energy, without the need for the trial-and-error procedure implemented in the numerical diagonalization method.
High spatial resolution upgrade of the electron cyclotron emission radiometer for the DIII-D tokamak
Authors: Truong D. D. , Austin M. E.
Published: July 2014

The 40-channel DIII-D electron cyclotron emission (ECE) radiometer provides measurements of Te(r,t) at the tokamak midplane from optically thick, second harmonic X-mode emission over a frequency range of 83–130 GHz. The frequency spacing of the radiometer's channels results in a spatial resolution of ∼1–3 cm, depending on local magnetic field and electron temperature. A new high resolution subsystem has been added to the DIII-D ECE radiometer to make sub-centimeter (0.6–0.8 cm) resolution Te measurements. The high resolution subsystem branches off from the regular channels’ IF bands and consists of a microwave switch to toggle between IF bands, a switched filter bank for frequency selectivity, an adjustable local oscillator and mixer for further frequency down-conversion, and a set of eight microwave filters in the 2–4 GHz range. Higher spatial resolution is achieved through the use of a narrower (200 MHz) filter bandwidth and closer spacing between the filters’ center frequencies (250 MHz). This configuration allows for full coverage of the 83–130 GHz frequency range in 2 GHz bands. Depending on the local magnetic field, this translates into a “zoomed-in” analysis of a ∼2–4 cm radial region. Expected uses of these channels include mapping the spatial dependence of Alfven eigenmodes, geodesic acoustic modes, and externally applied magnetic perturbations. Initial Te measurements, which demonstrate that the desired resolution is achieved, are presented.
Parallax diagnostics of radiation source geometric dilution for iron opacity experiments
Authors: Nagayama T. , Bailey J. E. , Loisel G. , Rochau G. A. , Falcon R. E.
Published: July 2014

Experimental tests are in progress to evaluate the accuracy of the modeled iron opacity at solar interior conditions [J. E. Bailey et al., Phys. Plasmas 16, 058101 (2009)]. The iron sample is placed on top of the Sandia National Laboratories z-pinch dynamic hohlraum (ZPDH) radiation source. The samples are heated to 150–200 eV electron temperatures and 7× 1021–4× 1022 cm−3 electron densities by the ZPDH radiation and backlit at its stagnation [T. Nagayama et al., Phys. Plasmas 21, 056502 (2014)]. The backlighter attenuated by the heated sample plasma is measured by four spectrometers along ±9° with respect to the z-pinch axis to infer the sample iron opacity. Here, we describe measurements of the source-to-sample distance that exploit the parallax of spectrometers that view the half-moon-shaped sample from ±9°. The measured sample temperature decreases with increased source-to-sample distance. This distance must be taken into account for understanding the sample heating.
Impact of microstructure on the effective diffusivity in random packings of hard spheres
Authors: Liasneuski H. , Hlushkou D. , Khirevich S. , Höltzel A. , Tallarek U. , Torquato S.
Published: July 2014

We present results of computer simulations of the effective diffusion coefficient in bulk random packings of hard monosized spheres with solid volume fraction between 0.54 (random-loose packing) and 0.634 (maximally random jammed). Six types of sphere packings were generated with different protocols and parameters resulting in a systematically varied degree of microstructural heterogeneity. The packing morphology is qualitatively characterized by statistical analyses of Voronoi cells obtained from spatial tessellation of the packing space. Diffusive transport of point-like tracers in the pore space of the packings was simulated with a random-walking particle-tracking technique. Our results indicate that the effective transport characteristics of the random sphere packings are not fully defined from the solid volume fraction but also depend on the packing microstructure. For the first time, we compared (i) the values of the effective diffusion coefficient Deff simulated in packings with different morphologies, and (ii) the corresponding values of Deff obtained from an approximate analytical formula involving the three-point microstructural parameter ζ2. This analysis reveals that this approximation involving ζ2 clearly reflects key morphological specificity of individual sphere packings and provides a sufficiently accurate estimate of the effective diffusion coefficient.
Study on electrical characteristics of barrier-free atmospheric air diffuse discharge generated by nanosecond pulses and long wire electrodes
Authors: Li Lee , Liu Yun-Long , Teng Yun , Liu Lun , Pan Yuan
Published: July 2014

In room-temperature atmospheric air, the large-scale diffuse plasmas can be generated via high-voltage nanosecond pulses with short rise-time and wire electrodes. Diffuse discharge with the wire electrode length up to 110.0 cm and the discharge spacing of several centimeters has been investigated in this paper. Electrical characteristics of diffuse discharge have been analyzed by their optical photographs and measuring of the voltage and current waveforms. Experimental results show the electrode spacing, and the length of wire electrodes can influence the intensity and mode transition of diffuse discharge. The characteristic of current waveforms is that there are several current oscillation peaks at the time of applied pulsed voltage peak, and at the tail of applied pulse, the conduction current component will compensate the displacement one so that the measured current is unidirectional in diffuse discharge mode. The transition from diffuse discharge to arc discharge is always with the increasing of conduction current density. As for nanosecond pulses with long tail, the long wire electrodes are help for generating non-equilibrium diffuse plasmas.