bluuebunny/crossref_metadata_2025 huggingface dataset:
First description of milk flow traits in Tunisian dairy dromedary camels under an intensive farming system
Authors: Atigui Moufida , Hammadi Mohamed , Barmat Ahmed , Farhat Mohamed , Khorchani Touhami , Marnet Pierre-Guy
Published: March 2014

In order to evaluate milking ability in dromedary camels, 124 milk flow curves were registered during morning milking of 20 dairy Maghrebi dromedary camels. Animals were in lactations 1–8, were 6–19 years old and were 4–15 months of their current lactation. Milk flow curves were recorded using an electronic milk flow meter (Lactocorder®). Milk flow curves were classified in three typical patterns: type 1 represents curves with one high and short peak of milk flow; type 2 represents curves with a moderate mean milk flow rate during a large plateau phase; and type 3 represents curves with lower mean milk flow rate and a relatively longer milking duration. The ratio of the different milk flow patterns in the population evaluated was 40:38:22% for types 1, 2 and 3, respectively. The highest milk yield per milking, average and peak milk flow were observed in camels with type 1 curves (4·24 kg, 1·49 and 3·54 kg/min, respectively) followed by type 2 animals (3·30 kg, 1·12 and 2·12 kg/min, respectively) and lastly type 3 curves (2·34 kg, 0·65 and 1·23 kg/min, respectively). This study confirmed that a major proportion of dromedary camels have a suitable machine milking ability. Nevertheless, our results suggest that pre-stimulation and improving the milking process may improve milking efficiency and guarantee a more complete and rapid emptying of the udder.
The League of Nations Controversy among British Protestants
Authors: RUOTSILA MARKKU
Published: March 2014

Traditionally, the British reaction to the League of Nations has been narrated in terms of an almost uniform acceptance. British Churches, in particular, have been seen as among its most enthusiastic supporters and principal campaigners for its creation. In fact, a significant amount of debate over the League erupted in the Church of England and the Free Churches. In these debates, Christian Socialists emerged as passionate League enthusiasts and conservative premillenarians as equally passionate opponents. Throughout, many of the key church leaders who were publicly supportive of the League continued to harbour deep private reservations.
A redescription of Lobatostoma kemostoma (MacCallum & MacCallum, 1913) (Trematoda: Aspidogastrea) from the florida pompano fish Trachinotus carolinus (Linnaeus, 1766) off the Brazilian coast
Authors: Alves P.V. , Borges J.N. , Santos C.P. , Luque J.L.
Published: March 2014

A redescription of the aspidogastrean trematode Lobatostoma kemostoma (MacCallum & MacCallum, 1913) is provided based on examination of type material, voucher specimens available at institutional collections and newly collected specimens from the type host, Trachinotus carolinus (Linnaeus, 1766), off the Angra dos Reis, Brazil. Partial sequence of its 28S rDNA is given. Lobatostoma kemostoma can be distinguished from the other eight species of the genus by: (1) the hindbody being longer than the ventral disc; and (2) the cephalic lobes having the same shape and size. Features observed for the first time include the number and detailed arrangement of alveoli on the ventral disc, the terminal genitalia and the ovarian complex. New illustrations and morphometric data are given. In the present survey the host specificity in the genus, the validity of some morphological features and the occurrence of an Indian species of Lobatostoma from off the Brazilian coast are discussed. A lectotype of L. kemostoma from the type series deposited at United States National Parasite Collection is also designated.
Pulmonary function in patients with chronic rhinosinusitis and allergic rhinitis
Authors: Kariya S , Okano M , Oto T , Higaki T , Makihara S , Haruna T , Nishizaki K
Published: March 2014

Background:

A close relationship between upper and lower respiratory tract diseases has been reported. However, little is known about pulmonary function in patients with upper respiratory tract diseases.

Methods:

Pulmonary function was measured in: 68 patients with chronic rhinosinusitis without nasal polyps, 135 patients with chronic rhinosinusitis with nasal polyps, 89 patients with allergic rhinitis and 100 normal control subjects. The relationships between pulmonary function and clinical parameters were assessed. These parameters included radiographic severity of chronic rhinosinusitis, serum total immunoglobulin E levels, concentrations of cytokines in nasal secretions and exhaled nitric oxide levels.

Results:

The pulmonary function of patients with chronic rhinosinusitis was significantly affected. The level of interleukin-5 in nasal secretions was significantly correlated with pulmonary function in patients with chronic rhinosinusitis.

Conclusion:

The findings indicated latent obstructive lung function changes in chronic rhinosinusitis patients. The cytokines in nasal secretions might be related to obstructive lung function changes in chronic rhinosinusitis.
Hilbert's program relativized; Proof-theoretical and foundational reductions
Authors: Feferman Solomon
Published: March 2014

In the Symposium on Hilbert's Program to which the following was contributed, I was asked to talk about the metamathematical aspects of Hilbert's Program (H.P.), while the other two speakers (Simpson and Prawitz) were to deal with the mathematical and philosophical aspects respectively. However, more so than for other foundational schemes, these three aspects of H.P., both as originally conceived and in its subsequent developments, are intimately linked.

Here I shall survey a body of proof-theoretical results stemming from H.P., but organized in a way that is closely tied to various reductive foundational aims, albeit going beyond those advanced by Hilbert. I believe this view of reductive proof-theory (not original with me) helps one to better understand what has been achieved thereby than other, more familiar accounts.
Uniqueness, definability and interpolation
Authors: Došen Kosta , Schroeder-Heister Peter
Published: March 2014

This paper is meant to be a comment on Beth's definability theorem. In it we shall make the following points.

Implicit definability as mentioned in Beth's theorem for first-order logic is a special case of a more general notion of uniqueness. If α is a nonlogical constant, Tα a set of sentences, α* an additional constant of the same syntactical category as α and Tα, a copy of Tα with α* instead of α, then for implicit definability of α in Tα one has, in the case of predicate constants, to derive α(x1,…,xn) ↔ α*(x1,…,xn) from Tα ∪ Tα*, and similarly for constants of other syntactical categories. For uniqueness one considers sets of schemata Sα and derivability from instances of Sα ∪ Sα* in the language with both α and α*, thus allowing mixing of α and α* not only in logical axioms and rules, but also in nonlogical assumptions. In the first case, but not necessarily in the second one, explicit definability follows. It is crucial for Beth's theorem that mixing of α and α* is allowed only inside logic, not outside. This topic will be treated in §1.

Let the structural part of logic be understood roughly in the sense of Gentzen-style proof theory, i.e. as comprising only those rules which do not specifically involve logical constants. If we restrict mixing of α and α* to the structural part of logic which we shall specify precisely, we obtain a different notion of implicit definability for which we can demonstrate a general definability theorem, where a is not confined to the syntactical categories of nonlogical expressions of first-order logic. This definability theorem is a consequence of an equally general interpolation theorem. This topic will be treated in §§2, 3, and 4.
-sets of reals
Authors: Ihoda Jaime I.
Published: March 2014

We prove that the only implications between four notions for -sets of reals are
Seminormal λ-generated ideals on Pκλ
Authors: Johnson C. A.
Published: March 2014

In this paper we consider the problem of lifting properties of the Fréchet ideal Iκ = {X ⊆ κ: ∣X∣ < κ} on a regular uncountable cardinal κ, to an analogue about Iκλ, the ideal of not unbounded subsets of Pκλ. With this in mind, in §1 we introduce and study the class of seminormal λ-generated ideals on Pκλ. We shall see that ideals belonging to this class display properties which are clearly analogous to those of the Fréchet ideal on κ (for instance, with regard to saturation, normality and weak selectivity) and yet are closely related to Iκλ. Our results here show that if λ<λ = λ, then many restrictions of Iκλ are weakly selective, nowhere precipitous and, quite suprisingly, seminormal (but nowhere normal). These latter two results suggest the question of whether any restriction of Iκλ can ever be normal. In §2 we prove that if κ is strongly inaccessible, λ<κ = 2λ and NSκλ, the ideal of nonstationary subsets of Pκλ, has a mild selective property, then NSκλ∣A = Iκλ∣A for some stationary A ⊆ Pκλ.

In [1] Baumgartner showed that if κ is weakly compact and P is the collection of indescribable subsets of κ, then P → (P, κ)2. As a Pκλ analogue of indescribability, Carr (see [3]–[5]) introduced the λ-Shelah property, but was unable to derive the natural Pκλ analogue of Baumgartner's result, (where NShκλ is the normal ideal on Pκλ induced by the λ-Shelah property). In §3 we show that the problem lies in the fact that, as far as we know, NShκλ is not sufficiently distributive, and derive conditions which are sufficient and, in a sense, necessary to yield partitions related to .
A downward Löwenheim-Skolem theorem for infinitary theories which have the unsuperstability property
Authors: Grossberg Rami
Published: March 2014

We present a downward Löwenheim-Skolem theorem which transfers downward formulas from L∞,ω to , ω. The simplest instance is:

Theorem 1. Let λ > κ be infinite cardinals, and let L be a similarity type of cardinality κ at most. For every L-structure M of cardinality λ and every X ⊆ M there exists a model N ≺ M containing the set X of power ∣X∣ · κ such that for every pair of finite sequences a, b ∈ N

The following theorem is an application:

Theorem 2. Let λ<κ, T ∈ , ω, and suppose χ is a Ramsey cardinal greater than λ. If T has the (χ, , ω)-unsuperstability property, then T has the (χ, , ω)-unsuperstability property.
On ultracoproducts of compact hausdorff spaces
Authors: Gurevič R.
Published: March 2014

I present solutions to several questions of Paul Bankston [2] by means of another version of the ultracoproduct construction, and explain the relation of ultracoproduct of compact Hausdorff spaces to other constructions combining topology, algebra and logic.
ω1-like recursively saturated models of Presburger's arithmetic
Authors: Harnik Victor
Published: March 2014

Let Pr be Presburger's arithmetic, i.e., the complete theory of the structure (ω, +). Lipshitz and Nadel showed in [4] that a countable model of Pr is recursively saturated iff it can be expanded to a model of Peano arithmetic, PA. As a starting point for an introductory discussion, let us mention one more fact about countable recursively saturated models of Pr. If is such a model then the following is readily seen (as explained also in §1):

Any two countable recursively saturated elementary endextensions of are isomorphic.

If we drop “countable” from the assumption of this statement, we can still say that the two models are ∞ω-equivalent. Must they be isomorphic if both have cardinality ℵ1? Certainly not, since one of the models can be ω1-like while the other is not. Once we realized this much, let us concentrate on ω1-like structures. We prove in §3:

Theorem. Any countable recursively saturated modelof Pr hasisomorphism types of ω1-like recursively saturated elementary endextensions. Only one of these is the isomorphism type of a structure that can be expanded to a model of PA.

The key technical result is proven in §2. It says that an as above has precisely two countable recursively saturated elementary endextensions which are nonisomorphic over .
Types of simple α-recursively enumerable sets
Authors: Lerman Manuel
Published: March 2014

Let α be an admissible ordinal, and let (α) denote the lattice of α-r.e. sets, ordered by set inclusion. An α-r.e. set A is α*-finite if it is α-finite and has ordertype less than α* (the Σ1 projectum of α). An a-r.e. set S is simple if (the complement of S) is not α*-finite, but all the α-r.e. subsets of are α*-finite. Fixing a first-order language ℒ suitable for lattice theory (see [2, §1] for such a language), and noting that the α*-finite sets are exactly those elements of (α), all of whose α-r.e. subsets have complements in (α) (see [4, p. 356]), we see that the class of simple α-r.e. sets is definable in ℒ over (α). In [4, §6, (Q22)], we asked whether an admissible ordinal α exists for which all simple α-r.e. sets have the same 1-type. We were particularly interested in this question for α = ℵ1L (L is Gödel's universe of constructible sets). We will show that for all α which are regular cardinals of L (ℵ1L is, of course, such an α), there are simple α-r.e. sets with different 1-types.

The sentence exhibited which differentiates between simple α-r.e. sets is not the first one which comes to mind. Using α = ω for intuition, one would expect any of the sentences “S is a maximal α-r.e. set”, “S is an r-maximal α-r.e. set”, or “S is a hyperhypersimple α-r.e. set” to differentiate between simple α-r.e. sets. However, if α > ω is a regular cardinal of L, there are no maximal, r-maximal, or hyperhypersimple α-r.e. sets (see [4, Theorem 4.11], [5, Theorem 5.1] and [1,Theorem 5.21] respectively). But another theorem of (ω) points the way.
Prefatory statement to the index volume
Authors: Church Alonzo
Published: March 2014

Volume 26 of the Journal will appear in two parts, of which this is Part 1, and will be devoted entirely to indexes covering Volumes 1–25. This part contains an Index of contributed papers, by authors (including problems); an Index of abstracts, by authors; an Index of reviews by authors (i.e., by authors of the works reviewed); and an Index of reviewers. It is planned to devote Part 2 to an Index of reviews by subjects — which, unlike the other indexes of reviews, will cover also the material in A bibliography of symbolic logic — and to a Chronological index of reviews, designed to supply in brief summary the actual bibliographical references for items which are reviewed or listed in the review sections of Volumes 1–25.
Effects of livestock on occurrence of the Vulnerable red panda Ailurus fulgens in Rara National Park, Nepal
Authors: Sharma Hari P. , Belant Jerrold L. , Swenson Jon E.
Published: March 2014

The Vulnerable red panda Ailurus fulgens is endemic to the Himalayas. Anthropogenic activities, including deforestation, have degraded the species’ habitat but the effects of livestock have not been examined. We assessed the effects of illegal livestock activity on the presence of the red panda in Rara National Park, Nepal. The probability of detecting red panda faecal pellets decreased with livestock occurrence but not with elevation or aspect. The presence of bamboo and proximity to water are important to red pandas but did not influence their habitat use at the spatial resolution evaluated. Livestock grazing in Rara National Park appears to adversely affect the presence of the red panda within its habitat. To reduce illegal livestock grazing we recommend enforcement of existing regulations, that training workshops be held for herders, and awareness-raising and dialogue with residents.
Influences of foreign accent on preschoolers’ word recognition and story comprehension
Authors: BARKER BRITTAN A. , TURNER LINDSAY MEYER
Published: March 2014

To better understand how talker-specific information influences spoken language processing in different experimental listening tasks, we examined the effect of a foreign accent on preschoolers’ word recognition and story comprehension. In Experiment 1, preschoolers listening to words presented by a native-accented talker recognized significantly more words than did preschoolers listening to words presented by a foreign-accented talker. In Experiment 2, preschoolers listening to a story narrated by a native-accented talker demonstrated significantly lower comprehension accuracy compared to preschoolers listening to a foreign-accented narrator. These findings underscore the importance of the experimental task when examining and making claims about the influence of accent information on young children's spoken language processing.
A combustion wave of permanent form in a compressible gas
Authors: Forbes Lawrence K. , Derrick William
Published: March 2014

A model is presented for describing the propagation of a one-dimensional wave of permanent form in a compressible gas in a pipe. Energy is lost to the system through the walls of the pipe, but the combustion wave produces heat through an exothermic chemical reaction. The full set of equations for the model is reduced to a phase-plane system, and it is shown that, for small amplitude waves, a weakly non-linear analysis leads to a temperature profile that is a classical solitary wave. A novel shooting method is developed for the full non-linear problem, and this confirms and extends the solitary-wave solution, up to a value of the temperature amplitude at which the wave begins to develop a shock. The jump conditions across the shock are presented, and numerical integration is used to continue the solution for temperature amplitudes at which a shock is present. An example is given of the extreme situation in which the shock is so strong that all the fuel behind the shock is exhausted.
Opening end-of-life discussions: How to introduce Voicing My CHOiCES™, an advance care planning guide for adolescents and young adults
Authors: Zadeh Sima , Pao Maryland , Wiener Lori
Published: March 2014

Objective:

Each year, more than 11,000 adolescents and young adults (AYAs), aged 15–34, die from cancer and other life-threatening conditions. In order to facilitate the transition from curative to end-of-life (EoL) care, it is recommended that EoL discussions be routine, begin close to the time of diagnosis, and continue throughout the illness trajectory. However, due largely to discomfort with the topic of EoL and how to approach the conversation, healthcare providers have largely avoided these discussions.

Method:

We conducted a two-phase study through the National Cancer Institute with AYAs living with cancer or pediatric HIV to assess AYA interest in EoL planning and to determine in which aspects of EoL planning AYAs wanted to participate. These results provided insight regarding what EoL concepts were important to AYAs, as well as preferences in terms of content, design, format, and style. The findings from this research led to the development of an age-appropriate advance care planning guide, Voicing My CHOiCES™.

Results:

Voicing My CHOiCES™: An Advanced Care Planning Guide for AYAbecame available in November 2012. This manuscript provides guidelines on how to introduce and utilize an advance care planning guide for AYAs and discusses potential barriers.

Significance of Results:

Successful use of Voicing My CHOiCES™ will depend on the comfort and skills of the healthcare provider. The present paper is intended to introduce the guide to providers who may utilize it as a resource in their practice, including physicians, nurses, social workers, chaplains, psychiatrists, and psychologists. We suggest guidelines on how to: incorporate EoL planning into the practice setting, identify timepoints at which a patient's goals of care are discussed, and address how to empower the patient and incorporate the family in EoL planning. Recommendations for introducing Voicing My CHOiCES™ and on how to work through each section alongside the patient are provided.
Digitale Demenz? Mythen und wissenschaftliche Befundlage zur Auswirkung von Internetnutzung
Authors: Appel Markus , Schreiner Constanze
Published: March 2014

Digitale Medien sind, so selbstverständlich wie nie zuvor, Teil unseres Alltags. Damit verbunden sind Befürchtungen, dass vor allem die intensive Computer- und Internetnutzung negative Konsequenzen aufweist. Der vorliegende Beitrag gibt einen Überblick zum Forschungsstand über die Auswirkungen der Nutzung von Computer und Internet. Neun populäre Mythen werden identifiziert und mit Hilfe einer Zusammenschau von meta-analytischen Befunden auf deren wissenschaftlichen Gehalt überprüft. Im Mittel der aggregierten Ergebnisse finden sich keine Belege dafür, dass die Nutzung digitaler Medien zu sozialem Rückzug führt, gesellschaftlich-politisches Engagement verhindert oder die selbstberichtete Einsamkeit erhöht. Die Zusammenhänge zwischen Internetnutzung und Wohlbefinden bzw. Depressivität sind sehr klein, aber signifikant, wie auch die Zusammenhänge zwischen der Nutzung von Bildschirmmedien und Übergewicht. Im Mittel zeigt sich ferner, dass das Lernen mit Computer und Internet, inklusive Lernspiele, positive Konsequenzen haben kann. Allerdings sind die negativen Auswirkungen von gewalthaltigen Videospielen auf aggressives Verhalten und Erleben ebenfalls gut belegt. Die Befunde werden mit Blick auf populärwissenschaftliche Publikationen sowie die Rolle der Psychologie diskutiert.
Classification and quantification of bacteriophage taxa in human gut metagenomes
Authors: Waller Alison S , Yamada Takuji , Kristensen David M , Kultima Jens Roat , Sunagawa Shinichi , Koonin Eugene V , Bork Peer
Published: March 2014

Bacteriophages have key roles in microbial communities, to a large extent shaping the taxonomic and functional composition of the microbiome, but data on the connections between phage diversity and the composition of communities are scarce. Using taxon-specific marker genes, we identified and monitored 20 viral taxa in 252 human gut metagenomic samples, mostly at the level of genera. On average, five phage taxa were identified in each sample, with up to three of these being highly abundant. The abundances of most phage taxa vary by up to four orders of magnitude between the samples, and several taxa that are highly abundant in some samples are absent in others. Significant correlations exist between the abundances of some phage taxa and human host metadata: for example, ‘Group 936 lactococcal phages’ are more prevalent and abundant in Danish samples than in samples from Spain or the United States of America. Quantification of phages that exist as integrated prophages revealed that the abundance profiles of prophages are highly individual-specific and remain unique to an individual over a 1-year time period, and prediction of prophage lysis across the samples identified hundreds of prophages that are apparently active in the gut and vary across the samples, in terms of presence and lytic state. Finally, a prophage–host network of the human gut was established and includes numerous novel host–phage associations.
Counter-ion Dependent, Longitudinal Unzipping of Multi-Walled Carbon Nanotubes to Highly Conductive and Transparent Graphene Nanoribbons
Authors: Shinde Dhanraj B. , Majumder Mainak , Pillai Vijayamohanan K.
Published: March 2014

Here we report for the first time, a simple hydrothermal approach for the bulk production of highly conductive and transparent graphene nanoribbons (GNRs) using several counter ions from K2SO4, KNO3, KOH and H2SO4 in aqueous media, where, selective intercalation followed by exfoliation gives highly conducting GNRs with over 80% yield. In these experiments, sulfate and nitrate ions act as a co-intercalant along with potassium ions resulting into exfoliation of multi-walled carbon nanotubes (MWCNTs) in an effective manner. The striking similarity of experimental results in KOH and H2SO4 that demonstrates partially damaged MWCNTs, implies that no individual K+, SO42− ion plays a key role in unwrapping of MWCNTs, rather this process is largely effective in the presence of both cations and anions working in a cooperative manner. The GNRs can be used for preparing conductive 16 kΩsq−1, transparent (82%) and flexible thin films using low cost fabrication method.
A high-throughput device for size based separation of C. elegans developmental stages
Authors: Ai Xiaoni , Zhuo Weipeng , Liang Qionglin , McGrath Patrick T. , Lu Hang
Published: March 2014

We present an efficient and fast device for size-based separation ofCaenorhabditis elegans.
MIROR: a method for cell-type specific microRNA occupancy rate prediction
Authors: Xie Peng , Liu Yu , Li Yanda , Zhang Michael Q. , Wang Xiaowo
Published: March 2014

This work provides a novel method to quantitatively predict miRNA–mRNA interactions in a specific cell type.
A facile procedure to fabricate nano calcium carbonate–polymer-based superhydrophobic surfaces
Authors: Tang Xinde , Yu Faqi , Guo Wenjuan , Wang Tieshi , Zhang Qun , Zhu Qiangqiang , Zhang Xiao , Pei Meishan
Published: March 2014

A facile procedure to fabricate superhydrophobic surfaces based on nano calcium carbonate–polymer composites has been described.
Hierarchical porous Co3O4 nanosheet arrays directly grown on carbon cloth by an electrochemical route for high performance Li-ion batteries
Authors: Cheng Chao , Zhou Gang , Du Jun , Zhang Haiming , Guo Di , Li Qiuhong , Wei Weifeng , Chen Libao
Published: March 2014

Co3O4 nanosheet arrays were grown on carbon cloth homogeneously; excellent electrochemical performance was obtained due to the unique structure and morphology.
Enhancing the electrochromic response of polyaniline films by the preparation of hybrid materials based on polyaniline, chitosan and organically modified clay
Authors: Silva Rosanny C. , Sarmento Marina V. , Nogueira Fred A. R. , Tonholo Josealdo , Mortimer Roger J. , Faez Roselena , Ribeiro Adriana S.
Published: March 2014

Electrochromic materials based on PAni, chitosan and clay show distinct colour variation depending on the compound present in the hybrid material.
Palladium-catalyzed Suzuki reaction in aqueous solvents applied to unprotected nucleosides and nucleotides
Authors: Hervé Gwénaëlle , Sartori Guillaume , Enderlin Gérald , Mackenzie Grahame , Len Christophe
Published: March 2014

Nucleoside analogues have attracted much attention due to their potential biological activities.
Nitrogen doped graphene: influence of precursors and conditions of the synthesis
Authors: Wang Lu , Sofer Zdeněk , Luxa Jan , Pumera Martin
Published: March 2014

The level of nitrogen doping of graphene strongly depends on the type of the starting graphite oxide and temperature used.
Simultaneous detection of roxithromycin and dopamine using a sensor platform based on poly(sulfosalicylic acid) and its application in human serum studies
Authors: Zhang Xin , Gu Shuqing , Ding Yaping
Published: March 2014

An electrochemical sensor based on poly(sulfosalicylic acid) was fabricated for individual and simultaneous determination of roxithromycin and dopamine with a sensitive detection limit and a satisfactory detection result using human serum samples.
Kinetic study of glucose oxidase on microfluidic toner-based analytical devices for clinical diagnostics with image-based detection
Authors: Oliveira Karoliny Almeida , Medrado e Silva Paula Beatriz , de Souza Fabrício Ribeiro , Martins Felipe Terra , Coltro Wendell Karlos Tomazelli
Published: March 2014

This report describes a kinetic study for the glucose oxidase reaction on microfluidic toner-based analytical devices based on digital image analysis.
Exploiting lanthanide luminescence in supramolecular assemblies
Authors: Lehr Joshua , Beer Paul D. , Faulkner Stephen , Davis Jason J.
Published: March 2014

We review herein significant and recent work focused on the incorporation of luminescent lanthanides into switchable, supramolecular and surface bound assemblies.
A nitro-decorated NbO-type metal–organic framework with a highly selective CO2 uptake and CH4 storage capacity
Authors: Zhang Mingxing , Wang Qian , Lu Zhiyong , Liu Huiyan , Liu Wenlong , Bai Junfeng
Published: March 2014

A nitro-decorated and highly porous metal–organic framework with NbO topology was reported, exhibiting good adsorption selectivity of CO2/CH4 (8) and CO2/N2 (24) at 273 K and 1 bar, high methane total uptake of 184 cm3 cm−3 at 290 K and 35 bar.
A simple and efficient synthetic route for preparation of NaYF4 upconversion nanoparticles by thermo-decomposition of rare-earth oleates
Authors: Liu Xiaodong , Zhang Xiao , Tian Gan , Yin Wenyan , Yan Liang , Ruan Longfei , Yang Zhiyong , Xiao Debao , Gu Zhanjun
Published: March 2014

A two-step synthetic route for fabrication of hexagonal-phase NaYF4 and NaYF4-based nano-phosphors based on thermal decomposition of their corresponding oleate precursors is provided and systematically investigated.
Wet chemical synthesis of intermetallic Pt3Zn nanocrystals via weak reduction reaction together with UPD process and their excellent electrocatalytic performances
Authors: Chen Qiaoli , Zhang Jiawei , Jia Yanyan , Jiang Zhiyuan , Xie Zhaoxiong , Zheng Lansun
Published: March 2014

Intermetallic Pt3Zn nanocrystals were synthesized via weak reduction reaction together with an underpotential deposition process.
Europium- and lithium-doped yttrium oxide nanocrystals that provide a linear emissive response with X-ray radiation exposure
Authors: Stanton Ian N. , Belley Matthew D. , Nguyen Giao , Rodrigues Anna , Li Yifan , Kirsch David G. , Yoshizumi Terry T. , Therien Michael J.
Published: March 2014

[Y2−xO3; Eux, Liy] nanocrystals display scintillation responses that correlate linearly with incident radiation exposure at X-ray excitation energies ranging from 40–220 kVp, and thus can serve as sensing elements for next-generation radiation dosimeters designed for diagnostic and therapeutic applications.
Facile microwave-assisted synthesis and effective photocatalytic hydrogen generation of Zn2GeO4 with different morphology
Authors: Yang Min , Ji Ying , Liu Wei , Wang Ying , Liu Xiaoyang
Published: March 2014

Single-crystalline hexagonal prism Zn2GeO4 nanorods and hierarchical Zn2GeO4 microspheres have been successfully synthesized via a facile microwave-assisted solution-phase approach.
Modular polymerized ionic liquid block copolymer membranes for CO2/N2 separation
Authors: Adzima Brian J. , Venna Surendar R. , Klara Steven S. , He Hongkun , Zhong Mingjiang , Luebke David R. , Mauter Meagan S. , Matyjaszewski Krzysztof , Nulwala Hunaid B.
Published: March 2014

A robust and orthogonal approach to access modular block-copolymer poly(ionic liquid)s.
Development and Preliminary Evaluation of a Pediatric Spanish–English Speech Perception Task
Authors: Calandruccio Lauren , Gomez Bianca , Buss Emily , Leibold Lori J.
Published: March 2014

Purpose

The purpose of this study was to develop a task to evaluate children's English and Spanish speech perception abilities in either noise or competing speech maskers.

Method

Eight bilingual Spanish–English and 8 age-matched monolingual English children (ages 4.9–16.4 years) were tested. A forced-choice, picture-pointing paradigm was selected for adaptively estimating masked speech reception thresholds. Speech stimuli were spoken by simultaneous bilingual Spanish–English talkers. The target stimuli were 30 disyllabic English and Spanish words, familiar to 5-year-olds and easily illustrated. Competing stimuli included either 2-talker English or 2-talker Spanish speech (corresponding to target language) and spectrally matched noise.

Results

For both groups of children, regardless of test language, performance was significantly worse for the 2-talker than for the noise masker condition. No difference in performance was found between bilingual and monolingual children. Bilingual children performed significantly better in English than in Spanish in competing speech. For all listening conditions, performance improved with increasing age.

Conclusions

Results indicated that the stimuli and task were appropriate for speech recognition testing in both languages, providing a more conventional measure of speech-in-noise perception as well as a measure of complex listening. Further research is needed to determine performance for Spanish-dominant listeners and to evaluate the feasibility of implementation into routine clinical use.
Spectroscopic accuracy directly from quantum chemistry: Application to ground and excited states of beryllium dimer
Authors: Sharma Sandeep , Yanai Takeshi , Booth George H. , Umrigar C. J. , Chan Garnet Kin-Lic
Published: March 2014

We combine explicit correlation via the canonical transcorrelation approach with the density matrix renormalization group and initiator full configuration interaction quantum Monte Carlo methods to compute a near-exact beryllium dimer curve, without the use of composite methods. In particular, our direct density matrix renormalization group calculations produce a well-depth of De = 931.2 cm−1 which agrees very well with recent experimentally derived estimates De = 929.7±2 cm−1 [J. M. Merritt, V. E. Bondybey, and M. C. Heaven, Science 324, 1548 (2009)] and De= 934.6 cm−1 [K. Patkowski, V. Špirko, and K. Szalewicz, Science 326, 1382 (2009)], as well the best composite theoretical estimates, De = 938±15 cm−1 [K. Patkowski, R. Podeszwa, and K. Szalewicz, J. Phys. Chem. A 111, 12822 (2007)] and De=935.1±10 cm−1 [J. Koput, Phys. Chem. Chem. Phys. 13, 20311 (2011)]. Our results suggest possible inaccuracies in the functional form of the potential used at shorter bond lengths to fit the experimental data [J. M. Merritt, V. E. Bondybey, and M. C. Heaven, Science 324, 1548 (2009)]. With the density matrix renormalization group we also compute near-exact vertical excitation energies at the equilibrium geometry. These provide non-trivial benchmarks for quantum chemical methods for excited states, and illustrate the surprisingly large error that remains for 1 \documentclass[12pt]{minimal}\begin{document}$^1\Sigma ^-_g$\end{document}Σg−1 state with approximate multi-reference configuration interaction and equation-of-motion coupled cluster methods. Overall, we demonstrate that explicitly correlated density matrix renormalization group and initiator full configuration interaction quantum Monte Carlo methods allow us to fully converge to the basis set and correlation limit of the non-relativistic Schrödinger equation in small molecules.
Exciton dissociation in the presence of phonons: A reduced hierarchy equations of motion approach
Authors: Yao Yao , Yang Wenchao , Zhao Yang
Published: March 2014

Combining the reduced hierarchy equations of motion (HEOM) approach with the Wigner-function formalism, we investigate nonperturbatively exciton dissociation under the influence of a phonon bath in an organic heterojunction. The exciton is modeled by an electron-hole pair with the electron moving in the presence of both an external electric field and the Coulomb attraction potential from the hole. In the absence of a phonon bath, calculated HEOM results reproduce those from the Onsager-Braun theory in weak electric fields. In the presence of a phonon bath, substantial deviations from the Onsager-Braun theory are found, signaling phonon-induced quantum effects. Furthermore, time evolution of the spatial current distribution is examined, and an initial spike followed by a polarity change of the transient photocurrent have been recovered.
Rovibronic structure in slow photoelectron velocity-map imaging spectroscopy of CH2CN− and CD2CN−
Authors: Weichman Marissa L. , Kim Jongjin B. , Neumark Daniel M.
Published: March 2014

We report high-resolution anion photoelectron spectra of the cryogenically cooled cyanomethide anion, CH2CN−, and its isotopologue, CD2CN−, using slow photoelectron velocity-map imaging (SEVI) spectroscopy. Electron affinities of 12 468(2) cm−1 for CH2CN and 12 402(2) cm−1 for CD2CN are obtained, demonstrating greater precision than previous experiments. New vibrational structure is resolved for both neutral species, especially activity of the ν5 hydrogen umbrella modes. The ν6 out-of-plane bending mode fundamental frequency is measured for the first time in both systems and found to be 420(10) cm−1 for CH2CN and 389(8) cm−1 for CD2CN. Some rotational structure is resolved, allowing for accurate extraction of vibrational frequencies. Temperature-dependent SEVI spectra show marked effects ascribed to controlled population of low-lying anion vibrational levels. We directly measure the inversion splitting between the first two vibrational levels of the anion ν5 umbrella mode in both species, finding a splitting of 130(20) cm−1 for CH2CN− and 81(20) cm−1 for CD2CN−. Franck-Condon forbidden activity is observed and attributed to mode-specific vibrational autodetachment from the CH2CN− and CD2CN− dipole bound excited states. We also refine the binding energy of the anion dipole bound states to 39 and 42 cm−1, respectively, for CH2CN− and CD2CN−.
The one-electron oxidation of a dithiolate molecule: The importance of chemical intuition
Authors: Bushnell Eric A. C. , Burns Thomas D. , Boyd Russell J.
Published: March 2014

A series of nine commonly used density functional methods were assessed to accurately predict the oxidation potential of the (C2H2S2−2/C2H2S2•−) redox couple. It was found that due to their greater tendency for charge delocalization the GGA functionals predict a structure where the radical electron is delocalized within the alkene backbone of C2H2S2•−, whereas the hybrid functionals and the reference QCISD/cc-pVTZ predict that the radical electron remains localized on the sulfurs. However, chemical intuition suggests that the results obtained with the GGA functionals should be correct. Indeed, with the use of the geometries obtained at the HCTH/6-311++G(3df,3pd) level of theory both the QCISD and hybrid DFT methods yield a molecule with a delocalized electron. Notably, this new molecule lies at least 53 kJ mol−1 lower in energy than the previously optimized one that had a localized radical. Using these new structures the calculated oxidation potential was found to be 2.71–2.97 V for the nine DFT functionals tested. The M06-L functional provided the best agreement with the QCISD/cc-pVTZ reference oxidation potential of 3.28 V.
Evaluation of model exchange-correlation kernels in the adiabatic connection fluctuation-dissipation theorem for inhomogeneous systems
Authors: Lu Deyu
Published: March 2014

We investigated the effect of the exchange-correlation kernels of Dobson and Wang (DW) [Phys. Rev. B 62, 10038 (2000)] and Corradini, Del Sole, Onida, and Palummo (CDOP) [Phys. Rev. B 57, 14569 (1998)] in the framework of the adiabatic connection fluctuation-dissipation theorem. The original CDOP kernel was generalized to treat inhomogeneous systems, and an efficient numerical implementation was developed. We found that both kernels improve the correlation energy in bulk silicon as compared to that evaluated from the random phase approximation (RPA). In particular, the correlation energy from the CDOP kernel is in excellent agreement with the diffusion Monte Carlo result. In the case of the Kr dimer, while the DW kernel leads to stronger binding than RPA, the CDOP kernel does the opposite. The cause of this quite different behavior of the two kernels is discussed. Our study suggests that special attention needs to be paid to describe the effective interaction at the low density regions when developing model exchange-correlation kernels.
Contribution of the entropy on the thermodynamic equilibrium of vacancies in nickel
Authors: Metsue Arnaud , Oudriss Abdelali , Bouhattate Jamaa , Feaugas Xavier
Published: March 2014

The equilibrium vacancy concentration in nickel was determined from ab initio calculations performed with both generalized gradient approximation and local density approximation up to the melting point. We focus the study on the vacancy formation entropy expressed as a sum of a vibration and an electronic contribution, which were determined from the vibration modes and the electronic densities of states. Applying a method based on the quasi-harmonic approximation, the temperature dependence of the defect formation energy and entropy were calculated. We show that the vibrations of the first shell of atoms around the defect are predominant to the vibration formation entropy. On the other hand, the electronic formation entropy is very sensitive to the exchange-correlation potential used for the calculations. Finally, the vacancy concentration is computed at finite temperature with the calculated values for the defect formation energy and entropy. In order to reconcile point-defects concentration obtained with our calculations and experimental data, we conducted complementary calorimetric measurements of the vacancy concentration in the 1073–1273 K temperature range. Close agreement between theory and experiments at high temperature is achieved if the calculations are performed with the generalized gradient approximation and both vibration and electronic contributions to the formation entropy are taken into account.
Stimulated Brillouin scattering reduction induced by self-focusing for a single laser speckle interacting with an expanding plasma
Authors: Masson-Laborde P. E. , Hüller S. , Pesme D. , Labaune Ch. , Depierreux S. , Loiseau P. , Bandulet H.
Published: March 2014

The origin of the low level of stimulated Brillouin scattering (SBS) observed in laser-plasma experiments carried out with a single laser speckle is investigated by means of three-dimensional simulations and modeling in the limit when the laser beam power P is well above the critical power for ponderomotive self-focusing We find that the order of magnitude of the time averaged reflectivities, together with the temporal and spatial SBS localization observed in our simulations, are correctly reproduced by our modeling. It is observed that, after a short transient stage, SBS reaches a significant level only (i) as long as the incident laser pulse is increasing in amplitude and (ii) in a single self-focused speckle located in the low-density front part of the plasma. In order to describe self-focusing in an inhomogeneous expanding plasma, we have derived a new Lagrangian density describing this process. Using then a variational approach, our model reproduces the position and the peak intensity of the self-focusing hot spot in the front part of the plasma density profile as well as the local density depletion in this hot spot. The knowledge of these parameters then makes it possible to estimate the spatial amplification of SBS as a function of the laser beam power and consequently to explain the experimentally observed SBS reflectivity, considerably reduced with respect to standard theory in the regime of large laser beam power.
Study on the polymer diffusion in a media with periodically distributed nano-sized fillers
Authors: Li Chao-Yang , Qian Chang-Ji , Yang Qing-Hui , Luo Meng-Bo
Published: March 2014

The effect of nano-sized fillers on the equilibrium and dynamical properties of a linear polymer is studied by using off-lattice Monte Carlo simulation. Fillers are arranged periodically in the system with period d and Lennard-Jones interaction between polymer and fillers is considered. Results show that the statistical dimension and dynamical diffusion of the polymer are dependent on the polymer-filler interaction strength ɛpf and the relative size between RG0 and d, here RG0 is the radius of gyration of polymer in dilute solution. Normal diffusion of polymer is always observed in the regime 2RG0 > d. And the diffusion coefficient D is scaled with chain length N as D ∼ N −α, where the exponent α increases with ɛpf. Whereas in the regime 2RG0 < d ≪ Nl0 with l0 the mean bond length of polymer, normal diffusion is observed only at ɛpf < 2, but the polymer will be adsorbed on the fillers and cannot diffuse at ɛpf > 2. In addition, we find that there is a critical interaction strength ɛ*pf = 2 in our model system.
A quasi-classical mapping approach to vibrationally coupled electron transport in molecular junctions
Authors: Li Bin , Wilner Eli Y. , Thoss Michael , Rabani Eran , Miller William H.
Published: March 2014

We develop a classical mapping approach suitable to describe vibrationally coupled charge transport in molecular junctions based on the Cartesian mapping for many-electron systems [B. Li and W. H. Miller, J. Chem. Phys. 137, 154107 (2012)]. To properly describe vibrational quantum effects in the transport characteristics, we introduce a simple transformation rewriting the Hamiltonian in terms of occupation numbers and use a binning function to facilitate quantization. The approach provides accurate results for the nonequilibrium Holstein model for a range of bias voltages, vibrational frequencies, and temperatures. It also captures the hallmarks of vibrational quantum effects apparent in step-like structure in the current-voltage characteristics at low temperatures as well as the phenomenon of Franck-Condon blockade.
Magnetic properties of Co-Zr-B magnets produced by spark plasma sintering method
Authors: Saito Tetsuji , Akiyama Tomoya
Published: March 2014

Magnets of Co-Zr-B, one of the permanent magnetic compounds without rare-earth elements, were successfully produced by the spark plasma sintering method. The resultant Co-Zr-B magnets had high densities of 92%–96% and consisted mainly of the CoxZr (x ≈ 5) phase. The coercivity of the Co-Zr-B magnets was highly dependent on the consolidation temperature and the boron content. The highest maximum energy product of 6.0 MGOe, with a remanence of 6.4 kG and the coercivity of 4.0 kOe, was achieved by the Co80Zr18B2 magnets consolidated at 873 K.
Structural and electrical characterizations of InxGa1-xAs/InP structures for infrared photodetector applications
Authors: Asar Tarık , Özçelik Süleyman , Özbay Ekmel
Published: March 2014

Three InGaAs/InP structures for photodetector applications were grown with different indium compositions by MBE technique. The structural properties of the samples have been obtained by means of high resolution X-ray diffraction and secondary ion mass spectrometry measurements. Three InGaAs/InP metal-semiconductor-metal devices were fabricated at room temperature. The experimental forward and reverse bias current–voltage characteristics of the devices such as ideality factor, barrier height, and saturation current were evaluated considering the structural properties of the grown structures. The carrier recombination lifetime and diffusion length in the devices were also calculated using carrier density and mobility data obtained with Hall effect measurement at room temperature. It was determined that all room temperature fabricated devices improved the Schottky barrier height. Especially, the device fabricated on the lower mismatched structure exhibited barrier height enhancement from 0.2 eV, which is the conventional barrier height to 0.642 eV. In addition, the obtained results show that the room temperature fabricated devices on InGaAs/InP structures can be convenient for infrared photodetector applications.