bluuebunny/crossref_metadata_2025 huggingface dataset:
Vaccination of sheep and cattle against haemonchosis
Authors: Bassetto C.C. , Amarante A.F.T.
Published: April 2015

Vaccines against gastrointestinal nematodes are one potential option for the control of parasitic gastroenteritis in ruminants. Excretory/secretory (E/S) and hidden antigens are being studied as candidates for vaccines against Haemonchus spp., which is a major parasite in cattle and small ruminants that are raised in warm climates. Protection has been observed after vaccination with some E/S proteases, particularly cysteine proteases and with some glycans that are abundant on the surfaces and in the secretory products of helminths. However, the most promising results are being obtained with glycoprotein antigens extracted from the microvillar surfaces of the Haemonchus contortus intestinal cells. These antigens are called ‘hidden′ because they are not exposed to the host's immune system during infection. Thus far, recombinant forms of these antigens have not been usefully protective. However, because only 5 μg of antigen is required per dose, production of a native antigen vaccine from adult parasites has been found to be practical and commercially viable. Trials indicate that a vaccine made from one particular isolate will cross-protect against geographically distant isolates.
A comparison of sequence and length polymorphism for genotypingCryptosporidiumisolates
Authors: WIDMER G. , CACCIÒ S. M.
Published: April 2015

Simple sequence repeat markers have played an important role in elucidating the epidemiology of human and animal cryptosporidiosis. The drawback of sequence length polymorphisms is that nucleotide substitutions remain undetected. As some laboratories have opted for using length polymorphisms, while others have relied on sequencing, there is a need to compare both methods. We used a diversified set of unique length polymorphisms and matching nucleotide sequences to assess the ability of each genotyping protocol to discern clusters of relatedCryptosporidium parvumisolates. We found a weak correlation between the two distance measures for individual markers. This analysis was extended to four-locus genotypes based on sequence length data or concatenated sequences from the same loci. We interrogated these data to assess whether one would reach the same conclusions regardless of the genotyping method. Clusters of isolates generated with the concatenated sequences were not observed with amplicon length, indicating that inferences on the structure of aCryptosporidiumpopulation depend on the genotyping method. Moreover, isolate clusters derived from concatenated sequences were dependent on the algorithm used to calculate distances. These results emphasize the need for harmonizing genotyping tools, not only by selecting informative markers, but also by standardizing the entire genotyping method.
Trade Reform and Institution Building: Peru and Argentina under the WTO
Authors: BARACAT ELÍAS A. , FINGER J. MICHAEL , THORNE RAÚL LEÓN , NOGUÉS JULIO J.
Published: April 2015

Beyond removing restrictions, trade reform in Latin American in the 1980s and 1990s was in significant part an attempt to change the domestic politics of trade and to reformulate the culture of policy management by introducing procedural characteristics that WTO trade remedy rules advance. This paper examines how trade reform in Peru and Argentina has gone since the reforms of the 1990s. Peru provides a valuable example of sustaining reforms. Leaders have used negotiations and other international instruments to disseminate among Peruvians a positive vision of Peru in the international economy, and to extend the application of WTO-based governance principles. Peru has introduced few new restrictions and all of them have been through WTO-sanctioned policy instruments. Argentina, on the other hand, has introduced multiple restrictions, through procedures that eschew WTO governance principles. Moreover, leaders there have returned trade politics to thedependenciaphilosophy that sees the international economy as an exploitive environment.The paper brings out the weakness of international obligations to limit Argentina's return to import substitution and the pains at which Peru has gone to maintain the management of its economy within the same rules that Argentina has so easily violated. To have commercial value, the GATT/WTO principle that members applyonlyapproved methods of trade control must have operational expression innationalinstitutions.
Visualization of electrochemically driven solid-state phase transformations using operando hard X-ray spectro-imaging
Authors: Li Linsen , Chen-Wiegart Yu-chen Karen , Wang Jiajun , Gao Peng , Ding Qi , Yu Young-Sang , Wang Feng , Cabana Jordi , Wang Jun , Jin Song
Published: April 2015

In situ techniques with high temporal, spatial and chemical resolution are key to understand ubiquitous solid-state phase transformations, which are crucial to many technological applications. Hard X-ray spectro-imaging can visualize electrochemically driven phase transformations but demands considerably large samples with strong absorption signal so far. Here we show a conceptually new data analysis method to enable operando visualization of mechanistically relevant weakly absorbing samples at the nanoscale and study electrochemical reaction dynamics of iron fluoride, a promising high-capacity conversion cathode material. In two specially designed samples with distinctive microstructure and porosity, we observe homogeneous phase transformations during both discharge and charge, faster and more complete Li-storage occurring in porous polycrystalline iron fluoride, and further, incomplete charge reaction following a pathway different from conventional belief. These mechanistic insights provide guidelines for designing better conversion cathode materials to realize the promise of high-capacity lithium-ion batteries.
Epigenomic evolution in diffuse large B-cell lymphomas
Authors: Pan Heng , Jiang Yanwen , Boi Michela , Tabbò Fabrizio , Redmond David , Nie Kui , Ladetto Marco , Chiappella Annalisa , Cerchietti Leandro , Shaknovich Rita , Melnick Ari M. , Inghirami Giorgio G. , Tam Wayne , Elemento Olivier
Published: April 2015

The contribution of epigenomic alterations to tumour progression and relapse is not well characterized. Here we characterize an association between disease progression and DNA methylation in diffuse large B-cell lymphoma (DLBCL). By profiling genome-wide DNA methylation at single-base pair resolution in thirteen DLBCL diagnosis–relapse sample pairs, we show that DLBCL patients exhibit heterogeneous evolution of tumour methylomes during relapse. We identify differentially methylated regulatory elements and determine a relapse-associated methylation signature converging on key pathways such as transforming growth factor-β (TGF-β) receptor activity. We also observe decreased intra-tumour methylation heterogeneity from diagnosis to relapsed tumour samples. Relapse-free patients display lower intra-tumour methylation heterogeneity at diagnosis compared with relapsed patients in an independent validation cohort. Furthermore, intra-tumour methylation heterogeneity is predictive of time to relapse. Therefore, we propose that epigenomic heterogeneity may support or drive the relapse phenotype and can be used to predict DLBCL relapse.
Prediction of recurrence-free survival using a protein expression-based risk classifier for head and neck cancer
Authors: Chauhan S S , Kaur J , Kumar M , Matta A , Srivastava G , Alyass A , Assi J , Leong I , MacMillan C , Witterick I , Colgan T J , Shukla N K , Thakar A , Sharma M C , Siu K W M , Walfish P G , Ralhan R
Published: April 2015

Loco-regional recurrence in 50% of oral squamous cell carcinoma (OSCC) patients poses major challenge for oncologists. Lack of biomarkers that can predict disease aggressiveness and recurrence risk makes the scenario more dismal. On the basis of our earlier global proteomic analyses we identified five differentially expressed proteins in OSCC. This study aimed to develop protein biomarkers-based prognostic risk prediction model for OSCC. Sub-cellular expression of five proteins, S100A7, heterogeneous nuclear ribonucleoproteinK (hnRNPK), prothymosin α (PTMA), 14-3-3ζ and 14-3-3σ was analyzed by immunohistochemistry in test set (282 Indian OSCCs and 209 normal tissues), correlated with clinic–pathological parameters and clinical outcome over 12 years to develop a risk model for prediction of recurrence-free survival. This risk classifier was externally validated in 135 Canadian OSCC and 96 normal tissues. Biomarker signature score based on PTMA, S100A7 and hnRNPK was associated with recurrence free survival of OSCC patients (hazard ratio=1.11; 95% confidence interval 1.08, 1.13, P<0.001, optimism-corrected c-statistic=0.69) independent of clinical parameters. Biomarker signature score stratified OSCC patients into high- and low-risk groups with significant difference for disease recurrence. The high-risk group had median survival 14 months, and 3-year survival rate of 30%, whereas low-risk group survival probability did not reach 50%, and had 3-year survival rate of 71%. As a powerful predictor of 3-year recurrence-free survival in OSCC patients, the newly developed biomarkers panel risk classifier will facilitate patient counseling for personalized treatment.
Phage-mediated horizontal transfer of a Staphylococcus aureus virulence-associated genomic island
Authors: Moon Bo Youn , Park Joo Youn , Hwang Sun Yung , Robinson D. Ashley , Thomas Jonathan C. , Fitzgerald J. Ross , Park Yong Ho , Seo Keun Seok
Published: April 2015

Staphylococcus aureus is a major pathogen of humans and animals. The capacity of S. aureus to adapt to different host species and tissue types is strongly influenced by the acquisition of mobile genetic elements encoding determinants involved in niche adaptation. The genomic islands νSaα and νSaβ are found in almost all S. aureus strains and are characterized by extensive variation in virulence gene content. However the basis for the diversity and the mechanism underlying mobilization of the genomic islands between strains are unexplained. Here, we demonstrated that the genomic island, νSaβ, encoding an array of virulence factors including staphylococcal superantigens, proteases and leukotoxins, in addition to bacteriocins, was transferrable in vitro to human and animal strains of multiple S. aureus clones via a resident prophage. The transfer of the νSaβ appears to have been accomplished by multiple conversions of transducing phage particles carrying overlapping segments of the νSaβ. Our findings solve a long-standing mystery regarding the diversification and spread of the genomic island νSaβ, highlighting the central role of bacteriophages in the pathogenic evolution of S. aureus.
Hierarchical coated metal hydroxide nanoconstructs as potential controlled release carriers of photosensitizer for skin melanoma
Authors: Kankala Ranjith Kumar , Kuthati Yaswanth , Liu Chen-Lun , Lee Chia-Hung
Published: April 2015

Inorganic nanostructured ensembles containing an anionic clay matrix with layered double hydroxide (LDH) were designed in nanooncology for photosensitizer delivery.
Imaging phosphorylated peptide distribution in human lens by MALDI MS
Authors: Jiao Jing , Miao Aizhu , Zhang Ying , Fan Qi , Lu Yi , Lu Haojie
Published: April 2015

A new strategy for on-tissue dephosphorylation treatment was established for phosphorylated peptide distribution by mass spectrometry imaging.
A peptide nucleic acid-functionalized carbon nitride nanosheet as a probe for in situ monitoring of intracellular microRNA
Authors: Liao Xianjiu , Wang Quanbo , Ju Huangxian
Published: April 2015

In situintracellular detection of miRNA with an f-CNNS probe.
Online monitoring the isomerization of an azobenzene-based dendritic bolaamphiphile using ion mobility-mass spectrometry
Authors: Urner Leonhard H. , Thota Bala N. S. , Nachtigall Olaf , Warnke Stephan , von Helden Gert , Haag Rainer , Pagel Kevin
Published: April 2015

The isomerization process of a new azobenzene-based bolaamphiphile was monitored online using ion mobility-mass spectrometry.
Engineering of Sn–porphyrin networks on the silica surface: sensing of nitrophenols in water
Authors: Ko Ju Hong , Moon Jong Hun , Kang Narae , Park Joon Hyun , Shin Hee-Won , Park Nojin , Kang Sungah , Lee Sang Moon , Kim Hae Jin , Ahn Tae Kyu , Lee Jin Yong , Son Seung Uk
Published: April 2015

Sn–porphyrin networks were engineered on the silica surface using the TLC plate. The resultant system showed emission-based selective and efficient sensing performance toward nitrophenols in water.
An ionothermally synthesized Mg-based coordination polymer as a precursor for preparing porous carbons
Authors: Wu Zhao-Feng , Tan Bin , Du Cheng-Feng , Feng Mei-Ling , Xie Zai-Lai , Huang Xiao-Ying
Published: April 2015

An ionothermally synthesized Mg-CP has been utilized as the first Mg-based precursor for preparing porous carbons through thermal decomposition.
Is seven the minimum number of water molecules per ion pair for assured biological activity in ionic liquid–water mixtures?
Authors: Ohno Hiroyuki , Fujita Kyoko , Kohno Yuki
Published: April 2015

The biological activity and phase transition behaviour of IL–water mixtures, called hydrated ILs, were found to change non-linearly at a water molecule to ion pair ratio of around 7 : 1.
Viscosity minima in binary mixtures of ionic liquids + molecular solvents
Authors: Tariq M. , Shimizu K. , Esperança J. M. S. S. , Canongia Lopes J. N. , Rebelo L. P. N.
Published: April 2015

Selected mixtures of ionic liquids and amino-alcohols exhibit viscosity minima. The interplay of their unique interactions explains such anomalous effects.
The mechanism of hydrogen evolution in Cu(bztpen)-catalysed water reduction: a DFT study
Authors: Liao Rong-Zhen , Wang Mei , Sun Licheng , Siegbahn Per E. M.
Published: April 2015

DFT calculations suggest that hydrogen evolution proceeds via coupling of a Cu(ii)-hydride and a pendant pyridinium.
Hydrothermal synthesis of Group 13 metal trifluoride complexes with neutral N-donor ligands
Authors: Bhalla Rajiv , Levason William , Luthra Sajinder K. , McRobbie Graeme , Monzittu Francesco M. , Palmer Jazmyn , Reid Gillian , Sanderson George , Zhang Wenjian
Published: April 2015

MF3·3H2O (M = Al, Ga or In) react with neutral imine ligands under hydrothermal conditions to yield mer-trifluoro complexes with extensive H-bonding.
Multiscale characterization of ageing and cancer progression by a novel network entropy measure
Authors: Menichetti Giulia , Bianconi Ginestra , Castellani Gastone , Giampieri Enrico , Remondini Daniel
Published: April 2015

We characterize cancer and ageing cell states with a multiscale network entropy approach, measuring “parameter space” available to the cell.
Defensive symbioses of animals with prokaryotic and eukaryotic microorganisms
Authors: Flórez Laura V. , Biedermann Peter H. W. , Engl Tobias , Kaltenpoth Martin
Published: April 2015

Many organisms team up with symbiotic microbes for defense against predators, parasites, parasitoids, or pathogens. Here we review the known defensive symbioses in animals and the microbial secondary metabolites responsible for providing protection to the host.
R2R-printed inverted OPV modules – towards arbitrary patterned designs
Authors: Välimäki M. , Apilo P. , Po R. , Jansson E. , Bernardi A. , Ylikunnari M. , Vilkman M. , Corso G. , Puustinen J. , Tuominen J. , Hast J.
Published: April 2015

R2R fabrication of inverted OPV modules using gravure and rotary screen printing techniques showing the potential of direct 2D printing in the patterning of arbitrarily shaped and sized features.
Intramolecular oxidative coupling: I2/TBHP/NaN3-mediated synthesis of benzofuran derivatives
Authors: Xu Wengang , Li Qingcui , Cao Chuanpeng , Zhang Fanglin , Zheng Hua
Published: April 2015

A novel intramolecular oxidative coupling reaction has been established to prepare benzofuran derivatives via direct C(sp2)–H functionalization for the formation of C–O bonds. This transformation is mediated by I2/TBHP/NaN3 under metal-free conditions and a catalytic amount of NaN3 plays a crucial role in the reaction.
A lactone-fused cyclohexadiene as a versatile platform for diversified synthesis of 5,6,5-tricyclic scaffolds
Authors: Shibuya M. , Sudoh T. , Kawamura T. , Yamamoto Y.
Published: April 2015

A new lactone-fused cyclohexadiene platform for the stereoselective synthesis of differently functionalized 5,6,5-tricyclic scaffolds.
Thermochromic polyethylene films doped with perylene chromophores: experimental evidence and methods for characterization of their phase behaviour
Authors: Carlotti Marco , Gullo Giuseppa , Battisti Antonella , Martini Francesca , Borsacchi Silvia , Geppi Marco , Ruggeri Giacomo , Pucci Andrea
Published: April 2015

LLDPE films doped with aggregachromic PE-Pery fluorophores were proposed as a thermochromic system in the 30–70 °C regime.
Nb-doped VOx/CeO2 catalyst for NH3-SCR of NOx at low temperatures
Authors: Lian Zhihua , Liu Fudong , He Hong , Liu Kuo
Published: April 2015

The Nb-1VOx/CeO2 catalyst exhibited higher NH3-SCR activity than 3V2O5–10WO3/TiO2 and also showed excellent SO2/H2O resistance.
Enhanced thermal stability of polystyrene by graphitic carbon nitride/spinel ZnCo2O4 nanohybrids and the catalytic mechanism investigation
Authors: Shi Yongqian , Zhu Yulu , Yu Bin , Gui Zhou , She Shike , Yuen Richard K. K. , Liu Hui , Hu Yuan
Published: April 2015

Spinel ZnCo2O4 has shown great superiorities in the fields of catalyst and energy.
Polymer encapsulated scorpionate Eu3+ complexes as novel hybrid materials for high performance luminescence applications
Authors: Machado Kelly , Mukhopadhyay Suman , Videira Romeu A. , Mishra Jaya , Mobin Shaikh M. , Mishra Gopal S.
Published: April 2015

Tri-pyrazolyl methane europium complex, [Eu{HC(pz)3}(H2O)6]Cl3 with PMMA gel, PVA gel and HMS-PVA, have been synthesized and checked for unit mass luminescence emission and lifetime application.
Controllable synthesis of InTaO4 catalysts of different morphologies using a versatile sol precursor for photocatalytic evolution of H2
Authors: Zeng Gui-Sheng , Yu Jian , Zhu Hong-Yun , Liu Hui-Long , Xing Qiu-Ju , Bao Shao-Kui , He Shun , Zou Jian-Ping , Au Chak-Tong
Published: April 2015

For the first time, InTaO4 photocatalysts with different morphologies and structures were facilely prepared using a versatile sol precursor.
Structural, dielectric and magnetic investigations on Al3+substituted Zn-ferrospinels
Authors: Kumari Naveen , Kumar Vinod , Singh S. K.
Published: April 2015

A series of ZnAlxFe2−xO4(0.1 ≤x≤ 0.5) ferrospinels has been prepared by chemical co-precipitation method to understand the effect of Al3+substitution on the structural, dielectric and magnetic response of ZnFe2O4nanoparticles.
Synthesis and H2S sensing performance of MoO3/Fe2(MoO4)3 yolk/shell nanostructures
Authors: Gao Xinming , Li Chunyan , Yin Zhuoxun , Chen Yujin
Published: April 2015

A facile method was developed to fabricate MoO3/Fe2(MoO4)3 yolk/shell nanostructures with small pores, exhibiting good H2S gas sensing performance including high sensor response, short recovery and response times, and good selectivity and stability.
Chiral alkaline earth metal complexes with M–Se direct bond (M = Mg, Ca, Sr, Ba): syntheses, structures and ε-caprolactone polymerisation
Authors: Kottalanka Ravi K. , Harinath Adimulam , Panda Tarun K.
Published: April 2015

Synthesis and structural details of enantiomerically pure alkaline earth metal complexes (Mg, Ca, Sr, Ba) supported by chiral phosphinoselenoic amides are reported.
Identifying the existence of highly-fluorescent carboxylic group-rich carbon nanodots during a one-pot synthesis of branched polyethylenimine-passivated amine group-rich carbon nanodots
Authors: Liu Dan-Dan , Su Hua , Cao Qian , Le Xue-Yi , Mao Zong-Wan
Published: April 2015

The co-existence of carboxylic group-rich C-Dots and amine group-rich C-Dots during the one-pot pyrolysis of citric acid and bPEI was identified for the first time.
Highly crystalline Prussian blue/graphene composites for high-rate performance cathodes in Na-ion batteries
Authors: Prabakar S. J. Richard , Jeong Jaehyang , Pyo Myoungho
Published: April 2015

Slow ion release facilitated synthesis of highly crystalline Prussian blue/graphene oxide composite as a Na ion battery cathode.
Realization of color tuning via solid-solution and energy transfer in Ca3−xSrx(PO4)2:Eu2+,Mn2+phosphors
Authors: Tang Wanjun , Zhang Zheng
Published: April 2015

Based on Grassman's law of color mixing, the fine color tuning of Ca3−xSrx(PO4)2:Eu2+,Mn2+is realizedviasolid-solution and energy transfer.
Enhanced electro-optic activity from the triarylaminophenyl-based chromophores by introducing heteroatoms to the donor
Authors: Yang Yuhui , Liu Fenggang , Wang Haoran , Bo Shuhui , Liu Jialei , Qiu Ling , Zhen Zhen , Liu Xinhou
Published: April 2015

Introducing the heteroatom to the TAA donor can efficiently improve the electron-donating ability and enhance EO activity.
Peak current‐controlled CRM flyback PFC converter with square of line voltage‐compensated primary current envelope
Authors: He Junpeng , Xu Jianping , Yan Tiesheng
Published: April 2015

A peak current control technique for a flyback power factor correction (PFC) converter operating in critical conduction mode (CRM) is proposed. By using the square of the line voltage to compensate the peak current envelope of the primary current, the input current distortion of the traditional peak current‐controlled CRM flyback PFC converter can be eliminated, and the unity power factor and low total harmonic distortion (THD) can be obtained. The operating principles and characteristics of the proposed peak current‐controlled CRM flyback PFC converter are analysed. Experimental results of a 30 W prototype show that the power factor and THD of the proposed peak current‐controlled CRM flyback PFC converter are better than those of the traditional peak current‐controlled CRM flyback PFC converter.
Improved reversible data hiding for encrypted images using full embedding strategy
Authors: Li Ming , Xiao Di , Kulsoom Ayesha , Zhang Yushu
Published: April 2015

An improved version of Li et al.’s method of reversible data hiding of encrypted images is proposed. The original work partitions the encrypted image into two sets, and only one set is used for data embedding. After carrying out a feasibility analysis, the full embedding strategy is employed. Accordingly, the data embedding capacity is dilated. In addition, the corresponding new fluctuation measurement is designed for the full embedding strategy. The experimental results reveal that the full embedding strategy is effective and also indicate that using the new fluctuation measurement the performance is further augmented. The proposed method outperforms other works in terms of performance.
Equivalent circuit model of MIMO based on coupling matrix
Authors: Wu Rui‐Zhi , Wang Peng , Li Rui‐Peng , Zheng Qiang
Published: April 2015

An equivalent circuit model of coupled antennas for the multiple‐input multiple‐output (MIMO) system based on coupling matrix theory is presented. It is demonstrated that a four‐port network including two resonators can be a good description of MIMO antennas such as asymmetric coplanar strip fed antennas. The equivalent circuit is established by coupling matrix extraction which is a widely used method in the coupling matrix analysis of filters. This equivalent circuit model for the MIMO system should be helpful in MIMO or decoupling network designs.
Multiple‐antenna phase‐gradient detection for OAM radio communications
Authors: Cano E. , Allen B.
Published: April 2015

Two new multiple‐antenna phase‐gradient detection schemes for orbital angular momentum (OAM) communication systems are presented. Their bit error rate performances are obtained by means of Monte Carlo simulations. Results show that their performance is highly dependent on the circular separation among the receiver antennas. The paired‐antenna phase‐gradient receiver outperforms the uniformly spaced antenna receiver when a large number of antennas are used.
Subwavelength grating Bragg grating filters in silicon‐on‐insulator
Authors: Wang J. , Glesk I. , Chen L.R.
Published: April 2015

Narrowband filters based on Bragg gratings (BGs) in subwavelength grating (SWG) waveguides in silicon‐on‐insulator are reported. The SWG BGs are fabricated using electron beam lithography with a single etch. For SWG BGs 1.12 mm in length, the measured 3 dB bandwidths are ∼0.5 nm, and they have a peak reflectivity as high as 94.4% in the C‐band.
Sensor pattern noise and image similarity for picture‐to‐identity linking
Authors: Satta Riccardo , Ciardulli Andrea
Published: April 2015

Picture sharing through social networks has become a prominent phenomenon, producing a large amount of data that law enforcers may be entitled to use, under the proper legal framework, as a source of information for investigating a crime. In this work, the authors exploit digital camera ‘fingerprinting’ based on noise residuals (sensor pattern noise or SPN) to achieve a novel forensic task, named picture‐to‐identity linking. It consists of finding social network accounts that possibly belong to the author of a certain photo (e.g. showing illegal content). The rationale is that the author of the offending photo has likely used the same camera for taking other (legal) pictures, and posted them in a social network account. The authors extend a previous work on the topic by coupling SPN with visual image similarity, a useful cue when pictures have been taken in the same environment (e.g. a room). The authors also improve the framework by allowing for multiple‐image queries, and thoroughly evaluate the performance on two corpora of images from social network accounts, including the impact of image modifications. Reported results show a robust improvement with respect to the previous work, and prove the usefulness of picture‐to‐identity as an aid for digital forensic investigations.
Selected-ion flow tube temperature-dependent measurements for the reactions of O2+ with N atoms and N2+ with O atoms
Authors: Martinez Oscar , Sanchez Jenny C. , Ard Shaun G. , Li Anyang , Melko Joshua J. , Shuman Nicholas S. , Guo Hua , Viggiano Albert A.
Published: April 2015

The temperature variation of rate constants has been measured for the gas phase reactions of the oxycation O2+ with N atoms and of N2+ with O atoms from 120 to 400 K using a variable temperature-selected ion flow tube. Measured room temperature rate constants, 0.75 × 10−10 cm3 s−1 (±30%) for O2+ with N and 1.4 × 10−10 cm3 s−1 (±30%) for N2+ with O, are in agreement with previously reported values. A temperature dependence of T−0.7(±0.3) is observed for the O2+ + N reaction; however, the N2+ + O reaction is found to be independent of temperature. Calculations at varying levels of theory were used in tandem with experiments to evaluate likely pathways in potential energy surfaces for the reactions of concern.
Transport of Brownian particles in a narrow, slowly varying serpentine channel
Authors: Wang Xinli , Drazer German
Published: April 2015

We study the transport of Brownian particles under a constant driving force and moving in channels that present a varying centerline but have constant aperture width (serpentine channels). We investigate two types of channels, solid channels, in which the particles are geometrically confined between solid walls and soft channels, in which the particles are confined by the potential energy landscape. We consider the limit of narrow, slowly varying channels, i.e., when the aperture and the variation in the position of the centerline are small compared to the length of a unit cell in the channel (wavelength). We use the method of asymptotic expansions to determine both the average velocity (or mobility) and the effective dispersion coefficient of the particles. We show that both solid and soft-channels have the same effects on the transport properties up to leading order correction. Including the next order correction, we obtain that the mobility in a solid-channel is smaller than that in a soft-channel. However, we discuss an alternative definition of the effective width of a soft channel that leads to equal mobilities up to second order terms. Interestingly, in both cases, the corrections to the mobility of the particles are independent of the Péclet number, and the Einstein-Smoluchowski relation is satisfied.
Calculating singlet excited states: Comparison with fast time-resolved infrared spectroscopy of coumarins
Authors: Hanson-Heine Magnus W. D. , Wriglesworth Alisdair , Uroos Maliha , Calladine James A. , Murphy Thomas S. , Hamilton Michelle , Clark Ian P. , Towrie Michael , Dowden James , Besley Nicholas A. , George Michael W.
Published: April 2015

In contrast to the ground state, the calculation of the infrared (IR) spectroscopy of molecular singlet excited states represents a substantial challenge. Here, we use the structural IR fingerprint of the singlet excited states of a range of coumarin dyes to assess the accuracy of density functional theory based methods for the calculation of excited state IR spectroscopy. It is shown that excited state Kohn-Sham density functional theory provides a high level of accuracy and represents an alternative approach to time-dependent density functional theory for simulating the IR spectroscopy of singlet excited states.
Impact of first-principles properties of deuterium–tritium on inertial confinement fusion target designs
Authors: Hu S. X. , Goncharov V. N. , Boehly T. R. , McCrory R. L. , Skupsky S. , Collins L. A. , Kress J. D. , Militzer B.
Published: April 2015

A comprehensive knowledge of the properties of high-energy-density plasmas is crucial to understanding and designing low-adiabat, inertial confinement fusion (ICF) implosions through hydrodynamic simulations. Warm-dense-matter (WDM) conditions are routinely accessed by low-adiabat ICF implosions, in which strong coupling and electron degeneracy often play an important role in determining the properties of warm dense plasmas. The WDM properties of deuterium–tritium (DT) mixtures and ablator materials, such as the equation of state, thermal conductivity, opacity, and stopping power, were usually estimated by models in hydro-codes used for ICF simulations. In these models, many-body and quantum effects were only approximately taken into account in the WMD regime. Moreover, the self-consistency among these models was often missing. To examine the accuracy of these models, we have systematically calculated the static, transport, and optical properties of warm dense DT plasmas, using first-principles (FP) methods over a wide range of densities and temperatures that cover the ICF “path” to ignition. These FP methods include the path-integral Monte Carlo (PIMC) and quantum-molecular dynamics (QMD) simulations, which treat electrons with many-body quantum theory. The first-principles equation-of-state table, thermal conductivities (κQMD), and first principles opacity table of DT have been self-consistently derived from the combined PIMC and QMD calculations. They have been compared with the typical models, and their effects to ICF simulations have been separately examined in previous publications. In this paper, we focus on their combined effects to ICF implosions through hydro-simulations using these FP-based properties of DT in comparison with the usual model simulations. We found that the predictions of ICF neutron yield could change by up to a factor of ∼2.5; the lower the adiabat of DT capsules, the more variations in hydro-simulations. The FP-based properties of DT are essential for designing ICF ignition targets. Future work on first-principles studies of ICF ablator materials is also discussed.
Practical uncertainty reduction and quantification in shock physics measurements
Authors: Akin M. C. , Nguyen J. H.
Published: April 2015

We report the development of a simple error analysis sampling method for identifying intersections and inflection points to reduce total uncertainty in experimental data. This technique was used to reduce uncertainties in sound speed measurements by 80% over conventional methods. Here, we focused on its impact on a previously published set of Mo sound speed data and possible implications for phase transition and geophysical studies. However, this technique’s application can be extended to a wide range of experimental data.
Topology of classical molecular optimal control landscapes for multi-target objectives
Authors: Joe-Wong Carlee , Ho Tak-San , Rabitz Herschel , Wu Rebing
Published: April 2015

This paper considers laser-driven optimal control of an ensemble of non-interacting molecules whose dynamics lie in classical phase space. The molecules evolve independently under control to distinct final states. We consider a control landscape defined in terms of multi-target (MT) molecular states and analyze the landscape as a functional of the control field. The topology of the MT control landscape is assessed through its gradient and Hessian with respect to the control. Under particular assumptions, the MT control landscape is found to be free of traps that could hinder reaching the objective. The Hessian associated with an optimal control field is shown to have finite rank, indicating an inherent degree of robustness to control noise. Both the absence of traps and rank of the Hessian are shown to be analogous to the situation of specifying multiple targets for an ensemble of quantum states. Numerical simulations are presented to illustrate the classical landscape principles and further characterize the system behavior as the control field is optimized.
Subsystem real-time time dependent density functional theory
Authors: Krishtal Alisa , Ceresoli Davide , Pavanello Michele
Published: April 2015

We present the extension of Frozen Density Embedding (FDE) formulation of subsystem Density Functional Theory (DFT) to real-time Time Dependent Density Functional Theory (rt-TDDFT). FDE is a DFT-in-DFT embedding method that allows to partition a larger Kohn-Sham system into a set of smaller, coupled Kohn-Sham systems. Additional to the computational advantage, FDE provides physical insight into the properties of embedded systems and the coupling interactions between them. The extension to rt-TDDFT is done straightforwardly by evolving the Kohn-Sham subsystems in time simultaneously, while updating the embedding potential between the systems at every time step. Two main applications are presented: the explicit excitation energy transfer in real time between subsystems is demonstrated for the case of the Na4 cluster and the effect of the embedding on optical spectra of coupled chromophores. In particular, the importance of including the full dynamic response in the embedding potential is demonstrated.
Steady state effects in a two-pulse diffusion-weighted sequence
Authors: Zubkov Mikhail , Stait-Gardner Timothy , Price William S. , Stilbs Peter
Published: April 2015

In conventional nuclear magnetic resonance (NMR) diffusion measurements a significant amount of experimental time is used up by magnetization recovery, serving to prevent the formation of the steady state, as in the latter case the manifestation of diffusion is modulated by multiple applications of the pulse sequence and conventional diffusion coefficient inference procedures are generally not applicable. Here, an analytical expression for diffusion-related effects in a two-pulse NMR experiment (e.g., pulsed-gradient spin echo) in the steady state mode (with repetition times less than the longitudinal relaxation time of the sample) is derived by employing a Fourier series expansion within the solution of the Bloch-Torrey equations. Considerations are given for the transition conditions between the full relaxation and the steady state experiment description. The diffusion coefficient of a polymer solution (polyethylene glycol) is measured by a two-pulse sequence in the full relaxation mode and for a range of repetition times, approaching the rapid steady state experiment. The precision of the fitting employing the presented steady state solution by far exceeds that of the conventional fitting. Additionally, numerical simulations are performed yielding results strongly supporting the proposed description of the NMR diffusion measurements in the steady state.
Electrostatics on the sphere with applications to Monte Carlo simulations of two dimensional polar fluids
Authors: Caillol Jean-Michel
Published: April 2015

We present two methods for solving the electrostatics of point charges and multipoles on the surface of a sphere, i.e., in the space S2, with applications to numerical simulations of two-dimensional (2D) polar fluids. In the first approach, point charges are associated with uniform neutralizing backgrounds to form neutral pseudo-charges, while in the second, one instead considers bi-charges, i.e., dumbells of antipodal point charges of opposite signs. We establish the expressions of the electric potentials of pseudo- and bi-charges as isotropic solutions of the Laplace-Beltrami equation in S2. A multipolar expansion of pseudo- and bi-charge potentials leads to the electric potentials of mono- and bi-multipoles, respectively. These potentials constitute non-isotropic solutions of the Laplace-Beltrami equation, the general solution of which in spherical coordinates is recast under a new appealing form. We then focus on the case of mono- and bi-dipoles and build the theory of dielectric media in S2. We notably obtain the expression of the static dielectric constant of a uniform isotropic polar fluid living in S2 in terms of the polarization fluctuations of subdomains of S2. We also derive the long range behavior of the equilibrium pair correlation function under the assumption that it is governed by macroscopic electrostatics. These theoretical developments find their application in Monte Carlo simulations of the 2D fluid of dipolar hard spheres. Some preliminary numerical experiments are discussed with a special emphasis on finite size effects, a careful study of the thermodynamic limit, and a check of the theoretical predictions for the asymptotic behavior of the pair correlation function.
Fundamental solutions in a half space of two-dimensional hexagonal quasicrystal and their applications
Authors: Wang T. , Li X. Y. , Zhang X. , Müller R.
Published: April 2015

Fundamental phonon-phason field in a half-infinite space of two-dimensional hexagonal quasicrystal is derived, on the basis of general solutions in terms of quasi-harmonic functions, by virtue of the trial-and-error technique. Extended Boussinesq and Cerruti problems are studied. Appropriate potential functions are assumed and corresponding fundamental solutions are explicitly derived in terms of elementary functions. The boundary integral equations governing the contact and crack problems are constructed from the present fundament solutions. The obtained analytical solutions can serve as guidelines for future indentation tests via scanning probe microscopy and atomic force microscopy methods.
Electron paramagnetic resonance and Raman spectroscopy studies on carbon-doped MgB2 superconductor nanomaterials
Authors: Bateni Ali , Erdem Emre , Repp Sergej , Acar Selcuk , Kokal Ilkin , Häßler Wolfgang , Weber Stefan , Somer Mehmet
Published: April 2015

Undoped and carbon-doped magnesium diboride (MgB2) samples were synthesized using two sets of mixtures prepared from the precursors, amorphous nanoboron, and as-received amorphous carbon-doped nanoboron. The microscopic defect structures of carbon-doped MgB2 samples were systematically investigated using X-ray powder diffraction, Raman and electron paramagnetic resonance spectroscopy. Mg vacancies and C-related dangling-bond active centers could be distinguished, and sp3-hybridized carbon radicals were detected. A strong reduction in the critical temperature Tc was observed due to defects and crystal distortion. The symmetry effect of the latter is also reflected on the vibrational modes in the Raman spectra.
Limitations to laser machining of silicon using femtosecond micro-Bessel beams in the infrared
Authors: Grojo David , Mouskeftaras Alexandros , Delaporte Philippe , Lei Shuting
Published: April 2015

We produce and characterize high-angle femtosecond Bessel beams at 1300-nm wavelength leading to nonlinearly ionized plasma micro-channels in both glass and silicon. With microjoule pulse energy, we demonstrate controlled through-modifications in 150-μm glass substrates. In silicon, strong two-photon absorption leads to larger damages at the front surface but also a clamping of the intensity inside the bulk at a level of ≈4 × 1011 W cm−2 which is below the threshold for volume and rear surface modification. We show that the intensity clamping is associated with a strong degradation of the Bessel-like profile. The observations highlight that the inherent limitation to ultrafast energy deposition inside semiconductors with Gaussian focusing [Mouskeftaras et al., Appl. Phys. Lett. 105, 191103 (2014)] applies also for high-angle Bessel beams.
Thermal characterisation of (bio)polymers with a temperature-stabilised whispering gallery mode microsensor
Authors: Kim Eugene , Foreman Matthew R. , Baaske Martin D. , Vollmer Frank
Published: April 2015

In this work, we theoretically and experimentally investigate the thermal response of whispering gallery mode microresonators operating in an aqueous glycerol medium. Thermal stabilisation of the resonance wavelength is realised by appropriate choice of the resonator radius and glycerol concentration, with a 60 fold reduction in thermal sensitivity demonstrated. Finally, we employ our stabilised system to determine the thermal dependence of the molecular polarisability of adsorbed bovine serum albumin molecules and the refractive index of dextran and poly(diallyldimethylammonium chloride) coatings.
Radiometric calibration of optical microscopy and microspectroscopy apparata over a broad spectral range using a special thin-film luminescence standard
Authors: Valenta J. , Greben M.
Published: April 2015

Application capabilities of optical microscopes and microspectroscopes can be considerably enhanced by a proper calibration of their spectral sensitivity. We propose and demonstrate a method of relative and absolute calibration of a microspectroscope over an extraordinary broad spectral range covered by two (parallel) detection branches in visible and near-infrared spectral regions. The key point of the absolute calibration of a relative spectral sensitivity is application of the standard sample formed by a thin layer of Si nanocrystals with stable and efficient photoluminescence. The spectral PL quantum yield and the PL spatial distribution of the standard sample must be characterized by separate experiments. The absolutely calibrated microspectroscope enables to characterize spectral photon emittance of a studied object or even its luminescence quantum yield (QY) if additional knowledge about spatial distribution of emission and about excitance is available. Capabilities of the calibrated microspectroscope are demonstrated by measuring external QY of electroluminescence from a standard poly-Si solar-cell and of photoluminescence of Er-doped Si nanocrystals.
A preliminary survey of the diversity of soil algae and cyanoprokaryotes on mafic and ultramafic substrates in South Africa
Authors: Venter Arthurita , Levanets Anatoliy , Siebert Stefan , Rajakaruna Nishanta
Published: April 2015

Despite a large body of work on the serpentine-substrate effect on vascular plants, little work has been undertaken to describe algal communities found on serpentine soils derived from peridotite and other ultramafic rocks. We report a preliminary study describing the occurrence of algae and cyanoprokaryotes on mafic and ultramafic substrates from South Africa. Results suggest that slope and aspect play a key role in species diversity and community composition and, although low pH, nutrients and metal content do not reduce species richness, these edaphic features also influence species composition. Further, typical soil genera such as Leptolyngbya, Microcoleus, Phormidium, Chlamydomonas, Chlorococcum and Hantzschia were found at most sites. Chroococcus sp., Scytonema ocellatum, Nostoc linckia, Chlorotetraedron sp., Hormotilopsis gelatinosa, Klebsormidium flaccidium, Pleurococcus sp. and Tetracystis elliptica were unique to one serpentine site. The preliminary survey provides directions for future research on the serpentine-substrate effect on algal and cyanoprokaryote diversity in South Africa.
Cannabis Withdrawal and Sleep: A Systematic Review of Human Studies
Authors: Gates Peter , Albertella Lucy , Copeland Jan
Published: April 2015

Background

Sleep problems during withdrawal from cannabis use are a common experience. The details regarding how abstinence from cannabis impacts sleep are not well described. This article reviews the literature including a measure of cannabis withdrawal and sleep in humans.

Methods

A literature search using a set of cannabinoid and sleep-related terms was conducted across 8 electronic databases. Human studies that involved the administration of cannabinoids and at least 1 quantitative sleep-related measure were included. Review articles, opinion pieces, letters or editorials, case studies (final N < 8), published abstracts, posters, and non-English articles were excluded. Thirty-six publications were included in the review.

Results

Sleep was frequently interrupted during cannabis withdrawal, although the specific mechanisms of disruption remain unclear.

Conclusions

Methodological issues in the majority of studies to date preclude any definitive conclusion on the specific aspects of sleep that are affected.
Service Delivery and Pharmacotherapy for Alcohol use Disorder in the Era of Health Reform: Data from a National Sample of Treatment Organizations
Authors: Knudsen Hannah K. , Roman Paul M.
Published: April 2015

Background

Although there is a growing literature examining organizational characteristics and medication adoption, little is known about service delivery differences between specialty treatment organizations that have and have not adopted pharmacotherapy for alcohol use disorder (AUD). This study compares adopters and nonadopters across a range of treatment services, including levels of care, availability of tailored services for specific populations, treatment philosophy and counseling orientations, and adoption of comprehensive wraparound services.

Methods

In-person interviews were conducted with program leaders from a national sample of 372 organizations that deliver AUD treatment services in the United States.

Results

About 23.6% of organizations had adopted at least 1 AUD medication. Organizations offering pharmacotherapy were similar to nonadopters across many measures of levels of care, tailored services, treatment philosophy, and social services. The primary area of difference between the 2 groups was for services related to health problems other than AUD. Pharmacotherapy adopters were more likely to offer primary medical care, medications for smoking cessation, and services to address co-occurring psychiatric conditions.

Conclusions

Service delivery differences were modest between adopters and nonadopters of AUD pharmacotherapy, with the exception of health-related services. However, the greater adoption of health-related services by organizations offering AUD pharmacotherapy represents greater medicalization of treatment, which may mean these programs are more strongly positioned to respond to opportunities for integration under health reform.