bluuebunny/crossref_metadata_2025 huggingface dataset:
Microwave‐assisted extraction and determination of cyanuric acid residue in pet food samples by liquid chromatography–tandem mass spectrometry
Authors: Han Chao , Zhou Yongfang , Xia Biqi , Zhu Zhenou , Liu Cuiping , Shen Yan
Published: January 2011

Cyanuric acid (CYA) is attracting more attention due to its potential toxicity. In the present work, microwave‐assisted extraction method in combination with liquid chromatography–tandem mass spectrometry (LC‐MS/MS) was proposed for the determination of CYA in pet food samples. Among different solvents, diethylamine–acetonitrile–water mixture (1:5:4, v/v) was found to be the best one as the extractant due to the strong polarity of CYA in the pet food. An internal standard, 13C3‐labeled CYA, was used in the extractions. The separation was performed on a MERCK ZIC HILIC column (150 mm×2.1 mm id, 5 μm) with gradient elution of 20 mM ammonium acetate solution–acetonitrile. CYA was well retained (Rt=5.10 min) and eluted with good peak shape. The method could respond linearly with CYA at concentrations from 1.0 to 50 ng/mL with a quantification limit of 0.25 mg/kg. The intra‐ and inter‐day precision was less than 4.0% and the recovery of the assay was in the range of 90.4–108.1%. In the analysis of practical spiked pet food samples, the new method yielded satisfactory results. Due to its simplicity and accuracy the straightforward method is particularly suitable for routine CYA detection.
Chiral HPLC separation and absolute configuration assignment of a series of new triazole compounds
Authors: Lv Chunguang , Zhou Zhiqiang
Published: January 2011

A series of novel chiral triazole compounds were synthesized. They were separated into enantiomers by liquid chromatography on an amylose tris(3,5‐dimethylphenylcarbamate) (ADMPC) chiral stationary phase (CSP). The absolute configuration of each enantiomer of the investigated compounds was established by combined use of chemical correlation, chiral HPLC and circular dichroism (CD) spectra analysis methods. The influence of the mobile‐phase modifiers and the structure of chiral triazole compounds on the chiral separation and retention were investigated. Reversal of the elution order of some enantiomeric pairs upon using different mobile‐phase modifier was observed. The temperature effect on the chiral separation and the thermodynamic properties including enthalpy and entropy change of binding to the ADMPC‐CSP were also investigated.
Does laser type impact myocardial function following transmyocardial laser revascularization?
Authors: Estvold Soren K. , Mordini Frederico , Zhou Yifu , Yu Zu X. , Sachdev Vandana , Arai Andrew , Horvath Keith A.
Published: January 2011

Background

Transmyocardial laser revascularization (TMR) is currently clinically performed with either a CO2 or Ho:YAG laser for the treatment of severe angina. While both lasers provide symptomatic relief, there are significant differences in the laser–tissue interactions specific to each device that may impact their ability to enhance the perfusion of myocardium and thereby improve contractile function of the ischemic heart.

Methods

A porcine model of chronic myocardial ischemia was employed. After collecting baseline functional data with cine magnetic resonance imaging (MRI) and dobutamine stress echo (DSE), 14 animals underwent TMR with either a CO2 or Ho:YAG laser. Transmural channels were created with each laser in a distribution of 1/cm2 in the ischemic zone. Six weeks post‐treatment repeat MRI as well as DSE were obtained after which the animals were sacrificed. Histology was preformed to characterize the laser–tissue interaction.

Results

CO2 TMR led to improvement in wall thickening in the ischemic area as seen with cine MRI (40.3% vs. baseline, P < 0.05) and DSE (20.2% increase vs. baseline, P < 0.05). Ho:YAG treated animals had no improvement in wall thickening by MRI (−11.6% vs. baseline, P = .67) and DSE (−16.7% vs. baseline, P = 0.08). Correlative semi‐quantitative histology revealed a significantly higher fibrosis index in Ho:YAG treated myocardium versus CO2 (1.81 vs. 0.083, P < 0.05).

Conclusions

In a side‐by‐side comparison CO2 TMR resulted in improved function of ischemic myocardium as assessed by MRI and echocardiography. Ho:YAG TMR led to no improvement in regional function likely due to concomitant increase in fibrosis in the lasered area. Lasers Surg. Med. 42:906–911, 2010. © 2010 Wiley‐Liss, Inc.
Non‐sex specific genes associated with the secondary mitotic period of primordial germ cell proliferation in the gonads of embryonic rainbow trout (Oncorhynchus mykiss)
Authors: Nagler James J. , Cavileer Tim , Hunter Sam , Drew Robert , Okutsu Tomoyuki , Sakamoto Takashi , Yoshizaki Goro
Published: January 2011

The purposes of this study were to quantify the secondary proliferation of primordial germ cells (PGCs) in both sexes of rainbow trout, determine if a sex difference in the timing of PGC proliferation and eventual pre‐meiotic number exists, and use microarray data collected during this period to identify genes that are associated with PGC mitosis. The experiments used vasa‐green fluorescent protein (vasa‐GFP) transgenic rainbow trout of known genetic sex that allowed for the identification and collection of PGCs in vivo. An increase was observed in the number of PGCs counted in the gonads of both female and male embryonic vasa‐GFP rainbow trout, from 300 to 700° days (water temperature in °C × days post‐fertilization). For both sexes, a statistically significant (P < 0.05) increase in the PGC number was first noted at either 350 or 400° days of development. By 700° days, a 20–50‐fold increase in germ cell number was apparent. No sex‐specific differences in the timing of PGC proliferation or number were notable in any of the families until 700° days. In conjunction, a custom microarray based on cDNA libraries from embryonic rainbow trout gonads was used to identify genes involved in PGC mitosis. Five genes were discovered: guanine nucleotide binding protein, integral membrane protein 2B, transmembrane protein 47, C‐src tyrosine‐protein kinase, and the decorin precursor protein. All the genes identified have not been previously associated with germ cell mitosis, but are known to be involved with the cell plasma membrane and/or cell signaling pathways. Mol. Reprod. Dev. 78:181–187, 2011. © 2011 Wiley‐Liss, Inc.
Does normal fetal brain ultrasound predict normal neurodevelopmental outcome in congenital cytomegalovirus infection?
Authors: Farkas Natalie , Hoffmann Chen , Ben‐Sira Liat , Lev Dorit , Schweiger Avraham , Kidron Dvora , Lerman‐Sagie Tally , Malinger Gustavo
Published: January 2011

Objective

We evaluated the neuropsychological outcome of children with proven congenital cytomegalovirus (CMV) infection and normal consecutive fetal neurosonographic examinations.

Methods

We retrospectively reviewed laboratory and imaging findings of children with congenital CMV infection. The study group consisted of children with a positive polymerase chain reaction (PCR) in amniotic fluid and virus isolation in urine in the first week of life, and normal fetal ultrasonographic (US) examination findings, including a normal multiplanar neurosonographic evaluation. Patients with abnormal magnetic resonance (MR) findings were not excluded. The study and control groups were evaluated for cognitive, language, and motor development at one follow‐up examination conducted at 11–81 months of age.

Results

Children with congenital CMV infection and normal fetal brain findings in the US examination did not differ from the control group in terms of cognitive, language, motor, emotional–behavioral, and executive functioning. There were no differences between congenitally infected children who had a normal fetal brain MR examination and children whose fetal brain MR examination raised suspicion of a possible brain insult.

Conclusions

Normal neurosonographic examinations during pregnancy appear to predict a normal early neuropsychological outcome in fetuses with congenital CMV infection. Outcome did not correlate with suspected abnormal white matter on fetal MR imaging. Copyright © 2011 John Wiley & Sons, Ltd.
Absolute quality evaluation of protein model structures using statistical potentials with respect to the native and reference states
Authors: Shirota Matsuyuki , Ishida Takashi , Kinoshita Kengo
Published: January 2011

In protein structure prediction, it is crucial to evaluate the degree of native‐likeness of given model structures. Statistical potentials extracted from protein structure data sets are widely used for such quality assessment problems, but they are only applicable for comparing different models of the same protein. Although various other methods, such as machine learning approaches, were developed to predict the absolute similarity of model structures to the native ones, they required a set of decoy structures in addition to the model structures. In this paper, we tried to reformulate the statistical potentials as absolute quality scores, without using the information from decoy structures. For this purpose, we regarded the native state and the reference state, which are necessary components of statistical potentials, as the good and bad standard states, respectively, and first showed that the statistical potentials can be regarded as the state functions, which relate a model structure to the native and reference states. Then, we proposed a standardized measure of protein structure, called native‐likeness, by interpolating the score of a model structure between the native and reference state scores defined for each protein. The native‐likeness correlated with the similarity to the native structures and discriminated the native structures from the models, with better accuracy than the raw score. Our results show that statistical potentials can quantify the native‐like properties of protein structures, if they fully utilize the statistical information obtained from the data set. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Big bang methodology applied to atomic clusters
Authors: Centeno Jesus , Fuentealba Patricio
Published: January 2011

An implementation of a novel strategy for cluster geometry optimization, using a stochastic method, is applied. This algorithm is based on the spirit of Big Bang theory. The strategy consists on a three‐step procedure; a semiempirical optimization of the 1000n super compressed starting geometries, followed by two DFT optimizations of the resulting structures. The methodology is applied to the study of alkali metal clusters (Lin with 3 ≤ n ≤ 20, Nan with 3 ≤ n ≤ 13, and Kn with 3 ≤ n ≤ 10) structures and properties. With this new technique, we were able to find new isomers. The structures of alkali clusters show a large number of pentagonal pyramids and tetrahedral subunits. Most important electronic properties have been discussed and compared with different calculations and experimental data. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
A quantum chemical study on the antioxidant properties of aureusidin and bracteatin
Authors: Kumar K. Senthil , Kumaresan R.
Published: January 2011

The radical scavenging activities of the two flavonoids, aureusidin and bracteatin, have been explored by using density functional theory (DFT) with the B3LYP exchange correlation functional. These compounds are characterized by a high antioxidant activity which confers to them pharmacological properties that are useful for the treatment of several diseases. The minimum energy conformations obtained from the energy scan is a further geometry optimization performed at the B3LYP‐DFT level with 6‐311G** basis set. Harmonic vibrational frequencies have been performed on the optimized structures to ensure that the geometries obtained were real minima. For radicals, the geometry optimizations and frequency calculations were also done at the same mode of theory. Single point energy was calculated at the same level of theory in the gas phase and in two solvents with different polarities (water and benzene) with the aim of computing the bond dissociation enthalpy (BDE) for the OH bonds and the ionization potentials (IPs). The OH BDE parameter calculated for each OH group seems to be the best indicator of the antiradical property of these compounds. This demonstrates the importance of the H‐atom transfer mechanism to explain their capacity to scavenge the free radicals. The active sites are identified. BDE for these systems do not follow the same trends in gas and solution phases. The values of reactivity‐based descriptors such as total energy, orbital energy gap, maximum hardness principle, and electronegativity are also related with the antioxidant activity. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
The study of actinide chemistry with multiconfigurational quantum chemical methods
Authors: Gagliardi Laura
Published: January 2011

The major contributions of Björn Roos to actinide chemistry, both in terms of quantum chemical method development and applications, will be reviewed. The extension of the complete active space SCF method followed by second order perturbation theory (CASSCF/CASPT2) method to a relativistic regime will be discussed, together with some of the most significant applications, like the study of U2 and UO2. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111:3302–3306, 2011
Experience with fault injection experiments for FMEA
Authors: Grunske Lars , Winter Kirsten , Yatapanage Nisansala , Zafar Saad , Lindsay Peter A.
Published: January 2011

Failure Modes and Effects Analysis (FMEA) is a widely used system and software safety analysis technique that systematically identifies failure modes of system components and explores whether these failure modes might lead to potential hazards. In practice, FMEA is typically a labor‐intensive team‐based exercise, with little tool support. This article presents our experience with automating parts of the FMEA process, using a model checker to automate the search for system‐level consequences of component failures. The idea is to inject runtime faults into a model based on the system specification and check if the resulting model violates safety requirements, specified as temporal logical formulas. This enables the safety engineer to identify if a component failure, or combination of multiple failures, can lead to a specified hazard condition. If so, the model checker produces an example of the events leading up to the hazard occurrence which the analyst can use to identify the relevant failure propagation pathways and co‐effectors. The process is applied on three medium‐sized case studies modeled with Behavior Trees. Performance metrics for SAL model checking are presented. Copyright © 2011 John Wiley & Sons, Ltd.
Cancer du sein: l’homme est aussi concerné. Étude de 21 cas
Authors: Sellal N. , Haddad H. , Bouchbika Z. , Benchakroun N. , Jouhadi H. , Tawfiq N. , Sahraoui S. , Benider A.
Published: January 2011

Introduction

Le cancer du sein, première pathologie maligne chez la femme, reste une maladie rare chez l’homme. Il représente environ 1 % des cancers du sein et moins de 1 % de l’ensemble des néoplasies masculines. L’objectif de cette étude est d’analyser les caractéristiques cliniques, histologiques et thérapeutiques du cancer du sein chez l’homme.

Patients et méthodes

Les auteurs présentent une étude descriptive menée de manière rétrospective au service de radiothérapie-oncologie du CHU Ibn-Rochd de Casablanca, entre janvier 2006 et décembre 2007, concernant une série de 21 patients de sexe masculin présentant un cancer du sein.

Résultats

L’âge médian était de 70 ans (extrêmes: 39–84). Le délai médian de consultation était de huit mois (extrêmes: 2–24). Il s’agissait, dans 16 cas, d’une tumeur rétroaréolaire dont la taille médiane était de 35 mm (extrêmes: 15–80). Les tumeurs étaient classées T2 dans 12 cas et T4 dans sept cas. Le type histologique le plus représenté était le carcinome canalaire infiltrant (CCI) [18 cas]. Le grade SBR II a été retrouvé dans 13 cas. Le taux d’envahissement ganglionnaire axillaire prouvé histologiquement était de 38 % (huit patients) et dans 14 % des cas plus de trois ganglions étaient envahis. L’effraction capsulaire n’a été retrouvée que dans quatre cas. Les récepteurs hormonaux étaient positifs dans 19 cas. La prise en charge thérapeutique a consisté en une chirurgie radicale dans 14 cas avec une chimiothérapie associée à une radiothérapie dans cinq cas, 66 % des patients ont reçu une hormonothérapie. Après un suivi moyen de 23 mois, trois malades ont développé des métastases et six malades sont encore vivants sans maladie.

Conclusion

Le cancer du sein chez l’homme est rare. Son diagnostic se fait souvent à un stade tardif. Son traitement est similaire à celui de la femme avec un retard diagnostique retentissant sur le pronostic.
Pregnancy outcome in patients treated with cervical conization for cervical intraepithelial neoplasia
Authors: Andía Daniel , Mozo de Rosales Fernando , Villasante Amparo , Rivero Borja , Díez Javier , Pérez Carlos
Published: January 2011

Objective

To examine the causal contribution of conization to premature delivery.

Methods

This was a retrospective, case‐control, multicenter study of women who underwent conization in 5 hospitals in the Basque Country (Spain) from 1998 to 2007. Three study groups were established: group A, post‐conization infant deliveries; control group B, pre‐conization infant deliveries; and control group C, infant deliveries without conization.

Results

Comparing group A with group C, there was a higher rate of preterm delivery before 35 weeks (5.3% versus 1.6%), a lower mean birth weight (3156.2 g versus 3328.5 g), and a greater prevalence of infants under 2500 g (10.6% versus 3.7%). There were no significant differences between group A and group B: preterm delivery before 35 weeks (5.3% versus 4.8%), mean birth weight (3156.2 g versus 3119.4 g), and prevalence of infants under 2500 g (10.6% versus 10.6%).

Conclusion

Pregnancy in women post‐conization was associated with a risk of preterm delivery. However, there were no significant differences between women who underwent conization before and those who underwent conization after delivery. Cervical conization does not necessarily increase the risk of preterm delivery in subsequent pregnancy. Conization should be considered an indicator of such risk because it is associated with pregnancy complications arising from socio‐epidemiologic factors present in women requiring conization that are also present in women who have premature delivery.
Patientenorientierung aus Sicht des Aktionsbündnisses Patientensicherheit e.V.
Authors: Jonitz Günther , Barth Sonja
Published: January 2011

Einleitung

Das APS versteht sich als aktives Bündnis, das Patientenorientierung mit Patientensicherheit gleichsetzt: Patientensicherheit wird verstanden als gemeinsames Anliegen aller im Gesundheitswesen aktiv und passiv Beteiligten und kann auch nur in einem gemeinsamen Vorgehen erreicht werden. „Betroffene zu Beteiligten machen“ lautet die Grundidee des APS.
GETTING READY FOR THE MARRIAGE MARKET? A COMMENT
Authors: SCHNEIDER BJÖRN , GRIMPS FLORIAN
Published: January 2011

This text comments on the article by Lundborg et al. ‘Getting ready for the marriage market? The association between divorce risks and investments in attractive body mass among married Europeans’ published in July 2007 in this journal. This commentary presents differing results from the original data using multilevel analysis for calculation. The results presented here suggest there is no significant relation between divorce risk and body mass index (BMI) among married individuals in European countries. Therefore, the primary finding of Lundborg et al. (2007) is questioned.
WE COULD HAVE LOVED AND LOST, OR WE NEVER COULD HAVE LOVE AT ALL
Authors: Conroy Mark A. , Cupples Linda
Published: January 2011

This study investigated sentence-processing strategies adopted by advanced nonnative speakers (NNSs) and native speakers (NSs) of English in the context of an English structure with which NNSs reportedly have an acquisition difficulty (e.g., Swan & Smith, 2001)—namely, modal perfect (MP). Participants read MP sentences such as He could have worked at the shoe factory and closely related analogous sentences (e.g., He could have work at the shoe factory), and reading times and errors were measured in an online grammaticality-judgment task. It was hypothesized that NSs would have a processing preference for MP sentences compared to the analogues, reflecting the primacy of syntactic information in NS processing and a preference for late closure, whereas NNSs would show no such preference because they rely less on syntactic information when processing sentences. The results revealed, however, that both NSs and NNSs read MP sentences more quickly and with fewer errors than the closely related analogues, consistent with a processing preference for MP sentences. Both groups were also influenced by word-category frequency information, which moderated, but did not fundamentally alter, their syntactic preference for MP. The significance of these findings is discussed in terms of models of second-language sentence processing and NNSs’ reported MP acquisition difficulty.
Symmetric Auslander and Bass categories
Authors: JØRGENSEN PETER , KATO KIRIKO
Published: January 2011

We define the symmetric Auslander categoryAs(R) to consist of complexes of projective modules whose left- and right-tails are equal to the left- and right-tails of totally acyclic complexes of projective modules.

The symmetric Auslander category containsA(R), the ordinary Auslander category. It is well known thatA(R) is intimately related to Gorenstein projective modules, and our main result is thatAs(R) is similarly related to what can reasonably be called Gorenstein projective homomorphisms. Namely, there is an equivalence of triangulated categorieswhereGMor(R) is the stable category of Gorenstein projective objects in the abelian categoryMor(R) of homomorphisms ofR-modules.

This result is set in the wider context of a theory forAs(R) andBs(R), the symmetric Bass category which is defined dually.
Factors associated with dietary patterns among low-income adults
Authors: Cunha Diana Barbosa , Sichieri Rosely , de Almeida Renan Moritz Varnier Rodrigues , Pereira Rosangela Alves
Published: January 2011

Objective

To describe the association of socio-economic, demographic and lifestyle characteristics with three eating patterns identified among low-income adults living in the Rio de Janeiro metropolitan area, Brazil.

Design

Data were obtained in a population-based cross-sectional study. The analysed patterns were: (i) ‘Mixed’, in which diverse foods had similar factor loadings; (ii) ‘Western’, which included items with high energy density; and (iii) ‘Traditional’, which relied in rice and beans, traditional staple foods in Brazil. Hierarchical logistic analysis was performed to estimate the association between the independent variables and each one of the dietary patterns. The variables that presented statistical significance <0·20 in the univariate analysis (χ2test) were included in the multivariate models.

Setting

Duque de Caxias, a low-income area in the Rio de Janeiro metropolitan region, Brazil.

Subjects

Adults (n1009) aged 20 to 65 years (339 men and 670 women).

Results

The ‘Mixed’ pattern was positively associated with smoking (OR = 1·58, 95 % CI 1·00, 2·48 for current smokingv. those who never smoked). The ‘Western’ pattern was positively associated with family income (OR = 3·00, 95 % CI 1·81, 4·97 for those with monthly per capita family income ≥1·0v. <0·5 times the official Brazilian minimum wage) and inversely associated with family food insecurity (OR = 0·55, 95 % CI 0·36, 0·84). The ‘Traditional’ pattern was associated with family food insecurity (OR = 1·79, 95 % CI 1·27, 2·51).

Conclusions

The results support previous findings relating improvement in economic conditions to reduced adherence to the traditional Brazilian food consumption pattern based on the combination of rice and beans.
The New Negro and Social Democracy during the Harlem Renaissance, 1917–37
Authors: Bynum Cornelius L.
Published: January 2011

This essay focuses on the conception of social justice devised by A. Philip Randolph, noted socialist, co-founder of The Messenger, and organizer of the Brotherhood of Sleeping Car Porters, and Frank R. Crosswaith, a general organizer for the International Ladies Garment Workers Union and one-time Messenger correspondent, in the aftermath of World War I. Weaving together a socialist critique of modern industrial society with a powerful vision of human freedom and equality, Randolph and Crosswaith articulated a distinctly egalitarian conception of social justice that asserted the equal right of all to benefit from society's advances. Arguing that genuine social justice was predicated on the open participation of all, they fashioned a program of reform that drew on black racial identity to frame their vision of class consciousness and, in so doing, planted the roots of an independent strain of black radicalism that was not intellectually beholden to whites. Although historical writing on the New Negro recognizes the importance of Randolph and to a lesser degree Crosswaith, this writing overlooks their innovative thought and its philosophical and political basis.
Erratum: Unraveling the viral tapestry (from inside the capsid out)
Authors: Polson Shawn W , Wilhelm Steven W , Wommack K Eric
Published: January 2011

Correction to: The ISME Journal (2011) 5, 165–168; doi:10.1038/ismej.2010.81; published online 17 June 2010 Since the publication of this paper, the authors have noticed an omission in their article. The missing text is shown here.
Comment on “Terrestrial gamma-ray flashes caused by neutron bursts above thunderclouds” [J. Appl. Phys. 105, 083301 (2009)]
Authors: Smith David M.
Published: January 2011

Paiva presented in these pages an argument that terrestrial gamma-ray flashes (TGFs) are created by the interaction of lightning-generated neutrons with nitrogen nuclei in air. I show that this model cannot produce the observed energy spectrum of TGFs, while the generally accepted model of bremsstrahlung from relativistic electrons fits the data well.
Thermal and shock induced modification inside a silica glass by focused femtosecond laser pulse
Authors: Sakakura Masaaki , Terazima Masahide , Shimotsuma Yasuhiko , Miura Kiyotaka , Hirao Kazuyuki
Published: January 2011

The femtosecond laser induced structural modification was studied by the detection of a laser induced pressure wave using a transient lens (TrL) method. The TrL signals observed at various excitation pulse energies showed that there were two thresholds of the pulse energy for the modification. Above the higher threshold, a pressure wave was observed clearly, and the amplitude of the pressure wave increased with increasing excitation pulse energy. In addition, Raman spectra at the laser irradiated region showed that the compact silica ring structures increased in the photoexcited region above the higher threshold, which suggested that the photoexcited glass was densified by a shock due to a pressure wave generation. In the energy region between the lower and higher thresholds, a pressure wave was not detected but a temporally constant refractive index change was observed. From the amplitude of the change, the temperature elevation just after the photoexcitation in this energy region was estimated to be about 1400 K. We interpreted that fast cooling from the high temperature is responsible for the modification between the lower and higher thresholds. The two modifications identified in this study should correspond to two types of damage inside a silica glass which have been observed previously. This is the first study that elucidated the difference of two types of modification from the time-resolved observation of the dynamics.
Creation of charged excitons with two-color excitation method and initialization of electron spin qubit in quantum dots
Authors: Gotoh Hideki , Sanada Haruki , Kamada Hidehiko , Yamaguchi Hiroshi , Sogawa Tetsuomi
Published: January 2011

An optical pumping method for creating charged excitons in semiconductor quantum dots is demonstrated using a two-color excitation method. This method employs two laser sources whose energies are in the resonant and barrier excitation conditions, respectively. The photoluminescence (PL) spectra of a single quantum dot clearly vary from exciton-originated PL to charged exciton-originated PL as the excitation conditions are changed. This method is applied to the initialization process of an electron spin qubit without a magnetic field, which provides a simple and effective way of implementing quantum computing with spin qubits.
Communication: A concerted mechanism between proton transfer of Zundel anion and displacement of counter cation
Authors: Koizumi Akihito , Suzuki Kimichi , Shiga Motoyuki , Tachikawa Masanori
Published: January 2011

Ab initio path integral molecular dynamics simulation of M+(H3O2−) (M = Li, Na, and K) has been carried out to analyze how the structure and dynamics of a low-barrier hydrogen-bonded Zundel anion, H3O2−, can be affected by the counter alkali metal cation, M+. Our simulation predicts that the quantum proton transfer in Zundel anion can be strongly coupled to the motion of counter cation located nearby. A smaller cation can induce larger structural distortion of the Zundel anion fragment making the proton transfer barrier higher, and hence, lower the vibrational excitation energy. It is also argued that a large H/D isotope effect is present .
Acute whole‐body vibration does not affect static jump performance
Authors: Kavanaugh Ashley , Ramsey Michael W. , Sands William A. , Haff G. Gregory , Stone Michael H.
Published: January 2011

Currently, whole‐body vibration is being used to promote enhanced performance. Many coaches and athletes believe that it can acutely enhance explosive performance and power output. However, the scientific literature is unclear as to whether this enhancement occurs. The purpose of this study was to examine the acute effects of whole‐body vibration on static jump performance, including jump height, peak force, rate of force development, and peak power. Fourteen recreationally active individuals (5 females, 9 males) participated in three separate randomized treatment sessions. Treatment 1 consisted of no vibration while treatment 2 and treatment 3 incorporated whole‐body vibration. The whole‐body vibration protocol consisted of three 30‐s bouts of vibration performed at 30 Hz and low amplitude (~3 mm) with a 30‐s rest between bouts. Treatment 1 was identical in duration to both treatments 2 and 3, but did not contain any vibration. Five minutes after each treatment, the participants performed the static jump protocols. Two (data averaged) non‐weighted static jumps and two 20 kg weighted jumps were performed. Treatments 1 vs. 2, 1 vs. 3, and 2 vs. 3 were calculated for each variable at both 0 kg and 20 kg. Jump height, peak force, rate of force development, and peak power were analysed using a one‐way analysis of variance with repeated measures. The intra‐class correlations comparing the two trials of each jump for each of the three treatments were ≥0.92. Compared with the no‐vibration condition, jump height showed a non‐significant increase as a result of whole‐body vibration for both unweighted and weighted jumps; peak force, rate of force development, and peak power were not statistically different. The results indicate that whole‐body vibration has no effect on jump height, peak force, rate of force development or peak power during static jumping.
Fatmax in children and adolescents: A review
Authors: Zakrzewski Julia , Tolfrey Keith
Published: January 2011

The purpose of this review is to summarize and critically examine the literature that has determined Fatmax in children and adolescents (young people). Maximizing fat oxidation during exercise may be beneficial for health, particularly in the management of metabolic diseases such as obesity and type 2 diabetes. Exercise intensity largely determines fat oxidation during exercise. Fatmax is the relative exercise intensity that elicits the highest fat oxidation rate and has received increasing attention in recent years. Studies in young people have demonstrated that there is considerable inter‐individual variation in Fatmax, which generally occurs between 30 and 60% of peak oxygen uptake. Factors that may influence Fatmax in young people include body composition, physical maturation, and exercise training. Several researchers have suggested that Fatmax and fat oxidation rates may be reduced in obese compared with non‐obese young people. Fatmax and fat oxidation rates may also decrease with maturational status. Much of the research on Fatmax in young people has focused on boys, with research comparing Fatmax between the sexes extremely limited. The available evidence indicates that Fatmax is similar between boys and girls, whereas absolute rates of fat oxidation may be higher in boys. The use of Fatmax as a training tool for the obese has been examined in young people and may have implications for improving fat oxidation and various health markers. However, several weaknesses may be highlighted in many studies that have identified Fatmax in young people, and inconsistencies in the methods used to determine Fatmax limit comparisons between studies. Therefore, conclusions based on these findings require further investigation. Additional research is also required to assess the influence of other factors associated with Fatmax in young people, including exercise mode, cardiorespiratory fitness, and free‐living physical activity.
Acute effects of vibration‐assisted stretching are more evident in the non‐dominant limb
Authors: McNeal Jeni R. , Edgerly Shawn , Sands William A. , Kawaguchi Jeffrey
Published: January 2011

The aim of this study was to investigate the acute effects of a vibration‐assisted static stretching intervention on enhancing split range of motion in gymnasts matched on initial range of motion. Twenty‐two female artistic gymnasts (mean age 13.8 years, s=2.3) matched for age (±6 months) and competitive level were randomly assigned to a static stretching intervention with or without simultaneous vibration. The test consisted of adopting a forward split position with the rear leg bent to 90° and held vertically against a matted block while the pelvis remained perpendicular to the lines of the two legs. The gymnast was instructed to descend into the lowest split position of her comfortable pain tolerance. Positions were videotaped and digitized creating an angle between the split legs. The stretching intervention consisted of a forward split position with emphasis on the front leg hamstring muscle group, followed by a forward lunge position with emphasis on the rear leg quadriceps muscle group. In each position, four sets of stretches were completed each of 10 s duration with 5 s of rest between sets. The experimental group performed stretches with the vibration device turned on while the control group performed the same stretches with the vibration device turned off. A pre‐test was performed to obtain baseline scores with the post‐test following immediately after the vibration or control stretching intervention. Difference scores were calculated between the pre‐test and post‐test for each gymnast, and compared between groups using independent t‐tests. Results showed significant post‐test differences between the vibration and non‐vibration groups (mean difference 12.2±5.2° vibration vs. 7.8±3.5° non‐vibration, P=0.030) in the non‐dominant limb, but no significant differences in the dominant limb (mean difference 10.2±4.3° vibration vs. 7.9±6.1° non‐vibration, P=0.32). Vibration‐assisted static stretching may provide a greater stimulus for range of motion improvements in limbs that have a lower initial level of flexibility.
Mechanistic analysis of massive endocytosis in relation to functionally defined surface membrane domains
Authors: Hilgemann Donald W. , Fine Michael
Published: January 2011

A large fraction of endocytosis in eukaryotic cells occurs without adaptors or dynamins. Here, we present evidence for the involvement of lipid domains in massive endocytosis (MEND) activated by both large Ca transients and amphipathic compounds in baby hamster kidney and HEK293 cells. First, we demonstrate functional coupling of the two MEND types. Ca transients can strongly facilitate detergent-activated MEND. Conversely, an amphipath with dual alkyl chains, ditridecylphthalate, is without effect in the absence of Ca transients but induces MEND to occur within seconds during Ca transients. Ca transients, like amphipaths, enhance the extraction of lipids from cells by β-cyclodextrins. Second, we demonstrate that electrical and/or optical signals generated by selected membrane probes are nearly insensitive to MEND, suggesting that those probes segregate into membrane domains that are not taken up by MEND. Triphenylphosphoniums are increasingly excluded from domains that internalize as the carbon chain length increases from 4 to 12. The small cationic membrane dye, FM 4–64, binds well to domains that internalize, whereas a closely related dye with a larger hydrophobic moiety, di-4-ANEPPDHQ (ANEPPDHQ) is excluded. Multiple carrier-type ionophores and a small amphipathic anion, niflumic acid, are also excluded. Probes with modest MEND sensitivity include the hydrophobic anion, dipicrylamine, carbonyl cyanide m-chlorophenylhydrazone, and NBD-phosphatidylethanolamine. Third, we demonstrate that large Ca transients can strongly enhance the extracellular binding of several membrane probes, monitored electrically or optically, consistent with a more disordered membrane with more amphipath-binding sites. Fluorescence shifts of ANEPPDHQ report increased disorder of the extracellular monolayer after large Ca transients, consistent with an increased propensity of the membrane to phase separate and vesiculate. Collectively, the results indicate that >50% of the outer monolayer is ordered and can be selectively internalized during MEND responses initiated by two very different cell perturbations.
Dynamic behaviour of silicon carbide nanowires under high and extreme strain rates: a molecular dynamics study
Authors: Tsuzuki H , Rino J P , Branicio P S
Published: January 2011

Molecular dynamics simulations are used to investigate the dynamic behaviour of SiC nanowires under strain rates between 2 × 109 s−1 and 2 × 1011 s−1. Nanowires of different cross sections in the wurtzite (WZN) and zinc blende (ZBN) phases are considered under tensile and compressive deformation. Results show contrasts and similarities in the behaviour of WZNs and ZBNs for the lowest strain rate. (i) WZNs present a continuous structural transformation in the elastic regime under compressive deformation, to a h-MgO structure, while ZBNs display a similar kind of transformation to the β-Sn structure under tensile deformation. (ii) Under tensile deformation WZNs fail by brittle fracture while ZBNs display complex plasticity before failure. (iii) Under compressive deformation both ZBNs and WZNs show buckling and plasticity. For the highest strain rate the mechanical behaviour is similar: both WZNs and ZBNs show induced amorphization for both tensile and compressive deformations.
Phloem mobility of xenobiotics VIII. A short review
Authors: Hsu Francis C. , Kleier Daniel A.
Published: January 2011

Great strides have been made in the last 15 years in our understanding of phloem mobility of xenobiotics. The subject has been transformed from a poorly understood phenomenon to a process that can be accurately described by the physicochemical properties of the xenobiotic and the nature of the vascular system through which it moves. The basic tenet of the unified mathematical model is that the combination of the permeability and the acid dissociation constant (pKa) determines phloem mobility, and this has been largely validated for many compounds in many plant systems. More precise testing of the model is, however, difficult due to the lack of requisite knowledge on the membrane composition of the sieve tube, permeation characteristics and sieve-cell biochemistry. Furthermore, attempts to relate quantitatively a compound's intrinsic mobility to its whole-plant mobility are often confounded by competing loss mechanisms. On the practical side, there is the challenge of coming up with efficacious phloem-mobile pesticides. Considerations are forwarded to explain why so far there are numerous phloem-mobile herbicides and yet precious few such insecticides and fungicides, and why the situation might be difficult to change. The knowledge of phloem mobility is robust enough to allow specific structural prescriptions to impart such mobility to existing pesticides. However, such structural changes often lead to a reduction of pesticidal activity. Recently, it has been demonstrated that this problem can be circumvented by combining oxamyl glucuronide (a phloem-mobile pro-nematicide) with a transgenic tobacco plant harboring a root-specific β-glucuronidase gene to release oxamyl for root-knot nematode control. This propesticide and in situ activation strategy is one way to use the existing body of knowledge for practical purposes. The same principle should be generally applicable to other plant-xenobiotic technologies.
Newly Discovered Natural Hosts of Tomato chlorosis virus in Costa Rica
Authors: Solórzano-Morales A. , Barboza N. , Hernández E. , Mora-Umaña F. , Ramírez P. , Hammond R. W.
Published: January 2011

Tomato chlorosis virus (ToCV) is an emerging whitefly-transmitted crinivirus (2). In Costa Rica in 2007, ToCV was detected in field-grown and greenhouse tomato (Solanum lycopersicum L.) plants causing symptoms of severe yellowing and foliar chlorosis (1). To identify alternative hosts that may serve as virus reservoirs, 78 samples were collected from multiple species of common weeds growing adjacent to tomato nurseries in the Cartago Province, where ToCV was previously identified, during the autumn of 2008 and summer of 2009. The weeds were collected on the basis of the presence of whiteflies and/or symptoms of interveinal chlorosis, but not all samples were symptomatic for infection by ToCV. Total RNA was extracted from leaf tissue with TRI Reagent (Molecular Research Inc., Cincinnati, OH). Reverse transcription (RT)-PCR reactions were performed with the Qtaq One-Step qRT-PCR SYBR Kit (Clontech Laboratories, Mountain View, CA) and primers specific for the ToCV HSP70h gene (3). A 123-bp DNA fragment was amplified in five weeds, which were identified taxonomically as Ruta chalepensis (Rutaceae), Phytolacca icosandra (Phytolacaceae), Plantago major (Plantaginaceae), a Brassica sp. (Brassicaceae) (two samples), and a single plant of Cucurbita moschata (Cucurbitaceae) growing next to those weeds. The amplified DNA fragments were sequenced and BLAST analysis showed 100% nucleotide sequence identity with the HSP70h gene of the Florida ToCV isolate (GenBank Accession No. AY903448). To confirm the presence of ToCV in these six weed samples, conventional RT-PCR reactions were performed using primers specific for the ToCV CPm and p22 genes as described previously (1). Nucleotide sequence analysis of the amplified DNA fragments verified their identity as ToCV, with 100% sequence identity to the CPm of the ToCV isolate of Florida (Accession No. AY903448) and the p22 gene of the Cartago, Costa Rican isolate (Accession No. FJ809714). Although the number of samples analyzed is not sufficient to allow a determination of the role of weed reservoirs in ToCV epidemics in Costa Rican tomato crops, this report on the wider natural host range of ToCV in Costa Rica may lead to a better understanding of the epidemiology of this virus and be useful in the development of disease management strategies. To our knowledge this is the first report of these weeds as natural hosts of ToCV.

References: (1) R. M. Castro et al. Plant Dis. 93:970, 2009. (2) M. I. Font et al. Plant Dis. 88:82, 2004. (3) W. M. Wintermantel et al. Phytopathology 98:1340, 2008.
Planar polarization of the atypical myosin Dachs orients cell divisions in Drosophila
Authors: Mao Yanlan , Tournier Alexander L. , Bates Paul A. , Gale Jonathan E. , Tapon Nicolas , Thompson Barry J.
Published: January 2011

Tissues can grow in a particular direction by controlling the orientation of cell divisions. This phenomenon is evident in the developing Drosophila wing epithelium, where the tissue becomes elongated along the proximal–distal axis. We show that orientation of cell divisions in the wing requires planar polarization of an atypical myosin, Dachs. Our evidence suggests that Dachs constricts cell–cell junctions to alter the geometry of cell shapes at the apical surface, and that cell shape then determines the orientation of the mitotic spindle. Using a computational model of a growing epithelium, we show that polarized cell tension is sufficient to orient cell shapes, cell divisions, and tissue growth. Planar polarization of Dachs is ultimately oriented by long-range gradients emanating from compartment boundaries, and is therefore a mechanism linking these gradients with the control of tissue shape.
c‐Maf suppresses human T‐cell leukemia virus type 1 Tax by competing for CREB‐binding protein
Authors: Hieshima Kunio , Nagakubo Daisuke , Shigeta Akiko , Tanaka Yuetsu , Hoshino Hiroo , Tsukasaki Kunihiro , Yamada Yasuaki , Yoshie Osamu
Published: January 2011

Latent infection of human T‐cell leukemia virus type 1 (HTLV‐1) is considered to be preferentially associated with CCR4+ CD4+ T cells. Here we report that c‐Maf, one of the critical transcription factors for Th2 differentiation, suppresses the transcriptional activity of HTLV‐1 Tax by competing for CREB‐binding protein. Notably, c‐maf expression is selectively induced in a fraction of CCR4+ CD4+ T cells upon activation. Furthermore, c‐Maf significantly decreases Tax‐induced HTLV‐1 envelope gp46 gene expression from an infectious HTLV‐1 molecular clone and tax expression in a cell‐free HTLV‐1 infection system. Collectively, c‐Maf may play a role in latent infection of HTLV‐1 in CCR4+ CD4+ T cells by negatively regulating Tax activity. (Cancer Sci 2011; 102: 890–894)