bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes of Hydrogen Peroxide and Radical‐Scavenging Activity of Raspberry during Osmotic, Convective, and Freeze‐Drying
Authors: Novaković Miroslav M. , Stevanović Snežana M. , Gorjanović Stanislava Ž. , Jovanovic Predrag M. , Tešević Vele V. , Janković Miodrag A. , Sužnjević Desanka Ž.
Published: April 2011

Abstract:  This study was conducted to investigate the influence of different drying treatments on antioxidant (AO) activity and phenolic content of raspberry (Rubus idaeus), cultivar Willamette. Whole raspberry fruits were dried convectively (air‐drying), osmotically, and freeze‐dried. Acetone‐water extracts of fresh and dried raspberries were assessed for total phenolic content by standard Folin–Ciocalteau method. Two AO assays were applied, a recently developed direct current (DC) polarographic assay based on decrease of anodic oxidation current of hydrogen peroxide and widely used radical scavenge against the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH). Strong correlation has been obtained between both AO assays and total phenolic content. In addition, some individual phenolic compounds present in raspberry have been assessed using DPPH and DC polarographic assay. Comparison and evaluation of drying methods has been based on preservation of AO activity and total phenolic content. Obtained results confirmed superiority of freeze‐drying; convective drying caused slight changes while osmotic dehydration showed a significant decrease of phenolic compounds and AO activity.

Practical Application:  Optimization of drying process could be based on surveying of AO activity.
Detection of Melamine and Cyanuric Acid in Vegetable Protein Products Used in Food Production
Authors: Levinson Lawrence R. , Gilbride Kimberley A.
Published: April 2011

Abstract:  The multitude of food recalls in 2007 clearly demonstrated that total nitrogen‐content (ΣN) determination by means of near‐infrared spectroscopy (NIRS) and Kjeldahl‐based measurements can be deceived, and should no longer be regarded as a complete quality assurance program for nutritive‐protein evaluations. Furthermore, contemporary Canadian‐employed analytical tools are precariously limited in their ability to effectively assure a product where there is no a priori knowledge of the environmental toxin(s) involved. In light of these challenges, this study explored a number of analytical techniques used to assess and furthermore assure the quality of vegetable protein products (VPPs). Using liquid chromatography with tandem mass spectrometry (LC/MS/MS) technologies, a combination of VPP‐based samples was analyzed for the presence of nitrogen‐bearing environmental toxicants. Of the 52 samples tested, involving an assortment of matrices, melamine and cyanuric acid were positively identified (>1 ng/mL) in 22 and 17 samples, respectively. Subsequent high pressure liquid chromatography with ultraviolet/visible (HPLC‐UV) amino acid profiling further confirmed the adulteration of those materials contaminated with melamine and melamine‐related compounds. Based on the evidence presented herein, LC/MS/MS in combination with HPLC‐UV provides for a reliable food safety detection system as applied to VPPs. Moreover, HPLC‐UV is indispensable as a stand‐alone 1st level of screening to assess the integrity of a VPP or any nutritive protein‐based sample.

Practical Application:  Based on the evidence presented herein, LC/MS/MS in combination with HPLC‐UV can provide a reliable food safety monitoring program as applied to VPPs. HPLC‐UV is indispensable as a stand‐alone 1st level of screening to assess the integrity of a VPP or any nutritive protein‐based sample. Future research and development is required to bring the associated instrumentation costs down to a level where they can be adopted on a widespread basis.
Comparative Study of Phenolic Compounds and Antioxidant Activity in Different Species of Cherries
Authors: Liu Yun , Liu Xinyan , Zhong Fei , Tian Rongrong , Zhang Kaichun , Zhang Xiaoming , Li Tianhong
Published: April 2011

Abstract:  A new spectrometric method ultra performance liquid chromatography‐tandem mass spectrometric with high precision and rapid analysis was developed to separate 17 phenolic compounds. Different species of cherries, including 10 sweet cherry (Prunus avium L.) cultivars, a tart cherry (P. cerasus L.) rootstock (CAB), and a hybrid rootstock ‘Colt’ (P. avium × P. pseudocerasus), were analyzed for phenolics contents by this method. The results showed that significant differences were observed among the phenolic compound contents in different cherry species. In 10 sweet cherry cultivars, the contents of neochlorogenic acid and cyanidin‐3O‐rutinoside were much higher in red‐colored fruits (for example, 64.60 and 44.50 mg/100 g fresh weight in Burlat, respectively) than those in bicolored ones. Principal component analysis revealed that cyanidin‐3O‐rutinoside was an effective index for grouping the cultivars with similar species and fruit colors. Moreover, there were strong positive correlations between phenolics content and antioxidant activity, which was higher in red‐colored cherries.
Yield and Quality Effects of Electroplasmolysis and Microwave Applications on Carrot Juice Production and Storage
Authors: Rayman Ahsen , Baysal Taner
Published: April 2011

Abstract:  Electroplasmolysis as a pretreatment and microwave heating as an alternative to traditional heating were used in carrot juice production and the effects of these electrical methods on juice quality were investigated. Electroplasmolysis and microwave applications were optimized by response surface methodology. Optimum conditions were these: voltage gradient of 22.2 V/cm and treatment time of 60 s for electroplasmolysis, and flow rate of 90 mL/min with power of 900 W for microwave heating. Production of carrot juice was carried out by using these optimum conditions. After production, carrot juice samples were stored for 4 mo at +4 °C and analyses were performed at monthly intervals. As a result of electroplasmolysis, a 9.7% increase in juice yield was obtained. In addition, 100% pectin methylesterase inactivation was found with the microwave heating application. The results showed that the highest values for quality characteristics, such as antioxidant capacity and total pectin, total phenolic, and total carotenoid contents, were obtained with the combined applications of the electrical methods. In addition, these quality characteristics were protected better in the group of combined applications of the electrical methods (electroplasmolysis + microwave) during storage.

Practical Application:  Yield increase is a major objective in fruit and vegetable juice production. This study concluded that electroplasmolysis provided an increase in yield and also improved quality characteristics. Microwave heating was used as an alternative to traditional pasteurization. Applications can be adapted to production lines in industry.
A PID Type Constraint Stabilization Method for Numerical Integration of Multibody Systems
Authors: Lin Shih-Tin , Chen Ming-Wen
Published: April 2011

The dynamic equations of motion of the constrained multibody mechanical system are mixed differential-algebraic equations (DAEs). The numerical solution of the DAE systems solved using ordinary-differential equation (ODE) solvers may suffer from constraint drift phenomenon. To solve this problem, Baumgarte proposed a constraint stabilization method in which a position and velocity terms were added in the second derivative of the constraint equation. Baumgarte’s method is a proportional-derivative (PD) type controller design. In this paper, an Iintegrator controller is included to form a proportional-integral-derivative (PID) controller so that the steady state error of the numerical integration can be reduced. Stability analysis methods in the digital control theory are used to find out the correct choice of the coefficients for the PID controller.
Experimental Analyses of a First Generation Foil Bearing: Startup Torque and Dynamic Coefficients
Authors: Rudloff Laurent , Arghir Mihai , Bonneau Olivier , Matta Pierre
Published: April 2011

This paper presents the results of the experimental analysis of static and dynamic characteristics of a generation 1 foil bearing of 38.1 mm diameter and L/D=1. The test rig is of floating bearing type, the rigid shaft being mounted on ceramic ball bearings and driven up to 40 krpm. Two different casings are used for startup and for measurement of dynamic coefficients. In its first configuration, the test rig is designed to measure the startup torque. The foil bearing casing is made of two rings separated by a needle bearing to enable an almost torque free rotation between the foil bearing and the static load. The basic results are the startup torque and the lift-off speed. In its second configuration, a different casing is used to measure the impedances of the foil bearing. Misalignment is a problem that is minimized by using three flexible stingers connecting the foil bearing casing to the base plate of the test rig. The test rig enables the application of a static load and of the dynamic excitation on the journal bearing casing and can measure displacements, forces, and accelerations. Working conditions consisted of static loads comprised between 10 N and 50 N and rotation frequencies ranging from 260 Hz to 590 Hz. Excitation frequencies comprised between 100 Hz and 600 Hz are applied by two orthogonally mounted shakers for each working condition. Stiffness and damping coefficients are identified from the complex impedances and enable the calculation of natural frequencies. The experimental results show that the dynamic characteristics of the tested bearing have a weak dependence on the rotation speed but vary with the excitation frequency.
Validation of the Fuel Saving Potential of Downsized and Supercharged Hybrid Pneumatic Engines Using Vehicle Emulation Experiments
Authors: Dönitz Christian , Voser Christoph , Vasile Iulian , Onder Christopher , Guzzella Lino
Published: April 2011

The pneumatic hybridization of power trains is especially effective when it is combined with strong downsizing and supercharging of spark ignited engines. This paper presents measurement results obtained from such an engine. Specifically, performance measurements for all additional engine modes are shown. The pneumatic motor mode and the pneumatic pump mode are individually optimized over their whole operating range for maximum recuperation efficiency. Jointly with the conventional combustion mode and the pneumatic supercharged mode, they are implemented in one engine control system, thereby enabling the switching between all modes. A dynamometer simulates the longitudinal dynamics of two series production vehicles for the modified engine. This experimental setup, defined as emulation, is used to accurately measure the engine’s fuel consumption in the MVEG-95 and federal test procedure (FTP) drive cycles. Causal and noncausal energy management strategies are presented and used for choosing the engine mode during a drive cycle. Fuel savings of up to 35% are measured when comparing the modified engine to the vehicles’ standard engines with the same rated power. Hybrid pneumatic vehicles (HPVs) may prove to be a viable alternative to hybrid electric vehicles since fuel savings and driveability are comparable, while the added cost is expected to be substantially lower for HPVs.
Response of a Semi-Infinite Microstretch Homogeneous Isotropic Body Under Thermal Shock
Authors: Xiong Qi-Lin , Tian Xiao-Geng
Published: April 2011

In this paper, the thermoelastic problem of a semi-infinite microstretch homogeneous isotropic body is investigated in the context of different theories of generalized thermoelasticity. The surface of the semi-infinite body is subjected to a zonal time-dependent heat shock. The problem is solved by using a finite element method. The results, regarding temperature, stresses, displacements, microrotation, and microstretch, are presented graphically. Comparisons are made among the results derived from different generalized thermoelastic theories to show that the micropolar effect has a slight influence on the results while the microstretch effect has a great influence.
Homogenization of Rough Two-Dimensional Interfaces Separating Two Anisotropic Solids
Authors: Vinh Pham Chi , Tung Do Xuan
Published: April 2011

In this paper we have derived homogenized equations in explicit form of the linear elasticity theory in a two-dimensional domain with an interface highly oscillating between two straight lines, by using the homogenization method. First, the homogenized equation in the matrix form for generally anisotropic materials is obtained. Then, it is written down in the component form for specific cases when the materials are orthotropic, monoclinic with the symmetry plane at X1=0 and X2=0. Since these equations are in explicit form, they are significant in practical applications.
Influence of Local Material Properties on the Nonlinear Dynamic Behavior of an Atomic Force Microscope Probe
Authors: Huang Wei , Dick Andrew J.
Published: April 2011

In this paper, a study of the characteristics of period-doubling bifurcations in the dynamic behavior of an atomic force microscope probe for off-resonance excitation is presented. Using a three-mode approximation and excitation at two-and-a-half times the fundamental frequency, the relationship between the characteristics of the period-doubling bifurcation and the material properties is studied by using numerical simulations. Simulations are first used to successfully reproduce nonlinear response data collected experimentally by using a commercial atomic force microscope system and then to conduct a parametric study in order to examine the influence of variations in other system parameters on the relationship. These parameters are the excitation magnitude, the damping level, the cantilever stiffness, and the characteristics of the force model. Based upon the results of the parametric study, a new operation mode for obtaining localized material properties through an efficient scanning process is proposed. A preliminary scan simulation demonstrates the successful implementation of the relationship and its potential for providing localized material property information with nanoscale resolution.
pH-Dependent Gating in a FocA Formate Channel
Authors: Lü Wei , Du Juan , Wacker Tobias , Gerbig-Smentek Elke , Andrade Susana L. A. , Einsle Oliver
Published: April 2011

Transport of formate through a pentameric channel is gated by pH-dependent conformational changes.
Phonemic Diversity Supports a Serial Founder Effect Model of Language Expansion from Africa
Authors: Atkinson Quentin D.
Published: April 2011

Analysis of word sounds suggests that language originated once, in central and southern Africa.
Genomics, Biobanks, and the Trade-Secret Model
Authors: Mitchell Robert , Conley John M. , Davis Arlene M. , Cadigan R. Jean , Dobson Allison W. , Gladden Ryan Q.
Published: April 2011

An alternative to traditional informed-consent approaches to human subjects could provide flexibility and increased participation.
A Bicycle Can Be Self-Stable Without Gyroscopic or Caster Effects
Authors: Kooijman J. D. G. , Meijaard J. P. , Papadopoulos Jim M. , Ruina Andy , Schwab A. L.
Published: April 2011

A new bicycle design points to the importance of mass distribution for stability.
Sequential Synaptic Excitation and Inhibition Shape Readiness Discharge for Voluntary Behavior
Authors: Kagaya Katsushi , Takahata Masakazu
Published: April 2011

In crayfish, specific neurons produce electrical activity in synchrony with different phases of the walking pattern.
Enhanced Enantioselectivity in Excitation of Chiral Molecules by Superchiral Light
Authors: Tang Yiqiao , Cohen Adam E.
Published: April 2011

Light waves tuned to rotate more sharply than circularly polarized light can better discriminate between chiral molecules.
DNA Origami with Complex Curvatures in Three-Dimensional Space
Authors: Han Dongran , Pal Suchetan , Nangreave Jeanette , Deng Zhengtao , Liu Yan , Yan Hao
Published: April 2011

Rationally introduced crossover positions bend networks of double-helical DNA strands into complex shapes.
Interplay Between Changing Climate and Species’ Ecology Drives Macroevolutionary Dynamics
Authors: Ezard Thomas H. G. , Aze Tracy , Pearson Paul N. , Purvis Andy
Published: April 2011

Fossil records show that speciation and extinction are influenced by interaction with other species and with the environment.
Cytonemes Show Their Colors
Authors: Affolter Markus , Basler Konrad
Published: April 2011

In developing
Drosophila
, cells create extensions dedicated to specific signaling pathways.
Research Holds Up Well In Final 2011 Agreement
Authors: Mervis Jeffrey
Published: April 2011

When the dust settles on the spending bill—negotiated just an hour before the federal government would have shut down last week—scientists can breathe more easily. U.S. research agencies were largely spared from deep cuts in current spending.
A Sign of New Particles or General Restlessness?
Authors: Cho Adrian
Published: April 2011

Last week, news spread that scientists in the United States may have spotted a bit of matter unlike any seen before. But even as they contemplate the implications, physicists are taking the result with a grain of salt.
Do Jumping Genes Spawn Diversity?
Authors: Vogel Gretchen
Published: April 2011

The data are clear. Transposable elements move in developing brain cells. But the question remains: Does the brain tolerate them or take advantage of them?
Asteroid Model Shows Early Life Suffered a Billion-Year Battering
Authors: Kerr Richard A.
Published: April 2011

Geologists and planetary scientists at the Lunar and Planetary Science Conference reported evidence of a prolonged pummeling by huge asteroids several billion years ago that would have dwarfed the one that killed off the dinosaurs.
Prime Science Achieved at Asteroid
Authors: Kerr Richard A.
Published: April 2011

At the Lunar and Planetary Science Conference, Japanese researchers announced that detailed analyses of the sample the Hayabusa spacecraft returned from asteroid Itokawa have confirmed that the most common type of meteorite falls to Earth from a class of asteroids long cloaked by a mysterious discoloration.
Glutamic Acid Decarboxylase 65 and Islet Cell Antigen 512/IA-2 Autoantibodies in Relation to Human Leukocyte Antigen Class II DR and DQ Alleles and Haplotypes in Type 1 Diabetes Mellitus
Authors: Stayoussef Mouna , Benmansour Jihen , Al-Jenaidi Fayza A. , Said Hichem B. , Rayana Chiheb B. , Mahjoub Touhami , Almawi Wassim Y.
Published: April 2011

The frequencies of autoantibodies against glutamic acid decarboxylase 65 (GAD65) and islet cell antigen (ICA) 512/IA-2 (512/IA-2) are functions of the specific human leukocyte antigen (HLA) in type 1 diabetes mellitus (T1D). We investigated the association of HLA class II (DR and DQ) alleles and haplotypes with the presence of GAD and IA-2 autoantibodies in T1D. Autoantibodies were tested in 88 Tunisian T1D patients and 112 age- and gender-matched normoglycemic control subjects by enzyme immunoassay. Among T1D patients, mean anti-GAD antibody titers were higher in theDRB1*030101allele (P< 0.001), together with theDRB1*030101/DQB1*0201(P< 0.001) andDRB1*040101/DQB1*0302(P= 0.002) haplotypes, while lower anti-GAD titers were associated with theDRB1*070101(P= 0.001) andDRB1*110101(P< 0.001) alleles andDRB1*070101/DQB1*0201(P= 0.001) andDRB1*110101/DQB1*030101(P= 0.001) haplotypes. Mean anti-IA-2 antibody titers were higher in theDRB1*040101allele (P= 0.007) andDRB1*040101/DQB1*0302(P= 0.001) haplotypes but were lower in theDRB1*110101allele (P= 0.010) and theDRB1*110101(P< 0.001) andDRB1*110101/DQB1*030101(P= 0.025) haplotypes. Multinomial regression analysis confirmed the positive association ofDRB1*030101and the negative association ofDRB1*110101andDQB1*030101, along with theDRB1*070101/DQB1*0201andDRB1*110101/DQB1*030101haplotypes, with anti-GAD levels. In contrast, only theDRB1*040101/DQB1*0302haplotype was positively associated with altered anti-IA-2 titers. Increased GAD65 and IA-2 antibody positivity is differentially associated with select HLA class II alleles and haplotypes, confirming the heterogeneous nature of T1D.
Familial Spread of a Virulent Clone of Klebsiella pneumoniae Causing Primary Liver Abscess
Authors: Harada Sohei , Tateda Kazuhiro , Mitsui Hiroshi , Hattori Yusuke , Okubo Masao , Kimura Sei , Sekigawa Kenichiro , Kobayashi Katsuya , Hashimoto Naoaki , Itoyama Satoru , Nakai Tatsuro , Suzuki Takeo , Ishii Yoshikazu , Yamaguchi Keizo
Published: April 2011

Capsule-forming
Klebsiella pneumoniae
K1 caused primary liver abscess in two household members of a family. The causative isolates had identical pulsed-field gel electrophoresis patterns and were determined to be sequence type 23. An additional member of the family was found to carry the same strain without clinical manifestation.
First Molecular Identification and Phylogeny of a Babesia sp. from a Symptomatic Sow (Sus scrofa Linnaeus 1758)
Authors: Zobba Rosanna , Parpaglia Maria Luisa Pinna , Spezzigu Antonio , Pittau Marco , Alberti Alberto
Published: April 2011

Porcine babesiosis is a widespread yet overlooked disease causing economic losses in many regions of the world. To date, the etiological agent of porcine babesiosis has not been molecularly characterized. Here, we provide the first molecular characterization of a piroplasm detected in a symptomatic sow, phylogenetically closely related to the Ungulibabesids. Results pave the way for future molecular epidemiology studies.
Detection of Intermediately Vancomycin-Susceptible and Heterogeneous Staphylococcus aureus Isolates: Comparison of Etest and Agar Screening Methods
Authors: Riederer K. , Shemes S. , Chase P. , Musta A. , Mar A. , Khatib R.
Published: April 2011

Detection of
Staphylococcus aureus
isolates with intermediate vancomycin susceptibility (VISA) and heteroresistance (hVISA) remains problematic. The population analysis profile/area under the curve (PAP/AUC) is the gold standard but is cumbersome. We compared the performance of two Etest screening methods (macromethod [MAC] and glycopeptide resistance detection [GRD]) plus brain heart infusion (BHI) agars supplemented with 3 (BHI-V3) or 4 (BHI-V4) mg/liter vancomycin in detecting hVISA and/or VISA phenotypes. Etest hVISA screenings were done in parallel for 485 saved methicillin-resistant
S. aureus
(MRSA) blood isolates according to the manufacturer's instructions. The PAP/AUC was measured for all isolates according to the modified method. PAP/AUC test isolate/Mu3 ratios of <0.9, 0.9 to 1.3, and >1.3 were considered positive for susceptible MRSA (S-MRSA), hVISA, and VISA, respectively. PAP/AUC revealed seven VISA and 33 hVISA phenotypes. MAC screening was positive for 30 (75.0%) hVISA/VISA and 49 (11.0%) S-MRSA isolates. GRD screening was positive for 28 (70.0%) hVISA/VISA and 63 (14.2%) S-MRSA isolates. Growth on BHI-V3 was noted in all hVISA/VISA and 24 (5.4%) S-MRSA isolates. Growth on BHI-V4 was noted in all VISA and four (12.1%) hVISA isolates. None of the S-MRSA isolates grew on BHI-V4 agar. The sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were 75.0%, 89.0%, 38.0%, and 97.5% for MAC; 70.0%, 85.8%, 30.8%, and 97.0% for GRD; 100%, 94.6%, 62.5%, and 100% for BHI-V3; and 100, 99.2%, 63.6%, and 100% for BHI-V4 (for detecting VISA). These findings suggest that both Etest screening methods have excellent NPV, but positive results require confirmation. BHI-V3 and BHI-V4 agars provide more precise identification of hVISA and VISA, respectively; they may be reasonable alternatives to PAP/AUC.
Added Value of an Oropharyngeal Swab in Detection of Viruses in Children Hospitalized with Lower Respiratory Tract Infection
Authors: Hammitt Laura L. , Kazungu Sidi , Welch Steve , Bett Anne , Onyango Clayton O. , Gunson Rory N. , Scott J. Anthony G. , Nokes D. James
Published: April 2011

Paired nasopharyngeal and oropharyngeal swabs collected from 533 children hospitalized with lower respiratory tract infection were assessed by multiplex reverse transcription-PCR. Oropharyngeal swabs increased the number of viral infections detected by 15%, compared to collection of a nasopharyngeal swab alone. This advantage was most pronounced for detection of influenza, parainfluenza, and adenovirus.
Gammaherpesvirus 68 Infection of Endothelial Cells Requires both Host Autophagy Genes and Viral Oncogenes for Optimal Survival and Persistence
Authors: Suárez Andrea Luísa , Kong Raymond , George Tad , He Liqiang , Yue Zhenyu , van Dyk Linda Faye
Published: April 2011

Gammaherpesvirus-associated neoplasms include tumors of lymphocytes, epithelial cells, and endothelial cells (ECs). We previously showed that, unlike most cell types, ECs survive productive gammaherpesvirus 68 (γHV68) infection and achieve anchorage-independent growth, providing a cellular reservoir for viral persistence. Here, we demonstrated autophagy in infected ECs by analysis of LC3 localization and protein modification and that infected ECs progress through the autophagosome pathway by LC3 dual fluorescence and p62 analysis. We demonstrate that pharmacologic autophagy induction results in increased survival of infected ECs and, conversely, that autophagy inhibition results in death of infected EC survivors. Furthermore, we identified two viral oncogenes, v-cyclin and v-Bcl2, that are critical to EC survival and that modify EC proliferation and survival during infection-induced autophagy. We found that these viral oncogenes can also facilitate survival of substrate detachment in the absence of viral infection. Autophagy affords cells the opportunity to recover from stressful conditions, and consistent with this, the altered phenotype of surviving infected ECs was reversible. Finally, we demonstrated that knockdown of critical autophagy genes completely abrogated EC survival. This study reveals a viral mechanism which usurps the autophagic machinery to promote viral persistence within nonadherent ECs, with the potential for recovery of infected ECs at a distant site upon disruption of virus replication.
Immunization with Recombinant HLA Classes I and II, HIV-1 gp140, and SIV p27 Elicits Protection against Heterologous SHIV Infection in Rhesus Macaques
Authors: Mörner Andreas , Jansson Marianne , Bunnik Evelien M. , Schøller Jørgen , Vaughan Robert , Wang Yufei , Montefiori David C. , Otting Nel , Bontrop Ronald , Bergmeier Lesley A. , Singh Mahavir , Wyatt Richard T. , Schuitemaker Hanneke , Biberfeld Gunnel , Thorstensson Rigmor , Lehner Thomas
Published: April 2011

Major histocompatibility complex (MHC) molecules expressed on the surface of human immunodeficiency virus (HIV) are potential targets for neutralizing antibodies. Since MHC molecules are polymorphic, nonself MHC can also be immunogenic. We have used combinations of novel recombinant HLA class I and II and HIV/simian immunodeficiency virus (SIV) antigens, all linked to dextran, to investigate whether they can elicit protective immunity against heterologous simian/human immunodeficiency virus (SHIV) challenge in rhesus macaques. Three groups of animals were immunized with HLA (group 1,
n
= 8), trimeric YU2 HIV type 1 (HIV-1) gp140 and SIV p27 (HIV/SIV antigens; group 2,
n
= 8), or HLA plus HIV/SIV antigens (group 3,
n
= 8), all with Hsp70 and TiterMax Gold adjuvant. Another group (group 4,
n
= 6) received the same vaccine as group 3 without TiterMax Gold. Two of eight macaques in group 3 were completely protected against intravenous challenge with 18 50% animal infective doses (AID
50
) of SHIV-SF162P4/C grown in human cells expressing HLA class I and II lineages represented in the vaccine, while the remaining six macaques showed decreased viral loads compared to those in unimmunized animals. Complement-dependent neutralizing activity in serum and high levels of anti-HLA antibodies were elicited in groups 1 and 3, and both were inversely correlated with the plasma viral load at 2 weeks postchallenge. Antibody-mediated protection was strongly supported by the fact that transfer of pooled serum from the two challenged but uninfected animals protected two naïve animals against repeated low-dose challenge with the same SHIV stock. This study demonstrates that immunization with recombinant HLA in combination with HIV-1 antigens might be developed into an alternative strategy for a future AIDS vaccine.
Enhancement of Replication of RNA Viruses by ADAR1 via RNA Editing and Inhibition of RNA-Activated Protein Kinase
Authors: Gélinas Jean-François , Clerzius Guerline , Shaw Eileen , Gatignol Anne
Published: April 2011

Adenosine deaminase acting on RNA 1 (ADAR1) is a double-stranded RNA binding protein and RNA-editing enzyme that modifies cellular and viral RNAs, including coding and noncoding RNAs. This interferon (IFN)-induced protein was expected to have an antiviral role, but recent studies have demonstrated that it promotes the replication of many RNA viruses. The data from these experiments show that ADAR1 directly enhances replication of hepatitis delta virus, human immunodeficiency virus type 1, vesicular stomatitis virus, and measles virus. The proviral activity of ADAR1 occurs through two mechanisms: RNA editing and inhibition of RNA-activated protein kinase (PKR). While these pathways have been found independently, the two mechanisms can act in concert to increase viral replication and contribute to viral pathogenesis. This novel type of proviral regulation by an IFN-induced protein, combined with some antiviral effects of hyperediting, sheds new light on the importance of ADAR1 during viral infection and transforms our overall understanding of the innate immune response.
Genome-Wide Analysis of the 5′ and 3′ Ends of Vaccinia Virus Early mRNAs Delineates Regulatory Sequences of Annotated and Anomalous Transcripts
Authors: Yang Zhilong , Bruno Daniel P. , Martens Craig A. , Porcella Stephen F. , Moss Bernard
Published: April 2011

Poxviruses are large DNA viruses that encode a multisubunit RNA polymerase, stage-specific transcription factors, and enzymes that cap and polyadenylate mRNAs within the cytoplasm of infected animal cells. Genome-wide microarray and RNA-seq technologies have been used to profile the transcriptome of vaccinia virus (VACV), the prototype member of the family. Here, we adapted tag-based methods in conjunction with SOLiD and Illumina deep sequencing platforms to determine the precise 5′ and 3′ ends of VACV early mRNAs and map the putative transcription start sites (TSSs) and polyadenylation sites (PASs). Individual and clustered TSSs were found preceding 104 annotated open reading frames (ORFs), excluding pseudogenes. In the majority of cases, a 15-nucleotide consensus core motif was present upstream of the ORF. This motif, however, was also present at numerous other locations, indicating that it was insufficient for transcription initiation. Further analysis revealed a 10-nucleotide AT-rich spacer following functional core motifs that may facilitate DNA unwinding. Additional putative TSSs occurred in anomalous locations that may expand the functional repertoire of the VACV genome. However, many of the anomalous TSSs lacked an upstream core motif, raising the possibility that they arose by a processing mechanism as has been proposed for eukaryotic systems. Discrete and clustered PASs occurred about 40 nucleotides after an UUUUUNU termination signal. However, a large number of PASs were not preceded by this motif, suggesting alternative polyadenylation mechanisms. Pyrimidine-rich coding strand sequences were found immediately upstream of both types of PASs, signifying an additional feature of VACV 3′-end formation and polyadenylation.
Vesicular Stomatitis Virus-Simian Retrovirus Type 2 Vaccine Protects Macaques from Detectable Infection and B-Cell Destruction
Authors: Gautam Rajeev , Iyer Arun , Hunter Meredith , Das Arpita , Williams Tessa , Dufour Jason , Apetrei Cristian , Kousoulas K. Gus , Marx Preston A.
Published: April 2011

Natural infection with simian retrovirus (SRV) has long been recognized in rhesus macaques (RMs) and may result in an AIDS-like disease. Importantly, SRV infections persist as a problem in recently imported macaques. Therefore, there is a clear need to control SRV spread in macaque colonies. We developed a recombinant vesicular stomatitis virus (VSV)-SRV vaccine consisting of replication-competent hybrid VSVs that express SRV
gag
and
env
in separate vectors. The goal of this study was to assess the immunogenicity and protective efficacy of the VSV-SRV serotype 2 vaccine prime-boost approach in RMs. The VSV-SRV vector (expressing either SRV
gag
or
env
) vaccines were intranasally administered in 4 RMs, followed by a boost 1 month after the first vaccination. Four RMs served as controls and received the VSV vector alone. Two months after the boost, all animals were intravenously challenged with SRV-2 and monitored for 90 days. After the SRV-2 challenge, all four controls became infected, and viral loads (VLs) ranged from 10
6
to 10
8
SRV RNA copies/ml of plasma. Two animals in the control group developed simian AIDS within 7 to 8 weeks postinfection and were euthanized. Anemia and weight loss were observed in the remaining controls. During acute infection, severe B-cell depletion and no significant changes in T-cell population were observed in the control group. Control RMs with greater preservation of B cells and lower VLs survived longer. SRV-2 was undetectable in vaccinated animals, which remained healthy, with no clinical or biological signs of infection and preservation of B cells. Our study showed that the VSV-SRV vaccine is a strong approach for preventing clinically relevant type D retrovirus infection and disease in RMs, with protection of 4/4 RMs from SRV infection and prevention of B-cell destruction. B-cell protection was the strongest correlate of the long-term survival of all vaccinated and control RMs.
The introduction of a double bond on the steroid skeleton – The preparation of enol silyl ether derivatives from vicinal diols
Authors: Marek Aleš , Klepetářová Blanka , Elbert Tomáš
Published: April 2011

The ways of converting steroid vicinal diol into an unsaturated derivative were studied with the intention of preparing suitable precursors for the introduction of deuterium or tritium into the molecules of brassinosteroids. The model vicinal diol compound, 2α,3α-dihydroxy-5α-pregnane-6,20-dione (3), was converted with high regioselectivity to the α-hydroxy ketone derivative, 2α-hydroxy-5α-pregnane-3,6,20-trione (8), in a 75% yield. The attempts to convert α-hydroxy ketone 8 to the dioxolene derivative, 2α,3α-(isopropylidenedioxy)-5α-pregn-2-ene-6,20-dione (6), failed. The conditions for the conversion of ketone to the corresponding enol trialkylsilyl ether were optimized using cyclohexanone as a model compound. The best and reproducible results were obtained by using tert-butyldimethylsilyl trifluoromethansulfonate (TBDMSiOTf) as the silylating reagent and triethylamine as the base. Under these conditions, the 3,6,20-trione (8) was converted to 2,3-bis(tert-butyldimethylsilyloxy)-5α-pregn-2-ene-6,20-dione (14) with a 66% yield.
Dynamic quadriceps angle: a comparison of female elite volleyball players with and without patellofemoral pain syndrome
Authors: Massada M , Aido R , Magalhães C , Puga N
Published: April 2011

Background

Patellofemoral pain syndrome (PFPS) is the most common complaint in female volleyball players. Larger quadriceps femoris angle (Q angle) has been implicated as a source of patellofemoral pain but values measured during functional tasks (dynamic Q angle) have not been adequately documented in the literature.

Objective

With this study, we attempt to determine whether excessive Q angle during a functional task is related with PFPS.

Design

A correlational study.

Setting

The study was conducted among high performance female athletes all participating in the Portuguese A1 Division.

Participants

50 female volleyball players participated. They were included in one of two groups, according to the presence or absence of patellofemoral pain.

Interventions

Static Q angle was measured using a goniometer. Subjects were videotaped during the execution of simple functional tasks and dynamic Q angle was determined ‘a posteriori’ using a video analysis program.

Main outcome measurements

A correlation was examined between static and dynamic Q angle and the prevalence of patellofemoral pain.

Results

When averaged across all conditions, the average dynamic Q-angle was significantly higher in the PFP group compared to the control group (34.9° vs 22.3°). We found a relationship between larger dynamic Q angles and PFPS (r=-0.517) that remained significant (p<0.01) when the static Q angle was normal.

Conclusions

The results substantiate the belief that lower extremity motion during dynamic tasks may increase Q-angle and the lateral force acting on the patella, even on individuals with a ‘normal’ static Q-angle. Static Q-angle measurements in this study showed little relationship to dynamic Q-angle measurements and with the presence of PFP.
Concentric and eccentric strength profile of quadriceps and hamstrings in healthy volleyball players
Authors: Hadzic V , Dervisevic E , Veselko M
Published: April 2011

Background

Lower-extremity strength profile can be used in injury prevention, conditioning and rehabilitation of volleyball players.

Objectives

The goals were: (1) to describe the concentric and eccentric quadriceps (Q) and hamstrings (H) muscle function in volleyball players, (2) to evaluate the differences in Q and H strength, strength ratios and bilateral strength asymmetry among age groups, playing positions and playing levels, (3) to compare bilateral strength asymmetry in Q and H muscles in two different contraction modes.

Design

Controlled laboratory study.

Setting

Competitive elite level.

Participants and intervention

95 professional male volleyball players were tested on an isokinetic machine at 60°/sec to assess concentric and eccentric Q and H strength. We also calculated strength ratios and bilateral strength asymmetries.

Results

Multivariate analysis of variances indicated significant main effect of playing level on relative PT (p=0.001) and strength ratios (p<0.05). International-level players had significantly (p<0.05) higher H strength and dynamic control ratio (DCR) of the right leg compared to the first and/or second national division players. There were no signs of bilateral strength asymmetry regardless of muscle group tested and contraction mode.

Conclusions

Our results suggest that right H strength and DCR could be important for successful volleyball performance. Descriptive data about Q and H muscle function can be used as guidelines for coaches and therapists during training and rehabilitation of male volleyball players.
Respiratory parameters of elite national water polo and volleyball players
Authors: Plavsic J , Djordjevic-Saranovic S , Gavrilovic T , Zlatkovic J , Mazic S
Published: April 2011

Background

The differences in respiratory parameters among young athletes could be influenced by biological development itself or they could appear under the impact of the training stimulus that is characteristic for a certain type of sport.

Objective

The aim of this study was to show the differences in respiratory parameters (FVC (L), FEV1 (L), PEF (L/s), MVV (L/min), VE (L/min), Vmax-25 (L/s), Vmax-50 (L/s), Vmax-75 (L/s), VT (L)) between the two groups of elite national water polo and volleyball teams.

Setting and participants

This research included 32 mail professional players divided in two groups, water polo (n1=15, age 25.95±3.60 years old, body height 192.70±3.76 cm, body weight 100.80±5.84 kg) and volleyball (n2=17, age 24.53±3.80 years old, body height 198.44±4.97 cm, body weigh 91.47±9.84 kg). The research was conducted in the laboratory for functional diagnostic in the National Institute of Sport in Belgrade.

Methods

Measurement of respiratory parameters was performed using a Cosmed spyrometer Pony graphic.

Results

By applying the T test on two small independent samples we didn't notice statistically significance difference in respiratory parameters between elite national water polo and volleyball teams. On the level of statistic significance p<0.001 we spotted a difference in body height (water polo 192.70±3.76 cm vs volleyball 198.44±4.97 cm) and body weight (water polo 100.80±5.84 kg vs volleyball 91.41±9.84 kg).

Conclusions

We observed no significant differences in static and dynamic respiratory parameters among the participating senior water polo and volleyball players. We conclude that after complete biological development, it is not possible to influence most respiratory parameters studied.
Time analysis of men's and youth boy's top-level volleyball
Authors: Häyrinen M , Lehto H , Mikkola T , Honkanen P , Lahtinen P , Paananen A , Blomqvist M
Published: April 2011

Background

Some time analysis studies in men's top-level volleyball have been reported, but no studies exist from the youth boy's top-level. The purpose of this study was to conduct a time analysis in men's and youth boy's top-level volleyball to update the current data and to compare the results between men and boys.

Design, setting, and methods

Four men's matches (finals and semi-finals of the 2008 Olympic Games, OG08) and four youth boy's matches (finals and semi-finals of the 2009 Youth U19 Boy's European Championships, YEC09) were analyzed using Dartfish TeamPro 5.5 -software. The duration of the rallies, sets (no fifth sets), breaks between rallies (no time outs or breaks between sets) and sets were analyzed. The accuracy of the time analysis was 0.04 s. The t test for independent samples was used to compare the results between the groups.

Results

The duration of the rallies in OG08 and YEC09 was 5.45±4.77 s and 5.76±4.40 s (ns), the number of rallies per set 45.3±5.1 and 44.0±6.7 (ns), the duration of the breaks between rallies 23.54±5.55 s and 19.99±5.70 s (p<0.001), the duration of the sets 1582±133 s and 1412±143 s (p<0.01) and the duration of the breaks between sets 217±17 s and 213±20 s (ns), respectively.

Conclusions

The duration of the rallies in men's matches was very close to the previously presented values. The number of rallies per set has constantly been around 45 in the Olympic matches in the 21st century. The duration of the breaks between rallies on the other hand has increased and thus the total length of the sets has increased approximately 4 min. In the boy's matches the duration of the breaks between rallies was significantly shorter than in the men's matches and thus also the total duration of the sets was shorter.
Level of play related anthropometric differences in volleyball players
Authors: Zadraznik M , Dervisevic E
Published: April 2011

Background

Volleyball is a sport where anthropometric measures strongly influence the level of play.

Objective

The aim of our study was to explore the differences in the anthropometric measures in volleyball players among different levels of play.

Design

Controlled laboratory study.

Setting

Elite national division (competitive).

Participants and methods

301 volleyball player (115 males and 134 females) underwent the anthropometric testing at the Faculty of sport in Ljubljana at the end of competitive season 2006–2007. Players were recruited from Slovenian 1st (49 males, 66 females) and 2nd league (66 males, 68 females). Testing included body height, body mass and 9-site skinfold measurements. Later on body mass index and body composition (percentage fat, lean body mass, somatotyping …) was calculated. Multivariate analysis of variance with correction for age was used to evaluate the differences among different levels of play.

Results

On multivariate level the differences among the 1st and 2nd division existed in both sexes (males F=4.41, p=0.0001; females F=2.84, p=0.004). On univariate level the main differences in both sexes were related to the body height (males F=10.92, p=0.01; females 10.20, p=0.002) and lean body mass (males F=14.96, p=0.0002; females 8.13, p=0.005), while in males the differences existed in the bone mass as well (F=4.21, p=0.04).

Conclusions

Our results suggest that body height remains the important factor of success in volleyball players. While the body height is genetically determined and virtually impossible to modify, the lean body mass is the modifiable factor that should be regularly monitored and adjusted in volleyball players. Our study offers solid reference values for the anthropometric evaluation of volleyball players.
Biomechanical analysis of the jump serve in men's volleyball
Authors: Häyrinen M , Mikkola T , Honkanen P , Lahtinen P , Paananen A , Blomqvist M
Published: April 2011

Background

The most used serve technique in men's top volleyball is jump serve (JS). The efficiency of JS is related to the ball velocity (BV) of the serve. BVs have increased lately and thus a biomechanical analysis of JS was justified to investigate which elements have the biggest influence to BV of JS.

Setting and participants

Six players of the Finnish men's national volleyball team (23.40±2.28 years, 196.50±1.52 cm, 90.67±1.63 kg) served as subjects.

Methods

3D-motion analysis (100 Hz) was made from two of the each player's JSs (the fastest (FS) and one slower serve (SS)). T test for paired samples was used to compare the velocities of FS and SS. Analysis of variance was applied to compare JSs in which the velocity was over 30 m/s (+30S) and under 30 m/s (−30S). The relationships between motion analysis variables and BV in all JSs were examined using Pearson's correlation coefficient.

Results

The most essential variables in which statistically significant differences between FS and SS and velocities +30S and −30S were found were: the position of the ball and the centre of gravity of the body at the time of the ball contact, the minimum angle and the maximal angle velocity of the thigh-trunk joint, the maximal forward velocities of the shoulder, elbow and wrist joints of the hitting hand and forward velocities of the elbow and wrist joints and middle finger at the time of the ball contact. The same variables correlated significantly with BV.

Conclusions

These findings suggest that in JS a successful throw is crucial in achieving higher BVs. Furthermore good power production abilities in the core, shoulder and arm and optimal function of the kinetic chain are important elements. The mobility of the hip joint and the thoracic vertebrae are also important factors in achieving high BVs.
Off-balance dorsal position at volleyball service involved in sciatic nerve inflammation
Authors: Ntolopoulou M S
Published: April 2011

Objective

The aim of the study is to demonstrate that wrong physical position in volleyball service hit is associated with sciatic nerve injuries sustained by young female athletes.

Design

Observational study through the Dartfish framework video analysis of biomechanical movement.

Setting

Personal study.

Participants

Young female (aged 16–18) volleyball players(N=20) from a single country public school district trained at high-level competition in school and in youth teams were recruited to participate in biomechanical video analysis combined with a study of their pathological minor injuries medical record.

Intervention

Prevention through use of video analysis of sciatic nerve minor injuries caused by frequent repetition of wrong service position/movement.

Results

Young female athletes' long-term exposure to biomechanically wrong position of trunk and, more particularly, of ankle-knee-hip axis in young female athletes in the course of holding the ball and delivering the service hit accounts for pathological sciatic nerve minor injuries (painful inflammations).

Conclusions

In preventing sciatic nerve minor injuries a major role is played by a knowledgeable trainer insisting on biomechanically proper service position to be adopted at the earliest age in combination with a set of exercises aimed at dorsal musculature build-up. Practice aimed at mastering the perfect movement/position is essential right from the start of female volleyball players' training at the age of 12.