bluuebunny/crossref_metadata_2025 huggingface dataset:
Insight into the assembly mechanism in the supramolecular rings of the sodium-driven
Vibrio
flagellar motor from the structure of FlgT
Authors: Terashima Hiroyuki , Li Na , Sakuma Mayuko , Koike Masafumi , Kojima Seiji , Homma Michio , Imada Katsumi
Published: March 2013

Flagellar motility is a key factor for bacterial survival and growth in fluctuating environments. The polar flagellum of a marine bacterium,
Vibrio alginolyticus
, is driven by sodium ion influx and rotates approximately six times faster than the proton-driven motor of
Escherichia coli
. The basal body of the sodium motor has two unique ring structures, the T ring and the H ring. These structures are essential for proper assembly of the stator unit into the basal body and to stabilize the motor. FlgT, which is a flagellar protein specific for
Vibrio
sp., is required to form and stabilize both ring structures. Here, we report the crystal structure of FlgT at 2.0-Å resolution. FlgT is composed of three domains, the N-terminal domain (FlgT-N), the middle domain (FlgT-M), and the C-terminal domain (FlgT-C). FlgT-M is similar to the N-terminal domain of TolB, and FlgT-C resembles the N-terminal domain of FliI and the α/β subunits of F
1
-ATPase. To elucidate the role of each domain, we prepared domain deletion mutants of FlgT and analyzed their effects on the basal-body ring formation. The results suggest that FlgT-N contributes to the construction of the H-ring structure, and FlgT-M mediates the T-ring association on the LP ring. FlgT-C is not essential but stabilizes the H-ring structure. On the basis of these results, we propose an assembly mechanism for the basal-body rings and the stator units of the sodium-driven flagellar motor.
Interchangeable adaptors regulate mitochondrial dynamin assembly for membrane scission
Authors: Koirala Sajjan , Guo Qian , Kalia Raghav , Bui Huyen T. , Eckert Debra M. , Frost Adam , Shaw Janet M.
Published: March 2013

Significance

Mitochondrial fission is critical for mammalian cell division, mitophagy, and development. Fission initiates via recruitment of dynamin-related GTPases to the mitochondrial surface. In yeast and human, the recruitment utilizes adaptors that differ in sequence and predicted structure. Key unresolved issues are whether these adaptors function independently in membrane recruitment and whether a single adaptor and GTPase are sufficient to catalyze scission. We show that three human adaptors work interchangeably with a single mitochondrial dynamin to accomplish fission. We also show that an adaptor alters the architecture of the dynamin polymer in a manner that could facilitate membrane constriction and severing.
In vitro and in vivo delivery of genes and proteins using the bacteriophage T4 DNA packaging machine
Authors: Tao Pan , Mahalingam Marthandan , Marasa Bernard S. , Zhang Zhihong , Chopra Ashok K. , Rao Venigalla B.
Published: March 2013

The bacteriophage T4 DNA packaging machine consists of a molecular motor assembled at the portal vertex of an icosahedral head. The ATP-powered motor packages the 56-µm-long, 170-kb viral genome into 120 nm × 86 nm head to near crystalline density. We engineered this machine to deliver genes and proteins into mammalian cells. DNA molecules were translocated into emptied phage head and its outer surface was decorated with proteins fused to outer capsid proteins, highly antigenic outer capsid protein (Hoc) and small outer capsid protein (Soc). T4 nanoparticles carrying reporter genes, vaccine candidates, functional enzymes, and targeting ligands were efficiently delivered into cells or targeted to antigen-presenting dendritic cells, and the delivered genes were abundantly expressed in vitro and in vivo. Mice delivered with a single dose of F1-V plague vaccine containing both gene and protein in the T4 head elicited robust antibody and cellular immune responses. This “progene delivery” approach might lead to new types of vaccines and genetic therapies.
Parkinson-susceptibility gene DJ-1/PARK7 protects the murine heart from oxidative damage in vivo
Authors: Billia Filio , Hauck Ludger , Grothe Daniela , Konecny Filip , Rao Vivek , Kim Raymond H. , Mak Tak W.
Published: March 2013

Oxidative stress is caused by an imbalance between the production of reactive oxygen species (ROS) and the ability of an organism to eliminate these toxic intermediates. Although the Parkinson-susceptibility gene, Parkinson protein 7/DJ-1 (DJ-1), has been linked to the regulation of oxidative stress, the exact mechanism by which this occurs and its in vivo relevance have remained elusive. In the heart, oxidative stress is a major contributor to the development of heart failure (HF). Therefore, we hypothesized that DJ-1 inhibits the pathological consequences of ROS production in the heart, the organ with the highest oxidative burden. We report that DJ-1 is highly expressed in normal heart tissue but is markedly reduced in end-stage human HF. DJ-1-deficient mice subjected to oxidative stress by transaortic banding exhibited exaggerated cardiac hypertrophy and susceptibility to developing HF. This was accompanied by a Trp53 (p53)-dependent decrease in capillary density, an excessive oxidation of DNA, and increased cardiomyocyte apoptosis, key events in the development of HF. Impaired mitochondrial biogenesis and progressive respiratory chain deficiency were also evident in cardiomyocytes lacking DJ-1. Our results provide compelling in vivo evidence that DJ-1 is a unique and nonredundant antioxidant that functions independent of other antioxidative pathways in the cellular defense against ROS.
Spatial Transposition Gradients in Visual Working Memory
Authors: Rerko Laura , Oberauer Klaus , Lin Hsuan-Yu
Published: March 2013

In list memory, access to individual items reflects limits of temporal distinctiveness. This is reflected in the finding that neighbouring list items tend to be confused most often. This article investigates the analogous effect of spatial proximity in a visual working-memory task. Items were presented in different locations varying in spatial distance. A retro-cue indicated the location of the item relevant for the subsequent memory test. In two recognition experiments, probes matching spatially close neighbours of the relevant item led to more false alarms than probes matching distant neighbours or non-neighbouring memory items. In two probed-recall experiments, one with simultaneous, the other with sequential memory item presentation, items closer to the cued location were more frequently chosen for recall than more distant items. These results reflect a spatial transposition gradient analogous to the temporal transposition gradient in serial recall and challenge fixed-capacity models of visual working memory (WM).
Rise and fall of the kinetochore
Authors: Leslie Mitch
Published: March 2013

Study pinpoints two ways that cells control dynamics of kinetochore proteins.
CD1c tetramers detect ex vivo T cell responses to processed phosphomycoketide antigens
Authors: Ly Dalam , Kasmar Anne G. , Cheng Tan-Yun , de Jong Annemieke , Huang Shouxiong , Roy Sobhan , Bhatt Apoorva , van Summeren Ruben P. , Altman John D. , Jacobs William R. , Adams Erin J. , Minnaard Adriaan J. , Porcelli Steven A. , Moody D. Branch
Published: March 2013

CD1c is expressed with high density on human dendritic cells (DCs) and B cells, yet its antigen presentation functions are the least well understood among CD1 family members. Using a CD1c-reactive T cell line (DN6) to complete an organism-wide survey of M. tuberculosis lipids, we identified C32 phosphomycoketide (PM) as a previously unknown molecule and a CD1c-presented antigen. CD1c binding and presentation of mycoketide antigens absolutely required the unusual, mycobacteria-specific lipid branching patterns introduced by polyketide synthase 12 (pks12). Unexpectedly, one TCR responded to diversely glycosylated and unglycosylated forms of mycoketide when presented by DCs and B cells. Yet cell-free systems showed that recognition was mediated only by the deglycosylated phosphoantigen. These studies identify antigen processing of a natural bacterial antigen in the human CD1c system, indicating that cells act on glycolipids to generate a highly simplified neoepitope composed of a sugar-free phosphate anion. Using knowledge of this processed antigen, we generated human CD1c tetramers, and demonstrate that CD1c–PM complexes stain T cell receptors (TCRs), providing direct evidence for a ternary interaction among CD1c-lipid-TCR. Furthermore, PM-loaded CD1c tetramers detect fresh human T cells from peripheral blood, demonstrating a polyclonal response to PM antigens in humans ex vivo.
RhoGEF12 controls cardiac remodeling by integrating G protein– and integrin-dependent signaling cascades
Authors: Takefuji Mikito , Krüger Marcus , Sivaraj Kishor K. , Kaibuchi Kozo , Offermanns Stefan , Wettschureck Nina
Published: March 2013

Structural cardiac remodeling, including hypertrophy and fibrosis, plays a crucial role in the pathogenesis of heart failure. In vitro studies suggested a role of the small GTPase RhoA in hypertrophic cardiomyocyte growth, but neither the molecular mechanisms leading to RhoA activation nor their relevance in vivo are known. We use here a mass spectrometric approach to identify Rho guanine nucleotide exchange factors (RhoGEFs) activated during cardiac pressure overload in vivo and show that RhoGEF12 is a central player during cardiac remodeling. We show that RhoGEF12 is required for stretch-induced RhoA activation and hypertrophic gene transcription in vitro and that its activation depends on integrin β1 and heterotrimeric G proteins of the G12/13 family. In vivo, cardiomyocyte-specific deletion of RhoGEF12 protects mice from overload-induced hypertrophy, fibrosis, and development of heart failure. Importantly, in mice with preexisting hypertrophy, induction of RhoGEF12 deficiency protects from cardiac decompensation, resulting in significantly increased long-term survival. Collectively, RhoGEF12 acts as an integrator of stretch-induced signaling cascades in cardiomyocytes and is an interesting new target for therapeutic intervention in patients with pressure overload–induced heart failure.
A Novel Xanthomonas sp. Causes Bacterial Spot of Rose (Rosa spp.)
Authors: Huang Cheng-Hua , Vallad Gary E. , Adkison Heather , Summers Carly , Margenthaler Elaina , Schneider Christina , Hong Jason , Jones Jeffrey B. , Ong Kevin , Norman David J.
Published: March 2013

A bacterial spot of rose (Rosa spp.) caused by a xanthomonad was observed in Florida and Texas. Ten representative strains collected from the two states between 2004 and 2010 were used to determine the taxonomic position of this rose pathogen. Fatty acid methyl ester analysis was performed and a nearly 2-kb 16S-23S rRNA intergenic spacer along with flanking portions of the 16S and 23S rRNA genes were sequenced for selected strains, showing that they were members of the genus Xanthomonas. Multilocus sequence typing and analysis (MLST/MLSA) and pathogenicity tests were conducted to further characterize the Xanthomonas strains. The MLSA, based on six gene fragments—fusA, gapA, gltA, gyrB, lacF, and lepA—showed that the rose strains fell into Xanthomonas axonopodis subgroup 9.2 and shared the highest similarity values (98.8 to 99.7%) with X. alfalfae subsp. citrumelonis of the subgroup. However, principal coordinate analysis grouped the rose strains into a unique cluster distinct from other members of the subgroup according to virulence phenotypes on 11 plant species belonging to five plant families (Araceae, Euphorbiaceae, Rosaceae, Rutaceae, and Solanaceae). Moreover, the rose strains were aggressive on rose and Indian Hawthorn (Rhaphiolepsis indica). On the basis of the MLSA and virulence phenotypes, the pathovar epithet rosa is proposed.
First Report of Branch Dieback of Walnut Caused by Neofusicoccum parvum in Korea
Authors: Cheon W. , Kim Y. S. , Lee S. G. , Jeon Y. H. , Chun I.-J.
Published: March 2013

Walnut (Juglans sinensis Dode) is an economically important tree in the world, both for its wood and its fruit. Walnut fruits, as rich sources of omega-3 essential fatty acid, are valuable nutritionally. Consumer interest in Korea for walnuts has increased in recent years, and production has increased to 1,042 ha with the Kyoungbuk region consisting of 402 ha (2). In May 2012, lethal dieback disease of walnut tree was detected in two orchards in Andong, Kyoungbuk region, Korea, each with an incidence of 25 to 30%. Disease symptoms included blight and dieback of the stems, flowing resin, dark decay inside the bark of dead twigs, and defoliation. The bark of dead twigs was removed and sliced thinly using a razor blade, and water-mounted, without staining, for observation of fungal structures, if present. Pycnidia were found embedded within the bark of dead twigs and conidia were mostly characterized by fusoid, hyaline, smooth, thin-walled, unicellular and 16.25 to 21.25 μm long and 4.37 to 6.87 μm wide. These characteristics are consistent with those reported previously for Neofusicoccum parvum (Pennycook & Samuels) Crous, Slippers & A.J.L. Phillips (1). Diseased branch tissues collected from the two locations were surface sterilized with 1% NaOCl, rinsed with sterile distilled water, and plated on potato dextrose agar (PDA). The fungal isolates, recovered from the two different orchards, produced white, aerial mycelium and became light gray within a week after incubating plates at 25°C. To confirm the identities of the isolates, the complete internal transcribed spacer (ITS) rDNA of the fungi was amplified and sequenced using PCR. The sequences were compared with other DNA sequences in the GenBank database, using a BLAST search. BLAST analysis of the PCR product showed that the sequence had 99% identity with the nucleotide sequences for N. parvum (JQ411396.1 and GU997688.1). Additionally, the chitin synthase 1 gene was sequenced and analyzed using the BLAST server. The sequence of PCR product had 100% identity with the nucleotide sequences of N. parvum strain CMW9080 chitin synthase 1 gene (EU339501). Thus, both morphological and molecular characters confirmed this species as N. parvum. Pathogenecity tests were performed by inoculating 2-year-old J. sinensis trees. Inoculations consisted of inserting 5-mm-diamter agar plug bearing fresh mycelium of the fungal isolates into the wounds. Within 2 weeks, black lesions appeared on all inoculated plants accompanied by defoliation, whereas no symptoms were observed in the control plants. N. parvum has been reported a member of Botryosphaeriaceae, commonly associated with dieback and cankers of woody plants (1). To our knowledge, this study is the first report of N. parvum as a pathogen of Juglans sinensis in Korea.

References: (1) P. W. Crous et al. Stud. Mycol. 55:235, 2006. (2) Statistics Korea. Forest Households by Growing Area of Walnut/Total Area. 2010.
Disease Risk Curves
Authors: Hughes G. , Burnett F. J. , Havis N. D.
Published: March 2013

Disease risk curves are simple graphical relationships between the probability of need for treatment and evidence related to risk factors. In the context of the present article, our focus is on factors related to the occurrence of disease in crops. Risk is the probability of adverse consequences; specifically in the present context it denotes the chance that disease will reach a threshold level at which crop protection measures can be justified. This article describes disease risk curves that arise when risk is modeled as a function of more than one risk factor, and when risk is modeled as a function of a single factor (specifically the level of disease at an early disease assessment). In both cases, disease risk curves serve as calibration curves that allow the accumulated evidence related to risk to be expressed on a probability scale. When risk is modeled as a function of the level of disease at an early disease assessment, the resulting disease risk curve provides a crop loss assessment model in which the downside is denominated in terms of risk rather than in terms of yield loss.
Low-frequency Neuromuscular Depression Is a Consequence of a Reduction in Nerve Terminal Ca2+ Currents at Mammalian Motor Nerve Endings
Authors: Silinsky Eugene M.
Published: March 2013

Background:

The decline in voluntary muscle contraction during low-frequency nerve stimulation is used clinically to assess the type and degree of neuromuscular block. The mechanism underlying this depression is unknown.

Methods:

Simultaneous electrophysiological measurements of neurotransmitter release and prejunctional Ca2+ currents were made at mouse neuromuscular junctions to evaluate the hypothesis that decreases in nerve terminal Ca2+ currents are responsible for low-frequency depression.

Results:

Under conditions generally used to measure Ca2+ currents at the neuromuscular junction, increasing the frequency of nerve stimulation briefly from 0.017 to 0.1–1 Hz caused a simultaneous reduction in the release of the neurotransmitter acetylcholine to 52.2 ± 4.4% of control and the Ca2+ current peak to 75.4 ± 2.0% of control (P < 0.001, n = 5 experiments for both measurements, mean ± SEM for all data). In conditions used for train-of-four monitoring (4 stimuli, 2 Hz), neurotransmitter release declined to 42.0 ± 1.0% of control and the Ca2+ current peak declined to 75.8 ± 3.3% of control between the first and fourth stimulus (P < 0.001, n = 7 experiments for both measurements). Depression in acetylcholine release during train-of-four protocols also occurred in the absence of neuromuscular-blocking drugs.

Discussion:

The results demonstrate that neuromuscular depression during train-of-four monitoring is due to a decline in nerve terminal Ca2+ currents, hence reducing the release of acetylcholine. As similar processes may come into play at higher stimulation frequencies, agents that antagonize the decline in Ca2+ currents could be used to treat conditions in which neuromuscular depression can be debilitating.
Elastin and collagen fibre microstructure of the human aorta in ageing and disease: a review
Authors: Tsamis Alkiviadis , Krawiec Jeffrey T. , Vorp David A.
Published: March 2013

Aortic disease is a significant cause of death in developed countries. The most common forms of aortic disease are aneurysm, dissection, atherosclerotic occlusion and ageing-induced stiffening. The microstructure of the aortic tissue has been studied with great interest, because alteration of the quantity and/or architecture of the connective fibres (elastin and collagen) within the aortic wall, which directly imparts elasticity and strength, can lead to the mechanical and functional changes associated with these conditions. This review article summarizes the state of the art with respect to characterization of connective fibre microstructure in the wall of the human aorta in ageing and disease, with emphasis on the ascending thoracic aorta and abdominal aorta where the most common forms of aortic disease tend to occur.
Reception and learning of electric fields in bees
Authors: Greggers Uwe , Koch Gesche , Schmidt Viola , Dürr Aron , Floriou-Servou Amalia , Piepenbrock David , Göpfert Martin C. , Menzel Randolf
Published: March 2013

Honeybees, like other insects, accumulate electric charge in flight, and when their body parts are moved or rubbed together. We report that bees emit constant and modulated electric fields when flying, landing, walking and during the waggle dance. The electric fields emitted by dancing bees consist of low- and high-frequency components. Both components induce passive antennal movements in stationary bees according to Coulomb's law. Bees learn both the constant and the modulated electric field components in the context of appetitive proboscis extension response conditioning. Using this paradigm, we identify mechanoreceptors in both joints of the antennae as sensors. Other mechanoreceptors on the bee body are potentially involved but are less sensitive. Using laser vibrometry, we show that the electrically charged flagellum is moved by constant and modulated electric fields and more strongly so if sound and electric fields interact. Recordings from axons of the Johnston organ document its sensitivity to electric field stimuli. Our analyses identify electric fields emanating from the surface charge of bees as stimuli for mechanoreceptors, and as biologically relevant stimuli, which may play a role in social communication.
Wing flexibility enhances load-lifting capacity in bumblebees
Authors: Mountcastle Andrew M. , Combes Stacey A.
Published: March 2013

The effect of wing flexibility on aerodynamic force production has emerged as a central question in insect flight research. However, physical and computational models have yielded conflicting results regarding whether wing deformations enhance or diminish flight forces. By experimentally stiffening the wings of live bumblebees, we demonstrate that wing flexibility affects aerodynamic force production in a natural behavioural context. Bumblebee wings were artificially stiffenedin vivoby applying a micro-splint to a single flexible vein joint, and the bees were subjected to load-lifting tests. Bees with stiffened wings showed an 8.6 per cent reduction in maximum vertical aerodynamic force production, which cannot be accounted for by changes in gross wing kinematics, as stroke amplitude and flapping frequency were unchanged. Our results reveal that flexible wing design and the resulting passive deformations enhance vertical force production and load-lifting capacity in bumblebees, locomotory traits with important ecological implications.
Assembly chaperones: a perspective
Authors: Ellis R. John
Published: March 2013

The historical origins and current interpretation of the molecular chaperone concept are presented, with the emphasis on the distinction between folding chaperones and assembly chaperones. Definitions of some basic terms in this field are offered and misconceptions pointed out. Two examples of assembly chaperone are discussed in more detail: the role of numerous histone chaperones in fundamental nuclear processes and the co-operation of assembly chaperones with folding chaperones in the production of the world's most important enzyme.
Regulation of Arabidopsis Leaf Hydraulics Involves Light-Dependent Phosphorylation of Aquaporins in Veins
Authors: Prado Karine , Boursiac Yann , Tournaire-Roux Colette , Monneuse Jean-Marc , Postaire Olivier , Da Ines Olivier , Schäffner Anton R. , Hem Sonia , Santoni Véronique , Maurel Christophe
Published: March 2013

The water status of plant leaves depends on the efficiency of the water supply, from the vasculature to inner tissues. This process is under hormonal and environmental regulation and involves aquaporin water channels. In Arabidopsis thaliana, the rosette hydraulic conductivity (K  ros) is higher in darkness than it is during the day. Knockout plants showed that three plasma membrane intrinsic proteins (PIPs) sharing expression in veins (PIP1;2, PIP2;1, and PIP2;6) contribute to rosette water transport, and PIP2;1 can fully account for K  ros responsiveness to darkness. Directed expression of PIP2;1 in veins of a pip2;1 mutant was sufficient to restore K  ros. In addition, a positive correlation, in both wild-type and PIP2;1-overexpressing plants, was found between K  ros and the osmotic water permeability of protoplasts from the veins but not from the mesophyll. Thus, living cells in veins form a major hydraulic resistance in leaves. Quantitative proteomic analyses showed that light-dependent regulation of K  ros is linked to diphosphorylation of PIP2;1 at Ser-280 and Ser-283. Expression in pip2;1 of phosphomimetic and phosphorylation-deficient forms of PIP2;1 demonstrated that phosphorylation at these two sites is necessary for K  ros enhancement under darkness. These findings establish how regulation of a single aquaporin isoform in leaf veins critically determines leaf hydraulics.
Modularity of Plant Metabolic Gene Clusters: A Trio of Linked Genes That Are Collectively Required for Acylation of Triterpenes in Oat
Authors: Mugford Sam T. , Louveau Thomas , Melton Rachel , Qi Xiaoquan , Bakht Saleha , Hill Lionel , Tsurushima Tetsu , Honkanen Suvi , Rosser Susan J. , Lomonossoff George P. , Osbourn Anne
Published: March 2013

Operon-like gene clusters are an emerging phenomenon in the field of plant natural products. The genes encoding some of the best-characterized plant secondary metabolite biosynthetic pathways are scattered across plant genomes. However, an increasing number of gene clusters encoding the synthesis of diverse natural products have recently been reported in plant genomes. These clusters have arisen through the neo-functionalization and relocation of existing genes within the genome, and not by horizontal gene transfer from microbes. The reasons for clustering are not yet clear, although this form of gene organization is likely to facilitate co-inheritance and co-regulation. Oats (Avena spp) synthesize antimicrobial triterpenoids (avenacins) that provide protection against disease. The synthesis of these compounds is encoded by a gene cluster. Here we show that a module of three adjacent genes within the wider biosynthetic gene cluster is required for avenacin acylation. Through the characterization of these genes and their encoded proteins we present a model of the subcellular organization of triterpenoid biosynthesis.
European consumer perceptions and barriers for fresh, frozen, preserved and ready‐meal fish products
Authors: Vanhonacker Filiep , Pieniak Zuzanna , Verbeke Wim
Published: March 2013

Purpose

This study aims to investigate consumers' perceptions and barriers in relation to fresh, frozen, preserved and ready‐meal fish products in a geographically diverse selection of European countries.

Design/methodology/approach

Cross‐sectional data were collected through a consumer survey (n=3,213), conducted in June 2008 in the Czech Republic, Germany, Greece, Italy, Portugal, Romania, Sweden and the UK. Items measured were self‐reported consumption frequencies, consumer perceptions of different fish product categories, and perceived barriers for increased fish consumption levels. Country specificities are discussed.

Findings

The overriding healthy perception consumers have about fish was confirmed, and contributed very strongly to the general perception consumers have about fish. Fresh fish was perceived the most healthy fish product, followed by frozen, preserved and ready‐meal fish products. Perception scores were highest correlated with self‐reported fish consumption in the Mediterranean countries. With the exception of Romania, perceived barriers only poorly explained self‐reported consumption frequencies of the different fish product categories. This finding is related to the possible influence of habit and tradition with regard to eating fish, to the absence of measures related to motivations or drivers to consume fish, or to the possibility that some of the perceived barriers reinforce each other. In the Mediterranean countries, fish consumption frequency is on a very high level, independently of perceived barriers and motivational aspects, and part of the traditional Mediterranean diet.

Originality/value

The strength of this study pertains to its international scope and geographical spread. Further, consumer perceptions and perceived barriers in relation to fresh, frozen, preserved and ready‐meal fish products have rarely been studied in parallel. Findings are relevant to support efforts on national and international level to stimulate or modify fish consumption, and to explore opportunities to trade fish products.
Consumers' health and taste attitude in Taiwan
Authors: Chen Mei‐Fang
Published: March 2013

Purpose

Previous studies indicate that both health and taste are important factors in the food choice process. Owing to the industrialization of food processing and biotechnological innovations on the one hand and a series of food scandals on the other, consumers are now more concerned about modern food hazards. The present study aims to investigate whether consumers with varying degrees of modern tainted foods worries and gender difference will show variations in the Health and Taste Attitude Scales (HTAS).

Design/methodology/approach

Of a total of 1,500 questionnaires sent out, 533 were found useful for this empirical analysis. The measurement items of the Health and Taste Attitude Scale (HTAS) were scored as the data input to test for the impacts of modern tainted foods worries and gender by ANOVA tests.

Findings

The results of this study conducted in Taiwan indicate that those people identified in the ‘‘high modern tainted foods worries’’ group have more interests in health in foods but the ‘‘low modern tainted foods worries’’ group have more interests in taste in foods. In addition, though more concerned about health in foods, female consumers are also more interested in sweet foods.

Practical implications

Some suggestions for food marketers and food policy makers are also provided in this study.

Originality/value

To the best knowledge of this researcher, this study represents one of the first attempts to investigate the health and taste attitudes in Taiwan and tests for the impacts of modern tainted foods worries and gender.
Daily nutrient contribution of meals served in the home grown school feeding of Osun State, Nigeria
Authors: Agbon C.A. , Onabanjo O.O. , Okeke E.C.
Published: March 2013

Purpose

The Home Grown School Feeding and Health Programme (HGSHP) in Nigeria provides primary school pupils across the country with one meal daily. The purpose of this paper is to standardize the HGSHP meals in Osun State and determine the energy, protein and mineral contribution to the school children's daily nutrient intake.

Design/methodology/approach

All the HGSHP meals served school children were studied. Questionnaire, standardization of recipe and chemical analysis were employed to evaluate the HGSHP meals and to suggest improvement.

Findings

All the meals were cooked. Dishes composed of a mixture of a legume (cowpea) commonly called beans, a cereal (maize or rice) or tuber (yam) taken with a soup or stew and fish or egg. The bean meals were high in protein and carbohydrate. All the dishes had very low zinc content and did not meet 30 per cent of the school children's daily zinc requirements.

Originality/value

This paper may be the first to evaluate the nutritional contribution of school meals in Nigeria.
Principal phenolic phytochemicals and antioxidant property in Eucalyptus bark
Authors: Srivastava Jyoti , Vankar Padma S.
Published: March 2013

Purpose

The purpose of this paper is to carry out phytochemical investigations of different extracts of Eucalyptus globulus bark such as aqueous, methanolic and supercritical carbon dioxide fluid extract (SCFE) with ethyl acetate as entrainer. Three fractions (Eu 8, 9 and 10) containing steroidal δ‐lactone were isolated from SCF extract and the structure of Eu‐10 was earlier determined on the basis of NMR, HPLC‐MS, X‐Ray crystallography.

Design/methodology/approach

Column chromatography led to the isolation of flavonoids, tannins, steroids, etc. in different solvent systems. Isolated steroidal lactone (Eu‐8,9&10) of Withanolide series were tested for the presence of total phenolic content, total flavonoid content and the results were expressed as gGAE/100 g (TPC), and gQE/100 g (TFC), respectively. The antioxidant capacity was evaluated based on their ability to scavenge free radicals generated from ABTS, DPPH, FRAP and H2O2 by spectrophotometric method.

Findings

The result of the present study showed that different extracts of E. globulus bark and the isolated fractions, exhibited different antioxidant activity. This was due to the fact that they contained different amounts of flavonoid and phenolic compounds as per their ability to solubilize these compounds; the high scavenging property of E. globulus may be attributed to hydroxyl groups existing in the phenolic compounds. All the samples exhibited different extent of antioxidant activity (AOA) and showed higher potency when compared with BHT in scavenging action of DPPH free radical. Comparative data analysis showed SCF extract to be better than methanolic and aqueous extracts, both in terms of yield and AOA, while Eu‐10 was the best amongst purified fractions.

Practical implications

The present research has serious implications on identification of natural antioxidants from E. globulus. Natural antioxidants with better structure‐activity relationship are under investigation. Isolation of withanolide from Eucalyptus bark has opened newer horizon for its use.

Social implications

Collection of Eucalyptus bark from the forest (a forest waste) by women folk can be a source of revenue generation and thus has social implication as well. It is an important agro product.

Originality/value

The steroidal lactone (Eu‐10) showed highest radical scavenging effect even at IC50, thus the isolated lactone proved to be the best potential scavenger of free radicals amongst all crude extracts and the isolated fractions.
Aflatoxins level in tea samples in Amol (north of Iran)
Authors: Mohamadi Sani Ali , Gholampoor Azizi Eisa , Naeejic Zinat
Published: March 2013

Purpose

The purpose of this paper is to detect total aflatoxin (AFT) in domestic and imported tea in Amol (north of Iran).

Design/methodology/approach

A total of 42 tea samples including 21 domestic and 21 imported tea samples of three popular commercial brands were purchased from retail stores and analyzed for estimation of AFT by ELISA technique. Data were analyzed by ANOVA using SPSS software.

Findings

All of the tea samples were contaminated with detectable amount of AFT ranging from 1.5‐16.5 ng/g. The average±SD concentration of AFT in domestic and imported samples was 7.1±2.96 and 6.11±3.94 ng/g, respectively, which is lower than national and EU standards (10 ng/g). The AFT content in 9.5 and 14.3 percent of domestic and imported samples was more than the limited concentration, respectively. There was no significant difference in AFT content of samples of different commercial brands (p>0.05).

Originality/value

No research had been done to detect and compare the AFT content of domestic and imported tea in Iran.
Study of the mineral nutrients composition of three genotypes of peanuts
Authors: Claudia Rodrigues Angela , Luzia Ströher Gisely , Felidade Dias Lucia , Eduardo Silva Carlos , Matsushita Makoto , Vergilio Visentainer Jesuí , Evelázio de Souza Nilson
Published: March 2013

Purpose

The purpose of this paper is to determine the effect of the genotype on the mineral composition (Ca, Cu, Fe, Mg, Mn, Se, Zn and K) of peanuts.

Design/methodology/approach

Samples of peanut of three genotypes common names cultivar cavalo vermelho (CCV), cultivar cavalo rosa (CCR) and cultivar tatu (CTA) were used. They were grown in the Maringá, Paraná State region in the same period and were purchased directly from the producer. About 500 g of each genotype were purchased and divided into five equal parts. Each part was analyzed separately and in triplicate (n=15). Mineral analysis was performed in an atomic absorption spectrophotometer with flame ionization.

Findings

Among the analyzed minerals, K occurred in the greatest amount (−600 mg · 100 g−1 of sample), followed by Mg (−250 mg · 100 g−1 of sample), and calcium (−65 mg · 100 g−1 of sample). These values were statistically equal for the investigated genotypes. The iron content varied significantly between samples (from 2.7 to 4.6 mg · 100 g−1 of sample). Zinc content ranged between 6 and 10 mg · 100 g−1 of sample. The contents of the other minerals (Cu, Mn, and Se) were lower than 4 mg · 100 g−1 of sample for all genotypes. The quantities of Mn and Se ranged between 1.2 and 2.1 mg · 100 g−1.

Originality/value

Have few studies of comparative variation in minerals contents in different genotypes of peanuts. In relation to the RDI, the paper observed that 100 g of peanuts can provide significant amounts of most minerals or even more than the RDI amounts, all genotypes being very nutritious.
Antiproliferative activity of Bacaba (Oenocarpus bacaba) and Jenipapo (Genipa americana L.) phenolic extracts
Authors: Abadio Finco Fernanda D.B. , Böser Sabrina , Graeve Lutz
Published: March 2013

Purpose

The aim of this work is to assess antiproliferative effects of phenolic extracts from Bacaba (Oenocarpus bacaba) and Jenipapo (Genipa americana) fruits through a comparison of assays.

Design/methodology/approach

Bacaba and Jenipapo phenolic extracts in a concentration range from 0 to 1400 μg/mL were tested by four different assays (MTT, MUH, methylene blue, trypan blue) to assess the antiproliferative potential of the phenolic compounds of these fruits.

Findings

MTT test can be applied with confidence to assess antiproliferative activity to the fruits extracts here studied. The extract of Bacaba showed higher antiproliferative activity than the one of Jenipapo.

Originality/value

Getting to know biofunctional properties of locally consumed fruits such as Bacaba and Jenipapo could enhance commercial properties to these fruits. This study is the first to one to assess the antiproliferative activity of the Brazilian fruits Bacaba and Jenipapo.
A phased dietary and lifestyle approach for the treatment of Premenstrual Syndrome
Authors: Bussell Gaynor
Published: March 2013

Purpose

Although affecting most women during their fertile years, PMS remains a poorly understood condition. The purpose of this paper is to present some diet and lifestyle treatment options based on literature review findings tempered with the author's experience of treating this condition.

Design/methodology/approach

Findings from the literature over the last 20 years and the experience of treating women with this condition have resulted in the development of a phased approach to treat PMS.

Findings

The phased approach is outlined as such: for phase 1 ensure the diet is healthy and balanced. In phase 2 swap high Glycemic Index foods for lower GI ones and eat regular meals. For phase 3 try supplements with evidence of efficacy such as calcium and vitamin D. Finally, in phase 4 address lifestyle factors such as activity, stress and weight plus control chronic health conditions.

Research limitations/implications

More research is needed in this area; future work should focus on the use of the lower GI diet and weight loss.

Practical implications

The four phased approach should be implemented before resorting to pharmacological intervention. Women may not need to follow all four phases and may find relief after just phase 1.

Social implications

For PMS relief, women do not need to be following a diet that does not fit into a family situation; following the guidelines can have knock on health benefit on the rest of the family.

Originality/value

Unsubstantiated anecdotes are often the main source of help for PMS sufferers. This approach sets achievable phased targets based on sound science and practical experience.
Antibacterial activity of oregano essential oil against foodborne pathogens
Authors: Gonçalves Cattelan Marília , Bonatto Machado de Castilhos Maurício , Juliana Pinsetta Sales Priscila , Leite Hoffmann Fernando
Published: March 2013

Purpose

This paper aims to evaluate in vitro antibacterial activity of oregano essential oil against foodborne pathogens as a starting point for the use of spice as a natural preservative in food.

Design/methodology/approach

Disc and well‐diffusion assays were performed to investigate antibacterial activity of oregano essential oil against six bacteria strains: Bacillus cereus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella Typhimurium. Three concentrations of oregano essential oil were employed: 1.0 percent, 2.0 percent and 5.0 percent. Bacterial growth inhibition was determinate as the diameter of the inhibition zones.

Findings

Oregano essential oil showed antibacterial activity against spoilage microorganisms, at different concentrations, except for P. aeruginosa. There was a significant difference between methodologies only for the microorganism S. aureus. The results provided evidence of the existence of significant differences among the concentrations of oregano essential oil for each microorganism evaluated.

Research limitations/implications

Although the research for this paper involved only oregano essential oil, it provided a starting‐point for further investigations concerning spices as natural preservatives for food systems.

Practical implications

Disc and well‐assays were found to be simple and reproducible practical methods. Other spices, their essential oil and extracts might be researched against other micro‐organisms. Furthermore, in situ studies need to be performed to evaluate possible interactions between essential oils and compounds naturally present in food against microbial strains.

Social implications

The imminent adoption of measures to reduce the use of additives in foods and the reduction on using such compounds.

Originality/value

This study provides insights that suggest a promising exploratory development of food natural preservative against spoilage microorganisms in food systems by the use of oregano essential oil.
International volunteering: employability, leadership and more
Authors: Rothwell Andrew , Charleston Brandon
Published: March 2013

Purpose

The purpose of this paper is to investigate the experiences of individuals in transition between education and work during international volunteering expeditions. While it was expected that outcomes might include employability enhancement and skill development, the authors aimed to clarify what the main factors were, examine employability related factors in relation to other groups of variables, investigate development needs perceived by individuals, and evaluate the extent to which factors explored were influenced by participant attributes. Finally, the authors aim to integrate these findings into a series of recommendations for future research.

Design/methodology/approach

The study involved 406 respondents in three countries, where data were collected in the field. Survey design was based on previous related studies in volunteering and employability. Principal components analyses revealed a four‐component structure relating to leadership and teamwork, the environment and empathy, values and volunteering, and personal skills.

Findings

Employability enhancement was not a primary motive for engaging in the expeditions. Data suggest that respondents had much more altruistic motivations, with perceived benefits more associated with emotional capital development and authentic leadership, although respondents also acknowledged an enhanced ability to deal with selection processes due to their enriched experiences.

Research limitations/implications

In undertaking this work using quantitative methods, the authors acknowledge that they have limited access to the richness of data that might emerge from more in depth narrative analysis. Further research could engage respondents in focus group studies.

Practical implications

The implications of this research are for individuals, that engagement with international volunteering for disingenuous reasons such as CV enhancement is likely to lead to failure, and for employers that individuals who have engaged are likely to have benefited from significant development in leadership skills. For international volunteering organisations, promotion of the employability‐enhancing attributes of the expedition may be less relevant to potential participants than the richness of the experience itself.

Social implications

Engagement with international volunteering is personally transformative as well as delivering benefits in the context of the communities where the volunteering took place. While some respondents were drawn from a “widening participation” background there were no significant differences in their responses.

Originality/value

The authors believe this is the first study to attempt a detailed analysis of the range of attributes potentially held by individuals engaging in international volunteering expeditions.
Investigating a flexible wind turbine using consistent time‐stepping schemes
Authors: Anders Denis , Uhlar Stefan , Krüger Melanie , Groß Michael , Weinberg Kerstin
Published: March 2013

Purpose

Wind turbines are of growing importance for the production of renewable energy. The kinetic energy of the blowing air induces a rotary motion and is thus converted into electricity. From the mechanical point of view the complex dynamics of wind turbines become a matter of interest for structural optimization and optimal control in order to improve stability and energy efficiency. The purpose of this paper therefore is to present a mechanical model of a three‐blade wind turbine with a momentum and energy conserving time integration of the system.

Design/methodology/approach

The authors present a mechanical model based upon a rotationless formulation of rigid body dynamics coupled with flexible components. The resulting set of differential‐algebraic equations will be solved by using energy‐consistent time‐stepping schemes. Rigid and orthotropic‐elastic body models of a wind turbine show the robustness and accuracy of these schemes for the relevant problem.

Findings

Numerical studies prove that physically consistent time‐stepping schemes provide reliable results, especially for hybrid wind turbine models.

Originality/value

The application of energy‐consistent methods for time discretization is intended to provide computational robustness and to reduce the computational costs of the dynamical wind turbine systems. The model is aimed to give a first access into the investigation of fluid‐structure interaction for wind turbines.
A numerical study on effect of temperature and inertia on tolerance design of mechanical assembly
Authors: Jayaprakash G. , Sivakumar K. , Thilak M.
Published: March 2013

Purpose

Due to technological and financial limitations, nominal dimension may not be able achievable during manufacturing process. Therefore, tolerance allocation is of significant importance for assembly. Conventional tolerance analysis methods are limited by the assumption of the part rigidity. Every mechanical assembly consists of at least one or more flexible parts which undergo significant deformation due to gravity, temperature change, etc. The deformation has to be considered during tolerance design of the mechanical assembly, in order to ensure that the product can function as intended under a wide range of operating conditions for the duration of its life. The purpose of this paper is to determine the deformation of components under inertia effect and temperature effect.

Design/methodology/approach

In this paper, finite element analysis of the assembly is carried out to determine the deformation of the components under inertia effect and temperature effect. Then the deformations are suitably incorporated in the assembly functions generated from vector loop models. Finally, the tolerance design problem is optimized with an evolutionary technique.

Findings

With the presented approach, the component tolerance values found are the most robust to with stand temperature variation during the product's application. Due to this, the tolerance requirements of the given assembly are relaxed to certain extent for critical components, resulting in reduced manufacturing cost and high product reliability. These benefits make it possible to create a high‐quality and cost‐effective tolerance design, commencing at the earliest stages of product development.

Originality/value

With the approach presented in the paper, the component tolerance values found were the most robust to withstand temperature variation during the product's application. Due to this, the tolerance requirements of the given assembly are relaxed to a certain extent for critical components, resulting in reduced manufacturing cost and high product reliability. These benefits make it possible to create a high‐quality and cost‐effective tolerance design, commencing at the earliest stages of product development.