bluuebunny/crossref_metadata_2025 huggingface dataset:
Surfactant effects of gallium on quality of AlN epilayers grown via metal-organic chemical-vapour deposition on SiC substrates
Authors: Al tahtamouni T M , Li J , Lin J Y , Jiang H X
Published: June 2012

Effects of gallium as a surfactant for the growth of AlN epilayers on SiC substrates by metal-organic chemical-vapour deposition have been studied. It was found that the use of gallium as a surfactant enables the growth of thick, crack-free AlN epilayers on SiC substrates. The photoluminescence and x-ray diffraction (XRD) analysis show that gallium surfactant can reduce some of the tensile strain in AlN epilayers and it improves the surface smoothness. XRD rocking curves yielded decreased full widths at half maximum for the (1 0 5) and (0 0 2) reflections, indicating a reduction in threading dislocation density in the AlN epilayers.
Study of dc micro-discharge arrays made in silicon using CMOS compatible technology
Authors: Kulsreshath M K , Schwaederle L , Overzet L J , Lefaucheux P , Ladroue J , Tillocher T , Aubry O , Woytasik M , Schelcher G , Dussart R
Published: June 2012

In this paper we present the fabrication technology used to make micro-discharge ‘reactors’ on a silicon (Si) substrate. For the fabrication of these reactors we have used Si wafers with 4 inch diameter and standard cleanroom facilities. The fabrication technology used is compatible with standard CMOS device fabrication and the fabricated micro-discharge reactors can be used to produce dc discharges. These micro-discharges operate at near atmospheric pressure. They were given ring-shaped anodes separated from the cathode by a SiO2 dielectric with a thickness of approximately 5–6 µm rather than the much more common ∼100 µm. The micro-discharge reactors can consist of either a single hole or multiple holes and we have built devices with holes from 25 to 150 µm in diameter. The micro-discharge measurements were obtained for helium and argon dc plasmas between 100 and 1000 Torr. We used a single ballast resistor to produce micro-discharges in multi-hole array. This resistor also acted to limit the discharge power. An average current density of 0.8 A cm−2 was calculated for the 1024 holes array with 100 µm diameter holes. In addition, we will report on stability of micro-discharges depending on the cavity configuration of the micro-reactors and the ignition trends for the micro-discharge arrays. Finally, we discuss the life time of micro-discharge arrays as well as the factors affecting them (cathode sputtering, thermally affected zones, etc).
Simultaneous linearization for commuting quasiperiodically forced circle diffeomorphisms
Authors: Wang Jing , Zhou Qi
Published: June 2012

For commuting smooth quasiperiodically forced circle diffeomorphisms, we show that if the base frequencies and the fibred rotation numbers jointly satisfy some simultaneous Diophantine condition and if the diffeomorphisms are in some

C

∞

C^{\infty }

neighborhood of the corresponding rotations, then they are simultaneously

C

∞

C^{\infty }

-linearizable.
Polarization of actin cytoskeleton is reduced in dendritic protrusions during early spine development in hippocampal neuron
Authors: Tatavarty Vedakumar , Das Sulagna , Yu Ji
Published: June 2012

Dendritic spines are small protrusions that receive synaptic signals in neuronal networks. The actin cytoskeleton plays a key role in regulating spine morphogenesis, as well as in the function of synapses. Here we report the first quantitative measurement of F-actin retrograde flow rate in dendritic filopodia, the precursor of dendritic spines, and in newly formed spines, using a technique based on photoactivation localization microscopy. We found a fast F-actin retrograde flow in the dendritic filopodia but not in the spine necks. The quantification of F-actin flow rates, combined with fluorescence recovery after photobleaching measurements, allowed for a full quantification of spatially resolved kinetic rates of actin turnover, which was not previously feasible. Furthermore we provide evidences that myosin II regulates the actin flow in dendritic filopodia and translocates from the base to the tip of the protrusion upon spine formation. Rac1 inhibition led to mislocalization of myosin II, as well as to disruption of the F-actin flow. These results provide advances in the quantitative understanding of F-actin remodeling during spine formation.
Pac-man motility of kinetochores unleashed by laser microsurgery
Authors: LaFountain James R. , Cohan Christopher S. , Oldenbourg Rudolf
Published: June 2012

We report on experiments directly in living cells that reveal the regulation of kinetochore function by tension. X and Y sex chromosomes in crane fly (Nephrotoma suturalis) spermatocytes exhibit an atypical segregation mechanism in which each univalent maintains K-fibers to both poles. During anaphase, each maintains a leading fiber (which shortens) to one pole and a trailing fiber (which elongates) to the other. We used this intriguing behavior to study the motile states that X-Y kinetochores are able to support during anaphase. We used a laser microbeam to either sever a univalent along the plane of sister chromatid cohesion or knock out one of a univalent's two kinetochores to release one or both from the resistive influence of its sister's K-fiber. Released kinetochores with attached chromosome arms moved poleward at rates at least two times faster than normal. Furthermore, fluorescent speckle microscopy revealed that detached kinetochores converted their functional state from reverse pac-man to pac-man motility as a consequence of their release from mechanical tension. We conclude that kinetochores can exhibit pac-man motility, even though their normal behavior is dominated by traction fiber mechanics. Unleashing of kinetochore motility through loss of resistive force is further evidence for the emerging model that kinetochores are subject to tension-sensitive regulation.
Do Security‐Differentiated Water Rights Improve the Performance of Water Markets?
Authors: Lefebvre Marianne , Gangadharan Lata , Thoyer Sophie
Published: June 2012

Most existing water markets combine water rights trading and water allocation trading. Offering security‐differentiated water rights can make the market more efficient and allow water users to manage the risks of supply uncertainty better. We conduct a laboratory experiment which compares two designs for water rights; one with a single security level and another with two security levels. We find that a two security level system increases overall profits when transactions costs are lower on the water rights market than on the water allocation market. It also improves risk allocation by allowing subjects to trade‐off profits variability against expected profits according to their risk type and this result is robust to the existence of transactions costs on either market.
The effect of metformin on insulin resistance and exercise parameters in patients with heart failure
Authors: Wong Aaron K.F. , Symon Ruth , AlZadjali Matlooba A. , Ang Donald S.C. , Ogston Simon , Choy AnnaMaria , Petrie John R. , Struthers Allan D. , Lang Chim C.
Published: June 2012

Aims

Chronic heart failure (CHF) is an insulin‐resistant state. The degree of insulin resistance (IR) correlates with disease severity and is associated with reduced exercise capacity. In this proof of concept study, we have examined the effect of metformin on IR and exercise capacity in non‐diabetic CHF patients identified to have IR.

Methods and results

In a double‐blind, placebo‐controlled study, 62 non‐diabetic IR CHF patients (mean age, 65.2 ± 8.0 years; male, 90%; left ventricular ejection fraction, 32.6 ± 8.3%; New York Heart Association class I/II/III/IV, 11/45/6/0) were randomized to receive either 4 months of metformin (n = 39, 2 g/day) or matching placebo (n = 23). IR was defined by a fasting insulin resistance index (FIRI) ≥2.7. Cardiopulmonary exercise testing and FIRI were assessed at baseline and after 4 months of intervention. Compared with placebo, metformin decreased FIRI (from 5.8 ± 3.8 to 4.0 ± 2.5, P < 0.001) and resulted in a weight loss of 1.9 kg (P < 0.001). The primary endpoint of the study, peak oxygen uptake (VO2), did not differ between treatment groups. However, metformin improved the secondary endpoint of the slope of the ratio of minute ventilation to carbon dioxide production (VE/VCO2 slope), from 32.9 ± 15.9 to 28.1 ± 8.8 (P = 0.034). In the metformin‐treated group, FIRI was significantly related to the reduction of the VE/VCO2 slope (R = 0.41, P = 0.036).

Conclusion

Metformin treatment significantly improved IR but had no effect on peak VO2, the primary endpoint of our study. However, metformin treatment did result in a significant improvement in VE/VCO2 slope. Trial registration: NCT00473876.
Regulation of ASIC channels by a stomatin/STOML3 complex located in a mobile vesicle pool in sensory neurons
Authors: Lapatsina Liudmila , Jira Julia A. , Smith Ewan St. J. , Poole Kate , Kozlenkov Alexey , Bilbao Daniel , Lewin Gary R. , Heppenstall Paul A.
Published: June 2012

A complex of stomatin-family proteins and acid-sensing (proton-gated) ion channel (ASIC) family members participate in sensory transduction in invertebrates and vertebrates. Here, we have examined the role of the stomatin-family protein stomatin-like protein-3 (STOML3) in this process. We demonstrate that STOML3 interacts with stomatin and ASIC subunits and that this occurs in a highly mobile vesicle pool in dorsal root ganglia (DRG) neurons and Chinese hamster ovary cells. We identify a hydrophobic region in the N-terminus of STOML3 that is required for vesicular localization of STOML3 and regulates physical and functional interaction with ASICs. We further characterize STOML3-containing vesicles in DRG neurons and show that they are Rab11-positive, but not part of the early-endosomal, lysosomal or Rab14-dependent biosynthetic compartment. Moreover, uncoupling of vesicles from microtubules leads to incorporation of STOML3 into the plasma membrane and increased acid-gated currents. Thus, STOML3 defines a vesicle pool in which it associates with molecules that have critical roles in sensory transduction. We suggest that the molecular features of this vesicular pool may be characteristic of a ‘transducosome’ in sensory neurons.
Prognostic impact of Raf‐1 and p‐Raf‐1 expressions for poor survival rate in non‐small cell lung cancer
Authors: Qiu Zhi‐Xin , Wang Lei , Han Juan , Liu Dan , Huang Wei , Altaf Kiran , Qiu Xue‐Song , Javed Muhammad A. , Zheng Jing , Chen Bo‐Jiang , Li Wei‐Min
Published: June 2012

Overexpression of Raf‐1 has commonly been observed in solid tumors including non‐small cell lung cancer (NSCLC). The objective of this study was to investigate whether overexpression of Raf‐1, phosphorylated‐Raf‐1 (p‐Raf‐1) or both correlates with poor survival rate in NSCLC patients and to explore associations between expression of these proteins and NSCLC cell fate both in vitro and in vivo. Expression of Raf‐1 and p‐Raf‐1 were detected by immunohistochemistry in tumor specimens from 152 NSCLC patients and associations between their expression and the clinicopathological characteristics were assessed. Five‐year median survival rate of patients were analyzed by Kaplan–Meier method, log‐rank test and Cox regression. Cell fate was compared between normal tumor cells and those with Raf‐1 silencing, in both the adenocarcinoma cell line A549 and xenografted mice that were infected with the A549 cell line. The incidence of overexpression of both Raf‐1 and p‐Raf‐1 in NSCLC was much higher than normal control (P < 0.05), and the survival rate of patients with positive expression of Raf‐1, p‐Raf‐1 or both was found to be significantly lower than the negative group (P < 0.05). Both univariate and multivariate analyses showed Raf‐1 (P = 0.000, P = 0.010), p‐Raf‐1 (P = 0.004, P = 0.046), or both (P = 0.001, P = 0.016) was good prognostic markers for poor survival rate in NSCLC patients. Suppression of Raf‐1 inhibited tumorigenesis by inducing apoptosis both in vitro and in vivo. These findings demonstrate that overexpression of Raf‐1, p‐Raf‐1 or both could be considered as a new independent prognostic biomarker for poor survival rates for NSCLC patients.
HrpM is involved in glucan biosynthesis, biofilm formation and pathogenicity in Xanthomonas citri ssp. citri
Authors: Malamud Florencia , Conforte Valeria P. , Rigano Luciano A. , Castagnaro Atilio P. , Marano María Rosa , Morais do Amaral Alexandre , Vojnov Adrian A.
Published: June 2012

Xanthomonas citri ssp. citri (Xcc) is the causal agent of citrus canker. This bacterium develops a characteristic biofilm on both biotic and abiotic surfaces. A biofilm‐deficient mutant was identified in a screening of a transposon mutagenesis library of the Xcc 306 strain constructed using the commercial Tn5 transposon EZ‐Tn5  Tnp Transposome (Epicentre). Sequence analysis of a mutant obtained in the screening revealed that a single copy of the EZ‐Tn5 was inserted at position 446 of hrpM, a gene encoding a putative enzyme involved in glucan synthesis. We demonstrate for the first time that the product encoded by the hrpM gene is involved in β‐1,2‐glucan synthesis in Xcc. A mutation in hrpM resulted in no disease symptoms after 4 weeks of inoculation in lemon and grapefruit plants. The mutant also showed reduced ability to swim in soft agar and decreased resistance to H
2
O
2 in comparison with the wild‐type strain. All defective phenotypes were restored to wild‐type levels by complementation with the plasmid pBBR1‐MCS containing an intact copy of the hrpM gene and its promoter. These results indicate that the hrpM gene contributes to Xcc growth and adaptation in its host plant.
Some ways to improve QTL mapping accuracy
Authors: Korol Abraham , Frenkel Zeev , Orion Ori , Ronin Yefim
Published: June 2012

In this paper, we review some approaches for QTL mapping developed by our research group in collaboration with, following the recommendation of, or under inspiration of Moshe Soller. Specifically, we explain at a simple intuitive level the main principles and ideas of: (a) QTL mapping by fractioned DNA pooling, (b) increasing the detection power of QTL mapping (in the case of individual genotyping) by multiple‐trait analysis, and (c) the role of variance–covariance effects in QTL mapping. On each of these themes we had long and deep discussions with Soller on the statistical aspects of the proposed procedures. We hope that together we made important contributions towards making QTL mapping procedures easier and more effective.
Genetic parameters for paratuberculosis infection and effect of infection on production traits inIsraeliHolsteins
Authors: Shook G. E. , Chaffer M. , Wu X.‐L. , Ezra E.
Published: June 2012

Paratuberculosis (Johne's disease) is an infectious enteric disease in dairy cattle and other species that causes substantial economic loss worldwide. In this study, two recursiveGaussian‐threshold models were employed in order to infer the effects ofJohne's disease on milk yield, fat yield, and protein yield while simultaneously estimating genetic parameters (i.e. heritability and genetic correlation) in anIsraeliHolstein population. Disease diagnosis was based onELISAserum antibody tests. Data were available for 4694 daughters of 361 sires; 3.5% were positive; and 1.6% were suspect for the disease test. Disease status was coded either as a binary character (negative vs. positive) or as an ordered categorical trait (negative, suspect, and positive) in the two recursive models and as a binary trait in a linear model. Among sires with ≥50 daughters, predicted probability ofMycobacterium aviumssp.paratuberculosis(MAP) infection in future daughters ranged from <1% to 16.5%. Heritability estimates forJohne's disease were near 0.15, confirming a genetic contribution to disease susceptibility. Genetic correlation estimates forJohne's disease with the three yield traits were 0.15–0.22. Residual correlations forJohne's disease with the yield traits were between −0.01 and −0.10. For the linear regression model, yield losses associated with a positive disease diagnosis during 305 days of lactation were 300 kg milk and around 10 kg for fat and protein. Yield loss estimates from the recursive models were 25–50% less than linear model estimates. Recursive modeling has theoretical advantages over linear models for these phenotypes, but the estimated genetic parameters in this study did not differ significantly between the two types of models.
QTL mapping of complex binary traits in an advanced intercross line
Authors: Moradi Marjaneh M. , Martin I. C. A. , Kirk E. P. , Harvey R. P. , Moran C. , Thomson P. C.
Published: June 2012

An advanced intercross line (AIL) is an easier and more cost‐effective approach compared to recombinant inbred lines for fine mapping of quantitative trait loci (QTL) identified by F2designs. In an AIL, a complex binary trait can be mapped through analysis of either continuously distributed proxy traits for the liability of the binary trait or the liability itself, the latter presenting the greater statistical challenge. In another work, we successfully applied both approaches in an AIL to fine map previously identified QTL underlying anatomical parameters of the cardiac inter‐atrial septum including patent foramen ovale. Here, we describe the statistical methods that we used to analyse complex binary traits in our AIL design. This is achieved using a likelihood‐based method, with the expectation–maximisation algorithm allowing use of standard logistic regression methods for model fitting.
Variation in the ovocalyxin‐32 gene in commercial egg‐laying chickens and its relationship with egg production and egg quality traits
Authors: Fulton J. E. , Soller M. , Lund A. R. , Arango J. , Lipkin E.
Published: June 2012

Avian eggshell quality is an important trait for commercial egg production, as the eggshell is the primary packaging material and antimicrobial barrier for the internal food resource. Strong eggshells are essential to ensure that eggs can reach their final destination without damage. Ovocalyxin‐32 (OCX32) is a matrix protein found within the outer layers of the eggshell and in the cuticle. Numerous reports in the literature have identified association between variants in the gene encoding this protein, OCX32, and various eggshell quality traits. Thus, OCX32 is a candidate gene for selection for eggshell traits in commercial poultry populations. Sequencing of exons 2–6 of the OCX32 gene in eight elite brown and white eggshell commercial egg‐laying lines revealed 28 SNPs and one SNP/indel. Eighteen of these SNPs were predicted to alter the amino acid sequence of the protein. Clusters of SNPs in complete linkage disequilibrium were found in both exons 2 and 6. A total of 19 different versions or protein‐sequence haplotypes of the OCX32 protein were inferred, revealing considerable variation within commercial lines. Genotypes for 13 of the SNPs were determined for 330–1819 individuals per line. Trait association studies revealed a significant effect of OCX32 on shell color in white egg lines and line‐specific significant effects on albumen height, early egg weight, puncture score, and yolk weight. Three of the lines showed a significant change in OCX32 frequency over time, indicating selection pressure for certain variants of this gene during the breeding program.
Critical thinking in the chemical ecology of mammalian communication: roadmap for future studies
Authors: Charpentier Marie J. E. , Barthes Nicolas , Proffit Magali , Bessière Jean‐Marie , Grison Claude
Published: June 2012

1. Sophisticated and sensitive technologies now allow separation, quantification and chemical characterization of numerous compounds that play roles in chemical communication, chemical defence and aggression, in interactions between conspecific or heterospecific individuals. In the particular subfield of mammalian chemical communication, these rapid technological advances, combined with a frequent lack of technical background, have led to important errors in both chemical characterization of molecules and interpretation of their roles as chemical mediators of communication.

2. The aim of this article is to highlight some of these methodological and analytical pitfalls and to provide a basis for better understanding of chemical mediation of communication in mammals. We compiled the recent literature treating molecules found in mammalian secretions and having putative roles in communication. A selection of 41 published studies dealing with 33 mammal species revealed reports of 857 different molecules. Based on the five main metabolic pathways responsible for the biosynthesis of most known secondary metabolites, we propose nine general biochemical rules that will help researchers to avoid errors of chemical characterization and to aid in interpreting the possible functional role of identified molecules as chemical mediators of mammal communication.

3. Following these nine rules, we show that published studies include reports of molecules that are incorrectly or ambiguously named, molecules of exclusively non‐natural origin, molecules produced by other organisms but not directly by mammals, and molecules of biological origin and possibly produced by mammals. Only the last two of these classes could conceivably play roles as mediators of mammalian communication. We discuss the potential roles of these compounds as reported in the publications we reviewed.

4. Our recommendations concerning technical, analytical and statistical aspects of the identification of compounds and interpretation of their roles should help chemical ecologists ask the appropriate questions about the accuracy of their identifications of molecules, the biological relevance of molecules they do identify and the possible functional roles of these molecules in mammalian communication.
Fine root dynamics with stand development in the boreal forest
Authors: Yuan Z. Y. , Chen Han Y. H.
Published: June 2012

1. Despite greater importance of below ground in influencing terrestrial carbon and nutrient cycling than above ground, how below‐ground biomass, production, turnover and mortality change with stand development remains poorly understood.

2. Here, we used a postfire boreal forest chronosequence that spanned over 200 years (3, 11, 29, 94, 142 and 205 years since fire) to study how the dynamics of fine roots (≤2 mm in diameter) vary with stand age. We collected 756 sequential cores and 270 ingrowth cores, each separated to layers and live/dead, resulting in a total of 5076 fine root samples to quantify fine root biomass, production, mortality and turnover rates.

3. With stand development, fine root biomass increased from 3 to 94‐year‐old, and declined thereafter, whereas necromass increased to 142‐year‐old and levelled off at 205‐year‐old. Fine root production and turnover increased from 3 to 11‐year‐old stands, and declined thereafter. Fine root mortality increased from 3 to 142‐year‐old stands.

4. Our study, the first to show four simultaneous stand age–dependent below‐ground attributes, indicated that fine roots in young stands turn over faster than in old stands based on the estimates from both sequential and ingrowth cores. Despite some similarities among the studied attributes, the peaks they reached were not the same. Our results suggest that fine root dynamics are influenced by changes in species composition and soil properties associated with stand development in the boreal forest, especially the increase in forest floor nitrogen: phosphorus ratios as stand age increases.
Participants' experiences of care during a randomized controlled trial comparing a lay‐facilitated angina management programme with usual care: a qualitative study using focus groups
Authors: Nelson Pauline , Cox Helen , Furze Gill , Lewin Robert J.P. , Morton Veronica , Norris Heather , Patel Nicky , Elton Peter , Carty Richard
Published: June 2012

Aim

This paper is a report of a qualitative study conducted as part of a randomized controlled trial comparing a lay‐facilitated angina management programme with usual care. Its aim was to explore participants' beliefs, experiences, and attitudes to the care they had received during the trial, particularly those who had received the angina management intervention.

Background

Angina affects over 50 million people worldwide. Over half of these people have symptoms that restrict their daily life and would benefit from knowing how to manage their condition.

Design

A nested qualitative study within a randomized controlled trial of lay‐facilitated angina management.

Method

We conducted four participant focus groups during 2008; three were with people randomized to the intervention and one with those randomized to control. We recruited a total of 14 participants to the focus groups, 10 intervention, and 4 control.

Findings

Although recruitment to the focus groups was relatively low by comparison to conventional standards, each generated lively discussions and a rich data set. Data analysis demonstrated both similarities and differences between control and intervention groups. Similarities included low levels of prior knowledge about angina, whereas differences included a perception among intervention participants that lifestyle changes were more easily facilitated with the help and support of a lay‐worker.

Conclusion

Lay facilitation with the Angina Plan is perceived by the participants to be beneficial in supporting self‐management. However, clinical expertise is still required to meet the more complex information and care needs of people with stable angina.
Chinese version of Daily Record of Severity of Problems: reliability and validity
Authors: Wu Liping , He Zhong , Zhao Hong , Ma Di , Zhang Sijia , Deng Hanyu , Liang Tao
Published: June 2012

Aim

To report a study of the psychometric properties of the Chinese version of the Daily Record of Severity of Problems form.

Background

In China, the prevalence of premenstrual syndrome is not confirmed due to lack of prospective daily tools. Daily Record of Severity of Problems was a validated daily symptom chart widely used for the diagnosis of premenstrual syndrome. There is no such an instrument for Chinese women.

Methods

The convenience sample included 126 female students in a school of nursing from September 2010–March 2011 in China. All of them completed daily ratings for two menstrual cycles, Premenstrual Tension Syndrome Self‐Rating scale and Zung Self‐Rating Depression scale at the first day of menses in two cycles.

Results

The internal consistency coefficients of reliability for total score and the correlations of each item with the total score in two cycles were all high. The majority of the cycle to cycle test–retest reliability for total scores and the individual items for the two phases of the cycle were high. Factor analysis yielded four factors describing mood, behaviour, pain, and physical symptoms. There were moderate correlations of the total Daily Record of Severity of Problems during the late‐luteal phase of both cycles with Premenstrual Tension Syndrome Self‐Rating scale and Zung Self‐Rating Depression scale.

Conclusions

The Daily Record of Severity of Problems Chinese version provides reliable and valid measures of premenstrual symptoms in Chinese women. It has satisfactory psychometric properties and is suitable for nursing implication.
Origin and in situ diversification in Hemidactylus geckos of the Socotra Archipelago
Authors: GÓMEZ‐DÍAZ ELENA , SINDACO ROBERTO , PUPIN FABIO , FASOLA MAURO , CARRANZA SALVADOR
Published: June 2012

The Socotra Archipelago is an ancient continental fragment of Gondwanan origin and one of the most isolated landforms on Earth and a biodiversity hot spot. Yet, the biogeography and evolutionary history of its endemic fauna still remain largely overlooked. We investigate the origin, tempo and mode of diversification in the Hemidactylus geckos of the Socotra Archipelago. Concatenated and multilocus species coalescent analyses of Hemidactylus from Arabia and North Africa indicate that the Hemidactylus from Socotra do not form a monophyletic group and branch as three independent and well‐supported clades instead. Both the chronogram inferred using the gene tree approach of BEAST and the age‐calibrated multilocus species tree obtained using *BEAST suggest that the origin of Hemidactylus from Socotra may have involved a first vicariance event that occurred in the Early Miocene, followed by two independent transoceanic dispersal events that occurred more recently, during the Pliocene. Within Socotra, we analysed patterns of genetic diversity, the phylogeography and the demographic history in all seven nonintroduced species of Hemidactylus. Results based on two mitochondrial and two nuclear loci from 144 individuals revealed complex patterns of within‐island diversification and high levels of intra‐species genetic divergence. The interplay of both historical and ecological factors seems to have a role in the speciation process of this group of geckos. Interestingly, the case of H. forbesii and H. oxyrhinus, which inhabit the island of Abd al Kuri with an area of 133 km2, may represent one of the most extreme cases of intra‐island speciation in reptiles ever reported.
A complex LuxR–LuxI type quorum sensing network in a roseobacterial marine sponge symbiont activates flagellar motility and inhibits biofilm formation
Authors: Zan Jindong , Cicirelli Elisha M. , Mohamed Naglaa M. , Sibhatu Hiruy , Kroll Stephanie , Choi Okhee , Uhlson Charis L. , Wysoczynski Christina L. , Murphy Robert C. , Churchill Mair E. A. , Hill Russell T. , Fuqua Clay
Published: June 2012

Bacteria isolated from marine sponges, including the Silicibacter–Ruegeria (SR) subgroup of the Roseobacter clade, produce N‐acylhomoserine lactone (AHL) quorum sensing signal molecules. This study is the first detailed analysis of AHL quorum sensing in sponge‐associated bacteria, specifically Ruegeria sp. KLH11, from the sponge Mycale laxissima. Two pairs of luxR and luxI homologues and one solo luxI homologue were identified and designated ssaRI, ssbRI and sscI (sponge‐associated symbiont locus A, B and C, luxR or luxI homologue). SsaI produced predominantly long‐chain 3‐oxo‐AHLs and both SsbI and SscI specified 3‐OH‐AHLs. Addition of exogenous AHLs to KLH11 increased the expression of ssaI but not ssaR, ssbI or ssbR, and genetic analyses revealed a complex interconnected arrangement between SsaRI and SsbRI systems. Interestingly, flagellar motility was abolished in the ssaI and ssaR mutants, with the flagellar biosynthesis genes under strict SsaRI control, and active motility only at high culture density. Conversely, ssaI and ssaR mutants formed more robust biofilms than wild‐type KLH11. AHLs and the ssaI transcript were detected in M. laxissima extracts, suggesting that AHL signalling contributes to the decision between motility and sessility and that it may also facilitate acclimation to different environments that include the sponge host.
Molecular dissection of TatC defines critical regions essential for protein transport and a TatB–TatC contact site
Authors: Kneuper Holger , Maldonado Barbara , Jäger Franziska , Krehenbrink Martin , Buchanan Grant , Keller Rebecca , Müller Matthias , Berks Ben C. , Palmer Tracy
Published: June 2012

The twin arginine transport (Tat) system transports folded proteins across the prokaryotic cytoplasmic membrane and the plant thylakoid membrane. TatC is the largest and most conserved component of the Tat machinery. It forms a multisubunit complex with TatB and binds the signal peptides of Tat substrates. Here we have taken a random mutagenesis approach to identify substitutions in Escherichia coli TatC that inactivate protein transport. We identify 32 individual amino acid substitutions that abolish or severely compromise TatC activity. The majority of the inactivating substitutions fall within the first two periplasmic loops of TatC. These regions are predicted to have conserved secondary structure and results of extensive amino acid insertion and deletion mutagenesis are consistent with these conserved elements being essential for TatC function. Three inactivating substitutions were identified in the fifth transmembrane helix of TatC. The inactive M205R variant could be suppressed by mutations affecting amino acids in the transmembrane helix of TatB. A physical interaction between TatC helix 5 and the TatB transmembrane helix was confirmed by the formation of a site‐specific disulphide bond between TatC M205C and TatB L9C variants. This is the first molecular contact site mapped to single amino acid level between these two proteins.
Nutrition Education and Counselling Provided during Pregnancy: Effects on Maternal, Neonatal and Child Health Outcomes
Authors: Girard Amy Webb , Olude Oluwafunke
Published: June 2012

Nutrition education and counselling (NEC) is a commonly applied strategy to improve maternal nutrition during pregnancy. However, with the exception special populations and specific diets, the effect of NEC on maternal, neonatal and child health outcomes has not been systematically reviewed. Using a modified Child Health Epidemiology Reference Group method we systematically reviewed the literature and identified and abstracted 37 articles. We conducted meta‐analyses for the effect of NEC on maternal, neonatal and infant health outcomes including gestational weight gain, maternal anaemia, birthweight, low birthweight and preterm delivery. NEC significantly improved gestational weight gain by 0.45 kg, reduced the risk of anaemia in late pregnancy by 30%, increased birthweight by 105 g and lowered the risk of preterm delivery by 19%. The effect of NEC on risk of low birthweight was not significant. The effect of NEC was greater when provided with nutrition support, for example, food or micronutrient supplements or nutrition safety nets. The overall quality of the body of evidence was deemed low for all outcomes due to high heterogeneity, poor study designs and other biases. Additional well‐designed research that is grounded in appropriate theories of behaviour change is needed to improve confidence in the effect of NEC. Further, cost‐effectiveness research is needed to clarify the added benefit and sustainability of providing NEC with nutritional support and/or safety nets, especially in areas where food insecurity and gender bias may limit women's capacity to adhere to NEC messages.
The Effects of Household Food Production Strategies on the Health and Nutrition Outcomes of Women and Young Children: A Systematic Review
Authors: Girard Amy Webb , Self Julie L. , McAuliffe Corey , Olude Olafunke
Published: June 2012

The objective of this review is to systematically examine and summarise the effects of agricultural interventions to increase household food production on the nutrition and health outcomes of women and young children and provide recommendations for future research and programming. Data from all studies meeting inclusion/exclusion criteria were abstracted into a standardised form. The quality of the evidence was assessed and graded using a modified version of the Child Health Epidemiology Reference Group adaptation of the Grading of Recommendations, Assessment, Development and Evaluation technique. Thirty‐six articles, representing 27 unique projects were identified. Of these 32 and 17 reported on the health and nutrition outcomes of children and women, respectively. Although studies were too heterogeneous to conduct meta‐analysis, agricultural strategies consistently reported significantly improved diet patterns and vitamin A intakes for both women and children. Although some individual studies reported significant reductions in child malnutrition, summary estimates for effects on stunting [relative risk (RR) 0.93 [95% confidence interval (CI) 0.84, 1.04]], underweight (RR 0.80 [95% CI 0.60, 1.07]) and wasting (RR 0.91 [95% CI 0.60, 1.38]) were not significant. Findings for an effect on vitamin A status, anaemia and morbidity were inconsistent. Overall the evidence base for the potential of agricultural strategies to improve the nutrition and health of women and young children is largely grounded in a limited number of highly heterogeneous, quasi‐experimental studies, most of which have significant methodological limitations. While household food production strategies hold promise for improving the nutrition of women and children, the evidence base would be strengthened by additional research that is methodologically robust and adequately powered for biological and dietary indicators of nutrition.
Vitamin D During Pregnancy and Maternal, Neonatal and Infant Health Outcomes: A Systematic Review and Meta‐analysis
Authors: Thorne‐Lyman Andrew , Fawzi Wafaie W.
Published: June 2012

Vitamin D has well‐defined classical functions related to calcium metabolism and bone health but also has non‐classical effects that may influence other aspects of health. There has been considerable recent interest in the role of vitamin D on outcomes related to pregnancy and young child health but few efforts have been made to systematically consolidate this evidence to inform the research and policy agenda for low‐income countries. A systematic review was undertaken to identify intervention and observational studies of vitamin D supplementation, intake or status (25‐hydroxy‐vitamin D) during pregnancy on perinatal and infant health outcomes. Data from trials and observational studies isolating the effect of vitamin D supplementation and intake were extracted and study quality was evaluated. Meta‐analysis was used to pool effect estimates. We identified five randomised trials with outcomes of relevance to our review. All had small sample size and dosage amount, duration and frequency varied as did the ability to correct deficiency. Pooled analysis of trials using fixed‐effects models suggested protective effects of supplementation on low birthweight (three trials, risk ratio (RR) = 0.40 [95% confidence interval (CI) 0.23, 0.71]) and non‐significant but suggestive effects of daily supplementation on small‐for‐gestational age (two trials, RR = 0.67 [0.40, 1.11]). No effect on preterm delivery (<37 weeks) was evident (two trials, RR = 0.77 [0.35, 1.66]). Little evidence from trials exists to evaluate the effect of vitamin D supplementation during pregnancy on maternal, perinatal or infant health outcomes. Based on both trials and observational studies, we recommend that future research explore small‐for‐gestational age, preterm delivery, pre‐eclampsia, and maternal and childhood infections, as outcomes of interest. Trials should focus on populations with a high prevalence of vitamin D deficiency, explore the relevance of timing of supplementation, and the dosage used in such trials should be sufficient to correct deficiency.
Is it Time to Replace Iron Folate Supplements in Pregnancy with Multiple Micronutrients?
Authors: Bhutta Zulfiqar A. , Imdad Aamer , Ramakrishnan Usha , Martorell Reynaldo
Published: June 2012

Anaemia is one of the most resilient global public health problems and affects a staggering 1.62 billion of the world's population, largely concentrated in Asia and Africa. Anaemia contributes to almost 120 000 maternal deaths globally and indirectly to almost a fifth (18%) of the burden of maternal mortality. Given the widespread prevalence of micronutrient deficiencies in developing countries, supplementation with multiple micronutrients rather than iron folate alone, could be of potential benefit to the mother and the fetus. This review evaluates the evidence of the impact of multiple micronutrient supplements during pregnancy, in comparison with standard iron folate supplements, on maternal anaemia. A systematic review of randomised controlled trials was conducted using search engines like PubMed, the Cochrane Library and World Health Organization Regional Databases. Primary outcomes were ‘maternal anaemia’ and ‘haemoglobin level’. We included seven studies for detailed data abstraction. There was no differential benefit of multiple micronutrients as compared with iron folate on maternal anaemia in the third trimester (relative risk = 1.03 [95% confidence interval 0.94, 1.12]). Results were similar for haemoglobin levels. In summary, multiple micronutrients have a similar effect on maternal anaemia compared with iron folate supplementation. These findings have to be interpreted in the context of other benefits of multiple micronutrient supplementation such as promoting better fetal growth and the possible increased risk of neonatal and perinatal mortality that are best resolved through large‐scale effectiveness trials.
Severe thrombocytopenia and patterns of bleeding in neonates: results from a prospective observational study and implications for use of platelet transfusions
Authors: Muthukumar P. , Venkatesh V. , Curley A. , Kahan B. C. , Choo L. , Ballard S. , Clarke P. , Watts T. , Roberts I. , Stanworth S. ,   for the Platelets Neonatal Transfusion Study Group
Published: June 2012

Objective

To describe patterns of clinical bleeding in neonates with severe thrombocytopenia (ST and platelet count <60 × 109 L−1), and to investigate the factors related to bleeding.

Study design

Seven tertiary‐level neonatal units enrolled neonates (n = 169) with ST. Data were collected prospectively on all clinically apparent haemorrhages. Relationships between bleeding, platelet count and baseline characteristics were explored through regression analysis.

Results

Bleeding was recorded in most neonates with ST (138/169; 82%), including 123 neonates with minor bleeding and 15 neonates with major bleeding. The most common sites of minor bleeding were from the renal tract (haematuria 40%), endotracheal tube (21%), nasogastric tube (10%) and skin (15%). Gestational age <34 weeks, development of ST within 10 days of birth and necrotizing enterocolitis were the strongest predictors for an increased number of bleeding events. For neonates with ST, a lower platelet count was not a strong predictor of increased bleeding.

Conclusions

The majority of neonates with ST bleed, although most episodes are minor. These findings establish the importance of clinical factors for bleeding risk, rather than minimum platelet count. Further studies should assess the clinical significance of different types of minor bleed for neonatal outcomes, the predictive value of minor bleeding for major bleeding and the role of platelet transfusions in preventing bleeding.
Reassessment of HLA‐G isoform specificity of MEM‐G/9 and 4H84 monoclonal antibodies
Authors: Zhao L. , Teklemariam T. , Hantash B. M.
Published: June 2012

Human leukocyte antigen (HLA)‐G is a non‐classical HLA class I molecule thought to play a key role in maternal‐fetal tolerance. Although initial studies suggested that HLA‐G expression is restricted to extravillous cytotrophoblasts, expression was subsequently reported in a wide variety of other human tissues and tumor cells. However, consensus as to the validity of these collective findings has proven difficult because the antibodies used to define the temporal and spatial expression patterns of HLA‐G remain incompletely characterized. The aim of our study was to reassess two of the most widely used HLA‐G antibodies (MEM‐G/9 and 4H84) in HLA‐G‐positive (JEG‐3 and HLA‐G transduced) and ‐negative (dermal fibroblast, mesenchymal stem cell, K562, and Jurkat) lines using flow cytometry, immunofluorescence, and western blotting. We found that MEM‐G/9 recognized HLA‐G3 by flow cytometry, indicating that its epitope is present on the α1 domain of HLA‐G. Although 4H84 preferably recognized unfolded HLA‐G‐free chains, it showed strong non‐specificity under certain methodological conditions.
Maize Hybrid Variability for Transpiration Decrease with Progressive Soil Drying
Authors: Gholipoor M. , Sinclair T. R. , Raza M. A. S. , Löffler C. , Cooper M. , Messina C. D.
Published: June 2012

Drought is ubiquitous in rainfed cropping systems and often limits maize yields. The sensitivity of transpiration response early in progressive soil drying is a trait with potential to improve crop drought resistance. Simulation studies demonstrated that increased sensitivity to drying soil leading to restricted transpiration rates results in conservation of soil water during vegetative stages for possible use during grain filling. In contrast to other crops, there have been no studies characterizing genotypic variability for this trait in maize. Experiments in controlled environments were conducted to characterize the fraction of transpirable soil water (FTSW) threshold on drying soil for 36 hybrids selected for variation in the field for drought resistance, regions of adaptation and stay green. While FTSW thresholds varied among hybrids from 0.60 to 0.33, these thresholds were not uniformly associated with level of drought resistance in the field. Nevertheless, this study demonstrated a high FTSW threshold corresponded with drought resistance observed in some modern maize germplasm (hybrids #7, 17, 24, 27 and 32). This knowledge can enable breeding work seeking to exploit this adaptive trait to improved drought tolerance in low threshold FTSW germplasm.
Assessment of in vitro digestibility and fermentation parameters of alfalfa hay‐based diet following direct incorporation of fenugreek seed (Trigonella foenum) and asparagus root (Asparagus officinalis)
Authors: Naseri V. , Hozhabri F. , Kafilzadeh F.
Published: June 2012

This study was completed to evaluate the effect of fenugreek seed (Trigonella foenum; FS) and asparagus root (Asparagus officinalis; AR) on in vitro nutrient digestibility and fermentation patterns. Different levels [0%, 5%, 10%, 15% and 20% of dry matter (DM)] of the medicinal plants were included using alfalfa hay (AH) as a basal substrate at different incubation times (12, 18, 24 and 48 h). Total phenolic components of AH, FS and AR were 5.9, 10 and 8.3 g/kg DM, whereas total tannins were 0.4, 3.8 and 1.5 g/kg DM, respectively. Corresponding values for saponins were 10.4, 27.3 and 40.3 g/kg DM. Fenugreek seed increased (p < 0.05) in vitro organic matter (OM) digestibility at different incubation times and decreased (p < 0.05) crude protein (CP) digestibility at 18 and 24 h of incubation. Asparagus root also increased (p < 0.05) in vitro OM digestibility and decreased (p < 0.05) CP digestibility at different incubation times. Neutral detergent fibre digestibility was increased (p < 0.05) by the addition of AR or FS at low levels, but decreased (p < 0.05) noticeably by increasing level of two plants in the basal substrate. Ammonia‐N concentration was markedly reduced (p < 0.05) by the addition of AR at different incubation times, and this reduction was accompanied by the decrease in CP digestibility. True DM degradability and partitioning factor (ratio of substrate DM truly degraded to gas volume produced at different times of incubation) were increased, and total volatile fatty acid concentration and total gas production were decreased (p < 0.05) with the addition of FS (at 10% and 15% DM levels) or AR (at 5%, 10% and 15% DM levels) at different incubation times. Results suggest that FS and AR may have potential as feed additives to increase the efficiency of nutrients’ utilization, particularly of nitrogen in ruminant diets.