bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of heat shock, heat exposure pattern, and heat hardening on survival of the sycamore lace bug, Corythucha ciliata
Authors: Ju Rui‐Ting , Chen Gen‐Bao , Wang Feng , Li Bo
Published: October 2011

The sycamore lace bug, Corythucha ciliata (Say) (Hemiptera: Tingidae), is an invasive exotic pest on Platanus trees in China. This study assessed the thermotolerance of C. ciliata in the laboratory. Detailed experiments were conducted on the effects of high temperature (35, 37, 39, 41, 43, and 45 °C), duration of exposure (0.5, 1, 2, 4, 6, and 8 h), and developmental stage (egg, nymph, and adult) on survival of the bug. Meanwhile, the effects of heat hardening on survival at lethal temperature (exposure to 33, 35, 37, 39, and 41 °C for 1 h prior to transfer to 43 °C for 2 h) were also assessed for nymphs and adults. Survival of eggs, nymphs, and adults was not affected by temperatures between 35 and 39 °C, but declined rapidly with increasing duration of exposure (from 0.5 to 8 h) at temperatures ≥41 °C. The lethal temperature that caused mortality of 50% (Ltemp50) of all developmental stages decreased with increasing duration of exposure from 0.5 to 8 h. The Ltemp50 for nymphs was 44.3, 42.0, and 39.0 °C after 0.5, 2, and 8 h exposure, respectively. Thermotolerance was the highest in eggs, followed by adults and then nymphs. Thermotolerance was slightly greater for adult males than for adult females. The ability of nymphs, females, and males to survive exposure to 43 °C for 2 h significantly increased by heat hardening, i.e., by exposure to a non‐lethal high temperature for 1 h; the optimal heat‐hardening temperature was 37 °C. The results indicate that survival of C. ciliata at heat‐shock temperatures depended on both the temperature and the duration of exposure, and the tolerance to heat shock was enhanced by heat hardening. The thermotolerance of C. ciliata may partially explain why C. ciliata has been rapidly spreading on Platanus trees in southern provinces of China.
Gonococcal infection in symptomatic and asymptomatic persons seeking medical clinics in Sofia – A 3‐year study 2008–2010
Authors: OUZOUNOVA‐RAYKOVA VESSELA , JORDANOV DANIEL , EL‐TIBI MOHAMED , MITOV IVAN
Published: October 2011

Ouzounova‐Raykova V, Jordanov D, El‐Tibi M, Mitov I. Gonococcal infection in symptomatic and asymptomatic persons seeking medical clinics in Sofia. A 3‐year study 2008–2010. APMIS 2011; 119: 864–7.

The aim was to determine the prevalence of gonococcal infection and to compare the results with those received by other researchers, because in Bulgaria a good medical practice for the laboratory confirmation, report and therapy is lacking. A total of 617 specimens from symptomatic and asymptomatic persons attending clinics in Sofia from January 2008 to December 2010 were tested by culture and in‐house PCR. Using PCR Neisseria gonorrhoeae was identified in six urethral (6.25%) and eight (1.54%) cervical specimens. By applying culture method, N. gonorrhoeae positive result was found in 12 swabs – one cervical and one urethral swab less. The positive results correspond predominantly to persons with genital complains and suspicions for gonococcal or other sexually transmitted infection. This is the first study in Bulgaria since 1989 and determines the prevalence of N. gonorrhoeae to 2.3% over a 3‐year period. Detection by culture was slightly less sensitive than by nucleic acid amplification test (NAAT). Continuous monitoring of gonorrhea by culture and NAAT is important for public health in Bulgaria.
Functional structure of an arid steppe plant community reveals similarities with Grime's C‐S‐R theory
Authors: Frenette‐Dussault Cédric , Shipley Bill , Léger Jean‐François , Meziane Driss , Hingrat Yves
Published: October 2011

Questions

(1) How do community‐weighted mean (CWM) trait values of 23 functional traits measured on 34 plant species vary along a gradient of aridity under grazed and ungrazed conditions in an arid steppe? (2) How does variation in our CWM trait values differ from those of more mesic grasslands?

Location

Eastern Morocco.

Methods

We measured relative abundance and functional traits along a short aridity gradient over two consecutive years at five heavily grazed sites, each with an exclosure preventing grazing. We analysed the relationship between aridity, grazing, and the expression of CWM trait values using ordination methods and a fourth‐corner analysis.

Results

Unconstrained and constrained ordinations identified three distinct suites of temporally consistent functional traits that co‐varied with aridity and grazing, and the fourth‐corner analysis identified a number of significant but weak trait–environment associations. Grazing selected for short, fast‐growing annual species with high SLA, high pastoral value and low seed mass, while aridity selected for species possessing succulent leaves with high δ13C leaf content, spines, low LDMC and short stature, although the relative importance of precipitation and grazing changed between years.

Conclusions

Although distinct from more mesic grasslands, our study sites exhibited patterns of trait correlations that were similar to the worldwide leaf economics spectrum. These correlation patterns represented three groups that were reminiscent of Grime's C‐S‐R model. Direct ordinations supported this interpretation. Temporal variation in our results was due in part to precipitation fluctuations. Our results also indicated selection for a grazing avoidance strategy under heavy grazing. Integrating plant functional traits in conservation and management of arid ecosystems represents a novel and challenging task to ensure more sustainable use of these lands.
Repeated Ethanol but not Phencyclidine Impairs Spontaneous Alternation Behaviour in the Y‐Maze
Authors: Götesson Joacim , Ericson Mia , Söderpalm Bo , Pickering Chris
Published: October 2011

Abstract:  Prolonged consumption of ethanol produces prefrontal cortex (PFC) dysfunction in patients, and this has been demonstrated using structural, physiological and psychological measurements. We therefore wanted to develop an animal model of PFC dysfunction to study whether this state changes sensitivity for ethanol or other behavioural/motivational measures. Adolescent Wistar rats were first screened in the novel object recognition task to establish a pre‐treatment baseline measure of locomotor activity, anxiety‐like behaviour and PFC function. Animals were divided into four treatment groups [saline, 5 mg/kg phencyclidine (PCP), 2.5g/kg ethanol, ethanol + PCP] and injected i.p. for 5 days followed by a 2‐day washout. On the 8th day, animals were allowed to explore a Y‐maze for 10 min. and spontaneous alternations were recorded using the ANY‐maze tracking system. PCP, a classic drug used to induce PFC dysfunction in animals, did not significantly reduce the % correct alternations relative to the 70% level achieved by the saline group. Ethanol and the combination of Ethanol + PCP, however, significantly reduced alternations to approximately 30%. The combined dose was not additive in terms of Y‐maze impairment, and these animals had less total distance travelled and greater time immobile relative to the other groups. We therefore concluded that injection of 2.5 g/kg ethanol for 5 days in Wistar rats produces a more substantial, consistent and valid PFC dysfunction than 5 mg/kg PCP.
Hopefulness Among Non‐U.S.‐Born Latino Youth and Young Adults
Authors: Stoddard Sarah A. , Garcia Carolyn M.
Published: October 2011

PROBLEM:  U.S. Latino youths experience disproportionately high rates of health and social problems. There is a need to identify protective factors for reducing risky behaviors. Little is known about the protective nature of hope among immigrant Latino adolescents.

METHODS:  This descriptive cross‐sectional study examined hope and expectations for the future in non‐U.S.‐born Latino adolescents and young adults (n= 98) in urban and rural areas in the midwestern United States.

FINDINGS:  Participants reported feeling hopeful about their future; however, differences were detected among subgroups.

CONCLUSION:  Findings affirm the potential of hope as a protective factor for immigrant Latino adolescents and young adults. Nurses should be aware of hopefulness when implementing mental health preventive interventions. Research is needed to identify effective mechanisms for promoting and sustaining hope.
Vitellogenin content in fat body and ovary homogenates of workers and queens of Melipona quadrifasciata anthidioides during vitellogenesis
Authors: Paes de Oliveira Vagner Tadeu , Berger Bruno , Cruz‐Landim Carminda da , Simões Zilá Luz Paulino
Published: October 2011

Abstract  Vitellogenin (Vg) is an egg yolk protein that is produced primarily in the fat body of most female insects. In the advanced social structure of eusocial honeybees, the presence of the queen inhibits egg maturation in the workers’ ovaries. However in the stingless bee Melipona quadrifasciata, the workers always develop ovaries and lay a certain amount of eggs while provisioning the brood cells with larval food during what is known as the worker nurse phase. The present work is a comparative study of the presence of Vg in homogenates of the fat bodies and ovaries of the nurse workers, and the virgin and physogastric queens of M. quadrifasciata. The presence of Vg was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting using Apis mellifera anti‐egg antibody. Vg was not detected in the fat bodies or ovaries of the workers, but it was found in the ovaries of virgin and physogastric queens and in the fat body of physogastric queens. The results are discussed, taking into account the reproductive state of the individuals and the other possible roles of Vg, such as a storage protein for metoabolism of other organs.
Validation of reference genes for gene expression studies in the emerald ash borer (Agrilus planipennis)
Authors: Rajarapu Swapna Priya , Mamidala Praveen , Mittapalli Omprakash
Published: October 2011

Abstract  The Emerald ash borer (EAB, Agrilus planipennis Fairmaire) an exotic invasive insect pest has killed millions of ash trees (Fraxinus spp.) across North America and threatens billions more. We validated six A. planipennis reference genes (actin, ACT; beta tubulin, β‐TUB; glyceraldehyde‐3‐phosphate dehydrogenase, GAPDH; ribosomal protein, RPL7; translation elongation factor 1α, TEF‐1α; and ubiquitin, UBQ) using geNorm, Normfinder and BestKeeper for accurate determination of target messenger RNA levels in gene expression studies. The stability of the six reference genes was evaluated in different larval tissues, developmental stages and two treatments of A. planipennis using quantitative real‐time polymerase chain reaction. Although there was no consistent ranking observed among the reference genes across the samples, the overall analysis revealed TEF‐1α as the most stable reference gene. GAPDH and ACT showed least stability for all the samples studied. We conclude that TEF‐1α is the most appropriate reference gene for gene expression studies in A. planipennis. Results obtained can be applicable for transcript profiling in other invasive insect pests. Further, these validated reference genes could also serve as the basis for selection of candidate reference genes in any given insect system post‐validation.
HOW TO DEMONSTRATE RIGOR WHEN PRESENTING GROUNDED THEORY RESEARCH IN THE SUPPLY CHAIN MANAGEMENT LITERATURE
Authors: KAUFMANN LUTZ , DENK NIKOLA
Published: October 2011

Researchers have found that supply chain management (SCM) studies that employ inductive approaches lack a common structure and often fail to adequately describe their research process and methodology. The purpose of this article is to increase rigor in SCM research by deriving an interpretive structure of presenting grounded theory (GT) studies. The structure presented in this article allows researchers to clearly demonstrate the rigor and validity of their methodology, and to thus increase the confidence of reviewers and fellow SCM researchers in their findings.
George III and Parliament*
Authors: DICKINSON H.T.
Published: October 2011

Circumstances were auspicious when George III came to the throne in 1760, but soon his political actions were much criticized and he was accused from early in his reign until well into the 20th century of weakening the independence of parliament and undermining the constitution. Some contemporaries did defend him and these views received powerful support from Sir Lewis Namier and his followers in the 20th century. Both interpretations have their flaws, however, because of the failure to recognize the profound changes in the context in which George acted over his long reign and the subtle changes that occurred in Britain's unwritten constitution over that half century. By examining how the king appointed and dismissed ministers, sought to influence the composition of both houses of parliament, and endeavoured to shape government policy, this article seeks to revise our understanding of the king's relations with parliament and the constitution and to relocate our overall assessment of him between those offered by his many critics and defenders both during his reign and long afterwards.
In Search of ‘Affectionate Regard’: American Merchant Lobbies and the State during the Atlantic Imperial Crisis*
Authors: KIM DAERYOON
Published: October 2011

This article revisits the politics of British merchants trading to North America in the period between 1763 and 1783. Their political success and failure in this critical period have been examined primarily in terms of their impact on the escalation of imperial crisis, with the day‐to‐day operation of merchant politics rarely taken into full account. This article takes an alternative approach of studying the political influence of merchants trading to North America within the context of their interaction with the state. By looking into the organisation, the process of lobbying, and the arguments that the merchants adopted, the article highlights how, in response to many sources of tension and uncertainty inherent within their relationship with the state, they demarcated their own areas of contribution to the shaping of commercial and colonial policy. Through the case study of merchants trading to North America, this article sheds further light on the necessity to understand the evolution of such modern political institutions as commercial lobbies in their specific economic and political contexts.
‘A Rather Novel Constitutional Experiment’: The Formation of the 1977–8 ‘Lib‐Lab Pact’
Authors: DOREY PETER
Published: October 2011

By March 1977, the Labour government which had narrowly been re‐elected in the October 1974 election, had lost its parliamentary majority, and was facing a vote of confidence tabled by the Conservative opposition. Senior Labour figures thus desperately sought to secure support from one of the minor parties. Unable to broker a deal with either the Ulster Unionists or the Scottish National Party (SNP), largely due to ideological differences, the Labour leadership entered into negotiations with the Liberal leader, David Steel. The result was that the Liberal Party agreed to provide the Labour government with parliamentary support, in return for consultation, via a joint committee, over future policies, coupled with the reintroduction of devolution legislation, and a pledge to provide for direct elections for the European parliament (ideally using some form of proportional representation). There was some surprise that Steel had not pressed for more, or stronger, policy commitments or concessions from the Labour prime minister, James Callaghan, but Steel was thinking long term; he envisaged that Liberal participation in the joint consultative committee would foster closer co‐operation between Liberals and Labour moderates/social democrats, and eventually facilitate a realignment of British politics by marginalising both the Labour left, and the increasingly right‐wing Conservatives Party.
Preparation and Properties of Polypropylene/Clay Nanocomposites for Food Packaging
Authors: Choi Ri‐Na , Cheigh Chan‐Ick , Lee Sun‐Young , Chung Myong‐Soo
Published: October 2011

Abstract:  Polypropylene (PP)/clay nanocomposites based on PP, organic clay (montmorillonite; MMT), and maleated polypropylene (MAPP) were prepared by melt compounding. The mechanical, thermal, morphological, and gas barrier properties of the resulting PP/clay nanocomposites were investigated at varying concentrations of the components for food packaging. The results revealed that the mechanical strengths, including tensile, flexural, and Izod impact strength, were increased for PP/clay nanocomposites compared to neat PP. The thermal properties showed a tendency for the melting and degradation temperatures to increase with the clay concentration. The effect of the compatibilizer was observed using scanning electron microscopy (SEM). The X‐ray diffraction pattern of the nanocomposites revealed increased d‐spacing of the MMT layers, indicating that the compatibility of neat PP and clay was improved by the addition of MAPP, and the intercalation and partial exfoliation of the layers. The use of clay increased the mobility distance of the gas molecules, leading to the oxygen permeability of neat PP being reduced by 26% to 55%.
Survey of 1,2‐Dicarbonyl Compounds in Commercial Honey of Different Floral Origin
Authors: Arena Elena , Ballistreri Gabriele , Tomaselli Filippo , Fallico Biagio
Published: October 2011

Abstract:  In this study we conducted a survey of the concentrations of the major 1,2‐dicarbonyl compounds in 40 commercial honey samples from 12 different floral origins. 3‐Deoxyglucosone (3‐DG), glyoxal (GO), and methylglyoxal (MGO) were measured, using their corresponding quinoxaline derivatives, by high‐performance liquid chromatography (HPLC). The analytical performance of the HPLC method for the analysis of 1,2‐dicarbonyl compounds was evaluated in terms of linearity, limits of detection (LODs), limits of quantification (LOQs), and precision. Linearity over 2 orders of magnitude, LODs (0.01–0.04 mg/kg), and LOQs (0.03–0.12 mg/kg) were calculated. Instrumental precision, as measured by the repeatability relative standard deviation% (RSDr%), was found to be between 0.22% and 0.55%. Furthermore, the concentrations of factors GO and MGO with respect to 3‐DG were also calculated for rapid quantification in honey. In honey samples, the concentrations of 3‐DG ranged from 75.9 to 808.6 mg/kg and were significantly higher (up to 100‐fold) than those of 5‐hydroxymethylfurfural (HMF). Values for GO and MGO were 0.1–10.9 and 0.2–2.9 mg/kg, respectively. The chemical characteristics that most influenced the levels of 1,2‐dicarbonyl compounds in honey were found to be pH and total phenols. This was supported by multivariate analysis used to classify different honey types with respect to their chemical characteristics. In addition, both dicarbonyls and phenols are believed to contribute to the development of the final color of honey.
Optimization of Consumer Acceptability and Sensory Characteristics for Marinated Broiler Breast Meat
Authors: Lee Y.S. , Youm G. , Owens C.M. , Meullenet J.F.
Published: October 2011

Abstract:  In the present study, the effects of marination on the quality of poultry breast meat deboned at various times postmortem (PM) were investigated. One of the specific goals was to optimize the processing conditions between deboning time, tumbling duration, and poultry breast meat tenderness, with the objective of developing specific recommendations on processing practices adopted by the poultry industry. Broiler breast (Pectoralis major) muscles deboned at 0.25, 1.5, 3, 6, and 24 h PM were vacuum tumbled with 20% solution added containing 1% salt and 0.45% sodium tripolyphosphate for either 15 or 30 min. Meat quality measurements including marination uptake, retention, cooking loss, instrumental texture, sensory descriptive analysis, and consumer acceptance were performed. Results indicated that acceptable tenderness was achieved for marinated treatments deboned at 3 h or later PM. Fillets deboned at shorter PM were rated tough by consumers. Marination duration had very little effect on the quality of the meat processed.

Practical Application:  For the poultry industry to maximize consumer acceptance for marinated broiler breast meat, this research will be of benefit. Various qualities of broiler breast meat such as tenderness and water‐holding capacities were examined under different marination conditions.
Characterization of the Pulp and Kernel Oils from Syagrus oleracea, Syagrus romanzoffiana, and Acrocomia aculeata
Authors: Coimbra Michelle Cardoso , Jorge Neuza
Published: October 2011

Abstract:  Vegetable oils are important sources of essential fatty acids. It is, therefore, important to characterize plant species that can be used as new oil sources. This study aimed to characterize the oils from guariroba (Syagrus oleracea), jerivá (Syagrus romanzoffiana), and macaúba (Acrocomia aculeata). The physicochemical characterization was performed using official analytical methods for oils and fats, free fatty acids, peroxide value, refractive index, iodine value, saponification number, and unsaponifiable matter. The oxidative stability was determined using the Rancimat at 110 °C. The fatty acid composition was performed by gas chromatography. The results were submitted to Tukey's test for the medium to 5% using the ESTAT program. The pulp oils were more unsaturated than kernel oils, as evidenced by the higher refractive index and iodine value, especially the macaúba pulp oil which gave 1.4556 and 80 g I2/100 g, respectively, for these indices. The kernel oils were less altered by oxidative process and had high induction period, free fatty acids below 0.5%, and peroxide value around 0.19 meq/kg. The guariroba kernel oil showed the largest induction period, 91.82 h.

Practical Application:  The vegetable oils, besides being consumed directly as food, are important raw material for the chemical, pharmaceutical, and food industries. In recent years, the world market of vegetable oils has been characterized by stronger growth of demand over supply. Several species of palm trees are shown to be promising sources of oils. The characterization of oils extracted from some species, such as guariroba, jerivá, and macaúba, has not yet been fully elucidated. For this reason, it becomes important to investigate the physicochemical characterization of these oils, aiming at a possible use in food or in the industry.
Wild Buckwheat Is Unlikely to Pose a Risk to Buckwheat‐Allergic Individuals
Authors: Nordlee Julie A. , Panda Rakhi , Baumert Joseph L. , Goodman Richard E. , Taylor Steve L.
Published: October 2011

Abstract:  Buckwheat (Fagopyrum esculentum) is a commonly allergenic food especially in Asia where buckwheat is more commonly consumed. Wild buckwheat (Polygonum convolvulus, recently changed to Fallopia convolvulus) is an annual weed prevalent in grain‐growing areas of the United States. Wild buckwheat is not closely related to edible buckwheat although the seeds do have some physical resemblance. A large shipment of wheat into Japan was halted by the discovery of the adventitious presence of wild buckwheat seeds over possible concerns for buckwheat‐allergic consumers. However, IgE‐binding was not observed to an extract of wild buckwheat using sera from 3 buckwheat‐allergic individuals either by radio‐allergosorbent test inhibition or by immunoblotting after protein separation by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Furthermore, the extract of wild buckwheat was not detected in a buckwheat enzyme‐linked immunosorbent assay developed with antisera against common buckwheat. Thus, wild buckwheat is highly unlikely to pose any risk to buckwheat‐allergic individuals. The common names of plants should not be a factor in the risk assessment for possible cross‐allergenicity.
Water Vapor Adsorption Isotherms of Agar‐Based Nanocomposite Films
Authors: Rhim Jong‐Whan
Published: October 2011

Abstract:  Adsorption isotherms of agar and agar/clay nanocomposite films prepared with different types of nanoclays, that is, a natural montmorillonite (Cloisite Na+) and 2 organically modified montmorillonites (Cloisite 30B and Cloisite 20A), were determined at 3 different temperatures (10, 25, and 40 °C). The water vapor adsorption behavior of the nanocomposite films was found to be greatly influenced with the type of clay. The Guggenheim–Anderson–de Boer (GAB) isotherm model parameters were estimated by using both polynomial regression and nonlinear regression methods and it was found that the GAB model fitted adequately for describing experimental adsorption isotherm data for the film samples. The monolayer moisture content (mo) of the film samples was also greatly affected by the type of nanoclay used, that is, mo of nanocomposite films was significantly lower than that of the neat agar film. Nanocomposite films prepared with hydrophobic nanoclays (Cloisite 30B and Cloisite 20A) exhibited lower mo values than those prepared with hydrophilic nanoclay (Cloisite Na+).
Autonomy and Relatedness Revisited: Cultural Manifestations of Universal Human Needs
Authors: Keller Heidi
Published: October 2011

Abstract— Autonomy and relatedness are considered basic human needs that manifest differently in different cultural environments in response to contextual demands. This article conceptualizes 3 types of cultural environments—prototypical Western, urban, middle‐class families; prototypical rural, subsistence‐based farming families; and a hybrid milieu of urban middle‐class families from non‐Western environments—and proposes that autonomy and relatedness have different meanings in each type. In contexts in which individuals have a high degree of formal education (Western and non‐Western middle‐class families), there is an emphasis on inner states and mental representations. Western middle‐class families focus on separate individuals; non‐Western middle‐class families focus on the family as a social unit. In contexts in which individuals have a low degree of formal education, there is a primary emphasis on social responsibilities. Different socialization strategies support adaptive frameworks in each of the 3 types of contexts: individual psychological autonomy in Western middle‐class families, communal psychological autonomy in non‐Western middle‐class families, and action autonomy in subsistence‐based farming families. All conceptions of autonomy and relatedness can be considered as universal competencies, yet they are differently emphasized in different cultural milieus due to differing contextual demands.
De novo transcriptome assembly and polymorphism detection in the flowering plant Silene vulgaris (Caryophyllaceae)
Authors: SLOAN DANIEL B. , KELLER STEPHEN R. , BERARDI ANDREA E. , SANDERSON BRIAN J. , KARPOVICH JOHN F. , TAYLOR DOUGLAS R.
Published: October 2011

Members of the angiosperm genus Silene are widely used in studies of ecology and evolution, but available genomic and population genetic resources within Silene remain limited. Deep transcriptome (i.e. expressed sequence tag or EST) sequencing has proven to be a rapid and cost‐effective means to characterize gene content and identify polymorphic markers in non‐model organisms. In this study, we report the results of 454 GS‐FLX Titanium sequencing of a polyA‐selected and normalized cDNA library from Silene vulgaris. The library was generated from a single pool of transcripts, combining RNA from leaf, root and floral tissue from three genetically divergent European subpopulations of S. vulgaris. A single full‐plate 454 run produced 959 520 reads totalling 363.6 Mb of sequence data with an average read length of 379.0 bp after quality trimming and removal of custom library adaptors. We assembled 832 251 (86.7%) of these reads into 40 964 contigs, which have a total length of 25.4 Mb and can be organized into 18 178 graph‐based clusters or ‘isogroups’. Assembled sequences were annotated based on homology to genes in multiple public databases. Analysis of sequence variants identified 13 432 putative single‐nucleotide polymorphisms (SNPs) and 1320 simple sequence repeats (SSRs) that are candidates for microsatellite analysis. Estimates of nucleotide diversity from 1577 contigs were used to generate genome‐wide distributions that revealed several outliers with high diversity. All of these resources are publicly available through NCBI and/or our website (http://silenegenomics.biology.virginia.edu) and should provide valuable genomic and population genetic tools for the Silene research community.
Human investigations into the arterial and cardiopulmonary baroreflexes during exercise
Authors: Fadel Paul J. , Raven Peter B.
Published: October 2011

After considerable debate and key experimental evidence, the importance of the arterial baroreflex in contributing to and maintaining the appropriate neural cardiovascular adjustments to exercise is now well accepted. Indeed, the arterial baroreflex resets during exercise in an intensity‐dependent manner to continue to regulate blood pressure as effectively as at rest. Studies have indicated that the exercise resetting of the arterial baroreflex is mediated by both the feedforward mechanism of central command and the feedback mechanism associated with skeletal muscle afferents (the exercise pressor reflex). Another perhaps less appreciated neural mechanism involved in evoking and maintaining neural cardiovascular responses to exercise is the cardiopulmonary baroreflex. The limited information available regarding the cardiopulmonary baroreflex during exercise provides evidence for a role in mediating sympathetic nerve activity and blood pressure responses. In addition, recent investigations have demonstrated an interaction between cardiopulmonary baroreceptors and the arterial baroreflex during dynamic exercise, which contributes to the magnitude of exercise‐induced increases in blood pressure as well as the resetting of the arterial baroreflex. Furthermore, neural inputs from the cardiopulmonary baroreceptors appear to play an important role in establishing the operating point of the arterial baroreflex. This symposium review highlights recent studies in these important areas indicating that the interactions of four neural mechanisms (central command, the exercise pressor reflex, the arterial baroreflex and cardiopulmonary baroreflex) are integral in mediating the neural cardiovascular adjustments to exercise.
Anoctamins and gastrointestinal smooth muscle excitability
Authors: Sanders Kenton M. , Zhu Mei Hong , Britton Fiona , Koh Sang Don , Ward Sean M.
Published: October 2011

Interstitial cells of Cajal (ICC) generate electrical pacemaker activity in gastrointestinal smooth muscles. We investigated whether Tmem16a, which encodes anoctamin 1 (ANO1), a Ca2+‐activated Cl− channel, might be involved in pacemaker activity in ICC. The Tmem16a transcripts and ANO1 were expressed robustly in GI muscles, specifically in ICC in murine, non‐human primate (Macaca fascicularis) and human GI tracts. Splice variants of Tmem16a, as well as other paralogues of the Tmem16 family, were expressed in gastrointestinal muscles. Calcium‐activated Cl− channel blocking drugs, niflumic acid and DIDS blocked slow waves in intact muscles of mouse, primate and human small intestine and stomach. Slow waves failed to develop in Tmem16a knock‐out mice (Tmem16atm1Bdh/tm1Bdh). The pacemaker mechanism was investigated in isolated ICC from transgenic mice with constitutive expression of copepod super green fluorescent protein (copGFP). Depolarization of ICC activated inward currents due to a Cl−‐selective conductance. Removal of extracellular Ca2+, replacement of Ca2+ with Ba2+, or extracellular Ni2+ (30 μm) blocked the inward current. Single Ca2+‐activated Cl− channels with a unitary conductance of 7.8 pS were resolved in excised patches from ICC. The inward current was blocked in a concentration‐dependent manner by niflumic acid (IC50= 4.8 μm). The role of ANO1 in cholinergic responses in ICC was also investigated. Carbachol activated Ca2+‐activated Cl− currents in ICC, and responses to cholinergic nerve stimulation were blocked by niflumic acid in intact muscles. Anoctamin 1 is a prominent conductance in ICC, and these channels appear to be involved in pacemaker activity and in responses to enteric excitatory neurotransmitters.
Synchronous Adjustment of Milling Tool Path Based on the Relative Deviation
Authors: Wan Xiao-Jin , Xiong Cai-Hua , Hua Lin
Published: October 2011

In machining process, machining accuracy of part mainly depends on the position and orientation of the cutting tool with respect to the workpiece which is influenced by errors of machine tools and cutter-workpiece-fixture system. A systematic modeling method is presented to integrate the two types of error sources into the deviation of the cutting tool relative to the workpiece which determines the accuracy of the machining system. For the purpose of minimizing the machining error, an adjustment strategy of tool path is proposed on the basis of the generation principle of the cutter location source file (CLSF) in modern computer aided manufacturing (CAM) system by means of the prediction deviation, namely, the deviation of the cutting tool relative to the workpiece in computer numerical control (CNC) machining operation. The resulting errors are introduced as adjustment values to adjust the nominal tool path points from cutter location source file from commercial CAM system prior to machining. Finally, this paper demonstrates the effectiveness of the prediction model and the adjustment technique by two study cases.
Theoretical analysis of the thread effect in helical TomoTherapy
Authors: Chen Mingli , Chen Yu , Chen Quan , Lu Weiguo
Published: October 2011

Purpose:

The longitudinal dose ripple on the off‐axis caused by helical radiation delivery, such as the TomoTherapy system, has been observed, and its relation with respect to pitch has been studied with empirically found optimal pitches, 0.86/n, by Kissick et al. [Med. Phys. 32, 1414–1423 (2005)]. This ripple artifact referred to as the thread effect is periodic in nature and is caused by various periodic factors. In this work, the factors that cause the thread effect were unveiled, including jaw profile divergence, the inverse square law, attenuation, and the cone effect, and their impact on the thread effect were studied.

Methods:

Mathematical formulation for individual and combined factors were set up. Based on theoretical analysis and simulations, optimal pitches that result in local minima of the ripple amplitude with respect to the jaw width and off‐axis distance were identified and verified. The effectiveness of optimization in reducing the thread effect were also studied.

Results:

Analysis and simulation based on the square‐shaped jaw profiles well characterize the thread effect. Simulations based on the real jaw profiles show reduced ripples and very good agreement of optimal pitches compared with those based on the square profiles. The optimal pitches were found to have little jaw width dependence, except for the real jaw profile of small width (1.05 cm). The optimal pitches for the real jaw profile of width 1.05 cm are unidentifiable except for the largest ones, due to the relative smoothness of the jaw profile. With optimized intensity modulation, the thread effect can be largely suppressed. For real jaw profiles, the optimal pitches with or without dose optimization do not change much. The numbers 0.86/n found by Kissick et al. well approximate the optimal pitches for off‐axis distance of 5 cm. However, optimal pitches are not universal for different off‐axis distances: they decrease as the off‐axis distance increases.

Conclusions:

The thread effect can be well explained by the proposed model. Optimization can largely reduce the thread effect. However, an optimal pitch reduces the ripple much easier especially when optimization is limited by many constraints. The optimal pitches predicted by the proposed model could be used as a reference for pitch selection regardless the tumor is at large or small off‐axis distance.
Genomics of the Proteorhodopsin-Containing Marine Flavobacterium Dokdonia sp. Strain MED134
Authors: González José M. , Pinhassi Jarone , Fernández-Gómez Beatriz , Coll-Lladó Montserrat , González-Velázquez Mónica , Puigbò Pere , Jaenicke Sebastian , Gómez-Consarnau Laura , Fernàndez-Guerra Antoni , Goesmann Alexander , Pedrós-Alió Carlos
Published: October 2011

Proteorhodopsin phototrophy is expected to have considerable impact on the ecology and biogeochemical roles of marine bacteria. However, the genetic features contributing to the success of proteorhodopsin-containing bacteria remain largely unknown. We investigated the genome of
Dokdonia
sp. strain MED134 (
Bacteroidetes
) for features potentially explaining its ability to grow better in light than darkness. MED134 has a relatively high number of peptidases, suggesting that amino acids are the main carbon and nitrogen sources. In addition, MED134 shares with other environmental genomes a reduction in gene copies at the expense of important ones, like membrane transporters, which might be compensated by the presence of the proteorhodopsin gene. The genome analyses suggest
Dokdonia
sp. MED134 is able to respond to light at least partly due to the presence of a strong flavobacterial consensus promoter sequence for the proteorhodopsin gene. Moreover,
Dokdonia
sp. MED134 has a complete set of anaplerotic enzymes likely to play a role in the adaptation of the carbon anabolism to the different sources of energy it can use, including light or various organic matter compounds. In addition to promoting growth, proteorhodopsin phototrophy could provide energy for the degradation of complex or recalcitrant organic matter, survival during periods of low nutrients, or uptake of amino acids and peptides at low concentrations. Our analysis suggests that the ability to harness light potentially makes MED134 less dependent on the amount and quality of organic matter or other nutrients. The genomic features reported here may well be among the keys to a successful photoheterotrophic lifestyle.
Malate-Mediated Carbon Catabolite Repression in Bacillus subtilis Involves the HPrK/CcpA Pathway
Authors: Meyer Frederik M. , Jules Matthieu , Mehne Felix M. P. , Le Coq Dominique , Landmann Jens J. , Görke Boris , Aymerich Stéphane , Stülke Jörg
Published: October 2011

Most organisms can choose their preferred carbon source from a mixture of nutrients. This process is called carbon catabolite repression. The Gram-positive bacterium
Bacillus subtilis
uses glucose as the preferred source of carbon and energy. Glucose-mediated catabolite repression is caused by binding of the CcpA transcription factor to the promoter regions of catabolic operons. CcpA binds DNA upon interaction with its cofactors HPr(Ser-P) and Crh(Ser-P). The formation of the cofactors is catalyzed by the metabolite-activated HPr kinase/phosphorylase. Recently, it has been shown that malate is a second preferred carbon source for
B. subtilis
that also causes catabolite repression. In this work, we addressed the mechanism by which malate causes catabolite repression. Genetic analyses revealed that malate-dependent catabolite repression requires CcpA and its cofactors. Moreover, we demonstrate that HPr(Ser-P) is present in malate-grown cells and that CcpA and HPr interact
in vivo
in the presence of glucose or malate but not in the absence of a repressing carbon source. The formation of the cofactor HPr(Ser-P) could be attributed to the concentrations of ATP and fructose 1,6-bisphosphate in cells growing with malate. Both metabolites are available at concentrations that are sufficient to stimulate HPr kinase activity. The adaptation of cells to environmental changes requires dynamic metabolic and regulatory adjustments. The repression strength of target promoters was similar to that observed in steady-state growth conditions, although it took somewhat longer to reach the second steady-state of expression when cells were shifted to malate.
Impaired blood pressure recovery to hemorrhage in obese Zucker rats with orthopedic trauma
Authors: Xiang Lusha , Lu Silu , Fuller William , Aneja Arun , Russell George V. , Jones Louis B. , Hester Robert
Published: October 2011

We have shown that obese Zucker rats with orthopedic trauma (OZT) exhibit a loss of arteriolar tone in skeletal muscle. We hypothesize that the loss of arteriolar tone in OZT blunts vasoconstrictor responses to hemorrhage, resulting in an impaired blood pressure recovery. Orthopedic trauma was induced with soft tissue injury and local injection of bone components in both hindlimbs in lean (LZT) and OZT (11–13 wk). One day after the orthopedic trauma, blood pressure responses following hemorrhage were measured in conscious control lean, control obese, LZT, and OZT. In another set of experiments, the spinotrapezius muscle of control and trauma animals was prepared for microcirculatory observation. Arteriolar responses to phenylephrine (PE) or hemorrhage were determined. Hemorrhage resulted in similar blood pressure responses in control animals and LZT, but the blood pressure recovery following hemorrhage was blunted in the OZT. In the spinotrapezius, OZT exhibited decreased arteriolar tone and blunted vasoconstrictor responses to PE and hemorrhage. Treatment with glibenclamide improved the blood pressure recovery in the conscious OZT and improved the arteriolar tone, and PE induced vasoconstriction in the spinotrapezius of the OZT. Thus, ATP-dependent K+ channel-mediated loss of arteriolar tone in OZT blunts the arteriolar constriction to hemorrhage, resulting in impaired blood pressure recovery.
Nestin+cells and healing the infarcted heart
Authors: Calderone Angelino
Published: October 2011

Scar formation following an ischemic insult to the heart is referred to as reparative fibrosis and represents an essential physiological response to heal the damaged myocardium. The biological events of reparative fibrosis include inflammation, the deposition of collagen by myofibroblasts, sympathetic innervation, and angiogenesis. Several studies have further reported that scar formation was associated with the recruitment of neural crest-derived cardiac resident nestin+cells that display characteristics consistent with a neural progenitor/stem cell phenotype. During the reparative fibrotic response, these nestin+cells participate in neural remodeling and represent a novel cellular substrate of angiogenesis. In addition, a subpopulation of nestin+cells identified in the normal heart expressed cardiac progenitor transcriptional factors and may directly contribute to myocardial regeneration following ischemic damage. Nestin protein was also detected in endothelial cells of newly formed blood vessels in the scar and may represent a marker of revascularization. Lastly, nestin was induced in a subpopulation of smooth muscle α-actin+scar-derived myofibroblasts, and the expression of the intermediate filament protein may provide a proliferative advantage. Collectively, these data demonstrate that diverse populations of nestin+cells participate in cardiac wound healing.
Tropomodulin Capping of Actin Filaments in Striated Muscle Development and Physiology
Authors: Gokhin David S. , Fowler Velia M.
Published: October 2011

Efficient striated muscle contraction requires precise assembly and regulation of diverse actin filament systems, most notably the sarcomeric thin filaments of the contractile apparatus. By capping the pointed ends of actin filaments, tropomodulins (Tmods) regulate actin filament assembly, lengths, and stability. Here, we explore the current understanding of the expression patterns, localizations, and functions of Tmods in both cardiac and skeletal muscle. We first describe the mechanisms by which Tmods regulate myofibril assembly and thin filament lengths, as well as the roles of closely related Tmod family variants, the leiomodins (Lmods), in these processes. We also discuss emerging functions for Tmods in the sarcoplasmic reticulum. This paper provides abundant evidence that Tmods are key structural regulators of striated muscle cytoarchitecture and physiology.
Hydrogel Synthesis Directed Toward Tissue Engineering: Impact of Reaction Condition on Structural Parameters and Macroscopic Properties of Xerogels
Authors: Adnadjević Borivoj , Jovanović Jelena
Published: October 2011

The existence of correlation and functional relationships between reaction conditions (concentrations of crosslinker, monomer and initiator, and neutralization degree of monomer), primary structural parameters (crosslinking density of network, average molar mass between crosslinks, and distance between macromolecular chains), and macroscopic properties (equilibrium swelling degree and xerogel density) of the synthesized xerogels which are important for application in tissue engineering is investigated. The structurally different xerogels samples of poly(acrylic acid), poly(methacrylic acid), and poly(acrylic acid-g-gelatin) were synthesized by applying different methods of polymerization: crosslinking polymerization, crosslinking polymerization in high concentrated aqueous solution, and crosslinking graft polymerization. The values of primary structural parameters and macroscopic properties were determined for the synthesized xerogels samples. For all of the investigated methods of polymerization, an existence of empirical power function of the dependence of primary structural parameters and macroscopic properties on the reaction conditions was established. The scaling laws between primary structural parameters and macroscopic properties on average molar mass between crosslinks were established. It is shown that scaling exponent is independent from the type of monomer and other reaction conditions within the same polymerization method. The physicochemical model that could be used for xerogel synthesis with predetermined macroscopic properties was suggested.
Anatomical Correlates to Nectar Feeding among the Strepsirrhines of Madagascar: Implications for Interpreting the Fossil Record
Authors: Muchlinski Magdalena N. , Perry Jonathan M. G.
Published: October 2011

One possible ecological scenario for the origin of primates is the archaic pollination and coevolution hypothesis. Its proponents contend that the consumption of nectar by some early primates and the resulting cross-pollination is an example of coevolution that drove adaptive radiations in some primates. This hypothesis is perhaps ecologically sound, but it lacks the morphology-behavior links that would allow us to test it using the fossil record. Here we attempt to identify cranial adaptations to nectar feeding among the strepsirrhines of Madagascar in order to provide such links. Many Malagasy strepsirrhines are considered effective cross-pollinators of the flowers they feed from, and nectar consumption represents as much as 75% of total feeding time. Previous studies identified skeletal correlates to nectar feeding in the crania of nonprimate mammals; from these, nine cranial measurements were chosen to be the focus of the present study. Results indicate thatCheirogaleus, Varecia, andEulemurmirror other nectar-feeding mammals in having elongated crania and/or muzzles. These strepsirrhines might be effective cross-pollinators, lending support to the coevolution hypothesis.
Synthesis and Characterization of Nanorods in Sucrose Ester Water-in-Oil Microemulsion
Authors: Huang N. M.
Published: October 2011

We report the synthesis of nanorods in a nonionic sugar-based water-in-oil (w/o) microemulsion system using food grade sucrose ester as biosurfactant. was formed by mixing indium (III) chloride and thioacetamide in the water core of the microemulsion system. The as-prepared yellowish was characterized by X-ray diffractometry (XRD), UV-visible absorption spectroscopy (UV-Vis), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). Formation of spherical or rod-like nanomaterials was dependent on reaction time. Rod-like , arranged in bundles, was formed only after 2 days of reaction time. Upon longer aging time, a mixture of rod-like and spherical was formed. A plausible formation mechanism of the nanorods in the sucrose ester microemulsion was postulated. The diameter of the nanorods was found to be very small, which is  nm with aspect ratio of 20 : 1 (length : diameter).