bluuebunny/crossref_metadata_2025 huggingface dataset:
Emotional reactivity and regulation in anxious and nonanxious youth: a cell‐phone ecological momentary assessment study
Authors: Tan Patricia Z. , Forbes Erika E. , Dahl Ronald E. , Ryan Neal D. , Siegle Greg J. , Ladouceur Cecile D. , Silk Jennifer S.
Published: December 2011

Background:  Reviews have highlighted anxious youths’ affective disturbances, specifically, elevated negative emotions and reliance on ineffective emotion regulation strategies. However, no study has examined anxious youth’s emotional reactivity and regulation in real‐world contexts.

Methods:  This study utilized an ecological momentary assessment approach to compare real‐world emotional experiences of 65 youth with generalized anxiety disorder, social anxiety disorder, or social phobia (ANX) and 65 age‐matched healthy controls (CON), ages 9–13 years.

Results:  Hierarchical linear models revealed that ANX reported higher levels of average past‐hour peak intensity of nervous, sad and upset emotions than CON youth but similar levels during momentary reports of current emotion. As expected, ANX youth reported more frequent physiological reactions in response to a negative event; however, there were no group differences in how frequently they used cognitive–behavioral strategies. Avoidance, distraction and problem solving were associated with the down‐regulation of all negative emotions except nervousness for both ANX and CON youth; however, group differences emerged for acceptance, rumination and physiological responding.

Conclusions:  In real‐world contexts, ANX youth do not report higher levels of momentary negative emotions but do report heightened negative emotions in response to challenging events. Moreover, ANX youth report no differences in how frequently they use adaptive regulatory strategies but are more likely to have physiological responses to challenging events. They are also less effective at using some strategies to down‐regulate negative emotion than CON youth.
Research Review: Structural language in autistic spectrum disorder – characteristics and causes
Authors: Boucher Jill
Published: December 2011

Background:  Structural language anomalies or impairments in autistic spectrum disorder (ASD) are theoretically and practically important, although underrecognised as such. This review aims to highlight the ubiquitousness of structural language anomalies and impairments in ASD, and to stimulate investigation of their immediate causes and implications for intervention.

Method:  Studies of structural language in ASD are reviewed (based on a search of the literature and selected as meeting defined inclusion criteria), and explanatory hypotheses are discussed.

Results:  Some individuals with ASD never acquire language. Amongst those who do, language abilities range from clinically normal (ALN) to various degrees of impairment (ALI). Developmental trajectories and individual profiles are diverse, and minority subgroups have been identified. Specifically: language is commonly but not always delayed and delayed early language is always characterised by impaired comprehension and odd utterances, and sometimes by deviant articulation and grammar. Nevertheless, by school age an ‘ASD‐typical’ language profile emerges from group studies, with articulation and syntax least affected, and comprehension, semantics and certain facets of morphology most affected. Thus, even individuals with ALN have poor comprehension relative to expressive language; also semantic‐processing anomalies and idiosyncratic word usage. It is argued that impaired socio‐emotional‐communicative relating, atypical sensory‐perceptual processing, and uneven memory/learning abilities may underlie shared language anomalies across the spectrum; and that varying combinations of low nonverbal intelligence, semantic memory impairment and comorbidities including specific language impairment (SLI), hearing impairment, and certain medical syndromes underlie ALI and variation in individual profiles.

Conclusions:  Structural language is universally affected in ASD, due to a complex of shared and unshared causal factors. There is an urgent need for more research especially into the characteristics and causes of clinically significant language impairments.
Intercultural Effectiveness, Authoritarianism, and Ethnic Prejudice
Authors: NESDALE DREW , DE VRIES ROBBÉ MIKE , VAN OUDENHOVEN JAN PIETER
Published: December 2011

This study examined the extent to which intercultural effectiveness dimensions (cultural empathy, open‐mindedness, social initiative, emotional stability, flexibility) and right‐wing authoritarianism (RWA) predicted the ethnic prejudice of 166 Australian respondents toward Indigenous Australians. Intercultural effectiveness was assessed on the Multicultural Personality Questionnaire, and RWA was assessed on the RWA scale, whereas ethnic prejudice was measured on the Modern Racism Scale. The results revealed that intercultural effectiveness (open‐mindedness, flexibility, cultural empathy) was inversely related to ethnic prejudice, with open‐mindedness being the main predictor. Intercultural effectiveness was also inversely related to RWA, the latter being directly related to ethnic prejudice. The implications of these findings for the potential role of intercultural effectiveness in combating ethnic prejudice are discussed.
Platelet‐derived growth factor receptor‐β‐positive telocytes in skeletal muscle interstitium
Authors: Suciu Laura C. , Popescu Bogdan O. , Kostin Sawa , Popescu Laurentiu M.
Published: December 2011

Telocytes (TCs) represent a new cell type recently described in mammalian skeletal muscle interstitium as well as in other organs. These have a specific morphology and phenotype, both in situ and in vitro. Telocytes are cells with long and slender cell prolongations, in contact with other interstitial cells, nerve fibres, blood capillaries and resident stem cells in niches. Our aim was to investigate the potential contribution of TCs to micro‐vascular networks by immunofluorescent labelling of specific angiogenic growth factors and receptors. We found that in human skeletal muscle TCs were constantly located around intermediate and small blood vessels and endomysial capillaries. Epi‐fluorescence and laser confocal microscopy showed that TCs express c‐kit, platelet‐derived growth factor receptor (PDGFR)‐β and VEGF, both in situ and in vitro. Telocytes were constantly located in the perivascular or pericapillary space, as confirmed by double staining of c‐kit/CD31, PDGFR‐β/CD31 and PDGFR‐β/α‐smooth muscle actin, respectively. Electron microscopy (EM) differentiated between pericytes and other cell types. Laminin labelling showed that TCs are not enclosed or surrounded by a basal lamina in contrast to mural cells. In conclusion, a) PDGFR‐β could be used as a marker for TCs and b) TCs are presumably a transitional population in the complex process of mural cell recruitment during angiogenesis and vascular remodelling.
Disturbance regime changes the trait distribution, phylogenetic structure and community assembly of tropical rain forests
Authors: Ding Yi , Zang Runguo , Letcher Susan G. , Liu Shirong , He Fangliang
Published: December 2011

A rapidly increasing effort to merge functional community ecology and phylogenetic biology has increased our understanding of community assembly. However, studies using both phylogenetic‐ and trait‐based methods have been mainly conducted in old‐growth forests, with fewer studies in human‐disturbed communities, which play an increasingly important role in providing ecosystem services as primary forests are degraded. We used data from 18 1‐ha plots in tropical old‐growth forests and secondary forests with different disturbance histories (logging and shifting cultivation) and vegetation types (tropical lowland and montane forests) on Hainan Island, southern China. The distributions of 11 functional traits were compared among these six forest types. We used a null model approach to assess the effects of disturbance regimes on variation in response and effect traits and community phylogenetic structure across different stem sizes (saplings, treelets, and adult trees) and spatial scales (10–50 m). We found significant differences in the distribution of functional traits in highly disturbed lowland sites versus other forest types. Many individuals in highly disturbed lowland sites were deciduous, spiny, with non‐fleshy fruits and seeds dispersed passively or by wind, and low SLA. The response traits of coexisting species were clustered in all sites except for highly disturbed lowland sites where evenness was evident. There were different distributions of effect traits for saplings and treelets among different forest types but adult trees showed stronger clustering of trait values with increasing spatial scale among all forest types. Phylogenetic clustering predominated across all size classes and spatial scales in the highly disturbed lowland sites, and evenness in other forest types. High disturbance can lead to abiotic filtering, generating a community dominated by closely related species with disturbance‐adapted traits, where biotic interactions play a relatively minor role. In lightly disturbed and old growth forests, multiple processes simultaneously drive the community assembly, but biotic processes dominate at the fine scale.
Negative Results: Why Do they Need to be Published?
Authors: Sandercock Peter
Published: December 2011

This short narrative review article defines ‘negative results’ and cites several ethical and scientific reasons why such studies should be made publicly available.
A Multicentre, Randomized, Double-Blinded, Placebo-Controlled Phase III Study to Investigate Extending the Time for Thrombolysis in Emergency Neurological Deficits (EXTEND)
Authors: Ma Henry , Parsons Mark W. , Christensen Soren , Campbell Bruce C. V. , Churilov Leonid , Connelly Alan , Yan Bernard , Bladin Chris , Phan Than , Barber Alan P. , Read Stephen , Hankey Graeme J. , Markus Romesh , Wijeratne Tissa , Grimley R. , Mahant N. , Kleinig Tim , Sturm John , Lee A. , Blacker D. , Gerraty Richard , Krause M. , Desmond P. M. , McBride S. J. , Carey Leanne , Howells David W. , Hsu C. Y. , Davis Stephen M. , Donnan Geoffrey A. ,   on behalf of the EXTEND investigators
Published: December 2011

Background and hypothesis

Thrombolytic therapy with tissue plasminogen activator is effective for acute ischaemic stroke within 4·5 h of onset. Patients who wake up with stroke are generally ineligible for stroke thrombolysis. We hypothesized that ischaemic stroke patients with significant penumbral mismatch on either magnetic resonance imaging or computer tomography at three- (or 4·5 depending on local guidelines) to nine-hours from stroke onset, or patients with wake-up stroke within nine-hours from midpoint of sleep duration, would have improved clinical outcomes when given tissue plasminogen activator compared to placebo.

Study design

EXtending the time for Thrombolysis in Emergency Neurological Deficits is an investigator-driven, Phase III, randomized, multicentre, double-blind, placebo-controlled study. Ischaemic stroke patients presenting after the three- or 4·5-h treatment window for tissue plasminogen activator and within nine-hours of stroke onset or with wake-up stroke within nine-hours from the midpoint of sleep duration, who fulfil clinical (National Institutes of Health Stroke Score ≥4–26 and prestroke modified Rankin Scale <2) will undergo magnetic resonance imaging or computer tomography. Patients who also meet imaging criteria (infarct core volume <70 ml, perfusion lesion : infarct core mismatch ratio >1·2, and absolute mismatch >10 ml) will be randomized to either tissue plasminogen activator or placebo.

Study outcome

The primary outcome measure will be modified Rankin Scale 0–1 at day 90. Clinical secondary outcomes include categorical shift in modified Rankin Scale at 90 days, reduction in the National Institutes of Health Stroke Score by 8 or more points or reaching 0–1 at day 90, recurrent stroke, or death. Imaging secondary outcomes will include symptomatic intracranial haemorrhage, reperfusion and or recanalization at 24 h and infarct growth at day 90.
‘Next‐base’ effect on PCR amplification
Authors: Ben‐Dov Eitan , Shapiro Orr H. , Kushmaro Ariel
Published: December 2011

The base adjacent to the 3′ end of universal PCR primers targeting the 16S rRNA gene is often variable and apparently biases the microbial community composition as represented by PCR‐based surveys. To test this hypothesis, four templates of 44 bases each and two complementary primers (21 bases) were designed to differ only in the bases adjacent to the primers, and their amplification efficiencies were evaluated using quantitative PCR. For extension temperatures of 72°C, 73°C and 74°C, improvement in initial amplification efficiency was observed for templates with guanine or cytosine at the position contiguous to the primers. However, no clear preference was observed when extension temperature was lowered to 70°C. Shortening the primers by one base, so that the variable position was located two base pairs downstream from the primer, attenuated but did not eliminate this bias. A conformational change of the quaternary polymerase – primer – template – dNTP complex upon commencing of polymerization is thought to be a rate‐limiting step. A possible explanation for the observed bias is the stabilization of this complex by the adjacent guanine or cytosine. Reducing PCR extension temperature to 70°C minimizes amplification biases caused by variable template‐contiguous bases to the 3′ end of universal PCR primers. Next‐base nucleotide composition should be taken in consideration in designing primers targeting 16S rRNA or other functional genes used in microbial ecology studies.
Convergence on Cattle: Political Ecology, Social Group Perceptions, and Socioeconomic Relationships in Acre, Brazil
Authors: Hoelle Jeffrey
Published: December 2011

Cattle raising is currently the leading cause of deforestation in Amazonia, and an increasingly appealing and profitable way for a growing number of smallholders to make a living in the western Amazon state of Acre, Brazil. The Acrean rubber tapper social movement contested the arrival of cattle ranchers in the 1970s and 1980s, but cattle raising has expanded among smallholder groups, including the rubber tappers, over the past 20 years. Building on the legacy of political–economic analyses of Amazonian cattle raising, this study argues for an expanded view of cattle raising by incorporating perspectives on the cultural constructions surrounding cattle and intergroup socioeconomic relationships. Data obtained from surveys and participant observation are used to examine the factors that have contributed to the expansion of cattle raising across three Acrean groups, each historically distinguished by their unique forms of livelihood and associated identities: forest‐extractivist rubber tappers, agricultural colonists, and large‐scale ranchers. It is argued that three factors have contributed to the growth of cattle ranching among these groups: political and economic shifts, which have made agricultural and extractive livelihoods less competitive with cattle raising; the spread of positive cultural views surrounding cattle raising; and the transition of intergroup relationships from conflict to cooperation in the cattle industry.
Increasing the Passive Scalar Mixing Quality of Jets in Crossflow With Fluidics Actuators
Authors: Lacarelle Arnaud , Paschereit Christian O.
Published: December 2011

Jets in crossflow are widely used in the industry for homogenization or cooling tasks. Recently, pulsating jets have been investigated as a mean to increase the scalar mixing efficiency of such configurations, whether for a single jet or for an array of jets. To avoid the disadvantages of mechanically actuated flows (costs, maintenance), a new injector based on a fluidics oscillator has been designed. Four injectors have been implemented in a generical jet in crossflow configuration and the mixing efficiency of the setup was compared with the one of the same setup equiped with standard non oscillating jets. With help of high-speed concentration measurement technique, the scalar mixing quality of both setups was measured at three positions downstream of the injection plane. In all the cases tested, the fluidics injectors present a better temporal homogenization, characterized by the Danckwerts unmixedness criterion, than the standard jets. For a defined mixing quality, a decrease of the mixing length by approximately 50% can be achieved with the fluidics injectors. Furthermore, the new injectors exhibit a mixing quality which is less sensitive to variations of the jet to crossflow momentum. The flapping motion of the fluidics injectors induces a wider azimuthal spreading of the fluidics jets immediately downstream of the injection location. This increases the macro- and micro-mixing phenomea which lead then to the high gains in mixing quality. It is thus demonstrated that fluidics oscillators present a strong potential to improve the passive scalar homogenization of jet in crossflow configurations.
Effect of Severe Prior Deformation on Electrical-Assisted Compression of Copper Specimens
Authors: Siopis Michael S. , Kinsey Brad L. , Kota Nithyanand , Ozdoganlar O. Burak
Published: December 2011

In electrical-assisted forming (EAF), current is passed through the material during the deformation process, which results in a decrease in the required flow stress for the material. While resistive heating occurs, the flow stress reductions are beyond what can be explained by temperature effects alone. Hypotheses for this effect relate to the current affecting dislocation generation and aiding dislocation motion through the lattice structure. If the latter was the case, then materials with higher dislocation densities from severe deformation should have more pronounced benefits from EAF. In this research, Equal channel angular extrusion (ECAE) was used to induce severe plastic deformation into the material. Subsequent EAF compression experiments with the ECAE specimens and as-received material with comparable grain sizes were conducted. As expected, the EAF process reduced the flow stress value substantially more, e.g., 224 MPa versus 115 MPa at a strain of 0.8 for the ECAE specimens compared to the as-received specimens, respectively. These flow stress reductions were from a case with no current applied to a case where an initial current density of 250 A/mm2 was applied. EAF may particularly be beneficial at the microscale to address size effects as the current required to achieve an elevated current density is more viable.
Characterization of Tensile and Compressive Behavior of Microscale Sheet Metals Using a Transparent Microwedge Device
Authors: Magargee James , Cao Jian , Zhou Rui , McHugh Morgan , Brink Damon , Morestin Fabrice
Published: December 2011

The cyclic and compressive mechanical behavior of ultrathin sheet metals was experimentally investigated. A novel transparent wedge device was designed and fabricated to prevent the buckling of thin sheets under compressive loads, while also allowing full field strain measurements of the specimen using digital imaging methods. Thin brass and stainless steel sheet metal specimens with thicknesses on the order of 10–100 μm were tested using the microwedge device. Experimental results show that the device can be used to delay the onset of early buckling modes of a thin sheet under compression, which is critical in examining the compressive and cyclic mechanical behavior of sheet metals.
Structural and luminescent properties of bulk InAsSb
Authors: Sarney W. L. , Svensson S. P. , Hier H. , Kipshidze G. , Donetsky D. , Wang D. , Shterengas L. , Belenky G.
Published: December 2011

The strong bandgap bowing in the InAsxSb1−x alloy system allows it to potentially be used for infrared photodetection in the middle and long wavelength range. The authors have used compositionally graded metamorphic buffer layers to accommodate the misfit strain between InAsxSb1−x alloys and GaSb and InSb substrates in order to reach the long wave infrared range. In this work, we present the characterization of metamorphically grown InAsxSb1−x films that demonstrate strong photoluminescence in the spectral range from 5 to 9 μm.
Dynamics of Dengue Disease Severity Determined by the Interplay Between Viral Genetics and Serotype-Specific Immunity
Authors: OhAinle Molly , Balmaseda Angel , Macalalad Alexander R. , Tellez Yolanda , Zody Michael C. , Saborío Saira , Nuñez Andrea , Lennon Niall J. , Birren Bruce W. , Gordon Aubree , Henn Matthew R. , Harris Eva
Published: December 2011

The complex interactions between serotype-specific immunity and viral genetics drive dengue disease outcomes in endemic populations.
Mapping the Road Forward in Alzheimer’s Disease
Authors: Holtzman David M. , Goate Alison , Kelly Jeffrey , Sperling Reisa
Published: December 2011

A better understanding of genetics, protein aggregation, and neurobiology combined with improved clinical trial design is needed to combat Alzheimer’s disease.
Far from Home
Authors: Boxer Rebecca S.
Published: December 2011

Circulating bone cell precursors might promote ossification in diseased aortic valves.
Acetylcholine: Working on Working Memory
Authors: Mashour George A.
Published: December 2011

Depletion of cholinergic neurons in the prefrontal cortex causes loss of a specific memory function in rhesus monkeys.
Real-Time PCR Analysis of the Intestinal Microbiotas in Peritoneal Dialysis Patients
Authors: Wang I-Kuan , Lai Hsueh-Chou , Yu Cheng-Ju , Liang Chih-Chia , Chang Chiz-Tzung , Kuo Huey-Liang , Yang Ya-Fei , Lin Chung-Chih , Lin Hsin-Hung , Liu Yao-Lung , Chang Yi-Chih , Wu Yi-Ying , Chen Chu-Huang , Li Chi-Yuan , Chuang Feng-Rong , Huang Chiu-Ching , Lin Chih-Hsueh , Lin Hung-Chih
Published: December 2011

Bifidobacterium
and
Lactobacillus
can beneficially affect the host by producing acetic acid and lactic acid, which lower pH and thereby inhibit the growth of pathogens or allow the probiotic bacteria to compete with pathogens for epithelial adhesion sites and nutrients. The transmural migration of enteric organisms into the peritoneal cavity can cause peritonitis in peritoneal dialysis (PD) patients. We hypothesized that the composition of the intestinal microbiota with regard to
Lactobacillus
species and
Bifidobacterium
species differed between PD patients and healthy controls. The aim of the study was to investigate these differences by real-time PCR analysis of fecal samples. From 1 August 2009 to 31 March 2010, a total of 29 nondiabetic PD patients and 41 healthy controls from China Medical University Hospital were recruited after giving their informed consent. Fecal samples were collected from the PD patients and their age-matched counterparts in the morning using a standardized procedure. DNA extracted from these samples was analyzed by real-time PCR. All bifidobacteria,
Bifidobacterium catenulatum
,
B. longum
,
B. bifidum
,
Lactobacillus plantarum
,
L. paracasei
, and
Klebsiella pneumoniae
were less frequently detected in the patient samples. Dysbiosis (microbial imbalance) may impair intestinal barrier function and increase host vulnerability to pathogen invasion. Further studies are necessary to confirm our findings before clinical trials with probiotic supplementation in PD patients.
Highly Efficient Staphylococcus carnosus Mutant Selection System Based on Suicidal Bacteriocin Activation
Authors: Krismer Bernhard , Nega Mulugeta , Thumm Günther , Götz Fritz , Peschel Andreas
Published: December 2011

Strains from various staphylococcal species produce bacteriocin peptides, which are thought to play important roles in bacterial competition and offer interesting biotechnological avenues. Many bacteriocins are secreted as inactive prepeptides with subsequent activation by specific proteolytic cleavage. By deletion of the protease gene
gdmP
in
Staphylococcus gallinarum
Tü3928, which produces the highly active lanthionine-containing bacteriocin gallidermin (lantibiotic), a strain was created producing inactive pregallidermin. On this basis, a new suicidal mutant selection system in the food-grade bacterium
Staphylococcus carnosus
was developed. Whereas pregallidermin was inactive against
S. carnosus
, it exerted potent bactericidal activity toward GdmP-secreting
S. carnosus
strains. To take advantage of this effect,
gdmP
was cloned in plasmid vectors used for random transposon mutagenesis or targeted allelic replacement of chromosomal genes. Both mutagenesis strategies rely on rare recombination events, and it has remained difficult and laborious to identify mutants among a vast majority of bacterial clones that still contain the delivery vectors. The
gdmP
-expressing plasmids pGS1 and pGS2 enabled very fast, easy, and reliable identification of transposon and gene replacement mutants, respectively. Mutant selection in the presence of pregallidermin caused suicidal inactivation of all clones that had retained the plasmids and allowed growth of only plasmid-cured mutants. Efficiency of mutant identification was several magnitudes higher than standard screening for the absence of plasmid-encoded antibiotic resistance markers and reached 100% specificity. Thus, the new pregallidermin-based mutant selection system represents a substantial improvement of staphylococcal mutagenesis methodology.
Evolutionary Silence of the Acid Chaperone Protein HdeB in Enterohemorrhagic Escherichia coli O157:H7
Authors: Carter Michelle Q. , Louie Jacqueline W. , Fagerquist Clifton K. , Sultan Omar , Miller William G. , Mandrell Robert E.
Published: December 2011

The periplasmic chaperones HdeA and HdeB are known to be important for cell survival at low pH (pH < 3) in
Escherichia coli
and
Shigella
spp. Here we investigated the roles of HdeA and HdeB in the survival of various enterohemorrhagic
E. coli
(EHEC) following exposure to pH 2.0. Similar to K-12 strains, the acid protections conferred by HdeA and HdeB in EHEC O145 were significant: loss of HdeA and HdeB led to over 100- to 1,000-fold reductions in acid survival, depending on the growth condition of prechallenge cells. However, this protection was much less in
E. coli
O157:H7 strains. Deletion of
hdeB
did not affect the acid survival of cells, and deletion of
hdeA
led to less than a 5-fold decrease in survival. Sequence analysis of the
hdeAB
operon revealed a point mutation at the putative start codon of the
hdeB
gene in all 26
E. coli
O157:H7 strains analyzed, which shifted the ATG start codon to ATA. This mutation correlated with the lack of HdeB in
E. coli
O157:H7; however, the plasmid-borne O157-
hdeB
was able to restore partially the acid resistance in an
E. coli
O145Δ
hdeAB
mutant, suggesting the potential function of O157-HdeB as an acid chaperone. We conclude that
E. coli
O157:H7 strains have evolved acid survival strategies independent of the HdeA/B chaperones and are more acid resistant than nonpathogenic K-12 for cells grown under nonfavorable culturing conditions such as in Luria-Bertani no-salt broth at 28°C. These results suggest a divergent evolution of acid resistance mechanisms within
E. coli
.
How Posttranslational Modification of Nitrogenase Is Circumvented in Rhodopseudomonas palustris Strains That Produce Hydrogen Gas Constitutively
Authors: Heiniger Erin K. , Oda Yasuhiro , Samanta Sudip K. , Harwood Caroline S.
Published: December 2011

Nitrogenase catalyzes the conversion of dinitrogen gas (N2) and protons to ammonia and hydrogen gas (H2). This is a catalytically difficult reaction that requires large amounts of ATP and reducing power. Thus, nitrogenase is not normally expressed or active in bacteria grown with a readily utilized nitrogen source like ammonium.nifA*mutants of the purple nonsulfur phototrophic bacteriumRhodopseudomonas palustrishave been described that express nitrogenase genes constitutively and produce H2when grown with ammonium as a nitrogen source. This raised the regulatory paradox of why these mutants are apparently resistant to a known posttranslational modification system that should switch off the activity of nitrogenase. Microarray, mutation analysis, and gene expression studies showed that posttranslational regulation of nitrogenase activity inR. palustrisdepends on two proteins: DraT2, an ADP-ribosyltransferase, and GlnK2, an NtrC-regulated PIIprotein. GlnK2 was not well expressed in ammonium-grown NifA* cells and thus not available to activate the DraT2 nitrogenase modification enzyme. In addition, the NifA* strain had elevated nitrogenase activity due to overexpression of thenifgenes, and this increased amount of expression overwhelmed a basal level of activity of DraT2 in ammonium-grown cells. Thus, insufficient levels of both GlnK2 and DraT2 allow H2production by annifA*mutant grown with ammonium. Inactivation of the nitrogenase posttranslational modification system by mutation ofdraT2resulted in increased H2production by ammonium-grown NifA* cells.
MADS Box Transcription Factor Mbx2/Pvg4 Regulates Invasive Growth and Flocculation by Inducing
gsf2
+
Expression in Fission Yeast
Authors: Matsuzawa Tomohiko , Yoritsune Ken-ichi , Takegawa Kaoru
Published: December 2011

The fission yeast
Schizosaccharomyces pombe
exhibits invasive growth and nonsexual flocculation in response to nitrogen limitation. Gsf2, a flocculin of fission yeast, is required not only for nonsexual flocculation but also for invasive growth through the recognition of galactose residues on cell surface glycoconjugates. We found that pyruvylation negatively regulates nonsexual flocculation by capping the galactose residues of
N
-linked galactomannan. We investigated whether pyruvylation also regulates invasive growth. The
pvg4
+
gene originally was isolated as a multicopy suppressor of a
pvg4
mutant defective in the pyruvylation of
N
-linked oligosaccharides. However, we did not detect a defect in cell surface pyruvylation in the
pvg4
/
mbx2
deletion mutant, as assessed by alcian blue staining and a Q-Sepharose binding assay. Instead, the deletion prevented invasive growth under conditions of low nitrogen and high glucose, and it reduced the adhesion and flocculation of otherwise flocculent mutants by reducing
gsf2
+
expression.
mbx2
+
-overexpressing strains exhibited nonsexual and calcium-dependent aggregation, which was inhibited in the presence of galactose but mediated by the induction of
gsf2
+
. These findings indicate that Mbx2 mediates invasive growth and flocculation via the transcriptional activation of
gsf2
+
in fission yeast. In addition, we found that fission yeast Mbx2 induces the nonsexual flocculation of budding yeast by the activation of
FLO1
.
Membrane Topology of the Bacillus anthracis GerH Germinant Receptor Proteins
Authors: Wilson Mary J. , Carlson Paul E. , Janes Brian K. , Hanna Philip C.
Published: December 2011

Bacillus anthracis
spores are the etiologic agent of anthrax. Nutrient germinant receptors (nGRs) packaged within the inner membrane of the spore sense the presence of specific stimuli in the environment and trigger the process of germination, quickly returning the bacterium to the metabolically active, vegetative bacillus. This ability to sense the host environment and initiate germination is a required step in the infectious cycle. The nGRs are comprised of three subunits: the A-, B-, and C-type proteins. To date there are limited structural data for the A- and B-type nGR subunits. Here the transmembrane topologies of the
B. anthracis
GerH
A
, GerH
B
, and GerH
C
proteins are presented. C-terminal green fluorescent protein (GFP) fusions to various lengths of the GerH proteins were overexpressed in vegetative bacteria, and the subcellular locations of these GFP fusion sites were analyzed by flow cytometry and protease sensitivity. GFP fusion to full-length GerH
C
confirmed that the C terminus of this protein is extracellular, as predicted. GerH
A
and GerH
B
were both predicted to be integral membrane proteins by topology modeling. Analysis of C-terminal GFP fusions to full-length GerH
B
and nine truncated GerH
B
proteins supports either an 8- or 10-transmembrane-domain topology. For GerH
A
, C-terminal GFP fusions to full-length GerH
A
and six truncated GerH
A
proteins were consistent with a four-transmembrane-domain topology. Understanding the membrane topology of these proteins is an important step in determining potential ligand binding and protein-protein interaction domains, as well as providing new information for interpreting previous genetic work.
Herpesvirus Replication Compartments Originate with Single Incoming Viral Genomes
Authors: Kobiler O. , Brodersen P. , Taylor M. P. , Ludmir E. B. , Enquist L. W.
Published: December 2011

Previously we described a method to estimate the average number of virus genomes expressed in an infected cell. By analyzing the color spectrum of cells infected with a mixture of isogenic pseudorabies virus (PRV) recombinants expressing three fluorophores, we estimated that fewer than seven incoming genomes are expressed, replicated, and packaged into progeny per cell. In this report, we expand this work and describe experiments demonstrating the generality of the method, as well as providing more insight into herpesvirus replication. We used three isogenic PRV recombinants, each expressing a fluorescently tagged VP26 fusion protein (VP26 is a capsid protein) under the viral VP26 late promoter. We calculated a similar finite limit on the number of expressed viral genomes, indicating that this method is independent of the promoter used to transcribe the fluorophore genes, the time of expression of the fluorophore (early versus late), and the insertion site of the fluorophore gene in the PRV genome (UL versus US). Importantly, these VP26 fusion proteins are distributed equally in punctate virion assembly structures in each nucleus, which improves the signal-to-noise ratio when determining the color spectrum of each cell. To understand how the small number of genomes are distributed among the replication compartments, we used a two-color fluorescent
in situ
hybridization assay. Most viral replication compartments in the nucleus occupy unique nuclear territories, implying that they arose from single genomes. Our experiments suggest a correlation between the small number of expressed viral genomes and the limited number of replication compartments.

IMPORTANCE
Herpesviruses use nuclear factors and architecture to replicate their DNA genomes in the host nuclei. Viral replication compartments are distinct nuclear foci that appear during productive infection. We have recently developed a method that uses three viral recombinants (each expressing a different fluorescent protein) to quantify the number of incoming viral genomes that are expressed and replicated in each cell. We found that fewer than seven herpesvirus genomes can be expressed and replicated. Here we have expanded and improved upon our method and demonstrated that the phenomenon of limited genome expression is independent of the recombinants used. We correlated the small number of genomes expressed to the limited number of replication compartments by demonstrating that most replication compartments originate with a single genome. The distinction among replication compartments is maintained even when most of the nucleus is filled with viral DNA, implying that nuclear architecture constrains the compartments.
Dissemination of the Klebsiella pneumoniae Carbapenemase in the Health Care Settings: Tracking the Trails of an Elusive Offender
Authors: Adler Amos , Carmeli Yehuda
Published: December 2011

Transmission of antibiotic resistance genes may be mediated by a variety of molecular mechanisms, from mobility of small genetic elements to clonal spread. Since 1997, the carbapenem-hydrolyzing enzyme
Klebsiella pneumoniae
carbapenemase (KPC) has spread in the United States and across the world, mainly via a single
K. pneumoniae
clone, sequence type 258. By tracking the trail of dissemination of the
bla
KPC
gene inside their institution, Mathers et al. (mBio 2:e00204–11, 2011) have shown evidence of the ability of this gene to spread by several modes, including plasmid transfer and clonal spread. The ever-evolving modes of transmission of resistance genes challenge our ability to detect, track, and eventually control the spread of what has become a major threat to hospitalized patients worldwide.
Intravenous paracetamol versus morphine for renal colic in the emergency department: a randomised double-blind controlled trial
Authors: Serinken Mustafa , Eken Cenker , Turkcuer Ibrahim , Elicabuk Hayri , Uyanik Emrah , Schultz Carl H
Published: December 2011

Objective

To determine the analgesic efficacy and safety of intravenous single-dose paracetamol versus morphine in patients presenting to the emergency department with renal colic.

Methods

A randomised double-blind study was performed to compare the efficacy of intravenous paracetamol (1 g) and 0.1 mg/kg morphine in patients with renal colic. The efficacy of the study drugs was measured by a visual analogue scale and a verbal rating scale at baseline and after 15 and 30 min. The adverse effects and need for rescue medication (1 μg/kg intravenous fentanyl) were also recorded at the end of the study.

Results

133 patients were eligible for enrolment in the study, with 73 patients included in the final analysis (38 in the paracetamol group and 35 in the morphine group). The mean±SD age of the subjects was 30.2±8.6 years and 51 (70%) were men. The mean reduction in scores at 30 min after study drug administration was 63.7 mm (95% CI 57 to 71) for paracetamol and 56.6 mm (95% CI 48 to 65) for morphine. The difference between pain reduction scores for the two groups at 30 min was 7.1 mm (95% CI −18 to 4), demonstrating no statistical or clinical significance. Two adverse events (5.3%) were recorded in the paracetamol group and five (14.3%) in the morphine group (difference 9%, 95% CI −7% to 26%).

Conclusion

Intravenous paracetamol is effective in treating patients presenting with renal colic to the emergency department.

Clinical trials registration no

ClinicalTrials.gov ID numberNCT01318187.
The need for a usable assessment tool to analyse the efficacy of emergency care systems in developing countries: proposal to use the TEWS methodology
Authors: Sun Jared H , Twomey Michele , Tran Jeffrey , Wallis Lee A
Published: December 2011

Background

Ninety percent of emergency incidents occur in developing countries, and this is only expected to get worse as these nations develop. As a result, governments in developing countries are establishing emergency care systems. However, there is currently no widely-usable, objective method to monitor or research the rapid growth of emergency care in the developing world.

Methods

Analysis of current quantitative methods to assess emergency care in developing countries, and the proposal of a more appropriate method.

Results

Currently accepted methods to quantitatively assess the efficacy of emergency care systems cannot be performed in most developing countries due to weak record-keeping infrastructure and the inappropriateness of applying Western derived coefficients to developing country conditions. As a result, although emergency care in the developing world is rapidly growing, researchers and clinicians are unable to objectively measure its progress or determine which policies work best in their respective countries. We propose the TEWS methodology, a simple analytical tool that can be handled by low-resource, developing countries.

Conclusions

By relying on the most basic universal parameters, simplest calculations and straightforward protocol, the TEWS methodology allows for widespread analysis of emergency care in the developing world. This could become essential in the establishment and growth of new emergency care systems worldwide.
Detection of elephant endotheliotropic herpesvirus type 1 in asymptomatic elephants using TaqMan real‐time PCR
Authors: Hardman K. , Dastjerdi A. , Gurrala R. , Routh A. , Banks M. , Steinbach F. , Bouts T.
Published: December 2011

This study assessed the feasibility of identifying asymptomatic viral shedders using a novel TaqMan real‐time PCR on trunk washes and swabs from the conjunctiva, palate and vulva of elephants. Six elephants from a UK collection were sampled weekly over a period of 11 weeks for this study. The herd prevalence of elephant endotheliotropic herpesvirus‐1 (EEHV‐1) was 100 per cent by PCR. The virus DNA was detected in all the sampling sites; however, the prevalence of virus DNA in the conjunctiva swabs was higher. In addition, Asian elephants from two continental European collections were sampled once and one animal tested positive on a trunk wash. The virus from this animal was phylogenetically typed as EEHV‐1A based on 231 nucleotides of the terminase gene.
Prevalence of Coxiella burnetii infections in aborted fetuses and stillborn calves
Authors: Muskens J. , Wouda W. , von Bannisseht‐Wijsmuller T. , van Maanen C.
Published: December 2011

Coxiella burnetii infections are mostly subclinical in cattle, but can occasionally be associated with abortion. In the present study, 100 aborted fetuses or stillborn calves that were submitted for postmortem examination between September 2007 and March 2008 were examined for infection with C burnetii. Samples of both pooled fetal tissues and placental cotyledon were tested using a real‐time PCR assay. In addition, the sections of placental cotyledon were examined using immunohistochemistry (IHC). The IHC of four placentas was positive. The PCR results of the IHC‐positive placentas were high positive (HP); the PCR results of the organs of these four fetuses and calves varied from low positive (LP) to HP. The four IHC‐positive fetuses had a gestation length of seven to nine months. All four placentas had histological signs of inflammation, but only one of four placentas had gross pathological signs of inflammation possibly due to a concomitant infection with Bacillus licheniformis. Five other IHC‐negative placentas had (high) positive PCR results; the PCR results of the organs of these fetuses were LP or negative. The present study indicates that C burnetii infections are detected in a limited percentage of aborted fetuses and stillborn calves by IHC. To assess the importance of placentas with PCR‐positive and IHC‐negative test results, more research is needed.
False rings in the white pine (Pinus strobus) of the Outaouais Hills, Québec (Canada), as indicators of water stress
Authors: Marchand Neil , Filion Louise
Published: December 2011

False rings are intra-annual bands of wood darker than the adjacent wood. They have been reported for several species of Pinus, although not previously for white pine (Pinus strobus L.). In southwestern Quebec, false rings were found to be very common among white pine, an indication that the species is sensitive to water stress in this region. False rings were analyzed on 110 trees from 12 mature stands. A false ring database was built, and false ring chronologies were established and analyzed for two groups of sites (rocky outcrops and shallow soils). The years 1955, 1959, and 1988 were those with the highest occurrence of false rings (62% to 90% of all stems). Factors predisposing false ring formation include the cambial age of stems bearing false rings and drainage conditions (dry rocky outcrop sites). Triggering factors were climatic events occurring during the four-month growing season. Years with low precipitation correlate with years featuring a higher occurrence of false rings. High summer temperatures may also be involved, as they explain the distribution of false rings in all frequency classes. In areas where they form, false rings in white pine can be used as diagnostic rings and as indicators of water stress.
Needle browning and death in Pinus pumila in the alpine region of central Japan were not related to mechanical damage of cuticle and cuticle thickness
Authors: Nakamoto Aoi , Ikeda Takefumi , Maruta Emiko
Published: December 2011

The browning and death of needles of evergreen conifers in alpine regions occur mainly in early spring at the point where the shoot protrudes from the snowpack. They are thought to be caused by excessive transpiration due to mechanical damage to the cuticle or to a thinner cuticle. However, there are a few studies that do not necessarily agree with this idea. We assessed needle browning and death in Pinus pumila (Pallas) Regel. in the alpine region of Japan in relation to mechanical damage to the cuticle, cuticular resistance, and cuticle thickness. Mechanical damage was not observed on needle cuticles of Pinus pumila browning in a natural environment. The color of needles with artificially abraded cuticles changed from green to brown in the abraded part. However, the brown color at the abraded part differed from the brown of a browning needle in its natural environment. There was no correlation between cuticular resistance and cuticle thickness. Needle browning and death in P. pumila were not related to mechanical damage of the cuticle or to cuticle thickness but might be due to changes in the quality and structure of the cuticle and other stresses.
Effects of cultural intensity and planting density on stand-level aboveground biomass production and allocation for 12-year-old loblolly pine plantations in the Upper Coastal Plain and Piedmont of the southeastern United States
Authors: Zhao Dehai , Kane Michael , Borders Bruce , Subedi Santosh , Akers Madison
Published: December 2011

To strengthen financial returns and sustainably manage pine plantations for a mixture of traditional merchantable forest products and biomass for energy, we may need to modify and optimize loblolly pine ( Pinus taeda L.) plantation management regimes. There is limited information on stand-level biomass production and partitioning, which is critical to evaluate alternative culture regimes including cultural intensity and planting density. In the present study, effects of cultural intensity and planting density on biomass accumulation and partitioning in loblolly pine plantations at age 12 were evaluated with destructive biomass sampling data from plots of a unique culture/density study. More intensive culture increased stand-level stem, bark, and branch biomass and aboveground biomass but did not affect foliage biomass. In general, culture intensity did not affect stand-level aboveground biomass partitioning. Planting density significantly affected stand-level aboveground biomass accumulation and partitioning; however, this effect was no longer significant among densities above 2224 trees·ha–1. More intensive culture or lower planting density resulted in less foliage per unit of live-branch biomass. Partitioning to stems relative to branches increased with increasing planting density. Both cultural intensity and planting density had no significant effects on leaf area index and stand-level specific gravity. Planting density significantly affected the foliage density. There were no significant interactions of planting density and cultural intensity.
SUBSPACES OF A PARA-QUATERNIONIC HERMITIAN VECTOR SPACE
Authors: VACCARO MASSIMO
Published: December 2011

Let [Formula: see text] be a para-quaternionic Hermitian structure on the real vector space V. By referring to the tensorial presentation [Formula: see text], we give an explicit description, from an affine and metric point of view, of main classes of subspaces of V which are invariantly defined with respect to the structure group of [Formula: see text] and [Formula: see text] respectively.
MECHANICAL SYSTEMS ON GENERALIZED-QUATERNIONIC KÄHLER MANIFOLDS
Authors: TEKKOYUN MEHMET , YAYLI YUSUF
Published: December 2011

In this paper, we introduce generalized-quaternionic Kähler analogue of Lagrangian and Hamiltonian mechanical systems. Finally, the geometrical-physical results related to generalized-quaternionic Kähler mechanical systems are also given.
Radio-Frequency Electron Accelerators for Industrial Applications
Authors: Cleland Marshall R.
Published: December 2011

Two types of radio-frequency electron accelerators are described in this article. They operate in the frequency range of 100–200 MHz and are energized with triode or tetrode tubes instead of klystrons. They can provide more powerful electron beams than typical microwave linear accelerators.