bluuebunny/crossref_metadata_2025 huggingface dataset:
Intermittent collective dynamics emerge from conflicting imperatives in sheep herds
Authors: Ginelli Francesco , Peruani Fernando , Pillot Marie-Helène , Chaté Hugues , Theraulaz Guy , Bon Richard
Published: September 2015

Significance

We report and analyze quantitative field observations of large groups of Merino sheep. While grazing, these sheep must balance two competing needs: (i) the maximization of individual foraging space and (ii) the protection from predators offered by a large dense group. We show that they resolve this conflict by alternating slow foraging phases—during which the group spreads out—with fast packing events triggered by an individual-level behavioral shift. This leads to an intermittent collective dynamics with large density oscillations triggered by packing events on all accessible scales: a quasi-critical state. All our findings are well accounted for by an explicit model with individual behavioral shifts and strong allelomimetic properties.
Endothelial miR-17∼92 cluster negatively regulates arteriogenesis via miRNA-19 repression of WNT signaling
Authors: Landskroner-Eiger Shira , Qiu Cong , Perrotta Paola , Siragusa Mauro , Lee Monica Y. , Ulrich Victoria , Luciano Amelia K. , Zhuang Zhen W. , Corti Federico , Simons Michael , Montgomery Rusty L. , Wu Dianqing , Yu Jun , Sessa William C.
Published: September 2015

Significance

MicroRNAs can repress target genes to regulate cellular function in vivo. The miR-17∼92 cluster is critical for cell cycle control, survival signaling, and angiogenesis, but the individual components of the cluster and their endogenous roles in vivo are less well understood. Here we show that the loss of endothelial-derived miR-17∼92 increases basal cardiac and limb arteriogenesis and improves ischemia-induced changes in blood flow. One component of the cluster, miR-19, directly targets FZD4 and LRP6, thereby regulating WNT signaling in vitro and in vivo, and antagonism of miR-19 up-regulates WNT signaling and improves defective blood flow recovery.
Global biogeography of human infectious diseases
Authors: Murray Kris A. , Preston Nicholas , Allen Toph , Zambrana-Torrelio Carlos , Hosseini Parviez R. , Daszak Peter
Published: September 2015

Significance

Understanding the distributions of infectious diseases is a central public and global health objective. We show that human infectious diseases exhibit striking biogeographic grouping patterns at a global scale, reminiscent of “Wallacean” zoogeographic patterns. This result is surprising, given the global distribution and unprecedented connectivity of humans as hosts and the homogenizing forces of globalization; despite these factors, infectious disease assemblages remain fundamentally constrained in their distributions by ecological barriers to dispersal or establishment. Biogeographic processes thus appear to provide an overarching context in which other factors promoting infectious disease emergence and spread are set. We use outbreaks of Ebola virus to illustrate how such patterns could be leveraged to provide a “head start” or added focus for risk management activities.
Contractility of single cardiomyocytes differentiated from pluripotent stem cells depends on physiological shape and substrate stiffness
Authors: Ribeiro Alexandre J. S. , Ang Yen-Sin , Fu Ji-Dong , Rivas Renee N. , Mohamed Tamer M. A. , Higgs Gadryn C. , Srivastava Deepak , Pruitt Beth L.
Published: September 2015

Significance

Human cardiomyocytes differentiated from pluripotent stem cells (hPSC-CMs) have potential as in vitro models of cardiac health and disease but differ from mature cardiomyocytes. In single live engineered hPSC-CMs with physiological shapes, we assayed the mechanical output and activity of sarcomeres and myofibrils in a nondestructive, noninvasive manner. Substrates with physiological stiffness improved contractile activity of patterned hPSC-CMs, as well as calcium flow, mitochondrial organization, electrophysiology, and transverse-tubule formation. The mechanical output and activity of sarcomeres and myofibrils varied as a function of mechanical cues and disrupted cell tension. This study establishes a high-throughput platform for modeling single-cell cardiac contractile activity and yields insight into environmental factors that drive maturation and sarcomere function in hPSC-CMs.
Glacial reduction and millennial-scale variations in Drake Passage throughflow
Authors: Lamy Frank , Arz Helge W. , Kilian Rolf , Lange Carina B. , Lembke-Jene Lester , Wengler Marc , Kaiser Jérôme , Baeza-Urrea Oscar , Hall Ian R. , Harada Naomi , Tiedemann Ralf
Published: September 2015

Significance

The Drake Passage (DP) represents the most important oceanic gateway along the pathway of the world’s largest current: the Antarctic Circumpolar Current (ACC). Resolving changes in the flow of circumpolar water masses through the DP is crucial for advancing our understanding of the Southern Ocean’s role in affecting ocean and climate change on a global scale. We reconstruct current intensity from marine sediment records around the southern tip of South America with unprecedented millennial-scale resolution covering the past ∼65,000 y. For the last glacial period, we infer intervals of strong weakening of the ACC entering the DP, implying an enhanced export of northern ACC surface and intermediate waters into the South Pacific Gyre and reduced Pacific–Atlantic exchange through the cold water route.
Chemical, experimental, and morphological evidence for diagenetically altered melanin in exceptionally preserved fossils
Authors: Colleary Caitlin , Dolocan Andrei , Gardner James , Singh Suresh , Wuttke Michael , Rabenstein Renate , Habersetzer Jörg , Schaal Stephan , Feseha Mulugeta , Clemens Matthew , Jacobs Bonnie F. , Currano Ellen D. , Jacobs Louis L. , Sylvestersen Rene Lyng , Gabbott Sarah E. , Vinther Jakob
Published: September 2015

Significance

Melanin is a widespread pigment that provides black to reddish brown hues to organisms. Recent evidence has shown that melanin is retained in exceptionally preserved fossils, including feathered dinosaurs, allowing the reconstruction of ancient color patterns. However, little is known about the chemical preservation of melanin or its distribution in the fossil record. Here, we show that melanin is preserved in a number of soft-bodied fossils, but its burial under high pressure and temperature for millions of years alters its original chemistry. The widespread occurrence of melanin substantiates the applicability of reconstructing aspects of original color patterns and allows us to dismiss the alternative suggestion that these structures are microbial in origin.
NhaA antiporter functions using 10 helices, and an additional 2 contribute to assembly/stability
Authors: Padan Etana , Danieli Tsafi , Keren Yael , Alkoby Dudu , Masrati Gal , Haliloglu Turkan , Ben-Tal Nir , Rimon Abraham
Published: September 2015

Significance

The principal Na
+
/H
+
antiporter of
Escherichia coli
(Ec-NhaA) is the best-characterized of the pH-regulated Na
+
/H
+
exchangers that control cellular Na
+
and H
+
homeostasis, and the human homologues are potentially important drug targets. Identification of the essential components of NhaA is vital to understanding the function of the protein and has implications for evolution and protein design. Ec-NhaA has 12 helices, 2 of which (VI and VII) are absent from the growing number of secondary transporters that share the unique Ec-NhaA structural fold. Mutants deleted of helices VI and VII, which form an α-hairpin at the dimer interface, are defective in the assembly/stability of the Ec-NhaA dimer but retain significant transport activity, as well as regulatory properties.
Mesoscopic quantum emitters from deterministic aggregates of conjugated polymers
Authors: Stangl Thomas , Wilhelm Philipp , Remmerssen Klaas , Höger Sigurd , Vogelsang Jan , Lupton John M.
Published: September 2015

Significance

Bright and stable single-photon sources, based on molecular objects, have contributed to exploring the foundations of quantum mechanics and measurement theory. Because the photon emission rate scales with molecular size, the most direct approach to increasing brightness is to enlarge the molecular object itself. But how big can it become while still retaining molecular characteristics of a deterministic photon source? We tackle this question by growing defined aggregates out of single chains of a conjugated polymer. Multichain aggregates show discrete single-photon emission, even when the individual chains display multiphoton emission. Single-aggregate spectroscopy reveals how coherent and incoherent excitonic intermolecular coupling mechanisms, known from the bulk, evolve with aggregate size.
Increased threat of tropical cyclones and coastal flooding to New York City during the anthropogenic era
Authors: Reed Andra J. , Mann Michael E. , Emanuel Kerry A. , Lin Ning , Horton Benjamin P. , Kemp Andrew C. , Donnelly Jeffrey P.
Published: September 2015

Significance

We combine proxy sea level records, downscaled tropical cyclone data sets, and storm surge models to investigate the impacts of rising sea levels and tropical cyclones on coastal inundation in New York City. The flood risk for New York City due to tropical cyclones and their resultant storm surges has increased significantly during the last millennium. Mean flood heights increased by >1.2 m from ∼A.D. 850 to A.D. 2005 due to rising relative sea levels. Additionally, there were increases in the types of tropical cyclones that produce the greatest surges for the region. Subsequently, the 500-y flood height return periods have fallen to ∼24.4 y throughout the millennium.
Evolution of moth sex pheromone composition by a single amino acid substitution in a fatty acid desaturase
Authors: Buček Aleš , Matoušková Petra , Vogel Heiko , Šebesta Petr , Jahn Ullrich , Weißflog Jerrit , Svatoš Aleš , Pichová Iva
Published: September 2015

Significance

The diversity of sex pheromones (SPs) is pivotal to insect reproductive isolation and speciation. However, knowledge of molecular mechanisms of pheromone evolution is limited. The
Manduca sexta
SP contains unique triunsaturated fatty acid (3UFA) derivatives and represents thus a suitable model for the investigation of chemical communication evolution via recruitment of novel SP components. Here, we demonstrate that gene duplication and a single amino acid substitution in fatty acid desaturase (FAD) catalyzing production of diunsaturated moth pheromone precursors is sufficient for acquisition of 3UFA SP component precursors. Our study indicates that the potential for change in the moth pheromone composition is underlined by the inherent evolvability of pheromone biosynthetic FADs.
Ubiquitin systems mark pathogen-containing vacuoles as targets for host defense by guanylate binding proteins
Authors: Haldar Arun K. , Foltz Clémence , Finethy Ryan , Piro Anthony S. , Feeley Eric M. , Pilla-Moffett Danielle M. , Komatsu Masaki , Frickel Eva-Maria , Coers Jörn
Published: September 2015

Significance

The innate immune system protects the host against infections with a diverse set of microbes that include intracellular bacterial and protozoan pathogens residing within pathogen-containing vacuoles (PVs). Because PVs provide an intracellular niche permissive for microbial growth, their destruction is critical for host defense. In mammals, PV destruction is dependent on immunity-related GTPases and guanylate binding proteins (GBPs). Although it has been shown that GBPs translocate to and eliminate PVs, the mechanisms by which GBPs specifically bind to PVs were unknown. Here, we describe an immune pathway that results in the decoration of PVs with a small protein called ubiquitin. Ubiquitin-decorated PVs are subsequently recognized by GBPs, resulting in the elimination of PVs and their microbial inhabitants.
Modeling the effect of locus coeruleus firing on cortical state dynamics and single-trial sensory processing
Authors: Safaai Houman , Neves Ricardo , Eschenko Oxana , Logothetis Nikos K. , Panzeri Stefano
Published: September 2015

Significance

Understanding what makes a cortical neuron fire is fundamental to understand how neural circuits operate. We used simultaneous recordings from the locus coeruleus (the neuromodulatory nucleus releasing norepinephrine) and from the somatosensory cortex to formulate a mathematical model explaining how cortical responses originate from the interplay of the sensory drive that cortical neurons receive, the spontaneous dynamics of cortex, and the effect of neuromodulation. Our work provides a hypotheses about how the temporal structure of locus coeruleus burst firing regulates the amplitude and timing of changes in cortical excitability and may selectively amplify responses to salient sensory stimuli. It also suggests that downstream circuits may better decode the activity of a cortical sensory network after estimating its neuromodulatory state.
CCR4 promotes medullary entry and thymocyte–dendritic cell interactions required for central tolerance
Authors: Hu Zicheng , Lancaster Jessica N. , Sasiponganan Chayanit , Ehrlich Lauren I.R.
Published: September 2015

Autoimmunity results from a breakdown in central or peripheral tolerance. To establish central tolerance, developing T cells must enter the thymic medulla, where they scan antigen-presenting cells (APCs) displaying a diverse array of autoantigens. If a thymocyte is activated by a self-antigen, the cell undergoes either deletion or diversion into the regulatory T cell (T reg) lineage, thus maintaining self-tolerance. Mechanisms promoting thymocyte medullary entry and interactions with APCs are incompletely understood. CCR4 is poised to contribute to central tolerance due to its expression by post-positive selection thymocytes, and expression of its ligands by medullary thymic dendritic cells (DCs). Here, we use two-photon time-lapse microscopy to demonstrate that CCR4 promotes medullary entry of the earliest post-positive selection thymocytes, as well as efficient interactions between medullary thymocytes and DCs. In keeping with the contribution of thymic DCs to central tolerance, CCR4 is involved in regulating negative selection of polyclonal and T cell receptor (TCR) transgenic thymocytes. In the absence of CCR4, autoreactive T cells accumulate in secondary lymphoid organs and autoimmunity ensues. These studies reveal a previously unappreciated role for CCR4 in the establishment of central tolerance.
Geographic Expansion of Lyme Disease in the Southeastern United States, 2000–2014
Authors: Lantos Paul M. , Nigrovic Lise E. , Auwaerter Paul G. , Fowler Vance G. , Ruffin Felicia , Brinkerhoff R. Jory , Reber Jodi , Williams Carl , Broyhill James , Pan William K. , Gaines David N.
Published: September 2015

Background.  The majority of Lyme disease cases in the United States are acquired on the east coast between northern Virginia and New England. In recent years the geographic extent of Lyme disease has been expanding, raising the prospect of Lyme disease becoming endemic in the southeast.

Methods.  We collected confirmed and probable cases of Lyme disease from 2000 through 2014 from the Virginia Department of Health and North Carolina Department of Public Health and entered them in a geographic information system. We performed spatial and spatiotemporal cluster analyses to characterize Lyme disease expansion.

Results.  There was a marked increase in Lyme disease cases in Virginia, particularly from 2007 onwards. Northern Virginia experienced intensification and geographic expansion of Lyme disease cases. The most notable area of expansion was to the southwest along the Appalachian Mountains with development of a new disease cluster in the southern Virginia mountain region.

Conclusions.  The geographic distribution of Lyme disease cases significantly expanded in Virginia between 2000 and 2014, particularly southward in the Virginia mountain ranges. If these trends continue, North Carolina can expect autochthonous Lyme disease transmission in its mountain region in the coming years.
Survival after Perioperative Cardiopulmonary Resuscitation
Authors: Kalkman Shona , Hooft Lotty , Meijerman Johanne M. , Knape Johannes T. A. , van Delden Johannes J. M.
Published: September 2015

AbstractAbstract

Automatic suspension of do-not-resuscitate (DNR) orders during general anesthesia does not sufficiently address a patient’s right to self-determination and is a practice still observed among anesthesiologists today. To provide an evidence base for ethical management of DNR orders during anesthesia and surgery, the authors performed a systematic review of the literature to quantify the survival after perioperative cardiopulmonary resuscitation (CPR). Results show that the probability of surviving perioperative CPR ranged from 32.0 to 55.7% when measured within the first 24 h after arrest with a neurologically favorable outcome expectancy between 45.3 and 66.8% at follow-up, which suggests a viable survival of approximately 25%. Because CPR generally proves successful in less than 15% of out-of-hospital cardiac arrests, the altered outcome probabilities that the conditions in the operating room bring on warrant reevaluation of DNR orders during the perioperative period. By preoperatively communicating the evidence to patients, they can make better informed decisions while reducing the level of moral distress that anesthesiologists may experience when certain patients decide to retain their DNR orders.

The probability of surviving perioperative cardiopulmonary resuscitation is at least twice as high as in other settings, warranting reevaluation of do-not-resuscitate orders during the perioperative period in a preoperative conversation with the patient.
Challenges of LADA Diagnosis and Treatment: Lessons From 2 Case Reports
Authors: Chatzianagnostou Kyriazoula , Iervasi Giorgio , Vassalle Cristina
Published: September 2015

Latent autoimmune diabetes in adults (LADA) is a subtype of autoimmune diabetes, which shares characteristics of both Type 1 and 2 diabetes (T1D and T2D), and for this reason, it is often confused with other types of diabetes, misdiagnosed, and inappropriately treated. Two cases were presented (41-year-old and 50-year-old females), one occasionally diagnosed during routine health checkup, the other one identified as having T2D, and as far as misclassified and not optimally treated. Now, after approximately 9 months of LADA diagnosis, the first patient has an optimal metabolic control while maintaining the values of glycated hemoglobin to around 7% with small doses of analogue insulin (lispro 4–6 UI) before meals and long acting insulin (glargine 4–6 UI) at bedtime. The second patient, after approximately 2 years from the LADA diagnosis, has an optimal metabolic control, with maintenance of glycated hemoglobin to around 6.5%, and stable C-peptide level (around 1.5 ng/mL), only with dietary and exercise habits. To avoid misclassification, any patient who does not fit the typical T2D profile, or with poor glycemic control, and who does not follow the expected clinical course, as become insulin dependent sooner than expected, should be investigated to exclude LADA. To define the best therapeutic approach, each patient must be evaluated and therapy tailored on his/her specific profile, considering as very low insulin doses may be effective to maintain a successful metabolic control and the only dietary approach may be sufficient until the insulin-secretory capacity remains good.
Liver Transplantation for Biliary Atresia
Authors: Arnon Ronen , Annunziato Rachel A. , D’Amelio Guiseppe , Chu Jaime , Shneider Benjamin L.
Published: September 2015

Objectives:

Liver transplantation (LT) in children with biliary atresia (BA) is often performed because of poor bile drainage, complications of biliary cirrhosis, or recurrent cholangitis. Poor bile drainage after a Kasai hepatoportoenterostomy is the primary driver for LT in infancy. The aim of the present study was to compare the clinical characteristics and outcome of first isolated liver transplantation for infants with BA who underwent transplant before 2 years of age (transplanted at infancy [TAI]) with children transplanted later in life (age 2–<18 years = transplanted at childhood [TAC]).

Methods:

Children with BA who underwent LT between 2002 and 2012 were identified from the United Network for Organ Sharing Standard Transplant Analysis and Research data set files.

Results:

A total of 1818 children underwent first isolated liver transplantation for BA (TAI 1408 [77.4%]; TAC 410 [22.6%]). One and 5‐year patient survival of the TAI and TAC patients was 95.2%, 93.8%, and 97.8 %, 97.1%, respectively (P < 0.01 for both periods). One and 5‐year graft survival of the TAI and TAC patients was 87.6%, 84.6 % and 93.2%, 90.7%, respectively (P < 0.01 for both periods). Removal from the waitlist for disease progression or death was significantly higher for TAI compared with TAC (120 patients [6.3%] vs 21 [3.7%], P = 0.02). Cold ischemic time was found to be the prognostic factor for death after LT in TAI, whereas being on life support was a poor prognostic factor in TAC by multivariate risk factor analysis.

Conclusions:

The vast majority of transplants for BA occur in children <2 years of age. Younger patients with BA had significantly higher waitlist and posttransplant mortality. Given the consistently poorer outcomes, there is an urgent need to find methods to improve bile drainage after the Kasai hepatoportoenterostomy.
A Randomized Controlled Trial of Positioning for Lumbar Puncture in Young Infants
Authors: Hanson Amy L. , Schunk Jeff E. , Corneli Howard M. , Soprano Joyce V.
Published: September 2015

Objective

The lateral and sitting positions are those most widely used to perform lumbar puncture (LP) in infants. This study sought to compare LP success rates by position. Secondary outcomes were successful LP on the first attempt and rates of procedural complications.

Methods

Infants aged 1 to 90 days undergoing LP in our pediatric emergency department between June 1, 2012 and October 31, 2013 were randomized to 1 position or the other. Successful LP was defined as collection of cerebrospinal fluid with a red blood cell count of less than 10,000 cells/mm3 on either of the first 2 attempts. Electronic medical records were reviewed for patient information, cerebrospinal fluid results, and procedural complications. Providers completed a questionnaire detailing their previous LP experience and technique. Primary results were analyzed using the intention-to-treat principle.

Results

We enrolled 168 infants. Of 167 with data eligible for analysis, 82 (49%) were randomized to the lateral position. There was no statistically significant difference in LP success rate between the lateral (77%, 63/82) and sitting (72%, 61/85) positions (difference, 5.1%; 95% confidence interval, −8.2%–18.3%). There were no significant differences in success on the first LP attempt or the rates of procedural complications.

Conclusions

Among infants 1 to 90 days of age, this study found no difference in LP success between the lateral and sitting positions.
Leucobacter zeae sp. nov., isolated from the rhizosphere of maize (Zea mays L.)
Authors: Lai Wei-An , Lin Shih-Yao , Hameed Asif , Hsu Yi-Han , Liu You-Cheng , Huang Hsuan-Ru , Shen Fo-Ting , Young Chiu-Chung
Published: September 2015

A novel yellow-pigmented, aerobic, rod-shaped, non-motile bacterium, designated strain CC-MF41T, was isolated from rhizosphere soil of maize (Zea mays) collected in Wufeng District, Taichung, Taiwan. Strain CC-MF41T exhibited 16S rRNA gene sequence similarity of 97.5, 97.3, 97.2 and 97.1 % to Leucobacter chironomi MM2LBT (and ‘Leucobacter kyeonggiensis’ F3-P9 and ‘L. humi’ Re-6, the names of which have not been validly published), Leucobacter tardus K70/01T, L. komagatae IFO 15245T and ‘Leucobacter margaritiformis’ A23. However, CC-MF41T and ‘L. margaritiformis’ A23 formed a loosely bound phylogenetic lineage (with a low bootstrap value) associated with species of the genus Leucobacter. In DNA–DNA reassociation experiments, the relatedness of strain CC-MF41T to L. chironomi DSM 19883T was 57.1 % (reciprocal value 29.1 %). The DNA G+C content of strain CC-MF41T was 72.1 mol% and the cell-wall peptidoglycan contained 2,4-diaminobutyric acid, alanine, glycine, glutamic acid and threonine. The major menaquinone was MK-11 and the predominant fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The polar lipid profile of strain CC-MF41T contained major amounts of diphosphatidylglycerol followed by an unidentified glycolipid, phosphatidylglycerol and an unknown phospholipid. Based on its phylogenetic, phenotypic and chemotaxonomic distinctiveness, strain CC-MF41T represents a novel species of Leucobacter, for which the name Leucobacter zeae sp. nov. is proposed. The type strain is CC-MF41T ( = BCRC 80515T = LMG 27265T).
Paenibacillus ripae sp. nov., isolated from bank side soil
Authors: Sun Ying , Guo Zhaohui , Zhao Qi , Gao Qiyu , Xie QinJian , Yang Rui , Liu Ronghui , Wu Zhengrong , Chen Peng , Li Yang , Wang Xin , Li Hongyu
Published: September 2015

A Gram-stain-variable, rod-shaped, non-motile and endospore-forming bacterium, designated strain HZ1T, was isolated from a sample of bank side soil from Hangzhou city, Zhejiang province, PR China. On the basis of 16S rRNA gene sequence analysis, strain HZ1T was closely related to members of the genus Paenibacillus, sharing the highest levels of sequence similarity with Paenibacillus agarexedens DSM 1327T (94.4 %), Paenibacillus sputi KIT00200-70066-1T (94.4 %). Growth occurred at 15–42 °C (optimum 30–37 °C), pH 5.0–9.5 (optimum pH 7.0–8.0) and NaCl concentrations of up to 6.0 % (w/v) were tolerated (optimum 0.5 %). The dominant respiratory quinone was MK-7 and the DNA G+C content was 40.1 mol%. The major fatty acids were anteiso-C15 : 0 and iso-C16 : 0. The major polar lipids of strain HZ1T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and several unknown lipids. The diagnostic diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. Based on its phenotypic and chemotaxonomic characteristics and phylogenetic data, strain HZ1T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus ripae sp. nov. (type strain HZ1T = CCTCC AB 2014276T = LMG 28639T) is proposed.
Thermocrinis jamiesonii sp. nov., a thiosulfate-oxidizing, autotropic thermophile isolated from a geothermal spring
Authors: Dodsworth Jeremy A. , Ong John C. , Williams Amanda J. , Dohnalkova Alice C. , Hedlund Brian P.
Published: September 2015

An obligately thermophilic, chemolithotrophic, microaerophilic bacterium, designated strain GBS1T, was isolated from the water column of Great Boiling Spring, Nevada, USA. Thiosulfate was required for growth. Although capable of autotrophy, growth of GBS1T was enhanced in the presence of acetate, peptone or Casamino acids. Growth occurred at 70–85 °C with an optimum at 80 °C, at pH 6.50–7.75 with an optimum at pH 7.25, with 0.5–8 % oxygen with an optimum at 1–2 % and with ≤ 200 mM NaCl. The doubling time under optimal growth conditions was 1.3 h, with a final mean cell density of 6.2 ± 0.5 × 107 cells ml− 1. Non-motile, rod-shaped cells 1.4–2.4 × 0.4–0.6 μm in size occurred singly or in pairs. The major cellular fatty acids (>5 % of the total) were C20 : 1ω9c, C18 : 0, C16 : 0 and C20 : 0. Phylogenetic analysis of the GBS1T 16S rRNA gene sequence indicated an affiliation with Thermocrinis ruber and other species of the genus Thermocrinis, but determination of 16S rRNA gene sequence similarity ( ≤ 97.10 %) and in silico estimated DNA–DNA hybridization values ( ≤ 18.4 %) with the type strains of recognized Thermocrinis species indicate that the novel strain is distinct from described species. Based on phenotypic, genotypic and phylogenetic characteristics, a novel species, Thermocrinis jamiesonii sp. nov., is proposed, with GBS1T ( = JCM 19133T = DSM 27162T) as the type strain.
Cryptococcus gattii: immunological and microbiological study in a patient with neurocryptococcosis
Authors: de Moraes Vasconcelos Dewton , Domingues-Ferreira Maurício , Soares Maria Cecília Pereira , dos Anjos Martins Marilena , de Almeida Bezerra Thiago , Paula Claudete Rodrigues , Auler Marcos Ereno
Published: September 2015

Introduction:

Cryptococcal meningitis is a disease that remains a significant cause of morbidity and mortality. This report describes the importance of conducting a detailed clinical investigation and the treatment challenges in cases of meningitis caused by Cryptococcus gattii. In recent years this species has received considerable interest due to its increased emergence and virulence.

Case presentation:

A patient with apparent good health (a fitness practitioner) showed symptoms including intermittent headache that became more intense and frequent when he began experiencing nausea, vomiting, dizziness and temporal headache without nuchal rigidity. The patient had human immunodeficiency virus-negative serology and had no chronic disease. Analysis of cerebrospinal fluid was performed and cryptococcal meningitis was diagnosed. Immunophenotyping by flow cytometry evidenced the presence of an anomalous lymphoid population. RFLP analysis of the URA5 gene indicated Cryptococcus gattii genotype VGII and considerable virulence was observed for the isolated strain.

Conclusion:

This case suggests the importance of a detailed investigation in patients who apparently have a competent immune system with meningitis caused by Cryptococcus spp., particularly C. gattii.
Lipopeptide biosurfactant viscosin enhances dispersal of Pseudomonas fluorescens SBW25 biofilms
Authors: Bonnichsen Lise , Bygvraa Svenningsen Nanna , Rybtke Morten , de Bruijn Irene , Raaijmakers Jos M. , Tolker-Nielsen Tim , Nybroe Ole
Published: September 2015

Pseudomonads produce several lipopeptide biosurfactants that have antimicrobial properties but that also facilitate surface motility and influence biofilm formation. Detailed studies addressing the significance of lipopeptides for biofilm formation and architecture are rare. Hence, the present study sets out to determine the specific role of the lipopeptide viscosin in Pseudomonas fluorescens SBW25 biofilm formation, architecture and dispersal, and to relate viscA gene expression to viscosin production and effect. Initially, we compared biofilm formation of SBW25 and the viscosin-deficient mutant strain SBW25ΔviscA in static microtitre assays. These experiments demonstrated that viscosin had little influence on the amount of biofilm formed by SBW25 during the early stages of biofilm development. Later, however, SBW25 formed significantly less biofilm than SBW25ΔviscA. The indication that viscosin is involved in biofilm dispersal was confirmed by chemical complementation of the mutant biofilm. Furthermore, a fluorescent bioreporter showed that viscA expression was induced in biofilms 4 h prior to dispersal. Subsequent detailed studies of biofilms formed in flow cells for up to 5 days revealed that SBW25 and SBW25ΔviscA developed comparable biofilms dominated by well-defined, mushroom-shaped structures. Carbon starvation was required to obtain biofilm dispersal in this system. Dispersal of SBW25 biofilms was significantly greater than of SBW25ΔviscA biofilms after 3 h and, importantly, carbon starvation strongly induced viscA expression, in particular for cells that were apparently leaving the biofilm. Thus, the present study points to a role for viscosin-facilitated motility in dispersal of SBW25 biofilms.
On the causes of evolutionary transition:transversion bias
Authors: Stoltzfus Arlin , Norris Ryan W.
Published: September 2015

A pattern in which nucleotide transitions are favored several-fold over transversions is common in molecular evolution. When this pattern occurs among amino acid replacements, explanations often invoke an effect of selection, on the grounds that transitions are more conservative in their effects on proteins. However, the underlying hypothesis of conservative transitions has never been tested directly. Here we assess support for this hypothesis using direct evidence: the fitness effects of mutations in actual proteins, measured via individual or paired growth experiments. We assembled data from 8 published studies, ranging in size from 24 to 757 single-nucleotide mutations that change an amino acid. Every study has the statistical power to reveal significant effects of amino acid exchangeability, and most studies have the power to discern a binary conservative-vs-radical distinction. However, only one study suggests that transitions are significantly more conservative than transversions. In the combined set of 1239 replacements, the chance that a transition is more conservative than a transversion is 53 % (95 % confidence interval, 50 % to 56 %), compared to the null expectation of 50 %. We show that this effect is not large compared to that of most biochemical factors, and is not large enough to explain the several-fold bias observed in evolution. In short, available data have the power to verify the "conservative transitions" hypothesis if true, but suggest instead that selection on proteins plays at best a minor role in the observed bias.
Structural basis for amino-acid recognition and transmembrane signalling by tandem Per–Arnt–Sim (tandem PAS) chemoreceptor sensory domains
Authors: Liu Yu C. , Machuca Mayra A. , Beckham Simone A. , Gunzburg Menachem J. , Roujeinikova Anna
Published: September 2015

Chemotaxis, mediated by methyl-accepting chemotaxis protein (MCP) receptors, plays an important role in the ecology of bacterial populations. This paper presents the first crystallographic analysis of the structure and ligand-induced conformational changes of the periplasmic tandem Per-Arnt-Sim (PAS) sensing domain (PTPSD) of a characterized MCP chemoreceptor. Analysis of the complex of theCampylobacter jejuniTlp3 PTPSD with isoleucine (a chemoattractant) revealed that the PTPSD is a dimer in the crystal. The two ligand-binding sites are located in the membrane-distal PAS domains on the faces opposite to the dimer interface. Mutagenesis experiments show that the five strongly conserved residues that stabilize the main-chain moiety of isoleucine are essential for binding, suggesting that the mechanism by which this family of chemoreceptors recognizes amino acids is highly conserved. Although the fold and mode of ligand binding of the PTPSD are different from the aspartic acid receptor Tar, the structural analysis suggests that the PTPSDs of amino-acid chemoreceptors are also likely to signal by a piston displacement mechanism. The PTPSD fluctuates between piston (C-terminal helix) `up' and piston `down' states. Binding of an attractant to the distal PAS domain locks it in the closed form, weakening its association with the proximal domain and resulting in the transition of the latter into an open form, concomitant with a downward (towards the membrane) 4 Å piston displacement of the C-terminal helix.In vivo, this movement would generate a transmembrane signal by driving a downward displacement of the transmembrane helix 2 towards the cytoplasm.
Towards phasing using high X-ray intensity
Authors: Galli Lorenzo , Son Sang-Kil , Barends Thomas R. M. , White Thomas A. , Barty Anton , Botha Sabine , Boutet Sébastien , Caleman Carl , Doak R. Bruce , Nanao Max H. , Nass Karol , Shoeman Robert L. , Timneanu Nicusor , Santra Robin , Schlichting Ilme , Chapman Henry N.
Published: September 2015

X-ray free-electron lasers (XFELs) show great promise for macromolecular structure determination from sub-micrometre-sized crystals, using the emerging method of serial femtosecond crystallography. The extreme brightness of the XFEL radiation can multiply ionize most, if not all, atoms in a protein, causing their scattering factors to change during the pulse, with a preferential `bleaching' of heavy atoms. This paper investigates the effects of electronic damage on experimental data collected from a Gd derivative of lysozyme microcrystals at different X-ray intensities, and the degree of ionization of Gd atoms is quantified from phased difference Fourier maps. A pattern sorting scheme is proposed to maximize the ionization contrast and the way in which the local electronic damage can be used for a new experimental phasing method is discussed.
Full elastic strain and stress tensor measurements from individual dislocation cells in copper through-Si vias
Authors: Levine Lyle E. , Okoro Chukwudi , Xu Ruqing
Published: September 2015

Nondestructive measurements of the full elastic strain and stress tensors from individual dislocation cells distributed along the full extent of a 50 µm-long polycrystalline copper via in Si is reported. Determining all of the components of these tensors from sub-micrometre regions within deformed metals presents considerable challenges. The primary issues are ensuring that different diffraction peaks originate from the same sample volume and that accurate determination is made of the peak positions from plastically deformed samples. For these measurements, three widely separated reflections were examined from selected, individual grains along the via. The lattice spacings and peak positions were measured for multiple dislocation cell interiors within each grain and the cell-interior peaks were sorted out using the measured included angles. A comprehensive uncertainty analysis using a Monte Carlo uncertainty algorithm provided uncertainties for the elastic strain tensor and stress tensor components.
Crystal structure of an unknown tetrahydrofuran solvate of tetrakis(μ3-cyanato-κ3N:N:N)tetrakis[(triphenylphosphane-κP)silver(I)]
Authors: Frenzel Peter , Schaarschmidt Dieter , Jakob Alexander , Lang Heinrich
Published: September 2015

In the title compound, [{[(C6H5)3P]Ag}4{NCO}4], a distorted Ag4N4-heterocubane core is set up by four AgIions being coordinated by the N atoms of the cyanato anions in aμ3-bridging mode. In addition, a triphenylphosphine ligand is datively bonded to each of the AgIions. Intramolecular Ag...Ag distances as short as 3.133 (9) Å suggest the presence of argentophilic (d10...d10) interactions. Five moderate-to-weak C—H...O hydrogen-bonding interactions are observed in the crystal structure, spanning a three-dimensional network. A region of electron density was treated with the SQUEEZE procedure inPLATON[Spek (2015).Acta Cryst.C71, 9–18] following unsuccessful attempts to model it as being part of disordered tetrahydrofuran solvent molecules. The given chemical formula and other crystal data do not take into account these solvent molecules.
Knowledge-intensive process management: a case study from the public sector
Authors: Manfreda Anton , Buh Brina , Indihar Štemberger Mojca
Published: September 2015

Purpose

– There is very little literature about improving and managing knowledge-intensive business processes (KIBPs). Since innovation plays an important role in knowledge work, these processes are different from traditional business processes, for which most business process management (BPM) methods have been developed, and therefore KIBPs should be improved differently. The purpose of this paper is to contribute to the understanding of BPM in the case of KIBPs by describing some methods that can be applied to manage and improve KIBPs.

Design/methodology/approach

– The paper presents a case study of a BPM project in the public sector, where most processes are knowledge-intensive. In conducting the longitudinal case study, established guidelines for interpretive case study research were followed. Both qualitative and quantitative data were collected.

Findings

– The paper presents some findings about the methods that can be applied for BPM in the case of KIBPs. It shows that the main phases of a BPM project can be the same as in a typical project; however, within each project phase different methods have to be applied. Appropriate methods for modelling the existing processes were workshops and interviews. Qualitative methods were suitable for the analysis phase, while it was not necessary to develop detailed to-be models in the business process redesign phase.

Originality/value

– The paper contributes to the body of knowledge on BPM in the case of KIBPs. Previous findings from the literature claiming that participative, incremental and continuous methods are suitable for improving KIBPs were confirmed. The case study also showed that proper project management, communication, the active role of top management and the involvement of external consultants during BPM projects are very important.
General managers’ environmental commitment and environmental involvement of lodging companies
Authors: Kim Hyun Jeong , Park Jeongdoo , Wen Ji
Published: September 2015

Purpose

– The purpose of this paper is to test links from hotel general managers’ (GMs’) environmental commitment to hotel companies’ environmental management capabilities and then to hotel companies’ involvement in environmental practices. The secondary goal of this study is to identify the common, critical environmental management capabilities in the lodging business context.

Design/methodology/approach

– In total, 172 GMs, working for hotels affiliated with two state lodging associations located in the northwest region of the USA, participated in this study. GMs’ responses were gathered via an online survey. The structural equation modeling was used to test the proposed model.

Findings

– The results show that GMs’ environmental commitment affects their firms’ involvement in environmental practices both directly (GMs’ commitment and firms’ involvement) and indirectly via firms’ environmental management capabilities (GMs’ commitment, firms’ capabilities and firms’ involvement). The five common, critical hotel environmental management capabilities are identified: employee training, communicating environmental initiatives to guests, knowledge and skills to implement environmental practices, capital to invest in environmental management and support from employees.

Practical implications

– The hotel industry-specific environmental management capabilities enhance hotel practitioners’ understanding of the critical components for the success of hotel environmental programs and assist GMs to effectively prepare and operate their hotels’ environmental initiatives.

Originality/value

– This study demonstrates the essential role of individual actors, specifically hotel GMs, in firms’ environmental involvement, and advances our understanding of hotel environmental management in hospitality literature.
How online search behavior is influenced by user-generated content on review websites and hotel interactive websites
Authors: Herrero Ángel , San Martín Héctor , Hernández José  M.
Published: September 2015

Purpose

– The purpose of this paper is to advance in research on consumer psychology of hospitality, since it investigates how online search behavior of users (particularly, information search and choice) is influenced by the opinions of other people in a new context characterized by the generalized use of Web 2.0 applications.

Design/methodology/approach

– Empirical research was carried out in the hotel sector in Iberian Peninsula, where two Web 2.0 applications are especially relevant for users: the review Web sites and the hotel interactive Web sites. A qualitative method (in-depth interviews with hotel managers) and a quantitative technique (personal surveys to a sample of 830 users) were used to conduct this research.

Findings

– The results indicates that the perceived influence on behavior of the user-generated content on these Web 2.0 applications is determined, in both cases, by the value of the information, the credibility of the sources and the degree of similarity between the user and the creators of content.

Practical implications

– Firms should have an active presence in the review Web sites and the hotel interactive Web sites, and use these platforms for market research and communication. Firms should engage users to post content, support their credibility and facilitate the evaluation of the content generators’ similarity.

Originality/value

– This paper is the first study in the hospitality literature that develops and empirically tests an integrative model explaining the perceived influence on behavior of user-generated content on Web 2.0 applications.
Internet marketing research in hospitality and tourism: a review and journal preferences
Authors: Leung Xi Yu , Xue Lan , Bai Billy
Published: September 2015

Purpose

– The purpose of this study is to provide a progress review of published Internet marketing research within the top eight hospitality and tourism journals and to provide suggestions on future research directions.

Design/methodology/approach

– The study collected 331 Internet marketing-related articles published in the top eight hospitality and tourism journals during the period of 1996-2013. Using content analysis, the study analyzed and discussed research topics, research methods and industry sectors of selected articles. The study period was broken into three sub-periods and used correspondence analysis (CA) to examine the significant changes of topical areas over time. A follow-up CA was conducted to compare the topical and methodological preferences of the selected eight journals.

Findings

– In all, 5-category and 27-subcategory classifications of research topics were identified in the study. The two-dimensional perceptual map indicates that Internet marketing research in the hospitality and tourism fields experienced introduction, growth and maturity stages. The research focus changed from business perspective to customer perspective and then to both business and customer perspectives. The eight top hospitality and tourism journals were grouped into four journal sets that share similar article characteristics and preferences.

Research limitations/implications

– Due to the sample size, the classifications and trends generated in this study may not be generalized to all Internet marketing research in hospitality and tourism disciplines. The process of identifying topic and method categories might be biased, especially in identifying new topics. Future research may apply CA method in literature review studies on other research topics.

Practical implications

– The study analyzed published research in Internet marketing in the hospitality and tourism fields and provided topical and methodological recommendations to academia for future research. This study may also give hospitality managers new insights into Internet marketing applications in the industry.

Originality/value

– This study is one of the few attempts to provide a comprehensive review of Internet marketing research in the hospitality and tourism fields. This study uses CA in literature review study, opening up a new way to easily analyze and visually display the literature trends. This study also creatively compared the publication preferences among eight top-tier hospitality and tourism journals using correspondence analysis.