bluuebunny/crossref_metadata_2025 huggingface dataset:
Mycorrhizal traits and plant communities: perspectives for integration
Authors: Moora Mari
Published: March 2014

Plant functional type‐ and trait‐based approaches to understanding vegetation dynamics are gradually gaining popularity. However, plant mycorrhizal traits are rarely considered in plant trait databases and are almost totally neglected in trait‐based plant community studies, despite more than 90% of the land flora being mycorrhizal. In this paper I describe and define the mycorrhizal traits of plant species, notably mycorrhizal type, mycorrhizal status, mycorrhizal flexibility and mycorrhizal dependency, which potentially influence plant distribution and community structure. I propose ways of using these traits for large‐scale synthetic studies for understanding the role of mycorrhizal symbiosis in vegetation dynamics. I suggest considering plant community mycorrhization – community means of mycorrhizal traits weighted by plant species abundances – and suggest an index of mycorrhization to describe the mycorrhizal trait composition of plant communities.
Trait‐mediated effects between predators: ant chemical cues induce spider dispersal
Authors: Mestre L. , Bucher R. , Entling M. H.
Published: March 2014

Predators can induce changes in prey phenotype such as dispersal, activity and foraging rate. Such trait‐mediated effects (TMEs) can strongly affect prey populations and generate trophic cascades, rivaling the importance of predation in communities. However, the relevance of TME on intraguild interactions has rarely been addressed. Ants and spiders are widespread generalist predators in terrestrial habitats. Ants influence arthropod assemblages and disrupt top‐down effects of spiders on herbivores by killing spiders and/or by inducing spider emigration. Here, we examined whether ants induce dispersal behaviour in spiders. We tested the effect of chemical cues of two ant species (Lasius niger, Formica clara) on the walking activity and the propensity for silk‐based dispersal of spiders. Silk‐based dispersal of the web‐builder Phylloneta impressa increased by 80% with exposure to Lasius cues, whereas dispersal of the hunting spider Xysticus more than doubled when confronted with cues of both Lasius and Formica. In addition, Xysticus individuals showed a marked increase in walking activity when exposed to Formica but not Lasius cues. Our results show for the first time that perceived predation risk influences spider dispersal. The strong effect of ant chemical cues on spider dispersal demonstrates that TMEs contribute to the impact of ants on arthropod communities.
Effects of spatiotemporal resource heterogeneity on home range size of American beaver
Authors: McClintic L. F. , Taylor J. D. , Jones J. C. , Singleton R. D. , Wang G.
Published: March 2014

Home range size of terrestrial animals may be influenced by spatiotemporal dynamics of resources. However, little is known regarding the effects of spatiotemporal resource availability on semi‐aquatic central place foragers such as the American beaver Castor canadensis. From January 2011 to April 2012, 26 beavers at 11 wetlands at Redstone Arsenal in north‐central Alabama, USA, were captured and radio‐tracked using radio telemetry. The objectives of this study were to test the predictions of three hypotheses: (1) the resource dispersion hypothesis: more spatially dispersed resources throughout a landscape increase home range sizes; (2) the temporal resource variability hypothesis: more temporally variable resources result in decreases in home range sizes; (3) the habitat productivity hypothesis: increases in habitat productivity lead to decreases in home range sizes. Twenty‐three of 26 radio‐tagged beavers had well‐bounded home ranges, and their home range sizes were positively related to the diversity of land cover within home ranges as predicted by the resource dispersion hypothesis. Furthermore, home range sizes of 26 beavers, including three seasonally dispersing beavers, decreased with increasing seasonal variability of within‐home‐range normalized difference vegetation index (NDVI), supporting the prediction of the resource heterogeneity hypothesis. Home range sizes of American beavers increased with increasing total NDVI and proportions of woody plant cover within home ranges probably to avoid overexploitation of woody plants. Our results suggest that the combination of resource quantity, spatial distribution and seasonal variation of resources influences movements and home ranges of central place foragers.
Coping with savanna seasonality: comparative daily activity patterns of African ungulates as revealed by GPS telemetry
Authors: Owen‐Smith N. , Goodall V.
Published: March 2014

Daily activity schedules and time budgets reveal how animals cope with changing environmental conditions in securing food and evading enemies. Theory suggests that animals in populations limited by food availability should be energy maximizers in their foraging time allocation, while those regulated by predation should minimize their mobile activity levels. We compared daily and seasonal variation in activity states among three species of grazing ungulates coexisting in the same region of Kruger National Park, South Africa, and for one of these species between regions differing in rainfall. These grazers differed in body size and digestive physiology, potentially affecting their activity patterns. Hourly movement rates recorded by GPS telemetry were partitioned among activity states by applying independent mixture models. All three species showed activity peaks during the early morning and late afternoon, while resting prevailed pre‐dawn as well as through midday. African buffalo showed the strongest diel variation in activity and greatest depression of midday activity, consistent with their large body size. Buffalo maintained similar levels of activity through the day and night, while zebra and sable antelope showed higher levels of diurnal than nocturnal activity. During the late dry season, zebra and coexisting sable, but not buffalo, showed elevated foraging and total mobile activity. Zebra devoted more time to foraging than both ruminants, consistent with greater food intake requirements for hindgut digestion. Sable antelope inhabiting the region with higher rainfall showed similar activity levels to the sable herd in the drier area, but slower rates of movement while foraging and travelling and less elevation in foraging time towards the end of the dry season. Observed patterns indicated subtly changing interplay among different constraints bearing on activity patterns over the diel and seasonal cycles, especially those related to digestive physiology. Simplistic concepts of energy maximization or time minimization were not supported.
Chemical signals in the echidna: differences between seasons, sexes, individuals and gland types
Authors: Harris R. L. , Holland B. R. , Cameron E. Z. , Davies N. W. , Nicol S. C.
Published: March 2014

Seasonally reproducing animals show many behavioural and physiological changes during the mating period, including increased signalling for mate attraction. Mammals often rely on chemical signals for communication and coordination of mating and other social behaviours, but our understanding of the subtleties and functions of mammalian signalling could be increased with more input from non‐model systems. We used gas chromatography–mass spectrometry and non‐parametric statistics to investigate the volatile and non‐volatile composition of odorous secretions in an egg‐laying mammal (monotreme), the short‐beaked echidna Tachyglossus aculeatus. We collected a total of 778 odorant samples from 69 wild, sexually mature individuals over 3 years at our field site in southern Tasmania. Animals were sampled during the breeding and non‐breeding seasons, as well as during hibernation. Odorants included swabs from the cloaca and ‘waxy’ secretions from putative scent glands in the cloacal wall and at the base of the spurs. Chemical profiles varied between different gland secretions and by sex and season. Female spur and cloacal wax secretion profiles had higher relative abundances of sterols, whereas male wax secretion profiles had more long chain fatty acids. Male spur secretions changed significantly during the mating season and could function in intra‐sexual competition or female mate choice. Echidna scent gland secretions also varied between individuals, suggesting olfactory cues could be used for individual recognition. Our results indicate that echidna secretions contain information that could be used by individuals to attract and locate mates during the breeding season. We also provide evidence for the potential importance of compounds traditionally classified as ‘non‐volatile’, including sterols and fatty acids, as cues for individual recognition or mate assessment.
A study of the methodological and clinical validity of the combined lactulose hydrogen breath test with scintigraphic oro‐cecal transit test for diagnosing small intestinal bacterial overgrowth in IBS patients
Authors: Zhao J. , Zheng X. , Chu H. , Zhao J. , Cong Y. , Fried M. , Fox M. , Dai N.
Published: March 2014

Background

Small intestinal bacterial overgrowth (SIBO) may be a cause of irritable bowel syndrome (IBS); however, current investigations have important limitations. We aimed to identify clinically relevant diagnostic criteria for SIBO based on lactulose hydrogen breath test (LHBT) alone and combined with scintigraphic measurement of oro‐cecal transit (SOCT).

Methods

Results of LHBT/SOCT investigation from 89 IBS patients and 13 healthy volunteers were included in a systematic analysis of six published criteria for SIBO diagnosis. Clinical relevance of competing criteria was determined by assessing (i) prevalence of SIBO in IBS patients and healthy volunteers (ii) if SIBO diagnosis predicted improvement in IBS symptoms in a prospective, pilot therapeutic trial of a non‐absorbable antibiotic (rifaximin 600 mg b.d.) in IBS patients.

Key Results

Reproducibility of SIBO diagnosis by combined LHBT/SOCT was near perfect. A ≥5 ppm H2 increase prior to appearance of cecal contrast was detected in more IBS patients than healthy volunteers (35/89 vs 1/13; p = 0.026), but not for other diagnostic criteria. IBS patients with SIBO, compared to those without SIBO, reported significantly greater improvement in abdominal symptoms following rifaximin therapy (p < 0.002 overall IBS symptom severity). This improvement was most marked in D‐IBS patients in whom all symptoms improved, including stool frequency and consistency (all p < 0.004).

Conclusions & Inferences

Combined LHBT/SOCT testing using a H2 5 ppm cutoff may identify a subgroup of IBS patients with SIBO. Pilot data examining the clinical response to rifaximin suggest that this subset of IBS patients may benefit more than those with a normal test.
Herpes Zoster Duplex Bilateralis in an Immunocompetent Adolescent Boy: A Case Report and Literature Review
Authors: Yan Chen , Laguna Benjamin A. , Marlowe Lauren E. , Keller Michael D. , Treat James R.
Published: March 2014

Simultaneous involvement of herpes zoster in multiple dermatomes is uncommon, and even more so in immunocompetent individuals. We report a case wherein a healthy adolescent boy presented with herpes zoster in two distinct dermatomes, raising concern for immunodeficiency, but he was found to be immunocompetent on further testing. A 14‐year‐old boy with no significant past medical history developed painless vesicular eruptions in two distinct distributions. Varicella zoster virus polymerase chain reaction was positive from unroofed vesicles in both regions. Initial laboratory studies disclosed abnormalities of unknown significance in natural killer (NK) cell percentage and function. The patient was treated with appropriate antiviral therapy. Repeat studies while healthy were not suggestive of an underlying NK cell defect. There are few case reports describing herpes zoster in two or more dermatomes in children. Previously described presentations most commonly occurred in the context of primary immunodeficiency, acquired immunodeficiency, or immunosuppressive medications. Because of the rarity of this presentation in immunocompetent patients, the authors recommend a thorough immune evaluation of all children presenting with isolated multidermatomal zoster.
Haploidentical parental hematopoietic stem cell transplantation in pediatric refractory Langerhans cell histiocytosis
Authors: Jun Yang , Quan Qin Mao , Bin Wang , Hua Zhu Guang , Li Zhang , Rui Zhang , Guang Jia Chen , Hao Ma Hong , Long Duan Yan , Jing Yang , Xuan Zhou
Published: March 2014

Children with MS‐LCH that fail to respond to conventional chemotherapy have poor outcomes. HSCT represents a potential salvage approach. It has been applied in over 50 cases in recent years. HSCT can achieve greater disease control than chemotherapy, but it carries a high risk of transplant‐related mortality; thus, the haploidentical parental HSCT is used infrequently in pediatric refractory LCH. We report the first successful haploidentical parental HSCT, with no T‐cell depletion, in two girls, aged 26 months and five months, with refractory MS‐LCH. The mothers were donors with 5/6 and 4/6 HLA matches, respectively. The conditioning regimen included busulfan + cyclophosphamide + etoposide + antithymocyte‐globulin ± fludarabine; the GVHD prophylaxis was based on cyclosporine + methotrexate ± mycophenolate‐mofetil ± zenapax. In both cases, the stem cells were sourced from peripheral blood and BM, which included CD34+ cells (13.17 × 106/kg and 40.23 × 106/kg, respectively). These patients survived and showed no signs of disease activity in 54‐ and 44‐month post‐HSCT follow‐ups. Our results indicated that, for patients that fail chemotherapy delivered early in the disease, but do not show organ dysfunction progression, it may be possible to achieve successful haploidentical parental HSCT with a strong myeloablative regimen.
Angiosarcoma successfully treated with liver transplantation and sirolimus
Authors: Xue Megan , Masand Prakash , Thompson Patrick , Finegold Milton , Leung Daniel H.
Published: March 2014

Malignant liver tumors represent approximately 1% of malignancies in children. HA is a high‐grade tumor of endothelial cells that is even more rare in the pediatric population. HA has a limited response to chemotherapy, radiation and resection with universal tumor recurrence with LT and nearly 100% mortality by 18 months. This is the first reported successful case of hepatic angiosarcoma in a child who was treated by LT in combination with sirolimus. Sirolimus antagonizes the mTOR pathway, which regulates cell proliferation, differentiation, and migration, and is being studied as an anti‐neoplastic agent for solid tumors.
Two Methods for Retrieving UV Index for All Cloud Conditions from Sky Imager Products or Total SW Radiation Measurements
Authors: Badosa Jordi , Calbó Josep , Mckenzie Richard , Liley Ben , González Josep‐Abel , Forgan Bruce , Long Charles N.
Published: March 2014

Cloud effects on UV Index (UVI) and total solar radiation (TR) as a function of cloud cover and sunny conditions (from sky images) as well as of solar zenith angle (SZA) are assessed. These analyses are undertaken for a southern‐hemisphere mid‐latitude site where a 10‐years dataset is available. It is confirmed that clouds reduce TR more than UV, in particular for obscured Sun conditions, low cloud fraction (<60%) and large SZA (>60°). Similarly, local short‐time enhancement effects are stronger for TR than for UV, mainly for visible Sun conditions, large cloud fraction and large SZA. Two methods to estimate UVI are developed: (1) from sky imaging cloud cover and sunny conditions, and (2) from TR measurements. Both methods may be used in practical applications, although Method 2 shows overall the best performance, as TR allows considering cloud optical properties. The mean absolute (relative) differences of Method 2 estimations with respect to measured values are 0.17 UVI units (6.7%, for 1 min data) and 0.79 Standard Erythemal Dose (SED) units (3.9%, for daily integrations). Method 1 shows less accurate results but it is still suitable to estimate UVI: mean absolute differences are 0.37 UVI units (15%) and 1.6 SED (8.0%).
The Impact of Visibility on Trade: Evidence from the World Cup
Authors: Bayar Omer , Schaur Georg
Published: March 2014

Success in the FIFA World Cup provides countries with substantial international visibility. This paper uses this information shock associated with the World Cup to show that visibility has a significant impact on trade flows. In isolating the visibility effect, two identification problems are solved. Match outcomes in the World Cup are subject to significant uncertainty. This uncertainty, when combined with controls for economic development, makes World Cup success exogenous to exports. By contrast, hosting the World Cup is potentially endogenous owing to self‐selection issues. The paper exploits FIFA's host selection policy to construct exogenous instruments for hosting. The results show that success in the World Cup raises exports temporarily by around 5%.
Termination Theory and National Climate Change Mitigation Programs: The Case of New Zealand
Authors: Birchall S. Jeff
Published: March 2014

In 2008 New Zealand (NZ) changed from a Labour‐led to a National‐led government, and this resulted in a shift to government's carbon emission mitigation strategy, including the abandonment of the Communities for Climate Protection (CCP) and the Carbon Neutral Public Service (CNPS) programs. Using deLeon's seminal model for program termination, the objective of this research is to determine why NZ's newly elected government discontinued these initiatives. This empirical research is investigative and probing, and comprises a series of semi‐structured interviews with senior managers responsible for the delivery of the respective program within their organization. The architects of each program are also investigated. In the end, this study finds that while economic constraints and programmatic inefficiencies may have played a contributing role, political ideology is the primary rationale for the termination of the CNPS and the CCP‐NZ programs.
Understanding a Period of Policy Change: The Case of Hydraulic Fracturing Disclosure Policy in Colorado
Authors: Heikkila Tanya , Pierce Jonathan J. , Gallaher Samuel , Kagan Jennifer , Crow Deserai A. , Weible Christopher M.
Published: March 2014

This paper investigates the beliefs and framing strategies of interest groups during a period of policy change and the factors explaining policy change. We develop propositions to explore questions concerning policy change primarily from the advocacy coalition framework as well as from other theorie. The propositions are tested by examining the promulgation of a Colorado regulation requiring the disclosure of chemicals used in hydraulic fracturing. Using coded data of documents published by organizations involved in the rulemaking process, we find divergence between industry and environmental groups on their beliefs concerning hydraulic fracturing, as well as their portraying themselves and each other as heroes, victims, and villains, but some convergence on their more specific beliefs concerning disclosure of chemicals. Interviews point to the importance of policy entrepreneurs, timing, a negotiated agreement, and learning for explaining policy change. The findings provide both theoretical and methodological insights into how and why policy changes.
Science and Politics in the Regulation of Genetically Modified Organisms in Brazil
Authors: Mitre Maya , Reis Bruno P. W.
Published: March 2014

This paper analyzes the regulation of genetically modified organisms (GMOs) in Brazil, focusing on the debates that preceded the enactment in 2005 of the current Biosafety Law and the factors (both domestic and international) that influenced the policy‐making process. More specifically, it identifies the social and governmental actors that influenced the congressional debates, showing how their interests and agenda were translated into two different institutional frameworks. Here, the policy outcome was what we call a “hybrid” and “conciliatory” regulatory model, which formally acknowledges the importance of both technical/scientific and social/political considerations in the evaluation of GMO biosafety and engages most of the stakeholders in the regulatory process. The new policy regime also establishes a middle ground between the conflicting demands of promoting agricultural development and protecting the country's biodiversity.
Early Adopters of Solar Panels in Developing Countries: Evidence from Tanzania
Authors: Smith Michael G. , Urpelainen Johannes
Published: March 2014

Who pioneers the adoption of solar home systems as a source of power in developing countries? While many scholars of electrification praise off‐grid options, evidence on their adoption from nationally representative surveys is lacking. We test existing and new hypotheses using the 2007 Tanzanian National Household Budget Survey. Since the survey is nationally representative and has more than 10,000 respondent households, it is ideal for our purposes. We find modest support for the notion that wealthier households adopt more readily than poorer ones. Surprisingly, electrified households adopt solar home systems more readily than other households, suggesting that solar home systems provide backup power. We further find that larger households adopt more readily than smaller ones and that a rural location or high education levels do not predict solar power use. These findings suggest that new policies are needed to promote solar home systems in poor and rural areas, where their development effectiveness is maximal.
Capturing the Multiple and Shifting Identities of Farm Women in the Northeastern United States
Authors: Brasier Kathryn J. , Sachs Carolyn E. , Kiernan Nancy Ellen , Trauger Amy , Barbercheck Mary E.
Published: March 2014

The identities of women on farms are shifting as more women enter farming and identify as farmers, as reflected by the 30 percent growth in women farmers in the U.S. census of agriculture (USDA 2009). This article draws from identity theory to develop a quantitative measure of the identities of farm women. The measure incorporates multiple roles farming women may perform and weights these roles by their salience to two farm identities, farm operator and farm partner. We use a sample of women on farms (n = 810) in the northeastern United States to assess the measures of role identity in relation to reported decision‐making authority, farm tasks, and farm and individual characteristics. The findings provide a multidimensional view of farming women in the northeastern United States, a far more complex view than traditional survey research has previously captured. This research provides a measure that other researchers can use to assess the multiple and shifting identities of farming women in other sections of the United States.
Right to health and global public health research: from tensions to synergy?
Authors: Ooms Gorik , Hammonds Rachel
Published: March 2014

“La santé publique est la science et l'art de prévenir les maladies, de prolonger la vie et de promouvoir la santé grâce aux efforts organisés de la société”, alors que “la loi internationale sur les droits de l'homme défini ce que les gouvernements peuvent faire de nous, ne peuvent pas faire de nous et devraient faire our nous”. Appliqué au droit à la santé, cela signifie, que la loi internationale sur les droits de l'homme
défini ce que les gouvernements devraient et ne devraient pas faire pour promouvoir la santé des personnes: ainsi, algré leurs origines très différentes les deux concepts sont assez similaires. Cet article explore les différences entre les deux concepts afin de mieux comprendre la tension naturelle entre eux. Deuxièmement, il examine comment cette tension est accrue quand les deux concepts interagissent à l’échelle mondiale, en analysant trois cas. Enfin, les implications possibles sur la couverture santé universelle sont considérées dans le cas où les chercheurs en santé publique et ceux sur le droit à la santé travailleraient ensemble.
Pneumocystis jirovecii colonisation in HIV‐positive and HIV‐negative subjects in Cameroon
Authors: Riebold D. , Enoh D. O. , Kinge T. N. , Akam W. , Bumah M. K. , Russow K. , Klammt S. , Loebermann M. , Fritzsche C. , Eyong J. E. , Eppel G. , Kundt G. , Hemmer C. J. , Reisinger E. C.
Published: March 2014

Objective

To determine the prevalence of Pneumocystis pneumonia (PCP), a major opportunistic infection in AIDS patients in Europe and the USA, in Cameroon.

Materials and methods

Induced sputum samples from 237 patients without pulmonary symptoms (126 HIV‐positive and 111 HIV‐negative outpatients) treated at a regional hospital in Cameroon were examined for the prevalence of Pneumocystis jirovecii by specific nested polymerase chain reaction (nPCR) and staining methods. CD4 counts and the history of antiretroviral therapy of the subjects were obtained through the ESOPE database system.

Results and conclusion

Seventy‐five of 237 study participants (31.6%) were colonised with Pneumocystis, but none showed active PCP. The Pneumocystis colonisation rate in HIV‐positive subjects was more than double that of HIV‐negative subjects (42.9% vs. 18.9%, P < 0.001). In the HIV‐positive group, the colonisation rate corresponds to the reduction in the CD4 lymphocyte counts. Subjects with CD4 counts >500 cells/μl were colonised at a rate of 20.0%, subjects with CD4 counts between 200 and 500 cells/μl of 42.5%, and subjects with CD4 counts <200 cells/μl of 57.1%. Colonisation with Pneumocystis in Cameroon seems to be comparable to rates found in Western Europe. Prophylactic and therapeutic measures against Pneumocystis should be taken into account in HIV care in western Africa.
A phylogenetic analysis of Pseudopaludicola (Anura) providing evidence of progressive chromosome reduction
Authors: Veiga‐Menoncello Ana C. P. , Lourenço Luciana B. , Strüssmann Christine , Rossa‐Feres Denise C. , Andrade Gilda V. , Giaretta Ariovaldo A. , Recco‐Pimentel Shirlei M.
Published: March 2014

Here, we present a molecular phylogenetic analysis of the Neotropical genus Pseudopaludicola focusing on species relationships including 11 of the 17 known species of Pseudopaludicola; several samples of Pseudopaludicola are not assigned to any species; and 34 terminal species as an outgroup. The study was based on the analysis of approximately 2.3 kb of the sequence of the mitochondrial 12S rRNA, tRNAval and 16S rRNA genes through maximum parsimony and Bayesian phylogenetic reconstruction approaches. Our results showed that Pseudopaludicola is a well‐supported monophyletic group organized into four major clades and confirmed that the assemblage of species that lack T‐shaped terminal phalanges is paraphyletic with respect to the P. pusilla Group. Chromosomal data mapped on the cladogram showed a direct correlation among the four clades and observed chromosome numbers (2n = 22, 20, 18 and 16) with a progressive reduction in the chromosome number. Overall, our findings suggest that some taxonomic changes are necessary and reinforce the need for a revision of the genus Pseudopaludicola.
Conceptual Design of an Exactly Straight Lifting Forging Manipulator
Authors: Ding Huafeng , Feng Zemin , Fu Hongye , Wang Yuanyuan
Published: March 2014

The gripper lifting track of a forging manipulator should keep as close to a straight line as possible, especially for the manufacturing of long or high-precision forged pieces. However, the lifting tracks of most forging manipulators are arc, such as DANGO & DIENENTHAL in Siegen (DDS) and Schloemann-SiemagAG Meer (SMS Meer). This paper proposes a new forging manipulator whose gripper lifting track is exactly a straight line. First, a planar 3-degrees-of-freedom (3-DOF) mechanism whose gripper moves along a straight line is proposed. Second, replace the lifting drive of the planar mechanism with a parallel mechanism which only generates one translation, and obtain a major-motion mechanism. Finally, a new forging manipulator is constructed based on this major-motion mechanism. The new manipulator has the advantages of exactly straight lifting, high load-bearing capacity, and decoupling the lifting from other motions. It not only can improve forging precision for long axial forged pieces but also make coordinated control of two forging manipulators much easier.
Enhancing Physical Performance in Male Volleyball Players with a Caffeine-Containing Energy Drink
Authors: Coso Juan Del , Pérez-López Alberto , Abian-Vicen Javier , Salinero Juan Jose , Lara Beatriz , Valadés David
Published: March 2014

There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.
Jumping and Hopping in Elite and Amateur Orienteering Athletes and Correlations to Sprinting and Running
Authors: Hébert-Losier Kim , Jensen Kurt , Holmberg Hans-Christer
Published: March 2014

Purpose:

Jumping and hopping are used to measure lower-body muscle power, stiffness, and stretch-shortening-cycle utilization in sports, with several studies reporting correlations between such measures and sprinting and/or running abilities in athletes. Neither jumping and hopping nor correlations with sprinting and/or running have been examined in orienteering athletes.

Methods:

The authors investigated squat jump (SJ), countermovement jump (CMJ), standing long jump (SLJ), and hopping performed by 8 elite and 8 amateur male foot-orienteering athletes (29 ± 7 y, 183 ± 5 cm, 73 ± 7 kg) and possible correlations to road, path, and forest running and sprinting performance, as well as running economy, velocity at anaerobic threshold, and peak oxygen uptake (VO2peak) from treadmill assessments.

Results:

During SJs and CMJs, elites demonstrated superior relative peak forces, times to peak force, and prestretch augmentation, albeit lower SJ heights and peak powers. Between-groups differences were unclear for CMJ heights, hopping stiffness, and most SLJ parameters. Large pairwise correlations were observed between relative peak and time to peak forces and sprinting velocities; time to peak forces and running velocities; and prestretch augmentation and forest-running velocities. Prestretch augmentation and time to peak forces were moderately correlated to VO2peak. Correlations between running economy and jumping or hopping were small or trivial.

Conclusions:

Overall, the elites exhibited superior stretch-shortening-cycle utilization and rapid generation of high relative maximal forces, especially vertically. These functional measures were more closely related to sprinting and/or running abilities, indicating benefits of lower-body training in orienteering.
A 1-Year Study of Endurance Runners: Training, Laboratory Tests, and Field Tests
Authors: Galbraith Andy , Hopker James , Cardinale Marco , Cunniffe Brian , Passfield Louis
Published: March 2014

Purpose:

To examine the training and concomitant changes in laboratory- and field-test performance of highly trained endurance runners.

Methods:

Fourteen highly trained male endurance runners (mean ± SD maximal oxygen uptake [VO2max] 69.8 ± 6.3 mL · kg−1 · min−1) completed this 1-y training study commencing in April. During the study the runners undertook 5 laboratory tests of VO2max, lactate threshold (LT), and running economy and 9 field tests to determine critical speed (CS) and the modeled maximum distance performed above CS (D′). The data for different periods of the year were compared using repeated-measures ANOVA. The influence of training on laboratory- and field-test changes was analyzed by multiple regression.

Results:

Total training distance varied during the year and was lower in May–July (333 ± 206 km, P = .01) and July–August (339 ± 206 km, P = .02) than in the subsequent January–February period (474 ± 188 km). VO2max increased from the April baseline (4.7 ± 0.4 L/min) in October and January periods (5.0 ± 0.4 L/min, P ≤ .01). Other laboratory measures did not change. Runners’ CS was lowest in August (4.90 ± 0.32 m/s) and highest in February (4.99 ± 0.30 m/s, P = .02). Total training distance and the percentage of training time spent above LT velocity explained 33% of the variation in CS.

Conclusion:

Highly trained endurance runners achieve small but significant changes in VO2max and CS in a year. Increases in training distance and time above LT velocity were related to increases in CS.
Pacing by Winners of a 161-km Mountain Ultramarathon
Authors: Hoffman Martin D.
Published: March 2014

Purpose:

To examine pacing among the most successful runners in the 161-km Western States Endurance Run (WSER) to determine if variations in segmental speed relate to performance, ambient temperature, and calendar year.

Methods:

Segmental speed and coefficient of variation (CV) in speed were analyzed for 10 race segments of 24 races from 1985 through 2013.

Results:

Segmental speeds did not differ between the eventual winners and lead runners and only differed between the 1st and 2nd finishers in the 2nd half of the race. Mean CV in speed was lower (P < .01) for the winners (12%) than for the other top-5 finishers (14–15%). CV in speed was related (r = .80, P = .006) to finish time for the fastest 10 finish times at the WSER. Multiple linearregression analysis revealed mean CV in speed for the top-5 runners to be related to maximum ambient temperature (coefficient =.14, P < .05) and calendar year (coefficient = –.086, P = .034).

Conclusions:

Mountain trail running is characterized by wide variations in speed, but the fastest times are achieved when speed fluctuations are limited. This is generally accomplished by the winners remaining relatively close behind the lead runners before taking the lead in the middle half of the race, and then avoiding slowing as much as the other top runners in the latter race stages. Variations in speed increase with high ambient temperatures, and the small decrease in segmental speed variability among top runners across the nearly 30 y of this study suggests that the best runners have improved at pacing this race.
Functional Network Pipeline Reveals Genetic Determinants Associated with in Situ Lymphocyte Proliferation and Survival of Cancer Patients
Authors: Mlecnik Bernhard , Bindea Gabriela , Angell Helen K. , Sasso Maria Stella , Obenauf Anna C. , Fredriksen Tessa , Lafontaine Lucie , Bilocq Amelie M. , Kirilovsky Amos , Tosolini Marie , Waldner Maximilian , Berger Anne , Fridman Wolf Herman , Rafii Arash , Valge-Archer Viia , Pagès Franck , Speicher Michael R. , Galon Jérôme
Published: March 2014

Genomic alterations result in changes of immune cell densities within the tumor.
TRANSLOCATION Project: How to Get Good Drugs into Bad Bugs
Authors: Stavenger Robert A. , Winterhalter Mathias
Published: March 2014

The TRANSLOCATION project aims to decipher how to help antibiotics penetrate
Gram-negative bacteria’s double-envelope defense.
Coxiella burnetii Type IV Secretion-Dependent Recruitment of Macrophage Autophagosomes
Authors: Winchell Caylin G. , Graham Joseph G. , Kurten Richard C. , Voth Daniel E.
Published: March 2014

Coxiella burnetii
is an intracellular Gram-negative bacterium that causes human Q fever, a flu-like disease that can progress to chronic, life-threatening endocarditis. In humans,
C. burnetii
infects alveolar macrophages and promotes phagosomal fusion with autophagosomes and lysosomes, establishing a unique parasitophorous vacuole (PV) in which to replicate. The pathogen uses a Dot/Icm type IV secretion system (T4SS) to deliver effector proteins to the host cytoplasm, where they alter cellular processes to benefit the pathogen. The T4SS is required for PV expansion and prevention of apoptosis, but little else is known about the role of the system during intracellular growth. Recent reports suggest that
C. burnetii
actively recruits autophagosomes to the PV to deliver nutrients to the pathogen and provide membrane for the expanding vacuole. In this study, we examined the role of the T4SS in mediating PV interactions with autophagosomes. We found that the autophagy-related proteins LC3 and p62 localized to wild-type PV but not to T4SS mutant organism-containing phagosomes in human macrophage-like cells, primary human alveolar macrophages, and Chinese hamster ovary cells. However, while lipidated LC3 levels were elevated regardless of T4SS activity, no p62 turnover was observed during
C. burnetii
growth in macrophages, suggesting that the pathogen recruits preformed autophagosomes. When the T4SS was activated 24 h after infection, autophagosome recruitment ensued, indicating that autophagosome interactions are dispensable for initial PV maturation to a phagolysosome-like compartment but are involved in vacuole expansion. Together, these results demonstrate that
C. burnetii
actively directs PV-autophagosome interactions by using the Dot/Icm T4SS.
Phenotypic Screening of a Targeted Mutant Library Reveals Campylobacter jejuni Defenses against Oxidative Stress
Authors: Flint Annika , Sun Yi-Qian , Butcher James , Stahl Martin , Huang Hongsheng , Stintzi Alain
Published: March 2014

During host colonization,
Campylobacter jejuni
is exposed to harmful reactive oxygen species (ROS) produced from the host immune system and from the gut microbiota. Consequently, identification and characterization of oxidative stress defenses are important for understanding how
C. jejuni
survives ROS stress during colonization of the gastrointestinal tract. Previous transcriptomic studies have defined the genes belonging to oxidant stimulons within
C. jejuni
. We have constructed isogenic deletion mutants of these identified genes to assess their role in oxidative stress survival. Phenotypic screening of 109 isogenic deletion mutants identified 22 genes which were either hypersensitive or hyposensitive to oxidants, demonstrating important roles for these genes in oxidant defense. The significance of these genes in host colonization was also assessed in an
in vivo
chick model of
C. jejuni
colonization. Overall, our findings identify an indirect role for motility in resistance to oxidative stress. We found that a nonmotile flagellum mutant, the Δ
motAB
mutant, displayed increased sensitivity to oxidants. Restoration of sensitivity to superoxide in the Δ
motAB
mutant was achieved by fumarate supplementation or tandem deletion of
motAB
with
ccoQ
, suggesting that disruption of the proton gradient across the inner membrane resulted in increased superoxide production in this strain. Furthermore, we have identified genes involved in cation transport and binding, detoxification, and energy metabolism that are also important factors in oxidant defense. This report describes the first isogenic deletion mutant library construction for screening of relevant oxidative stress defense genes within
C. jejuni
, thus providing a comprehensive analysis of the total set of oxidative stress defenses.
Identification of a Group B Streptococcal Fibronectin Binding Protein, SfbA, That Contributes to Invasion of Brain Endothelium and Development of Meningitis
Authors: Mu Rong , Kim Brandon J. , Paco Czarinah , Del Rosario Yvette , Courtney Harry S. , Doran Kelly S.
Published: March 2014

Group B
Streptococcus
(GBS) is currently the leading cause of neonatal meningitis. This is due to its ability to survive and multiply in the bloodstream and interact with specialized human brain microvascular endothelial cells (hBMEC), which constitute the blood-brain barrier (BBB). The exact mechanism(s) of GBS-BBB penetration is still largely unknown. We and others have shown that GBS interacts with components of the extracellular matrix. In this study, we demonstrate that GBS of representative serotypes binds immobilized and cell surface fibronectin and identify a putative fibronectin binding protein,
s
treptococcal
f
ibronectin
b
inding protein A (SfbA). Allelic replacement of
sfbA
in the GBS chromosome resulted in a significant decrease in ability to bind fibronection and invade hBMEC compared with the wild-type (WT) parental strain. Expression of SfbA in the noninvasive strain
Lactococcus lactis
was sufficient to promote fibronectin binding and hBMEC invasion. Furthermore, the addition of an antifibronectin antibody or an RGD peptide that blocks fibronectin binding to integrins significantly reduced invasion of the WT but not the
sfbA
-deficient mutant strain, demonstrating the importance of an SfbA-fibronectin-integrin interaction for GBS cellular invasion. Using a murine model of GBS meningitis, we also observed that WT GBS penetrated the brain and established meningitis more frequently than did the Δ
sfbA
mutant strain. Our data suggest that GBS SfbA plays an important role in bacterial interaction with BBB endothelium and the pathogenesis of streptococcal meningitis.
Clostridium perfringens Type A Enterotoxin Damages the Rabbit Colon
Authors: Garcia Jorge P. , Li Jihong , Shrestha Archana , Freedman John C. , Beingesser Juliann , McClane Bruce A. , Uzal Francisco A.
Published: March 2014

Clostridium perfringens
enterotoxin causes the gastrointestinal (GI) symptoms of
C. perfringens
type A food poisoning and CPE-associated non-food-borne human GI diseases. It is well established that CPE induces fluid accumulation and severe tissue damage in ligated small intestinal loops of rabbits and other animals. However, a previous study had also reported that CPE binds to rabbit colonic cells yet does not significantly affect rabbit colonic loops. To the contrary, the current study determined that treatment with 50 or 100 μg/ml of CPE causes significant histologic lesions and luminal fluid accumulation in rabbit colonic loops. Interestingly, a CPE-neutralizing monoclonal antibody blocked the development of CPE-induced histologic damage but not luminal fluid accumulation in these loops. Similar luminal fluid accumulation, without significant histologic damage, also occurred after treatment of colonic loops with heat-inactivated CPE, antibody alone, or bovine serum albumin (BSA), indicating that increased osmolarity was causing or contributing to fluid accumulation in CPE-treated colonic loops. Comparative studies revealed the similar development of histologic damage and luminal fluid accumulation in both small intestinal loops and colonic loops after as little as a 1-h treatment with 50 μg/ml of CPE. Consistent with the CPE sensitivity of the small intestine and colon, Western blotting detected CPE binding and large-complex formation in both organs. In addition, Western blotting demonstrated the presence of the high-affinity CPE receptors claudin-3 and -4 in both organs of rabbits, consistent with the observed toxin binding. Collectively, these results offer support for the possible involvement of the colon in CPE-mediated GI disease.
Identification of an Outer Membrane Lipoprotein Involved in Nasopharyngeal Colonization by Moraxella catarrhalis in an Animal Model
Authors: Wang Wei , Joslin Stephanie N. , Pybus Christine , Evans Amanda S. , Lichaa Flora , Brautigam Chad A. , Hansen Eric J.
Published: March 2014

Colonization of the human nasopharynx by
Moraxella catarrhalis
is presumed to involve attachment of this bacterium to the mucosa. DNA microarray analysis was used to determine whether attachment of
M. catarrhalis
to human bronchial epithelial (HBE) cells
in vitro
affected gene expression in this bacterium. Attachment affected expression of at least 454 different genes, with 163 being upregulated and 291 being downregulated. Among the upregulated genes was one (ORF113) previously annotated as encoding a protein with some similarity to outer membrane protein A (OmpA). The protein encoded by ORF113 was predicted to have a signal peptidase II cleavage site, and globomycin inhibition experiments confirmed that this protein was indeed a lipoprotein. The ORF113 protein also contained a predicted peptidoglycan-binding domain in its C-terminal half. The use of mutant and recombinant
M. catarrhalis
strains confirmed that the ORF113 protein was present in outer membrane preparations, and this protein was also shown to be at least partially exposed on the bacterial cell surface. A mutant unable to produce the ORF113 protein showed little or no change in its growth rate
in vitro
, in its ability to attach to HBE cells
in vitro
, or in its autoagglutination characteristics, but it did exhibit a reduced ability to survive in the chinchilla nasopharynx. This is the first report of a lipoprotein essential to the ability of
M. catarrhalis
to persist in an animal model.
Causes for the Persistence of Impact Factor Mania
Authors: Casadevall Arturo , Fang Ferric C.
Published: March 2014

Numerous essays have addressed the misuse of the journal impact factor for judging the value of science, but the practice continues, primarily as a result of the actions of scientists themselves. This seemingly irrational behavior is referred to as “impact factor mania.” Although the literature on the impact factor is extensive, little has been written on the underlying causes of impact factor mania. In this perspective, we consider the reasons for the persistence of impact factor mania and its pernicious effects on science. We conclude that impact factor mania persists because it confers significant benefits to individual scientists and journals. Impact factor mania is a variation of the economic theory known as the “tragedy of the commons,” in which scientists act rationally in their own self-interests despite the detrimental consequences of their actions on the overall scientific enterprise. Various measures to reduce the influence of the impact factor are considered.

IMPORTANCE
Science and scientists are currently afflicted by an epidemic of mania manifested by associating the value of research with the journal where the work is published rather than the content of the work itself. The mania is causing profound distortions in the way science is done that are deleterious to the overall scientific enterprise. In this essay, we consider the forces responsible for the persistence of the mania and conclude that it is maintained because it disproportionately benefits elements of the scientific enterprise, including certain well-established scientists, journals, and administrative interests. Our essay suggests steps that can be taken to deal with this debilitating and destructive epidemic.