bluuebunny/crossref_metadata_2025 huggingface dataset:
UV‐Bmediated metabolic rearrangements in poplar revealed by non‐targeted metabolomics
Authors: KALING MORITZ , KANAWATI BASEM , GHIRARDO ANDREA , ALBERT ANDREAS , WINKLER JANA BARBRO , HELLER WERNER , BARTA CSENGELE , LORETO FRANCESCO , SCHMITT‐KOPPLIN PHILIPPE , SCHNITZLER JÖRG‐PETER
Published: April 2014

Plants have to cope with various abiotic stresses includingUV‐Bradiation (280–315 nm).UV‐Bradiation is perceived by a photoreceptor, triggers morphological responses and primes plant defence mechanisms such as antioxidant levels, photoreapir or accumulation ofUV‐Bscreening pigments. As poplar is an important model system for trees, we elucidated the influence ofUV‐Bon overall metabolite patterns in poplar leaves grown under highUV‐Bradiation. Combining non‐targeted metabolomics with gas exchange analysis and confocal microscopy, we aimed understanding howUV‐Bradiation triggers metabolome‐wide changes, affects isoprene emission, photosynthetic performance, epidermal light attenuation and finally how isoprene‐free poplars adjust their metabolome underUV‐Bradiation. Exposure toUV‐Bradiation caused a comprehensive rearrangement of the leaf metabolome. Several hundreds of metabolites were up‐ and down‐regulated over various pathways. Our analysis, revealed the up‐regulation of flavonoids, anthocyanins and polyphenols and the down‐regulation of phenolic precursors in the first 36 h ofUV‐Btreatment. We also observed a down‐regulation of steroids after 12 h. The accumulation of phenolic compounds leads to a reduced light transmission inUV‐B‐exposed plants. However, the accumulation of phenolic compounds was reduced in non‐isoprene‐emitting plants suggesting a metabolic‐ or signalling‐based interaction between isoprenoid and phenolic pathways.
Isoprene production in transgenic tobacco alters isoprenoid, non‐structural carbohydrate and phenylpropanoid metabolism, and protects photosynthesis from drought stress
Authors: TATTINI MASSIMILIANO , VELIKOVA VIOLETA , VICKERS CLAUDIA , BRUNETTI CECILIA , DI FERDINANDO MARTINA , TRIVELLINI ALICE , FINESCHI SILVIA , AGATI GIOVANNI , FERRINI FRANCESCO , LORETO FRANCESCO
Published: April 2014

Isoprene strengthens thylakoid membranes and scavenges stress‐induced oxidative species. The idea that isoprene production might also influence isoprenoid and phenylpropanoid pathways under stress conditions was tested. We used transgenic tobacco to compare physiological and biochemical traits of isoprene‐emitting (IE) and non‐emitting (NE) plants exposed to severe drought and subsequent re‐watering. Photosynthesis was less affected by drought in IE than in NE plants, and higher rates were also observed in IE than in NE plants recovering from drought. Isoprene emission was stimulated by mild drought. Under severe drought, isoprene emission declined, and levels of non‐volatile isoprenoids, specifically de‐epoxidated xanthophylls and abscisic acid (ABA), were higher in IE than in NE plants. Soluble sugars and phenylpropanoids were also higher in IE plants. After re‐watering, IE plants maintained higher levels of metabolites, but isoprene emission was again higher than in unstressed plants. We suggest that isoprene production in transgenic tobacco triggered different responses, depending upon drought severity. Under drought, the observed trade‐off between isoprene and non‐volatile isoprenoids suggests that in IE plants isoprene acts as a short‐term protectant, whereas non‐volatile isoprenoids protect against severe, long‐term damage. After drought, it is suggested that the capacity to emit isoprene might up‐regulate production of non‐volatile isoprenoids and phenylpropanoids, which may further protect IE leaves.
Gonadotrophic hormone and reinforcement sensitivity systems in women with premenstrual dysphoric disorder
Authors: Ko Chih‐Hung , Long Cheng‐Yu , Yen Cheng‐Fang , Chen Cheng‐Sheng , Wang Peng‐Wei , Yen Ju‐Yu
Published: April 2014

Aim

Behavior inhibition and behavior approach system (BIS/BAS) determine the sensitivity to aversion and rewarding stimuli, respectively. This study aimed at evaluating the BIS/BAS of premenstrual dysphoric disorder (PMDD) and effect of estrogen and progesterone on the BIS/BAS.

Methods

Women with PMDD without treatment and control subjects were recruited from the community. The PMDD diagnosis was based on psychiatric interviewing and the result of two‐menstrual‐cycle follow up. A total of 67 women with PMDD and 75 control subjects were recruited and entered the final analysis. They were evaluated with BIS/BAS scale and for estrogen and progesterone levels in both premenstrual and follicular phases.

Results

The results revealed that BAS score was higher among women with PMDD in both premenstrual and follicular phases. Progesterone level negatively correlated with fun‐seeking, and its change in the menstrual cycle also negatively correlated to a change in fun‐seeking score among women with PMDD. Women with PMDD had a higher score in BIS in the premenstrual phase and the BIS score correlated to depression, anxiety, and hostility among them.

Conclusion

These results suggest reward sensitivity of women with PMDD is vulnerable to the effect of progesterone change in the menstrual cycle. Furthermore, the sensitivity to aversive stimuli plays an important role involving core symptoms of PMDD. The reinforcement sensitivity of PMDD deserves further detailed study.
Opposite variations in fumarate and malate dominate metabolic phenotypes of Arabidopsis salicylate mutants with abnormal biomass under chilling
Authors: Scott Ian M. , Ward Jane L. , Miller Sonia J. , Beale Michael H.
Published: April 2014

In chilling conditions (5°C), salicylic acid (SA)‐deficient mutants (sid2, eds5 and NahG) of Arabidopsis thaliana produced more biomass than wild type (Col‐0), whereas the SA overproducer cpr1 was extremely stunted. The hypothesis that these phenotypes were reflected in metabolism was explored using 600 MHz 1H nuclear magnetic resonance (NMR) analysis of unfractionated polar shoot extracts. Biomass‐related metabolic phenotypes were identified as multivariate data models of these NMR ‘fingerprints’. These included principal components that correlated with biomass. Also, partial least squares‐regression models were found to predict the relative size of plants in previously unseen experiments in different light intensities, or relative size of one genotype from the others. The dominant signal in these models was fumarate, which was high in SA‐deficient mutants, intermediate in Col‐0 and low in cpr1 at 5°C. Among signals negatively correlated with biomass, malate was prominent. Abundance of transcripts of the FUM2 cytosolic fumarase (At5g50950) showed strong positive correlation with fumarate levels and with biomass, whereas no significant differences were found for the FUM1 mitochondrial fumarase (At2g47510). It was confirmed that the morphological effects of SA under chilling find expression in the metabolome, with a role of fumarate highlighted.
Nutrient variability in phloem: examining changes in K, Mg, Zn and Fe concentration during grain loading in common wheat (Triticum aestivum)
Authors: Palmer Lachlan J. , Palmer Lyndon T. , Rutzke Michael A. , Graham Robin D. , Stangoulis James C. R.
Published: April 2014

In wheat, nutrients are transported to seeds via the phloem yet access to this vascular tissue for exudate collection and quantitative analysis of elemental composition is difficult. The purest phloem is collected through the use of aphid stylectomy with volumes of exudate collected normally in the range of 20–500 nl. In this work a new method using inductively coupled plasma mass spectroscopy (ICP‐MS) was developed to measure the concentration of K, Mg, Zn and Fe in volumes of wheat (Triticum aestivum, genotype Samnyt 16) phloem as small as 15.5 nl. This improved method was used to observe changes in phloem nutrient concentration during the grain loading period. There were statistically significant increases in phloem Mg and Zn concentration and a significant decrease in K over the period from 1–2 days after anthesis (DAA) to 9–12 DAA. During this period, there was no statistically significant change in phloem Fe concentration.
Photoperiodic regulation of receptacle induction in Sargassum horneri (Phaeophyceae) using clonal thalli
Authors: Yoshikawa Shinya , Kamiya Mitsunobu , Ohki Kaori
Published: April 2014

We developed a clonal culture of Sargassum horneri to investigate the effect of photoperiod on reproduction in this species. Regenerated vegetative thalli were obtained using lateral branches excised from a thallus grown from a single embryo under short‐day conditions (SD = 10:14 h light : dark cycle). Lateral branches excised from the SD‐regenerated thallus became vegetative thalli that remained in that phase as long as they were cultured under SD. When an excised lateral branch was cultured under long‐day conditions (LD = 14:10 h light : dark cycle), it began to enter the reproductive phase while still less than 50 mm long. Induction of the reproductive phase was accompanied by a distinctive morphological change – suppression of blade formation at the apical region of the branch; elongation of branches without blades was then followed by differentiation of receptacles bearing conceptacles on their surface. Apices of receptacles were able to interconvert between reproductive and vegetative phases, as blades resprouted upon transfer from LD to SD. The critical day length for induction of receptacle formation was between 13 and 14 h; receptacle formation was also induced under SD conditions with night breaks (NBs). These results strongly suggest that reproductive regulation of S. horneri is a photoperiodic long‐day response. NBs with blue and green light were effective for reproductive induction but not with red light. This suggests that blue‐ and/or green‐light photoreceptors are involved in the photoperiodic reproductive response of S. horneri.
Effect of irradiance and temperature on the photosynthesis of a cultivated red alga, Pyropia tenera (= Porphyra tenera), at the southern limit of distribution in Japan
Authors: Watanabe Yuki , Nishihara Gregory N. , Tokunaga Shigemitsu , Terada Ryuta
Published: April 2014

The effect of irradiance and temperature on the photosynthesis of the red alga, Pyropia tenera, was determined for maricultured gametophytes and sporophytes collected from a region that is known as one of the southern limits of its distribution in Japan. Macroscopic gametophytes were examined using both pulse‐amplitude modulated fluorometry and/or dissolved oxygen sensors. A model of the net photosynthesis–irradiance (P‐E) relationship of the gametophytes at 12°C revealed that the net photosynthetic rate quickly increased at irradiances below the estimated saturation irradiance of 46 μmol photons m−2 s−1, and the compensation irradiance was 9 μmol photons m−2 s−1. Gross photosynthesis and dark respiration for the gametophytes were also determined over a range of temperatures (8–34°C), revealing that the gross photosynthetic rates of 46.3 μmol O2 mgchl‐a−1 min−1 was highest at 9.3 (95% Bayesian credible interval (BCI): 2.3–14.5)°C, and the dark respiration rate increased at a rate of 0.93 μmol O2 mgchl‐a−1 min−1°C−1. The measured dark respiration rates ranged from −0.06 μmol O2 mgchl‐a−1 min−1 at 6°C to −25.2 μmol O2 mgchl‐a−1 min−1 at 34°C. The highest value of the maximum quantum yield (Fv/Fm) for the gametophytes occurred at 22.4 (BCI: 21.5–23.3) °C and was 0.48 (BCI: 0.475–0.486), although those of the sporophyte occurred at 12.9 (BCI: 7.4–15.1) °C and was 0.52 (BCI: 0.506–0.544). This species may be considered well‐adapted to the current range of seawater temperatures in this region. However, since the gametophytes have such a low temperature requirement, they are most likely close to their tolerable temperatures in the natural environment.
The Protection of Freshwater Ecosystems Revisited: Towards a Common Understanding of the ‘Ecosystems Approach’ to the Protection of Transboundary Water Resources
Authors: McIntyre Owen
Published: April 2014

The possible implications of States adopting, or of general international law imposing, a meaningful ‘ecosystems approach’ to the protection and management of shared international water resources are far‐reaching. However, the constituent elements of an ecosystems approach, as well as the practical means for its implementation, continue to emerge, though they have become increasingly well understood in recent years. Following the publication of an article ten years ago in RECIEL, this brief article sets out to update the reader on a number of key developments over the last ten years including, in particular: the proliferation of technical guidance on implementation of an ecosystems approach; recent focus on the need to safeguard ecological flows and the development of related methodologies; the emergence of the ecosystem services concept in international law and policy discourse; and the innovative employment of various ecosystem‐oriented measures in national legislative frameworks in recent years.
A Model for African Shared Water Resources: The Senegal River Legal System
Authors: Mbengue Makane Moïse
Published: April 2014

Twenty‐five years ago, the late B.A. Godana stressed that despite the gap between, on the one hand, the vast number of African international drainage basins and their potential for socio‐economic development of the States and, on the other hand, the dearth of international regulations governing water resources, it was noteworthy that the achievements in terms of cooperation were impressive. More than any other African river, the Senegal has been characterized and governed by the most progressive and articulated legal regime. The leitmotif since the inception of this legal regime has been to engage in an experiment that not only follows the most advanced concepts of integrated water resources management, but may also offer lessons in cooperation at the global level. Therefore, the legal architecture to foster cooperation over the management of the Senegal has influenced the development of the law of international watercourses in Africa.
Surgical treatment of mammary carcinomas in dogs with or without postoperative chemotherapy
Authors: Tran C. M. , Moore A. S. , Frimberger A. E.
Published: April 2014

This retrospective study identified prognostic factors associated with survival; and compared survival data in 94 canine mammary carcinoma (MCA) dogs treated with surgery (n= 58), or surgery and adjunct chemotherapy (n= 36), and a subset of dogs with poor prognostic factors. On multivariate analysis independent predictors of median survival time (MST) were clinical stage, lymphatic invasion (LI; present 179 days; none 1098 days), ulceration (present 118 days; none 443 days) and surgical margins (incomplete 70 days; complete 872 days). Complete surgical margins were associated with MST in dogs with stages 1–3 MCA (incomplete 68 days; complete 1098 days) and dogs with LI (incomplete 70 days; complete 347 days). There was no statistically significant improvement in MST in dogs with advanced disease (stage 4 or LI) treated with adjunctive chemotherapy (chemotherapy 228 days; none 194 days); although five dogs with complete surgical margins that received mitoxantrone and carboplatin had a mean survival of 1139 days.
A comparison of the clinical utility of several published formulae for estimated osmolality of canine serum
Authors: Dugger Daniel T. , Epstein Steven E. , Hopper Kate , Mellema Matthew S.
Published: April 2014

Objective

To determine the normal osmole gap for 18 previously published formulae used to estimate serum osmolality in dogs.

Design

Prospective study.

Setting

University veterinary medical teaching hospital.

Animals

Two hundred and fifty client‐owned dogs.

Interventions

None.

Measurements and Main Results

Serum samples were saved and frozen at −80°C after routine biochemical analysis as ordered by attending clinicians. An Advanced Micro Osmometer 3300 was used to measure serum osmolality. Eighteen distinct formulae previously reported in the medical literature were used to calculate the osmolality from the biochemical analysis results. The calculated osmolality was then subtracted from the measured osmolality to determine the osmole gap. Osmole gaps for azotemic and hyperglycemic dogs were compared to those of dogs without azotemia or hyperglycemia using each formula. The median measured osmolality for all dogs in the study was 302 mOsm/kg (interquartile range 297–307). The osmole gaps varied widely depending on the formula used to calculate osmolality and the presence or absence of hyperglycemia or azotemia. Eleven formulae led to calculated osmolality and osmole gaps that were not statistically different when hyperglycemia or azotemia was present. Four out of these 11 formulae resulted in osmole gaps near zero.

Conclusions and Clinical Relevance

Multiple formulae reported to calculate serum osmolality can be used in the clinical setting, but they result in significantly different normal osmole gaps. Clinicians should be aware of the specific reference interval for the formula being used. The authors recommend the formula 2(Na+) + [glucose/18] + [BUN/2.8] because it is easy to use and is reliable even when hyperglycemia or azotemia are present.
Prevalence and formation of primary cataracts and persistent hyperplastic tunica vasculosa lentis in the German Pinscher population in Germany
Authors: Pfahler Sophia , Menzel Julia , Brahm Rolf , Rosenhagen Carsten U. , Hafemeister Birgit , Schmidt Uta , Sinzinger Wolfgang , Distl Ottmar
Published: April 2014

Objective

The objective of this study was to describe the prevalences of primary noncongenital cataracts (CAT) and persistent hyperplastic tunica vasculosa lentis (PHTVL) in the German Pinscher population in Germany and to analyze the mode of inheritance of CAT in this dog breed.

Animals studied

All German Pinschers with a certified veterinary ophthalmological diagnosis and born between 1993 and 2010 were included in this study. Examinations were performed between 1997 and 2013 by certified veterinary ophthalmologists of the German panel of the European Eye Scheme for Diagnosis of Inherited Eye Diseases in Animals (DOK).

Procedures

Data were reviewed retrospectively for the prevalence of PHTVL, and the prevalence, location and age at diagnosis of CAT. Inheritance of CAT was analyzed using the Singles Method.

Results

A total of 779 eye examination reports of 409 dogs were available. Primary noncongenital cataracts were diagnosed in 64 (15.6%), and PHTVL in 13 (3.2%) of the examined dogs. The pedigrees included 168 ophthalmologically examined dogs with 104 CAT‐unaffected and 64 CAT‐affected dogs. All affected animals were offspring of a frequently used stud‐dog or closely related ancestors of this stud‐dog. Simple segregation analysis revealed a recessive mode of inheritance for CAT.

Conclusions

An early onset form of CAT with various cortical, posterior polar or multiple locations was the most prevalent manifestation among close relatives in German Pinschers. The pedigree analysis indicated a hereditary component of cataract formation with a monogenic autosomal recessive pattern of inheritance.
Human Pathogens in Marine Mammal Meat – A Northern Perspective
Authors: Tryland M. , Nesbakken T. , Robertson L. , Grahek‐Ogden D. , Lunestad B. T.
Published: April 2014

Only a few countries worldwide hunt seals and whales commercially. In Norway, hooded and harp seals and minke whales are commercially harvested, and coastal seals (harbour and grey seals) are hunted as game. Marine mammal meat is sold to the public and thus included in general microbiological meat control regulations. Slaughtering and dressing of marine mammals are performed in the open air on deck, and many factors on board sealing or whaling vessels may affect meat quality, such as the ice used for cooling whale meat and the seawater used for cleaning, storage of whale meat in the open air until ambient temperature is reached, and the hygienic conditions of equipment, decks, and other surfaces. Based on existing reports, it appears that meat of seal and whale does not usually represent a microbiological hazard to consumers in Norway, because human disease has not been associated with consumption of such foods. However, as hygienic control on marine mammal meat is ad hoc, mainly based on spot‐testing, and addresses very few human pathogens, this conclusion may be premature. Additionally, few data from surveys or systematic quality control screenings have been published. This review examines the occurrence of potential human pathogens in marine mammals, as well as critical points for contamination of meat during the slaughter, dressing, cooling, storage and processing of meat. Some zoonotic agents are of particular relevance as foodborne pathogens, such as Trichinella spp., Toxoplasma gondii, Salmonella and Leptospira spp. In addition, Mycoplasma spp. parapoxvirus and Mycobacterium spp. constitute occupational risks during handling of marine mammals and marine mammal products. Adequate training in hygienic procedures is necessary to minimize the risk of contamination on board, and acquiring further data is essential for obtaining a realistic assessment of the microbiological risk to humans from consuming marine mammal meat.
Numerical Detection of Stochastic to Deterministic Transition
Authors: Brojen Singh R. K.
Published: April 2014

We present the numerical estimation of noise parameter induced in the dynamics of the variables by random particle interactions involved in the stochastic chemical oscillator and use it as order parameter to detect the transition from stochastic to deterministic regime. In stochastic regime, this noise parameter is found to be increased as system size decreases, whereas in deterministic regime it remains constant to minimum value as system size increases. This let the transition from fluctuating to fixed limit cycle oscillation as the system goes from stochastic to deterministic transition. We also numerically estimated the strength of the noise parameter involved both in chemical Langevin equation and Master equation formalisms and found that strength of this parameter is much smaller in the former than the latter.
Large Eddy Simulation of Vaporizing Sprays Considering Multi-Injection Averaging and Grid-Convergent Mesh Resolution
Authors: Senecal P. K. , Pomraning E. , Xue Q. , Som S. , Banerjee S. , Hu B. , Liu K. , Deur J. M.
Published: April 2014

A state-of-the-art spray modeling methodology, recently presented by Senecal et al. (2012, “Grid Convergent Spray Models for Internal Combustion Engine CFD Simulations,” Proceedings of the ASME 2012 Internal Combustion Engine Division Fall Technical Conference, Vancouver, Canada, Paper No. ICEF2012-92043; 2013 “An Investigation of Grid Convergence for Spray Simulations using an LES Turbulence Model,” Paper No. SAE 2013-01-1083) is applied to large eddy simulations (LES) of vaporizing sprays. Simulations of noncombusting Spray A (n-dodecane fuel) from the engine combustion network are performed. An adaptive mesh refinement (AMR) cell size of 0.0625 mm is utilized based on the accuracy/runtime tradeoff demonstrated by Senecal et al. (2013, “An Investigation of Grid Convergence for Spray Simulations using an LES Turbulence Model,” Paper No. SAE 2013-01-1083). In that work, it was shown that grid convergence of key parameters for nonevaporating and evaporating sprays was achieved for cell sizes between 0.0625 and 0.125 mm using the dynamic structure LES model. The current work presents an extended and more thorough investigation of Spray A using multidimensional spray modeling and the dynamic structure LES model. Twenty different realizations are simulated by changing the random number seed used in the spray submodels. Multirealization (ensemble) averaging is shown to be necessary when comparing to local spray measurements of quantities such as mixture fraction and gas-phase velocity. Through a detailed analysis, recommendations are made regarding the minimum number of LES realizations required for accurate prediction of diesel sprays. Finally, the effect of a spray primary breakup model constant on the results is assessed.
Discussion: “A Simple Switching Control for Linear Systems to Assure Nonovershooting Step Responses” (Zhu, B., and Cai, K. Y., 2012, ASME J. Dyn. Syst. Meas., Control, 134, p. 034503)
Authors: Schmid Robert
Published: April 2014

This paper offers some comments on the article by Zhu and Cai (2012, “A Simple Switching Control for Linear Systems to Assure Nonovershooting Step Responses,” ASME J. Dyn. Syst. Meas., Control, 134, p. 034503). The authors offered a nonlinear switching scheme to obtain a nonovershooting step response from a linear plant, and motivated their method by showing that no linear Proportional-Integral-Derivative (PID) controller could achieve a nonovershooting response for a plant in the form of a triple integrator. In this paper, we show via an example that a linear state feedback controller in conjunction with a Luenberger observer can be found to achieve a nonovershooting response for a triple integrator.
Theory of graphene–insulator–graphene tunnel junctions
Authors: de la Barrera Sergio C. , Gao Qin , Feenstra Randall M.
Published: April 2014

Graphene–insulator–graphene vertical tunneling structures are discussed from a theoretical perspective. Momentum conservation in such devices leads to highly nonlinear current–voltage characteristics, which with gates on the tunnel junction form potentially useful transistor structures. Two prior theoretical treatments of such devices are discussed; the treatments are shown to be formally equivalent, although some differences in their implementations are identified. The limit of zero momentum conservation in the theory is explicitly considered, with a formula involving the density-of-states of the graphene electrodes recovered in this limit. Various predictions of the theory are compared to experiment.
Manufacturing Challenges in Regenerative Medicine
Authors: Martin Ivan , Simmons Paul J. , Williams David F.
Published: April 2014

Along with scientific and regulatory issues, the translation of cell and tissue therapies in the routine clinical practice needs to address standardization and cost-effectiveness through the definition of suitable manufacturing paradigms.
Active Skepticism: Beyond the IOM’s CTSA Report
Authors: Shekhar Anantha
Published: April 2014

U.S. national networks must set achievable modest goals and match them with reasonable resources in order to facilitate translational medicine projects.
Draft Genome Sequence of Quorum-Sensing and Quorum-Quenching Pseudomonas aeruginosa Strain MW3a
Authors: Chan Kok-Gan , Wong Cheng Siang , Yin Wai-Fong , Chan Xin Yue
Published: April 2014

Pseudomonas aeruginosa
has a broad range of habitation, from aquatic environments to human lungs. The coexistence of quorum-sensing and quorum-quenching activities occurs in
P. aeruginosa
strain MW3a. In this work, we present the draft genome sequence of
P. aeruginosa
MW3a, an interesting bacterium isolated from a marine environment.
Burkholderia pseudomallei Penetrates the Brain via Destruction of the Olfactory and Trigeminal Nerves: Implications for the Pathogenesis of Neurological Melioidosis
Authors: St. John James A. , Ekberg Jenny A. K. , Dando Samantha J. , Meedeniya Adrian C. B. , Horton Rachel E. , Batzloff Michael , Owen Suzzanne J. , Holt Stephanie , Peak Ian R. , Ulett Glen C. , Mackay-Sim Alan , Beacham Ifor R.
Published: April 2014

Melioidosis is a potentially fatal disease that is endemic to tropical northern Australia and Southeast Asia, with a mortality rate of 14 to 50%. The bacterium
Burkholderia pseudomallei
is the causative agent which infects numerous parts of the human body, including the brain, which results in the neurological manifestation of melioidosis. The olfactory nerve constitutes a direct conduit from the nasal cavity into the brain, and we have previously reported that
B. pseudomallei
can colonize this nerve in mice. We have now investigated in detail the mechanism by which the bacteria penetrate the olfactory and trigeminal nerves within the nasal cavity and infect the brain. We found that the olfactory epithelium responded to intranasal
B. pseudomallei
infection by widespread crenellation followed by disintegration of the neuronal layer to expose the underlying basal layer, which the bacteria then colonized. With the loss of the neuronal cell bodies, olfactory axons also degenerated, and the bacteria then migrated through the now-open conduit of the olfactory nerves. Using immunohistochemistry, we demonstrated that
B. pseudomallei
migrated through the cribriform plate via the olfactory nerves to enter the outer layer of the olfactory bulb in the brain within 24 h. We also found that the bacteria colonized the thin respiratory epithelium in the nasal cavity and then rapidly migrated along the underlying trigeminal nerve to penetrate the cranial cavity. These results demonstrate that
B. pseudomallei
invasion of the nerves of the nasal cavity leads to direct infection of the brain and bypasses the blood-brain barrier.

IMPORTANCE
Melioidosis is a potentially fatal tropical disease that is endemic to northern Australia and Southeast Asia. It is caused by the bacterium
Burkholderia pseudomallei
, which can infect many organs of the body, including the brain, and results in neurological symptoms. The pathway by which the bacteria can penetrate the brain is unknown, and we have investigated the ability of the bacteria to migrate along nerves that innervate the nasal cavity and enter the frontal region of the brain by using a mouse model of infection. By generating a mutant strain of
B. pseudomallei
which is unable to survive in the blood, we show that the bacteria rapidly penetrate the cranial cavity using the olfactory (smell) nerve and the trigeminal (sensory) nerve that line the nasal cavity.
O
-Mannosylation in Candida albicans Enables Development of Interkingdom Biofilm Communities
Authors: Dutton Lindsay C. , Nobbs Angela H. , Jepson Katy , Jepson Mark A. , Vickerman M. Margaret , Aqeel Alawfi Sami , Munro Carol A. , Lamont Richard J. , Jenkinson Howard F.
Published: April 2014

Candida albicans
is a fungus that colonizes oral cavity surfaces, the gut, and the genital tract.
Streptococcus gordonii
is a ubiquitous oral bacterium that has been shown to form biofilm communities with
C. albicans
. Formation of dual-species
S. gordonii
-
C. albicans
biofilm communities involves interaction of the
S. gordonii
SspB protein with the Als3 protein on the hyphal filament surface of
C. albicans
. Mannoproteins comprise a major component of the
C. albicans
cell wall, and in this study we sought to determine if mannosylation in cell wall biogenesis of
C. albicans
was necessary for hyphal adhesin functions associated with interkingdom biofilm development. A
C. albicans mnt1
Δ
mnt2
Δ mutant, with deleted α-1,2-mannosyltransferase genes and thus defective in
O
-mannosylation, was abrogated in biofilm formation under various growth conditions and produced hyphal filaments that were not recognized by
S. gordonii
. Cell wall proteomes of hypha-forming
mnt1
Δ
mnt2
Δ mutant cells showed growth medium-dependent alterations, compared to findings for the wild type, in a range of protein components, including Als1, Als3, Rbt1, Scw1, and Sap9. Hyphal filaments formed by
mnt1
Δ
mnt2
Δ mutant cells, unlike wild-type hyphae, did not interact with
C. albicans
Als3 or Hwp1 partner cell wall proteins or with
S. gordonii
SspB partner adhesin, suggesting defective functionality of adhesins on the
mnt1
Δ
mnt2
Δ mutant. These observations imply that early stage
O
-mannosylation is critical for activation of hyphal adhesin functions required for biofilm formation, recognition by bacteria such as
S. gordonii
, and microbial community development.

IMPORTANCE
In the human mouth, microorganisms form communities known as biofilms that adhere to the surfaces present.
Candida albicans
is a fungus that is often found within these biofilms. We have focused on the mechanisms by which
C. albicans
becomes incorporated into communities containing bacteria, such as
Streptococcus
. We find that impairment of early stage addition of mannose sugars to
C. albicans
hyphal filament proteins deleteriously affects their subsequent performance in mediating formation of polymicrobial biofilms. Our analyses provide new understanding of the way that microbial communities develop, and of potential means to control
C. albicans
infections.
Do rapid BMI growth in childhood and early-onset obesity offer cardiometabolic protection to obese adults in mid-life? Analysis of a longitudinal cohort study of Danish men
Authors: Howe Laura D , Zimmermann Esther , Weiss Ram , Sørensen Thorkild I A
Published: April 2014

Objective

Some obese individuals have no cardiometabolic abnormalities; they are ‘metabolically healthy, but obese’ (MHO). Similarly, some non-obese individuals have cardiometabolic abnormalities, that is, ‘metabolically at risk, normal weight’ (MANW). Previous studies have suggested that early-onset obesity may be associated with MHO. We aimed to assess whether body mass index (BMI) in childhood and early-onset obesity are associated with MHO.

Setting

General population longitudinal cohort study, Denmark.

Participants

From 362 200 young men (mean age 20) examined for Danish national service between 1943 and 1977, all obese men (BMI ≥31 kg/m2, N=1930) were identified along with a random 1% sample of the others (N=3601). Our analysis includes 2392 of these men attending a research clinic in mid-life (mean age 42). For 613 of these men, data on childhood BMI are available. We summarised childhood BMI growth (7–13 years) using a multilevel model. Early-onset obesity was defined as obesity at examination for national service.

Outcome measurement

We defined metabolic health at the mid-life clinic as non-fasting serum cholesterol <6.6 mmol/L, non-fasting glucose <8.39 mmol/L and pulse pressure <48 mm Hg. Participants were categorised into four groups according to their obesity (BMI ≥30 kg/m2) and metabolic health in mid-life.

Results

297 of 1097 (27.1%) of obese men were metabolically healthy; 826 of 1295 (63.8%) non-obese men had at least one metabolic abnormality. There was no evidence that rapid BMI growth in childhood or early-onset obesity was associated with either MHO or the MANW phenotype, for example, among obese men in mid-life, the OR for MHO comparing early-onset obesity with non-early-onset obesity was 0.97 (95% CI 0.85 to 1.10).

Conclusions

We found no robust evidence that early-onset obesity or rapid BMI growth in childhood is protective for cardiometabolic health.
A randomised controlled trial of an intervention to facilitate the implementation of healthy eating and physical activity policies and practices in childcare services
Authors: Jones Jannah , Wolfenden Luke , Wyse Rebecca , Finch Meghan , Yoong Sze Lin , Dodds Pennie , Pond Nicole , Gillham Karen , Freund Megan , McElduff Patrick , Wye Paula , Wiggers John
Published: April 2014

Introduction

Childhood overweight and obesity tracks into adulthood, increasing the risk of developing future chronic disease. Implementing initiatives promoting healthy eating and physical activity in childcare settings has been identified as a priority to prevent excessive child weight gain. Despite this, few trials have been conducted to assess the effectiveness of interventions to support population-wide implementation of such initiatives. The aim of this study is to assess the effectiveness of a multicomponent intervention in increasing the implementation of healthy eating and physical activity policies and practices by centre-based childcare services.

Methods and analysis

The study will employ a parallel group randomised controlled trial design. A sample of 128 childcare services in the Hunter region of New South Wales, Australia, will be recruited to participate in the trial. 64 services will be randomly allocated to a 12-month implementation intervention. The remaining 64 services will be allocated to a usual care control group. The intervention will consist of a number of strategies to facilitate childcare service implementation of healthy eating and physical activity policies and practices. Intervention strategies will include implementation support staff, securing executive support, consensus processes, staff training, academic detailing visits, performance monitoring and feedback, tools and resources, and a communications strategy. The primary outcome of the trial will be the prevalence of services implementing all healthy eating and physical activity policies and practices targeted by the intervention. To assess the effectiveness of the intervention, telephone surveys with nominated supervisors and room leaders of childcare services will be conducted at baseline and immediately postintervention.

Ethics and dissemination

The study was approved by the Hunter New England Human Research Ethics Committee and the University of Newcastle Human Research Ethics Committee. Study findings will be disseminated widely through peer-reviewed publications and conference presentations.

Trial registration number

Australian Clinical Trials Registry ACTRN12612000927820.
Nitrous oxide use during colonoscopy: a national survey of English screening colonoscopists
Authors: Ball Alex J , Campbell Jennifer A , Riley Stuart A
Published: April 2014

Introduction

Nitrous oxide can improve patient experience during colonoscopy, and its rapid elimination minimises after effects and inconvenience. Despite its advantages, nitrous oxide is used infrequently in the UK. We sought to understand the reasons for its low use.

Methods

Colonoscopists within the English Bowel Cancer Screening Programme (BCSP) were invited to participate in a web-based survey assessing the availability, current practices and perceptions towards nitrous oxide. Respondents were able to select predefined answers or offer written responses. Free text responses were assessed using thematic analysis.

Results

The survey was completed by 68% of the English BCSP colonoscopists. Nitrous oxide was available to 73% of respondents but with considerable regional variation. Most colonoscopists rated the properties of nitrous oxide favourably and would use it if they had a colonoscopy themselves. Despite this, nearly half used it in less than 20% of examinations. 80% instruct patients to use nitrous oxide as required, and differences in how it was used in combination with intravenous sedation and analgesia were reported. Written responses suggest nitrous oxide is often used in the patients who are expected to have the least discomfort.

Conclusions

Most colonoscopists perceive that nitrous oxide is effective and reduces inconvenience and would use it themselves if they required a colonoscopy. Studies to improve patient selection and optimise the use of nitrous oxide would be of value.
High and low contraceptive use amongst young male offenders: a qualitative interview study
Authors: Buston Katie , Parkes Alison , Wight Danny
Published: April 2014

Objectives

There are high rates of fatherhood and sexually transmitted infections (STIs) among young incarcerated men. Here we focus on a sample of men incarcerated in a Scottish Young Offender Institution, analysing their accounts of their contraceptive use. Those who report low or no use of contraception are compared with those who report high use.

Methods

Semi-structured interviews with 40 young male offenders, aged 16–21 years. Participants were purposively sampled using answers from a questionnaire administered to 67 inmates. Data from those men (n=31) reporting either high (n=14) or low/no use (n=17) of contraception are analysed here.

Results

Low users emphasise their desire for pleasure and appear fatalistic about both pregnancy and disease prevention. High users report a strong desire to protect themselves and their ‘manliness’ by using condoms to avoid the risk of STIs and, to a lesser extent, pregnancy. Both sets of men present themselves in a traditionally masculine way, with high users emphasising power, authority and self-control to justify their non-risk-taking contraceptive behaviour.

Conclusions

The masculine narrative regarding self-protection, utilised by the high users, may be an effective method of intervention with potential and actual low users. Conventional masculinity valorises risk-taking but if particular forms of risk avoidance – condom use – can be legitimised as confirming one's masculinity it may be possible to persuade low users to adopt them. The opportunity to work with young men whilst incarcerated should be grasped.
Modeling nuclear resonance vibrational spectroscopic data of binuclear nonheme iron enzymes using density functional theory
Authors: Park Kiyoung , Solomon Edward I.
Published: April 2014

Nuclear resonance vibrational spectroscopy (NRVS) is a powerful technique that can provide geometric structural information on key reaction intermediates of Fe-containing systems when utilized in combination with density functional theory (DFT). However, in the case of binuclear nonheme iron enzymes, DFT-predicted NRVS spectra have been found to be sensitive to the truncation method used to model the active sites of the enzymes. Therefore, in this study various-level truncation schemes have been tested to predict the NRVS spectrum of a binuclear nonheme iron enzyme, and a reasonably sized DFT model that is suitable for employing the NRVS/DFT combined methodology to characterize binuclear nonheme iron enzymes has been developed.
Validation experiments for LBM simulations of electron beam melting
Authors: Ammer Regina , Rüde Ulrich , Markl Matthias , Jüchter Vera , Körner Carolin
Published: April 2014

This paper validates three-dimensional (3D) simulation results of electron beam melting (EBM) processes by comparing experimental and numerical data. The physical setup is presented which is discretized by a 3D thermal lattice Boltzmann method (LBM). An experimental process window is used for the validation depending on the line energy injected into the metal powder bed and the scan velocity of the electron beam. In the process window, the EBM products are classified into the categories, porous, good and swelling, depending on the quality of the surface. The same parameter sets are used to generate a numerical process window. A comparison of numerical and experimental process windows shows a good agreement. This validates the EBM model and justifies simulations for future improvements of the EBM processes. In particular, numerical simulations can be used to explain future process window scenarios and find the best parameter set for a good surface quality and dense products.
The simplest models of radiative neutrino mass
Authors: Law Sandy S. C. , McDonald Kristian L.
Published: April 2014

The complexity of radiative neutrino-mass models can be judged by: (i) whether they require the imposition of ad hoc symmetries, (ii) the number of new multiplets they introduce and (iii) the number of arbitrary parameters that appear. Considering models that do not employ new symmetries, the simplest models have two new multiplets and a minimal number of new parameters. With this in mind, we search for the simplest models of radiative neutrino mass. We are led to two models, containing a real scalar triplet and a charged scalar doublet (respectively), in addition to the charged singlet scalar considered by Zee [h+~(1, 1, 2)]. These models are essentially simplified versions of the Zee model and appear to be the simplest models of radiative neutrino mass. However, despite successfully generating nonzero masses, present-day data is sufficient to rule these simple models out. The Zee and Zee–Babu models therefore remain as the simplest viable models. Moving beyond the minimal cases, we find a new model of two-loop masses that employs the charged doublet Φ~(1, 2, 3) and the doubly-charged scalar k++~(1, 1, 4). This is the sole remaining model that employs only three new noncolored multiplets.
A Semantic Framework for Harvesting Vague Enterprise Knowledge from Microposts
Authors: Alexopoulos Panos , Pavlopoulos John , Mylonas Phivos
Published: April 2014

The advent and wide proliferation of Social Web in the recent years has promoted the concept of social interaction as an important influencing factor of the way enterprises and organizations conduct business. Among the fields influenced is that of Enterprise Knowledge Management, where the increase and maintenance of the employees' active participation in the organization's knowledge management activities is pursued through the adoption of social computing approaches. In this paper we consider a prominent and increasingly applied such approach, namely enterprise microblogging, and we propose a novel way to exploit its knowledge generation and sharing capabilities in order to effectively capture and formalize enterprise knowledge that is vague. Application and empirical evaluation of the framework indicates significant potential towards this goal.
Two- and three-cocycles for Laver tables
Authors: Dehornoy Patrick , Lebed Victoria
Published: April 2014

We determine all 2- and 3-cocycles for Laver tables, an infinite sequence of finite structures obeying the left-self-distributivity law; in particular, we describe simple explicit bases. This provides a number of new positive braid invariants and paves the way for further potential topological applications. An important tool for constructing a combinatorially meaningful basis of 2-cocycles is the right-divisibility relation on Laver tables, which turns out to be a partial ordering.
Chalcogenide Brillouin lasers
Authors: Kabakova Irina V. , Pant Ravi , Winful Herbert G. , Eggleton Benjamin J.
Published: April 2014

In recent years, chalcogenide glasses have emerged as a material platform for nonlinear signal processing and mid-infrared photonics. In addition, high Brillouin gain of these soft glasses enable compact and highly efficient Brillouin lasers (BL). We review recent progress on chalcogenide BL, compare fiber and waveguide laser geometries, and discuss the potential of chalcogenide platform for compact and high-coherence light sources.
A generalized family of multidimensional continued fractions: TRIP Maps
Authors: Dasaratha Krishna , Flapan Laure , Garrity Thomas , Lee Chansoo , Mihaila Cornelia , Neumann-Chun Nicholas , Peluse Sarah , Stoffregen Matthew
Published: April 2014

Most well-known multidimensional continued fractions, including the Mönkemeyer map and the triangle map, are generated by repeatedly subdividing triangles. This paper constructs a family of multidimensional continued fractions by permuting the vertices of these triangles before and after each subdivision. We obtain an even larger class of multidimensional continued fractions by composing the maps in the family. These include the algorithms of Brun, Parry-Daniels and Güting. We give criteria for when multidimensional continued fractions associate sequences to unique points, which allows us to determine when periodicity of the corresponding multidimensional continued fraction corresponds to pairs of real numbers being cubic irrationals in the same number field.
Study on branching ratios and direct CP asymmetries of D → PV decays
Authors: Qin Qin , Li Hsiang-Nan , Lü Cai-Dian , Yu Fu-Sheng
Published: April 2014

We study the non-leptonic two-body decays of D mesons decaying into one pseudoscalar meson (P) and one vector meson (V) in the factorization-asisted topological-amplitude approach. In this approach, the decay amplitudes are factorized into two parts, the short-distance contribution (Wilson coefficients) and the long-distance contribution (hadronic matrix elements). We predict the branching ratios of D → PV decays using a global fit with the non-perturbative parameters. Our results agree well with the experimental data. We also predict the direct CP asymmetries by combining short-distance dynamics associated with penguin operators and long-distance hadronic matrix elements determined by branching ratios. The large asymmetries in D+ → π+ρ0 and [Formula: see text] may be measurable in the LHCb and future Belle II experiments.