bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular and physiological responses of trees to waterlogging stress
Authors: KREUZWIESER JÜRGEN , RENNENBERG HEINZ
Published: February 2014

One major effect of global climate change will be altered precipitation patterns in many regions of the world. This will cause a higher probability of long‐term waterlogging in winter/spring and flash floods in summer because of extreme rainfall events. Particularly, trees not adapted at their natural site to such waterlogging stress can be impaired. Despite the enormous economic, ecological and social importance of forest ecosystems, the effect of waterlogging on trees is far less understood than the effect on many crops or the model plantArabidopsis. There is only a handful of studies available investigating the transcriptome and metabolome of waterlogged trees. Main physiological responses of trees to waterlogging include the stimulation of fermentative pathways and an accelerated glycolytic flux. Many energy‐consuming, anabolic processes are slowed down to overcome the energy crisis mediated by waterlogging. A crucial feature of waterlogging tolerance is the steady supply of glycolysis with carbohydrates, particularly in the roots; stress‐sensitive trees fail to maintain sufficient carbohydrate availability resulting in the dieback of the stressed tissues. The present review summarizes physiological and molecular features of waterlogging tolerance of trees; the focus is on carbon metabolism in both, leaves and roots of trees.
Timing as a source of regulatory influence: A technical elite network analysis of global finance
Authors: Lall Ranjit
Published: February 2014

Rules governing the international financial system are the subject of some of the most intense distributional battles waged in any area of global governance. Who wins and who loses such battles – and why?Idevelop a novel analytical framework – technical elite network (TEN) theory – which explains the widely varying levels of influence that stakeholders enjoy over global financial standards.TENtheory draws attention to how issue‐specific characteristics of international finance – in particular, its highly technical and complex nature – shape the distributional consequences of global regulatory processes. It posits that such characteristics influence distributional outcomes by (i) affecting who claims first‐mover position and, thus, sets the agenda in global financial rulemaking, and (ii) ensuring that proposals made by first movers are increasingly difficult to alter at later stages of rulemaking. I provide empirical evidence for the theory by examining two regulatory regimes that are central to the efficiency and stability of the global financial system: theBaselCommittee onBankingSupervision and theInternationalAccountingStandardsBoard.
Sudden Stops and Currency Crashes
Authors: Zhao Yanping , de Haan Jakob , Scholtens Bert , Yang Haizhen
Published: February 2014

This paper investigates which factors determine whether sudden stops in international capital flows are followed by a currency crash using data for 85 economies in the period 1980–2012. An event study approach is used for an 11‐year window around the crises for nine potential explanatory variables. In addition, the paper estimates discrete‐choice panel models. The results suggest that low trade openness, shallow financial markets, and current account imbalances increase the likelihood that a sudden stop will be followed by a currency crash. Moreover, it is established that the impact of these factors differs across different exchange rate regimes.
The Arabidopsis Tellurite resistance C protein together with ALB3 is involved in photosystem II protein synthesis
Authors: Schneider Anja , Steinberger Iris , Strissel Henning , Kunz Hans‐Henning , Manavski Nikolay , Meurer Jörg , Burkhard Gabi , Jarzombski Sabine , Schünemann Danja , Geimer Stefan , Flügge Ulf‐Ingo , Leister Dario
Published: February 2014

Assembly of photosystem II (PSII) occurs sequentially and requires several auxiliary proteins, such as ALB3 (ALBINO3). Here, we describe the role of the Arabidopsis thaliana thylakoid membrane protein Tellurite resistance C (AtTerC) in this process. Knockout of AtTerC was previously shown to be seedling‐lethal. This phenotype was rescued by expressing TerC fused C–terminally to GFP in the terc–1 background, and the resulting terc–1TerC–GFP line and an artificial miRNA‐based knockdown allele (amiR‐TerC) were used to analyze the TerC function. The alterations in chlorophyll fluorescence and thylakoid ultrastructure observed in amiR‐TerC plants and terc–1TerC–GFP were attributed to defects in PSII. We show that this phenotype resulted from a reduction in the rate of de novo synthesis of PSII core proteins, but later steps in PSII biogenesis appeared to be less affected. Yeast two‐hybrid assays showed that TerC interacts with PSII proteins. In particular, its interaction with the PSII assembly factor ALB3 has been demonstrated by co‐immunoprecipitation. ALB3 is thought to assist in incorporation of CP43 into PSII via interaction with Low PSII Accumulation2 (LPA2) Low PSII Accumulation3 (LPA3). Homozygous lpa2 mutants expressing amiR‐TerC displayed markedly exacerbated phenotypes, leading to seedling lethality, indicating an additive effect. We propose a model in which TerC, together with ALB3, facilitates de novo synthesis of thylakoid membrane proteins, for instance CP43, at the membrane insertion step.
Strigolactones and the control of plant development: lessons from shoot branching
Authors: Waldie Tanya , McCulloch Hayley , Leyser Ottoline
Published: February 2014

Strigolactones (SLs) were originally identified through their activities as root exudates in the rhizosphere; however, it is now clear that they have many endogenous signalling roles in plants. In this review we discuss recent progress in understanding SL action in planta, particularly in the context of the regulation of shoot branching, one of the best‐characterized endogenous roles for SLs. Rapid progress has been made in understanding SL biosynthesis, but many questions remain unanswered. There are hints of as yet unidentified sources of SL, as well as unknown SL–like molecules with important signalling functions. SL signalling is even more enigmatic. Although a likely receptor has been identified, along with some candidate immediate downstream targets, our understanding of how these targets mediate SL signalling is limited. There is still considerable uncertainty about whether the targets of SL signalling are primarily transcriptional or not. There is at least one non‐transcriptional target, because a rapid primary response to SL is the removal of PIN1 auxin exporter proteins from the plasma membrane in vascular‐associated cells of the stem. We discuss how the various early events in SL signalling could result in the observed changes in shoot branching.
In vivo and in vitro biophysical properties of hair cells from the lateral line and inner ear of developing and adult zebrafish
Authors: Olt Jennifer , Johnson Stuart L. , Marcotti Walter
Published: February 2014

Key points

Sound and balance information is detected and processed by sensory hair cells in the auditory and vestibular organs, respectively.

The zebrafish represents a potentially powerful model organism in which to investigate sensory encoding by hair cells because of its accessibility for in vivo studies and its pliable genetics.

Our current understanding of hair cell biophysics in the developing zebrafish is very limited.

In this study, we used in vivo and near‐physiological in vitro recordings to measure basolateral membrane currents, voltage changes and synaptic activity in hair cells in the developing and mature zebrafish.

We found that the biophysical profile of lateral line hair cells in the zebrafish changes from the larval to the juvenile stage, and that juvenile neuromasts contain a much higher proportion of mature cells.

These results demonstrate the potential of the zebrafish for investigating the mechanisms of signal encoding and transmission by hair cells.

Hair cells detect and process sound and movement information, and transmit this with remarkable precision and efficiency to afferent neurons via specialized ribbon synapses. The zebrafish is emerging as a powerful model for genetic analysis of hair cell development and function both in vitro and in vivo. However, the full exploitation of the zebrafish is currently limited by the difficulty in obtaining systematic electrophysiological recordings from hair cells under physiological recording conditions. Thus, the biophysical properties of developing and adult zebrafish hair cells are largely unknown. We investigated potassium and calcium currents, voltage responses and synaptic activity in hair cells from the lateral line and inner ear in vivo and using near‐physiological in vitro recordings. We found that the basolateral current profile of hair cells from the lateral line becomes more segregated with age, and that cells positioned in the centre of the neuromast show more mature characteristics and those towards the edge retain a more immature phenotype. The proportion of mature‐like hair cells within a given neuromast increased with zebrafish development. Hair cells from the inner ear showed a developmental change in current profile between the juvenile and adult stages. In lateral line hair cells from juvenile zebrafish, exocytosis also became more efficient and required less calcium for vesicle fusion. In hair cells from mature zebrafish, the biophysical characteristics of ion channels and exocytosis resembled those of hair cells from other lower vertebrates and, to some extent, those in the immature mammalian vestibular and auditory systems. We show that although the zebrafish provides a suitable animal model for studies on hair cell physiology, it is advisable to consider that the age at which the majority of hair cells acquire a mature‐type configuration is reached only in the juvenile lateral line and in the inner ear from >2 months after hatching.
A Noncyclic Method for Determination of Accumulated Strain in Stainless Steel 304 Pressure Vessels
Authors: Jiang Gongfeng , Chen Gang , Sun Liang , Zhang Yiliang , Jia Xiaoliang , Liu Yinghua
Published: February 2014

Experimental results of uniaxial ratcheting tests for stainless steel 304 (SS304) under stress-controlled condition at room temperature showed that the elastic domain defined in this paper expands with accumulation of plastic strain. Both ratcheting strain and viscoplastic strain rates reduce with the increase of elastic domain, and the total strain will be saturated finally. If the saturated strain and corresponded peak stress of different experimental results under the stress ratio R ≥ 0 are plotted, a curve demonstrating the material shakedown states of SS304 can be constituted. Using this curve, the accumulated strain in a pressure vessel subjected to cyclic internal pressure can be determined by only an elastic-plastic analysis, and without the cycle-by-cycle analysis. Meanwhile, a physical experiment of a thin-walled pressure vessel subjected to cyclic internal pressure has been carried out to verify the feasibility and effectiveness of this noncyclic method. By comparison, the accumulated strains evaluated by the noncyclic method agreed well with those obtained from the experiments. The noncyclic method is simpler and more practical than the cycle-by-cycle method for engineering design.
Using Singularities of Parallel Manipulators to Enhance the Rigid-Body Replacement Design Method of Compliant Mechanisms
Authors: Rubbert Lennart , Caro Stéphane , Gangloff Jacques , Renaud Pierre
Published: February 2014

The rigid-body replacement method is often used when designing a compliant mechanism. The stiffness of the compliant mechanism, one of its main properties, is then highly dependent on the initial choice of a rigid-body architecture. In this paper, we propose to enhance the efficiency of the synthesis method by focusing on the architecture selection. This selection is done by considering the required mobilities and parallel manipulators in singularity to achieve them. Kinematic singularities of parallel structures are indeed advantageously used to propose compliant mechanisms with interesting stiffness properties. The approach is first illustrated by an example, the design of a one degree of freedom compliant architecture. Then, the method is used to design a medical device where a compliant mechanism with three degrees of freedom is needed. The interest of the approach is outlined after application of the method.
Computational Fluid Dynamics Simulations and Experiments for Reduction of Oil Churning Loss and Windage Loss in Aeroengine Transmission Gears
Authors: Arisawa Hidenori , Nishimura Motohiko , Imai Hideyuki , Goi Tatsuhiko
Published: February 2014

The demand for power generation capacity has increased considerably due to the electric drive of cabin air conditioners and commercial aircraft engines. It is estimated that power losses may increase in the accessory gearbox due to generators and pumps that augment fuel consumption. To reduce these losses, a computational fluid dynamics simulation technique that analyzes oil churning and windage losses was developed and improvements were made to the shrouds of bevel gears, which have large losses in the gearbox. It was revealed experimentally that shrouding reduced losses up to 36% as compared to unshrouded gears.
Two-Faced Viral Protein
Authors: Vinson Valda K.
Published: February 2014

The structure of a viral protein provides a basis for understanding its function and could guide vaccine development.
Engineering Tissue Repair
Authors: VanHook Annalisa M.
Published: February 2014

Small quantities of growth factors modified to have high affinity for the extracellular matrix stimulate tissue repair.
Hexokinase-II Integrates Glycolysis and Autophagy
Authors: Gough Nancy R.
Published: February 2014

Substrate inhibition of the glycolytic enzyme hexokinase-II promotes mTORC1-dependent autophagy in the heart.
Surviving DNA Damage Through Golgi Dispersal
Authors: Ferrarelli Leslie K.
Published: February 2014

DNA repair protein DNA-PK promotes cell survival after DNA damage by phosphorylating Golgi phosphoprotein GOLPH3.
Intrapulmonary Posaconazole Penetration at the Infection Site in an Immunosuppressed Murine Model of Invasive Pulmonary Aspergillosis Receiving Oral Prophylactic Regimens
Authors: Seyedmousavi Seyedmojtaba , Brüggemann Roger J. M. , Melchers Willem J. G. , Verweij Paul E. , Mouton Johan W.
Published: February 2014

Adequate penetration to the infection/colonization site is crucial to attain optimal efficacy of posaconazole against
Aspergillus fumigatus
diseases. We evaluated posaconazole exposure in pulmonary epithelial lining fluid (ELF) in a murine model of invasive pulmonary aspergillosis. The posaconazole exposure (area under the plasma concentration-time curve from time zero to 24 h postinfusion [AUC
0–24
]) in ELF was 20% to 31% of that in plasma for total drug after the third dose, and the relationship between plasma and ELF exposure was linear (
r
2
= 0.97,
P
= 0.016).
Pharmacokinetic and Safety Analyses of Tenofovir and Tenofovir-Emtricitabine Vaginal Tablets in Pigtailed Macaques
Authors: Pereira Lara E. , Clark Meredith R. , Friend David R. , Garber David A. , McNicholl Janet M. , Hendry R. Michael , Doncel Gustavo F. , Smith James M.
Published: February 2014

Vaginal rapidly disintegrating tablets (RDTs) containing tenofovir (TFV) or TFV and emtricitabine (FTC) were evaluated for safety and pharmacokinetics in pigtailed macaques. Two separate animal groups (n= 4) received TFV (10 mg) or TFV-FTC (10 mg each) RDTs, administered near the cervix. A third group (n= 4) received 1 ml TFV gel. Blood plasma, vaginal tissue biopsy specimens, and vaginal fluids were collected before and after product application at 0, 0.5, 1, 4, and 24 h. A disintegration time of <30 min following vaginal application of the RDTs was noted, with negligible effects on local inflammatory cytokines, vaginal pH, and microflora. TFV pharmacokinetics were generally similar for both RDTs and gel, with peak median concentrations in vaginal tissues and vaginal secretions being on the order of 104to 105ng/g (147 to 571 μM) and 106ng/g (12 to 34 mM), respectively, at 1 to 4 h postdose. At 24 h, however, TFV vaginal tissue levels were more sustained after RDT dosing, with median TFV concentrations being approximately 1 log higher than those with gel dosing. FTC pharmacokinetics after combination RDT dosing were similar to those of TFV, with peak median vaginal tissue and fluid levels being on the order of 104ng/g (374 μM) and 106ng/g (32 mM), respectively, at 1 h postdose with levels in fluid remaining high at 24 h. RDTs are a promising alternative vaginal dosage form, delivering TFV and/or FTC at levels that would be considered inhibitory to simian-human immunodeficiency virus in the macaque vaginal microenvironment over a 24-h period.
In Vitro
Assessment and Multicenter Cohort Study of Comparative Nephrotoxicity Rates Associated with Colistimethate versus Polymyxin B Therapy
Authors: Phe Kady , Lee Yuman , McDaneld Patrick M. , Prasad Nishant , Yin Taijun , Figueroa Deborah A. , Musick William L. , Cottreau Jessica M. , Hu Ming , Tam Vincent H.
Published: February 2014

Despite concerns of nephrotoxicity, polymyxin antibiotics often remain the only susceptible agents for multidrug-resistant (MDR) Gram-negative bacteria. Colistin has been more commonly used clinically due to a perceived safety benefit. We compared the nephrotoxicity of colistin to polymyxin B. The
in vitro
cytotoxicity of colistin was compared to polymyxin B in two mammalian renal cell lines. To validate the clinical relevance of the findings, we evaluated adult patients with normal renal function who received a minimum of 72 h of polymyxin therapy in a multicenter study. The primary outcome was the prevalence of nephrotoxicity, as defined by the RIFLE (risk, injury, failure, loss, end-stage kidney disease) criteria. Colistin exhibited an
in vitro
cytotoxicity profile similar to polymyxin B. A total of 225 patients (121 receiving colistimethate, 104 receiving polymyxin B) were evaluated. Independent risk factors for colistimethate-associated nephrotoxicity included age (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.00 to 1.07;
P
= 0.03), duration of therapy (OR 1.08; 95% CI, 1.02 to 1.15;
P
= 0.02), and daily dose by ideal body weight (OR 1.40; 95% CI, 1.05 to 1.88;
P
= 0.02). In contrast, cystic fibrosis was found to be a protective factor in patients who received colistimethate (OR, 0.03; 95% CI, 0.001 to 0.79;
P
= 0.04). In a matched analysis based on the risk factors identified (
n
= 76), the prevalence of nephrotoxicity was higher with colistimethate than with polymyxin B (55.3% versus 21.1%;
P
= 0.004). Polymyxin B was not found to be more nephrotoxic than colistin and may be the preferred polymyxin for MDR infections. A prospective study comparing the two polymyxins directly is warranted.
DhhP, a Cyclic di-AMP Phosphodiesterase of Borrelia burgdorferi, Is Essential for Cell Growth and Virulence
Authors: Ye Meiping , Zhang Jun-Jie , Fang Xin , Lawlis Gavin B. , Troxell Bryan , Zhou Yan , Gomelsky Mark , Lou Yongliang , Yang X. Frank
Published: February 2014

Cyclic di-AMP (c-di-AMP) is a recently discovered second messenger in bacteria. Most of work on c-di-AMP signaling has been done in Gram-positive bacteria, firmicutes, and actinobacteria, where c-di-AMP signaling pathways affect potassium transport, cell wall structure, and antibiotic resistance. Little is known about c-di-AMP signaling in other bacteria.Borrelia burgdorferi, the causative agent of Lyme disease, is a spirochete that has a Gram-negative dual membrane. In this study, we demonstrated thatB. burgdorferiBB0619, aDHH-DHHA1 domainprotein (herein designated DhhP), functions as c-di-AMP phosphodiesterase. Recombinant DhhP hydrolyzed c-di-AMP to pApA in a Mn2+- or Mg2+-dependent manner. In contrast to c-di-AMP phosphodiesterases reported thus far, DhhP appears to be essential forB. burgdorferigrowth bothin vitroand in the mammalian host. Inactivation of the chromosomaldhhPgene could be achieved only in the presence of a plasmid-encoded inducibledhhPgene. The conditionaldhhPmutant had a dramatic increase in intracellular c-di-AMP level in comparison to the isogenic wild-type strain. Unlike what has been observed in Gram-positive bacteria, elevated cellular c-di-AMP inB. burgdorferidid not result in an increased resistance to β-lactamase antibiotics, suggesting that c-di-AMP's functions in spirochetes differ from those in Gram-positive bacteria. In addition, thedhhPmutant was defective in induction of the σSfactor, RpoS, and the RpoS-dependent outer membrane virulence factor OspC, which uncovers an important role of c-di-AMP inB. burgdorferivirulence.
Attenuation of Intestinal Inflammation in Interleukin-10-Deficient Mice Infected with Citrobacter rodentium
Authors: Dann Sara M. , Le Christine , Choudhury Barun K. , Liu Houpu , Saldarriaga Omar , Hanson Elaine M. , Cong Yingzi , Eckmann Lars
Published: February 2014

Interleukin-10 (IL-10) curtails immune responses to microbial infection and autoantigens and contributes to intestinal immune homeostasis, yet administration of IL-10 has not been effective at attenuating chronic intestinal inflammatory conditions, suggesting that its immune functions may be context dependent. To gain a broader understanding of the importance of IL-10 in controlling mucosal immune responses to infectious challenges, we employed the murine attaching and effacing pathogenCitrobacter rodentium, which colonizes primarily the surfaces of the cecum and colon and causes transient mucosal inflammation driven by Th17 and Th1 T helper cells. Infection induced macrophage and dendritic cell production of IL-10, which diminished antibacterial host defenses, because IL-10-deficient mice cleared infection faster than wild-type controls. In parallel, the mice had less acute infection-associated colitis and resolved it more rapidly than controls. Importantly, transientC. rodentiuminfection protected IL-10-deficient mice against the later development of spontaneous colitis that normally occurs with aging in these mice. Genome-wide expression studies revealed that IL-10 deficiency was associated with downregulation of proinflammatory pathways but increased expression of the anti-inflammatory cytokine IL-27 in response to infection. IL-27 was found to suppressin vitroTh17 and, to a lesser degree, Th1 differentiation independent of IL-10. Furthermore, neutralization of IL-27 resulted in more severe colitis in infected IL-10-deficient mice. Together, these findings indicate that IL-10 is dispensable for resolvingC. rodentium-associated colitis and further suggest that IL-27 may be a critical factor for controlling intestinal inflammation and Th17 and Th1 development by IL-10-independent mechanisms.
Symbiotic Relationship between Streptococcus mutans and Candida albicans Synergizes Virulence of Plaque Biofilms
In Vivo
Authors: Falsetta Megan L. , Klein Marlise I. , Colonne Punsiri M. , Scott-Anne Kathleen , Gregoire Stacy , Pai Chia-Hua , Gonzalez-Begne Mireya , Watson Gene , Krysan Damian J. , Bowen William H. , Koo Hyun
Published: February 2014

Streptococcus mutans
is often cited as the main bacterial pathogen in dental caries, particularly in early-childhood caries (ECC).
S. mutans
may not act alone;
Candida albicans
cells are frequently detected along with heavy infection by
S. mutans
in plaque biofilms from ECC-affected children. It remains to be elucidated whether this association is involved in the enhancement of biofilm virulence. We showed that the ability of these organisms together to form biofilms is enhanced
in vitro
and
in vivo
. The presence of
C. albicans
augments the production of exopolysaccharides (EPS), such that cospecies biofilms accrue more biomass and harbor more viable
S. mutans
cells than single-species biofilms. The resulting 3-dimensional biofilm architecture displays sizeable
S. mutans
microcolonies surrounded by fungal cells, which are enmeshed in a dense EPS-rich matrix. Using a rodent model, we explored the implications of this cross-kingdom interaction for the pathogenesis of dental caries. Coinfected animals displayed higher levels of infection and microbial carriage within plaque biofilms than animals infected with either species alone. Furthermore, coinfection synergistically enhanced biofilm virulence, leading to aggressive onset of the disease with rampant carious lesions. Our
in vitro
data also revealed that glucosyltransferase-derived EPS is a key mediator of cospecies biofilm development and that coexistence with
C. albicans
induces the expression of virulence genes in
S. mutans
(e.g.,
gtfB
,
fabM
). We also found that
Candida
-derived β1,3-glucans contribute to the EPS matrix structure, while fungal mannan and β-glucan provide sites for GtfB binding and activity. Altogether, we demonstrate a novel mutualistic bacterium-fungus relationship that occurs at a clinically relevant site to amplify the severity of a ubiquitous infectious disease.
Immunomodulatory Glycan Lacto-N-Fucopentaose III Requires Clathrin-Mediated Endocytosis To Induce Alternative Activation of Antigen-Presenting Cells
Authors: Srivastava Leena , Tundup Smanla , Choi Beak-San , Norberg Thomas , Harn Donald
Published: February 2014

The mechanism of alternative activation of antigen-presenting cells (APCs) is largely unknown. Lacto-N-fucopentaose III (LNFPIII) is a biologically conserved pentasaccharide that contains the Lewisxtrisaccharide. LNFPIII conjugates and schistosome egg antigens, which contain the Lewisxtrisaccharide, drive alternative activation of APCs and induce anti-inflammatory responsesin vivo, preventing inflammation-based diseases, including psoriasis, transplant organ rejection, and metabolic disease. In this study, we show that LNFPIII conjugates and schistosome egg antigens interact with APCs via a receptor-mediated process, requiring internalization of these molecules through a clathrin/dynamin-dependent but caveolus-independent endocytic pathway. Using inhibitors/small interfering RNA (siRNA) against dynamin and clathrin, we show for the first time that endocytosis of Lewisx-containing glycans is required to drive alternative maturation of antigen-presenting cells and Th2 immune responses. We identified mouse SIGNR-1 as a cell surface receptor for LNFPIII conjugates. Elimination of SIGNR-1 showed no effect on uptake of LNFPIII conjugates, suggesting that other receptors bind to and facilitate uptake of LNFPIII conjugates. We demonstrate that disruption of actin filaments partially prevented the entry of LNFPIII conjugates into APCs and that LNFPIII colocalizes with both early and late endosomal markers and follows the classical endosomal pathway leading to lysosome maturation. The results of this study show that the ability of LNFPIII to induce alternative activation utilizes a receptor-mediated process that requires a dynamin-dependent endocytosis. Thus, key steps have been defined in the previously unknown mechanism of alternative activation that ultimately leads to induction of anti-inflammatory responses.
Invasion of Oral and Aortic Tissues by Oral Spirochete Treponema denticola in ApoE
−/−
Mice Causally Links Periodontal Disease and Atherosclerosis
Authors: Chukkapalli Sasanka S. , Rivera Mercedes F. , Velsko Irina M. , Lee Ju-Youn , Chen Hao , Zheng Donghang , Bhattacharyya Indraneel , Gangula Pandu R. , Lucas Alexandra R. , Kesavalu Lakshmyya
Published: February 2014

Treponema denticola
is a predominantly subgingival oral spirochete closely associated with periodontal disease and has been detected in atherosclerosis. This study was designed to evaluate causative links between periodontal disease induced by chronic oral
T. denticola
infection and atherosclerosis in hyperlipidemic ApoE
−/−
mice. ApoE
−/−
mice (
n
= 24) were orally infected with
T. denticola
ATCC 35404 and were euthanized after 12 and 24 weeks.
T. denticola
genomic DNA was detected in oral plaque samples, indicating colonization of the oral cavity. Infection elicited significantly (
P
= 0.0172) higher IgG antibody levels and enhanced intrabony defects than sham infection.
T. denticola
-infected mice had higher levels of horizontal alveolar bone resorption than sham-infected mice and an associated significant increase in aortic plaque area (
P
≤ 0.05). Increased atherosclerotic plaque correlated with reduced serum nitric oxide (NO) levels and increased serum-oxidized low-density lipoprotein (LDL) levels compared to those of sham-infected mice.
T. denticola
infection altered the expression of genes known to be involved in atherosclerotic development, including the leukocyte/endothelial cell adhesion gene (
Thbs4
), the connective tissue growth factor gene (
Ctgf
), and the selectin-E gene (
Sele
). Fluorescent
in situ
hybridization (FISH) revealed
T. denticola
clusters in both gingival and aortic tissue of infected mice. This is the first study examining the potential causative role of chronic
T. denticola
periodontal infection and vascular atherosclerosis
in vivo
in hyperlipidemic ApoE
−/−
mice.
T. denticola
is closely associated with periodontal disease and the rapid progression of atheroma in ApoE
−/−
mice. These studies confirm a causal link for active oral
T. denticola
infection with both atheroma and periodontal disease.
Socioeconomic position across life and body composition in early old age: findings from a British birth cohort study
Authors: Bann David , Cooper Rachel , Wills Andrew K , Adams Judith , Kuh Diana ,   on behalf of the NSHD scientific and data collection team
Published: February 2014

Background

Previous studies have reported associations between lower lifetime socioeconomic position (SEP) and higher body mass index in adulthood, but few have examined associations with direct measures of fat and lean mass which are likely to have independent roles in health and physical functioning.

Methods

We examined associations of SEP across life with dual-energy X-ray absorptiometry measures of fat and lean mass at 60–64 years using data from a total of 1558 men and women participating in the Medical Research Council (MRC) National Survey of Health and Development. We also examined whether associations of childhood SEP with fat and lean mass were explained by preadulthood weight gain (birth weight, 0–7 and 7–20 years) and adult SEP.

Results

Lower SEP across life was associated with higher fat mass and higher android to gynoid fat mass ratio. For example, the mean difference in fat mass index comparing the lowest with the highest paternal occupational class at 4 years (slope index of inequality) was 1.04 kg/m1.2in men (95% CI 0.09 to 1.99) and 2.61 in women (1.34 to 3.89), equivalent to a 8.6% and 16.1% difference, respectively. After adjustment for fat mass, lower SEP across life was associated with lower lean mass in women, while only contemporaneous household income was associated in men. Associations between childhood SEP and outcomes were partly explained by preadulthood weight gain and adult SEP.

Conclusions

This study identified lifetime socioeconomic patterning of fat and lean mass in early old age. This is likely to have important implications and may partly explain socioeconomic inequalities in health and physical functioning.
Literature as an exploration of the phenomenology of schizophrenia: disorder and recovery in Denis Johnson'sJesus’ Son
Authors: Hamm Jay A , Leonhardt Bethany L , Fogley Rebecca L , Lysaker Paul H
Published: February 2014

When read as a fictional psychosis narrative,Jesus’ Son,a collection of short stories by Denis Johnson, reveals important elements of the phenomenology of schizophrenia and recovery. It is possible thatJesus’ Son, as a work of fiction, may be able to uniquely add depth and nuance to an understanding of the phenomenology of schizophrenia involving a state of psychological fragmentation, an ever-changing interpersonal field and a loss of personal agency. In addition, by following the protagonist inJesus’ Sonas he begins to resolve some of his difficulties, the book also offers an individualised account of recovery. The authors detail how the book reveals these insights about schizophrenia and recovery and suggest that these elements are intertwined in such a manner that leads to a profound disruption of self-experience, characterised by a collapse of metacognitive processes.Jesus’ Sonmay add depth to our understanding of the subjective experience of schizophrenia and recovery, and also may serve as one example in which the study of humanities offers an opportunity to explore the human elements in the most profound forms of suffering.
Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm
Authors: Ito Hidemichi , Morishima Hiroyuki , Onodera Hidetaka , Wakui Daisuke , Uchida Masashi , Sase Taigen , Oshio Kotaro , Tanaka Yuichiro
Published: February 2014

A 79-year-old woman presented with a subarachnoid hemorrhage. Angiography revealed pseudoaneurysm formation due to rupture of a true saccular anterior communicating artery aneurysm. Coil embolization, limited to the true aneurysm, was performed successfully with a favorable clinical outcome. This procedure can be considered as an alternative treatment option for similar aneurysms in cases where surgical clipping is contraindicated.
The addition of terminal alkynes to dimesitylfluorenylidenegermane
Authors: Tashkandi Nada Y. , Pavelka Laura C. , Hanson Margaret A. , Baines Kim M.
Published: February 2014

A variety of terminal alkynes were added to dimesitylfluorenylidenegermane, Mes2Ge=CR2 (where CR2 = fluorenylidene). The addition of phenylacetylene and 1-hexyne to Mes2Ge=CR2 gave a germacyclohexene via a cycloaddition where the germene acts as the 4π component and the alkyne as the 2π component. Through the use of a mechanistic probe, trans-(2-phenylcyclopropyl)-acetylene, the reaction was postulated to proceed through a concerted [2+4] cycloaddition. The addition of ethoxyacetylene to the germene produced both a [2+2] cycloadduct, a germacyclobutene, and a [2+4] cycloadduct, a germacyclohexene. The results of this study are compared to the results of the addition of alkynes to Mes2Ge=CHCH2-t-Bu.
Electrochemical studies of ascorbic acid, dopamine, and uric acid at adl-norvaline-deposited glassy carbon electrode
Authors: Kamel Mahmoud Mohamed , Abdalla Ehab Mahmoud , Ibrahim Mohamed Sayed , Temerk Yassin Mohamed
Published: February 2014

The electrochemical behavior of ascorbic acid (AA), dopamine (DA), and uric acid (UA) on a dl-norvaline-modified glassy carbon electrode (GCE) was studied by cyclic voltammetry. The bare GCE failed to distinguish the oxidation peaks of AA, DA, and UA in phosphate-buffered solution (pH 5.0), while the dl-norvaline-modified GCE could separate them efficiently. In differential pulse voltammetric (DPV) measurements, the modified electrode resolved the overlapped voltammetric responses of AA, DA, and UA into three well-defined voltammetric peaks. Under optimum conditions, the anodic peak currents of DPV for AA, DA, and UA were proportional to the concentration in the range of 20–400, 1–40, and 15–180 μmol/L, respectively, with a correlation coefficient (r) of around 0.998. The detection limits were 5, 0.3, and 10 μmol/L (S/N = 3) for AA, DA, and UA, respectively. Satisfactory results were achieved for the determination of AA in vitamin C tablets, DA in a dopamine ampoule sample, and UA in human blood serum samples.
Comparison of innovative nano fly ash with conventional fly ash and nano-silica
Authors: Kim Seong-Soo , Hooton R. Doug , Cho Tae-Jun , Lee Jeong-Bae
Published: February 2014

This report is an experimental study on the nano-powdering of fly ash and the improvement of cement performance by nano fly ash. Mortars with nano fly ash or nano-silica produced by a physical method are compared with mortar without a nano-binder. Mortar with nano-silica showed rapid setting. However, mortar with fly ash or nano fly ash exhibited delayed setting. The smaller the particle sizes, the higher is the compressive strength, demonstrating that mortar with nano fly ash shows superior performance with higher compressive strength from the beginning. Durability assessments revealed that chloride penetration resistance increased by 70% for mortar with nano fly ash or nano-silica. This shows that mortar with a smaller particle binder has excellent carbonation resistance. Nano-powdering effectively enhances the activation of a pozzolanic reaction and provides densely charged effects. These changes solve the problem of initial strength reduction — the greatest weakness of fly ash.
Nonlinear electroviscoelastic potential flow instability theory of two superposed streaming dielectric fluids
Authors: El-Sayed M.F. , Eldabe N.T. , Haroun M.H. , Mostafa D.M.
Published: February 2014

The nonlinear electrohydrodynamic Kelvin–Helmholtz instability of two superposed viscoelastic Walters B′ dielectric fluids in the presence of a tangential electric field is investigated in three dimensions using the potential flow analysis. The method of multiple scales is used to obtain a dispersion relation for the linear problem, and a nonlinear Ginzburg–Landau equation with complex coefficients for the nonlinear problem. The linear and nonlinear stability conditions are obtained and discussed both analytically and numerically. In the linear stability analysis, we found that the fluid velocities and kinematic viscosities have destabilizing effects, and the electric field, kinematic viscoelasticities, and surface tension have stabilizing effects; and that the system in the three-dimensional disturbances is more stable than in the corresponding case of two-dimensional disturbances. While in the nonlinear analysis, for both two- and three-dimensional disturbances, we found that the fluid velocities, surface tension, and kinematic viscosities have destabilizing effects, and the electric field, kinematic viscoelasticities have stabilizing effects, and that the system in the three-dimensional disturbances is more unstable than its behavior in the two-dimensional disturbances for most physical parameters except the kinematic viscosities.
Vector currents of massive neutrinos of an electroweak nature
Authors: Sharafiddinov Rasulkhozha S.
Published: February 2014

The mass of an electroweakly interacting neutrino consists of the electric and weak parts responsible for the existence of its charge, charge radius, and magnetic moment. Such connections explain the formation of paraneutrinos, for example, at the polarized neutrino electroweak scattering by spinless nuclei. We derive the structural equations that relate the self-components of mass to charge, charge radius, and magnetic moment of each neutrino as a consequence of unification of fermions of a definite flavor. They indicate the availability of neutrino universality and require following its logic in a constancy law dependence of the size implied from the multiplication of a weak mass of neutrino by its electric mass. According to this principle, all Dirac neutrinos of a vector nature, regardless of the difference in their masses, have the same charge, an identical charge radius, as well as an equal magnetic moment. Thereby, the possibility appears of establishing the laboratory limits of weak masses of the investigated types of neutrinos. Finding estimates show clearly that the earlier measured properties of these particles may testify in favor of the unified mass structure of their interaction with any of the corresponding types of gauge fields.
Photodetachment of H– ion in perpendicular electric and magnetic fields near a metal surface
Authors: Wang De-hua
Published: February 2014

The photodetachment of the H– ion in perpendicular electric and magnetic fields near a metal surface has been investigated on the basis of the semiclassical closed-orbit theory. Firstly, we give a clear physical picture of the detached electron’s movement and find out the closed orbits of this system. Then we put forward an analytical formula for calculating the photodetachment cross section. It is found that the perpendicular electric and magnetic fields can produce some interesting effects. As the magnetic field is relatively weak, the influence of the electric field and the electrostatic potential dominates and the oscillatory structure in the photodetachment cross section exhibits a smoothly oscillating curve. As we keep the electric field and the ion–surface distance unchanged, with the increase of the magnetic field strength, the number of closed orbits is increased and the oscillatory structure in the photodetachment cross section is characterized by broad Landau level envelops. Therefore, we can use the perpendicular electric and magnetic fields to control the photodetachment of H– near a metal surface. Our study may guide future experimental research on the photodetachment microscopy of negative ion in external fields near surfaces.
LOWER QUADRANT DYSFUNCTIONS AMONG DENTISTS — PREVALENCE AND RISK FACTORS
Authors: Agrawal Parul Raj , Girish N.
Published: February 2014

Background: The prevalence of musculoskeletal complaints in dentists is high although relatively few studies had focus in this profession. Various studies have been done to record stress levels and self-perceived health and health-related behaviors of dentists in other countries but limited data are available among the Indian dentists indicating the need to evaluate the same. Aim of this study was to find out the prevalence of lower quadrant dysfunctions among dentist and to investigate the risk factors for musculoskeletal complaints. Methodology: It was a cross-sectional study. A questionnaire interview was carried out among 85 dentists of Manipal, Karnataka, India. Questions include data on physical workload, perceived general health and the occurrence of musculoskeletal complaints pertaining to lower quadrant in the past 12 months, and various physical risk factors at the workplace. Statistical Analysis: Results were analyzed using descriptive statistics Results: Among all the area low-back pain (LBP) was the most prevalent musculoskeletal complaint, reported by 68% of the subjects followed by knee—35%, foot and heel—26%. Conclusions: Prevalence of Lower quadrant dysfunctions among dentist was 33%. The physical load, awkward posture and lack of physical activity among dentists seem to put them at risk for the occurrence of musculoskeletal disorders. Clinical Relevance: Identification of the risk factors may allow us to do a focused intervention in preventing these work-related musculoskeletal symptoms.
PEOPLE WATCH
Authors: Peitsch Manuel
Published: February 2014

Challenged to Improve.
The fréchet distance revisited and extended
Authors: Har-Peled Sariel , Raichel Benjamin
Published: February 2014

Given two simplicial complexes in R
d
and start and end vertices in each complex, we show how to compute curves (in each complex) between these vertices, such that the weak Fréchet distance between these curves is minimized. As a polygonal curve is a complex, this generalizes the regular notion of weak Fréchet distance between curves. We also generalize the algorithm to handle an input of
k
simplicial complexes.

Using this new algorithm, we can solve a slew of new problems, from computing a mean curve for a given collection of curves to various motion planning problems. Additionally, we show that for the mean curve problem, when the
k
input curves are
c
-packed, one can (1+ε-approximate the mean curve in near-linear time, for fixed
k
and ε.

Additionally, we present an algorithm for computing the strong Fréchet distance between two curves, which is simpler than previous algorithms and avoids using parametric search.
Comprehensive formal verification of an OS microkernel
Authors: Klein Gerwin , Andronick June , Elphinstone Kevin , Murray Toby , Sewell Thomas , Kolanski Rafal , Heiser Gernot
Published: February 2014

We present an in-depth coverage of the comprehensive machine-checked formal verification of seL4, a general-purpose operating system microkernel.

We discuss the kernel design we used to make its verification tractable. We then describe the functional correctness proof of the kernel's C implementation and we cover further steps that transform this result into a comprehensive formal verification of the kernel: a formally verified IPC fastpath, a proof that the binary code of the kernel correctly implements the C semantics, a proof of correct access-control enforcement, a proof of information-flow noninterference, a sound worst-case execution time analysis of the binary, and an automatic initialiser for user-level systems that connects kernel-level access-control enforcement with reasoning about system behaviour. We summarise these results and show how they integrate to form a coherent overall analysis, backed by machine-checked, end-to-end theorems.

The seL4 microkernel is currently not just the only general-purpose operating system kernel that is fully formally verified to this degree. It is also the only example of formal proof of this scale that is kept current as the requirements, design and implementation of the system evolve over almost a decade. We report on our experience in maintaining this evolving formally verified code base.
Towards a resilient deployment and configuration infrastructure for fractionated spacecraft
Authors: Pradhan Subhav , Otte William R. , Dubey Abhishek , Gokhale Aniruddha , Karsai Gabor
Published: February 2014

Fractionated spacecraft are clusters of small, independent modules that interact wirelessly to realize the functionality of a traditional monolithic spacecraft. System F6 (F6 stands for Future, Fast, Flexible, Fractionated, Free-Flying spacecraft) is a DARPA program for fractionated spacecraft. Software applications in F6 are implemented in the context of the F6 Information Architecture Platform (IAP), which provides component-based abstractions for composing distributed applications. The lifecycle of these distributed applications must be managed autonomously by a deployment and configuration (D&C) infrastructure, which can redeploy and reconfigure the running applications in response to faults and other anomalies that may occur during system operation. Addressing these D&C requirements is hard due to the significant fluctuation in resource availabilities, constraints on resources, and safety and security concerns. This paper presents the key architectural ideas that are required in realizing such a D&C infrastructure.
Toward predictable, efficient, system-level tolerance of transient faults
Authors: Song Jiguo , Parmer Gabriel
Published: February 2014

As embedded and real-time systems increase in complexity, and as chip process technologies continually decrease feature size, transient faults increasingly threaten system failure. This paper introduces C
3
, an system to tolerate
system-level faults
(
e.g
. in the scheduler). When considering
predictable
recovery of system-level components, we introduce
recovery interference
, a side-effect of system-level recovery that causes possibly unbounded priority inversion. We discuss an interface-driven recovery technique that is effective, efficient, and uses
on-demand
recovery to avoid recovery interference.
A new concept for system-level design of runtime reconfigurable real-time systems
Authors: Luppold Arno , Menhorn Benjamin , Falk Heiko , Slomka Frank
Published: February 2014

This concept paper proposes a new system-level design methodology for runtime reconfigurable adaptive heterogeneous systems in a real-time environment. Today, among those approaches dealing with runtime reconfiguration and hardware/software co-design, compliance with hard real-time conditions is not guaranteed. Our approach will fill this gap. In contrast to other approaches, we apply methods of real-time analysis to embedded reconfigurable systems. An extended compiler and a runtime resource manager guarantee both synthesis and reconfiguration in a (hard) real-time environment. With this approach, the system can adapt to changes in requirements and operational environments during runtime.