bluuebunny/crossref_metadata_2025 huggingface dataset:
Preadmission Screening of Adults Highlights Previously Unrecognized Carriage of Panton-Valentine Leukocidin-Positive Methicillin-Resistant Staphylococcus aureus in London: a Cause for Concern?
Authors: Pantelides Nicholas M. , Gopal Rao Guduru , Charlett Andre , Kearns Angela M.
Published: July 2012

In the first study of its kind in the United Kingdom, we describe the colonization rate of ciprofloxacin-sensitive Panton-Valentine leukocidin-positive methicillin-resistant
Staphylococcus aureus
(PVL-MRSA) in adult patients who were screened systematically at the time of hospital admission. We also describe the molecular characteristics of PVL-MRSA and antibiotic resistance phenotypes. A total of 55,760 specimens were screened for MRSA between April 2008 and December 2010. MRSA was identified in 1,998 specimens, and ciprofloxacin-susceptible (CSMRSA) isolates (385/1,998, or 19.3%) were subjected to PVL testing. Of these, 70 (18.1%) were identified as PVL-CSMRSA. During the study period, the MRSA colonization rate decreased from 4.6% to 2.8%. In contrast, the colonization rate of PVL-CSMRSA increased over time, rising from 0.075% in 2008 and 0.07% in 2009 to 0.22% in 2010. The mean patient age was 52 years (range, 18 to 90 years); over two-thirds were male. Seven different lineages of PVL-CSMRSA were identified. Over the 3 years, the Southwest Pacific clone (CC30) was dominant in our population. The CC5 clone was detected once in 2008 and not at all in 2009 but accounted for a third of all PVL-CSMRSA strains in 2010. This lineage was commonly associated with clindamycin resistance and, less frequently, tetracycline resistance. We conclude that there is hitherto unrecognized low-level carriage of PVL-CSMRSA among patients being admitted to hospitals in northwest London. We observed the emergence of the CC5 clone in 2010 with associated clindamycin and tetracycline resistance.
Performance of Clinical Laboratories in South African Parasitology Proficiency Testing Surveys between 2004 and 2010
Authors: Poonsamy Bhavani , Dini Leigh , Frean John
Published: July 2012

Performance in proficiency testing (PT) schemes is an objective measure of a laboratory's best performance. We examined the performance of participants in two parasitology PT schemes in South Africa from 2004 through 2010. The average rates of acceptable scores over the period were 58% and 66% for the stool and blood parasite schemes, respectively. In our setting, participation in PT alone is insufficient to improve performance; a policy that provides additional resources and training seems necessary.
High Metabolic Potential May Contribute to the Success of ST131 Uropathogenic Escherichia coli
Authors: Gibreel Tarek M. , Dodgson Andrew R. , Cheesbrough John , Bolton Frederick J. , Fox Andrew J. , Upton Mathew
Published: July 2012

Uropathogenic
Escherichia coli
(UPEC) is the predominant cause of urinary tract infection in both hospital and community settings. The recent emergence of multidrug-resistant clones like the O25b:H4-ST131 lineage represents a significant threat to health, and numerous studies have explored the virulence potential of these organisms. Members of the ST131 clone have been described as having variable carriage of key virulence factors, and it has been suggested that additional unidentified factors contribute to virulence. Here we demonstrated that ST131 isolates have high metabolic potential and biochemical profiles that distinguish them from isolates of many other sequence types (STs). A collection of 300 UPEC isolates recovered in 2007 and 2009 in the Northwest region of England were subjected to metabolic profiling using the Vitek2 Advanced Expert System (AES). Of the 47 tests carried out, 30 gave a positive result with at least one of the 300 isolates examined. ST131 isolates demonstrated significant association with eight tests, including those for peptidase, decarboxylase, and alkalinization activity. Metabolic activity also correlated with antibiotic susceptibility profiles, with resistant organisms displaying the highest metabolic potential. This is the first comprehensive study of metabolic potential in the ST131 lineage, and we suggest that high metabolic potential may have contributed to the fitness of members of the ST131 clone, which are able to exploit the available nutrients in both the intestinal and urinary tract environments.
Serological Profile of Torque Teno Sus Virus Species 1 (TTSuV1) in Pigs and Antigenic Relationships between Two TTSuV1 Genotypes (1a and 1b), between Two Species (TTSuV1 and -2), and between Porcine and Human Anelloviruses
Authors: Huang Yao-Wei , Harrall Kylie K. , Dryman Barbara A. , Opriessnig Tanja , Vaughn Eric M. , Roof Michael B. , Meng Xiang-Jin
Published: July 2012

The family
Anelloviridae
includes human and animal torque teno viruses (TTVs) with extensive genetic diversity. The antigenic diversity among anelloviruses has never been assessed. Using torque teno sus virus (TTSuV) as a model, we describe here the first investigation of the antigenic relationships among different anelloviruses. Using a TTSuV genotype 1a (TTSuV1a) or TTSuV1b enzyme-linked immunosorbent assay (ELISA) based on the respective putative ORF1 capsid antigen and TTSuV1-specific real-time PCR, the combined serological and virological profile of TTSuV1 infection in pigs was determined and compared with that of TTSuV2. TTSuV1 is likely not associated with porcine circovirus-associated disease (PCVAD), because both the viral loads and antibody levels were not different between affected and unaffected pigs and because there was no synergistic effect of concurrent PCV2/TTSuV1 infections. We did observe a higher correlation of IgG antibody levels between anti-TTSuV1a and -TTSuV1b than between anti-TTSuV1a or -1b and anti-TTSuV2 antibodies in these sera, implying potential antigenic cross-reactivity. To confirm this, rabbit antisera against the putative capsid proteins of TTSuV1a, TTSuV1b, or TTSuV2 were generated, and the antigenic relationships among these TTSuVs were analyzed by an ELISA and by an immunofluorescence assay (IFA) using PK-15 cells transfected with one of the three TTSuV ORF1 constructs. The results demonstrate antigenic cross-reactivity between the two genotypes TTSuV1a and TTSuV1b but not between the two species TTSuV1a or -1b and TTSuV2. Furthermore, an anti-genogroup 1 human TTV antiserum did not react with any of the three TTSuV antigens. These results have important implications for an understanding of the diversity of anelloviruses as well as for the classification and vaccine development of TTSuVs.
Comparable Fitness and Transmissibility between Oseltamivir-Resistant Pandemic 2009 and Seasonal H1N1 Influenza Viruses with the H275Y Neuraminidase Mutation
Authors: Wong Diana D. Y. , Choy Ka-Tim , Chan Renee W. Y. , Sia Sin Fun , Chiu Hsin-Ping , Cheung Peter P. H. , Chan Michael C. W. , Peiris J. S. Malik , Yen Hui-Ling
Published: July 2012

Limited antiviral compounds are available for the control of influenza, and the emergence of resistant variants would further narrow the options for defense. The H275Y neuraminidase (NA) mutation, which confers resistance to oseltamivir carboxylate, has been identified among the seasonal H1N1 and 2009 pandemic influenza viruses; however, those H275Y resistant variants demonstrated distinct epidemiological outcomes in humans. Specifically, dominance of the H275Y variant over the oseltamivir-sensitive viruses was only reported for a seasonal H1N1 variant during 2008-2009. Here, we systematically analyze the effect of the H275Y NA mutation on viral fitness and transmissibility of A(H1N1)pdm09 and seasonal H1N1 influenza viruses. The NA genes from A(H1N1)pdm09 A/California/04/09 (CA04), seasonal H1N1 A/New Caledonia/20/1999 (NewCal), and A/Brisbane/59/2007 (Brisbane) were individually introduced into the genetic background of CA04. The H275Y mutation led to reduced NA enzyme activity, an increased

K
m

for 3′-sialylactose or 6′-sialylactose, and decreased infectivity in mucin-secreting human airway epithelial cells compared to the oseltamivir-sensitive wild-type counterparts. Attenuated pathogenicity in both RG-CA04
NA-H275Y
and RG-CA04 × Brisbane
NA-H275Y
viruses was observed in ferrets compared to RG-CA04 virus, although the transmissibility was minimally affected. In parallel experiments using recombinant Brisbane viruses differing by hemagglutinin and NA, comparable direct contact and respiratory droplet transmissibilities were observed among RG-NewCal
HA,NA
, RG-NewCal
HA,NA-H275Y
, RG-Brisbane
HA,NA-H275Y
, and RG-NewCal
HA
× Brisbane
NA-H275Y
viruses. Our results demonstrate that, despite the H275Y mutation leading to a minor reduction in viral fitness, the transmission potentials of three different antigenic strains carrying this mutation were comparable in the naïve ferret model.
A rare genetic disorder causing persistent severe neonatal hypoglycaemia the diagnostic workup
Authors: Francescato Gaia , Salvatoni Alessandro , Persani Luca , Agosti Massimo
Published: July 2012

We report a case of familial glucocorticoid deficiency (FGD), a rare genetic autosomal-recessive disorder with typical hyperpigmentation of the skin and mucous membranes, severe hypoglycaemia, occasionally leading to seizures and coma, feeding difficulties, failure to thrive and infections. A newborn child was admitted, on his second day of life, to our neonatal intensive care unit because of seizures and respiratory insufficiency. Hyperpigmentation was not evident due to his Senegalese origin. The clinical presentation led us to consider a wide range of diagnostic hypothesis. Laboratory findings brought us to the diagnosis of FGD that was confirmed by molecular analysis showing an MC2R:p.Y254C mutation previously reported as causative of type 1 FGD and two novel heterozygous non-synonymous single-nucleotide polymorphisms in exon 2 and 3 of melanocortin 2 receptor accessory protein-α, whose role in the disease is currently unknown. The importance of an early collection and storage of blood samples during hypoglycaemic event is emphasised.
Sclerochoroidal calcification associated with Albright's hereditary osteodystrophy
Authors: Lee Helena , Kumar Periyasamy , Deane James
Published: July 2012

A 47-year-old woman presented with bilateral gradual loss of vision, ocular discomfort and seeing a black shadow in her right visual field over 6 months duration. Her medical history was extensive including: developmental delay, pseudohypoparathyroidism, hypertension, spinal stenosis, epilepsy and suspected idiopathic intracranial hypertension. Ocular examination revealed choroidal elevation in both eyes, which were highly ecogenic on ecography and confirmed to be calcifications of choroids on CT scan in her both eyes. She had subnormal vision and reduced colour vision in her both eyes. Electrodiagostic studies suggested rod dysfunction. She had typical features of Albright's hereditary dystrophy and was positive for the GNAS 1 mutation. She is currently being monitored by ophthalmologlists and is also under a medical team undergoing further assessment with regard to her treatment.
Ophthalmic manifestations of atypical IgD multiple myeloma
Authors: Edmunds Matthew R , Cikatricis Peter , Mukherji Subhanjan , Bowyer Jeremy D
Published: July 2012

A previously healthy 32-year-old Caucasian female presented with sudden-onset horizontal diplopia following a paroxysm of coughing. She had recently sustained a pubic ramus fracture during an innocuous fall and had also noted a firm lump developing at the right side of her forehead. On examination, she had a right fronto-temporal mass. Visual acuities were 6/6 bilaterally. There was reduced abduction of the right eye, bilateral white, granular corneal opacities and evidence of bilateral optic disc swelling. Haematological investigations revealed normocytic anaemia, hypercalcaemia and raised erythrocyte sedimentation rate (ESR). CT showed lytic foci throughout the skull, ribs, scapulae, spine, pelvis and upper femora. Serum protein electrophoresis revealed immunoglobulin D (IgD)-kappa paraproteinaemia; urine electrophoresis showed free light chain kappa and bone marrow biopsy demonstrated 87% plasma cells. A diagnosis of IgD multiple myeloma was made, with subsequent chemotherapeutic treatment and eventual autologous stem cell transplant resulting in resolution of neuro-ophthalmic manifestations and prolonged disease remission.
Do we create ecological traps when trying to emulate natural disturbances? A test on songbirds of the northern hardwood forest1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: Villard Marc-André , D’Astous Émilie , Haché Samuel , Poulin Jean-François , Thériault Stéphane
Published: July 2012

Forest management inspired from natural disturbances is often claimed to have more benign effects on biodiversity than more traditional approaches but this premise has rarely been tested. In the northern hardwood forest, selection harvesting could be seen as a surrogate for the combined effects of windthrow, moderate ice storms, and senescence. Here, we quantified the response of two focal species of forest birds (Brown Creeper ( Certhia americana (Bonaparte, 1838)) and Ovenbird ( Seiurus aurocapilla (Linnaeus, 1766))) to this treatment (30%–40% basal area removal) in the first 5 years post-harvest using a replicated field experiment. We tested the possibility that selection harvesting creates ecological traps whereby individuals show a preference for a habitat type where their fitness is lower. We found that both focal species actually seemed to prefer control plots, where they reached a higher density than in treated plots. There was no evidence for a treatment effect on per capita productivity in either species. Hence, there was no evidence for an ecological trap. However, large-scale application of selection harvesting may have ecologically significant effects on productivity of the focal species per unit area of habitat. Future studies should test whether selection harvesting creates ecological traps for species naturally associated with canopy gaps.
Tree species versus regional controls on ecosystem properties and processes: an example using introduced Pinus contorta in Swedish boreal forests1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: McIntosh Anne C.S. , Macdonald S. Ellen , Gundale Michael J.
Published: July 2012

When species are introduced into new regions, there is great uncertainty whether the trait differences of the introduced species or regional factors, such as climate or edaphic properties, will serve as the dominant control of ecosystem properties or processes. In this study, we examined whether the introduction of Pinus contorta Douglas ex Loudon into Sweden has altered forest floor properties and processes or whether these properties are more strongly controlled by regional factors. We compared forest floor pH, potential N mineralization rates, bulk density, litter and forest floor depths, C and N concentrations and pool sizes, C:N ratios, and soil microbial communities using substrate-induced respiration and phospholipid fatty acid analysis among stands of introduced P. contorta (SwPc), native Swedish Pinus sylvestris L. (SwPs), and native Canadian P. contorta (CaPc). For most forest floor properties (pH, net NH4+ mineralization, bulk density, N mass, and the microbial phospholipid fatty acid community structure), SwPc sites were more similar to SwPs than to CaPc, whereas litter and forest floor depth were significantly higher in SwPc than the two other forest types. Our findings suggest that regional factors exerted a stronger control on most forest floor properties and processes than did species differences between the two Pinus species for the regions we studied.
Browning of the landscape of interior Alaska based on 1986-2009 Landsat sensor NDVI
Authors: Baird Rebecca A. , Verbyla David , Hollingsworth Teresa N.
Published: July 2012

We used a time series of 1986–2009 Landsat sensor data to compute the Normalized Difference Vegetation Index (NDVI) for 30 m pixels within the Bonanza Creek Experimental Forest of interior Alaska. Based on simple linear regression, we found significant (p < 0.05) declining trends in mean NDVI of three dominant landscape types of floodplains, lowlands, and uplands. At smaller patch sizes, similar declining trends occurred among topographic classes of north- and south-facing slopes and valley bottoms and among forest classes, including black spruce (Picea mariana (Mill.) B.S.P.). Significant positive trends in mean NDVI occurred only in areas that were recently burned, whereas wetlands had no significant trend. The greatest departure from the NDVI trend line occurred following the 2004 drought for all forest classes except black spruce, which dominates the coldest sites, and balsam poplar (Populus balsamifera L.), which occurs on low, moist terraces within the Tanana River floodplain. The consistent long-term declining trend at several spatial scales may be due to a regional climatic regime shift that occurred in the mid-1970s.
Evaluating marginal and conditional predictions of taper models in the absence of calibration data
Authors: de-Miguel Sergio , Mehtätalo Lauri , Shater Zuheir , Kraid Bassel , Pukkala Timo
Published: July 2012

A systematic evaluation of nonlinear fixed- and mixed-effects taper models in volume prediction was conducted. Among 33 taper equations, the best 1- to 10-parameter fixed-effects models according to fitting statistics were further analysed by comparing their predictions against the modelling data and an independent data set. Three alternative prediction strategies were compared using the best equation (Kozak II) in the absence of calibration data (the usual situation in forestry practice). Strategy 1 used a fixed-parameter model (marginal model), strategy 2 utilized the fixed part of a mixed-effects model (conditional model), and strategy 3 calculated a marginal prediction based on the mixed-effects model by averaging the predictions over the estimated distribution of random effects. Strategies 1 and 3 performed better than strategy 2 in model evaluation (in modelling data) and model validation (independent data). Strategy 3 was less biased than strategy 1 in model validation, and both had the same mean squared deviation. Strategy 3 shares the most advantageous features of the other prediction methods and is therefore recommended for forestry practice and for further research in different modelling disciplines within forest science.
Influence of recent fire season and severity on black spruce regeneration in spruce–moss forests of Quebec, Canada1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: Veilleux-Nolin Mélanie , Payette Serge
Published: July 2012

Postfire regeneration problems compromise the maintenance of closed-crown forests of eastern Canada, often shifting toward lichen woodlands. Compounded disturbances like successive fires or insect outbreaks followed by fire may be responsible for this shift. Leaving behind unfavourable seedbeds for the germination of black spruce ( Picea mariana (Mill.) B.S.P.) seeds, low-severity fires may also be involved in this transformation. The severity of recent fires and their impact on black spruce regeneration were evaluated using 13 stands burned in spring or summer within the closed-crown forest in Quebec during the last 20 years. Two ecological indicators were used to characterize fire severity: thickness of residual organic material and recovery of plant species. Regardless of the season, the ground of all burned stands was covered with a thick layer of residual organic matter. Blackened organic matter and ericaceous vegetation, indicating the passage of a low-severity fire, were widespread in all sites whereas acrocarpous mosses and bare mineral soil, indicating the passage of a severe fire, were uncommon. The preponderance of the thick layer of residual organic material blackened at the surface can explain the failure of regeneration in most studied sites. Low-severity fires are thus among factors probably involved in the expansion of lichen woodlands within the closed-crown forest.
A PÓLYA LATTICE MODEL TO STUDY LEVERAGE DYNAMICS AND CONTAGIOUS FINANCIAL FRAGILITY
Authors: CIRILLO PASQUALE , GALLEGATI MAURO , HÜSLER JÜRG
Published: July 2012

We discuss a special Pólya lattice model to study cascading failures of firms in a simple industrial economy. In particular, every firm is represented by a Pólya-like urn, whose reinforcement is function of time, of the neighboring urns and their compositions, and of a random variable representing systemic risk or fate. The simple idea is to build the dependence among firms by assuming simple balance sheet rules on debts and credits. In detail we assume that the debts of every company are credits for some of its neighbors. Debts and credits are represented by different balls in the urns/firms. At the same time we assume that the riskiness of every firm also depends on the economic wealth of its neighbors and of the economy in general. These simple rules are sufficient to create business cycles, in which the accumulation of debts pushes the economy towards frequent crises. The model can be easily simulated and the results we obtain encourage the development of brand new finitary probabilistic approaches to study firms' behavior and dynamics.
A reassessment of ‘Globigerina bathoniana’ Pazdrowa, 1969 and the palaeoceanographic significance of Jurassic planktic foraminifera from southern Poland
Authors: Hart Malcolm B. , Hudson Wendy , Smart Christopher W. , Tyszka Jarosław
Published: July 2012

Abstract. ‘Globigerina Ooze’, Foraminiferal Ooze or Carbonate Ooze as it is now known, is a widespread and highly characteristic sediment of the modern ocean system. Comparable sediments are much less common in the geological record although, as we describe here, a number of Middle Jurassic carbonate sediments with distinctive assemblages from Central Europe fulfil many of the criteria. One important component of these assemblages in the Middle Jurassic is ‘Globigerina bathoniana’ Pazdrowa, 1969, first described from the Bathonian sediments near Ogrodzieniec (Poland). The generic assignment of this species and other coeval Jurassic taxa is discussed. This species and many of the other early planktic foraminifera evolved in the Aragonite ll Ocean, together with the other two oceanic carbonate producers: the calcareous nannofossils and the calcareous dinoflagellates. The preservation of carbonate sediments with abundant planktic foraminifera on the sea floor indicates that, by the mid-Jurassic, the carbonate/aragonite compensation depths (and associated lysoclines) must have developed in the water column.
Critical review of Pseudocucurbitidae (Miliolina, Foraminiferea) from the Late Triassic reef environments of the Tethyan area
Authors: Gale Luka , Rettori Roberto , Martini Rossana
Published: July 2012

Abstract. The Late Triassic foraminiferal genera Amphorella, Spiriamphorella, Urnulinella, Pseudocucurbita, Paratintinnina, Costifera and Siculocosta are considered junior synonyms of the genus Cucurbita. Consequently, the number of families of the Milioliporacea (Miliolina) is significantly reduced. The valid species of the genus Cucurbita are considered to be Cucurbita infundibuliforme Jablonský, 1973, C. subsphaerica (Borza & Samuel, 1977a) comb. nov., C. longicollum Senowbari-Daryan, 1983, C. battagliensis (Senowbari-Daryan, 1983) comb. nov., C. cylindrica (Senowbari-Daryan, 1983) comb. nov. and C. floriformis (Altiner et al., 1992) comb. nov..
Corporate Finance and Financial Institutions
Authors: Flannery Mark J.
Published: July 2012

Many corporate finance researchers have avoided analyzing financial institutions, perhaps on the grounds that they are “unique” or “different” from other types of firms. This assessment reflects some unusual features of financial firms' liabilities and a set of governmental regulatory restrictions that have become less pervasive in recent years. In fact, corporate finance theory applies equally well to financial firms, although some modifications are required to recognize the effects of government safety and soundness regulation. Regulated firms' private incentives account for most of the difficulties regulators encounter when trying to craft appropriate oversight mechanisms.
Paying Attention to What Judges Say: New Directions in the Study of Judicial Decision Making
Authors: Bybee Keith J.
Published: July 2012

Judges and scholars often speak about the very same subject in very different terms. Judges regularly provide written explanations of their rulings, and scholars regularly argue that the true determinants of judicial decision making lie beyond the words of the judicial opinion. This review engages lines of research that take the fact of competing judicial and scholarly accounts of judicial decision making as the subject of study. In particular, this review surveys three different bodies of work that explain the enduring divide between judges and scholars in terms of motivated reasoning, judicial crisis, and the contradictory demands placed on the judicial process. These three literatures provide ways of thinking about the rule of law in the United States without dismissing the perspectives of either judges or scholars.
Postgenomic Approaches to Using Corynebacteria as Biocatalysts
Authors: Vertès Alain A. , Inui Masayuki , Yukawa Hideaki
Published: July 2012

Corynebacterium glutamicum exhibits numerous ideal intrinsic attributes as a factory of primary and secondary metabolites. The versatile capabilities of this organism have long been implemented at the industrial scale to produce an array of amino acids at high yields and conversion rates, thereby enabling the development of an entire industry. The postgenomic era provides a new technological platform not only to further optimize the intrinsic attributes of C. glutamicum whole cells as biocatalysts, but also to dramatically expand the product portfolio that can be manufactured by this organism, from amino acids to commodity chemicals. This review addresses the methods and strain optimization strategies enabled by genomic information and associated techniques. Their implementation has provided important additional incremental improvements to the economics of industry-scale manufacturing in which C. glutamicum and its episomal elements are used as a performing host-vector system.
Endoplasmic Reticulum Stress in Nonalcoholic Fatty Liver Disease
Authors: Pagliassotti Michael J.
Published: July 2012

The underlying causes of nonalcoholic fatty liver disease are unclear, although recent evidence has implicated the endoplasmic reticulum in both the development of steatosis and progression to nonalcoholic steatohepatitis. Disruption of endoplasmic reticulum homeostasis, often termed ER stress, has been observed in liver and adipose tissue of humans with nonalcoholic fatty liver disease and/or obesity. Importantly, the signaling pathway activated by disruption of endoplasmic reticulum homeostasis, the unfolded protein response, has been linked to lipid and membrane biosynthesis, insulin action, inflammation, and apoptosis. Therefore, understanding the mechanisms that disrupt endoplasmic reticulum homeostasis in nonalcoholic fatty liver disease and the role of the unfolded protein response in the broader context of chronic, metabolic diseases have become topics of intense investigation. The present review examines the endoplasmic reticulum and the unfolded protein response in the context of nonalcoholic fatty liver disease.
Role of connexin40 in the autoregulatory response of the afferent arteriole
Authors: Sorensen Charlotte Mehlin , Giese Isaiah , Braunstein Thomas Hartig , Brasen Jens Christian , Salomonsson Max , Holstein-Rathlou Niels-Henrik
Published: July 2012

Connexins in renal arterioles affect autoregulation of arteriolar tonus and renal blood flow and are believed to be involved in the transmission of the tubuloglomerular feedback (TGF) response across the cells of the juxtaglomerular apparatus. Connexin40 (Cx40) also plays a significant role in the regulation of renin secretion. We investigated the effect of deleting the Cx40 gene on autoregulation of afferent arteriolar diameter in response to acute changes in renal perfusion pressure. The experiments were performed using the isolated blood perfused juxtamedullary nephron preparation in kidneys obtained from wild-type or Cx40 knockout mice. Renal perfusion pressure was increased in steps from 75 to 155 mmHg, and the response in afferent arteriolar diameter was measured. Hereafter, a papillectomy was performed to inhibit TGF, and the pressure steps were repeated. Conduction of intercellular Ca2+changes in response to local electrical stimulation was examined in isolated interlobular arteries and afferent arterioles from wild-type or Cx40 knockout mice. Cx40 knockout mice had an impaired autoregulatory response to acute changes in renal perfusion pressure compared with wild-type mice. Inhibition of TGF by papillectomy significantly reduced autoregulation of afferent arteriolar diameter in wild-type mice. In Cx40 knockout mice, papillectomy did not affect the autoregulatory response, indicating that these mice have no functional TGF. Also, Cx40 knockout mice showed no conduction of intercellular Ca2+changes in response to local electrical stimulation of interlobular arteries, whereas the Ca2+response to norepinephrine was unaffected. These results suggest that Cx40 plays a significant role in the renal autoregulatory response of preglomerular resistance vessels.
Insignificant effect of secretin in rodent models of polycystic kidney and liver disease
Authors: Wang Xiaofang , Ye Hong , Ward Christopher J. , Chu Jessica Y. S. , Masyuk Tatyana V. , LaRusso Nicholas F. , Harris Peter C. , Chow Billy K. C. , Torres Vicente E.
Published: July 2012

Polycystic kidney (PKD) and liver (PLD) diseases cause significant morbidity and mortality. A large body of evidence indicates that cyclic AMP plays an important role in their pathogenesis. Clinical trials of drugs that reduce cyclic AMP levels in target tissues are now in progress. Secretin may contribute to adenylyl cyclase-dependent urinary concentration and is a major agonist of adenylyl cyclase in cholangiocytes. To investigate the role of secretin in PKD and PLD, we have studied the expression of secretin and the secretin receptor in rodent models orthologous to autosomal recessive ( PCK rat) and dominant ( Pkd2−/WS25mouse) PKD; the effects of exogenous secretin administration to PCK rats, PCK rats lacking circulating vasopressin ( PCKdi/di), and Pkd2−/WS25mice; and the impact of a nonfunctional secretin receptor on disease development in Pkd2−/WS25:SCTR−/−double mutants. Renal and hepatic secretin and secretin receptor mRNA and plasma secretin were increased in both models, and secretin receptor protein was increased in the kidneys and liver of Pkd2−/WS25mice. However, exogenous secretin administered subcutaneously via osmotic pumps had minimal or negligible effects and the absence of a functional secretin receptor had no influence on the severity of PKD or PLD. Therefore, it is unlikely that by itself secretin plays a significant role in the pathogenesis of PKD and/or PLD.
Computational Fluid Dynamics Modeling to Improve Natural Flow Rate and Sweet Pepper Productivity in Greenhouse
Authors: Limtrakarn W. , Boonmongkol P. , Chompupoung A. , Rungprateepthaworn K. , Kruenate J. , Dechaumphai P.
Published: July 2012

Natural flow rate and sweet peppers productivity in tropical greenhouse are improved by CFD simulation is the main objective of this research work. Most of the greenhouse types today are in the arch shape. To develop an improved greenhouse structure for the region, the arch type was built and used as the control model. Mae Sar Mai agriculture research station under the royal project foundation was selected as the field test site. Temperature sensors with data logger were installed to monitor variation of temperature inside the greenhouse. The measured temperature data were used as the boundary conditions for the CFD analysis. A new greenhouse model with two-step roof shape was designed and the air flow behavior was simulated by using CFD. Regarding CFD results the air flow rate of the new model is about 39% higher than that of old model. The maximum temperature of the new model is lower than that of the old one. The sweet paper growths in both greenhouse models were measured and compared. Results show that the new model obtains 4°C lower maximum temperature in day time, 97% in number and 90% in weight higher the first grade pepper productivity than the old one.
Aggregation Scheme with Secure Hierarchical Clustering for Wireless Sensor Networks
Authors: Su Tung-Shih , Huang Mei-Wen , Li Wei-Shou , Hsieh Wen-Shyong
Published: July 2012

In a large-scale wireless sensor network, a topology is needed to gather state-based data from sensor network and efficiently aggregate the data given the requirements of balanced load, minimal energy consumption, and prolonged network lifetime. In this study, we proposed a ring-based hierarchical clustering scheme (RHC) consisting of four phases: predeployment, parent-child relationship building, deployment, and member join phases. Two node types are distributed throughout the network: cluster head nodes (type 1 node) and general sensor nodes (type 2 node). The type 1 node has better battery life, software capability, and hardware features than the type 2 node; therefore, the type 1 node is a better cluster head than type 2 node. Due to our IP naming rules and type 1 nodes as cluster heads, public key cryptography, such as RSA (Rivest, Shamir, Adleman), or ECC (Elliptic Curve Cryptosystem), is easily implanted to our system to strengthen our security. The sink node is the only certification authority in our system, but n level cluster heads can be extended to n level certification authorities if needed, where n is maximum number of level.
Investigation of a Stochastic Inverse Method to Estimate an External Force: Applications to a Wave‐Structure Interaction
Authors: Han S. L. , Kinoshita Takeshi
Published: July 2012

The determination of an external force is a very important task for the purpose of control, monitoring, and analysis of damages on structural system. This paper studies a stochastic inverse method that can be used for determining external forces acting on a nonlinear vibrating system. For the purpose of estimation, a stochastic inverse function is formulated to link an unknown external force to an observable quantity. The external force is then estimated from measurements of dynamic responses through the formulated stochastic inverse model. The applicability of the proposed method was verified with numerical examples and laboratory tests concerning the wave‐structure interaction problem. The results showed that the proposed method is reliable to estimate the external force acting on a nonlinear system.
Control of an Automotive Semi‐Active Suspension
Authors: Lozoya-Santos Jorge de Jesús , Morales-Menendez Ruben , Ramírez Mendoza Ricardo A.
Published: July 2012

Two controllers for an automotive suspensions with Magneto‐Rheological (MR) dampers are proposed. One is a model‐based using the Linear Parameter Varying (LPV) approach, and the other is a model‐free controller with a Frequency Estimation Based (FEB) principle. The LPV controller includes an experimental nonlinear model of an MR damper using only one scheduling parameter. A comparison with a several semiactive controllers for comfort and road holding is discussed. The FEB controller is the best option based on frequency and time response analysis for comfort (10–20%), suspension deflection (30–50%), and road holding (1–5%).
Comparative Analysis between SPECT Myocardial Perfusion Imaging and CT Coronary Angiography for Diagnosis of Coronary Artery Disease
Authors: Li Jian-ming , Li Ting , Shi Rong-fang , Zhang Li-ren
Published: July 2012

The study aims to discuss the relationship and difference between myocardial perfusion imaging (MPI) using SPECT and CT coronary angiography (CTCA) for diagnosis of coronary artery disease (CAD). Five hundred and four cases undergoing MPI and CTCA were comparatively analyzed, including fifty six patients undergoing invasive coronary angiography in the same period. Among patients with negative MPI results, negative or positive CTCA occupied 84.7% or 15.3%, respectively. Among patients with positive MPI, positive or negative CTCA occupied 67.2% or 32.8%, respectively. Among patients with negative CTCA, negative or positive MPI occupied 94.4% or 5.6%, respectively. Among patients with positive CTCA, positive or negative MPI occupied 40.2% or 59.8%, respectively. Negative predictive value was relatively higher than the positive predictive value for positive CTCA eliminating or predicting abnormal haemodynamics. And there was no significant difference for sensitivity, specificity, and accuracy of MPI or CTCA in diagnosing CAD. Both MPI and CTCA have good diagnostic performance for CAD. They provide different and complementary information for diagnosis and evaluation of CAD, namely, detection of ischemia versus detection of atherosclerosis, which are quite different but have a definite internal link for each other.
Unusual Forehead Tremor in Four Patients with Essential Tremor
Authors: Gascón-Bayarri Jordi , Campdelacreu Jaume , Calopa Màtil , Jaumà Serge , Bau Laura , Povedano Mònica , Montero Jordi
Published: July 2012

Forehead tremor has only been reported in two patients with essential tremor, one with rhythmic tremor and the other with dystonic tremor. We report 4 new patients with essential tremor who present a 4–6 Hz frontal tremor registered by electromyography and unusual features like frontal tremor preceding limb tremor or unilateral involvement. Frontal tremor is present in some patients with essential tremor, sometimes preceding limb tremor. Treatment with botulinum toxin may be useful.
A Graph Approach to Observability in Physical Sparse Linear Systems
Authors: Vazquez-Rodriguez Santiago , Gomollón Jesús Á. , Duro Richard J. , López Peña Fernando
Published: July 2012

A sparse linear system constitutes a valid model for a broad range of physical systems, such as electric power networks, industrial processes, control systems or traffic models. The physical magnitudes in those systems may be directly measured by means of sensor networks that, in conjunction with data obtained from contextual and boundary constraints, allow the estimation of the state of the systems. The term observability refers to the capability of estimating the state variables of a system based on the available information. In the case of linear systems, diffierent graphical approaches were developed to address this issue. In this paper a new unified graph based technique is proposed in order to determine the observability of a sparse linear physical system or, at least, a system that can be linearized after a first order derivative, using a given sensor set. A network associated to a linear equation system is introduced, which allows addressing and solving three related problems: the characterization of those cases for which algebraic and topological observability analysis return contradictory results; the characterization of a necessary and sufficient condition for topological observability; the determination of the maximum observable subsystem in case of unobservability. Two examples illustrate the developed techniques.
Periodic Wave Solutions and Their Limits for the Generalized KP‐BBM Equation
Authors: Song Ming , Liu Zhengrong
Published: July 2012

We use the bifurcation method of dynamical systems to study the periodic wave solutions and their limits for the generalized KP‐BBM equation. A number of explicit periodic wave solutions are obtained. These solutions contain smooth periodic wave solutions and periodic blow‐up solutions. Their limits contain periodic wave solutions, kink wave solutions, unbounded wave solutions, blow‐up wave solutions, and solitary wave solutions.
Metallic Stents for Proximal Tracheal Stenosis: Is It Worth the Risk?
Authors: Bansal Sandeep , Dhingra Shruti , Ghai Babita , Gupta Ashok K.
Published: July 2012

Objective. To demonstrate the risk associated with blocked proximal tracheal stents when a patient presents with acute respiratory distress, with blockage of stent and what is the best management we can offer without damage to the stent and its associated complications.Case Report. A 22-yr-old, male patient, presented in severe respiratory distress. He had history of corrosive poisoning for which he was tracheotomised. A stainless steel wire mesh stent was placed in the trachea, from the subglottis, to just above the carina. One month later, he presented with a critically compromised airway with severe respiratory distress. Emergency tracheostomy was done and the metallic stent had to be cut open, in order to provide an airway.Conclusion. Management of blocked proximal stents with patient in respiratory distress remains a challenge. Formation of granulation tissue is common and fibreoptic bronchoscopic assisted intubation may not always be possible. A regular follow up of all patients with stents is essential. Placement of stents within a few centimetres of cricotracheal junction should not be encouraged for long term indications.
Higher Ring Derivation and Intuitionistic Fuzzy Stability
Authors: Chang Ick-Soon
Published: July 2012

We take account of the stability of higher ring derivation in intuitionistic fuzzy Banach algebra associated to the Jensen type functional equation. In addition, we deal with the superstability of higher ring derivation in intuitionistic fuzzy Banach algebra with unit.
Effect of the Radial Pressure Gradient on the Secondary Flow Generated in an Annular Turbine Cascade
Authors: El-Batsh Hesham M.
Published: July 2012

This paper introduces an investigation of the effect of radial pressure gradient on the secondary flow generated in turbine cascades. Laboratory measurements were performed using an annular sector cascade which allowed the investigation using relatively small number of blades. The flow was measured upstream and downstream of the cascade using a calibrated five-hole pressure probe. The three-dimensional Reynolds Averaged Navier Stokes equations were solved to understand flow physics. Turbulence was modeled using eddy-viscosity assumption and the two-equation Shear Stress Transport (SST)k-ωmodel. The results obtained through this study showed that the secondary flow is significantly affected by the pressure gradient along blade span. The experimental measurements and the numerical calculations predicted passage vortex near blade hub which had larger and stronger values than that predicted near blade tip. The loss distribution revealed that secondary flow loss was concentrated near blade hub. It is recommended that attempts of reducing secondary flow in annular cascade should put emphasis on the passage vortex near the hub.
Mood Disorders among Older Adults Participating in Individual and Group Active Environments: “Me” versus “Us,” or Both?
Authors: Stone Rachael C. , Meisner Brad A. , Baker Joseph
Published: July 2012

Involvement in physical activity is associated with improved mental health including better social skills, coping mechanisms, and lower rates of depression. However, evidence on whether group or individual active environments better facilitate these benefits remains inconsistent. This cross-sectional cohort study examined the mental health reports of older adults (aged 50+) in relation to participation in group or individual active environments. Logistic multivariate regression analyses were conducted on the Canadian Community Health Survey (cycle 4.1, 2007-2008,n=44,057). Results illustrated that those active in both group and individual environments were 59% less likely to have a mood disorder than those who were not participating in either (P<0.001). Also, those active in both environments were 31% less likely to have a mood disorder than those active in an individual environment (P<0.001). Participating in only group or only individual environments had a similar effect compared to individuals not active in any environments for reducing rates of reported mood disorders (22% and 28%, resp.). However, the findings related to only group environments were not significant. These findings reveal that participating in both group and individual physical activities may have important implications for maintaining older adults' mental health status.
Stem Cells as a Tool for Breast Imaging
Authors: Padín-Iruegas Maria Elena , López López Rafael
Published: July 2012

Stem cells are a scientific field of interest due to their therapeutic potential. There are different groups, depending on the differentiation state. We can find lonely stem cells, but generally they distribute in niches. Stem cells don’t survive forever. They are affected for senescence. Cancer stem cells are best defined functionally, as a subpopulation of tumor cells that can enrich for tumorigenic property and can regenerate heterogeneity of the original tumor. Circulating tumor cells are cells that have detached from a primary tumor and circulate in the bloodstream. They may constitute seeds for subsequent growth of additional tumors (metastasis) in different tissues. Advances in molecular imaging have allowed a deeper understanding of the in vivo behavior of stem cells and have proven to be indispensable in preclinical and clinical studies. One of the first imaging modalities for monitoring pluripotent stem cells in vivo, magnetic resonance imaging (MRI) offers high spatial and temporal resolution to obtain detailed morphological and functional information. Advantages of radioscintigraphic techniques include their picomolar sensitivity, good tissue penetration, and translation to clinical applications. Radionuclide imaging is the sole direct labeling technique used thus far in human studies, involving both autologous bone marrow derived and peripheral stem cells.
Oscillation Theorems for Second‐Order Quasilinear Neutral Functional Differential Equations
Authors: Sun Shurong , Li Tongxing , Han Zhenlai , Li Hua
Published: July 2012

New oscillation criteria are established for the second‐order nonlinear neutral
functional differential equations of the form , t ≥ t0, where z(t) = x(t) + p(t)x(τ(t)), p ∈ C1([t0, ∞), [0, ∞)), and α ≥ 1. Our results improve and
extend some known results in the literature. Some examples are also provided to show the
importance of these results.
Discrete Model Reference Adaptive Control System for Automatic Profiling Machine
Authors: Song Peng , Xu Guo-kai , Zhao Xiu-chun
Published: July 2012

Automatic profiling machine is a movement system that has a high degree of parameter variation and high frequency of transient process, and it requires an accurate control in time. In this paper, the discrete model reference adaptive control system of automatic profiling machine is discussed. Firstly, the model of automatic profiling machine is presented according to the parameters of DC motor. Then the design of the discrete model reference adaptive control is proposed, and the control rules are proven. The results of simulation show that adaptive control system has favorable dynamic performances.