bluuebunny/crossref_metadata_2025 huggingface dataset:
Sums with convolutions of Dirichlet characters to cube-free modulus
Authors: Güloğlu Ahmet
Published: February 2011

We find estimates for short sums of the form

∑

n
m
⩽
X

χ
1

(
n
)

χ
2

(
m
)

\sum _{nm \leqslant X} \chi _1 (n) \chi _2 (m)

, where

χ
1

\chi _1

and

χ
2

\chi _2

are non-principal Dirichlet characters to modulus

q
q

, a cube-free integer, and

X
X

can be taken as small as

q

1
2

+
ϵ

q^{\frac 12+\epsilon }

.
On stability issues for IMEX schemes applied to 1D scalar hyperbolic equations with stiff reaction terms
Authors: Donat R. , Higueras I. , Martínez-Gavara A.
Published: February 2011

The application of a Method of Lines to a hyperbolic PDE with source terms gives rise to a system of ODEs containing terms that may have very different stiffness properties. In this case, Implicit-Explicit Runge-Kutta (IMEX-RK) schemes are particularly useful as high order time integrators because they allow an explicit handling of the convective terms, which can be discretized using the highly developed shock capturing technology, together with an implicit treatment of the source terms, necessary for stability reasons.

Motivated by the structure of the source term in a model problem introduced by LeVeque and Yee in [J. Comput. Phys. 86 (1990)], in this paper we study the preservation of certain invariant regions as a weak stability constraint. For the class of source terms considered in this paper, the unit interval is an invariant region for the model balance law. In the first part of the paper, we consider first order time discretizations, which are the basic building blocks of higher order IMEX-RK schemes, and study the conditions that guarantee that

[
0
,
1
]

[0,1]

is also an invariant region for the numerical scheme. In the second part of the paper, we study the conditions that ensure the preservation of this property for higher order IMEX schemes.
Approximation of the eigenvalue problem for the time harmonic Maxwell system by continuous Lagrange finite elements
Authors: Bonito Andrea , Guermond Jean-Luc
Published: February 2011

We propose and analyze an approximation technique for the Maxwell eigenvalue problem using

H

1

\mathbf {H}^1

-conforming finite elements. The key idea consists of 󠀼span style=󠀢color:black󠀢󠀾considering a mixed method󠀼/span󠀾 controlling the divergence of the electric field in a fractional Sobolev space

H

−
α

H^{-\alpha }

with

α
∈
(

1
2

,
1
)

\alpha \in (\frac 12,1)

. The method is shown to be convergent and spectrally correct.
Tissue-nonspecific alkaline phosphatase promotes axonal growth of hippocampal neurons
Authors: Díez-Zaera M. , Díaz-Hernández J. I. , Hernández-Álvarez E. , Zimmermann H. , Díaz-Hernández M. , Miras-Portugal M. T.
Published: February 2011

Axonal growth is essential for establishing neuronal circuits during brain development and for regenerative processes in the adult brain. Unfortunately, the extracellular signals controlling axonal growth are poorly understood. Here we report that a reduction in extracellular ATP levels by tissue-nonspecific alkaline phosphatase (TNAP) is essential for the development of neuritic processes by cultured hippocampal neurons. Selective blockade of TNAP activity with levamisole or specific TNAP knockdown with short hairpin RNA interference inhibited the growth and branching of principal axons, whereas addition of alkaline phosphatase (ALP) promoted axonal growth. Neither activation nor inhibition of adenosine receptors affected the axonal growth, excluding the contribution of extracellular adenosine as a potential hydrolysis product of extracellular ATP to the TNAP-mediated effects. TNAP was colocalized at axonal growth cones with ionotropic ATP receptors (P2X7receptor), whose activation inhibited axonal growth. Additional analyses suggested a close functional interrelation of TNAP and P2X7receptors whereby TNAP prevents P2X7receptor activation by hydrolyzing ATP in the immediate environment of the receptor. Furthermore inhibition of P2X7receptor reduced TNAP expression, whereas addition of ALP enhanced P2X7receptor expression. Our results demonstrate that TNAP, regulating both ligand availability and protein expression of P2X7receptor, is essential for axonal development.
The Evolutionary Genetics of Emerging Plant RNA Viruses
Authors: Elena Santiago F. , Bedhomme Stéphanie , Carrasco Purificación , Cuevas José M. , de la Iglesia Francisca , Lafforgue Guillaume , Lalić Jasna , Pròsper Àngels , Tromas Nicolas , Zwart Mark P.
Published: February 2011

Over the years, agriculture across the world has been compromised by a succession of devastating epidemics caused by new viruses that spilled over from reservoir species or by new variants of classic viruses that acquired new virulence factors or changed their epidemiological patterns. Viral emergence is usually associated with ecological change or with agronomical practices bringing together reservoirs and crop species. The complete picture is, however, much more complex, and results from an evolutionary process in which the main players are ecological factors, viruses' genetic plasticity, and host factors required for virus replication, all mixed with a good measure of stochasticity. The present review puts emergence of plant RNA viruses into the framework of evolutionary genetics, stressing that viral emergence begins with a stochastic process that involves the transmission of a preexisting viral strain into a new host species, followed by adaptation to the new host.
Preoperative Dexamethasone Enhances Quality of Recovery after Laparoscopic Cholecystectomy
Authors: Murphy Glenn S. , Szokol Joseph W. , Greenberg Steven B. , Avram Michael J. , Vender Jeffery S. , Nisman Margarita , Vaughn Jessica
Published: February 2011

Background

The effect of dexamethasone on quality of recovery after discharge from the hospital after laparoscopic surgery has not been examined rigorously in previous investigations. We hypothesized that preoperative dexamethasone would enhance patient-perceived quality of recovery on postoperative day 1 in subjects undergoing laparoscopic cholecystectomy.

Methods

One hundred twenty patients undergoing outpatient laparoscopic cholecystectomy were randomized to receive either dexamethasone (8 mg) or placebo-saline. A 40-item quality-of-recovery scoring system (QoR-40) was administered preoperatively and on postoperative day 1 to all subjects. Nausea, vomiting, fatigue, and pain scores were recorded at the time of discharge from the postanesthesia care unit and ambulatory surgical unit. Hospital length of stay was also assessed.

Results

Global QoR-40 scores on postoperative day 1 were higher in the dexamethasone group (median [range], 178 [130-195]) compared with the control group (161 [113-194]) (median difference [99% CI], -18 [-26 to -8]; P < 0.0001). Postoperative QoR-40 scores in the dimensions of emotional state, physical comfort, and pain were all improved in the dexamethasone group compared with the control group (P < 0.001). Nausea, fatigue, and pain scores were all reduced in the dexamethasone group during the hospitalization, as were postoperative analgesic requirements (P < 0.05). Total hospital length of stay was also reduced in subjects administered steroids (P = 0.003).

Conclusions

Among patients undergoing outpatient laparoscopic cholecystectomy surgery, the use of preoperative dexamethasone enhanced postdischarge quality of recovery and reduced nausea, pain, and fatigue in the early postoperative period.
Comparison of the Neuroapoptotic Properties of Equipotent Anesthetic Concentrations of Desflurane, Isoflurane, or Sevoflurane in Neonatal Mice
Authors: Istaphanous George K. , Howard Jennifer , Nan Xinyu , Hughes Elizabeth A. , McCann John C. , McAuliffe John J. , Danzer Steve C. , Loepke Andreas W.
Published: February 2011

Background

Volatile anesthetics facilitate surgical procedures and imaging studies in millions of children every year. Neuronal cell death after prolonged exposure to isoflurane in developing animals has raised serious concerns regarding its safe use in children. Although sevoflurane and desflurane are becoming more popular for pediatric anesthesia, their cytotoxic effects have not been compared with those of isoflurane. Accordingly, using newborn mice, the current study established the respective potencies of desflurane, isoflurane, and sevoflurane and then compared equipotent doses of these anesthetics regarding their effects on cortical neuroapoptosis.

Methods

Minimum alveolar concentrations were determined in littermates (aged 7-8 days, n = 42) using tail-clamp stimulation in a bracketing study design. By using equipotent doses of approximately 0.6 minimum alveolar concentration, another group of littermates was randomly assigned to receive desflurane, isoflurane, or sevoflurane or to fast in room air for 6 h. After exposure, animals (n = 47) were euthanized, neocortical apoptotic neuronal cell death was quantified, and caspase 3 activity was compared between the four groups.

Results

The minimum alveolar concentration was determined to be 12.2% for desflurane, 2.7% for isoflurane, and 5.4% for sevoflurane. After a 6-h exposure to approximately 0.6 minimum alveolar concentration of desflurane, isoflurane, or sevoflurane, neuronal cell death and apoptotic activity were significantly increased, irrespective of the specific anesthetic used.

Conclusions

In neonatal mice, equipotent doses of the three commonly used inhaled anesthetics demonstrated similar neurotoxic profiles, suggesting that developmental neurotoxicity is a common feature of all three drugs and cannot be avoided by switching to newer agents.
Spinal Macrophage Migration Inhibitory Factor Is a Major Contributor to Rodent Neuropathic Pain-like Hypersensitivity
Authors: Wang FuZhou , Xu ShiQin , Shen XiaoFeng , Guo XiRong , Peng YuZhu , Yang Jie
Published: February 2011

Background

Neuropathic pain-like hypersensitivity evoked by peripheral nerve injury is a salient clinical feature of pathologic pain; however, the underlying mechanisms of this condition remain largely unknown. Previous work has confirmed that spinal macrophage migration inhibitory factor (MIF) contributes to the pathogenesis of formalin-induced inflammatory hyperalgesia, but the role for MIF in neuropathic pain is still not well defined.

Methods

After approval by the Ethical Committee of Animal Use and Care, the sciatic chronic constriction nerve injury-induced rodent model of neuropathic pain was built. The mechanical threshold with von Frey hairs and thermal latency with hot plate were measured, and the expression of spinal MIF, CD74, and downstream extracellular signal-regulated kinase 1/2 signaling cascade was detected. Finally, MIF gene mutation and exogenous recombinant MIF were used for further clarification.

Results

Intrathecal MIF tautomerase inhibitor reversed sciatic chronic constriction nerve injury-induced pain behaviors. The expression of MIF and CD74 up-regulated in a time-dependent manner in the ipsilateral spinal cord dorsal horn. These changes were associated with the activation of extracellular signal-regulated kinase 1/2 signaling by MIF/CD74 interaction, which subsequently led to up-regulation of interleukin-8 and N-methyl-D-aspartic acid receptor expression and additional production of prostaglandin E(2). Further, MIF gene mutation and exogenous recombinant MIF could desensitize and mimic sciatic chronic constriction nerve injury-evoked pain responses and cellular changes, respectively.

Conclusions

MIF-associated extracellular signal-regulated kinase 1/2-N-methyl-D-aspartic acid receptor or prostaglandin E(2) cascade accounts for the changes in peripheral nerve injury-induced nociceptive responses.
Differential Effects of Isoflurane on High-frequency and Low-frequency γ Oscillations in the Cerebral Cortex and Hippocampus in Freely Moving Rats
Authors: Hudetz Anthony G. , Vizuete Jeannette A. , Pillay Siveshigan
Published: February 2011

Background

Cortical γ oscillations are thought to play a role in conscious cognitive functions. Suppression of 40-Hz γ activity was implicated in the loss of consciousness during general anesthesia. However, several experimental studies found that γ oscillations were preserved in anesthesia. The authors investigated the concentration-dependent effect of isoflurane on spontaneous γ oscillations in two frequency bands and three distinct brain regions in the rat.

Methods

Adult Sprague-Dawley rats were chronically implanted with epidural and coaxial depth electrodes to record cortical field potentials in frontal cortex, visual cortex, and hippocampus in waking and at steady-state isoflurane concentrations of 0.4, 0.8, and 1.2%. The γ power was calculated for the frequency bands 30-50 and 70-140 Hz. Temporal variation and interregional synchrony of γ activity were analyzed using wavelet transform. Loss of consciousness was indexed by the loss of righting reflex.

Results

Rats lost their righting reflex at 0.8 ± 0.1% isoflurane. High-frequency γ power was decreased by isoflurane in a concentration-dependent manner (P < 0.001, 50% decrease at 0.8% isoflurane) in all brain regions. Low-frequency γ power was unaffected by isoflurane. The duration and interregional synchrony of high-frequency γ bursts was also reduced (P l < 0.001, 40% decrease at 0.8% isoflurane).

Conclusions

Distinction between high- and low-frequency γ bands is important when evaluating the effect of general anesthetics on brain electrical activity. Spontaneous 40-Hz γ power does not indicate the state of consciousness. The attenuation and interregional desynchronization of high-frequency γ oscillations appear to correlate with the loss of consciousness.
Bispectral Index Monitoring, Duration of Bispectral Index Below 45, Patient Risk Factors, and Intermediate-term Mortality after Noncardiac Surgery in the B-Unaware Trial
Authors: Kertai Miklos D. , Palanca Ben J. A. , Pal Nirvik , Burnside Beth A. , Zhang Lini , Sadiq Furqaan , Finkel Kevin J. , Avidan Michael S.
Published: February 2011

Background

Postoperative mortality has been associated with cumulative anesthetic duration below an arbitrary processed electroencephalographic threshold (bispectral index [BIS] <45). This substudy of the B-Unaware Trial tested whether cumulative duration of BIS values lower than 45, cumulative anesthetic dose, comorbidities, or intraoperative events were independently associated with postoperative mortality.

Methods

The authors studied 1,473 patients (mean ± SD age, 57.9 ± 14.4 yr; 749 men) who underwent noncardiac surgery at Barnes-Jewish Hospital in St. Louis, Missouri. Multivariable Cox regression analysis was used to determine whether perioperative factors were independently associated with all-cause mortality.

Results

A total of 358 patients (24.3%) died during a follow-up of 3.2 ± 1.1 yr. There were statistically significant associations among various perioperative risk factors, including malignancy and intermediate-term mortality. BIS-monitored patients did not have lower mortality than unmonitored patients (24.9 vs. 23.7%; difference = 1.2%, 95% CI, -3.3 to 5.6%). Cumulative duration of BIS values less than 45 was not associated with mortality (multivariable hazard ratio, 1.03; 95% CI, 0.93-1.14). Increasing mean and cumulative end-tidal anesthetic concentrations were not associated with mortality. The multivariable Cox regression model showed a good discriminative ability (c-index = 0.795).

Conclusions

This study found no evidence that either cumulative BIS values below a threshold of 40 or 45 or cumulative inhalational anesthetic dose is injurious to patients. These results do not support the hypothesis that limiting depth of anesthesia either by titration to a specific BIS threshold or by limiting end-tidal volatile agent concentrations will decrease postoperative mortality.
Patient and Parent Psychosocial Factors Associated With Health‐related Quality of Life in Pediatric Inflammatory Bowel Disease
Authors: Herzer Michele , Denson Lee A , Baldassano Robert N , Hommel Kevin A
Published: February 2011

Objectives:

The aim of the study was to examine the mediating role of youth depressive symptoms in the relation between parent distress and youth health‐related quality of life (HRQOL) in a sample of adolescents with inflammatory bowel disease (IBD).

Patients and Methods:

Sixty‐two adolescents, ages 13 to 17 years, with a confirmed diagnosis of IBD completed assessments of depressive symptoms and HRQOL. Each adolescent's primary caregiver completed a measure of parent stress related to his or her child's illness. Pediatric gastroenterologists provided data for disease severity assessments.

Results:

Multiple regression analyses revealed that adolescent depressive symptoms fully mediated the relation between parent distress and several dimensions of HRQOL (ie, general well‐being, emotional functioning, social functioning, and total HRQOL). Moreover, mediation was observed after statistically controlling for the effect of disease severity, IBD diagnosis, and significant demographic parameters on HRQOL.

Conclusions:

Findings suggest that adolescent depressive symptoms may serve as the mechanism through which parent distress is linked to poorer HRQOL in adolescents with IBD. Close monitoring of parent illness‐related distress and adolescent depressive symptoms, as well as clinical interventions targeting these factors, is needed to promote optimal outcomes in adolescents with IBD.
Pediatric Inflammatory Bowel Disease and Imaging‐related Radiation: Are We Increasing the Likelihood of Malignancy?
Authors: Fuchs Yonathan , Markowitz James , Weinstein Toba , Kohn Nina , Choi‐Rosen Jeanne , Levine Jeremiah
Published: February 2011

Background and Aims:

Increasing use of diagnostic radiography has led to concern about the malignant potential of ionizing radiation. We aimed to quantify the cumulative effective dose (CED) from diagnostic medical imaging in children with inflammatory bowel disease (IBD) and to identify which children are at greatest risk for high amounts of image‐related radiation exposure.

Patients and Methods:

A retrospective chart review of pediatric IBD patients seen between January 1 and May 30, 2008 was conducted. The effective dose of radiation received from all of the radiology tests performed during the course of each patient's treatment was estimated using typical effective doses and our institution's computed tomography dose index. A CED ≥50 mSv was considered high.

Results:

Complete records were available for 257 of 372 screened subjects. One hundred seventy‐one had Crohn disease (CD) and 86 had ulcerative colitis (UC). The mean CED was 17.56 ± 15.91 mSv and was greater for children with CD than for those with UC (20.5 ± 17.5 vs 11.7 ± 9.9 mSv, P < 0.0001). Fifteen children (5.8%) had a CED ≥50 mSv, including 14 of 171 (8.2%) with CD and 1 of 86 (1.2%) with UC (P = 0.02). In children with CD, factors associated with high CED per multivariate analysis were any IBD‐related surgery (odds ratio 42, 95% confidence interval 8–223, P < 0.0001) and platelet count (odds ratio 16, 95% confidence interval 1.5–175, P = 0.02).

Conclusions:

Although all doses of ionizing radiation have some malignancy‐inducing potential, a small but important percentage of children with IBD are exposed to particularly high doses of ionizing radiation from diagnostic tests and procedures. Physicians caring for such patients must seek to limit radiation exposure whenever possible to lessen the lifetime risk of malignancy.
Nanostructured glass–ceramic coatings for orthopaedic applications
Authors: Wang Guocheng , Lu Zufu , Liu Xuanyong , Zhou Xiaming , Ding Chuanxian , Zreiqat Hala
Published: February 2011

Glass–ceramics have attracted much attention in the biomedical field, as they provide great possibilities to manipulate their properties by post-treatments, including strength, degradation rate and coefficient of thermal expansion. In this work, hardystonite (HT; Ca
2
ZnSi
2
O
7
) and sphene (SP; CaTiSiO
5
) glass–ceramic coatings with nanostructures were prepared by a plasma spray technique using conventional powders. The bonding strength and Vickers hardness for HT and SP coatings are higher than the reported values for plasma-sprayed hydroxyapatite coatings. Both types of coatings release bioactive calcium (Ca) and silicon (Si) ions into the surrounding environment. Mineralization test in cell-free culture medium showed that many mushroom-like Ca and phosphorus compounds formed on the HT coatings after 5 h, suggesting its high acellular mineralization ability. Primary human osteoblasts attach, spread and proliferate well on both types of coatings. Higher proliferation rate was observed on the HT coatings compared with the SP coatings and uncoated Ti-6Al-4V alloy, probably due to the zinc ions released from the HT coatings. Higher expression levels of Runx2, osteopontin and type I collagen were observed on both types of coatings compared with Ti-6Al-4V alloy, possibly due to the Ca and Si released from the coatings. Results of this study point to the potential use of HT and SP coatings for orthopaedic applications.
A simple DNA gate motif for synthesizing large-scale circuits
Authors: Qian Lulu , Winfree Erik
Published: February 2011

The prospects of programming molecular systems to perform complex autonomous tasks have motivated research into the design of synthetic biochemical circuits. Of particular interest to us are cell-free nucleic acid systems that exploit non-covalent hybridization and strand displacement reactions to create cascades that implement digital and analogue circuits. To date, circuits involving at most tens of gates have been demonstrated experimentally. Here, we propose a simple DNA gate architecture that appears suitable for practical synthesis of large-scale circuits involving possibly thousands of gates.
Identification and characterization of the Streptomyces globisporus 1912 regulatory gene lndYR that affects sporulation and antibiotic production
Authors: Ostash Bohdan , Rebets Yuriy , Myronovskyy Maksym , Tsypik Olga , Ostash Iryna , Kulachkovskyy Oleksandr , Datsyuk Yuriy , Nakamura Tatsunosuke , Walker Suzanne , Fedorenko Victor
Published: February 2011

Here, we report the identification and functional characterization of the Streptomyces globisporus 1912 gene lndYR, which encodes a GntR-like regulator of the YtrA subfamily. Disruption of lndYR arrested sporulation and antibiotic production in S. globisporus. The results of in vivo and in vitro studies revealed that the ABC transporter genes lndW–lndW2 are targets of LndYR repressive action. In Streptomyces coelicolor M145, lndYR overexpression caused a significant increase in the amount of extracellular actinorhodin. We suggest that lndYR controls the transcription of transport system genes in response to an as-yet-unidentified signal. Features that distinguish lndYR-based regulation from other known regulators are discussed.
Comparative analysis and mutation effects of fpp2–fpp1 tandem genes encoding proteolytic extracellular enzymes of Flavobacterium psychrophilum
Authors: Pérez-Pascual David , Gómez Esther , Álvarez Beatriz , Méndez Jessica , Reimundo Pilar , Navais Roberto , Duchaud Eric , Guijarro José A.
Published: February 2011

Flavobacterium psychrophilumis a very significant fish pathogen that secretes two biochemically characterized extracellular proteolytic enzymes, Fpp1 and Fpp2. The genes encoding these enzymes are organized as anfpp2–fpp1tandem in the genome of strainF. psychrophilumTHC02/90. Analysis of the corresponding encoded proteins showed that they belong to two different protease families. For gene function analysis, new genetic tools were developed inF. psychrophilumby constructing stable isogenicfpp1andfpp2mutants via single-crossover homologous recombination. RT-PCR analysis of wild-type and mutant strains suggested that both genes are transcribed as a single mRNA from the promoter located upstream of thefpp2gene. Phenotypic characterization of thefpp2mutant showed lack of caseinolytic activity and higher colony spreading compared with the wild-type strain. Both characteristics were recovered in the complemented strain. One objective of this work was to assess the contribution to virulence of these proteolytic enzymes. LD50experiments using the wild-type strain and mutants showed no significant differences in virulence in a rainbow trout challenge model, suggesting instead a possible nutritional role. The gene disruption procedure developed in this work, together with the knowledge of the complete genome sequence ofF. psychrophilum, open new perspectives for the study of gene function in this bacterium.
Small RNA-induced mRNA degradation achieved through both translation block and activated cleavage
Authors: Prévost Karine , Desnoyers Guillaume , Jacques Jean-François , Lavoie François , Massé Eric
Published: February 2011

Small RNA (sRNA)-induced mRNA degradation occurs through binding of an sRNA to a target mRNA with the concomitant action of the RNA degradosome, which induces an endoribonuclease E (RNase E)-dependent cleavage and degradation of the targeted mRNA. Because many sRNAs bind at the ribosome-binding site (RBS), it is possible that the resulting translation block is sufficient to promote the rapid degradation of the targeted mRNA. Contrary to this mechanism, we report here that the pairing of the sRNA RyhB to the target mRNA sodB initiates mRNA degradation even in the absence of translation on the mRNA target. Remarkably, even though it pairs at the RBS, the sRNA RyhB induces mRNA cleavage in vivo at a distal site located >350 nucleotides (nt) downstream from the RBS, ruling out local cleavage near the pairing site. Both the RNA chaperone Hfq and the RNA degradosome are required for efficient cleavage at the distal site. Thus, beyond translation initiation block, sRNA-induced mRNA cleavage requires several unexpected steps, many of which are determined by structural features of the target mRNA.
THE STEP FROM DIAGENESIS TO METAMORPHISM IN PELITIC ROCKS DURING ALPINE OROGENESIS
Authors: FREY M.
Published: February 2011

Pelitic rocks were followed from unmetamorphosed clays and marls of Upper Triassic and Lower Liassic to anchimetamorphosed phyllites of the Alpine border region in Switzerland. Phengite and Al‐rich chlorite formed from mixed‐layer illite/montmorillonite; pyrophyllite from kaolinite. For the formation of paragonite, the following sequence is proposed: irregular mixed‐layer illite/montmorillonite → regular mixed‐layer mica/montmorillonite → mixed‐layer paragonite/phengite → paragonite.

Besides the formation of new minerals in the transition zone (anchizone) between diagenesis and greenschist facies, other changes with increasing metamorphic grade are: the crystallinity of illite (in the sense of Kubler, 1967) increases, the intensity ratio 002/001 of the illite basal reflexions increases, 1Md illite changes to 2M1 phengite; the slates change colour from red to pink; the mean density increases; and textural changes due to reactions between clastic quartz and clay cement occur.
DIAGENETIC ORIGIN OF GRAYWACKE MATRIX MINERALS
Authors: WHETTEN JOHN T. , HAWKINS JAMES W.
Published: February 2011

Phyllosilicates and zeolites grew in Columbia River sediments during hydrothermal experiments at relatively low temperatures and pressures. Although the new minerals may not be equilibrium assemblages, our results strongly support the idea that matrix minerals in graywackes may be the result of alteration of components thermodynamically unstable in the environment of diagenesis. Scanning electron micrographs show that the new minerals have formed as a mesh‐like coating on original grains. The textural relationship of the new minerals to the original minerals resembles graywacke texture.
PTEN in colorectal cancer: a report on two Cowden syndrome patients
Authors: Kersseboom R , Dubbink HJ , Corver WE , van Tilburg AJP , Poley JW , van Leerdam ME , Atmodimedjo PN , van de Laar IMBH , Collée JM , Dinjens WNM , Morreau H , Wagner A
Published: February 2011

Kersseboom R, Dubbink HJ, Corver WE, van Tilburg AJP, Poley JW, van Leerdam ME, Atmodimedjo PN, van de Laar IMBH, Collée JM, Dinjens WNM, Morreau H, Wagner A. PTEN in colorectal cancer; a report on two Cowden syndrome patients.

Heterozygous germline PTEN mutations cause Cowden syndrome. The risk of colorectal cancer in Cowden patients, however, remains a matter of debate. We describe two patients presenting with colorectal cancer at a young age (28 and 39 years) and dysmorphisms fitting the Cowden spectrum. Heterozygous germline mutations in PTEN were found in both patients. Moreover, analysis of the resected colorectal cancer specimens revealed loss of heterozygosity at the PTEN locus with retention of the mutated alleles, and greatly reduced or absent PTEN expression. Histologically and molecularly, the tumours showed resemblance with sporadic colorectal cancers, although they had prominent fibrotic stroma. Our data indicate that PTEN loss was involved in carcinogenesis in the two patients, supporting that colorectal cancer is part of the Cowden syndrome‐spectrum. This is in line with data on sporadic colorectal cancer, mice studies and emerging epidemiological data on Cowden syndrome. Although the exact role of germline PTEN mutations in the carcinogenesis of colorectal cancer remains unclear, we think that Cowden syndrome should be in the differential diagnosis of colorectal cancer certainly in view of the possible prognostic and therapeutic consequences. Prospective follow‐up and surveillance of PTEN mutation carriers from the age of 25 to 30 years in a study setting should clarify this issue.
Exome sequencing expedites disease gene discovery
Authors: Huang K
Published: February 2011

Exome sequencing identifies ACAD9 mutations as a cause of complex I deficiency

Haack et al. (2010)

Nature Genetics 42:1131‐1134
Magnetic field protects plants against high light by slowing down production of singlet oxygen
Authors: Hakala‐Yatkin Marja , Sarvikas Päivi , Paturi Petriina , Mäntysaari Mika , Mattila Heta , Tyystjärvi Taina , Nedbal Ladislav , Tyystjärvi Esa
Published: February 2011

Recombination of the primary radical pair of photosystem II (PSII) of photosynthesis may produce the triplet state of the primary donor of PSII. Triplet formation is potentially harmful because chlorophyll triplets can react with molecular oxygen to produce the reactive singlet oxygen (1O2). The yield of 1O2 is expected to be directly proportional to the triplet yield and the triplet yield of charge recombination can be lowered with a magnetic field of 100–300 mT. In this study, we illuminated intact pumpkin leaves with strong light in the presence and absence of a magnetic field and found that the magnetic field protects against photoinhibition of PSII. The result suggests that radical pair recombination is responsible for significant part of 1O2 production in the chloroplast. The magnetic field effect vanished if leaves were illuminated in the presence of lincomycin, an inhibitor of chloroplast protein synthesis, or if isolated thylakoid membranes were exposed to light. These data, in turn, indicate that 1O2 produced by the recombination of the primary charge pair is not directly involved in photoinactivation of PSII but instead damages PSII by inhibiting the repair of photoinhibited PSII. We also found that an Arabidopsis thaliana mutant lacking α‐tocopherol, a scavenger of 1O2, is more sensitive to photoinhibition than the wild‐type in the absence but not in the presence of lincomycin, confirming that the target of 1O2 is the repair mechanism.
The Effects of the Fast Track Preventive Intervention on the Development of Conduct Disorder Across Childhood
Authors:   Conduct Problems Prevention Research Group
Published: February 2011

The impact of the Fast Track intervention on externalizing disorders across childhood was examined. Eight hundred‐ninety‐one early‐starting children (69% male; 51% African American) were randomly assigned by matched sets of schools to intervention or control conditions. The 10‐year intervention addressed parent behavior‐management, child social cognitive skills, reading, home visiting, mentoring, and classroom curricula. Outcomes included psychiatric diagnoses after grades 3, 6, 9, and 12 for conduct disorder, oppositional defiant disorder, attention deficit hyperactivity disorder, and any externalizing disorder. Significant interaction effects between intervention and initial risk level indicated that intervention prevented the lifetime prevalence of all diagnoses, but only among those at highest initial risk, suggesting that targeted intervention can prevent externalizing disorders to promote the raising of healthy children.
Criminalization and Deviantization as Properties of the Social Order
Authors: Ben-Yehuda Nachman
Published: February 2011

It is argued that deviance should be analyzed as a relative phenomenon in different and changing cultures, vis-a-vis change and stability in the boundaries of diverse symbolic-moral universes. Deviantization and criminalization are interpreted as the outcomes of negotiations about the nature of morality and legitimization to use, and the use of, power.

The legitimization of power is conceptualized in terms of a moral order that in turn defines the boundaries of symbolic-moral universes. Problematic behavioural acts, which take place at the realm of the seams, where boundaries of different symbolic-moral universes meet and touch, or which are directed from the periphery of a symbolic-moral universe towards its centre and vice versa, and which involve challenges (use or abuse) of power and morality would fall in the area of deviance.

A distinction is made between regular deviance where the element of power is typically implicit and the element of morality is much more salient, and political deviance where the elements of power and morality are both explicit. Political deviance is further divided into three categories: challenges to the rulers, challenges from the rulers and contests between symbolic-moral universes from different cultures. Conceptualizing deviance in this way enables us to interpret processes of deviantization and criminalization within the context of central social processes.

The November 1944 assassination of Lord Moyne is used to demonstrate how the above theoretical approach can be utilized to develop a sociological interpretation of the case.
Professionals' and Parents' Perceptions of A&E Use in a Children's Hospital
Authors: Roberts Helen
Published: February 2011

Helpful keywords in accessing literature on the use made of hospital accident and emergency (A&E) departments are ‘misuse’ ‘abuse’ and ‘inappropriate’.

While the medical literature is inclined to present patients (and, in the case of children, their parents) as irresponsible, or misguided, social scientists looking at similar data have tended to act as apologists for patients, explaining A&E attendance in terms of poor access to GPs, mistaken beliefs about the relative skills of hospital-based doctors and GPs and ‘lay’ health beliefs. Both of these approaches see the patient (or parent) as passive recipients of health care, rather than active caretakers of their own or their children's health.

On the basis of a study of minor ailments presenting at a children's A&E department, this paper explores the differing views of health workers and parents. It suggests that a view of patients (parents) as largely passive custodians of their own or their children's health is inadequate. Patients (parents) can and do play an active part as providers of primary health care and their decisions to use A&E are not as irrational as health providers sometimes suppose. In this light, attempts to ‘re-educate’ parents to use A&E in a way which would be more acceptable to health providers is unlikely to succeed.
Global vegetation and terrestrial carbon cycle changes after the last ice age
Authors: Prentice I. C. , Harrison S. P. , Bartlein P. J.
Published: February 2011

Featured paper: See also the Editorial by Norby
Soil organic carbon fractions and management index after 20 yr of manure and fertilizer application for greenhouse vegetables
Authors: Lou Y. , Xu M. , Wang W. , Sun X. , Liang C.
Published: February 2011

Impacts of organic manure and inorganic fertilizer on total organic carbon (CT), water‐soluble organic C (CWS), microbial biomass C (CMB), particulate organic C (CP), labile organic C (CL), C storage and sequestration, and C management index (CMI) in surface soil (0–20 cm) were investigated in a 20‐yr field experiment under a greenhouse vegetable system in northeast China. The treatments included unfertilized control (CK), N fertilizer (N), balanced NPK fertilizer (NPK), organic manure alone (M) and the NPK fertilizer combined with the manure (MNPK). Under the treatments of N and NPK, CT content and C storage were not significantly changed over the experimental period, while CWS, CMB, CP, CL concentrations and CMI were significantly increased compared with the unfertilized control. In comparison with the control, the manure treatments, M and MNPK, significantly increased CT content and C storage, sequestrating organic C of 8.9 and 9.2 Mg/ha, respectively. The M and MNPK treatments showed higher CWS, CMB, CP and CL concentrations and CMI than the other three treatments. Pearson’s correlation coefficients were used to show that CWS, CMB, CP, CL and CMI could be useful indicators for assessing soil quality and total C changes. The M treatment is effective in sequestrating soil C, but resulted in lower crop yield compared with the NPK treatment. The MNPK treatment showed the greatest increases in crop yield and C sequestration in the greenhouse vegetable system.
Google's Insights for Search: A Note Evaluating the Use of Search Engine Data in Social Research*
Authors: Scheitle Christopher P.
Published: February 2011

Objective. This research note presents and assesses the potential for Google's Insights for Search tool for use in social science research.

Methods. Measures of social phenomena across time and across ecological units produced from search engine data are compared with existing data sources.

Results. The comparisons show that the search engine data correspond quite closely with existing measures of issue salience and religious adherence.

Conclusions. Given its relative lack of cost both in terms of money and labor, its flexibility, and its correspondence to other data, social scientists should consider the Insights for Search tool for research purposes.
Ordinary states: Everyday corruption and the politics of space in Mumbai
Authors: ANJARIA JONATHAN SHAPIRO
Published: February 2011

In this article, I draw from fieldwork on the micropractices of hawkers’ illicit dealings with low‐level state functionaries in Mumbai, India, to explore how claims to city space are negotiated. I argue that what is often understood as a breakdown in urban governance is, instead, what I call an “ordinary space of negotiation” that constitutes the grounds on which claims to substantive citizenship are made. This ethnographic exploration of what practices of corruption produce has the possibility to expand how scholars think about the state and political claim making in liberal democratic contexts at large.
Characterization of a maternal–fetal HIV transmission model using pregnant macaques infected with HIV‐2287
Authors: Ho R.J.Y. , Larsen K. , Kinman L. , Sherbert C. , Wang X.Y. , Finn E. , Nosbisch C. , Schmidt A. , Anderson D. , Hu S.L. , Agy M. , Ochs H. , Morton W.R. , Unadkat J.D.
Published: February 2011

Abstract: To study mechanisms involved in mother‐to‐fetus transmission of human immunodeficiency virus (HIV) in utero, we have developed a chronically catheterized pregnant macaque model that permits simultaneous and sequential determination of virus in maternal and fetal blood and amniotic fluid during pregnancy. In this report, we have characterized this model using three groups of pregnant macaques designed to sample: (1) maternal blood, fetal blood, and amniotic fluid (n = 6); (2) maternal blood and amniotic fluid (n = 6); or (3) maternal blood only (n = 2). After inoculation with the highly pathogenic HIV‐2287, all pregnant macaques developed brief but intense viremias followed by precipitous CD4+ T‐cell declines within 2–3 weeks. While all the infants born to dams of the three groups were HIV positive, the degree of infection and outcome of HIV infection varied. All infants were shown to be HIV‐RNA‐positive by reverse transcriptase‐polymerase chain reaction (RT‐PCR). However, HIV‐infected cells were detected only in the blood of those born to dams enrolled in groups 1 and 2: most of these infants progressed to CD4+ T‐cell depletion. The infants in group 3 exhibited HIV‐RNA in plasma, although neither HIV‐infected cells nor CD4+ T‐cell depletion was detectable. However, all infants developed HIV‐2‐specific antibody at various levels by 2 months of age. Together, the data suggest that, while the degree of instrumentation may modulate intensity of virus transmission to fetus, the highly pathogenic HIV‐2287 exhibited a high frequency of virus transmission from the mother to fetus.
The Consumer Life Cycle
Authors: STAMPFL RONALD W.
Published: February 2011

The field of consumer education needs conceptual frameworks to organize the growing body of existing knowledge and to point to needed research. The use of the familiar life cycle variable for this purpose is proposed. Generalizations, based upon a review of the literature, are offered about the characteristics, typical product and service purchases, marketplace concepts and knowledge, marketplace skills, typical marketplace problems and level of resources of different life cycle stage categories.
The Economic Effects of Repealing Fair Trade Laws
Authors: SHEPARD LAWRENCE
Published: February 2011

Legislation in 1976 abolishing fair trade appears to have led to limited price cutting among retailers. In particular, stores identified by their managers as being “discount” outlets were found to have undercut the prices of other stores in most product groups while the pricing policies of chain stores and multi‐line stores have not become more aggressive on fair trade items since repeal. Limited evidence indicates that a reduction in nonprice competition in the form of newspaper advertising and sales personnel has also attended repeal. Finally, a substantial increase in the frequency of business failures in fair trade states during 1976 indicates that a consolidation among retailers may have coincided with the abolishment of uniform, manufacturer‐specified retail prices.
MALNUTRITION‐INFLAMMATION‐ATHEROSCLEROSIS SYNDROME IN PATIENTS WITH END‐STAGE RENAL DISEASE
Authors: Zyga Sofia , Christopoulou Georgia , Malliarou Maria
Published: February 2011

Malnutrition‐inflammation‐atherosclerosis (MIA) syndrome is where three dominant clinical entities which occur in patients with end‐stage renal disease—malnutrition, inflammation and atherosclerosis—coexist and interact with each other. This literature review aims to present the factors which are responsible for the existence of MIA syndrome in patients with end‐stage chronic kidney disease (CKD) on renal replacement therapy. Studies have shown that the main role in the pathogenesis of the MIA syndrome is played by inflammatory cytokines. The main inflammatory cytokines are tumour necrosis factor‐a, interleukin‐1 and interleukin‐6. The following work examines these cytokines, indicating their main characteristics and the basic mode of action in patients with end‐stage CKD as well as the further development of the syndrome. The existence of this syndrome is responsible for the high rates of morbidity and mortality in this group of patients who reach a level comparable with persons suffering from metastatic cancer.
THE EVOLUTION OF THE NEPHROLOGY EDUCATORS’ NETWORK
Authors: Sinclair Peter M. , Levett‐Jones Tracy
Published: February 2011

Nephrology nurse educators face many challenges related to professional development and resource sharing. In Australia and New Zealand, as well as other countries where the ‘tyranny of distance’ is a feature, access, equity and lack of educational support due to the geographical isolation of many nephrology units, present particular challenges. This paper reports the findings from a case study of 51 nephrology nurse educators in Australia. Using an exploratory descriptive approach, the study aimed to identify current issues facing nephrology nurse educators and determine the feasibility of developing an online community of practice to support them in their role. An outcome of the study was the establishment of The Nephrology Educators’ Network. This network seeks to enhance peer support, collegiality, critical companionship, collaboration, knowledge sharing and the benchmarking of practices for those involved in nephrology nurse education. In this paper, we describe and reflect on some of the outcomes and challenges faced in developing this network.
Diagenetic and Mineralization Age of the Hehuaping Tin‐polymetallic Orefield, Hunan Province
Authors: Daofang WEI , Zhengyu BAO , Jianming FU , Minghai CAI
Published: February 2011

Abstract: The Hehuaping tin deposit is a large deposit found in recent years during geological surveys. The discovered tin deposit includes not only rock‐alteration type deposits in fault zones, but also deposits developed in interstratifled rupture zones between Devonian carbonate rocks (Qiziqiao Formation) and sandstone (Tiaomajian Formation). The finding of tin deposits of the latter type has greatly enriched tin‐mineralization types in the famous Nanling polymetallic metallogenetic region and may provide us with a new potential orientation for prospecting of tin deposits in the region. It is commonly believed that the forming of the tin deposits in the Nanling region should be related to the Yanshanian instead of Indosinian granitic magmatism. Systematical zircon U‐Pb SHRIMP dating in this paper shows that tin mineralizations have endured at least two stages. The early stage should be related to the intrusion of the main body of the Wangxianling granite, which was emplaced during the Indosinian period with a diagenetic and mineralized age of 224.0±1.9 Ma (MSWD=0.54), and the late stage should be related to the intrusion of Yanshanian granitic porphyry that took place after 142±3 Ma (MSWD=0.5).