bluuebunny/crossref_metadata_2025 huggingface dataset:
Gln27→Gluβ2‐Adrenergic Receptor Polymorphism in Heart Failure Patients: Differential Clinical and Oxidative Response to Carvedilol
Authors: Troncoso Rodrigo , Moraga Francisco , Chiong Mario , Roldán Juan , Bravo Roberto , Valenzuela Rodrigo , Díaz‐Araya Guillermo , Del Campo Andrea , Sanhueza Carlos , Rodriguez Andrea , Vukasovic José Luis , Mellado Rosemarie , Greig Douglas , Castro Pablo F. , Lavandero Sergio
Published: January 2009

Abstract: We investigated the clinical response of chronic heart failure patients with β2‐adrenergic receptor Gln27→Glu polymorphism treated for 6 months with carvedilol, a α/β‐antagonist with antioxidant properties. The 6‐min. walk test, the left ventricular ejection fraction, heart rate, plasma norepinephrine and malondialdehyde, a stress oxidative marker, concentrations were evaluated at baseline and after treatment for 6 months with carvedilol in 33 stable chronic heart failure patients with the Gln27→Gluβ2‐adrenergic receptor polymorphism. Carvedilol significantly increased the left ventricular ejection fraction, while decreasing the heart rate and malondialdehyde plasma concentrations in chronic heart failure patients with the Glu27β2‐adrenergic receptor allele. There were however, no significant changes in patients with the Gln27β2‐adrenergic receptor variant.
Overexpression of a New Putative Membrane Protein Gene AtMRB1 Results in Organ Size Enlargement in Arabidopsis
Authors: Guan Hua , Kang Dingming , Fan Min , Chen Zhangliang , Qu Li‐Jia
Published: January 2009

Arabidopsis AtMRB1 is predicted to encode a novel protein of 432 amino acid residues in length, with four putative trans‐membrane domains. In the present study, characterization of AtMRB1 is conducted. Green fluorescent protein (GFP) fusion protein assay showed that AtMRB1 was located in the plasma membrane. Transgenic lines overexpressing AtMRB1 driven by a CaMV 35S promoter were generated. Statistic analysis showed that, during the seedling stage, the organ sizes of the transgenic lines including hypocotyl length, root length and root weight were significantly larger than those of the wild type plants under both light and dark conditions. In the adult plant stage, the AtMRB1 overexpressor plants were found to have larger organ sizes in terms of leaf length and width, and increased number of cauline leaves and branches when bolting. Further observation indicated that the larger leaf size phenotype was due to a larger number of mesophyll cells, the size of which was not altered. Quantitative real‐time polymerase chain reaction analysis showed that the transcription of ANT, ROT3 and GRF5 were upregulated in the AtMRB1‐overexpressor plants. These data suggest that AtMRB1 is possibly a positive regulator of organ size development in Arabidopsis, mainly through cell number control.
Coaching patients to self‐care: a primary responsibility of nursing
Authors: Pryor Julie
Published: January 2009

Aim.  To explore the process nurses use to guide and support patients to actively re‐establish self‐care.

Background.  The movement of hospitalized patients from less to more independence is primarily a nursing responsibility. Studies of nursing practice in inpatient rehabilitation settings have begun to shed some light on this, but as yet there is limited understanding of the actual skills nurses use to support patients to re‐establish self‐care.

Method.  This study used grounded theory. Microanalysis and constant comparative analysis of data collected during interviews with, and observation of, registered and enrolled nurses during everyday nursing practice in five inpatient rehabilitation units facilitated open, axial and selective coding. Relevant literature was woven into the final theory.

Findings.  To facilitate patient transition from the role of acute care patient to rehabilitation patient actively reclaiming self‐care, nurses engaged in a three‐phase process known as coaching patients to self‐care. The three phases were: easing patients into rehabilitation, maximizing patient effort and providing graduated assistance.

Conclusion.  Coaching patients to self‐care is a primary activity and technology of rehabilitation nursing.

Relevance to clinical practice.  Patients in a variety of settings would benefit from nurses incorporating coaching skills into their nurse–patient interactions.
Impact of Copper Sulfate on Plankton in Channel Catfish Nursery Ponds
Authors: Mischke Charles C. , Wise David J. , Zimba Paul V.
Published: January 2009

Many fish culturists are interested in applying copper sulfate pentahydrate (CSP) to channel catfish, Ictalurus punctatus, nursery ponds as a prophylactic treatment for trematode infection and proliferative gill disease by killing snails and Dero sp., respectively, before stocking fry. However, copper is an algaecide and may adversely affect phytoplankton and zooplankton populations. We evaluated the effects of prophylactic use of copper sulfate in catfish nursery ponds on water quality and phytoplankton and zooplankton populations. In 2006, treatments of 0 mg/L CSP, 3 mg/L CSP (0.77 mg/L Cu), and 6 mg/L CSP (1.54 mg/L Cu) were randomly assigned to 0.04‐ha ponds. In 2007, only treatments of 0 and 3 mg/L CSP were randomly assigned to the 16 ponds. Ponds treated with CSP had significantly higher pH and significantly lower total ammonia concentrations. Treatment of both CSP rates increased total algal concentrations but reduced desirable zooplankton groups for catfish culture. CSP has been shown to be effective in reducing snail populations at the rate used in this study. CSP treatment also appears to be beneficial to the algal bloom, shifting the algal population to green algae and increasing total algal biomass within 1 wk after CSP treatment. Although zooplankton populations were adversely affected, populations of important zooplankton to catfish fry began rebounding 6–12 d after CSP treatment. Therefore, if CSP is used to treat catfish fry ponds of similar water composition used in this study, fry should not be stocked for about 2 wk after CSP application to allow time for the desirable zooplankton densities to begin increasing.
Isolation and characterization of 12 dinucletiotide microsatellite loci in Paratrechalea galianoae (Araneae, Trechaleidae), a nuptial gift‐spider
Authors: DA SILVEIRA LUCAS CAETANO TIEPPO , BONATTO SANDRO L.
Published: January 2009

Twelve microsatellite loci from the Neotropical spider Paratrechalea galianoae were isolated from a microsatellite‐enriched genomic library, and were tested in a sample of 27 individuals from a population that occurs in Brazil. All loci were polymorphic and three to 14 (mean 7.58) alleles per locus were identified. The observed and expected heterozygosities per locus ranged from 0.417 to 0.885 and from 0.595 to 0.878, respectively. Two loci deviated significantly from Hardy–Weinberg equilibrium and one pair showed evidence of linkage disequilibrium. These loci are being used to study the population structure and genetic diversity in P. galianoae.
Consequences of axon guidance defects on the development of retinotopic receptive fields in the mouse colliculus
Authors: Chandrasekaran Anand R. , Furuta Yas , Crair Michael C.
Published: January 2009

Gradients of molecular factors pattern the developing retina and superior colliculus (SC) and guide retinal ganglion cell (RGC) axons to their appropriate central target perinatally. During and subsequent to this period, spontaneous waves of action potentials sweep across the retina, providing an instructive topographic signal based on the correlations of firing patterns of neighbouring RGCs. How these activity‐independent and activity‐dependent factors interact during retinotopic map formation remains unclear. A typical phenotype of mutant mice lacking genes for one or more RGC axon guidance molecules is the presence of topographically inappropriate projections or ‘ectopic spots’. Here, we examine mice that lack functional bone morphogenetic protein receptors (BMPRs) in the retina. Retinal BMP controls the graded expression of RGC axon guidance molecules, resulting in some dorsal RGCs projecting ectopically to locations in the SC that normally receive input from ventral retina. We examine the consequences of this anatomical phenotype in vivo by studying the receptive field (RF) properties of neurons in the superficial SC. We observe a mixture of physiological phenotypes in BMPR mutant mice; notably we find some neurons with ectopic RFs displaced in elevation, corresponding to the observed anatomical defect. However, in a result not necessarily congruent with the presence of focal ectopic projections, some neurons have split, enlarged and patchy/distorted RFs. These results are consistent with the effects of spontaneous retinal waves acting upon a disrupted molecular template, and they place significant limits on the form of an activity‐dependent learning rule for the development of retinocollicular projections.
Excitation–contraction coupling gain in ventricular myocytes: insights from a parsimonious model
Authors: Sobie Eric A. , Ramay Hena R.
Published: January 2009

We present a minimal mathematical model of Ca2+ spark triggering under voltage‐clamp conditions in ventricular myocytes. The model predicts changes in excitation–contraction coupling ‘gain’ that result from diverse experimental interventions. We compare model results to several sets of data, and, in so doing, place apparent constraints on physiologically relevant model parameters. Specifically, the analysis suggests that many L‐type Ca2+ channel openings can potentially trigger each Ca2+ spark, but the probability that an individual opening will trigger a spark is low. This procedure helps to reconcile contradictory results obtained in recent studies; moreover, this new model should be a useful tool for understanding changes in gain that occur physiologically and in disease.
Voltage‐dependent and ‐independent titration of specific residues accounts for complex gating of a ClC chloride channel by extracellular protons
Authors: Niemeyer María Isabel , Cid L. Pablo , Yusef Yamil R. , Briones Rodolfo , Sepúlveda Francisco V.
Published: January 2009

The ClC transport protein family comprises both Cl− ion channel and H+/Cl− and H+/NO3− exchanger members. Structural studies on a bacterial ClC transporter reveal a pore obstructed at its external opening by a glutamate side‐chain which acts as a gate for Cl− passage and in addition serves as a staging post for H+ exchange. This same conserved glutamate acts as a gate to regulate Cl− flow in ClC channels. The activity of ClC‐2, a genuine Cl− channel, has a biphasic response to extracellular pH with activation by moderate acidification followed by abrupt channel closure at pH values lower than ∼7. We have now investigated the molecular basis of this complex gating behaviour. First, we identify a sensor that couples extracellular acidification to complete closure of the channel. This is extracellularly‐facing histidine 532 at the N‐terminus of transmembrane helix Q whose neutralisation leads to channel closure in a cooperative manner. We go on to show that acidification‐dependent activation of ClC‐2 is voltage dependent and probably mediated by protonation of pore gate glutamate 207. Intracellular Cl− acts as a voltage‐independent modulator, as though regulating the pKa of the protonatable residue. Our results suggest that voltage dependence of ClC‐2 is given by hyperpolarisation‐dependent penetration of protons from the extracellular side to neutralise the glutamate gate deep within the channel, which allows Cl− efflux. This is reminiscent of a partial exchanger cycle, suggesting that the ClC‐2 channel evolved from its transporter counterparts.
Defining the role of GABA in cortical development
Authors: Wang Doris D. , Kriegstein Arnold R.
Published: January 2009

Of the many signals in the developing nervous system, GABA (γ‐aminobutyric acid) has been shown to be one of the earliest neurotransmitters present. Unlike in the adult, where this transmitter acts synaptically to inhibit neurons, during development, GABA can depolarize progenitor cells and their progeny due to their high intracellular chloride concentration. This early form of GABA signalling may provide the main excitatory drive for the immature cortical network and play a central role in regulating cortical development. Many features of GABA signalling are conserved in different species and are recapitulated during neurogenesis in the adult brain, demonstrating the importance of this versatile molecule in driving cortical formation. Here, we present recent evidence supporting the multiple functions of GABA during embryonic development and adult neurogenesis, from regulating progenitor proliferation to influencing the migration and maturation of newborn neurons.
Regulatory T Cells Promote Early Influx of CD8+T Cells in the Lungs of Respiratory Syncytial Virus-Infected Mice and Diminish Immunodominance Disparities
Authors: Ruckwardt Tracy J. , Bonaparte Kathryn L. , Nason Martha C. , Graham Barney S.
Published: January 2009

In addition to regulating autoimmunity and antitumor immunity, CD4+CD25+FoxP3+natural regulatory T (Treg) cells are global regulators of adaptive immune responses. Depletion of these cells with the anti-CD25 antibody PC61 prior to primary respiratory syncytial virus (RSV) infection was partial but had several effects on the RSV-specific CD8+response in a hybrid mouse model. Mediastinal lymph node and spleen epitope-specific CD8+T-cell responses were enhanced in Treg-cell-depleted mice at all time points following infection, but responses of Treg-cell-depleted lung show a strikingly different pattern than lymphoid organ responses, with an initial delay in the CD8+T-cell response. The delay in the CD8+T-cell response correlated with a delay both in the early phase of viral clearance and in illness in Treg-cell-depleted mice compared to isotype-treated controls. The lungs of Treg-cell-depleted mice were shown to have increased lung chemokine and cytokine levels 7 days postinfection despite lower CD8+T-cell responses. Following the early delay in the lung response, CD8+T-cell responses at later infection time points were enhanced and increased the severity of illness in depleted mice. Finally, decreasing regulatory T-cell control of the CD8+T-cell response had a greater effect on response of the dominant Kd-restricted M2 epitope consisting of amino acids 82 to 90 (KdM282-90) than on the subdominant DbM187-195epitope response, indicating that regulatory T cells modulate immunodominance disparities in epitope-specific CD8+T-cell responses following primary RSV infection.
Biarsenical Labeling of Vesicular Stomatitis Virus Encoding Tetracysteine-Tagged M Protein Allows Dynamic Imaging of M Protein and Virus Uncoating in Infected Cells
Authors: Das Subash C. , Panda Debasis , Nayak Debasis , Pattnaik Asit K.
Published: January 2009

A recombinant vesicular stomatitis virus (VSV-PeGFP-M-MmRFP) encoding enhanced green fluorescent protein fused in frame with P (PeGFP) in place of P and a fusion matrix protein (monomeric red fluorescent protein fused in frame at the carboxy terminus of M [MmRFP]) at the G-L gene junction, in addition to wild-type (wt) M protein in its normal location, was recovered, but the MmRFP was not incorporated into the virions. Subsequently, we generated recombinant viruses (VSV-PeGFP-ΔM-Mtc and VSV-ΔM-Mtc) encoding M protein with a carboxy-terminal tetracysteine tag (Mtc) in place of the M protein. These recombinant viruses incorporated Mtc at levels similar to M in wt VSV, demonstrating recovery of infectious rhabdoviruses encoding and incorporating a tagged M protein. Virions released from cells infected with VSV-PeGFP-ΔM-Mtc and labeled with the biarsenical red dye (ReAsH) were dually fluorescent, fluorescing green due to incorporation of PeGFP in the nucleocapsids and red due to incorporation of ReAsH-labeled Mtc in the viral envelope. Transport and subsequent association of M protein with the plasma membrane were shown to be independent of microtubules. Sequential labeling of VSV-ΔM-Mtc-infected cells with the biarsenical dyes ReAsH and FlAsH (green) revealed that newly synthesized M protein reaches the plasma membrane in less than 30 min and continues to accumulate there for up to 2 1/2 hours. Using dually fluorescent VSV, we determined that following adsorption at the plasma membrane, the time taken by one-half of the virus particles to enter cells and to uncoat their nucleocapsids in the cytoplasm is approximately 28 min.
Are Human P[14] Rotavirus Strains the Result of Interspecies Transmissions from Sheep or Other Ungulates That Belong to the Mammalian Order
Artiodactyla
?
Authors: Matthijnssens Jelle , Potgieter Christiaan A. , Ciarlet Max , Parreño Viviana , Martella Vito , Bányai Krisztián , Garaicoechea Lorena , Palombo Enzo A. , Novo Luis , Zeller Mark , Arista Serenella , Gerna Giuseppe , Rahman Mustafizur , Van Ranst Marc
Published: January 2009

A limited number of human G6P[14] rotavirus strains that cause gastroenteritis in humans have been isolated in Europe and Australia. The complete genome sequences were determined for five of these human strains—B10925-97 (isolated in Belgium in 1997), 111/05-27 (Italy, 2005), PA169 (Italy, 1987), MG6 (Australia, 1993), and Hun5 (Hungary, 1997)—and their genetic relatedness to animal rotavirus strains was evaluated by sequencing the complete genome of the sheep rotavirus OVR762 (G8P[14]; Spain, 2002), the guanaco (
Lama guanicoe
) rotavirus strains Arg/Chubut/99 and Arg/Río Negro/98 (G8P[14] and G8P[1], respectively; Argentina, 1999 and 1998), the sable antelope strain RC-18/08 (G6P[14]; South Africa, 2008), and the bovine rotavirus strain Arg/B383/98 (G15P[11]; Argentina, 1998). These analyses revealed an overall consensus genomic constellation (G6/G8)-P[14]-I2-(R2/R5)-C2-M2-(A3/A11)-N2-T6-(E2/E12)-H3, together with a few gene reassortments, and the phylogenetic analyses confirmed that the P[14] human strains evaluated in this study were closely related to rotavirus strains isolated from sheep, cattle, goats, guanacos, and antelopes and to rabbits (albeit to a lesser extent), suggesting that one (or more) of these animal species might be the source of the human G6P[14] strains. The main feature of the genotype and phylogenetic analyses was the close overall genomic relatedness between the five human G6P[14] rotavirus strains and the ovine and antelope rotavirus strains. Taken together, these data strongly suggest a common origin for the human P[14] strains and those of the even-toed ungulates belonging to the mammalian order
Artiodactyla
, with sheep probably playing a key role in the interspecies transmission responsible for the introduction of P[14] rotavirus strains into the human population.
The Major Portal of Entry of Koi Herpesvirus in
Cyprinus carpio
Is the Skin
Authors: Costes B. , Raj V. Stalin , Michel B. , Fournier G. , Thirion M. , Gillet L. , Mast J. , Lieffrig F. , Bremont M. , Vanderplasschen A.
Published: January 2009

Koi herpesvirus (KHV), recently designated
Cyprinid herpesvirus 3
, is the causative agent of a lethal disease in koi and common carp. In the present study, we investigated the portal of entry of KHV in carp by using bioluminescence imaging. Taking advantage of the recent cloning of the KHV genome as a bacterial artificial chromosome (BAC), we produced a recombinant plasmid encoding a firefly luciferase (LUC) expression cassette inserted in the intergenic region between open reading frame (ORF) 136 and ORF 137. Two viral strains were then reconstituted from the modified plasmid, the FL BAC 136 LUC excised strain and the FL BAC 136 LUC TK revertant strain, including a disrupted and a wild-type thymidine kinase (TK) locus, respectively. In vitro, the two recombinant strains replicated comparably to the parental FL strain. The FL BAC 136 LUC TK revertant strain was shown in vitro to induce a bioluminescent signal allowing the detection of single positive cells as early as 24 h postinfection, while in vivo, it induced KHV infection in carp that was indistinguishable from that induced by the parental FL strain. To identify the KHV portal of entry, carp were analyzed by bioluminescence imaging at different times postinfection with the FL BAC 136 LUC TK revertant strain. These analyses demonstrated that the skin of the fish covering the fins and also the body is the major portal of entry for KHV in carp. Finally, to further demonstrate the role of the skin as the KHV portal of entry, we constructed an original system, nicknamed “U-tube,” to perform percutaneous infection restricted to the posterior part of the fish. All the data obtained in the present study demonstrate that the skin, and not the gills, is the major portal of entry for KHV in carp.
A Key Role for Heat Shock Protein 70 in the Localization and Insertion of Tombusvirus Replication Proteins to Intracellular Membranes
Authors: Wang Robert Yung-Liang , Stork Jozsef , Nagy Peter D.
Published: January 2009

Plus-stranded RNA viruses coopt host proteins to promote their robust replication in infected hosts.
Tomato bushy stunt tombusvirus
(TBSV) is a model virus that can replicate a small replicon RNA in
Saccharomyces cerevisiae
and in plants. The tombusvirus replicase complex contains heat shock protein 70 (Hsp70), an abundant cytosolic chaperone, which is required for TBSV replication. To dissect the function of Hsp70 in TBSV replication, in this paper we use an Hsp70 mutant (
ssa1 ssa2
) yeast strain that supports a low level of TBSV replication. Using confocal laser microscopy and cellular fractionation experiments, we find that the localization of the viral replication proteins changes to the cytosol in the mutant cells from the peroxisomal membranes in wild-type cells. An in vitro membrane insertion assay shows that Hsp70 promotes the integration of the viral replication proteins into subcellular membranes. This step seems to be critical for the assembly of the viral replicase complex. Using a gene-silencing approach and quercetin as a chemical inhibitor to downregulate Hsp70 levels, we also confirm the significance of cytosolic Hsp70 in the replication of TBSV and other plant viruses in a plant host. Taken together, our results suggest that cytosolic Hsp70 plays multiple roles in TBSV replication, such as affecting the subcellular localization and membrane insertion of the viral replication proteins as well as the assembly of the viral replicase.
Induction of APOBEC3 In Vivo Causes Increased Restriction of Retrovirus Infection
Authors: Okeoma Chioma M. , Low Audrey , Bailis Will , Fan Hung Y. , Peterlin B. Matija , Ross Susan R.
Published: January 2009

APOBEC3 proteins are important cellular factors that restrict infection by a number of viruses, including human immunodeficiency virus type 1 (HIV-1). Previously, we found that the mouse APOBEC3 (mA3) restricts infection by mouse mammary tumor virus (MMTV) in its natural host. Dendritic cells (DCs) are the first in vivo targets of MMTV infection. In this study, we demonstrate that mA3 expressed in target cells restricts MMTV infection in DCs ex vivo and in vivo. By comparing infection of DCs from mA3+/+and mA3−/−mice with one-hit viruses, we show that mA3 expression in target cells blocked MMTV infection at a postentry step and acted together with virion-packaged mA3 to inhibit infection. Similar results were obtained upon infection of mouse DCs with HIV-1 cores pseudotyped with vesicular stomatitis virus G protein. In addition, treatment of cells or mice with lipopolysaccharide (LPS) caused increased levels of mA3 expression and rendered them resistant to MMTV infection. Alpha interferon treatment had a similar effect. This LPS-induced resistance to infection was seen only in mA3+/+mice and not in mA3−/−mice, arguing that mA3 is the major anti-MMTV restriction factor that is induced upon DC maturation. Thus, increasing the levels of this intrinsic antiretroviral factor in vivo can lead to increased levels of restriction because of higher levels of both cell-intrinsic as well as virion-packaged APOBEC3.
HLA-Associated Viral Mutations Are Common in Human Immunodeficiency Virus Type 1 Elite Controllers
Authors: Miura Toshiyuki , Brumme Chanson J. , Brockman Mark A. , Brumme Zabrina L. , Pereyra Florencia , Block Brian L. , Trocha Alicja , John Mina , Mallal Simon , Harrigan P. Richard , Walker Bruce D.
Published: January 2009

Elite controllers (EC) of human immunodeficiency virus type 1 (HIV-1) maintain viremia below the limit of detection without antiretroviral treatment. Virus-specific cytotoxic CD8
+
T lymphocytes are believed to play a crucial role in viral containment, but the degree of immune imprinting and compensatory mutations in EC is unclear. We obtained plasma
gag
,
pol
, and
nef
sequences from HLA-diverse subjects and found that 30 to 40% of the predefined HLA-associated polymorphic sites show evidence of immune selection pressure in EC, compared to approximately 50% of the sites in chronic progressors. These data indicate ongoing viral replication and escape from cytotoxic T lymphocytes are present even in strictly controlled HIV-1 infection.
Expression of Murine APOBEC3 Alleles in Different Mouse Strains and Their Effect on Mouse Mammary Tumor Virus Infection
Authors: Okeoma Chioma M. , Petersen Josiah , Ross Susan R.
Published: January 2009

Recent work has shown that mouse APOBEC3 restricts infection by mouse mammary tumor virus (MMTV) and murine leukemia virus (MLV) and that there are polymorphic APOBEC3 alleles found in different inbred mouse strains. For example, C57BL/6 mice, which are resistant to Friend MLV (F-MLV), encode a APOBEC3 gene different from that encoded by F-MLV-susceptible BALB/c mice; the predominant RNA produced in C57BL/6 mice lacks exon 5 (mA3
−5
) and encodes a protein with 15 polymorphic amino acids. It has also been reported that BALB/c mice produce only a variant RNA that lacks exon 2 (mA3
−2
). In this study, we examined the effect of these polymorphic APOBEC3 proteins on MMTV infection. We found that the major RNA made in C57BL/6 and B10.BR mice lacks exon 5 but that BALB/c and C3H/HeN mice predominantly express an RNA that contains all nine exons. In addition to producing the splice variant, C57BL/6 and B10.BR cells and tissues had levels of mA3 RNA fivefold higher than those from BALB/c and C3H/HeN mice. A cloned C57BL/6-derived mA3 protein lacking exon 5 inhibited MMTV infection better than a cloned full-length protein derived from 129/Ola RNA when packaged into MMTV virions. We also tested dendritic cells derived from different inbred mouse strains for their abilities to be infected by MMTV and showed that susceptibility to infection correlated with the presence of the exon 5-encoding allele. In vivo susceptibility to infection cosegregated with the inherited mA3 allele in a C57BL/6 × BALB/c backcross analysis. Moreover, virus produced in vivo in the mammary tissue of mA3 knockout and BALB/c mice was more infectious than that produced in the tissue of C57BL/6 mice. These data indicate that mA3 plays a role in the genetics of susceptibility and resistance to MMTV infection.
A case-control study on occupational risk factors for sino-nasal cancer
Authors: d’Errico A , Pasian S , Baratti A , Zanelli R , Alfonzo S , Gilardi L , Beatrice F , Bena A , Costa G
Published: January 2009

Objectives:

Sino-nasal cancer has been consistently associated with exposure to wood dust, leather dust, nickel and chromium compounds; for other occupational hazards, the findings are somewhat mixed. The aim of this study was to investigate the risk of sino-nasal epithelial cancer (SNEC) by histological type with prior exposure to suspected occupational risk factors and, in particular, those in metalworking.

Methods:

Between 1996 and 2000, incident cases were collected on a monthly basis from hospitals throughout the Piedmont region of Italy by the regional Sino-nasal Cancer Registry. A questionnaire on occupational history, completed by 113 cases and 336 hospital controls, was used to assign exposure to occupational hazards. The relationship between SNEC and cumulative exposure to these hazards was explored using unconditional logistic regression to statistically adjust for age, sex, smoking and co-exposures, allowing for a 10-year latency period.

Results:

The risk of adenocarcinoma was significantly increased with ever-exposure to wood dust (odds ratio; OR = 58.6), and to leather dust (OR = 32.8) and organic solvents (OR = 4.3) after controlling for wood dust, whereas ever-exposure to welding fumes (OR = 3.7) and arsenic (OR = 4.4) significantly increased the risk for squamous cell carcinoma. For each of these hazards, a significant increasing trend in risk across ordered cumulative exposure categories was found and, except for arsenic, a significantly increased risk with ever-exposure at low intensity. Treating cumulative exposure on a continuous scale, a significant effect of textile dusts was also observed for adenocarcinoma. For a mixed group of other histological types, a significant association was found with wood dust and organic solvents.

Conclusions:

Some occupational risk factors for SNEC were confirmed, and dose–response relationships were observed for other hazards that merit further investigation. The high risk for adenocarcinoma with low-intensity exposure to wood dust lends support for a reduction in the occupational threshold value.
Paleomagnetism and magnetic mineralogy of the Nahant gabbro and tonalite, eastern Massachusetts
Authors: Weisse Patricia A. , Haggerty Stephen E. , Brown Laurie L.
Published: January 2009

Paleomagnetic analyses of the Nahant gabbro and an associated tonalite of eastern Massachusetts reveal five separate populations of paleomagnetic directions. The gabbro and tonalite, exposed in the northernmost portion of the Boston Basin, were selected for this study because of the lack of significant macroscopic evidence of penetrative metamorphism or deformation. The tonalite has not been radiometrically dated; however, an Ordovician date has been reported for the gabbro. Detailed petrographic data indicate that the five populations of paleomagnetic directions obtained for the gabbro and tonalite correspond to five styles of magnetic mineral alteration.A mean alteration index was calculated for each site in the Nahant gabbro and tonalite. There is an apparent relationship between magnetite alteration and normalized intensity at a given demagnetization level, with normalized intensity decreasing as magnetite alteration increases. This relationship illustrates the interdependence between paleomagnetic properties and magnetic minerals. Alteration of these minerals is probably associated with periods of magnetic overprinting.Autometasomatism is believed to have occurred in the gabbro. Fluid flushing initiated plagioclase decomposition, liberating Ca + Al + Si to form Al-rich (4–10 wt.% Al2O3) titanite (sphene, CaTiSiO5). Whether the metasomatism was deuteric or the result of postdeuteric hydrothermal activity has not been determined.The Nahant gabbro poles are interpreted as representing either a deuteric or a metasomatic chemical remanent magnetization (CRM). The tonalite pole is interpreted as a deuteric CRM. The gabbro and tonalite poles are similar to a number of poles from Ordovician to Devonian intrusives in the Acadia terrane, including the St. Stephen and St. George plutons.Petrographic examination of polished sections from the Devonian St. Stephen and St. George plutons reveals evidence for alteration of primary magnetic mineral assemblages. Similarities exist between these alterations and alterations observed in the Nahant suite, most notably, the formation of titanite from Fe–Ti oxides. The repeated determination of similar poles on intrusive rocks in the Acadia terrane suggests there may be some tectonic or geomagnetic significance to poles from intrusives; however, without more data pertaining to the timing of metasomatic events observed in the Nahant suite and the St. Stephen and St. George plutons, the age and significance of these poles cannot be interpreted with certainty.
U–Pb zircon and sphene geochronology of a composite Archean granitoid batholith, Favourable Lake area, northwestern Ontario
Authors: Corfu F. , Krogh T. E. , Ayres L. D.
Published: January 2009

U–Pb zircon and sphene data for several phases of composite batholiths in the Favourable Lake area of the Superior Province indicate two major periods of plutonism separated by a hiatus of over 200 Ma.A trondhjemite, which now forms a metamorphosed remnant within a batholith, was emplaced 2950 ± 5 Ma ago during an early plutonic event. The second and dominant plutonic period occurred between [Formula: see text] and 2711.0 ± 2.0 Ma ago; these are the ages of the earliest and the latest widespread phase of the batholiths, respectively. Ages of 2716.3 ± 1.4 and 2716 ± 4 Ma for zircons of two minor dioritic phases also fall within this interval. Metamorphic zircons about 2730 and 2715 Ma old from another unit of the batholith indicate a temporal correlation between metamorphism and main plutonic pulses.Sphenes from two samples near the margins of the batholiths yield the same age of 2711 ± 2 Ma as coexisting zircons and date the primary crystallization of the rocks. In contrast, sphenes from six samples from the interior of a batholith yield ages of 2680 ± 10 Ma, which are significantly younger than primary ages of 2950–2716 Ma of coexisting zircons. These sphene ages probably record cooling below about 500 °C during a long and complex cooling process.Several of the studied zircon populations exhibit complex discordance patterns reflecting multiple stages of Pb loss. Zircons in rocks predating the 2700–2730 Ma old metamorphic–plutonic event experienced Pb loss during this event, probably by annealing. A second low-grade event apparently caused chemical alteration of high-U zircon domains and Pb loss about 1750 Ma ago. A late stage of Pb loss affected near-surface zircon domains about 600–0 Ma ago.
Pingo ice of the western Arctic coast, Canada
Authors: Mackay J. Ross
Published: January 2009

A field study of pingo ice exposures shows that all pingos contain pore ice and varying proportions of intrusive ice, segregated ice, dilation crack ice, and ice wedge ice. The intrusive ice is derived from water in a subpingo water lens. The ice is usually pure and columnar grained with c axes normal to the direction of heat flow. The columnar grains tend to develop parallel lines normal to the c axis upon exposure to radiation. Precise surveys of pingo growth for the 1973–1983 period show that displacement vectors are upward and radially outward and that radial dilation cracks are produced by circumferential stretching. The dilation cracks, which can open at any time of the year, become infilled with surface water and also with soil from the pingo overburden. The cumulative width of the dilation crack ice approximates the stretch of the pingo overburden as it is domed by pingo growth. Dilation crack ice is vertically banded. The bands are much wider than those in ice wedge ice and have less vertical taper to them. Segregated ice, under high subpermafrost pore-water pressures, may grow in medium-grained sands. Calculations based upon the 1973–1983 growth of one pingo with an intrusive ice core show that the annual increment of intrusive ice is greatly exceeded by pore ice and segregation ice, an observation probably true for many pingos.
Strata-bound tourmaline in the Archaean Malene supracrustals, West Greenland
Authors: Appel Peter W. Uitterdijk
Published: January 2009

Thin tourmaline-rich layers closely associated with strata-bound tungsten mineralization occur in layered amphibolites and metasediments of the Archaean Malene supracrustals in West Greenland. Locally, tourmaline is intergrown with scheelite. Microprobe analyses showed that the tourmaline is of intermediate composition, between schorl and dravite, with small variations in composition in different layers. The tourmaline is interpreted as being of submarine exhalative origin.
Magnetotelluric measurements in La Malbaie area (Quebec): the anomalous vertical magnetic field
Authors: Chouteau Michel
Published: January 2009

Magnetotelluric soundings were recorded in 1980–1981 at Ste-Mathilde near La Malbaie, Quebec for periods of 0.04–200 s. The present study deals only with single-station vertical transfer functions. Those functions show very characteristic features in their responses versus period. Of particular interest is a large in-phase (P) peak corresponding to a quadrature (Q) minimum between 0.1 and 0.2 s. For those periods, induction arrows indicate no obvious correlation between the anomalous vertical magnetic field (Z) and the conductive zone of Ste-Mathilde. Rather, they point toward the Malbaie River to the southwest of the survey zone. A possible model for the source of the vertical magnetic field is a shallow N130°E vertical dyke-type conductor, the top of which is some 1400 m under the Malbaie River valley. An interpretation could well be that it is one of the major graben faults related to the meteoritic impact crater of Charlevoix.
Palynology and age of the Scott Inlet inliers of Baffin Island (Northwest Territories)
Authors: Burden Elliott , Holloway David
Published: January 2009

Scott Inlet inliers, previously regarded as Cretaceous–Paleogene, are reinterpreted on the basis of palynomorphs as Quaternary deposits derived from the erosion and transport of nearby (probably offshore) Cretaceous strata during periods of high sea level.
Hydrodynamic distribution of palynomorphs in a fluvial succession, Yukon
Authors: Catto N. R.
Published: January 2009

Investigation of a sequence of alternating sand and silt deposits formed in an ephemeral braided stream channel adjacent to the modem Caribou River, Yukon, revealed differences in the palynological spectra of the sediment types. Picea, Betula, Alnus, and Gramineae are more concentrated in the silt units, whereas Cyperaceae, Chenopodium, Lycopodium, and Ericaceae are preferentially concentrated in the sand strata. These distribution patterns reflect the hydrodynamic properties of the grains, in addition to environmental differences. Grains of Picea, Betula, and Alnus settle through still water at the same rates as silt-sized quartz particles and are therefore concentrated in the portion of the deposit derived from the stream's suspended load. Thus, increases in percentages of these palynomorphs with decreasing grain size may not reflect vegetation changes or climatic alterations but may be consequences of the hydrodynamic situation.
EFFECT OF ALIGNMENT ON THE TEMPERATURE–RESISTANCE RESPONSE OF DIELECTROPHORETICALLY ASSEMBLED MULTIWALLED CARBON NANOTUBE FILMS
Authors: WIJAYA I. PUTU MAHENDRA , RODRIGUEZ ISABEL , MHAISALKAR S. G.
Published: January 2009

The assembly of multiwalled carbon nanotube (MWCNT) films through dielectrophoresis is described and the electrical response of aligned and randomly oriented MWCNT films to temperature variations is evaluated. The resistance of the randomly oriented MWCNT films was found to decrease exponentially with temperature. The decrease was less marked when the films were annealed and kept dehydrated during the electrical measurements. Alignment of MWCNTs led to an apparent reduction in the electrical response of the films with temperature changes and a small measurement-to-measurement variability, suggesting that dielectrophoresis-aligned MWCNT films would be more reproducible detectors in applications exploiting CNT-mediated electronic sensing.
THE ANOMALOUS ELECTRODYNAMIC CHARACTERISTICS AND POLARIZED-ORIENTED MULTILAYER MOLECULAR STRUCTURE OF MRET-ACTIVATED WATER
Authors: SMIRNOV IGOR
Published: January 2009

The anomalous electrodynamic characteristics (dielectric permittivity and electrical conductivity) of MRET water subjected to applied EMF (electromagnetic field) in the area of a very low range of frequencies were discovered during experiments conducted at Moscow State University, Russia. This confirmed the high level of long range dynamic structuring of water molecules in polarized-oriented multilayer formations in activated water produced with the help of the MRET activation process. The similarity of molecular formations of cell water and MRET-activated water contributes to their compatibility, easy bioavailability and assimilation of MRET-activated water into biological systems. The introduction of MRET water into biological systems can contribute to the enhancement of the cellular transduction mechanism and the proper functioning of cells in biological systems. The significant positive effect of MRET-activated water regarding tumor resistance in animals was observed in experiments conducted on 500 mice at Kiev Institute of Experimental Pathology, Oncology and Radiobiology, Ukrainian Academy of Science.
TITANIUM-CARBIDE-INFUSED PHENOLIC BALSA FOAM NANOCOMPOSITE
Authors: RANGARI VIJAYA K. , HASSAN TARIG A. , MAYO CLIFTON , JEELANI SHAIK
Published: January 2009

A sonochemical technique is developed to infuse titanium carbide nanoparticles into phenolic balsa foam material. Commercially available phenolic balsa foam resin solution (part A) is mixed with titanium carbide ( TiC ~ 80 nm ) nanoparticles, and irradiated with a high intensity ultrasonic horn. In the next step, the modified phenolic balsa foam resin solution containing titanium carbide nanoparticles is mixed with part B (containing phenol sulfonic acid, a catalyst) through a high speed mechanical stirrer. The reaction mixture is then cast into a rectangular mold to fabricate nanophased foam panels. Test coupons are cut precisely from the panels to carry out thermal, morphological and mechanical characterizations. The as-prepared foams are characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The SEM studies show that the particles are well dispersed over the entire volume of the matrix, with minimal agglomeration. The foam cell structures are well-ordered and uniform in size and shape. The TGA analysis indicates that the nanophased foams are thermally more stable than the corresponding neat systems. Quasi-static compression tests have been carried out for both nanophased and neat foam systems. The test results show a significant increase in the compressive strength (108%) and modulus (135%) compared to the neat system. These improvements in compressive properties have been observed repeatedly for multiple batches and with a minimum of five specimens tested from each batch. Details of the synthesis procedure and thermal and mechanical characterizations are presented in this paper.
A HIGH PERFORMANCE LARGE SPARSE SYMMETRIC SOLVER FOR THE MESHFREE GALERKIN METHOD
Authors: WU S. C. , ZHANG H. O. , ZHENG C. , ZHANG J. H.
Published: January 2009

One main disadvantage of meshfree methods is that their memory requirement and computational cost are much higher than those of the usual finite element method (FEM). This paper presents an efficient and reliable solver for the large sparse symmetric positive definite (SPD) system resulting from the element-free Galerkin (EFG) approach. A compact mathematical model of heat transfer problems is first established using the EFG procedure. Based on the widely used Successive Over-Relaxation–Preconditioned Conjugate Gradient (SSOR–PCG) scheme, a novel solver named FastPCG is then proposed for solving the SPD linear system. To decrease the computational time in each iteration step, a new algorithm for realizing multiplication of the global stiffness matrix by a vector is presented for this solver. The global matrix and load vector are changed in accordance with a special rule and, in this way, a large account of calculation is avoided on the premise of not decreasing the solution's accuracy. In addition, a double data structure is designed to tackle frequent and unexpected operations of adding or removing nodes in problems of dynamic adaptive or moving high-gradient field analysis. An information matrix is also built to avoid drastic transformation of the coefficient matrix caused by the initial-boundary values. Numerical results show that the memory requirement of the FastPCG solver is only one-third of that of the well-developed AGGJE solver, and the computational cost is comparable with the traditional method with the increas of solution scale and order.
MODELING, ANALYSIS AND RELIABILITY OF SEISMICALLY EXCITED STRUCTURES: COMPUTATIONAL ISSUES
Authors: FRAGIADAKIS MICHALIS , PAPADRAKAKIS MANOLIS
Published: January 2009

A critical review of the current state of the art of the computing practices adopted by the earthquake engineering community is presented. Advanced computational tools are necessary for estimating the demand on seismically excited structures. Such computational methodologies can provide valuable information on a number of engineering parameters which have been proven essential for earthquake the engineering practice. The discussion extends from the finite element modeling of earthquake-resistant structures and the analysis procedures currently used to future developments considering the calculation of uncertainty and methodologies which rely on sophisticated computational methods. The objective is to provide a common ground of collaboration between the earthquake engineering and computational mechanics communities in an effort to mitigate future earthquake losses.
Making sense of sensors
Authors: Wright Alex
Published: January 2009

Researchers are recognizing the potential of position sensors to help them overcome the limitations of traditional user interfaces.
The first internet president
Authors: Greengard Samuel
Published: January 2009

Barak Obama's presidential campaign utilized the Internet and information technology unlike any previous political campaign. How politicians and the public interact will never be the same.
Economic and business dimensionsThe extent of globalization of software innovation
Authors: Arora Ashish , Drev Matej , Forman Chris
Published: January 2009

Will the software development laboratories follow the production mills?
Parallel programming with transactional memory
Authors: Drepper Ulrich
Published: January 2009

While still primarily a research project, transactional memory shows promise for making parallel programming easier.
Improving performance on the internet
Authors: Leighton Tom
Published: January 2009

Given the Internet's bottlenecks, how can we build fast, scalable, content-delivery systems?
Women in computing---take 2
Authors: Klawe Maria , Whitney Telle , Simard Caroline
Published: January 2009

Inspiring, recruiting, and retaining women for a career in computing remains a challenge.
Building secure web applications with automatic partitioning
Authors: Chong Stephen , Liu Jed , Myers Andrew C. , Qi Xin , Vikram K. , Zheng Lantian , Zheng Xin
Published: January 2009

Swift is a new, principled approach to building Web applications that are
secure by construction.
Modern Web applications typically implement some functionality as client-side JavaScript code, for improved interactivity. Moving code and data to the client can create security vulnerabilities, but currently there are no good methods for deciding when it is secure to do so.

Swift automatically partitions application code while providing assurance that the resulting placement is secure and efficient. Application code is written as Java-like code annotated with information flow policies that specify the confidentiality and integrity of Web application information. The compiler uses these policies to automatically partition the program into JavaScript code running in the client browser and Java code running on the server. To improve interactive performance, code and data are placed on the client. However, security-critical code and data are always placed on the server. The compiler may also automatically replicate code across the client and server, to obtain both security and performance.