bluuebunny/crossref_metadata_2025 huggingface dataset:
Intracellular Ca2+ and TRPM5‐mediated membrane depolarization produce ATP secretion from taste receptor cells
Authors: Huang Yijen A. , Roper Stephen D.
Published: May 2010

ATP is a transmitter secreted from taste bud receptor (Type II) cells through ATP‐permeable gap junction hemichannels most probably composed of pannexin 1. The elevation of intracellular Ca2+ and membrane depolarization are both believed to be involved in transmitter secretion from receptor cells, but their specific roles have not been fully elucidated. In the present study, we show that taste‐evoked ATP secretion from mouse vallate receptor cells is evoked by the combination of intracellular Ca2+ release and membrane depolarization. Unexpectedly, ATP secretion is not blocked by tetrodotoxin, indicating that transmitter release from these cells still takes place in the absence of action potentials. Taste‐evoked ATP secretion is absent in receptor cells isolated from TRPM5 knockout mice or in taste cells from wild type mice where current through TRPM5 channels has been eliminated. These findings suggest that membrane voltage initiated by TRPM5 channels is required for ATP secretion during taste reception. Nonetheless, even in the absence of TRPM5 channel activity, ATP release could be triggered by depolarizing cells with KCl. Collectively, the findings indicate that taste‐evoked elevation of intracellular Ca2+ has a dual role: (1) Ca2+ opens TRPM5 channels to depolarize receptor cells and (2) Ca2+ plus membrane depolarization opens ATP‐permeable gap junction hemichannels.
Mitigation of Fretting Fatigue Damage in Blade and Disk Pressure Faces With Low Plasticity Burnishing
Authors: Prevéy Paul S. , Jayaraman N. , Ravindranath Ravi A. , Shepard Michael
Published: May 2010

Low plasticity burnishing (LPB) is now established as a surface enhancement technology capable of introducing through-thickness compressive residual stresses in the edges of gas turbine engine blades and vanes to mitigate foreign object damage (FOD). The “fatigue design diagram” (FDD) method has been described and demonstrated to determine the depth and magnitude of compression required to achieve the optimum high cycle fatigue strength, and to mitigate a given depth of damage characterized by the fatigue stress concentration factor, kf. LPB surface treatment technology and the FDD method have been combined to successfully mitigate a wide variety of surface damage ranging from FOD to corrosion pits in titanium and steel gas turbine engine compressor and fan components. LPB mitigation of fretting-induced damage in Ti–6Al–4V in laboratory samples has now been extended to fan and compressor components. LPB tooling technology recently developed to allow the processing of the pressure faces of fan and compressor blade dovetails and mating disk slots is described. Fretting-induced microcracks that form at the pressure face edge of bedding on both the blade dovetail and the dovetail disk slots in Ti-6-4 compressor components can now be arrested by the introduction of deep stable compression in conventional computer numerical control (CNC) machine tools during manufacture or overhaul. The compressive residual stress field design method employing the FDD approach developed at Lambda Technologies is described in application to mitigate fretting damage. The depth and magnitude of compression and the fatigue and damage tolerance achieved are presented. It was found that microcracks as deep as 0.030in.(0.75mm) large enough to be readily detected by current nondestructive inspection (NDI) technology can be fully arrested by LPB. The depth of compression achieved could allow NDI screening followed by LPB processing of critical components to reliably restore fatigue performance and extend component life.
Frequency modulation atomic force microscope observation of TiO2(110) surfaces in water
Authors: Sasahara Akira , Tomitori Masahiko
Published: May 2010

Rutile titanium dioxide (TiO2) (110) surfaces were examined in water using a frequency modulation atomic force microscope. On the surfaces cleaned by Ar+ sputtering and annealing in ultrahigh vacuum, step-terrace structure was observed. The inlets at the steps and the pits on the terraces indicated erosion of the surface in water. Strings extended to the [001] direction were occasionally observed in the topography images and assigned to the clusters of the H2O molecules. The tip experienced a repulsive force when the vertical tip position of z was less than 6 nm from the surface, and the force oscillated at z at less than 2 nm. The repulsive force originated from the disruption of the hydrogen bonding network of H2O molecules formed on the hydrophilic sputter-annealed surface. The oscillatory force arose from structural alternate order-disorder transitions of the H2O molecules at the gap between the tip and the TiO2 surfaces. On the TiO2 surface annealed in air, no strings were observed in the topography images. The tip experienced an attractive force before experiencing a repulsive force in its approach to the surface. Oscillatory behavior was not observed in the force curve. The air-annealed TiO2 and tip surfaces were both hydrophobic and attracted to each other to expel the H2O molecules from their gap. Ordering the H2O molecules at the gap between the two hydrophobic surfaces was entropically unfavorable.
Molecular resolution investigation of tetragonal lysozyme (110) face in liquid by frequency-modulation atomic force microscopy
Authors: Nagashima Ken , Abe Masayuki , Morita Seizo , Oyabu Noriaki , Kobayashi Kei , Yamada Hirofumi , Ohta Masahiro , Kokawa Ryohei , Murai Ryota , Matsumura Hiroyoshi , Adachi Hiroaki , Takano Kazufumi , Murakami Satoshi , Inoue Tsuyoshi , Mori Yusuke
Published: May 2010

In order to determine the molecular structure by x-ray diffraction analysis, it is very important to grow high quality protein crystals. The molecular resolution imaging of soluble protein crystals such as the tetragonal lysozyme (110) face in saturated solution is demonstrated using frequency-modulation atomic force microscopy (FM-AFM). The surface structure of the (110) face and the crystallographic position of individual molecules were determined from molecular resolution images. For observation of protein crystals, FM-AFM is a favorable technique as an alternative to contact mode or amplitude-modulation AFM.
The Climate Change Debates
Authors: Kitcher Philip
Published: May 2010

Kitcher's essay review examines eight books that explore causes and consequences of the debates over climate change. (Plus:
online discussion
)
Negative Feedback in Noncanonical NF-κB Signaling Modulates NIK Stability Through IKKα-Mediated Phosphorylation
Authors: Razani Bahram , Zarnegar Brian , Ytterberg A. Jimmy , Shiba Travis , Dempsey Paul W. , Ware Carl F. , Loo Joseph A. , Cheng Genhong
Published: May 2010

Feedback inhibition of the central regulator of noncanonical NF-κB signaling is mediated by its target kinase.
Evolving Bacteria and Computers
Authors: Ray L. Bryan
Published: May 2010

A bacterial regulatory network is compared to a computer operating system.
Science Signaling
Podcast: 25 May 2010
Authors: Hsu Wei , VanHook Annalisa M.
Published: May 2010

The balance between WNT and FGF signaling influences the mode of bone formation in the skull.
Phase 2a Randomized Controlled Trial of Short-Term Activity, Safety, and Pharmacokinetics of a Novel Nonnucleoside Reverse Transcriptase Inhibitor, RDEA806, in HIV-1-Positive, Antiretroviral-Naïve Subjects
Authors: Moyle Graeme , Boffito Marta , Stoehr Albrecht , Rieger Armin , Shen Zancong , Manhard Kimberly , Sheedy Beth , Hingorani Vijay , Raney Anneke , Nguyen Mai , Nguyen Tranh , Ong Voon , Yeh Li-Tain , Quart Barry
Published: May 2010

RDEA806 is a novel nonnucleoside reverse transcriptase inhibitor (NNRTI) with potent
in vitro
activity against wild-type and NNRTI-resistant HIV-1. A phase 2a randomized, double-blind, placebo-controlled, dose-escalating study evaluated the short-term antiviral activity, safety, and pharmacokinetics (PKs) of RDEA806 monotherapy in antiretroviral-naïve, HIV-1-infected subjects. The subjects were randomized to four cohorts comprising four dosage regimens and two formulations of RDEA806 or placebo in a 3:1 ratio within each cohort. The investigators were blinded to the results for each cohort. The subjects received RDEA806 or placebo for 7 days. The primary end point was the change in the HIV RNA load from the baseline to day 9 for each of the four RDEA806 dose regimens compared to that achieved with placebo. The RDEA806 PKs and the immune response to RDEA806 were evaluated along with the safety and tolerability of each dose. Of a total of 48 enrolled subjects, 36 subjects (9 in each cohort) were randomized to RDEA806 study drug, and 12 (3 in each cohort) took placebo. A statistically significant decrease in the viral load from the baseline to day 9 was observed for all RDEA806 treatment groups (
P
< 0.001). On day 9, the mean changes in the HIV RNA load from that at the baseline were −1.95 log
10
copies/ml (400 mg twice a day), −1.39 log
10
copies/ml (600 mg once a day [q.d.]), −1.62 log
10
copies/ml (800 mg q.d.), and −1.70 log
10
copies/ml (1,000 mg q.d.). The pharmacokinetics were linear and dose proportional. Treatment with RDEA806 was well tolerated, and there were no discontinuations due to adverse events. In conclusion, all doses of RDEA806 were safe and well tolerated and exhibited robust antiretroviral activity in this short-term monotherapy study with antiretroviral-naïve HIV-infected subjects. RDEA806 is a potent and promising novel NNRTI.
Identification and Characterization of Small-Molecule Inhibitors of Yop Translocation in
Yersinia pseudotuberculosis
Authors: Harmon Dana E. , Davis Alison J. , Castillo Cynthia , Mecsas Joan
Published: May 2010

Type three secretion systems (TTSSs) are virulence factors found in many pathogenic Gram-negative species, including the family of pathogenic
Yersinia
spp.
Y
ersinia
pseudotuberculosis
requires the translocation of a group of effector molecules, called Yops, to subvert the innate immune response and establish infection. Polarized transfer of Yops from bacteria to immune cells depends on several factors, including the presence of a functional TTSS, the successful attachment of
Yersinia
to the target cell, and translocon insertion into the target cell membrane. Here we employed a high-throughput screen to identify small molecules that block translocation of Yops into mammalian cells. We identified 6 compounds that inhibited translocation of effectors without affecting synthesis of TTSS components and secreted effectors, assembly of the TTSS, or secretion of effectors. One compound, C20, reduced adherence of
Y.
pseudotuberculosis
to target cells. Additionally, the compounds caused leakage of Yops into the supernatant during infection and thus reduced polarized translocation. Furthermore, several molecules, namely, C20, C22, C24, C34, and C38, also inhibited ExoS-mediated cell rounding, suggesting that the compounds target factors that are conserved between
P
seudomonas
aeruginosa
and
Y.
pseudotuberculosis
. In summary, we have identified 6 compounds that specifically inhibit translocation of Yops into mammalian cells but not Yop synthesis or secretion.
Identification of the Novel
dfrK
-Carrying Transposon Tn
559
in a Porcine Methicillin-Susceptible
Staphylococcus aureus
ST398 Strain
Authors: Kadlec Kristina , Schwarz Stefan
Published: May 2010

The trimethoprim resistance gene
dfrK
was found to be part of the novel Tn
554
-related transposon Tn
559
integrated in the chromosomal
radC
gene of a porcine methicillin-susceptible
Staphylococcus aureus
ST398 strain. While Tn
559
and Tn
554
had similar arrangements of the transposase genes
tnpA
,
tnpB
, and
tnpC
, the Tn
554
-associated resistance genes
erm
(A) and
spc
were replaced by
dfrK
in Tn
559
. Circular forms of Tn
559
were detected and suggest the functional activity of this transposon.
Risk Factors for Fluconazole-Resistant Candidemia
Authors: Garnacho-Montero José , Díaz-Martín Ana , García-Cabrera Emilio , Ruiz Pérez de Pipaón Maite , Hernández-Caballero Clara , Aznar-Martín Javier , Cisneros José M. , Ortiz-Leyba Carlos
Published: May 2010

Previous studies have sought to determine the risk factors associated with candidemia caused by non-
albicans Candida
spp. or with potentially fluconazole-resistant
Candida
spp. (
C. glabrata
and
C. krusei
). Non-
albicans Candida
strains are a heterogeneous group that includes species with different levels of virulence, and only a limited number of
C. glabrata
isolates are resistant to fluconazole. We set out to identify the risk factors associated with microbiologically proven fluconazole-resistant candidemia. A prospective study including adult patients with candidemia was performed. Data were collected on patient demographics; underlying diseases; exposure to corticosteroids, antibiotics, or fluconazole; and invasive procedures. Risk factors associated either with non-
albicans Candida
spp. or potentially fluconazole-resistant
Candida
spp. (
C. glabrata
or
C. krusei
) or with
Candida
spp. with microbiologically confirmed fluconazole resistance were assessed using logistic regressions. We included 226 candidemia episodes. Non-
albicans Candida
isolates accounted for 53.1% of the fungal isolates, but only 18.2% of the cases were caused by potentially fluconazole-resistant organisms. Thirty isolates exhibited microbiologically confirmed fluconazole resistance. The multivariate analysis revealed that independent predictors associated with fluconazole-resistant
Candida
spp. were neutropenia (odds ratio [OR] = 4.94; 95% confidence interval [CI] = 1.50 to 16.20;
P
= 0.008), chronic renal disease (OR = 4.82; 95% CI = 1.47 to 15.88;
P
= 0.01), and previous fluconazole exposure (OR = 5.09; 95% CI = 1.66 to 15.6;
P
= 0.004). Independently significant variables associated with non-
albicans Candida
bloodstream infection or with potentially fluconazole-resistant
Candida
spp. did not include previous fluconazole exposure. We concluded that prior fluconazole treatment is an independent risk factor only for candidemia caused by microbiologically confirmed fluconazole resistant species. Our findings may be of value for selecting empirical antifungal therapy.
Mutational Analysis of VIM-2 Reveals an Essential Determinant for Metallo-β-Lactamase Stability and Folding
Authors: Borgianni Luisa , Vandenameele Julie , Matagne André , Bini Luca , Bonomo Robert A. , Frère Jean-Marie , Rossolini Gian Maria , Docquier Jean-Denis
Published: May 2010

Metallo-β-lactamase (MBL)-producing bacteria are emerging worldwide and represent a formidable threat to the efficacy of relevant β-lactams, including carbapenems, expanded-spectrum cephalosporins, and β-lactamase inactivator/β-lactam combinations. VIM-2 is currently the most widespread MBL and represents a primary target for MBL inhibitor research, the clinical need for which is expected to further increase in the future. Using a saturation mutagenesis approach, we probed the importance of four residues (Phe-61, Ala-64, Tyr-67, and Trp-87) located close to the VIM-2 active site and putatively relevant to the enzyme activity based on structural knowledge of the enzyme and on structure-activity relationships of the subclass B1 MBLs. The ampicillin MIC values shown by the various mutants were affected very differently depending on the randomized amino acid position. Position 64 appeared to be rather tolerant to substitution, and kinetic studies showed that the A64W mutation did not significantly affect substrate hydrolysis or binding, representing an important difference from IMP-type enzymes. Phe-61 and Tyr-67 could be replaced with several amino acids without the ampicillin MIC being significantly affected, but in contrast, Trp-87 was found to be critical for ampicillin resistance. Further kinetic and biochemical analyses of W87A and W87F variants showed that this residue is apparently important for the structure and proper folding of the enzyme but, surprisingly, not for its catalytic activity. These data support the critical role of residue 87 in the stability and folding of VIM-2 and might have strong implications for MBL inhibitor design, as this residue would represent an ideal target for interaction with small molecules.
Importance of Serum Concentration of Adefovir for Lamivudine-Adefovir Combination Therapy in Patients with Lamivudine-Resistant Chronic Hepatitis B
Authors: Mitsui Fukiko , Tsuge Masataka , Kimura Takashi , Kitamura Shosuke , Abe Hiromi , Saneto Hiromi , Kawaoka Tomokazu , Miki Daiki , Hatakeyama Tsuyoshi , Hiraga Nobuhiko , Imamura Michio , Kawakami Yoshiiku , Aikata Hiroshi , Takahashi Shoichi , Hayes C. Nelson , Igarashi Harue , Morimoto Kentaro , Shimizu Masao , Chayama Kazuaki
Published: May 2010

Lamivudine (LMV)-adefovir pivoxil (ADV) combination therapy suppresses the replication of LMV-resistant hepatitis B virus (HBV), although its efficacy in suppressing HBV varies among patients. This study analyzed the clinical, virological, and pharmaceutical factors that influence the effect of the combination therapy. Patients negative for hepatitis B virus e antigen (HBeAg) and with low HBV DNA titers immediately prior to the combination therapy effectively cleared serum HBV DNA (
P =
0.0348 and
P =
0.0310, respectively). The maximum concentration of ADV in serum (ADV
C
max
) was higher in patients who showed HBV DNA clearance (
P =
0.0392), and the cumulative clearance rates of HBV DNA were significantly higher in patients with ADV
C
max
equal to or greater than 24 ng/ml (
P =
0.0284). HBeAg negativity and lower HBV DNA at the start of the combination therapy and higher ADV
C
max
were found to be independent factors for serum HBV DNA clearance. Serum creatinine increased significantly during the combination therapy, and the ADV
C
max
was higher in patients with low creatinine clearance rates. In conclusion, higher serum concentrations of ADV are associated with a good response to therapy based on clearance of HBV DNA in serum. However, care should be taken to prevent worsening of renal function due to high ADV serum concentrations.
In Vitro
Activity of Azithromycin against Nontyphoidal
Salmonella enterica
Authors: Gunell Marianne , Kotilainen Pirkko , Jalava Jari , Huovinen Pentti , Siitonen Anja , Hakanen Antti J.
Published: May 2010

The
in vitro
activity of azithromycin against 1,237 nontyphoidal
Salmonella enterica
isolates collected from Finnish patients between 2003 and 2008 was investigated. Only 24 (1.9%) of the isolates tested and 15 (5.1%) of the 294 isolates with reduced fluoroquinolone susceptibility had azithromycin MICs of ≥32 μg/ml. These data show that azithromycin has good
in vitro
activity against nontyphoidal
S. enterica
, and thus, it may be a good candidate for clinical treatment studies of salmonellosis.
The BpeAB-OprB Efflux Pump of
Burkholderia pseudomallei
1026b Does Not Play a Role in Quorum Sensing, Virulence Factor Production, or Extrusion of Aminoglycosides but Is a Broad-Spectrum Drug Efflux System
Authors: Mima Takehiko , Schweizer Herbert P.
Published: May 2010

Most
Burkholderia pseudomallei
strains are intrinsically aminoglycoside resistant, mainly due to AmrAB-OprA-mediated efflux. Rare naturally occurring or genetically engineered mutants lacking this pump are aminoglycoside susceptible despite the fact that they also encode and express BpeAB-OprB, which was reported to mediate efflux of aminoglycosides in the Singapore strain KHW. To reassess the role of BpeAB-OprB in
B. pseudomallei
aminoglycoside resistance, we used mutants overexpressing or lacking this pump in either AmrAB-OprA-proficient or -deficient strain 1026b backgrounds. Our data show that BpeAB-OprB does not mediate efflux of aminoglycosides but is a multidrug efflux system which extrudes macrolides, fluoroquinolones, tetracyclines, acriflavine, and, to a lesser extent, chloramphenicol. Phylogenetically, BpeAB-OprB is closely related to
Pseudomonas aeruginosa
MexAB-OprM, which has a similar substrate spectrum. AmrAB-OprA is most closely related to MexXY, the only
P. aeruginosa
efflux pump known to extrude aminoglycosides. Since BpeAB-OprB in strain KHW was also implicated in playing a major role in export of acylated homoserine lactone (AHL) quorum-sensing molecules and in expression of diverse virulence factors, we explored whether this was also true in the strain 1026b background. The results showed that BpeAB-OprB was not required for AHL export, and mutants lacking this efflux system exhibited normal swimming motility and siderophore production, which were severely impaired in KHW
bpeAB-oprB
mutants. Biofilm formation was impaired in 1026b Δ(
amrRAB-oprA
) and Δ(
amrRAB-oprA
) Δ(
bpeAB-oprB
) mutants. At present, we do not know why our BpeAB-OprB susceptibility and virulence factor expression results with 1026b and its derivatives are different from those previously published for Singapore strain KHW.
Biosafety Level 2 Model of Pneumonic Plague and Protection Studies with F1 and Psa
Authors: Galván Estela M. , Nair Manoj Kumar Mohan , Chen Huaiqing , Del Piero Fabio , Schifferli Dieter M.
Published: May 2010

Attenuated
Yersinia pestis pgm
strains, such as KIM5, lack the siderophore yersiniabactin. Strain KIM5 does not induce significant pneumonia when delivered intranasally. In this study, mice were found to develop pneumonia after intranasal challenge with strain KIM5 when they were injected intraperitoneally with iron dextran, though not with iron sulfate. KIM5-infected mice treated daily with 4 mg iron dextran died in 3 days with severe pneumonia. Pneumonia was less severe if 4 mg iron dextran was administered only once before infection. The best-studied experimental vaccine against plague currently consists of the
Yersinia pestis
capsular antigen F1 and the type 3 secreted protein LcrV. The F1 antigen was shown to be protective against KIM5 infections in mice administered iron dextran doses leading to light or severe pneumonia, supporting the use of an iron dextran-treated model of pneumonic plague. Since F1 has been reported to be incompletely protective in some primates, and bacterial isolates lacking F1 are still virulent, there has been considerable interest in identifying additional protective subunit immunogens. Here we showed that the highly conserved Psa fimbriae of
Y. pestis
(also called pH 6 antigen) are expressed in murine organs after infection through the respiratory tract. Studies with iron dextran-treated mice showed that vaccination with the Psa fimbrial protein together with an adjuvant afforded incomplete but significant protection in the mouse model described. Therefore, further investigations to fully characterize the protective properties of the Psa fimbriae are warranted.
Parental smoking and pretend smoking in young children
Authors: de Leeuw Rebecca N H , Engels Rutger C M E , Scholte Ron H J
Published: May 2010

Objective

To investigate whether parental smoking was associated with smoking-related play behaviour in young children.

Design

Children were asked to pretend that they were grown-ups having dinner. They were invited to act out this situation in a play corner with a toy kitchen and a child-sized dining area, including a package of fake cigarettes on the table.

Setting

Children were tested individually at their school during regular school hours.

Participants

The sample consisted of 100 children between 4 and 8 years of age (mean=5.28, SD=0.94) of which 57% were boys. The majority of the children were born in The Netherlands (99%).

Measurements

The main outcome measure was whether or not a child pretended to be smoking a cigarette. Child and parent reports were used to assess parental smoking.

Findings

Findings revealed that 37% of the children had at least one ‘puff’ during their play. Children were more likely to pretend to smoke if they reported having smoking parents (OR=3.16, p=0.02; 95% CI=1.22 to 8.18). Analyses for the model with parent reports on parental smoking did not yield any direct association. Children's explicit attitudes were unrelated to their smoking-related play behaviour.

Conclusions

These findings indicate that young children, who reported having parents who smoke, already associate having dinner with a (after-dinner) cigarette.
Bar and restaurant workers' attitudes towards Norway's comprehensive smoking ban: a growth curve analysis
Authors: Braverman Marc T , Aarø Leif Edvard , Bontempo Daniel E , Hetland Jørn
Published: May 2010

Background

Norway passed legislation banning smoking in restaurants, bars and other public spaces in 2004. This study tracks changes in hospitality workers' attitudes towards Norway's ban over three time points, using growth modelling analysis to examine predictors of attitude change.

Methods

Participants were a national sample of 1525 bar and restaurant workers. Surveys were conducted, by phone or internet, one month before the ban's implementation and at 4 and 12 months thereafter. Exploratory principal components analysis of nine survey items revealed one primary attitude component. A latent growth model was fitted to the data to examine trajectories of attitude change and individual differences in rate of change.

Results

Respondents supported the ban before implementation and increased support at 4 months (p=0.021) and again at 12 months (p=0.001). Concern for one's job followed a quadratic trend, increasing at 4 months and decreasing at 12 months (p<0.001). All demographic categories were associated with attitude increase; rate of increase was greater for females than males. Two within-person variables—change in smoking status and change in job concern—strongly predicted (p<0.001) respondents' deviations from their predicted group trajectories, explaining over 70% of residual between-person slope variance.

Conclusions

Norway's hospitality workers increased their support of the ban over its first year. The strong influence of the within-person variables leads to two primary policy recommendations. First, support should be provided to assist cessation efforts and prevent relapse. Second, informational campaigns should inform hospitality workers about evidence that smoking bans are not economic threats to the industry.
Reduction of secondhand tobacco smoke in public places following national smoke-free legislation in Uruguay
Authors: Blanco-Marquizo Adriana , Goja Beatriz , Peruga Armando , Jones Miranda R , Yuan Jie , Samet Jonathan M , Breysse Patrick N , Navas-Acien Ana
Published: May 2010

Background

Smoke-free legislation eliminating tobacco smoke in all indoor public places and workplaces is the international standard to protect all people from exposure to secondhand smoke. Uruguay was the first country in the Americas and the first middle-income country in the world to enact a comprehensive smoke-free national legislation in March 2006.

Objective

To compare air nicotine concentrations measured in indoor public places and workplaces in Montevideo, Uruguay before (November 2002) and after (July 2007) the implementation of the national legislation.

Methods

Air nicotine concentrations were measured for 7–14 days using the same protocol in schools, a hospital, a local government building, an airport and restaurants and bars. A total of 100 and 103 nicotine samples were available in 2002 and 2007, respectively.

Results

Median (IQR) air nicotine concentrations in the study samples were 0.75 (0.2–1.54) μg/m3in 2002 compared to 0.07 (0.0–0.20) μg/m3in 2007. The overall nicotine reduction comparing locations sampled in 2007 to those sampled in 2002 was 91% (95% CI 85% to 94%) after adjustment for differences in room volume and ventilation. The greatest nicotine reduction was observed in schools (97% reduction), followed by the airport (94% reduction), the hospital (89% reduction), the local government building (86% reduction) and restaurants/bars (81% reduction).

Conclusion

Exposure to secondhand smoke has decreased greatly in indoor public places and workplaces in Montevideo, Uruguay, after the implementation of a comprehensive national smoke-free legislation. These findings suggest that it is possible to successfully implement smoke-free legislations in low and middle-income countries.
STUDIES OF THE DEVELOPMENT OF ZOSTERA MARINA L.: II. GERMINATION AND SEEDLING DEVELOPMENT
Authors: Taylor A. R. A.
Published: May 2010

Seeds of Zostera marina L. are shed in Prince Edward Island waters during mid to late summer and germinate the following spring. Occasionally seeds germinate in nature before winter; they can be germinated during autumn and winter in the laboratory. Elongation of cells of the cotyledon and doubled-back axial hypocotyl pushes the embryo out of the seed coat. Cell increase plays no part in this or subsequent elongation of cotyledon and hypocotyl. Leaves emerge through the slit-like opening at the top of the cotyledonary sheath. Hairs develop from cells of the convex surface of the basal swollen hypocotyl; two adventitious roots grow from the cotyledonary node, develop root hairs, and anchor the seedling. Stelar tissues of the hypocotyl and cotyledon differentiate at germination. No characteristically thickened tracheary elements differentiate in hypocotyl or cotyledon. In the hypocotyl, phloem differentiates around the central xylem parenchyma and abuts externally on endodermis which develops Casparian strips. Xylem parenchyma differentiates adaxially against the phloem in the single cotyledonary strand. Differentiation of procambium and vascular tissues in the leaf primordia follows as these expand. Vascularization of the stem nodes is complicated by differentiation of strands to the roots and leaves. All internodes except the first have one pair of cortical bundles. The pair of lateral veins of the first true leaf differentiate in connection with the stele at that node; the lateral bundles from each later-formed leaf pass through one internode as cortical bundles and unite with the stele in the node below.
TRANSLOCATION OF RADIOACTIVE SUGARS IN THE STEMS OF SOYBEAN SEEDLINGS
Authors: Nelson C. D. , Gorham Paul R.
Published: May 2010

Glucose-C14, fructose-C14, or sucrose-C14 were introduced into soybean seedlings through the cut petiole of one primary leaf. After 3 to 15 minutes the distribution of C14 throughout the plants was determined. Each of the three sugars was translocated as such without conversion to other compounds. Translocation was mainly downward from the point of introduction into the stem. Very little sugar was translocated to the primary leaf opposite the treated petiole or to the growing tip of the stem. Of the small amount of sugar that was translocated upward the bulk accumulated in the younger rather than the older trifoliate leaf.When glucose-C14 or fructose-C14 were used the radioactivity in the stem decreased logarithmically from the point of introduction. The downward translocation of both sugars was impeded at the nodes. Translocation was not inhibited by 10−2 M potassium cyanide. These hexoses were translocated both upward and downward past killed sections of stems. When sucrose-C14 was used the radioactivity in the stem decreased linearly from the point of introduction. Translocation of sucrose was not impeded at the nodes and was inhibited by 10−2 M potassium cyanide. Sucrose was not translocated either upward or downward past killed sections of stems.The minimum rate of translocation of both glucose and sucrose was the same. The rate was about 300 cm. per hour in the youngest seedlings and decreased with age to about 100 cm. per hour in the oldest seedlings.
STUDIES IN PLANT MINERAL NUTRITION: III. THE EFFECTS OF CALCIUM CONCENTRATION IN CULTURE SOLUTIONS UPON THE ABSORPTION OF IRON AND MANGANESE BY DWARF KIDNEY BEAN
Authors: Taper C. D. , Leach W.
Published: May 2010

Definite relationships between the absorption of iron, manganese, and calcium were revealed in experiments with dwarf kidney beans grown in complete nutrient solutions containing various concentrations of iron and manganese, and two concentrations of calcium. The effects of these treatments upon the leaf contents of iron and manganese were determined by spectrophotometric analysis.It was found that increase in the concentration of either one of the metals, iron or manganese, relative to the concentration of the other, in the culture solution, appeared to depress the concentration of the other in the leaves, regardless of calcium level in the solution. Further, increase in the calcium level appeared to depress the accumulation by the leaves of both iron and manganese, regardless of their concentrations in the culture solution and the ratio between them.The iron to manganese concentration ratio in the culture solution was a factor in determining the presence or absence of deficiency symptoms. With 42 p.p.m. of calcium in the culture solution, healthy plants resulted within an optimum iron: manganese ratio range of approximately 0.5 to 5.0, whereas, in the case of 143 p.p.m. of calcium, healthy plants resulted only when the ratio was 2, indicating a narrower optimum range for the higher calcium level. Iron: manganese ratios below the optimum range resulted in iron deficiency symptoms, and above this range, in manganese deficiency symptoms.The data suggest that a minimum content of each of the metals, iron and manganese, must be present in the leaf tissues in order that healthy plants may result.
ISOLATION AND FRACTIONATION OF LEAF PHOSPHATIDES
Authors: Kates Morris , Eberhardt Frank M.
Published: May 2010

Methods are described for the extraction of total lipids (including pigments) from leaves, under conditions minimizing the action of phosphatidase C on the phosphatides, and for the fractionation of the phosphatide components. The lipids were extracted with hot i-propanol, partitioned into chloroform, and freed from water-soluble substances by washing with water. Chromatography of the lipids on silicic acid – Celite columns yielded a pigment plus non-phosphatide fraction and the following four phosphatide fractions: Fraction I, consisting of inositol–carbohydrate phosphatides; Fraction II, containing mostly phosphatidyl ethanolamine, and some phosphatidyl serine; Fraction III, an unknown phosphatide; and Fraction IV, consisting predominately of phosphatidyl choline. Although the analytical data and the products of hydrolysis of the fractions indicate that complete resolution of the phosphatides has not been achieved, the methods described should be useful as a preliminary group fractionation, prior to further separation and purification steps. The presence of inositol phosphatides in leaves is reported here for the first time.
Geochronological constraints on the development of the Cross Lake greenstone belt, northwest Superior Province, Manitoba
Authors: Corkery M. T. , Davis D. W. , Lenton P. G.
Published: May 2010

Recent 1: 20 000 mapping combined with 11 age determinations from metavolcanic, metaplutonic, and metasedimentary rocks in the Cross Lake greenstone belt provide a framework for interpreting the stratigraphic, structural, intrusive, and metamorphic evolution of the belt. These data, in combination with U–Pb ages from adjacent granitoid domains, are used to model a cratonizing event in the northwest Superior Province.The Cross Lake greenstone belt is made up of three distinct unconformable groups of supracrustal rocks: (i) the Pipestone Lake Group (2760 Ma), a thick sequence of pillowed and massive tholeiitic basalt flows and related high level gabbros, inter-preted as a back-arc spreading sequence; (ii) the Gunpoint Group (2730 Ma), a fining-upward sequence of clastic sediments interbedded with rhyodacitic fragmental volcanic rocks; and (iii) the Cross Lake Group (<2710 Ma), a fining-upward, fluvial–marine clastic sedimentary sequence, with shoshonitic volcanic rocks near the top, deposited in a restricted basin. Angular unconformities occur between (i) the Pipestone Lake Group and the overlying Gunpoint and Cross Lake groups, and (ii) the Gunpoint Group and the younger Cross Lake Group.The greenstone belt is flanked by the plutonic Molson Lake Domain on the south and the largely metaplutonic Pikwitonei and granite–greenstone Gods Lake domains on the northwest. The northern contact is a major northeast-trending fault system with a dextral strike-slip component and vertical component indicative of relative uplift of the northwest side. The southern contact is a much broader zone of deformation in which a number of east-southeast-trending dextral fault zones imbricate Pipestone Lake and Gunpoint Group supracrustal rocks and, to a lesser extent, Molson Lake plutonic rocks.
CONSTRAINTS ON THE COSMOLOGICAL CONSTANT DUE TO SCALE INVARIANCE
Authors: ALURI PAVAN K. , JAIN PANKAJ , MITRA SUBHADIP , PANDA SUKANTA , SINGH NAVEEN K.
Published: May 2010

We consider the standard model with local scale invariance. The theory shows exact scale invariance of dimensionally regulated action. We show that massless gauge fields, which may be Abelian or non-Abelian, lead to vanishing contribution to the cosmological constant in this theory. This result follows in the quantum theory, to all orders in the gauge couplings. However, we have not considered contributions higher orders in the gravitational coupling. Similarly we also find that massless fermion fields yield null contribution to the cosmological constant. The effective cosmological constant in this theory is nonzero due to the phenomenon of cosmological symmetry breaking, which also gives masses to all the massive fields, besides generating the Planck mass. We find a simple relationship between the curvature scalar and the vacuum value of the Higgs field in the limit when we ignore all other contributions to the energy density besides the vacuum energy.
CONFORMAL INVARIANT INTERACTION OF A SCALAR FIELD WITH HIGHER SPIN FIELD IN AdSD
Authors: MANVELYAN RUBEN , MKRTCHYAN KARAPET
Published: May 2010

The explicit form of linearized gauge invariant interactions of scalar and general higher even spin fields in the AdSD space is obtained. In the case of general spin-ℓ a generalized "Weyl" transformation is proposed and the corresponding "Weyl" invariant action is constructed. In both cases the invariant actions of the interacting higher even spin gauge field and the scalar field include the whole tower of invariant actions for couplings of the same scalar with all gauge fields of smaller even spin. For the particular value of ℓ = 4, all results are in exact agreement with Ref. 1.
QUANTUM FIELD THEORIES OF STRONG INTERACTIONS
Authors: YAMAGUCHI YOSHIO
Published: May 2010

Strong interactions are described by the Quantum Field Theory due to Heisenberg–Pauli. We postulate that the one particle physical states with appropriate quantum numbers (fermions and bosons) must be expressed by the normalized Fock space state vectors, which can conveniently be (and approximately) calculated in their rest frame, using Tamm–Dancoff variational method. Interactions between two physical particles can be analyzed by the same Hamiltonian as for each physical particle state, similar to analyzing nucleus–nucleus collisions. Our theories are free from any ultraviolet divergency. Our one physical particle state is similar to bound state in quantum mechanics.
Effects of facial similarity on user responses to embodied agents
Authors: Vugt Henriette C. Van , Bailenson Jeremy N. , Hoorn Johan F. , Konijn Elly A.
Published: May 2010

We investigated the effects of facial similarity between users and embodied agents under different experimental conditions. Sixty-four undergraduates interacted with two different embodied agents: in one case the agent was designed to look somewhat similar to the user, and in the other case the agent was designed to look dissimilar. We varied between subjects how helpful the agent was for a given task. Results showed that the facial similarity manipulation sometimes affected participants' responses, even though they did not consciously detect the similarity. Specifically, when the agent was helpful, facial similarity increased participantsi ratings of involvement. However, when exposed to unhelpful agents, male participants had negative responses to the similar-looking agent compared to the dissimilar one. These results suggest that using facially similar embodied agents has a potential large downside if that embodied agent is perceived to be unhelpful.
Complex interaction
Authors: Janlert Lars-Erik , Stolterman Erik
Published: May 2010

An almost explosive growth of complexity puts pressure on people in their everyday doings. Digital artifacts and systems are at the core of this development. How should we handle complexity aspects when designing new interactive devices and systems? In this article we begin an analysis ofinteraction complexity. We portray different views of complexity; we explore not only negative aspects of complexity, but also positive, making a case for the existence ofbenigncomplexity. We argue that complex interaction is not necessarily bad, but designers need a deeper understanding of interaction complexity and need to treat it in a more intentional and thoughtful way. We examine interaction complexity as it relates to different loci of complexity:internal,external, andmediatedcomplexity. Our purpose with these analytical exercises is to pave the way for design that is informed by a more focused and precise understanding of interaction complexity.
Execution-time control for interrupt handling
Authors: Gregertsen Kristoffer Nyborg , Skavhaug Amund
Published: May 2010

This paper proposes that execution-time control features for interrupt handling should be added to the Ada standard library. By measuring the execution-time for interrupts separately the accuracy of task execution-time measurement will be also improved. It is described how the proposed features were implemented for the GNAT bare-board Ravenscar run-time environment on the Atmel AVR32 architecture. Test results for the implementation and an example of usage are presented.
Support for a real-time transactional model in distributed Ada
Authors: Tijero Héctor Pérez , Gutiérrez J. Javier , Harbour Michael González
Published: May 2010

This paper presents a proposal to integrate a generic technique to express complex scheduling and timing parameters of distributed transactions as a part of the Distributed Systems Annex of Ada (DSA). The technique allows real-time middleware implementations to change their scheduling policies for both the processing nodes and the networks with a minimal interference in the application code. The proposed mechanisms are managed by the middleware in a transparent way. The only requirement is an initial configuration operation, which can be generated automatically, and a single operation call to set an event identifier in each of the tasks that initiates a distributed transaction. The automatic process used to obtain the initial configuration of the distributed application, based on a real-time model, is also proposed. The implementation of this proposal is currently being developed.
Sedentary aging increases resting and exercise-induced intramuscular free radical formation
Authors: Bailey Damian M. , McEneny Jane , Mathieu-Costello Odile , Henry Robert R. , James Philip E. , McCord Joe M. , Pietri Sylvia , Young Ian S. , Richardson Russell S.
Published: May 2010

Mitochondrial free radical formation has been implicated as a potential mechanism underlying degenerative senescence, although human data are lacking. Therefore, the present study was designed to examine if resting and exercise-induced intramuscular free radical-mediated lipid peroxidation is indeed increased across the spectrum of sedentary aging. Biopsies were obtained from the vastus lateralis in six young (26 ± 6 yr) and six aged (71 ± 6 yr) sedentary males at rest and after maximal knee extensor exercise. Aged tissue exhibited greater ( P < 0.05 vs. the young group) electron paramagnetic resonance signal intensity of the mitochondrial ubisemiquinone radical both at rest (+138 ± 62%) and during exercise (+143 ± 40%), and this was further complemented by a greater increase in α-phenyl-tert-butylnitrone adducts identified as a combination of lipid-derived alkoxyl-alkyl radicals (+295 ± 96% and +298 ± 120%). Lipid hydroperoxides were also elevated at rest (0.190 ± 0.169 vs. 0.148 ± 0.071 nmol/mg total protein) and during exercise (0.567 ± 0.259 vs. 0.320 ± 0.263 nmol/mg total protein) despite a more marked depletion of ascorbate and uptake of α/β-carotene, retinol, and lycopene ( P < 0.05 vs. the young group). The impact of senescence was especially apparent when oxidative stress biomarkers were expressed relative to the age-related decline in mitochondrial volume density and absolute power output at maximal exercise. In conclusion, these findings confirm that intramuscular free radical-mediated lipid peroxidation is elevated at rest and during acute exercise in aged humans.
The effect of increased genioglossus activity and end-expiratory lung volume on pharyngeal collapse
Authors: Jordan Amy S. , White David P. , Owens Robert L. , Eckert Danny J. , Rahangdale Shilpa , Yim-Yeh Susie , Malhotra Atul
Published: May 2010

Increasing either genioglossus muscle activity (GG) or end-expiratory lung volume (EELV) improves airway patency but not sufficiently for adequate treatment of obstructive sleep apnea (OSA) in most patients. The mechanisms by which these variables alter airway collapsibility likely differ, with increased GG causing airway dilation, whereas increased EELV may stiffen the airway walls through caudal traction. We sought to determine whether the airway stabilizing effect of GG activation is enhanced when EELV is increased. To investigate this aim, 15 continuous positive airway pressure (CPAP)-treated OSA patients were instrumented with an epiglottic catheter, intramuscular GG-EMG electrodes, magnetometers, and a nasal mask/pneumotachograph. Subjects slept supine in a sealed, head-out plastic chamber in which the extra-thoracic pressure could be lowered (to raise EELV) while on nasal CPAP with a variable deadspace to allow CO2 stimulation (and GG activation). The pharyngeal critical closing pressure (PCRIT) was measured by sudden reduction of CPAP for three to five breaths each minute during non-rapid eye movement (NREM) sleep in 4 conditions: a) baseline, b) 500 ml increased EELV, c) 50% increased GG, and d) conditions b and c combined. PCRIT was found to be reduced from 2.2 ± 0.7 cmH2O at baseline to −1.0 ± 0.5 with increased EELV, 0.6 ± 0.7 with increased GG and −1.6 ± 0.7 when both variables were raised ( P < 0.001). The slope of the PCRIT curves remained unchanged in all conditions ( P = 0.05). However, the CPAP level at which flow limitation developed was lower in both increased EELV conditions ( P = 0.001). These findings indicate that while both increased GG and EELV improve airway collapsibility, the combination of both variables has little additional effect over increasing EELV alone.
Bifocal miniature toroidal shaped X-ray mirrors
Authors: Cornaby Sterling , Smilgies Detlef-M. , Bilderback Donald H.
Published: May 2010

We have fabricated a bifocal miniature toroidal mirror that horizontally and vertically focuses to two different locations to provide a smaller footprint of the beam for grazing-incidence wide-angle scattering (GIWAXS), while at the same time focusing the beam in the horizontal direction on the detector to further enhance the angular resolution. At CHESS we traditionally use glass single-bounce monocapillary optics for a wide range of X-ray experiments to get a fine X-ray beam of 5 to 20 μm. This miniature toroidal mirror was prepared by designing and fabricating an X-ray focusing capillary in which the sagittal and meridional focusing is decoupled and only a quadrant of the accepted annulus is used for focusing the beam. The mirror produced a 120 μm horizontal by 25 μm vertical focus at 50 mm from the tip of the optic and a 44 μm horizontal by 70 μm vertical focus at 150 mm from the tip of the optic.