Search for [corrected] B0(s) --> mu+ mu- and B0(d) [corrected] --> mu + mu- decays in pp collisions with CDF II

We report on a search for B0(s) --> mu+ mu- and B0(d) --> mu + mu- decays in pp collisions at square root(s) = 1.96 TeV using 364 pb(-1) of data collected by the CDF II detector at the Fermilab Tevatron Collider. After applying all selection requirements, we observe no candidates inside the B0(s) or B0(d) mass windows. The resulting upper limits on the branching fractions are B(B0(s) --> mu+ mu-) < 1.5 x 10(-7) and B(B0(d) --> mu+ mu-) < 3.9 x 10(-8) at 90% confidence level.

Pre-equilibrium capillary zone electrophoresis or frontal analysis: Advantages of plateau peak conditions in affinity capillary electrophoresis

The feasibility of using the affinity CE methodologies pre-equilibrium CZE and CE frontal analysis was tested on interaction systems exhibiting rapid on-and-off kinetics. Experimentally, the methodologies differ only with respect to the volume of sample introduced into the capillary. Pre-equilibrium CZE has been considered amendable to interactions with slow on-and-off kinetics only; however, it has recently been applied in studies of interactions with fast on-and-off kinetics. The effect of varying the sample volume introduced hydrodynamically into the capillary on the apparent degree of complexation was studied. For two different binding systems, the fraction of free analyte was found to be overestimated using pre-equilibrium CZE as compared to volumes providing plateau peak conditions as used with frontal analysis. Results indicate that frontal analysis conditions lead to more robust binding assays and thus more reliable data. The validity of data obtained by pre-equilibrium CZE may be low, thus the use of an experimental setup providing plateau peaks is highly recommended. It is suggested that the effect of altering the sample volume on the degree of binding should be investigated as part of method development and validation.

Dynamic protein adsorption in microchannels by "stop-flow" and continuous flow

This work addresses two ways of loading proteins on microchannel surfaces for immunoassay applications: the "stop-flow" and the continuous flow processes. The "stop-flow" method consists of successive static incubation periods where the bulk solution depletes upon the adsorption process. In the present paper, a multi-step "stop-flow" protein coating is studied and compared to a coating under continuous flow conditions. For the "stop-flow", a non-dimensional parameter is here introduced, indicating the adsorbing capacity of the system, by which it is possible to calculate the number of loads necessary to reach the optimum coverage. For the continuous flow, the effects on the adsorption of the kinetic rates, flow velocity and wall capacity have been considered. This study shows the importance of a careful choice of the fluid velocity to minimise the sample waste. For diffusion controlled and kinetics controlled processes, two flow velocity criteria are provided in order to obtain the best possible coverage, with the same amount of sample as with the "stop-flow".

Search for new physics using high-mass tau pairs from 1.96 TeV pp collisions

We present the results of a search for anomalous resonant production of tau lepton pairs with large invariant mass, the first such search using the CDF II Detector in Run II of the Tevatron pp collider. Such anomalous production could arise from various new physics processes. In a data sample corresponding to 195 pb(-1) of integrated luminosity we predict 2.8+/-0.5 events from standard model background processes and observe 4. We use this result to set limits on the production of heavy scalar and vector particles decaying to tau lepton pairs.

Measurement of B(t --> Wb)/B(t--> Wq) at the collider detector at fermilab

We present a measurement of the ratio of top-quark branching fractions R = B(t --> Wb)/B(t --> Wq), where q can be a b, s, or a d quark, using lepton-plus-jets and dilepton data sets with an integrated luminosity of approximately 162 pb(-1) collected with the Collider Detector at Fermilab during Run II of the Tevatron. The measurement is derived from the relative numbers of tt events with different multiplicity of identified secondary vertices. We set a lower limit of R > 0.61 at 95% confidence level.

Salt removal during Off-Gel electrophoresis of protein samples

The Off-Gel technology was recently described for protein fractionation in a solution placed on top of an immobilized pH gradient gel. In addition, this process was found to remove salts from the biological samples to analyze. This desalting effect is studied experimentally in a conductometric prototype cell. A simplified analytical model is developed to understand this process and a good agreement is found with the conductivity measurements. To illustrate the desalting of a biological sample, a 1 mg.mL(-1) solution of beta-lactoglobulin A in 0.1 M NaCl is subjected to electrophoresis in a single compartment Off-Gel cell. The analysis of the resulting sample by ESI-MS demonstrates the effective removal of salt. A finite element diffusion-migration model is also used to illustrate how the nonuniformity of the electric field in the cell, associated with the salt migration, can slow down the desalting process.

Search for long-lived doubly charged Higgs bosons in pp collisions at sqrt[s] = 1.96 TeV

We present a search for long-lived doubly charged Higgs bosons (H(+/- +/-)), with signatures of high ionization energy loss and muonlike penetration. We use 292 pb(-1) of data collected in pp collisions at sqrt[s] = 1.96 TeV by the CDF II detector at the Fermilab Tevatron. Observing no evidence of long-lived doubly charged particle production, we exclude H(+/- +/-)(L) and H(+/- +/-)(R) bosons with masses below 133 GeV/c(2) and 109 GeV/c(2), respectively. In the degenerate case we exclude H(+/- +/-) mass below 146 GeV/c(2). All limits are quoted at the 95% confidence level.

Relation between patients' and physicians' severity assessment of occupational hand eczema

BACKGROUND

Severity assessment of occupational hand eczema (OHE) is important not only in clinical settings but also in research. Questionnaires with self-rated assessment of severity may be an attractive tool for assessing severity because of their cost efficiency in comparison with expensive clinical examinations.

OBJECTIVES

To evaluate the relation between self-rated severity and severity assessment based on standardized medical certificates issued by dermatologists in a population of patients with OHE.

METHODS

Between October 2001 and November 2002 (58 weeks) we identified all new cases of recognized OHE from the Danish National Board of Industrial Injuries (DNBII) registry. Each patient was examined by a dermatologist, who issued a standardized medical certificate. The severity assessment in the DNBII registry was based on this medical certificate, which comprised information on morphology and extent of eczema, and frequency of eruptions. All participants received a self-administered questionnaire and were asked to classify severity of their OHE on a visual analogue scale from 0 to 10. The relation between DNBII-assessed and self-rated severity was illustrated by a receiver operating characteristic analysis.

RESULTS

Of 758 patients included in the study, 621 returned the questionnaire and 602 (79%) provided information on self-rated severity. The proportion of severe cases was significantly higher among patients' assessments compared with the rating by the DNBII. Almost 18% were categorized as severe cases by the DNBII while 40% of patients had assessed themselves as having severe eczema. The optimal cut-off point had a sensitivity and specificity of self-rated severity according to the DNBII assessment of 65% and 66%, respectively. The positive predictive value was 29% and the negative predictive value was 90%.

CONCLUSIONS

The low positive predictive value suggests major differences in the criteria for self-rated severity vs. DNBII-rated severity. We recommend researchers to include ratings from both patients and physicians in future investigations of severity. The methods may address different aspects of OHE.

Evidence for B0 s-->phiphi decay and measurements of branching ratio and A(CP) for B+ -->phiK+

We present the first evidence of charmless decays of the B(0)(s) meson, the decay B(0)(s)--> phiphi, and a measurement of the branching ratio BR(B(0)(s)--> phiphi) using 180 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron collider. In addition, the BR and direct CP asymmetry for the B+-->phiK+ decay are measured. We obtain BR(B(0)(s)--> phiphi)=[14(+6)(-5)(stat)+/-6(syst)] x 10(-6), BR(B+-->phiK+)=[7.6+/-1.3(stat)+/-0.6(syst)] x 10(-6), and A(CP)(B+-->phiK+)= -0.07+/-0.17(stat)+0.03 / -0.02(syst). Both decays are governed in the standard model by second order (penguin) b-->s(-)ss amplitudes.

Search for anomalous kinematics in tt dilepton events at CDF II

We report on a search for anomalous kinematics of tt dilepton events in pp collisions at square root of s=1.96 TeV using 193 pb(-1) of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy, and we find that the probability of obtaining a data sample less consistent with the SM than what is observed is 1.0%-4.5%.

Measurement of the cross section for prompt diphoton production in pp collisions at square root of s=1.96 TeV

We report a measurement of the rate of prompt diphoton production in pp collisions at square root of s=1.96 TeV using a data sample of 207 pb(-1) collected with the upgraded Collider Detector at Fermilab. The background from nonprompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.

Measurement of the W(+)W(-) production cross section in pp collisions at square root[s]=1.96 TeV using dilepton events

We present a measurement of the W(+)W(-) production cross section using 184 pb(-1) of p(p) collisions at a center-of-mass energy of 1.96 TeV collected with the Collider Detector at Fermilab. Using the dilepton decay channel W(+)W(-)-->l(+)nul(-), where the charged leptons can be either electrons or muons, we find 17 candidate events compared to an expected background of 5.0(+2.2)(-0.8) events. The resulting W(+)W(-) production cross-section measurement of sigma(pp-->W(+)W(-))=14.6(+5.8)(-5.1)(stat)(+1.8)(-3.0)(syst) +/- 0.9(lum) pb agrees well with the standard model expectation.

Childhood mortality after oral polio immunisation campaign in Guinea-Bissau

Though previous studies have suggested a non-specific beneficial effect of oral polio vaccine (OPV), there has been no evaluation of the mortality impact of national polio immunization days. On the other hand, studies examining the effect of OPV and diphtheria-tetanus-pertussis (DTP) vaccines, which are usually administered together in routine immunisation programmes in low-income countries, have found no beneficial or even a negative effect on infant survival. In 1998, we used the opportunity of two national immunisation days to examine the impact of OPV administered alone on survival for the 6103 children less than 5 years of age in the Bandim Health Project's study area in Guinea-Bissau. Survival was ascertained through regular surveillance from March 1998 until the beginning of the war on June 7, 1998, the end of 1998, or the end of 1999, respectively. The child register was linked with a register for the only paediatric ward in Bissau to determine the risk of hospitalisations. Among children under 5 years of age, 82% had received 1 or 2 doses of polio vaccines during the campaign. Though polio vaccination during the campaign was associated with slightly lower mortality, this difference was not significant for all children under 5 years of age (mortality ratio (MR)=0.46 (0.18-1.15)). However, oral polio vaccination was associated with a beneficial effect for children under 6 months of age at the time of the campaign, the mortality ratio being 0.09 (95% CI 0.01-0.85) in the 3 months before the war controlling for significant background factors, including routine immunizations, antenatal consultations, and arm circumference. The polio-vaccinated children aged 0-5 months had fewer hospitalisations than children who had not been polio vaccinated (RR=0.27 (0.10-0.76)). With longer follow-up to December 1998 or December 1999, the difference in mortality gradually disappeared, the MR for polio-vaccinated children being 0.61 (0.32-1.14) and 0.83 (0.51-1.34), respectively. Among children aged 6-59 months of age, measles vaccine was associated with a 56% reduction in mortality (MR=0.44 (0.28-0.69)) and no effect of oral polio vaccine was measurable in this age group. The effect of polio vaccine among children less than 6 months of age could be due to selection bias but might also represent a non-specific beneficial immune stimulation and there is nothing to suggest that OPV might have a negative effect on infant survival. Studies of the possible non-specific effects of oral polio vaccine are warranted before OPV is withdrawn.

Acute lower respiratory tract infections and respiratory syncytial virus in infants in Guinea-Bissau: a beneficial effect of BCG vaccination for girls community based case-control study

Among measles unvaccinated infants in Guinea-Bissau, we tested whether case infants with acute lower respiratory tract infection (ALRI), especially ALRI caused by respiratory syncytial virus (RSV), were more likely to be Bacille Calmette Guerin (BCG)-unvaccinated and to have no scar after BCG vaccination than were control infants without symptoms of ALRI. Three hundred and eighty-six case infants with ALRI were identified at a paediatric clinic (N=84), a health centre (N=82), and in a community morbidity surveillance system (N=220). Control infants were matched on sex, age, and district and were also measles unvaccinated. In ALRI case infants, the adjusted OR of being BCG unvaccinated was 2.87 (1.31-6.32), 1.72 (0.48-6.19) in boys and 4.45 (1.48-13.4) in girls. Among BCG vaccinated ALRI case infants, the adjusted OR of having no BCG scar was 1.54 (0.86-2.75), 0.93 (0.45-1.91) in boys and 2.70 (1.21-6.02) in girls. In ALRI case infants with RSV infection, similar trends were observed. BCG vaccination may have a non-targeted protective effect against ALRI, the effect being most marked in girls.

Measurement of partial widths and search for direct CP violation in D0 meson decays to K-K+ and pi-pi+

We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and pi(-)pi(+) decays of D0 mesons produced in pp collisions at sqrt[s]=1.96 TeV. We use a sample of 2x10(5) D(*+)-->D0pi(+) (and charge conjugate) decays with the D0 decaying to K-pi(+), K-K+, and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D0-->K-K+)/Gamma(D0-->K-pi(+))=0.0992+/-0.0011+/-0.0012, Gamma(D0-->pi(-)pi(+))/Gamma(D0-->K-pi(+))=0.035 94+/-0.000 54+/-0.000 40, A(CP)(K-K+)=(2.0+/-1.2+/-0.6)%, and A(CP)(pi(-)pi(+))=(1.0+/-1.3+/-0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic.

Complexation between low-molecular-weight cationic ligands and negatively charged polymers as studied by capillary electrophoresis frontal analysis

The potential of using capillary electrophoresis frontal analysis for the study of low-molecular-weight ligand-polyelectrolyte interactions was assessed. The interaction of the ligands 1-propylpyridinium bromide, 2-propylisochinolinium bromide, and paraquat with the polymer dextran sulfate was investigated as a function of polymer concentration and ionic strength of the buffer solution. Linear binding isotherms were obtained and association constants were determined. The complex formation was independent of the dextran sulfate concentration at low ionic strength. Ligand-polyelectrolyte interactions were strongly dependent on the ionic strength. The interaction of the divalent cation paraquat with the dextran sulfate was much stronger than the interactions of the monovalent cationic ligands with the polyelectrolyte. The binding data obtained were in accord with results obtained by equilibrium dialysis. Capillary electrophoresis frontal analysis has the potential to become a valuable tool for characterization of ligand-polyelectrolyte interactions in drug design as well as in other areas.

Measurement of the lifetime difference between Bs mass eigenstates

We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.05(+0.16)(-0.13) +/- 0.02) ps and tau(H) = (2.07(+0.58)(-0.46) +/- 0.03) ps. Expressed in terms of the difference DeltaGamma(s) and average Gamma(s), of the decay rates of the two eigenstates, the results are DeltaGamma(s)/Gamma(s) = (65(+25)(-33) +/- 1)% and DeltaGamma(s) = (0.47(+0.19)(-0.24) +/- 0.01) ps(-1).

Search for excited and exotic electrons in the egamma decay channel in pp collisions at sqrt[s] = 1.96 TeV

We present a search for excited and exotic electrons (e(*)) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb(-1) of data collected in pp collisions at sqrt[s] = 1.96 TeV with the Collider Detector at Fermilab II detector. No signal above standard model expectation is seen for associated ee(*) production. We discuss the e(*) sensitivity in the parameter space of the excited electron mass M(e(*)) and the compositeness energy scale Lambda. In the contact interaction model, we exclude 132 GeV/c(2)<M(e(*))<879 GeV/c(2) for Lambda = M(e(*)) at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 GeV/c(2) < M(e(*)) < 430 GeV/c(2) at 95% C.L. for the phenomenological coupling f/Lambda approximately 10(-2) GeV-1.

Routine vaccinations associated with divergent effects on female and male mortality at the paediatric ward in Bissau, Guinea-Bissau

Several studies have suggested that routine childhood immunisations may have non-specific effects on mortality. To examine which disease categories might be affected, we investigated whether immunisation status had an impact on the case fatality for hospitalised children. Between 1990 and 1996, the Bandim Health Project maintained a register of all children from the study area hospitalised at the paediatric ward of the central hospital in Bissau, Guinea-Bissau. The study included 2079 hospitalised children aged 1.5-17 months coming from the Bandim study area. Among children whose vaccination card had been seen at admission, the case fatality ratio for measles-vaccinated children versus measles-unvaccinated children was 0.51 (0.27-0.98), the beneficial effect being significantly stronger for girls than for boys (test of interaction, p=0.050). The protective effect of measles vaccine remained unchanged when hospitalised measles cases were excluded from the analysis (0.49 (0.26-0.94)). The effect of measles vaccine was strongest for children with pneumonia (MR=0.28 (0.07-0.91)) and presumptive malaria (MR=0.40 (0.13-1.18)). For measles-vaccinated children, the female to male case fatality ratio was 0.54 (0.28-0.97). Among children having received diphtheria-tetanus-pertussis (DTP) and oral polio (OPV) as the last vaccines, girls had higher case fatality than boys, the mortality ratio being 1.63 (1.03-2.59). The female to male ratios were significantly inversed for DTP and OPV versus measles vaccine (test of interaction, p=0.003). These results remained unchanged if 1-month post-discharge deaths were included in the analysis, and in multivariate analyses controlling for determinants of mortality. In conclusion, measles vaccine was associated with reduced mortality from diseases other than measles, the beneficial effect being stronger for girls than for boys. On the other hand, DTP and OPV vaccine were associated with higher case fatality for girls than for boys. Understanding the divergent non-specific effects of common vaccines may contribute to better child survival in developing countries.

First measurements of inclusive W and Z cross sections from run II of the fermilab tevatron collider

We report the first measurements of inclusive W and Z cross sections times leptonic branching ratios for pp collisions at square root[s]=1.96 TeV, based on their decays to electrons and muons. The data correspond to an integrated luminosity of 72 pb(-1) recorded with the CDF detector at the Fermilab Tevatron. We test e-mu universality in W decays, and we measure the ratio of leptonic W and Z rates from which the leptonic branching fraction B(W-->lnu) can be extracted as well as an indirect value for the total width of the W and the Cabibbo-Kobayashi-Maskawa matrix element, |V(cs)|.

Protein adsorption in static microsystems: effect of the surface to volume ratio

A numerical model for the adsorption kinetics of proteins on the walls of a microchannel has been developed using the finite element method (FEM) to address the coupling with diffusion phenomena in the restricted microchannel volume. Time evolutions of the concentration of one species are given, both in solution and on the microchannel walls. The model illustrates the adsorption limitation sometimes observed when the microdimensions of these systems induce a global depletion of the bulk solution. A new non-dimensional parameter is introduced to predict the final value of the coverage of any microsystem under static adsorption. A working curve and a criteria (h/K[Gamma](max) > 10) are provided in order to choose, for given adsorption characteristics, the value of the volume-to-surface ratio (i.e. the channel height h) avoiding depletion effects on the coverage (relative coverage greater than 90% of the theoretical one). Simulations were compared with confocal microscopy measurements of IgG antibody adsorption on the walls of a PET microchannel. The fit of the model to the experimental data show that the adsorption is under apparent kinetic control.