Measurement of Wgamma and Zgamma production in pp collisions at square root s=1.96 TeV

The standard model predictions for Wgamma and Zgamma production are tested using an integrated luminosity of 200 pb(-1) of pp collision data collected at the Collider Detector at Fermilab. The cross sections are measured by selecting leptonic decays of the W and Z bosons, and photons with transverse energy ET>7 GeV that are well separated from leptons. The production cross sections and kinematic distributions for the Wgamma and Zgamma data are compared to SM predictions.

BCG vaccination scar associated with better childhood survival in Guinea-Bissau

BACKGROUND

Recent studies have suggested that Bacille Calmette-Guerin (BCG) vaccination may have a non-specific beneficial effect on infant survival and that a BCG scar may be associated with lower child mortality. No study has previously examined the influence of BCG vaccination on cause of death.

METHODS

Two cohorts (A and B) were used to describe the mortality pattern for children with and without BCG scar and to determine specific causes of death. In cohort A (n = 1813), BCG scar was assessed at 6 months of age and as previously described children with a BCG scar had lower mortality over the next 12 months than children with no BCG scar. In cohort B, 1617 children aged 3 months to 5 years of age had their BCG scar status assessed in a household-based survey and mortality was assessed during a 12-month period. Causes of death were determined by verbal autopsy (VA) and related to BCG scar status in a cause-specific hazard function.

RESULTS

Controlling for background factors associated with mortality, there was lower mortality for children with a BCG scar than without in cohort B, the mortality ratio (MR) being 0.45 (95% CI 0.21-0.96). Exclusion of children exposed to TB did not have any impact on the result. In a combined analysis of cohorts A and B, the MR was 0.43 (95% CI 0.28-0.65) controlling for background factors. There were no large differences in distribution of the five major causes of death (malaria, pneumonia, acute diarrhoea, chronic diarrhoea, and meningitis/encephalitis) according to BCG scar status in the two cohorts. Having a BCG scar significantly reduced the risk of death from malaria [MR 0.32 (95% CI 0.13-0.76)].

CONCLUSIONS

A BCG scar is a marker of better survival among children in countries with high child mortality. BCG vaccination may affect the response to several major infections including malaria.

Numerical simulation of two-phase partition chromatography in microchannels for moderated logP measurements

A finite element simulation has been used in order to study the partition chromatography process of one species between an aqueous mobile phase and an organic stationary phase located at the bottom of a rectangular microchannel. The transient model incorporates convection--diffusion of the species in the water phase coupled to the diffusion in the stationary organic phase by the way of the partition kinetics at the interface. The time evolution of the injected species concentration is analyzed versus the velocity of the mobile phase, the detecting position and the thickness of the stationary phase. The comparison of simulation results with both experimental data and analytical model confirm its validity. These simulations show that thin channels can be used to measure log P of molecules from their retention time. Finally, we have shown how the sample velocity can be optimized for a given geometry of the channel and diffusion coefficient of the species.

Hepatitis B vaccination associated with higher female than male mortality in Guinea-bissau: an observational study

OBJECTIVE

Studies from high mortality areas have suggested that diphtheria-tetanus-pertussis may be associated with an increase in the mortality of girls relative to boys. We therefore examined whether hepatitis B vaccine (HBV) was associated with sex-specific differences in mortality.

DESIGN

As part of a randomized trial of measles vaccine, a subcohort of 876 children was offered HBV at 7(1/2), 9 and 10(1/2) months of age. We examined whether this cohort differed in mortality rate and female-male mortality ratio compared with previous and subsequent birth cohort enrolled in the same trial.

SETTING

Four districts in Bissau, the capital of Guinea-Bissau.

SUBJECTS

Six annual birth cohorts of 8906 children registered in the study area and followed from 1(1/2) to 12 months of age between March 1995 and February 2001. Of these children, 6399 took part in a 2-dose measles vaccination trial; of those born between March 1996 and February 1997, 876 received HBV.

MAIN OUTCOME MEASURES

(1) The mortality rate ratio (MR) between 7(1/2) and 12 months and 1(1/2) and 7(1/2) months old children; (2) the female-male MR among trial children having received HBV plus measles vaccine or only measles vaccine.

RESULTS

In cohorts not receiving HBV, the MR for children 7(1/2)-12 and 1(1/2)-7(1/2) months of age was 0.97 "95% confidence interval (95% CI), 0.79-1.24", whereas the MR was 1.62 (95% CI 1.09-2.41) in the cohort receiving HBV at 7(1/2) months (test of homogeneity, P = 0.030). Among children enrolled in the measles vaccination trial, HBV-vaccinated children 7(1/2)-12 months of age had higher mortality than both prior and subsequent cohorts who had not received HBV (MR = 1.81; 95% CI 1.19-2.75), the difference being particularly strong for girls (MR=2.27; 95% CI 1.31-3.94). In the cohort who had received both HBV and measles vaccine, the female-male MR between 9 and 24 months of age was 2.20 (95% CI 1.07-4.54) compared with 0.96 (95% CI 0.70-1.32) in trial participants who had received measles vaccine only (test for homogeneity, P = 0.040). With longer follow-up, these tendencies remained the same.

CONCLUSIONS

These comparisons suggested changes in the mortality pattern after the introduction of HBV, particularly for girls. Hence in areas with high mortality, HBV may affect girls' and boys' susceptibility to infections differently.

Generation of mass tags by the inherent electrochemistry of electrospray for protein mass spectrometry

We present herein a review of our work on the on-line electrochemical generation of mass tags toward cysteine residues in peptides and proteins. Taking advantage of the inherent electrochemical nature of electrospray generated from a microfabricated microspray emitter, selective probes for cysteine were developed and tested for on-line nonquantitative mass tagging of peptides and proteins. The nonquantitative aspect of the covalent tagging thus allows direct counting of free cysteines in the mass spectrum of a biomolecule through additional adduct peaks. Several substituted hydroquinones were investigated in terms of electrochemical properties, and their usefulness for on-line mass tagging during microspray experiments were assessed with L-cysteine, peptides, and intact proteins. Complementarily, numerical simulations were performed to properly understand the respective roles of mass transport, kinetics of electrochemical-chemical reactions, and design of the microspray emitter in the mass tagging overall efficiency. Finally, the on-line electrochemical tagging of cysteine residues was applied to the analysis of tryptic peptides of purified model proteins for protein identification through peptide mass fingerprinting.

Search for doubly charged Higgs bosons decaying to dileptons in pp collisions at square root of s=1.96 TeV

We present the results of a search for doubly charged Higgs bosons (H+/-+/-) decaying to dileptons (ll(')) using approximately 240 pb(-1) of pp collision data collected by the CDF II experiment at the Fermilab Tevatron. In our search region, given by same-sign ll(') mass m(ll('))>80 GeV/c(2) (100 GeV/c(2) for ee channel), we observe no evidence for H+/-+/- production. We set limits on sigma(pp -->H++H---->l(+)l('+)l(-)l('-)) as a function of the mass of the H+/-+/- and the chirality of its couplings. Assuming exclusive same-sign dilepton decays, we derive lower mass limits on H(+/-+/-)(L) of 133, 136, and 115 GeV/c(2) in the ee, mumu, and emu channels, respectively, and a lower mass limit of 113 GeV/c(2) on H(+/-+/-)(R) in the mumu channel, all at the 95% confidence level.

Vaccination technique, PPD reaction and BCG scarring in a cohort of children born in Guinea-Bissau 2000-2002

The rates of positive tuberculin skin test (TST) reactions and BCG scarring after BCG vaccination vary between studies and populations. Tuberculin reactivity and BCG scarring may be related to better child survival in low-income countries. We therefore studied determinants for TST reaction and scarring in Guinea-Bissau. In a cohort of children born in suburban Bissau from March 2000 to July 2002, we assessed a Mantoux test with Purified protein derivative (PPD) (SSI, 2 T.U.) at 2 (2689 children), 6 (N=2148) and 12 months (N=1638) of age, and BCG scar was assessed at 2 (N=2698) and 6 months (N=2225) of age. In a subgroup of the children the vaccination technique was monitored by direct observation of post-vaccination wheal and route of administration. Three different types of BCG vaccine supplied by the local Extended Programme on Immunization were used. At 6 months of age the rate of PPD reactors (>1mm) after BCG vaccination was 25% and the rate of scarring was 89%. One BCG strain was associated with fewer PPD reactors (OR=0.54 (0.31-0.91)) and BCG scars (OR=0.13 (0.05-0.37)) and larger post-vaccination wheals produced more PPD reactions (OR 1.21 (95% CI 1.02-1.43)) and BCG scars (OR 1.66 (1.24-2.21)). In the multivariable analyses of BCG-vaccinated children assessed at 6 months of age, monitoring of vaccination technique and type of BCG vaccine were important. This was not changed by control for other determinants, including sex, season, vaccination place, birthplace, ethnic group, low birth weight, place of residence, education and civil status of mother. We reason that vaccination technique and BCG strain are important for PPD reaction and scarring in response to BCG vaccination. Considering that these responses are associated with better infant survival, the importance of monitoring vaccination technique and of different BCG strains should be evaluated with respect to infant mortality.

Oral polio vaccination and low case fatality at the paediatric ward in Bissau, Guinea-Bissau

Oral polio vaccine (OPV) and diphtheria-tetanus-pertussis (DTP) vaccines are given simultaneously in routine immunisation programmes in developing countries. It is therefore difficult to determine the separate effects of these vaccines on survival. We used the shortage of DTP vaccine in Bissau to examine the impact of OPV on the case fatality at the paediatric ward in Bissau. For 719 children less than 5 years of age whose vaccination card had been seen at admission and who had not yet received measles vaccine, having received OPV only was associated with a case fatality of 6% compared with 15% for children having received combined DTP and OPV vaccinations, the case fatality ratio (CFR) being 0.29 (95% confidence interval (CI) 0.11-0.77). Even if children fleeing the hospital were assumed to have died shortly after leaving the hospital, the case fatality would still be lower for children having received OPV only (CFR = 0.41; (95% CI 0.20-0.81)). The tendency was similar for children hospitalised with pneumonia, diarrhoea, and presumptive malaria. Control for background factors had no impact on the estimate. In areas with high mortality, OPV administered alone may have non-specific beneficial effects or DTP may have a negative effect for children who had received both DTP and OPV.

The social situation of motherless children in rural and urban areas of Guinea-Bissau

With the increasing prevalence of HIV infection and the high maternal mortality, orphans are a rapidly growing problem in Africa. However, few studies describe the social conditions of these children. Our study focuses on motherless children in urban and rural areas of Guinea-Bissau. A rural and an urban cohort of children (128 and 192, respectively) that had been followed by demographic surveillance since 1990 were identified and the relatives of these children interviewed. A control cohort of 808 individuals was also identified. Although orphan children remained disadvantaged, there were few differences between surviving motherless and control children in nutritional status, use of health care services, school attendance, quality of housing, and clothing. Motherless children moved more frequently and were more likely to live in small families, often with an older grandmother. The traditional extended family system appears to be capable of handling motherless children in a non-discriminatory fashion. However, the AIDS epidemic will continue to stress the extended family system and social services to the limit.

A flexible sample introduction method for polymer microfluidic chips using a push/pull pressure pump

A push/pull sample introduction method based on push/pull pressure flow for microfluidic systems (cross, double T and multichannel structures) is presented. This leads to well-defined and controllable sample plugs even when dealing with long channels. By tuning the relative push/pull pressure, it is shown that the size of the sample plug can effectively be controlled. Good signal reproducibility upon continued sample introduction and subsequent chip electrophoresis employing fluorescence detection is demonstrated for different chip geometries (i.e. short channels and long channels). Since the performance of the method is relatively insensitive to chip geometry, it is particularly useful for polymeric prototype microchips as tedious optimization is not required. Furthermore, the push/pull sample introduction is extended to multichannel chips thus demonstrating the possibilities of applying the methodology for realizing single chip high throughput sample analysis.

Measurement of the tt production cross section in pp collisions at sqrt[s]=1.96 TeV using dilepton events

We report a measurement of the tt production cross section using dilepton events with jets and missing transverse energy in pp collisions at a center-of-mass energy of 1.96 TeV. Using a 197+/-12 pb(-1) data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events. We compare the number of observed events and selected kinematical distributions with the predictions of the standard model and find good agreement. The combined result of the two techniques yields a tt production cross section of 7.0(+2.4)(-2.1)(stat)+1.6-1.1(syst)+/-0.4(lum) pb.

The introduction of diphtheria-tetanus-pertussis vaccine and child mortality in rural Guinea-Bissau: an observational study

BACKGROUND

and objective Previous studies from areas with high mortality in West Africa have not found diphtheria-tetanus-pertussis (DTP) vaccine to be associated with the expected reduction in mortality, a few studies suggesting increased mortality. We therefore examined mortality when DTP was first introduced in rural areas of Guinea-Bissau in 1984-1987. Setting Twenty villages in four regions have been followed with bi-annual examinations since 1979.

SUBJECTS

In all, 1657 children aged 2-8 months. Design Children were weighed when attending the bi-annual examinations and they were vaccinated whenever vaccines were available. DTP was introduced in the beginning of 1984, oral polio vaccine later that year. We examined mortality for children aged 2-8 months who had received DTP and compared them with children who had not been vaccinated because they were absent, vaccines were not available, or they were sick.

MAIN OUTCOME MEASURE

Mortality over the next 6 months from the day of examination for vaccinated and unvaccinated children.

RESULTS

Prior to the introduction of vaccines, children who were absent at a village examination had the same mortality as children who were present. During 1984-1987, children receiving DTP at 2-8 months of age had higher mortality over the next 6 months, the mortality rate ratio (MR) being 1.92 (95% CI: 1.04, 3.52) compared with DTP-unvaccinated children, adjusting for age, sex, season, period, BCG, and region. The MR was 1.81 (95% CI: 0.95, 3.45) for the first dose of DTP and 4.36 (95% CI: 1.28, 14.9) for the second and third dose. BCG was associated with slightly lower mortality (MR = 0.63, 95% CI: 0.30, 1.33), the MR for DTP and BCG being significantly inversed. Following subsequent visits and further vaccinations with DTP and measles vaccine, there was no difference in vaccination coverage and subsequent mortality between the DTP-vaccinated group and the initially DTP-unvaccinated group (MR = 1.06, 95% CI: 0.78, 1.44).

CONCLUSIONS

In low-income countries with high mortality, DTP as the last vaccine received may be associated with slightly increased mortality. Since the pattern was inversed for BCG, the effect is unlikely to be due to higher-risk children having received vaccination. The role of DTP in high mortality areas needs to be clarified.

Observation of the narrow state X(3872)-->J/psipi+pi- in pp collisions at sqaure root of s=1.96 TeV

We report the observation of a narrow state decaying into J/psipi+pi- and produced in 220 pb(-1) of p p-bar collisions at =1.96 Tesqaure root of sV in the CDF II experiment. We observe 730+/-90 decays. The mass is measured to be 3871.3+/-0.7(stat)+/-0.4(syst) MeV/c2, with an observed width consistent with the detector resolution. This is in agreement with the recent observation by the Belle Collaboration of the X(3872) meson.

Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests

Extracts from three species of the plant family Piperaceae, Piper nigrum [L.], Piper guineense [Schum & Thonn, and Piper tuberculatum [Jacq.], were tested for efficacy against insects from five orders. All three species contain isobutyl amides, plant secondary compounds that act as neurotoxins in insects. These materials are considered safe to mammals because Piper spp. were used for centuries for spice and medicinal purposes. When 24-h P. nigrum LC50 values were compared between common insect pests from eastern Canada and the northeastern United States, the most sensitive species in order of increasing lethal concentration were eastern tent caterpillar, Malacosoma americanum (F.) < European pine sawfly larvae, Neodiprion sertifer (Geoffroy) < spindle ermine moth larvae, Yponomeuta cagnagella [Hübner] < viburnum leaf beetle larvae, Pyrrhalta viburni [Paykull] < stripped cucumber beetle adults, Acalymma vittatum (F.) < Colorado potato beetle adults, Leptinotarsa decemlineata (Say) < Japanese beetle adults, Popillia japonica [Newman] < hairy chinch bug, Blissus leucopterus hirtis [Montandon]. The life stage tested was the point at which each species causes the greatest amount of damage to the host plant and the point at which most gardeners would likely choose to treat with a conventional synthetic insecticide. Greenhouse trials revealed that the pepper formulations also had a repellent activity, thus protecting plant leaves from 1) herbivory (lily leaf beetle, Lilioceris lilii [Scopoli], adults and larvae and stripped cucumber beetle adults) and 2) oviposition [European corn borer, Ostrinia nubilalis (Hübner)]. Combinations with other botanical extracts were additive at best in toxicity and repellent trials. Nontarget toxicity to beneficial invertebrates is a possibility because the P. nigrum LC50 for beneficial ladybird beetles was 0.2%. P. nigrum extracts can provide a reasonable level of control against lepidopteran and European pine sawfly larvae and also will work as a short-term repellent and feeding deterrent. It is recommended that the use of Piper extracts be restricted to small-scale spot treatments in residential areas where insect pest outbreaks have occurred.

Mothers may transmit RSV infection more easily or severely to sons than daughters: community study from Guinea-Bissau

Opposite gender transmission may increase the severity of certain infections. If infections transmitted from mother to son were more severe than from mother to daughter this might explain severe diseases among boys, particularly in small families with few individuals contributing to transmission. Among children from Guinea-Bissau, we tested whether mothers with recent respiratory syncytial virus exposure (positive IgM and IgA antibody responses) were more likely to have male than female children with respiratory syncytial virus antigen positive acute lower respiratory tract infection. Children with acute lower respiratory tract infection were identified at a paediatric clinic (n = 348), a health centre (n = 270), and in a community morbidity survey (n = 525), 14.2% (162/1143) having respiratory syncytial virus antigen. An equal number of boys and girls had acute lower respiratory tract infection, but boys were more likely to have respiratory syncytial virus detected (prevalence ratio = 1.36 (1.01-1.81)), this difference being particularly marked in the rainy season. With recent respiratory syncytial virus exposure of mother, boys were twice as likely to have respiratory syncytial virus detected (prevalence ratio = 2.04 (1.18-3.53)), the difference being marked in the rainy season. There was no gender difference in respiratory syncytial virus infection among children of RSV negative mothers. We conclude that mothers may transmit respiratory syncytial virus more easily or severely to sons.

Search for B0s-->micro+micro- and B0d-->micro+micro- decays in pp collisions at square root s = 1.96 TeV

We report on a search for B(0)(s)-->micro(+)micro(-) and B(0)(d)-->micro(+)micro(-) decays in pp collisions at square root of s=1.96 TeV using 171 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The decay rates of these rare processes are sensitive to contributions from physics beyond the standard model. One event survives all our selection requirements, consistent with the background expectation. We derive branching ratio limits of B(B(0)(s)-->micro(+)micro(-))<5.8x10(-7) and B(B(0)(d)-->micro(+)micro(-))<1.5x10(-7) at 90% confidence level.

Microfluidic systems in proteomics

We present the state-of-the-art in miniaturized sample preparation, immunoassays, one-dimensional and multidimensional analyte separations, and coupling of microdevices with electrospray ionization-mass spectrometry. Hyphenation of these different techniques and their relevance to proteomics will be discussed. In particular, we will show that analytical performances of microfluidic analytical systems are already close to fulfill the requirements for proteomics, and that miniaturization results at the same time in a dramatic increase in analysis throughput. Throughout this review, some examples of analytical operations that cannot be achieved without microfluidics will be emphasized. Finally, conditions for the spreading of microanalytical systems in routine proteomic labs will be discussed.

Low birth weight infants and Calmette-Guérin bacillus vaccination at birth: community study from Guinea-Bissau

BACKGROUND

In developing countries, low birth weight (LBW) children are often not vaccinated with Calmette-Guérin bacillus (BCG) at birth. Recent studies have suggested that BCG may have a nonspecific beneficial effect on infant mortality. We evaluated the consequences of not vaccinating LBW children at birth in Guinea-Bissau.

METHODS

Between 1989 and 1999, 7138 children born at the central hospital had a birth weight registered. We assessed BCG coverage until 3 years of age. Data on tuberculin skin test (TST) for 297 children and BCG scar for 1319 children in the study population were reanalyzed for differences between normal birth weight (NBW) children and LBW children. We assessed the effect of early BCG vaccination on mortality to 12 months of age.

RESULTS

Among LBW children there were 1.5- to 3-fold more unvaccinated individuals than among NBW children up to 4 months of age. There was no overall difference between LBW and NBW children in TST or BCG scarring; LBW children vaccinated early may have had slightly reduced reactions to tuberculin. Among 845 LBW children, 182 had received BCG within the first week of life. Controlling for background factors and censoring at first diphtheria-tetanuspertussis vaccination, measles vaccination or at 6 months of age (whichever came first), the mortality rate ratio for BCG-vaccinated versus -unvaccinated LBW children was 0.17 (95% confidence interval, 0.06-0.49), with an even stronger effect for LBW children vaccinated in the first week of life (mortality rate ratio, 0.07; 95% confidence interval, 0.01-0.62).

CONCLUSIONS

The policy of not vaccinating with BCG at birth had a negative impact on vaccination coverage for LBW children. Early BCG vaccination had no large negative impact on TST and BCG scarring. Mortality was lower for BCG-vaccinated than for unvaccinated LBW children controlling for available background factors. BCG vaccination of LBW children may have a beneficial effect on survival that cannot be explained by protection against tuberculosis. Future studies should examine possible adverse effects from equalizing BCG policy for LBW and NBW children.