2,076 research outputs found
Antibiotic Therapy and the Gut Microbiome:Investigating the Effect of Delivery Route on Gut Pathogens
The contribution of the gut microbiome to human health has long been established, with normal gut microbiota conferring protection against invasive pathogens. Antibiotics can disrupt the microbial balance of the gut, resulting in disease and the development of antimicrobial resistance. The effect of antibiotic administration route on gut dysbiosis remains under-studied to date, with conflicting evidence on the differential effects of oral and parenteral delivery. We have profiled the rat gut microbiome following treatment with commonly prescribed antibiotics (amoxicillin and levofloxacin), via either oral or intravenous administration. Fecal pellets were collected over a 13-day period and bacterial populations were analyzed by 16S rRNA gene sequencing. Significant dysbiosis was observed in all treatment groups, regardless of administration route. More profound dysbiotic effects were observed following amoxicillin treatment than those with levofloxacin, with population richness and diversity significantly reduced, regardless of delivery route. The effect on specific taxonomic groups was assessed, revealing significant disruption following treatment with both antibiotics. Enrichment of a number of groups containing known gut pathogens was observed, in particular, with amoxicillin, such as the family Enterobacteriaceae. Depletion of other commensal groups was also observed. The degree of dysbiosis was significantly reduced toward the end of the sampling period, as bacterial populations began to return to pretreatment composition. Richness and diversity levels appeared to return to pretreatment levels more quickly in intravenous groups, suggesting convenient parenteral delivery systems may have a role to play in reducing longer term gut dysbiosis in the treatment of infection
HIV-related travel restrictions: trends and country characteristics
Introduction: Increasingly, HIV-seropositive individuals cross international borders. HIV-related restrictions on entry, stay, and residence imposed by countries have important consequences for this mobile population. Our aim was to describe the geographical distribution of countries with travel restrictions and to examine the trends and characteristics of countries with such restrictions. Methods: In 2011, data presented to UNAIDS were used to establish a list of countries with and without HIV restrictions on entry, stay, and residence and to describe their geographical distribution. The following indicators were investigated to describe the country characteristics: population at mid-year, international migrants as a percentage of the population, Human Development Index, estimated HIV prevalence (age: 15–49), presence of a policy prohibiting HIV screening for general employment purposes, government and civil society responses to having non-discrimination laws/regulations which specify migrants/mobile populations, government and civil society responses to having laws/regulations/policies that present obstacles to effective HIV prevention, treatment, care, and support for migrants/mobile populations, Corruption Perception Index, and gross national income per capita. Results: HIV-related restrictions exist in 45 out of 193 WHO countries (23%) in all regions of the world. We found that the Eastern Mediterranean and Western Pacific Regions have the highest proportions of countries with these restrictions. Our analyses showed that countries that have opted for restrictions have the following characteristics: smaller populations, higher proportions of migrants in the population, lower HIV prevalence rates, and lack of legislation protecting people living with HIV from screening for employment purposes, compared with countries without restrictions. Conclusion: Countries with a high proportion of international migrants tend to have travel restrictions – a finding that is relevant to migrant populations and travel medicine providers alike. Despite international pressure to remove travel restrictions, many countries continue to implement these restrictions for HIV-positive individuals on entry and stay. Since 2010, the United States and China have engaged in high profile removals. This may be indicative of an increasing trend, facilitated by various factors, including international advocacy and the setting of a UNAIDS goal to halve the number of countries with restrictions by 2015
Differences in reading background brought to first grade.
Thesis (Ed.M.)--Boston Universit
Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA
Inclusive photoproduction of D*+- mesons has been measured for photon-proton
centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality
Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of
37 pb^-1. Total and differential cross sections as functions of the D*
transverse momentum and pseudorapidity are presented in restricted kinematical
regions and the data are compared with next-to-leading order (NLO) perturbative
QCD calculations using the "massive charm" and "massless charm" schemes. The
measured cross sections are generally above the NLO calculations, in particular
in the forward (proton) direction. The large data sample also allows the study
of dijet production associated with charm. A significant resolved as well as a
direct photon component contribute to the cross section. Leading order QCD
Monte Carlo calculations indicate that the resolved contribution arises from a
significant charm component in the photon. A massive charm NLO parton level
calculation yields lower cross sections compared to the measured results in a
kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure
Measurement of Jet Shapes in Photoproduction at HERA
The shape of jets produced in quasi-real photon-proton collisions at
centre-of-mass energies in the range GeV has been measured using the
hadronic energy flow. The measurement was done with the ZEUS detector at HERA.
Jets are identified using a cone algorithm in the plane with a
cone radius of one unit. Measured jet shapes both in inclusive jet and dijet
production with transverse energies GeV are presented. The jet
shape broadens as the jet pseudorapidity () increases and narrows
as increases. In dijet photoproduction, the jet shapes have been
measured separately for samples dominated by resolved and by direct processes.
Leading-logarithm parton-shower Monte Carlo calculations of resolved and direct
processes describe well the measured jet shapes except for the inclusive
production of jets with high and low . The observed
broadening of the jet shape as increases is consistent with the
predicted increase in the fraction of final state gluon jets.Comment: 29 pages including 9 figure
Randomized controlled trial and economic evaluation of nurse-led group support for young mothers during pregnancy and the first year postpartum versus usual care
Background Child maltreatment is a significant public health problem. Group Family Nurse Partnership (gFNP) is a new intervention for young, expectant mothers implemented successfully in pilot studies. This study was designed to determine the effectiveness and cost effectiveness of gFNP in reducing risk factors for maltreatment with a potentially vulnerable population.
Methods A multi-site randomized controlled parallel-arm trial and prospective economic evaluation was conducted, with allocation via remote randomization (minimization by site, maternal age group) to gFNP or usual care. Participants were expectant mothers aged <20 with at least one live birth, or 20–24 with no live births and with low educational qualifications. Data from maternal interviews at baseline and when infants were two, six and 12 months, and video recording at 12 months, were collected by researchers blind to allocation. Cost information came from weekly logs completed by gFNP family nurses and other service delivery data reported by participants. Primary outcomes measured at 12 months were parenting attitudes (Adult- Adolescent Parenting Index, AAPI-2) and maternal sensitivity (CARE index). The economic evaluation was conducted from a UK NHS and personal social services perspective with cost-effectiveness expressed in terms of incremental cost per quality-adjusted life year (QALY) gained. Main analyses were intention to treat with additional complier average causal effects (CACE) analyses.
Results Between August 2013 and September 2014, 492 names of potential participants were received of whom 319 were eligible and 166 agreed to take part, 99 randomly assigned to receive gFNP and 67 to usual care. There were no between-arms differences in AAPI-2 total (7·5/10 in both, SE 0.1), difference adjusted for baseline, site and maternal age-group 0·06 (95% CI -0·15 to 0·28, p=0·59) or CARE Index (intervention 4·0 (SE 0·3); control 4·7(SE 0·4); difference adjusted for site and maternal age-group -0·68; 95% CI -1·62 to 0·16, p=0·25) scores. The probability that gFNP is cost-effective based on the QALY measure did not exceed 3%.
Conclusions The trial did not support gFNP as a means of reducing the risk of child maltreatment in this population but slow recruitment adversely affected group size and consequently delivery of the intervention
Measurement of the F2 structure function in deep inelastic ep scattering using 1994 data from the ZEUS detector at HERA
We present measurements of the structure function \Ft\ in e^+p scattering at HERA in the range 3.5\;\Gevsq < \qsd < 5000\;\Gevsq. A new reconstruction method has allowed a significant improvement in the resolution of the kinematic variables and an extension of the kinematic region covered by the experiment. At \qsd < 35 \;\Gevsq the range in x now spans 6.3\cdot 10^{-5} < x < 0.08 providing overlap with measurements from fixed target experiments. At values of Q^2 above 1000 GeV^2 the x range extends to 0.5. Systematic errors below 5\perc\ have been achieved for most of the kinematic urray, W
Measurement of the Diffractive Cross Section in Deep Inelastic Scattering using ZEUS 1994 Data
The DIS diffractive cross section, , has been measured in the mass range GeV for c.m. energies GeV and photon virtualities to 140 GeV. For fixed and , the diffractive cross section rises rapidly with , with corresponding to a -averaged pomeron trajectory of \bar{\alphapom} = 1.127 \pm 0.009 (stat)^{+0.039}_{-0.012} (syst) which is larger than \bar{\alphapom} observed in hadron-hadron scattering. The dependence of the diffractive cross section is found to be the same as that of the total cross section for scattering of virtual photons on protons. The data are consistent with the assumption that the diffractive structure function factorizes according to \xpom F^{D(3)}_2 (\xpom,\beta,Q^2) = (x_0/ \xpom)^n F^{D(2)}_2(\beta,Q^2). They are also consistent with QCD based models which incorporate factorization breaking. The rise of \xpom F^{D(3)}_2 with decreasing \xpom and the weak dependence of on suggest a substantial contribution from partonic interactions
Measurement of Elastic Photoproduction at HERA
The production of mesons in the reaction () at a median of $10^{-4} \
\rm{GeV^2}\phid\sigma/dt0.1<|t|<0.5 \ \rm{GeV^2}60 <
W < 80 \ \rm{GeV}\sigma_{\gamma p
\rightarrow \phi p} = 0.96 \pm 0.19^{+0.21}_{-0.18}\rm{\mu b}\sigma_{\gamma p \rightarrow
\phi p}t\phis\phi$ photoproduction are
compatible with those of a soft diffractive process.Comment: 23 pages, including 6 post script figure
Comparison of ZEUS data with standard model predictions for scattering at high and
Using the ZEUS detector at HERA, we have studied the reaction e(+)p --> e(+)X for Q(2) > 5000 GeV2 with a 20.1 pb(-1) data sample collected during the years 1993 to 1996. For Q(2) below 15000 GeV2, the data are in good agreement with Standard Model expectations. For Q(2) > 35000 GeV2. two events are observed while 0.145 +/- 0.013 events are expected, A statistical analysis of a large ensemble of simulated Standard Model experiments indicates that with probability 6.0%, an excess at least as unlikely as that observed would occur above some Q(2) cut. For x > 0.55 and y > 0.75, four events are observed where 0.91 +/- 0.08 events are expected, A statistical analysis of the two-dimensional distribution of the events in x and y yields a probability of 0.72% for the region x > 0.55 and y > 0.25 and a probability of 7.8% for the entire Q(2) > 5000 GeV2 data sample. The observed excess above Standard Model expectations is particularly interesting because it occurs in a previously unexplored kinematic region
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