The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300–318 GeV using an integrated luminosity of 120 pb
...−1. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range
0.3
<
p
T
/
M
<
0.7
. The particle rates have been extracted and interpreted in terms of the coalescence model. The (anti)deuteron production yield is smaller than the (anti)proton yield by approximately three orders of magnitude, consistent with the world measurements.
Treatment of 1,2-di(thien-2-yl)ethanone with aqueous 75% (v/v) sulfuric acid gives a dimer in which the units are linked head-to-head via a thiophene–tetrahydrothiophene bond.
Graphic
To examine HIV-1-related mortality and demographic impact in a high HIV prevalence rural district of Uganda.
One-year follow-up (1990-1991) in a population-based rural cohort.
Annual enumeration of ...all consenting residents of 1945 households in 31 randomly selected community clusters in Rakai District. Subjects provided yearly HIV serological samples, behavioral and health information.
Mortality in HIV-infected and uninfected persons.
Mortality among HIV-seropositive adults aged > or = 15 years of 118.4 per 1000 person-years (PY) was substantially higher than in HIV-seronegative adults 12.4 per 1000 PY; relative risk (RR), 9.5; 95% confidence interval (CI), 6.0-14.9. Infant mortality among offspring of HIV-infected mothers was almost double that for uninfected women (210 compared with 111 per 1000 live births; RR, 1.9; 95% CI, 1.0-3.5). Adult HIV-related mortality was associated with HIV prevalence and, in this cohort, with higher education, non-agricultural occupation and residence in roadside trading centers. We estimate that adult HIV prevalence in the district is 13% and adult HIV attributable mortality 52%. For all ages combined, district HIV attributable mortality is 28%.
HIV is the leading cause of adult death in Rakai. Its effects on mortality are particularly marked in the most economically active sectors. However, the overall crude birth rate in the district (45.7 per 1000 population) remains higher than the crude death rate (28.1 per 1000 population), resulting in continued rapid population growth.
To examine risk factors for HIV-1 infection in three geographic strata (main road trading centers that service local and international traffic, small trading villages on secondary dirt roads that ...serve as foci for local communications, and agricultural villages off main and secondary roads) in Rakai District, Uganda.
Serological, sociodemographic, knowledge/behaviors and health survey conducted in 21 randomly selected community clusters; complete data were collected for 1292 consenting adults.
Fifteen per cent of the men and 24% of the women were HIV-1-positive. On univariate analysis, several sociodemographic and behavioral factors were significantly associated with risk of HIV infection, including age, place of residence, travel, occupation, marital status, number of sex partners, sex for money or gifts, history of sexually transmitted disease (STD), and history of injections. On multivariate analysis, age, residence and number of sex partners remained significantly associated with HIV infection in both sexes; a history of STD and not having been circumcised were significant in men. There was a significant interaction between place of residence and reported number of sex partners: for any given level of sexual activity, the risk of HIV infection was markedly increased if the background community prevalence was high.
Sexual transmission appears to be the primary behavioral risk factor for infection, but the risks associated with this factor vary substantially between the three geographic strata. These data can be used to design targeted interventions.
A significant number of chronic lymphocytic leukemia, follicular non-Hodgkin's lymphoma and Waldenström's macroglobulinemia patients, treated with fludarabine phosphate (fludarabine), are elderly ...with diminished renal function. Since the kidney eliminates approximately 60% of fludarabine's primary metabolite (F-ara-A), dose modification is necessary for all patients with impaired renal function including elderly patients.
In this study, 22 patients with varying levels of renal function received a single intravenous dose of fludarabine (25 mg m3), followed one week later by five (one per day) doses that were adjusted according to three predefined creatinine clearance (CLcr) levels. Relationships between renal function and F-ara-A clearance, F-ara-A exposure and F-ara-A -related toxicities were examined.
The results demonstrate that total F-ara-A clearance correlated with CLcr and that F-ara-A exposure levels and patient toxicity profiles were similar across treatment groups.
In conclusion, the CLcr-based fludarabine dose adjustments used in this study provided reasonably equivalent F-ara-A exposure with acceptable safety in patients with varying degrees of renal function.
Buchanan's model of fiscal equalization, widely discussed in Canadian literature and aimed at horizontal equity across the member jurisdictions of a federation, is reexamined. The first section ...traces its development. The second section raises some critical issues and examines the rationale of capacity equalization as an alternative approach. The third section examines Buchanan's conjecture that aggregate transfers under the two approaches tend to be similar. Their determinants are explored and the similarity hypothesis is sustained for simplifying assumptions. The fourth section further tests its validity for truncated samples of Canadian provinces and U.S. urban data.
Gold in the Stawell goldfield is hosted by a sequence of sulfide-mineralised metasediments, the Stawell Facies and Albion Formation, overlying chloritised basalts. Aeromagnetic anomalies in the ...northwestern part of the Stawell corridor display intense negative and positive lobes: at the Kewell prospect, these take the form of an axial high flanked by paired lows. Such a pattern requires that remanence dominates magnetisation, and that the net magnetisation must vary in direction across strike. Remanence demagnetisation analysis confirms the dominance of remanence over induction in the pyrrhotite-dominated basalt, Stawell Facies and Albion Formation sequence, and indicates the presence of both normal and reversed remanence, with directions strongly controlled by the dominant S
2
foliation. A minor proportion of the Stawell Facies and basalts that display coarse-grained, secondary magnetite are dominated by magnetic induction. Oriented samples from the Kewell prospect were overprinted during core recovery, precluding direct measurement of the directions of remanence. Hysteresis analysis, a well-established rock-magnetic technique that previously has had very little application to aeromagnetic interpretation, provides a model to understanding remanence at Kewell. Samples from throughout the Stawell corridor group in two populations, which define two parallel curves on a Day plot of hysteresis parameters. Each curve follows the form expected for mixtures of single- and multi-domain ferrimagnets, and the offset between the two curves resembles that reported in other research to arise from variations in the Fe:S ratio in pyrrhotite. Population A comprises samples from the Stawell Facies, and population B is dominantly drawn from the pyrrhotite-bearing basalts. We speculate that the distinction between the two populations reflects differences in the pyrrhotite arising from contrast between high fluid flow in the high-permeability Stawell Facies and lower fluid flow in the basalts. Fluid-flow modelling at Kewell has emphasised the influence of high fluid flow on the flanks of the basalt structure on the location of gold mineralisation: these high fluid flow regions underlie the negative lobes of the aeromagnetic anomaly and are characterised by samples that fall in hysteresis population A. Population B samples, by contrast, are distributed in the lower flow regime near the crest of the structure. Magnetic modelling that assigns a reversed remanence in population A material to the flanks of the structure closely matches the observed aeromagnetic profile. From this, we infer that the fluid-flow regime has a direct control on remanence polarity at Kewell, either by resetting remanence at the time of mineralisation or by changing the response of the high fluid flow regions to later remagnetisation processes.
CD2–CD48 interactions enhance T cell receptor-driven mouse T lymphocyte activation. However, the mechanism is not well understood. Here we show that blockade of CD2–CD48 interactions with anti-CD48 ...monoclonal antibody (mAb) inhibited interleukin (IL)-2 and interferon (IFN)-γ expression, as well as T cell proliferation in response to mitogenic anti-CD3 mAb, although more potent inhibition resulted from blocking CD28–CD80/CD86 interactions. Blockade of both CD2 and CD28 costimulation abrogated T cell proliferation and cytokine synthesis. Conversely, T cells stimulated with immobilized anti-CD3 and anti-CD2 mAb exhibited increased proliferation and IL-2 and IFN-γ expression, although a stronger enhancing effect was obtained with immobilized anti-CD3 and anti-CD28 mAb. Concurrent CD2 and CD28 costimulation caused a further increase in proliferation and cytokine synthesis. Stimulation of purified T cells with microsphere-immobilized anti-CD3 and anti-CD2 mAb increased IL-2 and IFN-γ mRNA stability. However, CD28 costimulation had a stronger enhancing effect on IL-2 and IFN-γ mRNA stability that was not further increased by concomitant CD2 signaling. CD2, therefore, costimulates T cell activation by stabilizing cytokine mRNA transcripts, albeit with less efficiency than CD28.
The phenolic content of condensed tannins varies considerably, depending on the method of determination. Even though the Stiasny precipitation number has been commonly used to estimate the amount of ...reactive tannin towards formaldehyde, particularly in adhesive applications, this estimation alone is not sufficient. In this study two methods of determining the amount of reactive tannin towards formaldehyde were examined. These were (1) the reactivity towards formaldehyde or the Stiasny precipitation number, and (2) the formaldehyde uptake. Five different types of tannin were examined from Rhizophora mucronata, P. radiata, mimosa, quebracho and chestnut. The study indicates that the phenolic content in tannin can be better estimated by determining both the Stiasny number and the amount of formaldehyde uptake. High correlation (r2 = 0.905) was detected between the two methods. The study also revealed that hot water extracts of R. mucronata contain relatively small amounts of reactive polyphenols and are less reactive than sulfite extracts. The consumption of formaldehyde by this type of tannin was only 0.294 molecules per flavanoid unit. Similar to R. mucronata, the sulfite extracts of P. radiata contain relatively high amounts of reactive polyphenols and reacted with substantially higher amounts of formaldehyde per flavanoid unit, comparable to mimosa and quebracho tannins. Nonetheless, the reactivity towards formaldehyde (gel time) of the latter tannins is muchlower, despite their higher polyphenolic content. Of the two methods used to estimate the polyphenolic content of bark extracts, the Stiasny number had a relatively higher correlation (r2 = 0.518) with gel time than formaldehyde uptake (r2 = 0.345) did. The behaviour of these tannins in relation to their reactivity and chemical structures is discussed.
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