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Copyright of West Indian Medical Journal is the property of West Indian Medical Journal (WIMJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses the community-based approaches' impact on pharmacies in expanding their public health role specially in the prevention of HIV in New York City. It mentions that there were thirteen pharmacies participated in New York's Expanded Syringe Access Program that permits nonprescription syringe sales to reduce incidence of syringe-sharing among injection drug users (IDUs). The pharmacies were enrolled in an intervention, linking IDU syringe costumers to medical/social services. The result of the research among the intervention pharmacies notes that community-based participatory aided in implementing a pilot structural intervention for promoting drug use understanding and HIV prevention among pharmacy-related services.

Computational fluid dynamic modelling was carried out on a series of pipe bends having R/r values of 1.3, 5, and 20, with the purpose of determining the accuracy of numerical models in predicting pressure loss data from which to informone-dimensional loss models. Four separate turbulence models were studied: the standard k-ϵ model, realizable k-ϵ model, k-ω model, and a Reynolds stress model (RSM). The results are presented for each bend in the form of upstream and downstream pressure profiles, pressure distributions along the inner and outer walls, detailed pressure and velocity fields as well as overall loss values. In each case, measured data were presented to evaluate the predictive ability of each model. The RSM was found to perform the best, producing accurate pressure loss data for bends with R/r values of 5 and 20. For the tightest bend with an R/r value of 1.3, however, predictions were significantly worse due to the presence of flow separation, stronger pressure gradients, and high streamline curvature. [ABSTRACT FROM AUTHOR]

Tag1 is an autonomous transposable element of Arabidopsis thaliana that displays tight developmental control of its excision during shoot development. To determine how Tag1 behaves in a monocotyledonous species, Tag1 was inserted in a 35S-GUS marker gene and the construct was introduced into rice. Tag1 showed somatic excision activity in four out of eleven transgenic lines examined. In leaves, excision was primarily restricted to vascular bundles and produced sectors composed of only a few cells. Excision events in flowers occurred predominantly in or near the major veins of the palea and lemma to produce small sectors. In roots, small sectors were evident, but they were few in number. These data show that the timing of Tag1 excision during rice shoot development is late and mimics the late excision behavior of Tag1 in Arabidopsis. One of the transgenic rice lines, which had a high frequency of somatic excision, produced several germinal revertants, one of which was characterized by a new Tag1 insertion band. The pattern of Tag1 transcripts and the footprint sequences left behind after excision in rice were found to be very similar to those in Arabidopsis. These results show that key properties of Tag1 transposition and behavior are conserved between monocots and dicots and that Tag1 has the potential to serve as an insertional mutagen in rice. [ABSTRACT FROM AUTHOR]

The RICE proficiency testing scheme for asbestos fibre counting operated until 1992 with industrial samples and with reference counts produced by an image analyser (Magiscan). The visual counts produced in RICE by the participating laboratories have now been used to develop a reliable reference count for these industrial samples. Concurrently with the routine participation in RICE. laboratones also counted samples from asbestos clearance operations, these counts were used to develop suitable reference counts and performance limits for this type of sample. The width of this satisfactory performance interval is proportional to the natural variation in the data on the samples and is therefore a fixed interval on the log scale (of sample density) for high density samples and a fixed interval on the square-root scale for low density samples (where counting normally stops after a fixed number of fields). These developments led to the introduction of visual reference counts and clearance samples into RICE during 1992. [ABSTRACT FROM PUBLISHER]

The Regular Interlaboratory Counting Exchanges (RICE) and the Asbestos Fibre Regular Informal Counting Arrangement (AFRICA) were initiated as U.K. and international schemes, respectively, to improve standards of counting asbestos fibres using phase contrast optical microscopy. In both schemes, reference samples are evaluated by participating laboratories in rounds of sample exchanges, and counting performance is assessed by comparing laboratory counts with reference counts. Their development is summarized from inception to the present day. This summary includes descriptions of the scope and scale of membership, the nature of reference samples and reference counts, and their main operational features. Criteria for classifying laboratory performance as satisfactory or unsatisfactory, based on performance ratings of counts in a single round and categories of counts over four consecutive rounds, are described. In the first round of RICE, systematic differences up to 150-fold occurred between mean laboratory counts, with 300-fold differences being observed for single samples; 77 laboratories were rated 1 (the best performers; i.e. those laboratories providing counts closest to the reference values), 48 laboratories were rated 2, and 50 laboratories were rated 3 (the worst performers; i.e. those laboratories providing counts furthest from the reference values). Performance improved appreciably in the next round; of the 175 original participants, the numbers of laboratories rated 1, 2 and 3 were 125, 44 and 6, respectively. Further improvements were achieved and maintained in subsequent rounds. Similar patterns of both short- and long-term improvement also occurred in AFRICA. Progress in developing both schemes further is described, particularly in relation to the nature of the reference samples and reference counts. [ABSTRACT FROM PUBLISHER]

The results of airborne dust measurements undertaken in the European MMMF manufacturing industry in conjunction with a retrospective epidemiology study were reported at a WHO conference in 1982. Subsequently, a reference scheme was instigated to develop reference evaluation procedures for use in epidemiology and to harmonise interlaboratory differences using these methods. These developments have resulted in an increase in the reported fibre concentrations for the above study by approximately three times. Estimates of the average airborne respirable fibre concentrations for combined occupational groups in glasswool manufacture ranged from <0.01 fibres/ml to 0.10 fibres/ml and from 0.02 fibres/ml to 0.14 fibres/ml in the rockwool plants.Information about the technical history of the factories has been obtained and the validity of using current fibre concentrations to estimate workers' past exposure is discussed. Three changes in production have been identified as having a potentially important effect on fibre levels: nominal fibre size, addition of oil to MMMF and labour intensive batch production techniques. It has been estimated that changes in these parameters may have reduced fibre levels by up to ten times. Based on the plant technical histories the production at each factory has been divided into three phases for use in the epidemiological analysis described in another paper at this symposium. [ABSTRACT FROM PUBLISHER]

In the mid-1970s, a meeting held at WHO in Copenhagen launched a research programme on the health effects of man-made mineral fibres. As part of this programme, a WHO/EURO Reference Scheme was initiated in 1980 to improve comparability of data obtained from epidemiological studies and thus reduce the level of uncertainty in the risk assessment process. The scheme involved developing reference methods for evaluating airborne MMMF concentrations and size distributions by phase contrast optical microscopy (PCOM) and scanning electron microscopy (SEM). These methods were tested in a series of inter-laboratory counting trials. Interim progress in the scheme was published in 1985. This paper updates the work of the scheme and confirms that the previously published improvements in reproducibility of measurement have been maintained. [ABSTRACT FROM PUBLISHER]

The European Reference Method (ERM) specified in the CEC Directive on Asbestos requires fibre counting to cease after 100 fibres have been counted or 100 fields of view have been evaluated, whichever is reached first, with a minimum of 20 fields being examined. With this stopping rule, more of the filter area is evaluated at lower concentrations than is examined when the concentration is around the compliance limit. This paper describes an investigation carried out to identify and test alternatives to the ERM stopping rule which would reduce the counting effort at low concentrations whilst retaining an acceptable degree of accuracy. Simulation studies were performed on available data, involving random selections of fibres and fields. This, together with theoretical considerations, led to the definition of two candidate stopping rules applicable to assessing compliance with the European control limit for chrysotile and amosite of 1.0 fibre ml. These candidate rules are: (a) count until at least 135 fibres have been counted or until 30 fields have been examined; a minimum of 20 fields must be examined; (b) examine 20 fields; if fewer than 75 fibres, or more than or equal to 105 fibres have been counted, then stop counting. Otherwise, continue counting until at least 180 fibres have been counted or until 40 fields have been examined. The two selected candidate rules were compared with the ERM rule in a small experimental trial. Evaluated fibre densities obtained by the candidate and ERM rules did not differ systematically. For concentrations below about 0.8 fibres ml, the time involved in applying the candidate rules progressively decreased as concentration decreased; at low concentrations, application of the candidate rules took as little as one-fifth of the time of the ERM rule. [ABSTRACT FROM PUBLISHER]

The United Kingdom Central Reference Scheme for asbestos counting has been expanded by initiating a series of regular interlaboratory counting exchanges (RICE) to minimize national within- and between-laboratory differences in asbestos fibre counts obtained by the membrane filter method. The scope of the present RICE operation is described and results are presented depicting current interlaboratory differences. National scatter is unacceptably large; up to ten-fold systematic differences occur between visual-counting laboratories, whilst random differences in counts of up to 100-fold occur on the same sample. For the reference samples evaluated, counts made by Magiscan automated image analysers are generally near the national mean and differences between Magiscans are usually small compared with differences between visual-counting laboratories. Results obtained by an experienced group of laboratories relative to Magiscan have been used to derive a categorization procedure for assessing laboratory performance. Some details are given concerning future operation of RICE with a view to improving national reproducibility. A European-based scheme similar to RICE is needed to help ensure that the community asbestos directive applies uniformly in CEC countries. [ABSTRACT FROM PUBLISHER]

Shift-average radon and thoron daughter working levels have been measured at 11 collieries in the U.K. Levels were low (generally less than 20 milli-working levels) compared with those typical of uranium mines. The possible influences of various factors on the level of activity were examined, but a correlation was found only with ventilation distances from pit bottom to the sampling site. [ABSTRACT FROM PUBLISHER]

Routine dust and radiological statistics have been examined for 274 British collieries for the period 1970–1975. These data were used to identify collieries where progression of simple pneumoconiosis appeared unusually high or low in relation to the dust levels. Eight of these collieries were selected for further study. For each selected colliery, an assessment was made of pre-1970 dust conditions, the pattern of dust distribution in the coalface area and the time spent by faceworkers at other collieries. Composition, size and toxicity characteristics of the dusts were also measured, as were oxides of nitrogen levels. The apparently anomalous results at five collieries are at least partly explicable in terms of environmental and manpower movement considerations. Similar information, however, does not explain the marked increase in progression of simple pneumoconiosis observed in 1972 at the other collieries. It is possible that in these cases the apparent discrepancies may be associated with temporal variations in the radiological technique. [ABSTRACT FROM PUBLISHER]

Tag1 is an autonomous transposable element (3.3 kb in length) first identified as an insertion in the CHL1 ( NRT1) gene of Arabidopsis thaliana. Tag1 has been found in the Landsberg erecta ecotype of A. thaliana but not in Columbia or WS. In this paper, 41 additional ecotypes were examined for the presence of Tag1. Using an internal Tag1 fragment as probe, we found that DNA from 19 of the 41 ecotypes strongly hybridized to Tag1. Almost all of the Tag1-containing ecotypes had only one or two copies of Tag1 per haploid genome, as determined by Southern blot analysis. The only exception, Bf-1 from Bretagny-sur-Orge, France, had four copies. Two ecotypes, Di-G and S96, gave identical Southern blot patterns to that of Landsberg erecta and were subsequently shown to contain Tag1 at the same two positions found in Landsberg erecta (loci designated as Tag1-2 and Tag1-3). Two other ecotypes, Ag-0 and Lo-1, had a Tag1 element located at Tag1-2 but not at Tag1-3. The distance between these two loci was determined to be 0.37 cM. Analysis of DNA from two related species, A. griffithiana and A. pumila, showed that both species contain sequences that hybridize to Tag1 and that could be amplified with an oligonucleotide specific to the terminal inverted repeats of Tag1. These results show that Tag1 and related elements are present, and may be useful for insertional mutagenesis, in many A. thaliana ecotypes and several Arabidopsis species. [ABSTRACT FROM AUTHOR]