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PubMed2006

Using geographic information systems to identify prospective marketing areas for a special library.

BACKGROUND: The Center for Disability Resources (CDR) Library is the largest collection of its kind in the Southeastern United States, consisting of over 5,200 books, videos/DVDs, brochures, and audiotapes covering a variety of disability-related topics, from autism to transition resources. The purpose of the library is to support the information needs of families, faculty, students, staff, and other professionals in South Carolina working with individuals with disabilities. The CDR Library is funded on a yearly basis; therefore, maintaining high usage is crucial. A variety of promotional efforts have been used to attract new patrons to the library. Anyone in South Carolina can check out materials from the library, and most of the patrons use the library remotely by requesting materials, which are then mailed to them. The goal of this project was to identify areas of low geographic usage as a means of identifying locations for future library marketing efforts. METHODS: Nearly four years worth of library statistics were compiled in a spreadsheet that provided information per county on the number of checkouts, the number of renewals, and the population. Five maps were created using ArcView GIS software to create visual representations of patron checkout and renewal behavior per county. RESULTS: Out of the 46 counties in South Carolina, eight counties never checked out materials from the library. As expected urban areas and counties near the library's physical location have high usage totals. CONCLUSION: The visual representation of the data made identification of low usage regions easier than using a standalone database with no visual-spatial component. The low usage counties will be the focus of future Center for Disability Resources Library marketing efforts. Due to the impressive visual-spatial representations created with Geographic Information Systems, which more efficiently communicate information than stand-alone database information can, librarians may benefit from the software's use as a supplemental tool for tracking library usage and planning promotional efforts.

Journal Article↗
PubMed2000

The London School of Hygiene and Tropical Medicine: a new century of malaria research.

The global malaria situation has scarcely improved in the last 100 years, despite major advances in our knowledge of the basic biology, epidemiology and clinical basis of the disease. Effective malaria control, leading to a significant decrease in the morbidity and mortality attributable to malaria, will require a multidisciplinary approach. New tools--drugs, vaccine and insecticides--are needed but there is also much to be gained by better use of existing tools: using drugs in combination in order to slow the development of drug resistance; targeting resources to areas of greatest need; using geographic information systems to map the populations at risk and more sophisticated marketing techniques to distribute bed nets and insecticides. Sustainable malaria control may require the deployment of a highly effective vaccine, but there is much that can be done in the meantime to reduce the burden of disease.

Animals↗
PubMed2006

Rural surgical services in two Canadian provinces.

OBJECTIVE: Contrast alternative health delivery systems and the use of differently trained physician providers in the supply of surgical services to rural residents in 2 Canadian provinces. METHODS: Four surgical procedures (carpal tunnel release, inguinal herniorrhaphy, appendectomy and cholecystectomy) provided to rural residents of Alberta and Northern Ontario were identified between 1997/98 and 2001/02. Surgical staff were identified as specialists or non-specialists. Rural populations were mapped into the catchment areas of rural acute care facilities. Rural surgical programs were characterized by the level of surgical service available locally. RESULTS: Alberta and Northern Ontario have a similar number of rural surgical programs staffed by Canadian-certified general surgeons (10 and 12, respectively). However, Alberta has 27 smaller rural surgical programs staffed by non-specialist surgeons and Northern Ontario has only 4. These non-specialist surgeons play a significant role in Alberta, often in collaboration with specialist surgeons. In Northern Ontario the non-specialist surgeons play a minor role. The small rural surgical programs in Northern Ontario that are staffed by specialist surgeons are significantly more successful in retaining the local surgical caseload compared with similar programs in Alberta. CONCLUSIONS: The principal differences between Alberta and Northern Ontario in the delivery of rural surgical services are the greater number of small rural surgical programs in Alberta, and the substantial role of non-specialist surgical staff in these programs.

Alberta↗
PubMedDate not supplied

[Scales for the analysis of health care provision].

Geographic analysis of the provision of health care has various levels. The inter-country level is suitable for observing flows of health personnel crossing national borders. At the national level, a variety of health facilities management policies may be observed in different regions. The regional level may be used for evaluating access to services, in particular those between rural and urban areas, or even between cities of the same size. Disparities of access to services may be accompanied by gaps between the provision of and the need for services. At a lower level, France has the level of "canton." Nevertheless, this is not always relevant, especially for observing secondary and tertiary care. Data gathered at the "municipalité" level are more precise, in that they allow analysts to follow the circulation of patients. However, this is expensive, and does not go beyond the resource assessment stage. On the basis of fieldwork, one can subdivide the territory into units characterized by specific relations, e.g., those of care providers and the corresponding population. Such mapping crosses conventional administrative limits and emphasizes different social groups and their organization.

Delivery of Health Care↗
PubMed1988

ApoB gene MspI RFLP in exon 26 changes amino acid 3611 from Arg to Gln.

An apolipoprotein B gene MspI RFLP was identified by the use of a probe to a portion of the 3' end of the gene. By Southern blotting analysis after digestion with MspI, this probe detected either a 9 kb or a 2.6 kb fragment. Family studies showed that these corresponded to alleles that segregated in a simple Mendelian fashion. The minor allele (9.0 kb) had a frequency of approximately 12% in an unrelated Caucasian population. Restriction mapping showed that the minor allele was due to the loss of an MspI site in exon 26. Sequencing of both alleles in the region containing the polymorphic MspI site revealed a single-base pair alteration which abolished the MspI site at codon 3611 of the mature apoB protein. In the major allele, this codon is CGG, which specifies Arg; whereas in the minor allele, it was CAG, which codes for Gln.

Apolipoproteins B↗
PubMed1979

Regulation of Leishmania populations within the host. III. Mapping of the locus controlling susceptibility to visceral leishmaniasis in the mouse.

Acute susceptibility of the mouse to Leishmania donovani is largely determined by a single locus designated Lsh. Linkage between the Lsh locus and the Chromosome 1 marker Id-1 was detected using several sets of recombinant inbred strains. Chromosome 1 linkage was confirmed in backcross generations using isoenzymes and a cytogenetic marker. The data indicate that the gene order is centromere-Lsh-Id-1-ln-Dip-1. The estimated recombination frequency between Lsh and Id-1 is 0.12 +/- 0.04. This mapping is away from the known histocompatibility loci.

Alleles↗
PubMed1985

Distribution of serotonin-immunoreactive cell bodies and processes in the abdominal ganglion of mature Aplysia.

Sensitization of the gill withdrawal reflex in Aplysia californica is an elementary form of learning, in part resulting from presynaptic facilitation of the LE mechanoreceptor neurons of the abdominal ganglion. It has previously been established that either application of serotonin or direct stimulation of a group of facilitatory neurons, the L29 cells of the abdominal ganglion, can simulate the effect of physiological stimulation in producing presynaptic facilitation. Because the evidence that serotonin serves as a facilitatory transmitter was indirect, we examined the distribution of serotonin-immunoreactive fibers and cell bodies in the abdominal ganglion in order to answer two questions: (1) do the sensory neurons receive serotonergic innervation and (2) are the L29 cells serotonergic? We observed two distinctive patterns of serotonergic innervation within the ganglion, sparse and dense. The sparse pattern is correlated with a serotonin-stimulated increase in cAMP in identified target cells, while the dense innervation is not. We found a sparse distribution of serotonin-immunoreactive fibers with varicosities close to both cell bodies and processes of identified LE sensory cells. It therefore is likely that the sensory neurons do receive serotonergic innervation. We also mapped the population of serotonergic neuronal cell bodies in the ganglion, and found five clusters of neurons. Cells in one of these clusters, the identified RB neurons, had previously been shown to synthesize serotonin from tryptophan and to contain the neurotransmitter in high concentration. Identified L29 facilitator cells marked by injection with Lucifer Yellow do not contain serotonin immunoreactivity and therefore evidently are not a source of serotonergic input onto sensory cells.

Animals↗
PubMed1994

Spatiotemporal structure of somatosensory responses of many-neuron ensembles in the rat ventral posterior medial nucleus of the thalamus.

Classically, the rat ventral posterior medial (VPM) nucleus of the thalamus has been considered as a simple passive relay for single-whisker information to the primary somatosensory cortex (SI). However, recent reports have suggested that the VPM could contain a much more coarsely coded and spatiotemporally complex representation of the rat whisker pad. To address this possibility properly, we have carried out chronic simultaneous recordings of large numbers (up to 23) of single neurons, distributed across the entire VPM, in both awake and lightly anesthetized adult rats. Quantitative, computer-based reconstruction of receptive fields (RFs) revealed that single VPM neurons exhibit significant responses to discrete stimulation of as many as 20 single whiskers (mean +/- SD RF size, 13.7 +/- 4.8 whiskers). By defining multiple response magnitude (RM) thresholds it was possible to subdivide these large VPM RFs quantitatively into a prominent center (mean +/- SD, 1.41 +/- 0.70 whiskers, RM > 95%) and an excitatory surround (up to 18 whiskers, RM < 95%). VPM neurons exhibited both short-latency responses (SLRs, from 4 to 10 msec poststimulus) and/or long-latency responses (LLRs, 15-25 msec), each followed by inhibitory responses. Though LLRs were weaker (mean +/- SD, 47.19 +/- 33.34 Hz) than SLRs (119.63 +/- 50.12 Hz), they often defined RFs that differed considerably from those defined by the SLRs of the same cell. In particular, VPM cells with short-latency RFs centered in caudal whiskers (e.g., C1, D1, E1) showed a poststimulus time-dependent shift of these RF centers toward the rostral whiskers (e.g., C4, D4, E4). These caudal-to-rostral (C-->RF shifts occurred in neurons with the largest RFs of our sample (17.2 +/- 2.4 whiskers). On the other hand, VPM cells with short-latency RFs centered in rostral whiskers had the smallest RFs (13.1 +/- 4.1 whiskers) and usually did not exhibit time-dependent RF center shifts. Multivariate analysis revealed that these two groups of VPM neurons, C-->R shifting and rostral position (RP) cells, could be statistically distinguished according to a combination of three RF attributes (short-latency RF center location, RF size, and magnitude of RF center shift). Quantitative, computer-based reconstruction of "population response maps" demonstrated that the "place" coding for each single whisker in the VPM involved a distinct weighted contribution from a large proportion of the simultaneously recorded neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

Anesthesia↗
PubMed1995

Obtaining genetic markers by using double-stringency PCR with microsatellites and arbitrary primers.

A technique to obtain genetic markers is described. PCR is performed at two different annealing temperatures in a single reaction mixture. During the first cycles, a single microsatellite oligonucleotide is used as primer to amplify DNA between two microsatellite regions. The annealing temperature and consequent stringency is then lowered, and in further cycles a random-amplified polymorphic DNA (RAPD) primer exponentially amplifies parts of the previously amplified fragments, which contain sequences complementary to the RAPD primer. The first round of specific amplification is found to be crucial for obtaining consistent, repeatable results, as compared with the results obtained by RAPD alone. This technique was proven to produce genetically informative markers, as revealed by crosses performed with Drosophila mercatorum strains, and it can be used for genetic mapping or population genetics studies.

Animals↗
PubMed1997

Flow cytometric analysis of glucose transport by rat brain cells.

The fluorescent, non-metabolizable glucose analog 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-6-deoxyglucose (NBDG) was used to measure rates of hexose transport by dissociated brain cells from developing and adult rats. Flow cytometric analysis of glucose uptake and expression of glucose transporters was performed by mapping on size by granularity, which discriminated between neurons and astrocytes in a suspension of mixed brain cells. These mapped cell populations were identified by immunofluorescent staining with antisera to neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP). Specific uptake of the analog by membrane glucose transporters was confirmed by its inhibition by D-glucose and by cytochalasin B. Both neurons and astrocytes expressed the GLUT1 and GLUT3 transporter isoforms. This was confirmed by the additive inhibition of NBDG uptake by antibodies to these transporter isoforms in both cell types. The advantages of flow cytometric analysis of glucose transport include continuous monitoring over extremely short periods of time, increased precision of cell-by-cell flow cytometric measurements versus average uptake rates obtained with radioisotopes, and simultaneous analysis of uptake by different cell populations. Moreover, both uptake rates and the abundance of specific transporters can be determined directly and rapidly on the same cell suspension.

4-Chloro-7-nitrobenzofurazan↗
PubMed1999

Multipoint genetic mapping of quantitative trait loci with dominant markers in outbred populations.

We present a multipoint algorithm for mapping quantitative trait loci (QTLs) using dominant markers. The algorithm is designed for outbred populations and is particularly suited for large families. The algorithm works with either codominant or dominant markers, either of which may be interspersed within the same linkage map. Concurrently, the algorithm also partitions dominance variance at the QTL. Computer simulations show that with large families, QTL mapping with dominant markers can be almost as powerful as with bi-allelic, codominant markers. Yet despite this, other situations show a large standard deviation in the estimate of the QTL position, thus making QTL mapping with dominant markers in outbred populations a useful detection tool, albeit limited in its resolution.

Algorithms↗
PubMed1991

Genetic similarity maps and immunoglobulin allotypes of eleven populations from the Pyrenees (France).

The genetic heterogeneity of eleven populations from the Pyrenees (France) based on the polymorphism of the immunoglobulin allotypes is studied by means of a 'genetic similarity map'. The method described here, called 'Mobile Node Method', allows the deformation of a square grid, in which the studied region is represented, by moving the nodes at each step in order to reduce the difference between the geographic and genetic distances. This tool allows the overall quantification of the genetic heterogeneity of a population set and possibly the study of its dynamics. Other maps constructed to complete the interpretation are 'map of moving vectors', 'iso-displacement curves' and 'site displacements'. This study identified an overall genetic homogeneity among the Pyrenean populations and several local genetic heterogeneities in different regions.

France↗
PubMed2004

Comparative high-resolution analysis of linkage disequilibrium and tag single nucleotide polymorphisms between populations in the vitamin D receptor gene.

A genome-wide map of single nucleotide polymorphisms (SNP) and a pattern of linkage disequilibrium (LD) between their alleles are being established in three main ethnic groups. An important question is the applicability of such maps to different populations within a main ethnic group. Therefore, we have developed high-resolution SNP, haplotype and LD maps of vitamin D receptor gene region in large samples from five populations. Comparative analysis reveals that the LD patterns are identical in all four European populations tested with two small regions of 1.3 and 5.7 kb at which LD is disrupted completely resulting in three block-like regions over which there is significant and extensive LD. In an African population the pattern is similar, but two additional LD-breaking spots are also apparent. This LD pattern suggests combined action of recombination hotspots and founder effects, but cannot be explained by random recombination and genetic drift alone. Direct comparison indicates that the tag SNPs selected in one European population effectively predict the non-tag SNPs in the other Europeans, but not in the Gambians, for this region.

Chromosomes, Human, Pair 12↗
PubMed2003

On the determination of recombination rates in intermated recombinant inbred populations.

The recurrent intermating of F(2) individuals for some number of generations followed by several generations of inbreeding produces an intermated recombinant inbred (IRI) population. Such populations are currently being developed in the plant-breeding community because linkage associations present in an F(2) population are broken down and a population of fixed inbred lines is also created. The increased levels of recombination enable higher-resolution mapping in IRI populations relative to F(2) populations. Herein we derive relationships, under several limiting assumptions, for determining the expected recombination fraction in IRI populations from the crossover rate per meiosis. These relationships are applicable to situations where the inbreeding component of IRI population development is by either self-fertilization or full-sib mating. Additionally, we show that the derived equations can be solved for the crossover rate per meiosis if the recombination fraction is known for the IRI population. Thus, the observed recombination fraction in any IRI population can be expressed on an F(2) basis. The implications of this work on the expansion of genetic maps in IRI populations and limits for detecting linkage between markers are also considered.

Chromosome Mapping↗
PubMed1996

Population dynamics and global change: the need for new conceptual maps.

The author criticizes current approaches to the study of global population problems as typified by the discussions at the International Conference on Population and Development, held in Cairo, Egypt, in 1994. "Current approaches to population: (1) focus too much on humans and not on their interactions over time with populations of other species; (2) focus too much on the number of humans and not on their differential resource use and environmental impact; (3) accept uncritically the assumptions and concepts of industrial society regarding the nature of progress and the neutrality of technologies, markets, and trade. Broader and more integrated approaches are needed to address current international and global realities and trends." Some conceptual datasets that would illustrate a more effective approach to population problems are introduced.

Data Collection↗
PubMed2004

[Statistic-mapping modeling of rheumatic diseases prevalence among population of different regions of Russia].

AIM: To assess feasibility of the method of mapping modeling for spacial featuring of rheumatic diseases (RD) morbidity statistics for population of Russia. MATERIAL AND METHODS: Population morbidity statistics for 78 administrative units of the Russian Federation (1993-2000) were processed. Statistic-mapping modeling employed weighted mean interpolation i.e. mathematic prediction of the sign value depending on its magnitude in basic points. RESULTS: Mapped images of RD prevalence, prevalence/primary morbidity values and number of documented cases/number of rheumatologists demonstrate special distribution of the signs studied about the RF territory. The estimation of mean, minimal, maximal values and dispersion of each sign established dynamic trends in the markers for the period under study(increased area with RD prevalence above 95/1000 from 15.9 to 44.5%; increased mean ratio prevalence/morbidity from 2.8 to 3.2 and decreased ratio of patients/rheumatologists from 10882 to 9031). Regions with minimal and maximal values are shown. CONCLUSION: Statistic-mapping modeling demonstrates spacial distribution of the markers, reveals the relations between them.

Humans↗
PubMed1999

The human immunoglobulin variable lambda locus IGLV9 gene is a monomorphic marker in the urban Brazilian population.

The physical map of the human immunoglobulin variable lambda locus (IGLV) located on chromosome 22q11.1-q11.2 shows the existence of 52 functional V-lambda genes distributed among three V-clusters. The IGLV9S1 gene, located in the V-B cluster, is a sequence tagged site and is a useful marker for restriction fragment length polymorphism (RFLP) population studies. The V-lambda genes are associated in the genome with EcoRI fragments detectable in Southern blots of genomic DNA samples. We have analysed DNA samples of an urban Brazilian population by Southern-EcoRI-RFLP using an IGLV9 gene segment. Among 75 unrelated individuals analysed, we detected a single 6.0 kb EcoRI fragment containing the IGLV9 gene at 100% frequency. Reverse transcription followed by polymerase chain reaction (RT-PCR) of peripheral blood leukocyte total RNA from unrelated individuals showed that IGLV9S1 is a functional gene contributing to the B lymphocyte repertoire. These data represent evidence for monomorphism of the IGVL9S1 gene in this urban population. We demonstrate that IGLV9S1 is a functional single copy gene and is an important marker in the IGLV locus.

Biomarkers↗
PubMed2006

Power of QTL mapping experiments in commercial Atlantic salmon populations, exploiting linkage and linkage disequilibrium and effect of limited recombination in males.

Whereas detection and positioning of genes that affect quantitative traits (quantitative trait loci (QTL)) using linkage mapping uses only information from recombinants in the genotyped generations, linkage disequilibrium (LD) mapping uses historical recombinants. Thus, whereas linkage mapping requires large family sizes to detect and accurately position QTL, LD mapping is more dependent on the number of families sampled from the population. In commercial Atlantic salmon breeding programmes, only a small number of individuals per family are routinely phenotyped for traits such as disease resistance and meat colour. In this paper, we assess the power and accuracy of combined linkage disequilibrium linkage analysis (LDLA) to detect QTL in the commercial population using simulation. When 15 half-sib sire families (each sire mated to 30 dams, each dam with 10 progeny) were sampled from the population for genotyping, we were able to detect a QTL explaining 10% of the phenotypic variance in 85% of replicates and position this QTL within 3 cM of the true position in 70% of replicates. When recombination was absent in males, a feature of the salmon genome, power to detect QTL increased; however, the accuracy of positioning the QTL was decreased. By increasing the number of sire families sampled from the population to be genotyped to 30, we were able to increase both the proportion of QTL detected and correctly positioned (even with no recombination in males). QTL with much smaller effect could also be detected. The results suggest that even with the existing recording structure in commercial salmon breeding programmes, there is considerable power to detect and accurately position QTL using LDLA.

Animals↗