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PubMed1991

Geographic information systems: their application in animal disease control.

Geographic information systems (GIS) are computerised information systems that allow for the capture, storage, manipulation, analysis, display and reporting of geographically referenced data. They have been used in recent years for a wide variety of purposes, including town planning and environmental resource management. The technology has many features which make it ideal for use in animal disease control, including the ability to store information relating to demographic and causal factors and disease incidence on a geographical background, and a variety of spatial analysis functions. A number of possible veterinary applications are suggested, and three examples of the use of GIS in New Zealand are discussed.

Animal Diseases↗
PubMed2001

An ecological analysis of leukemia incidence around the highest 137Cs concentration in Poland.

Cancer has long been known to be a hazard of exposure to ionizing radiation. However, the assessment of health effects from exposure to radiation is a matter of considerable controversy. This paper presents results of a retrospective study of leukemia incidence (203-207, ICD-9) around the highest 137Cs pollution in Poland (as an effect of the Czarnobyl disaster and/or military bomb tests). The data relating to all the registered leukemias in males and females originated from the Regional Cancer Registry in Opole. The information on 137Cs concentration rates in Opole province was derived from the state monitoring provided by the Polish Geological Institute in Warsaw. The spatial analysis--based on the random-effects Poisson regression model--was carried out via the Markov Chain Monte Carlo (MCMC) technique (Gibbs sampling) using BUGS software. The model incorporated epidemiological data and an ecological covariate--isotope concentrations--and provided a framework for estimating the strength of a dose-response relationship. The differences in incidence levels were quantified by traditional standardized morbidity ratios (SMRs) and presented in thematic maps as well as in combined charts of distance-disease-dose relations. Additionally, to assess spatial disease clustering, a Tango test was adopted. The results of this ecological study suggest that the 137Cs concentrations did not have any negative influence on the exposed population.

Bayes Theorem↗
PubMed2004

Analysis on the dispersal pattern of newly introduced Latrodectus hasseltii (Araneae: Theridiadae) in Japan by spider diagram.

The dispersal pattern of the widow spider Latrodectus hasseltii (Araneae: Theridiadae), in Osaka Prefecture, Japan, was analyzed from accumulated survey data of spider distribution. All confirmed infested points from 1996 to 2002 were plotted on a map, and infested points in each survey year were connected with the nearest previously confirmed points. Expansion patterns of the confirmed habitats were analyzed by year and dispersion distances were classified by using spider diagram, one of method of geographical information system spatial analysis. L. hasseltii moves by walking step by step on the ground, mainly in coastal areas during early stages of infestation, and also can be conveyed over distances by various vehicles, mainly in inland areas. These analyses show L. hasseltii does not move by ballooning.

Animals↗
PubMed1983

An approach to the functional anatomy of the sacroiliac joints in vivo.

This first part of this paper is a review of the literature on the functional anatomy of the sacroiliac joint followed by a preliminary biomechanical study of the fresh post mortem pelvis. The latter was done in order to determine the coefficients of the screw matrix and the position of the instantaneous centers of rotation during the symmetrical movements of nutation and contranutation simulated in the biomechanics laboratory. The main part of this work deals with the spatial analysis in vivo of the relative displacements of the iliac bones with respect to the sacrum in the course of dissymmetrical movements of the pelvis. In the different phases of movement, the roentgenographic observation of the position of the bony components with respect to a three-dimensional orthonormal reference system required the use of material based on the principles of photogrammetry. This technique was used to achieve spatial reconstruction of the data recovered from a series of orthogonal x-ray films of the sacroiliac joints. Data retrieval was carried out on a digital table linked to a computer with a graphic terminal so that the information could be displayed in the form of rectangular coordinates of defined points on the bone. Owing to the limited amplitude of articular displacement, a statistical study was required to retrieve the coordinates from the projection of these points on the X-ray film with an estimated threshold of significance of 0.1 and an error of +/- 0.1 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Functional organization of auditory cortex in the mongolian gerbil (Meriones unguiculatus). II. Tonotopic 2-deoxyglucose.

The tonotopic organization of the auditory cortex in the Mongolian gerbil was mapped with 2-deoxyfluoro-D-glucose (2DG) using narrow-band frequency-modulated tones of different centre frequency (FM tones) and tones periodically alternating between two different frequencies (alternating tones) as stimuli. Continuous tone bursts of a constant frequency and repetition rate were used in initial experiments. Continuous tones produced 2DG patterns similar to those observed in animals that were not specifically stimulated. With tone bursts of constant frequency and repetition rate variable patterns were observed, some of which could be interpreted only in retrospect in the light of results obtained with FM tones and alternating tones. These stimuli, in contrast, produced differential metabolic responses which in conjunction with 2DG data from monaural animals and electrophysiological data made it possible to distinguish a primary auditory field AI with its dorsal region Ald, an anterior auditory field AAF, a ventral field V, a dorsoposterior field DP and a ventroposterior field VP, a dorsal field D, and in addition an anteroventral field AV. In the largest field (AI) and the smaller rostrally adjacent field AAF, frequency-specific dorsoventral bands of labelling (isofrequency contours) were mapped quantitatively. Bands shifted as a function of frequency relative to each other and to an independent spatial reference line in the lateral hippocampus. Spatial analysis of the single bands obtained with FM tones, and of the double bands obtained with alternating tones in both fields, revealed roughly mirror-imaged tonotopic maps of AI and AAF. In AI the progression from low to high frequencies was from caudal to rostral and in AAF the gradient was reversed, leading to a common high-frequency border of the two fields. In AI, the spatial resolution for frequencies below 16 kHz was in similar intervals per octave and higher for frequencies below 1 kHz. AI showed a somewhat higher spatial resolution for frequencies (at least below 1 kHz) as well as longer isofrequency contours than AAF. The 2-deoxyglucose patterns provided average tonotopic maps and topological data on various fields, as well as reliable landmarks in the gerbil's auditory cortex.

Acoustic Stimulation↗
PubMed2002

GIS prediction model of malaria transmission in Jiangsu province.

OBJECTIVES: To perform GIS spatial analysis on malaria transmission patterns in Jiangsu after setting up a malaria database and developing GIS model of malaria transmission in Jiangsu province. METHODS: The epidemiological GIS database of malaria in Jiangsu province was established using ArcView 3.0a software. The climate data covering Jiangsu province and its peripheral area were extracted from the FAOCLIM database, the total growing degree days (TGDD) for Plasmodium vivax were calculated, and spatial distribution for TGDD was analyzed by ArcVeiw 3.0a. RESULTS: The predicted malaria distribution map based on TGDD was created, which showed that the transmission of malaria decreased gradually from west to east, which can be divided into three belts according to the degree of transmission. The 14-year mean morbidity distribution map of malaria in Jiangsu showed that the middle and west parts of Jiangsu is the most serious endemic area. The morbidity in the areas along the Taihu valley, such as Suzhou, Wuxi and Changzhou, as well as Nantong and a few of northern counties are the lowest. The morbidity of other places is at the middle level. The 14-year mean morbidity distribution map of malaria is correlated with predicted malaria distribution map for TGDD. CONCLUSION: It is possible to monitor the malaria transmission by GIS predicted model based on TGDD.

China↗
PubMed2001

A geographic analysis of motor vehicle collisions with child pedestrians in Long Beach, California: comparing intersection and midblock incident locations.

OBJECTIVES: The purpose of this study was to use geographic information system (GIS) software to locate areas of high risk for child pedestrian-motor vehicle collisions in the city of Long Beach and to compare risk factors between midblock and intersection collisions. METHODS: Children 0-14 years of age involved in a motor vehicle versus pedestrian collision that occurred on public roadways in Long Beach, CA, between 1 January 1992 and 30 June 1995, were identified retrospectively from police reports. The GIS software program, ArcView, was used for spatial analysis and distance calculations. chi2 Tests were used to compare the distribution of the characteristics between intersection and midblock collisions. RESULTS: The average annual incident and fatality rate was 183.3/100,000 children/ year and 2.4/100,000 children/year, respectively. Children less than 5 years of age were significantly more likely to be hit at a midblock location while those aged 5-9 and 10-14 were more often hit at an intersection. Intersection collisions were more likely to occur on major arterials and local streets, and the driver to be the primary party at fault (p<0.001). While intersection incidents tended to occur further from the child's home (64.4%) the majority of midblock incidents (61.5%) occurred within 0.1 miles of the child's residence. For both midblock and intersection locations, pedestrian collisions tended to occur more frequently in those census tracts with a larger number of families per census tract-a measure of household crowding and density. CONCLUSIONS: Future studies taking into consideration traffic volume and vehicle speed would be useful to focus prevention efforts such as environmental modifications, improving police enforcement, and educational efforts targeted at parents of younger children. As GIS illustrative spatial relationships continue to improve, relationships between pedestrian collision sites and other city landmarks can advance the study of pedestrian incidents.

Accidents, Traffic↗
PubMed1986

Geographical patterns of cancer mortality in China.

This research note discusses the China cancer mortality data and the methodological problems involved in spatial analysis of these data. Some of the research findings produced by mapping and analyses of the cancer data at the provincial level are also summarized. The two most common cancers in China, stomach and esophagus, were found to have no significant correlation with some selected physical variables and population density, suggesting the need to examine other socio-economic variables such as dietary habit. The study also suggests that the type of diet which may be responsible for these two cancers could be very different from each others. Colon and rectum, leukemia, and breast cancers were found to have very high positive spatial autocorrelation and high correlation with population density--a result contrary to previous findings in the West. Future research using a geographic information system approach and county data is suggested.

Adult↗
PubMed2005

Lead exposure and (n-3) fatty acid deficiency during rat neonatal development affect subsequent spatial task performance and olfactory discrimination.

Docosahexaenoic acid [22:6(n-3), DHA] is important for optimal infant central nervous system development, and lead (Pb) exposure during development can produce neurological deficits. Long-Evans strain rats were fed either an (n-3) deficient [(n-3) Def] diet to produce brain DHA deficiency, or an adequate [(n-3) Adq] diet through 2 generations. At the birth of the 2nd generation, the dams were subdivided into 4 groups and supplied drinking water containing either 5.27 mmol/L (Pb) or sodium (Na) acetate until weaning. Rats were killed at 3 wk (weaning) and 11 wk (maturity) for brain Pb and fatty acid analysis. Spatial task and olfactory-cued behavioral assessments were initiated at 9 wk. Rats in the (n-3) Def group had a 79% lower concentration of brain DHA compared with the (n-3) Adq group with no effect of Pb exposure. At weaning, Pb concentrations were 7.17 +/- 0.47 nmol Pb/g of brain (wet weight) in the (n-3) Adq-Pb group and 6.49 +/- 0.63 nmol Pb/g of brain (wet weight) in the (n-3) Def-Pb group. At maturity, the brains contained 1.30 +/- 0.22 and 1.07 +/- 0.12 nmol Pb/g (wet weight), respectively. In behavioral testing, significant effects of both Pb and DHA deficiency were observed in the Morris water maze probe trial and in 2-odor olfactory discrimination acquisition and olfactory-based reversal learning tasks. Both lactational Pb exposure and (n-3) fatty acid deficiency led to behavioral deficits with additive effects observed only in the acquisition of 2-odor discriminations.

Aging↗
PubMed2004

Observed winter warming of the Chesapeake Bay estuary (1949-2002): implications for ecosystem management.

A large number of studies have documented 20th century climate variability and change at the global, hemispheric, and regional levels. However, understanding the implications of climate change for environmental management necessitates information at the level of the ecosystem. Historical monitoring data from the Chesapeake Bay estuary were used to identify temporal patterns of estuarine temperature anomalies in the surface (</=1 m) and subsurface (>/=15 m) between 1949 and 2002. Data indicated a trend in surface and subsurface warming of +0.16 degrees C and +0.21 degrees C per decade, respectively, driven by warming during winter and spring. These trends suggest warming of the estuary since the mid-20th century of approximately 0.8-1.1 degrees C. Estuarine temperatures correlated well with other independent data records for sea surface and surface air temperatures in the region and to a lesser extent, the northern hemisphere. Gross long-term temperature variability in the estuary was consistent with North Atlantic climate variability associated with the prolonged positive North Atlantic Oscillation/Arctic Oscillation and increased anthropogenic radiative forcing, although localized environmental drivers likely are important as well. A simple spatial analysis revealed strong seasonal latitudinal and longitudinal gradients in estuarine temperature as well as a north-south gradient in long-term temperature trends. Continued warming of the estuary will have important implications for ecosystem structure and function as well as attempts to manage existing challenges such as eutrophication and benthic hypoxia. However, such management efforts must be cognizant of the effects of various climate and nonclimate drivers of environmental variability and change operating over different spatial and temporal scales.

Conservation of Natural Resources↗
PubMed2000

Horizontal heterogeneity of denitrifying bacterial communities in marine sediments by terminal restriction fragment length polymorphism analysis.

Although it is widely believed that horizontal patchiness exists in microbial sediment communities, determining the extent of variability or the particular members of the bacterial community which account for the observed differences among sites at various scales has not been routinely demonstrated. In this study, horizontal heterogeneity was examined in time and space for denitrifying bacteria in continental shelf sediments off Tuckerton, N.J., at the Rutgers University Long-Term Ecosystem Observatory (LEO-15). Characterization of the denitrifying community was done using PCR amplification of the nitrous oxide reductase (nosZ) gene combined with terminal restriction fragment length polymorphism analysis. Spatial scales from centimeters to kilometers were examined, while temporal variation was assayed over the course of 1995 to 1996. Sorenson's indices (pairwise similarity values) were calculated to permit comparison between samples. The similarities of benthic denitrifiers ranged from 0.80 to 0.85 for centimeter scale comparisons, from 0.52 to 0.79 for meter level comparisons, and from 0.23 to 0.53 for kilometer scale comparisons. Sorenson's indices for temporal comparisons varied from 0.12 to 0.74. A cluster analysis of the similarity values indicated that the composition of the denitrifier assemblages varied most significantly at the kilometer scale and between seasons at individual stations. Specific nosZ genes were identified which varied at centimeter, meter, or kilometer scales and may be associated with variability in meio- or macrofaunal abundance (centimeter scale), bottom topography (meter scale), or sediment characteristics (kilometer scale).

Cluster Analysis↗
PubMed2000

Spatial and temporal comparison of selected cancers in dogs and humans, Michigan, USA, 1964-1994.

Our aim was to investigate the geographic and time distributions of some biologically similar neoplasms in dogs and humans living in Michigan, USA, between 1964 and 1994. Our objective was to describe and compare the patterns of cancer in the two species while assessing the strength and dependence of those patterns. In this retrospective, registry-based study, histologically confirmed incident human and canine cancer cases were mapped, and second-order (K function) spatial analysis and one-dimensional nearest neighbor temporal analysis were performed on residence addresses and dates of hospital discharge/diagnosis. Included in the study were all 528 incident cases of canine lymphosarcoma, mammary adenocarcinoma, melanoma and spindle-cell sarcomas diagnosed at a veterinary teaching hospital between 1964 and 1994 having residence addresses in Ingham, Oakland, and Wayne Counties; and a stratified random sample of 913 incident human cases of comparable cancers diagnosed during the same time period from the same counties. Results suggest that processes determining spatial aggregation of cases in dogs and humans were not independent of each other, did not act uniformly over different geographic areas, operated at spatial scales <2000 m regardless of species, and tend to act upon dogs more strongly at shorter distances than on humans. Little evidence of interspecies concurrence of temporal clustering was found.

Adenocarcinoma↗
PubMed2002

Spatial patterns in benthic biodiversity of Chesapeake Bay, USA (1984-1999): association with water quality and sediment toxicity.

Non-point-source pollution is an increasing source of stress to aquatic, estuarine, and marine ecosystems. Such pollution may be of unknown etiology, distributed over extensive spatial scales, and comprised of multiple stressors. Current stressor-based paradigms for ecological risk assessment (ERA) may be insufficient to characterize risk from multiple stressors at regional spatial scales, necessitating the use of effects-based approaches. Historical data (1984-1999) for benthic macroinvertebrate biodiversity in Chesapeake Bay, USA, were incorporated into a geographic information system (GIS) and spatial analysis tools were used to model zones within the bay predicted to be of low or high anthropogenic impact. Data for benthic water quality and sediment toxicant concentrations from each of these zones were subsequently analyzed and compared to identify associations between benthic biodiversity and potential stressors. A number of stressors were significantly associated with high-impact zones, including increased nitrogen and phosphorus concentrations, low dissolved oxygen, heavy metals, pesticides, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. The spatial autocorrelation among multiple stressors suggests that traditional stressor-based approaches to ERA may result in the a priori exclusion of ecologically relevant stressors. Considering the effects of individual stressors rather than net effects of multiple stressors may result in underestimation of risk. The GISs are a useful tool for integrating multiple data sets in support of comprehensive regional ERA.

Animals↗
PubMed2003

Analysis of climate trends in North Carolina (1949-1998).

North Carolina has one of the most complex climates in the United States (U.S.). Analysis of the climate in this state is critical for agricultural and planning purposes. Climate patterns and trends in North Carolina are analyzed for the period 1949-1998. Precipitation, minimum temperature, and maximum temperature are analyzed on seasonal and annual time scales using data collected from the National Weather Service Cooperative Observer Network. Additionally, changes in patterns of occurrence of the last spring freeze and first fall freeze are investigated. Linear time series slopes are analyzed to investigate the spatial and temporal trends of climate variability in North Carolina. Spatial analysis of climate variability across North Carolina is performed using a geographic information system. While most trends are local in nature, there are general statewide patterns. Precipitation in North Carolina has increased over the past 50 years during the fall and winter seasons, but decreased during the summer. Temperatures during the last 10 years are warmer than average, but are not warmer than those experienced during the 1950s. The warm season has become longer, as measured by the dates of the last spring freeze and first fall freeze. Generally, the last 10 years were the wettest of the study period. These conclusions are consistent with earlier studies that show that the difference between the maximum and minimum temperatures is decreasing, possibly due to increased cloud cover and precipitation. Similarly, these results show that temperature patterns are in phase with the North Atlantic Oscillation and precipitation patterns appear to be correlated with the Pacific Decadal Oscillation.

Climate↗
PubMed1999

New insights into positional alcohol nystagmus using three-dimensional eye-movement analysis.

The semicircular canals selectively transduce angular velocity and are normally insensitive to gravity and linear acceleration. In acute alcohol intoxication, however, the cupula becomes lighter than the endolymph, rendering it sensitive to gravity (buoyancy hypothesis). This results in positional alcohol nystagmus (PAN) and rotatory vertigo. We evaluated PAN in 8 normal subjects by means of three-dimensional eye-movement analysis in an attempt to clarify if the buoyancy mechanism is sufficient to explain PAN. Forty minutes after intake of 0.8 g of alcohol/kg of body weight, the subjects were positioned such that the lateral canals were earth vertical. They were then rotated in the plane of the lateral canals about an earth-horizontal axis to either 45 degrees or 90 degrees , right or left ear down, and eye movements were recorded for 40 seconds in each position. The spatial analysis of the responses showed that in addition to the nystagmus induced by the buoyancy of all six cupulae, alcohol intoxication also causes a vertical velocity offset (in all subjects, slow phase down) that is independent of the orientation of the subject in space. The offset may represent a toxic effect on central vestibular pathways, producing a tone imbalance of the vertical vestibulo-ocular reflex.

Adult↗
PubMed1985

Spatial EEG patterns, non-linear dynamics and perception: the neo-Sherringtonian view.

Spatial analysis with preamplifier arrays and computers offers fresh perspectives on brain function. Realization of its potential depends on development of appropriate procedures for data processing and display, experimental paradigms to serve as benchmarks, and theories of brain function to predict what to look for and how to distinguish valid results from artifacts. Measurement of EEGs from arrays of 64 electrodes chronically implanted on the olfactory bulbs of rabbits that are trained to discriminate odorant conditioned stimuli show that the odorants induce spatially distinctive amplitude patterns of neural activity. The odor-specific information density is inferred to be uniform over the whole main bulb. The neural dynamics that produce these activity patterns emerge from the synaptically interactive sheet of excitatory mitral and inhibitory granule cells with distributed input and output tracts and with static nonlinearities deriving from the nerve impulse mechanism. Excitatory synapses between mitral cells are subject to modification when odorants are paired with unconditioned stimuli, thus forming nerve cell assemblies. Odorant-specific information established by a stimulus locally in the bulbar unit activity is integrated with past experience by an assembly, disseminated over the entire bulb on the order of 100 mm2 in area in a time period of 2.5 ms, and sustained for a time period on the order of 0.1 s. An arbitrary spatial sample on the order of 20% of bulbar EEG activity captures the entire integrated information albeit at lesser resolution than the whole. This synaptic mechanism of local input and global output may be common to all of the cerebral cortex. The implications are discussed for neocortical sensory systems, motor pattern generators, and goal-directed behavior in the context of self-organizing non-linear dynamic systems.

Aging↗
PubMed2005

Spatial QRS-T angle predicts cardiac death in a clinical population.

OBJECTIVES/BACKGROUND: The purpose of this study was to validate the prognostic value of computer-derived measurements of the spatial alignment of ventricular depolarization and repolarization from the standard 12-lead ECG in a general medical population. METHODS: Analyses were performed on the first ECG digitally recorded from 46,573 consecutive patients since 1987. QRS and T vector were synthesized by deriving XYZ leads from the 12 leads using the inverse Dower weighting matrix. Subset analyses were considered in patients with and those without standard ECG diagnoses (i.e., atrial fibrillation, Q waves, left ventricular hypertrophy, prolonged QRS duration). The main outcome measure was cardiovascular mortality. RESULTS: During a mean follow-up of 6 years, 4,127 cardiovascular deaths occurred. After adjusting for age, heart rate, and gender in a Cox regression analysis, spatial QRS-T angle was the most significant predictor of cardiovascular mortality, outperforming all other ECG measurements and diagnostic statements. In the subset with ECGs free of any standard diagnoses, annual cardiovascular mortality was 0.8% for normal (0-50 degrees ), 2.3% for borderline (50-100 degrees ), and 5.1% for abnormal (100-180 degrees ) QRS-T angle groups. The borderline and abnormal angle groups had 1.5- and 1.9-fold higher risk, respectively, relative to the normal QRS-T angle group after adjustment for age, gender, and heart rate. Similar results were found when patients with standard ECG diagnosis were included or compared. CONCLUSIONS: Spatial QRS-T angle is a significant and independent predictor of cardiovascular mortality that provides greater prognostic discrimination than any of the commonly utilized ECG diagnostic classifications.

Cardiovascular Diseases↗
PubMed2001

Spatially-resolved EELS analysis of multilayer using EFTEM and STEM.

Spatially-resolved electron energy-loss spectroscopy (EELS) is applied to the multilayer (SiO2/Si3N4/SiOxNy/Si), a common semiconductor device structure. To observe depth profile at sub-nanometre spatial resolution, scanning transmission electron microscopy (STEM) and energy-filtering transmission electron microscopy (EFTEM)-based techniques are compared in practical application. STEM-based EELS is useful in simultaneously analysing plural elements. EFTEM-based EELS is suitable for analysing the chemical shift and core loss intensity of single element. The practical spatial resolution is of the same order for each technique, both involving beam damage, which can be reduced by decreasing current density in EFTEM and avoiding beam overlapping in STEM.

Journal Article↗