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Dive into the research topics where James L. Regens is active.

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Featured researches published by James L. Regens.


Journal of Homeland Security and Emergency Management | 2006

Terrorist Attacks against Children: Vulnerabilities, Management Principles and Capability Gaps

James L. Regens

Events such as the 1995 Oklahoma City bombing and the 2004 terrorist attack on the school in Beslan, Russia demonstrate that terrorists are willing and able to attack large numbers of children. Moreover, pediatric casualties are likely when terrorist incidents occur in urban areas even if children are not the primary target. Very little research has been conducted on the management and outcomes of children during and after disasters. This paper discusses the known risks that terrorism brings to children, vulnerabilities in this population, basic principles of pediatric disaster response and current gaps in response capabilities.


Journal of Medical Entomology | 2005

Evaluation of environmental data for identification of Anopheles (Diptera: Culicidae) aquatic larval habitats in Kisumu and Malindi, Kenya

Benjamin G. Jacob; Kristopher L. Arheart; Daniel A. Griffith; Charles M. Mbogo; Andrew K. Githeko; James L. Regens; John I. Githure; Robert J. Novak; John C. Beier

Abstract This research evaluates the extent to which use of environmental data acquired from field and satellite surveys enhances predictions of urban mosquito counts. Mosquito larval habitats were sampled, and multispectral thermal imager (MTI) satellite data in the visible spectrum at 5-m resolution were acquired for Kisumu and Malindi, Kenya, during February and March 2001. All entomological parameters were collected from January to May 2001, June to August 2002, and June to August 2003. In a Poisson model specification, for Anopheles funestus Giles, shade was the best predictor, whereas substrate was the best predictor for Anopheles gambiae, and vegetation for Anopheles arabensis Patton. The top predictors found with a logistic regression model specification were habitat size for An. gambiae Giles, pollution for An. arabensis, and shade for An. funestus. All other coefficients for canopy, debris, habitat nature, permanency, emergent plants, algae, pollution, turbidity, organic materials, all MTI waveband frequencies, distance to the nearest house, distance to the nearest domestic animal, and all land use land cover changes were nonsignificant. MTI data at 5-m spatial resolution do not have an additional predictive value for mosquito counts when adjusted for field-based ecological data.


Health Promotion Practice | 2008

Implications of Public Understanding of Avian Influenza for Fostering Effective Risk Communication

Brenda L. Elledge; Michael W. Brand; James L. Regens; Daniel T. Boatright

Avian influenza has three of the four properties necessary to cause a pandemic. However, are we as individuals and communities prepared for a pandemic flu in the United States? To help answer this question, 12 focus groups (N = 60) were conducted in Tulsa, Oklahoma, to determine the level of awareness of avian and pandemic flu for the county health department to develop effective communication messages. The overall findings indicate that the general Tulsa public lacks information about avian influenza or pandemics, does not believe a pandemic will occur, and believes if one does occur the government will take care of it. Finally, the groups agreed that education would be the key to preventing widespread panic if a pandemic occurred. Five themes emerged: confusion about terminology, seriousness of avian influenza, disaster fatigue, appropriate precautions, and credibility of health information. Each should be considered in developing effective risk communication messages.


International Journal of Health Geographics | 2008

Hydrological modeling of geophysical parameters of arboviral and protozoan disease vectors in Internally Displaced People camps in Gulu, Uganda.

Benjamin G. Jacob; Ephantus J. Muturi; Erick X. Caamano; James T. Gunter; Enoch Mpanga; Robert Ayine; Joseph Okello-Onen; Jack Pen-Mogi Nyeko; Josephat Shililu; John I. Githure; James L. Regens; Robert J. Novak; Ibulaimu Kakoma

BackgroundThe aim of this study was to determine if remotely sensed data and Digital Elevation Model (DEM) can test relationships between Culex quinquefasciatus and Anopheles gambiae s.l. larval habitats and environmental parameters within Internally Displaced People (IDP) campgrounds in Gulu, Uganda. A total of 65 georeferenced aquatic habitats in various IDP camps were studied to compare the larval abundance of Cx. quinquefasciatus and An. gambiae s.l. The aquatic habitat dataset were overlaid onto Land Use Land Cover (LULC) maps retrieved from Landsat imagery with 150 m × 150 m grid cells stratified by levels of drainage. The LULC change was estimated over a period of 14 years. Poisson regression analyses and Morans I statistics were used to model relationships between larval abundance and environmental predictors. Individual larval habitat data were further evaluated in terms of their covariations with spatial autocorrelation by regressing them on candidate spatial filter eigenvectors. Multispectral QuickBird imagery classification and DEM-based GIS methods were generated to evaluate stream flow direction and accumulation for identification of immature Cx. quinquefasciatus and An. gambiae s.l. and abundance.ResultsThe main LULC change in urban Gulu IDP camps was non-urban to urban, which included about 71.5 % of the land cover. The regression models indicate that counts of An. gambiae s.l. larvae were associated with shade while Cx. quinquefasciatus were associated with floating vegetation. Morans I and the General G statistics for mosquito density by species and instars, identified significant clusters of high densities of Anopheles; larvae, however, Culex are not consistently clustered. A stepwise negative binomial regression decomposed the immature An. gambiae s.l. data into empirical orthogonal bases. The data suggest the presence of roughly 11% to 28 % redundant information in the larval count samples. The DEM suggest a positive correlation for Culex (0.24) while for Anopheles there was a negative correlation (-0.23) for a local model distance to stream.ConclusionThese data demonstrate that optical remote sensing; geostatistics and DEMs can be used to identify parameters associated with Culex and Anopheles aquatic habitats.


Malaria Journal | 2009

Patterns of Plasmodium vivax and Plasmodium falciparum malaria underscore importance of data collection from private health care facilities in India

Sangeeta Gupta; James T. Gunter; Robert J. Novak; James L. Regens

BackgroundThis study describes patterns of falciparum and vivax malaria in a private comprehensive-care, multi-specialty hospital in New Delhi from July 2006 to July 2008.MethodsMalarial morbidity by Plasmodium species (Plasmodium falciparum, Plasmodium vivax, or Plasmodium sp.) was confirmed using microscopy and antigen tests. The influence of seasonal factors and selected patient demographics on morbidity was evaluated. The proportions of malaria cases caused by P. falciparum at the private facility were compared to data from Indias National Vector Borne Disease Control Programme (NVBDCP) during the same period for the Delhi region.ResultsIn New Delhi, P. faciparum was the dominant cause of cases requiring treatment in the private hospital during the period examined. The national data reported a smaller proportion of malaria cases caused by P. falciparum in the national capital region than was observed in a private facility within the region. Plasmodium vivax also caused a large proportion of the cases presenting clinically at the private hospital during the summer and monsoon seasons.ConclusionThe proportion of P. falciparum malaria cases tends to be greatest during the post-monsoon season while the proportion of P. vivax malaria cases tends to be greatest in the monsoon season. Private hospital data demonstrate an under-reporting of malaria case incidences in the data from Indias national surveillance programme during the same period for the national capital region.


International Journal of Health Geographics | 2006

Spatially targeting Culex quinquefasciatus aquatic habitats on modified land cover for implementing an Integrated Vector Management (IVM) program in three villages within the Mwea Rice Scheme, Kenya

Benjamin G Jacob; Josephat Shililu; Ephantus J. Muturi; Joseph M. Mwangangi; Simon Muriu; Jose Funes; John I. Githure; James L. Regens; Robert J. Novak

BackgroundContinuous land cover modification is an important part of spatial epidemiology because it can help identify environmental factors and Culex mosquitoes associated with arbovirus transmission and thus guide control intervention. The aim of this study was to determine whether remotely sensed data could be used to identify rice-related Culex quinquefasciatus breeding habitats in three rice-villages within the Mwea Rice Scheme, Kenya. We examined whether a land use land cover (LULC) classification based on two scenes, IKONOS at 4 m and Landsat Thematic Mapper at 30 m could be used to map different land uses and rice planted at different times (cohorts), and to infer which LULC change were correlated to high density Cx. quinquefasciatus aquatic habitats. We performed a maximum likelihood unsupervised classification in Erdas Imagine V8.7® and generated three land cover classifications, rice field, fallow and built environment. Differentially corrected global positioning systems (DGPS) ground coordinates of Cx. quinquefasciatus aquatic habitats were overlaid onto the LULC maps generated in ArcInfo 9.1®. Grid cells were stratified by levels of irrigation (well-irrigated and poorly-irrigated) and varied according to size of the paddy.ResultsTotal LULC change between 1988–2005 was 42.1 % in Kangichiri, 52.8 % in Kiuria and and 50.6 % Rurumi. The most frequent LULC changes was rice field to fallow and fallow to rice field. The proportion of aquatic habitats positive for Culex larvae in LULC change sites was 77.5% in Kangichiri, 72.9% in Kiuria and 73.7% in Rurumi. Poorly – irrigated grid cells displayed 63.3% of aquatic habitats among all LULC change sites.ConclusionWe demonstrate that optical remote sensing can identify rice cultivation LULC sites associated with high Culex oviposition. We argue that the regions of higher Culex abundance based on oviposition surveillance sites reflect underlying differences in abundance of larval habitats which is where limited control resources could be concentrated to reduce vector larval abundance.


Infection and Immunity | 2008

Bacillus anthracis Edema Toxin Activates Nuclear Glycogen Synthase Kinase 3β

Jason L. Larabee; Kevin DeGiusti; James L. Regens; Jimmy D. Ballard

ABSTRACT Bacillus anthracis edema toxin (ET) generates high levels of cyclic AMP and impacts a complex network of signaling pathways in targeted cells. In the current study, we sought to identify kinase signaling pathways modulated by ET to better understand how this toxin alters cell physiology. Using a panel of small-molecule inhibitors of mammalian kinases, we found that inhibitors of glycogen synthase kinase 3 beta (GSK-3β) protected cells from ET-induced changes in the cell cycle. GSK-3β inhibitors prevented declines in cellular levels of cyclin D1 and c-Jun following treatment of macrophages with ET. Strikingly, cell fractionation experiments and confocal immunofluorescence microscopy revealed that ET activates a compartmentalized pool of GSK-3β residing in the nuclei, but not in the cytoplasm, of macrophages. To investigate the outcome of this event, we examined the cellular location and activation state of β-catenin, a critical substrate of GSK-3β, and found that the protein was inactivated within the nucleus following intoxication with ET. To determine if ET could overcome the effects of stimuli that inactivate GSK-3β, we examined the impact of the toxin on the Wnt signaling pathway. The results of these experiments revealed that by targeting GSK-3β residing in the nucleus, ET circumvents the upstream cytoplasmic inactivation of GSK-3β, which occurs following exposure to Wnt-3A. These findings suggest ET arrests the cell cycle by a mechanism involving activation of GSK-3β residing in the nucleus, and by using this novel mechanism of intoxication, ET avoids cellular systems that would otherwise reverse the effects of the toxin.


Journal of Medical Entomology | 2005

Anopheles gambiae s.l. and Anopheles funestus Mosquito Distributions at 30 Villages along the Kenyan Coast

Joseph Keating; Charles M. Mbogo; Joseph M. Mwangangi; Joseph G. Nzovu; Weidong Gu; James L. Regens; Guiyun Yan; John I. Githure; John C. Beier

Abstract This study investigated whether Anopheles gambiae s.l. and Anopheles funestus Giles mosquito populations were distributed randomly among houses on the coast of Kenya. Sample means and variances of mosquitoes were estimated from bimonthly pyrethrum spray collections at 30 villages from July 1997 through May 1998. In total, 5,476 An. gambiae s.l. and 3,461 An. funestus were collected. The number of An. gambiae s.l. collected was highest in November/December and lowest in May. The number of An. funestus collected was highest during September/October and lowest during May. As the density of mosquitoes decreased, there was a tendency toward randomness in the distribution. The proportion of An. gambiae s.l. and An. funestus mosquitoes collected per house for each sampling period also showed patterns of clustering, with 80% of An. gambiae s.l. collected from <30% of the houses and 80% of An. funestus collected from <20% of the total houses. The total number of mosquitoes collected from any one house ranged from 0 to 121 for An. gambiae s.l. and from 0 to 152 for An. funestus. This coupled with the results of the variance to mean ratio plots suggests extensive clustering in the distribution of An. gambiae s.l. and An. funestus mosquito populations throughout the year along the coast of Kenya.


Journal of Soils and Sediments | 2004

Environmental persistence of 2,3,7,8-tetrachlorodibenzo-p-dioxin in soil around Hardstand 7 at Eglin Air Force Base, Florida

Astrid P. Vásquez; James L. Regens; James T. Gunter

Background and GoalA number of global events have generated intense scientific scrutiny and public concern of polychlorinated dibenzo-p-dioxins (dioxin). DIoxins have been associated with a range of adverse health effects. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is recognized as among the most dangerous of the dioxin compounds, and was a contaminant found In one of the herbicides used for vegetation control during the Vietnam conflict: Agent Orange. As a result of purging spray systems and leaking drums of Agent Orange concentrate, TCDD contamination occurred in the soils surrounding Hardstand 7 at Eglin Air Force Base, Florida. This research uses a multimedia model to estimate the TCDD concentrations in surface soil around Hardstand 7 for a 70-year time Interval beginning with observed surface soil concentrations 1984.MethodsHardstand 7 is a nearly 40-m circular concrete and asphalt aircraft parking area. The hardstand was used as a staging area for spraying equipment used to disseminate herbicide In a test area called C-52A within EAFB. Concentrated herbicide was also stored in 208-L barrels for use with the equipment, and later, for disposal. In 1984, a field investigation characterized the extent of TCDD contamination in surface soils around Hardstand 7 using a radial sampling protocol. The 1984 observed concentrations and locations was used in a multimedia model, CalTOX, as an initial source term concentrations and locations to estimate expected concentrations during the subsequent 70-years.ResultsThe results indicate that more than 94% of the TCDD observed in surface soils 1984 will remain after a 70-year period. Access restrictions and remediation activities at the site eliminate bar verification of the CalTOX estimates. Conclusions. TCDD is highly persistent in the soil medium and natural attenuation may not produce a significant decrease In soil concentrations.RecommendationActive remediation actions may be required to prevent exposure to TCDD contamination surface soils. Verifying CalTOX concentration estimates an Important step that should be performed, however, the, model provides an easy to use tool to estimate TCDD surface soil contamination at herbicide storage or dispersion staging sites.


Transactions in Gis | 2008

A Spatial Filtering Specification for an Auto‐negative Binomial Model of Anopheles arabiensis Aquatic Habitats

Benjamin G. Jacob; Daniel A. Griffith; James T. Gunter; Ephantus J. Muturi; Erick X. Caamano; Josephat Shililu; John I. Githure; James L. Regens; Robert J. Novak

This research accounts for spatial autocorrelation by including latent map pattern components as predictor variables in a malaria mosquito aquatic habitat model specification. The data used to derive the model was from a digitized grid-based algorithm, generated in an ArcInfo database, using QuickBird visible and near-infrared (NIR) data. The Feature Extraction (FX) Module in ENVI 4.4® was used to categorize individual pixels of field sampled aquatic habitats into separate spectral classes, convert remotely sensed raster layers to vector coverages, and classify output layers to vector format as ESRI shapefiles. These data were used to construct a geographic weights matrix for evaluation of field and remote sampled covariates of Anopheles arabiensis aquatic habitats, a major vector of malaria in East Africa. The principal finding is that synthetic map pattern variables, which are eigenvectors computed for a geographic weights matrix, furnish an alternative way of capturing spatial dependency effects in the mean response term of a regression model. The spatial autocorrelation components suggest the presence of roughly 11 to 28% redundant information in the aquatic habitat larval count samples. The presence of redundant information in the models suggest that the sampling configuration of the An. arabiensis aquatic habitats, in the study sites, may cause field and remote observations of aquatic habitats to be dependent, rather than independent, moving data analysis away from the classical statistical independence model. A Poisson regression model, with a non-constant, gamma-distributed mean, can decompose field and remote sampled An. arabiensis data into positive and negative spatial autocorrelation eigenvectors, which can assess the precision of a malaria mosquito aquatic habitat map and the significance of all factors associated with larval abundance and distribution in a riceland agroecosystem.

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James T. Gunter

University of Oklahoma Health Sciences Center

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Nick Mould

University of Oklahoma Health Sciences Center

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Robert J. Novak

University of Alabama at Birmingham

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John I. Githure

International Centre of Insect Physiology and Ecology

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Benjamin G. Jacob

University of Alabama at Birmingham

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Carl Jensen

University of Mississippi

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Erick X. Caamano

University of Alabama at Birmingham

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Jimmy D. Ballard

University of Oklahoma Health Sciences Center

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Josephat Shililu

International Centre of Insect Physiology and Ecology

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