Factors contributory to fire occurrences in two populated areas in the American southwest

PurposeThis study aims to further understand the factors contributory to fire occurrences in two semi-arid regions in the American Southwest, Clark County in Nevada and Maricopa and Pinal Counties in Arizona.Design/methodology/approachStatistical and geographic information system analyses were employed to examine the spatial and temporal relationships of various natural and human-caused factors with fire incidences.FindingsAngström fire danger index, average amount of rainfall one month prior, extent of forests and grasslands, and proximities to secondary roads and population centers have significant relationships with fire events.Research limitations/implicationsThe importance of the factors contributory to fire occurrence is site-specific even in areas with similar climatic regimes and varies among different geographic regions; as such, researchers will need to conduct specific investigation of each study area.Practical implicationsThe findings of this study can be instrumental in facilitating fire managers to derive more informed strategies in fire prevention and management.Originality/valueWhile there are many studies on fire, most of them are conducted in wet regions with a lot of vegetative cover; not much work is done on arid areas. This paper considered and compared the spatial and temporal relationships of a wide range of natural and human-caused factors with fire events in two semi-arid areas. The intent was to assess the relative importance of these factors in areas even with similar climatic regimes. As our world is facing unprecedented changes in terms of climate and population growth, it is paramount to have an enhanced understanding of the impacts of these changes on fire regimes. The study areas are hot and dry, and they are located in the wildland–urban interfaces with rapid population growth and urbanization; as such, the research findings may contribute to existing literature.

Impact of Safe@Home on Placement and Permanency Outcomes: Results of a quasi-experimental study

The purpose of this study was to rigorously test the effectiveness of Safe@Home, an in-home parent skill-based intervention implemented in Clark County, Nevada. Safe@Home is designed to prevent out-of-home placement for children at imminent risk of placement (Placement Prevention population) and minimize time in out-of-home care for children already in foster care (Reunification population). This paper presents a retrospective, longitudinal, quasi-experimental study that examined placement and permanency outcomes of Safe@Home. Using Coarsened Exact Matching (CEM), children who received Safe@Home were matched to a historical comparison group of children served before Safe@Home was available in their community. All children in the study were determined by Clark County Department of Family Services to be unsafe and in need of immediate intervention. Children were matched based on age, race/ethnicity, previous in-home or out-of-home child welfare case, and safety threats Matched study samples demonstrated strong baseline equivalence. Children who received Safe@Home experienced a significantly lower rate of out-of-home placements, substantially higher rate of permanency with a parent, fewer days in out-of-home care, and shorter time to case closure. There was no effect of Safe@Home on post-permanency outcomes of maltreatment after case closure and re-entry. Large favorable placement prevention effects were sustained for 12 months after the end of Safe@Home.

The Fires, Asian, and Stratospheric Transport-Las Vegas Ozone Study (FAST-LVOS)

The Fires, Asian, and Stratospheric Transport-Las Vegas Ozone Study (FAST-LVOS) was conducted in May and June of 2017 to study the transport of ozone (O3) to Clark County, Nevada, a marginal non-attainment area in the Southwestern U.S. (SWUS). This 6-week (20 May–30 June 2017) field campaign used lidar, ozonesonde, aircraft, and in-situ measurements in conjunction with a variety of models to characterize the distribution of O3 and related species above southern Nevada and neighbouring California, and to probe the influence of stratospheric intrusions, wildfires, and local, regional, and Asian pollution on surface O3 concentrations in Las Vegas and the surrounding area. In this paper, we describe the FAST-LVOS campaign and present case studies illustrating the influence of different transport processes on background O3 and air quality attainment in the SWUS. The measurements found elevated O3 layers above Las Vegas on more than 75 % (35 of 45) of the sample days, and show that entrainment of these layers contributed to mean 8-h average background O3 concentrations of 50–55 parts-per-billion by volume (ppbv) across southern Nevada. These background concentrations constitute 70–80 % of the current U.S. National Ambient Air Quality Standard (NAAQS) of 70 ppbv, and illustrate some of the challenges facing air quality managers tasked with O3 attainment in the SWUS during late spring and early summer. The companion paper by Zhang et al. (2020) describes the use of the AM4 and GEOS-Chem global models to estimate the impacts of transported O3 on surface air quality in the Southwestern U.S. and Intermountain West during the FAST-LVOS campaign.

Opioid-related hospitalizations and intravenous drug users: Sociodemographic, spatial, and comorbid associations among hospital inpatients and community-based harm reduction organization participants

Objective: To provide an updated analysis of opioid-related injuries in Nevada and provide a first-time analysis of the intravenous drug user (IDU) population within Clark County.Design: Cross-sectional study.Setting: Center for Health Information Analysis (CHIA) database and IDU data from Trac-B Exchange (Trac-B).Participants: Patients hospitalized for opioid-related causes (n = 9,064) and participants from Trac-B.Main outcome measure(s): Variables assessed included age, gender, and race/ethnicity. Zip codes were retrieved to find differences in geographical usage patterns of hospital or sterile injection equipment (SEP) sites. Contingency tables were utilized to determine the frequency of comorbidities. Additionally, GIS was used to investigate potential spatial patterns of interest.Results: Totally 5,268 out of the 9,064 opioid-related cases reported in Nevada were Clark County residents. The highest frequency for comorbidities associated with opioid-related hospitalizations (ORHs) included: infections, chronic bodily pain, and malnutrition. There was a higher proportion of 18-35-year-olds who used SEPs as compared to hospitals and a higher proportion of individuals aged 36 years or older who used hospitals as compared to using SEPs. Of the nearly 100 zip codes in Clark County, six showed a disproportionally high frequency of ORHs, and three comprised the majority of injection drug use.Conclusions: There is an opioid epidemic in Nevada that has contributed to addiction, heroin usage, injection drug use, and transmission of bloodborne diseases. Understanding the ORHs and intravenous drug use trends can help guide the development of program interventions.

Guidelines and pitfalls of refraction microtremor surveys

The geotechnical industry has widely adopted the refraction microtremor shear-wave velocity measurement technique, which is accepted by building authorities for evaluation of seismic site class around the world. Clark County and the City of Henderson, Nevada, populated their Earthquake Parcel Map with over 10,000 site measurements for building code enforcement, made over a 3-year period. 2D refraction microtremor analysis now allows engineers to image lateral shear-wave velocity variations and do passive subsurface imaging. Along with experience at a basic level, the ability to identify the “no energy area” and the “minimum-velocity envelope” on the slowness-frequency (p-f) image helps practitioners to assess the quality of their ReMi data and analysis. Guides for grading (p-f) image quality, and for estimating depth sensitivity, velocity-depth tradeoffs, and depth and velocity resolution also assist practitioners in deciding whether their refraction microtremor data will meet their investigation objectives. Commercial refraction microtremor surveys use linear arrays, and a new criterion of 2.2% minimum microtremor energy in the array direction allows users to assess the likelihood of correct results. Unfortunately, any useful and popular measurement technique can be abused. Practitioners must follow correct data collection, analysis, interpretation, and measurement procedures, or the results cannot be labeled “refraction microtremor” or “ReMi” results. We present some of the common mistakes and provide solutions with the objective of establishing a “best practices” template for getting consistent, reliable models from refraction microtremor measurements.

After Action Review of the 2019 measles outbreak in Clark County, Washington, U.S.A

Issue Clark County experienced a measles outbreak that challenged public health authorities. Description of the practice: We conducted a formal After Action Review with state and local health officials, school officials, and others to identify lessons for public health practitioners facing future outbreaks. Results Following the early identification of measles in a child who had recently arrived from Ukraine, active surveillance identified 71 confirmed cases, most in unvaccinated persons under 18 years of age. 4,138 contacts were traced and public health personnel made daily monitoring calls to 816. 53 potential exposure sites in healthcare facilities, schools and other public places were identified and communicated to the public. As a social distancing measure, unvaccinated students, teachers, and staff were excluded from schools in which exposure had occurred. Ascertaining susceptibility status was challenging. The national anti-vaccination sentiment and a parallel outbreak in a New York religious community created challenges in representing community risk while avoiding stigmatization of a community in which the first reported case was identified. Rather than respond to every false claim on social media, the health department developed talking points about emerging issues and engaged the community in dialogue. Lessons Responding to the measles outbreak required innovative approaches to surveillance and contact tracing, social distancing (school exclusions), and emergency risk communication. The response required extensive coordinated efforts of the county and state health departments, school systems, and many other organizations. Mutual aid enabled an influx of resources but managing the surge of responders proved challenging. Key messages Public health emergencies require effective emergency management practices. Carefully conducted After Action Reviews of health emergencies can help public health practitioners identify challenges and innovative practices.