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The National Visitor Use Monitoring (NVUM) program data underlies estimates of the volume of recreation use of the National Forest System. The data also enable estimation of both the local economic contributions and nonmarket benefits of that visitation. Applications include evaluating the effects of natural disasters, site characteristics, and climate change, as well as expenditure and benefit transfers. This article describes the history and science background of the NVUM program, outlines the methods used in estimating market and nonmarket economic outcomes, and lists some examples of results found in the literature.
The mean dynamics in oscillatory channel flow is examined to investigate the dynamical mechanisms underlying the transition to turbulence in oscillatory wall-bounded flow. The analyses employ direct numerical simulation data acquired at three Stokes Reynolds numbers:
, 801 and 1009, where the lower
flow is transitional over the entire cycle and the two higher
flows exhibit flow characteristics similar to steady turbulent wall-bounded flow during part of the cycle. The flow evolution over a half-period of oscillation for all three
is as follows: near-wall streamwise velocity streaks develop during the early accelerating portion of the cycle; then at some later point in the cycle that depends on
, the near-wall streaks breakdown (demarking the onset of the nonlinear development stage), and the near-wall Reynolds stress grows explosively; the Reynolds stress remains elevated for part of the cycle before diminishing (yet remaining finite) during the late decelerating portion of the cycle. This process is then repeated indefinitely. The present findings demonstrate that transition to turbulence occurs when the nonlinear development stage begins during the accelerating portion of the cycle. This crucially leads to the diminishing importance of the centreline momentum source, the emergence of a locally accelerating/decelerating internal layer centred about the edge of the Stokes layer and the wall-normal rearrangement of the mean forces prior to the start of the decelerating portion of the cycle. The rearrangement of mean forces culminates in a four layer structure in the mean balance of forces. This is significant on a number of accounts since empirical and theoretical evidence suggests that the formation of a four layer structure is an important characteristic of a self-similar hierarchal structure that underlies logarithmic dependence of the mean velocity profile in steady turbulent wall-bounded flows (Klewicki et al., J. Fluid Mech., vol. 638, 2009, pp. 73–93). When the nonlinear development stage begins during the decelerating portion of the cycle (i.e. at
), a four layer structure is not observed in the mean balance of forces and the flow remains weakly transitional over the entire cycle.
To estimate the prevalence and sociodemographic characteristics of youth and young adults in major Canadian cities with self-reported vegetarian dietary practices and examine efforts to alter their diets.
Data were collected in autumn 2016 via web-based surveys. Respondents reported vegetarian dietary practices (vegan, vegetarian or pescatarian) and efforts in the preceding year to consume more or less of several nutrients, food groups and/or foods with particular attributes. Logistic regression models examined sociodemographic correlates of each vegetarian dietary practice and differences in other eating practices by diet type.
Participants were recruited from five major Canadian cities.
Youth and young adults, aged 16–30 years (n 2566).
Overall, 13·6 % of respondents reported vegetarian dietary practices: 6·6 % vegetarian, 4·5 % pescatarian and 2·5 % vegan. Sex, race/ethnicity, self-reported frequency of using the Nutrition Facts table and health literacy were significantly correlated with self-reported vegetarian dietary practice (P < 0·01 for all). Efforts to consume more fruits and vegetables (66·8 %) and protein (54·8 %), and less sugar (61·3 %) and processed foods (54·7 %), were prevalent overall. Respondents with vegetarian dietary practices were more likely to report efforts to consume fewer carbohydrates and animal products, and more organic, locally produced, ethically sourced/sustainably sourced/fair trade and non-GM foods (P < 0·01 for all), compared with those without these reported dietary practices.
Nearly 14 % of the sampled youth and young adults in major Canadian cities reported vegetarian dietary practices and may be especially likely to value and engage in behaviours related to health-conscious diets and sustainable food production.
We develop rapid chemical vapor sensors and micro gas chromatography (μGC) analyzers based on the optofluidic ring resonator (OFRR). An OFRR is a micro-sized thin-walled glass capillary; the circular cross-section of the capillary acts as an optical ring resonator while the whispering gallery modes or circulating waveguide modes (WGMs) supported by the ring resonator interact with the vapor samples passing through the capillary. The OFRR interior surface is coated with a vapor-sensitive polymer. The analyte and polymer interaction causes the polymer refractive index (RI) and the thickness to change, which is detected as a WGM spectral shift. Owing to the excellent fluidics, the OFRR vapor sensor exhibits sub-second detection and recovery time with a flow rate of 1 mL/min. On-column separation and detection in the OFRR based μGC system is also demonstrated, showing efficient separation of vapor mixtures and presenting highly reproducible retention time for the individual analyte. Compared to the conventional GC system, the OFRR μGC has the advantage of small size, rapid response, and high selectivity over a short length of column.
We describe the design and deployment of GREENBURST, a commensal Fast Radio Burst (FRB) search system at the Green Bank Telescope. GREENBURST uses the dedicated L-band receiver tap to search over the 960–1 920 MHz frequency range for pulses with dispersion measures out to
. Due to its unique design, GREENBURST is capable of conducting searches for FRBs when the L-band receiver is not being used for scheduled observing. This makes it a sensitive single pixel detector capable of reaching deeper in the radio sky. While single pulses from Galactic pulsars and rotating radio transients will be detectable in our observations, and will form part of the database we archive, the primary goal is to detect and study FRBs. Based on recent determinations of the all-sky rate, we predict that the system will detect approximately one FRB for every 2–3 months of continuous operation. The high sensitivity of GREENBURST means that it will also be able to probe the slope of the FRB fluence distribution, which is currently uncertain in this observing band.
Burning postharvest sugarcane residue is a standard practice to remove extraneous leaf material before spring regrowth. Live-fires were simulated from field-collected postharvest sugarcane residue and seeds of divine nightshade and itchgrass were exposed to dry and moistened postharvest residue (PHR) at four densities (6.1, 12.1, 18.2, and 24.2 Mg ha−1) and a nonburned control. The moisture content of residue exposed to simulated rainfall was 14% more in Experiment 2 than Experiment 1; however, burning PHR with 44% moisture when wind speeds were lower allowed the fire to continue and created a smoldering effect that reduced weed emergence by 23% when compared with burning PHR with 30% moisture during breezy conditions. The moistened 6.1 Mg ha−1 PHR treatment resulted in 53% more divine nightshade and itchgrass emergence when compared with dry 6.1 Mg ha−1 PHR after burning, and greater emergence was attributed to more seed survival for divine nightshade than itchgrass. The PHR moisture condition failed to influence the burn duration; however, the burn duration increased 103% and 56% as the amount of PHR increased from 6.1 to 12.1 Mg ha−1 and 12.1 to 18.2 Mg ha−1, respectively. The combination of high wind speeds and moistened PHR did not enhance the maximum burn temperature near the soil surface, but surface-deposited divine nightshade and itchgrass seeds were susceptible to prolonged exposure times at 100 C. Burning PHR from fields with poor stands or older ratoon, especially when PHR is abundantly wet, will not produce temperatures lethal to divine nightshade and itchgrass seeds. The fluid-filled and fleshy content that comprises divine nightshade fruit protected seed from short durations of high temperatures, but may not insulate seeds long enough when exposed to a smoldering fire.
The understanding of the genetic basis of grain dormancy in wheat has rapidly improved in the last few years, and a number of genes have been identified related to that trait. We recently identified the wheat genes TaPM19-A1 and -A2 and we have now taken the first step towards understanding the role of this class of genes in seeds. By investigating the Arabidopsis homologous PM19-Like 1 (PM19L1) we have found that it has a seed-specific expression pattern and, while its expression is higher in dormant than in non-dormant seeds, knock-out mutations produced seeds with increased dormancy. Not only primary dormancy, but also secondary dormancy in response to high temperature was increased by the loss-of-function. We have also examined the function of PM19L1 by localizing the PM19 protein primarily to the cotyledon cells in seeds, possibly in membranes. By investigating the co-expression network of this gene we have found that it is connected to a small group of abscisic acid (ABA)-induced seed maturation and storage-related genes. The function of PM19L1 represents a good opportunity to explore the interactions of key factors that can influence seed dormancy such as ABA, temperature and membrane properties.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Multisite intervention studies have become increasingly common in infection control, for example, looking for a change in hospital infection rates after a regional policy change. The design of these studies can take various forms, from pre–post observational studies to randomized trials, in which sites are randomly assigned to the intervention or in which the intervention is sequentially introduced to different sites over time. Data collected under these settings are clustered by hospital and/or ward, consist of repeated measurements and, in some cases, exhibit temporal and/or seasonal patterns. Failure to account for these features in data analysis could well result in biased estimates of intervention effectiveness and impact on the generalizability of model results.
Background: Hereditary transthyretin-mediated (hATTR) amyloidosis is a multi-systemic, heterogenous, life-threatening disease. Patisiran resulted in significant improvement in neuropathy and QoL at 18-months compared to placebo, and was generally well-tolerated in the Phase 3 APOLLO study. Methods: Multi-center, OLE study to evaluate the efficacy and safety of long-term patisiran dosing for ≤ 5 years in hATTR amyloidosis patients with polyneuropathy who have completed the APOLLO study (NCT02510261). Endpoints include safety, tolerability and long-term efficacy of patisiran. Measures of clinical benefit are the same endpoints used in APOLLO including changes in mNIS+7 composite neuropathy impairment score and QoL (Norfolk QoL-DN) Results: As of December 2017, 184 of 186 (99%) patients who completed APOLLO and 25 patients from the Ph 2 OLE study enrolled in the Global OLE study. Baseline data for 211(APOLLO/placebo, n=49; APOLLO/patisiran, n=137 and patisiran Ph 2 OLE, n=25) patients included: median age 61 years (26-84); 74% males; 46% V30M. Interim safety data and 12-month efficacy results will be presented. Conclusions: The global OLE study includes a diverse population of hATTR amyloidosis patients. Interim data will include the long-term safety and maintenance of effect in patients continuing on patisiran, as well as the impact of treatment with patisiran on patients previously treated with placebo.
Decreases in cognitive function related to increases in oxidative stress and inflammation occur with ageing. Acknowledging the free radical-quenching activity and anti-inflammatory action of the carotenoid lycopene, the aim of the present review was to assess if there is evidence for a protective relationship between lycopene and maintained cognitive function or between lycopene and development or progression of dementia. A systematic literature search identified five cross-sectional and five longitudinal studies examining these outcomes in relation to circulating or dietary lycopene. Among four studies evaluating relationships between lycopene and maintained cognition, three reported significant positive relationships. Neither of the two studies reporting on relationship between lycopene and development of dementia reported significant results. Of four studies investigating circulating lycopene and pre-existing dementia, only one reported significant associations between lower circulating lycopene and higher rates of Alzheimer's disease mortality. Acknowledging heterogeneity among studies, there is insufficient evidence and a paucity of data to draw firm conclusions or tease apart direct effects of lycopene. Nevertheless, as low circulating lycopene is a predictor of all-cause mortality, further investigation into its relationship with cognitive longevity and dementia-related mortality is warranted.
Fatigue syndromes (FSs) affect large numbers of individuals, yet evidence from epidemiological studies on adverse outcomes, such as premature death, is limited.
Cohort study involving 385 general practices in England that contributed to the Clinical Practice Research Datalink (CPRD) with linked inpatient Hospital Episode Statistics (HES) and Office for National Statistics (ONS) cause of death information. A total of 10 477 patients aged 15 years and above, diagnosed with a FS during 2000–2014, were individually matched with up to 20 comparator patients without a history of having a FS. Prevalence ratios (PRs) were estimated to compare the FS and comparison cohorts on clinical characteristics. Adjusted hazard ratios (HRs) for subsequent adverse outcomes were estimated from stratified Cox regression models.
Among patients diagnosed with FSs, we found elevated baseline prevalence of: any psychiatric illness (PR 1.77; 95% CI 1.72–1.82), anxiety disorders (PR 1.92; 1.85–1.99), depression (PR 1.89; 1.83–1.96), psychotropic prescriptions (PR 1.68; 1.64–1.72) and comorbid physical illness (PR 1.28; 1.23–1.32). We found no significant differences in risks for: all-cause mortality (HR 0.99; 0.91–1.09), natural death (HR 0.99; 0.90–1.09), unnatural death (HR 1.00; 0.59–1.72) or suicide (HR 1.68; 0.78–3.63). We did, however, observe a significantly elevated non-fatal self-harm risk: HR 1.83; 1.56–2.15.
The absence of elevated premature mortality risk is reassuring. The raised prevalence of mental illness and increased non-fatal self-harm risk indicate a need for enhanced assessment and management of psychopathology associated with fatigue syndromes.
A power MOSFET-based push–pull configuration nanosecond-pulse generator has been designed, constructed, and characterized to permeabilize cells for biological and medical applications. The generator can deliver pulses with durations ranging from 80 ns up to 1 µs and pulse amplitudes up to 1.4 kV. The unit has been tested for in vitro experiments on a medulloblastoma cell line. Following the exposure of cells to 100, 200, and 300 ns electric field pulses, permeabilization tests were carried out, and viability tests were conducted to verify the performance of the generator. The maximum temperature rise of the biological load was also calculated based on Joule heating energy conservation and experimental validation. Our results indicate that the developed device has good capabilities to achieve well-controlled electro-manipulation in vitro.
Icequakes at or near the bed of a glacier have the potential to allow us to investigate the interaction of ice with the underlying till or bedrock. Understanding this interaction is important for studying basal sliding of glaciers and ice streams, a critical process in ice dynamics models used to constrain future sea-level rise projections. However, seismic observations on glaciers can be dominated by seismic energy from surface crevassing. We present a method of automatically detecting basal icequakes and discriminating them from surface crevassing, comparing this method to a commonly used spectrum-based method of detecting icequakes. We use data from Skeidararjökull, an outlet glacier of the Vatnajökull Ice Cap, South-East Iceland, to demonstrate that our method outperforms the commonly used spectrum-based method. Our method detects a higher number of basal icequakes, has a lower rate of incorrectly identifying crevassing as basal icequakes and detects an additional, spatially independent basal icequake cluster. We also show independently that the icequakes do not originate from near the glacier surface. We conclude that the method described here is more effective than currently implemented methods for detecting and discriminating basal icequakes from surface crevassing.
Introduction: Identification of latent safety threats (LSTs) in the emergency department is an important aspect of quality improvement that can lead to improved patient care. In situ simulation (ISS) takes place in the real clinical environment and multidisciplinary teams can participate in diverse high acuity scenarios to identify LSTs. The purpose of this study is to examine the influence that the profession of the participant (i.e. physician, registered nurse, or respiratory therapist) has on the identification of LSTs during ISS. Methods: Six resuscitation- based adult and pediatric simulated scenarios were developed and delivered to multidisciplinary teams in the Kingston General Hospital ED. Each ISS session consisted of a 10- minute scenario, followed by 3-minutes of individual survey completion and a 7- minute group debrief led by ISS facilitators. An objective assessor recorded LSTs identified during each debrief. Surveys were completed prior to debrief to reduce response bias. Data was collected on participant demographics and perceived LSTs classified in the following categories: medication; equipment; resources and staffing; teamwork and communication; or other. Two reviewers evaluated survey responses and debrief notes to formulate a list of unique LSTs across scenarios and professions. The overall number and type of LSTs from surveys was identified and stratified by health care provider. Results: Thirteen ISS sessions were conducted with a total of 59 participants. Thirty- four unique LSTs (8 medication, 15 equipment, 5 resource, 4 communication, and 2 miscellaneous issues) were identified from surveys and debrief notes. Overall, MDs (n = 12) reported 19 LSTss (n = 41) reported 77 LSTs, and RTs (n = 6) reported 4 LSTs based on individual survey data. The most commonly identified category of LSTs reported by MDs (36.8%) and RTs (75%) was equipment issues while RNs most commonly identified medication issues (36.4%). Participants with □5 years of experience in their profession, on average identified more LSTs in surveys than participants with >5 years experience (1.9 LSTs vs 1.5 LSTs respectively). Conclusion: Nursing staff identified the highest number of LSTs across all categories. There was fairly unanimous identification of major LSTs across professions, however each profession did identify unique perspectives on LSTs in survey responses. ISS programs with the purpose of LST identification would benefit from multidisciplinary participation.
A 2018 workshop on the White Mountain Apache Tribe lands in Arizona examined ways to enhance investigations into cultural property crime (CPC) through applications of rapidly evolving methods from archaeological science. CPC (also looting, graverobbing) refers to unauthorized damage, removal, or trafficking in materials possessing blends of communal, aesthetic, and scientific values. The Fort Apache workshop integrated four generally partitioned domains of CPC expertise: (1) theories of perpetrators’ motivations and methods; (2) recommended practice in sustaining public and community opposition to CPC; (3) tactics and strategies for documenting, investigating, and prosecuting CPC; and (4) forensic sedimentology—uses of biophysical sciences to link sediments from implicated persons and objects to crime scenes. Forensic sedimentology served as the touchstone for dialogues among experts in criminology, archaeological sciences, law enforcement, and heritage stewardship. Field visits to CPC crime scenes and workshop deliberations identified pathways toward integrating CPC theory and practice with forensic sedimentology’s potent battery of analytic methods.
I examine the ability of the U.S. investor protection regime to limit insider trading returns, absent Section 16(b) of the Securities Exchange Act of 1934 (the short-swing rule). I find that in this setting, U.S. insiders execute short-swing trades that i) beat the market by approximately 15 basis points per day and ii) systematically divest ahead of disappointing earnings announcements. These results indicate that the bright-line rule restricting short-horizon round-trip insider trading plays a substantial role in protecting outside investors from privately informed insiders in the United States.
The principal aim of this study was to develop, pilot and evaluate an intervention intended to support the development of resilience and self-efficacy in parents of children with disabilities or complex health needs.
Previous research has found that families often experience physical, social and emotional stress in the context of living with and caring for their disabled child. The literature indicates that a key factor in determining how well the parents of these children cope with their situation may be how resilient and self-efficacious they are.
A total of 16 parents of children with complex needs and disabilities were engaged in a series of guided conversations delivered during six contact visits with nurse co-researchers (community children’s nurses who had received an intensive three-day preparation programme). The conversations, which were supported with additional material that was designed specifically for use in the study, were based around four key themes: emotional coping, practical coping, support networks and ‘you and your child’. The impact of the intervention was evaluated using both qualitative and quantitative measures.
When interviewed, parents reported increased self-belief and self-confidence and indicated that they felt better supported and stronger as a result of the intervention. This was consistent with the quantitative evaluation which identified significant improvements on scores for active coping and self-blame on the brief COPE inventory scale and for empathy and understanding and self-acceptance on the TOPSE scale. Scores on the self-report distress thermometer demonstrated a significant reduction in self-reported distress scores at the end of the intervention period.