245 research outputs found
Forest Management and the Dead Wood Resource in Ponderosa Pine Forests: Effects on Small Mammals
Changes in vegetation structure and composition affect habitat for wildlife. Species such as small mammals that are restricted to small home ranges and are relatively immobile may be most affected since it is more difficult to find and move to new habitat. In the southwestern United States, forest management treatments (thinning and prescribed burning) are being implemented to alter structure and function of ponderosa pine (Pinus ponderosa) ecosystems and recreate pre-settlement (ca. 1870) tree species composition and size class distribution. These forest restoration treatments will affect the availability of dead wood to wildlife (e.g., prescribed fires may consume dead wood, forest operations may create snags and logs). I livetrapped small mammals in a northern Arizona ponderosa pine forest prior to restoration treatment and found that mouse species (Peromyscus species) were associated with some dead wood elements (e.g., Gambel oak [Quercus gambelii] snags, ponderosa pine snags, ponderosa pine stumps)
Working paper 23: Guidelines for managing small mammals in restored ponderosa pine forests of northern Arizona
Restoration thinning and burning treatments in southwestern ponderosa pine (Pinus ponderosa) forests are designed to both reduce the risk of wildfire and restore ecosystem functions and structure, including maintaining or reestablishing habitat for wildlife populations. However, we found limited quantitative data regarding wildlife responses to restoration treatments and changes in forest structure because most previous studies were conducted at small temporal and spatial scales, and they generally focused on bird species (Kalies et al. 2010). In addition, although habitat components, such as Gambel oak (Quercus gambelii), large-diameter trees, snags and downwood, are thought to be important to wildlife, there is debate about treatment targets on the landscape (Abella et al. 2006, Noss et al. 2006). In this ERI Working Papers , we present the results of a study that assessed small mammal responses to treatments--responses previously unexamined at the community level or at large temporal and spatial scales in southwestern ponderosa pine forests
Population genetic patterns among social groups of the endangered Central American spider monkey (Ateles geoffroyi) in a human-dominated landscape
Spider monkeys (Genus: Ateles) are a widespread Neotropical primate with a highly plastic socioecological strategy. However, the Central American species, Ateles geoffroyi, was recently re-listed as endangered due to the accelerated loss of forest across the subcontinent. There is inconsistent evidence that spider monkey populations could persist when actively protected, but their long-term viability in unprotected, human-dominated landscapes is not known. We analyzed noninvasive genetic samples from 185 individuals in 14 putative social groups on the Rivas Isthmus in southwestern Nicaragua. We found evidence of weak but significant genetic structure in the mitochondrial control region and in eight nuclear microsatellite loci plus negative spatial autocorrelation in Fst and kinship. The overall pattern suggests strong localized mating and at least historical female-biased dispersal, as is expected for this species. Heterozygosity was significantly lower than expected under random mating and lower than that found in other spider monkey populations, possibly reflecting a recent decline in genetic diversity and a threat from inbreeding. We conclude that despite a long history of human disturbance on this landscape, spider monkeys were until recently successful at maintaining gene flow. We consider the recent decline to be further indication of accelerated anthropogenic disturbance, but also of an opportunity to conserve native biodiversity. Spider monkeys are one of many wildlife species in Central America that is threatened by land cover change, and an apt example of how landscape-scale conservation planning could be used to ensure long-term persistence
Systematic Review – Final: How do thinning and burning treatments in southwestern conifer forests in the United States affect wildlife density and population performance?
The aim of this review is to examine whether thinning and burning treatments in conifer forests in the southwestern United States affect wildlife distribution, abundance, and population performance
Bats use live fences to move between tropical dry forest remnants
Linear features can benefit wildlife by assisting animal movement. We captured bats along barbedâ wire and liveâ tree fences connecting tropical dry forest patches in Nicaragua. Bat species richness and captures were higher along live fences but we noted differences in sex ratios, richness, and species composition compared to surrounding natural forests.Abstract in Spanish is available with online onlyResumenLa degradación del hábitat y fragmentación del bosque son amenazas para la biodiversidad a nivel mundial. Estructuras lineales pueden beneficiar la vida silvestre, al asistir movimiento de animales entre parches de hábitat. Cercas definen cultivos o áreas de pastoreo usando alambre de púas y postes de madera, pero las cercas vivas reemplazan los postes de madera con árboles, creando corredores que animales pueden usar para moverse a través del paisaje fragmentado. Nosotros capturamos 279 murciélagos de 17 especies a lo largo de 27 sitios pareados de cercas tradicionales y cercas vivas conectando bosque seco tropical mesoamericano en el sudeste de Nicaragua. Riqueza y capturas de murciélagos fueron dos y cuatro veces mas altas en cercas vivas. Sin embargo, diferencias en proporciones de sexo, riqueza y composición de las capturas indican que las cercas vivas no proveen los mismos beneficios de conectividad para todas las especies.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153733/1/btp12751_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153733/2/btp12751.pd
Pleistocene/Holocene Cave Fossils From Grand Canyon National Park: Ice Age (Pleistocene) Flora, Fauna, Environments, and Climate of the Grand Canyon, Arizona
The Colorado Plateau is a distinct physiographic province in western North America covering an area of roughly 337,000 km2 (130,115 mi2) across parts of Arizona, Colorado, New Mexico, and Utah. Elevations range from about 360 m (1,180 ft) in the overall Grand Canyon (GC; which includes the Grand Canyon National Park, GRCA) river corridor to an average at the eastern South Rim of 2,072 m (6,800 ft) to 3,850 m (12,630 ft) on the nearby San Francisco Peaks at Flagstaff, Arizona, with an average elevation of 1,525 m (5,000 ft). The Colorado River of Grand Canyon is located along the southwestern portion of the Colorado Plateau in Arizona and is renowned for its dramatic display of geomorphic effects created by fluvial incision and its unique dry-preservation of fossils from the Ice Age (late Pleistocene and Holocene [Quaternary]; most recent 2.58 million years). Although there were at least 22 glacial-interglacial cycles during the Ice Age, this discussion is limited to the most recent episode (called the Wisconsinan Glaciation), which includes the transition to the modern climate (latest Pleistocene and Holocene; the most recent 50,000 years of geologic history)
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College of Forestry Integrated Research Project : ecological and socioeconomic responses to alternative silvicultural treatments
The College of Forestry Integrated Research Project (CFIRP) is an on-going experiment in the eastern Coast Range foothills of western Oregon. Started in 1989, a team of scientists, resource managers, and students at Oregon State University designed and implemented silvicultural alternatives to clearcutting. These silvicultural practices aimed to create and retain features of mature and old-growth Douglas- fir (Pseudotsuga menziesii) forests while also producing timber. Fine-, moderate-, and large-scale natural disturbance patterns served as the basis for prescriptions. The study includes replicates of three silvicultural treatments (n = 27 stands) wherein 33% to 95% of the timber volume was removed, three non-replicated demonstration treatments wherein 33% of timber volume was removed in variable sized and shaped patches, and untreated controls (n = 3 stands). Additionally, clumped or randomly distributed snags were created from green trees in each stand. In this book, CFIRP scientists describe harvest challenges and economics; short-term (10-yr) responses of vegetation, wildlife, and humans to silvicultural treatments; and additional studies conducted using CFIRP study sites. A synopsis of past and present research and management directions also is included. Work continues on CFIRP today, and data collected from previous studies are available to other researchers. By comparing characteristics of forests managed under different silvicultural systems, we will be better able to assess their potential economic, social, and ecological contributions to managed forest landscapes
international Epidemiology of Carbapenemase-Producing Escherichia Coli
BACKGROUND: Carbapenemase-producing (CP) Escherichia coli (CP-Ec) are a global public health threat. We aimed to describe the clinical and molecular epidemiology and outcomes of patients from several countries with CP-Ec isolates obtained from a prospective cohort.
METHODS: Patients with CP-Ec were enrolled from 26 hospitals in 6 countries. Clinical data were collected, and isolates underwent whole-genome sequencing. Clinical and molecular features and outcomes associated with isolates with or without metallo-β-lactamases (MBLs) were compared. The primary outcome was desirability of outcome ranking (DOOR) at 30 days after the index culture.
RESULTS: Of the 114 CP-Ec isolates in Consortium on resistance against carbapenems in Klebsiella and other Enterobacterales-2 (CRACKLE-2), 49 harbored an MBL, most commonly blaNDM-5 (38/49, 78%). Strong regional variations were noted with MBL-Ec predominantly found among patients in China (23/49). Clinically, MBL-Ec were more often from urine sources (49% vs 29%), less often met criteria for infection (39% vs 58%, P = .04), and had lower acuity of illness when compared with non-MBL-Ec. Among patients with infection, the probability of a better DOOR outcome for a randomly selected patient with MBL-Ec as compared with non-MBL-Ec was 62% (95% CI: 48.2-74.3%). Among infected patients, non-MBL-Ec had increased 30-day (26% vs 0%; P = .02) and 90-day (39% vs 0%; P = .001) mortality compared with MBL-Ec.
CONCLUSIONS: Emergence of CP-Ec was observed with important geographic variations. Bacterial characteristics, clinical presentations, and outcomes differed between MBL-Ec and non-MBL-Ec. Mortality was higher among non-MBL isolates, which were more frequently isolated from blood, but these findings may be confounded by regional variations
Rucaparib maintenance treatment for recurrent ovarian carcinoma after response to platinum therapy (ARIEL3): a randomised, double-blind, placebo-controlled, phase 3 trial
Background:
Rucaparib, a poly(ADP-ribose) polymerase inhibitor, has anticancer activity in recurrent ovarian carcinoma harbouring a BRCA mutation or high percentage of genome-wide loss of heterozygosity. In this trial we assessed rucaparib versus placebo after response to second-line or later platinum-based chemotherapy in patients with high-grade, recurrent, platinum-sensitive ovarian carcinoma.
Methods:
In this randomised, double-blind, placebo-controlled, phase 3 trial, we recruited patients from 87 hospitals and cancer centres across 11 countries. Eligible patients were aged 18 years or older, had a platinum-sensitive, high-grade serous or endometrioid ovarian, primary peritoneal, or fallopian tube carcinoma, had received at least two previous platinum-based chemotherapy regimens, had achieved complete or partial response to their last platinum-based regimen, had a cancer antigen 125 concentration of less than the upper limit of normal, had a performance status of 0–1, and had adequate organ function. Patients were ineligible if they had symptomatic or untreated central nervous system metastases, had received anticancer therapy 14 days or fewer before starting the study, or had received previous treatment with a poly(ADP-ribose) polymerase inhibitor. We randomly allocated patients 2:1 to receive oral rucaparib 600 mg twice daily or placebo in 28 day cycles using a computer-generated sequence (block size of six, stratified by homologous recombination repair gene mutation status, progression-free interval after the penultimate platinum-based regimen, and best response to the most recent platinum-based regimen). Patients, investigators, site staff, assessors, and the funder were masked to assignments. The primary outcome was investigator-assessed progression-free survival evaluated with use of an ordered step-down procedure for three nested cohorts: patients with BRCA mutations (carcinoma associated with deleterious germline or somatic BRCA mutations), patients with homologous recombination deficiencies (BRCA mutant or BRCA wild-type and high loss of heterozygosity), and the intention-to-treat population, assessed at screening and every 12 weeks thereafter. This trial is registered with ClinicalTrials.gov, number NCT01968213; enrolment is complete.
Findings:
Between April 7, 2014, and July 19, 2016, we randomly allocated 564 patients: 375 (66%) to rucaparib and 189 (34%) to placebo. Median progression-free survival in patients with a BRCA-mutant carcinoma was 16·6 months (95% CI 13·4–22·9; 130 [35%] patients) in the rucaparib group versus 5·4 months (3·4–6·7; 66 [35%] patients) in the placebo group (hazard ratio 0·23 [95% CI 0·16–0·34]; p<0·0001). In patients with a homologous recombination deficient carcinoma (236 [63%] vs 118 [62%]), it was 13·6 months (10·9–16·2) versus 5·4 months (5·1–5·6; 0·32 [0·24–0·42]; p<0·0001). In the intention-to-treat population, it was 10·8 months (8·3–11·4) versus 5·4 months (5·3–5·5; 0·36 [0·30–0·45]; p<0·0001). Treatment-emergent adverse events of grade 3 or higher in the safety population (372 [99%] patients in the rucaparib group vs 189 [100%] in the placebo group) were reported in 209 (56%) patients in the rucaparib group versus 28 (15%) in the placebo group, the most common of which were anaemia or decreased haemoglobin concentration (70 [19%] vs one [1%]) and increased alanine or aspartate aminotransferase concentration (39 [10%] vs none).
Interpretation:
Across all primary analysis groups, rucaparib significantly improved progression-free survival in patients with platinum-sensitive ovarian cancer who had achieved a response to platinum-based chemotherapy. ARIEL3 provides further evidence that use of a poly(ADP-ribose) polymerase inhibitor in the maintenance treatment setting versus placebo could be considered a new standard of care for women with platinum-sensitive ovarian cancer following a complete or partial response to second-line or later platinum-based chemotherapy.
Funding:
Clovis Oncology
Promoting help-seeking in response to symptoms amongst primary care patients at high risk of lung cancer: a mixed method study
Background: Lung cancer symptoms are vague and difficult to detect. Interventions are needed to promote early diagnosis, however health services are already pressurised. This study explored symptomology and help-seeking behaviours of primary care patients at ‘high-risk’ of lung cancer (≥50 years old, recent smoking history), to inform targeted interventions.
Methods: Mixed method study with patients at eight general practitioner (GP) practices across south England. Study incorporated: postal symptom questionnaire; clinical records review of participant consultation behaviour 12 months pre- and post-questionnaire; qualitative participant interviews (n = 38) with a purposive sample.
Results: A small, clinically relevant group (n = 61/908, 6.7%) of primary care patients was identified who, despite reporting potential symptoms of lung cancer in questionnaires, had not consulted a GP ≥12 months. Of nine symptoms associated with lung cancer, 53.4% (629/1172) of total respondents reported ≥1, and 35% (411/1172) reported ≥2. Most participants (77.3%, n = 686/908) had comorbid conditions; 47.8%, (n = 414/908) associated with chest and respiratory symptoms. Participant consulting behaviour significantly increased in the 3-month period following questionnaire completion compared with the previous 3-month period (p = .002), indicating questionnaires impacted upon consulting behaviour. Symptomatic non-consulters were predominantly younger, employed, with higher multiple deprivation scores than their GP practice mean. Of symptomatic non-consulters, 30% (18/61) consulted ≤1 month post-questionnaire, with comorbidities subsequently diagnosed for five participants. Interviews (n = 39) indicated three overarching differences between the views of consulting and non-consulting participants: concern over wasting their own as well as GP time; high tolerance threshold for symptoms; a greater tendency to self-manage symptoms.
Conclusions: This first study to examine symptoms and consulting behaviour amongst a primary care population at ‘high- risk’ of lung cancer, found symptomatic patients who rarely consult GPs, might respond to a targeted symptom elicitation intervention. Such GP-based interventions may promote early diagnosis of lung cancer or other comorbidities, without burdening already pressurised services
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