Predation Risk and Vegetation Effects on Avian Diversity, Species Turnover, Reproduction, and Fitness

Vegetation is the habitat that underlies animal distributions. Yet mechanisms by which dynamic changes in vegetation affect animal fitness, distributions, and communities remain unclear. For example, animal richness and species composition often change with decreased forest structural complexity associated with anthropogenic disturbance, but differences in latitude and vegetation effects on reproductive success may influence species responses to vegetation changes. My global meta-analysis of logging effects on bird communities revealed substantial species loss in tropical but not temperate forests. This suggests tropical birds exhibit greater habitat specialization than their temperate relatives. My meta-analysis also suggested that changes in reproductive success can influence how animals distribute themselves in response to vegetation change. I examined this hypothesis with an in-depth observational study and landscape-scale experiment. Habitat use and nest predation rates were examined for 16 bird species that breeding along a deciduous to coniferous vegetation gradient and with experimental conifer removal from aspen stands. For most bird species, decreasing abundance was associated with increasing predation risk along both natural and experimentally modified vegetation gradients. This landscape-scale approach strongly supports the idea that vegetation-mediated effects of predation risk are associated with animal distributions and species turnover. While direct predation mortality clearly has effects on animal population dynamics, the risk of predation alone may have equally large effects on reproduction and, ultimately, fitness. Yet the severity and generality of such demographic ‘costs of fear’ is unknown across species. I tested phenotypic responses to risk and associated demographic costs for 10 songbird species breeding along natural nest predation gradients and by experimentally increasing risk for four species. Parents decreased offspring development periods, reducing time-dependent nest mortality with natural and experimental increases in risk. Reproductive output from nests in the absence of direct predation generally declined along risk gradients, but the severity of this cost varied across species. Ultimately, demographic costs of fear reduced fitness across bird species, but not as strongly as direct predation mortality. These landscape and experimental tests suggest that vegetation affects the perceived risk of predation, and thereby strongly influences avian behaviors, fitness, distributions, and community assembly

A Study of the Relationship Between Indentation Creep and Uniaxial Creep

The purpose of this work is to further the scientific understanding of the relationship between indentation creep and uniaxial creep. The data for this study was obtained by conducting both indentation and uniaxial creep experiments on amorphous selenium. Experiments were designed to collect data over a wide range of creep rates. Specific temperatures were chosen to collect creep data above and below the glass transition temperature of 31°C. The indentation and uniaxial compression data was used to accomplish several objectives. The first objective was to test the ability of the Oliver-Pharr stiffness equation to predict contact area. The current contact area calculation technique relies on elastic recovery to account for sink-in and can not account for pile-up. It is shown that if the modulus of the material is known as a function of temperature, the Oliver-Pharr stiffness equation can generally predict the contact area within 10 percent of areas measured from optical and interference photomicrographs. This method accurately predicts areas for predominately plastic indents that display almost no elastic recovery where photomicrographs show that the indent has experienced considerable sink-in. The second objective was to analyze Bower et. al’s prediction of the sink-in/pile- up parameter, c, as a function of the creep exponent, n. The parameter c is defined as the ratio of indent contact depth to indent total depth. The calculations of the parameter c from indent profiles are within 10 percent of Bower’s model. Bower over predicts between 15 and 30 percent when c is calculated from measured areas. The third and primary objective of this study was to calculate the relationship between the uniaxial creep parameter, A, and the indentation creep parameter, B. The A/B ratio was calculated for both nominal mean pressure, that does not account for sink- in and pile up, and actual mean pressure. The A/B ratio calculated by the nominal mean pressure method, when computed with 2% plastic strain compression stresses, is consistent with Bower et. al’s prediction. The A/B ratio calculated with the actual mean pressure method, when computed with 2% plastic strain compression stresses, is approximately 100 percent higher then the prediction by Bower

Characterizing and prognosticating chronic lymphocytic leukemia in the elderly: prospective evaluation on 455 patients treated in the United States.

BACKGROUND: Median age at diagnosis of patients with chronic lymphocytic leukemia (CLL) is \u3e 70 years. However, the majority of clinical trials do not reflect the demographics of CLL patients treated in the community. We examined treatment patterns, outcomes, and disease-related mortality in patients ≥ 75 years with CLL (E-CLL) in a real-world setting. METHODS: The Connect® CLL registry is a multicenter, prospective observational cohort study, which enrolled 1494 adult patients between 2010-2014, at 199 US sites. Patients with CLL were enrolled within 2 months of initiating first line of therapy (LOT1) or a subsequent LOT (LOT ≥ 2). Kaplan-Meier methods were used to evaluate overall survival. CLL- and infection-related mortality were assessed using cumulative incidence functions (CIF) and cause-specific hazards. Logistic regression was used to develop a classification model. RESULTS: A total of 455 E-CLL patients were enrolled; 259 were enrolled in LOT1 and 196 in LOT ≥ 2. E-CLL patients were more likely to receive rituximab monotherapy (19.3 vs. 8.6%; p \u3c 0.0001) and chemotherapy-alone regimens (p \u3c 0.0001) than younger patients. Overall and complete responses were lower in E-CLL patients than younger patients when given similar regimens. With a median follow-up of 3 years, CLL-related deaths were higher in E-CLL patients than younger patients in LOT1 (12.6 vs. 5.1% p = 0.0005) and LOT ≥ 2 (31.3 vs. 21.5%; p = 0.0277). Infection-related deaths were also higher in E-CLL patients than younger patients in LOT1 (7.4 vs. 2.7%; p = 0.0033) and in LOT ≥ 2 (16.2 vs. 11.2%; p = 0.0786). A prognostic score for E-CLL patients was developed: time from diagnosis to treatment \u3c 3 months, enrollment therapy other than bendamustine/rituximab, and anemia, identified patients at higher risk of inferior survival. Furthermore, higher-risk patients experienced an increased risk of CLL- or infection-related death (30.6 vs 10.3%; p = 0.0006). CONCLUSION: CLL- and infection-related mortality are higher in CLL patients aged ≥ 75 years than younger patients, underscoring the urgent need for alternative treatment strategies for these understudied patients. TRIAL REGISTRATION: The Connect CLL registry was registered at clinicaltrials.gov: NCT01081015 on March 4, 2010

Real-world clinical experience in the Connect® chronic lymphocytic leukaemia registry: a prospective cohort study of 1494 patients across 199 US centres.

The clinical course of chronic lymphocytic leukaemia (CLL) is heterogeneous, and treatment options vary considerably. The Connect® CLL registry is a multicentre, prospective observational cohort study that provides a real-world perspective on the management of, and outcomes for, patients with CLL. Between 2010 and 2014, 1494 patients with CLL and that initiated therapy, were enrolled from 199 centres throughout the USA (179 community-, 17 academic-, and 3 government-based centres). Patients were grouped by line of therapy at enrolment (LOT). We describe the clinical and demographic characteristics of, and practice patterns for, patients with CLL enrolled in this treatment registry, providing patient-level observational data that represent real-world experiences in the USA. Fluorescence in situ hybridization (FISH) analyses were performed on 49·3% of patients at enrolment. The most common genetic abnormalities detected by FISH were del(13q) and trisomy 12 (45·7% and 20·8%, respectively). Differences in disease characteristics and comorbidities were observed between patients enrolled in LOT1 and combined LOT2/≥3 cohorts. Important trends observed include the infrequent use of genetic prognostic testing, and differences in patient characteristics for patients receiving chemoimmunotherapy combinations. These data represent experiences of patients with CLL in the USA, which may inform treatment decisions in everyday practice

Evidence-based opportunities for out-scaling climate-smart agriculture in East Africa

Climate-smart agriculture (CSA) is being widely promoted as a solution for food insecurity and climate change adaptation in food systems of sub-Saharan Africa, while simultaneously reducing the rate of greenhouse gas emissions. Governments throughout Africa are writing policies and programs to promote CSA practices despite uncertainty about the ability for practices to meet the triple CSA objectives of CSA. We conducted a systematic review of 175 peer-reviewed and grey literature studies, to gauge the impact of over seventy potential CSA practices on CSA outcomes in Tanzania and Uganda. Using a total of 6,342 observations, we found that practice impacts were highly context (i.e. farming system and location) specific. Nevertheless, practice effect across CSA outcomes generally agreed in direction. While our results suggest that CSA is indeed possible, lack of mitigation data precludes a more conclusive statement. Furthermore, the inclusion of potential adoption rates changes the potential of CSA practices to achieve benefits at scale. Given the uncertainty and variable impacts of practices across regions and outcomes, it is critical for decision makers to prioritize practices based on their desired outcomes and local context

What is the evidence-base for climate-smart agriculture in Tanzania?

Evidence exists to support CSA programming on the most widely cultivated crops (e.g. maize), and most common agricultural practices (e.g. fertilizer addition) in Tanzania. However, products and places central to rural livelihoods such as livestock, coastal drylands, and humid regions near Lake Victoria are understudied. Data on how CSA changes agricultural productivity is widely available (77% of the data), while 20% of the data is related to resilience indicators, and only 3% deals with greenhouse gas mitigation outcomes. Practitioners should draw on this rich evidence base for CSA in Tanzania, while also prioritizing the generation of evidence for understudied products, agroecologies, and practices

Treatment of fecal impaction in children using combined polyethylene glycol and sodium picosulphate

Background and Aim: Polyethylene glycol (PEG) is the gold standard for fecal disimpaction in constipation. A regimen of PEG combined with the stimulant laxative sodium picosulphate (SPS) produced fecal disimpaction in chronically constipated children in the community, but it is unknown if it is effective for more severe constipation. To determine the stool output and effect of a combined PEG and SPS regimen on fecaloma in children with severe constipation and impaction. Methods: Children with symptoms for a duration of >= 2 years, a palpable fecaloma, and enlarged rectum on X-ray (rectal: pelvic ratio > 0.6) were recruited from a tertiary hospital. Daily diaries recorded laxative dose, stool frequency, volume, and consistency (Bristol stool scale, BSS). Abdominal X-rays were taken on day 1 and day 8, and stool loading was assessed using the Leech score. Laxative doses were based on the child's age. The dose of PEG with electrolytes taken was 2-8 sachets (14.7 g/sachet) on days 1-2, reducing to 2-6 sachets on day 3. The SPS dose was 15-20 drops on days 2-3. Results: Eighty-nine children (4-18 years) produced a large volume of soft stool (median/inter-quartile-range: 2.2/1.6-3.1 L) over 7 days. Stool volume on X-rays decreased significantly in the colon (P <0.001). Fecalomas resolved in 40 of 89 children, while 49 needed a second high dose. Rectal: pelvic ratios did not change. Conclusions: A combined high dose of PEG and SPS on days 1 and 2 was effective in removing the fecaloma in half of the children. Administering high doses for a longer period should be tested to provide outpatient disimpaction for severe fecalomas. Rectums remained flaccid after emptying

Azimuthal single spin asymmetries in SIDIS in the light of chiral symmetry breaking

An attempt is made to understand the z-dependence of the azimuthal single spin asymmetries observed by the HERMES collaboration in terms of chiral models based on effective quark and Goldstone boson degrees of freedom. The effects of respectively neglecting and considering Gaussian intrinsic parton transverse momenta and the Sivers effect are explored. Predictions for the transverse target polarization experiment at HERMES are presented.Comment: 14 pages, 18 figure

Prioritizing Tanzania’s agricultural development policy to build smallholder climate resilience. Final report for the Bill & Melinda Gates Foundation Grand Challenges Explorations 22: Risk-explicit and Evidence-based Policy Prioritization (REAP)

Faced with myriad options, Sub-Saharan Africa policy makers struggle to prioritize actions. Commonly used modeling approaches perform poorly in data scare conditions or focus intently on tools at hand. Policies, by consequence, report ‘wish lists’, making them a challenge to implement given resource constraints. Here, we evaluate the potential of using an alternative approach, Bayesian Networks (BNs), to prioritize agricultural policy actions, specifically modeling seven ‘Investment Areas’ listed in Tanzania’s Agriculture Sector Development Programme II