Ivory poaching, sociality, and the role of behavior in conservation

Includes bibliographical references.2016 Fall.The potential of animal behavior to contribute to conservation biology has been acknowledged for decades, but empirical work to realize this potential has been surprisingly slow (Sutherland 1998; Caro 2007; Angeloni et al. 2008; Berger-Tal et al. 2015). Behavior that reliably conveys the response of populations to human threats may be particularly useful in assessing population status and recovery potential as it can be measured over relatively short time periods. African elephants (Loxodonta africana) rely heavily on behavioral decisions and are highly dependent on complex social processes that revolve around older animals (Douglas-Hamilton 1972; Moss 1988; Wittemyer et al. 2005b). Within the last decade poaching of elephants for their ivory has increased to meet rising demand on international markets (Maisels et al. 2013; Wittemyer et al. 2014), which has disproportionately been targeted toward older elephants for their larger tusks (Wittemyer et al. 2013; Chiyo et al. 2015). In this dissertation I analyze behavior in the context of a well-studied population of African elephants in northern Kenya under illegal killing pressure, with emphasis on social behavior. I describe baseline levels of sociality among adult male elephants prior to the intensification of poaching, compare hierarchical social network structure of female elephants before and during poaching, investigate fine-scale social strategies among young females following family mortalities, assess the utility of a flight metric as a behavioral indicator of harvest pressure, and examine the overlap in area use of two adjacent subpopulations. This work contributes to the growing literature on conservation behavioral methods and advances understanding of sociality in this threatened species

Exact Computation of Influence Spread by Binary Decision Diagrams

Evaluating influence spread in social networks is a fundamental procedure to estimate the word-of-mouth effect in viral marketing. There are enormous studies about this topic; however, under the standard stochastic cascade models, the exact computation of influence spread is known to be #P-hard. Thus, the existing studies have used Monte-Carlo simulation-based approximations to avoid exact computation. We propose the first algorithm to compute influence spread exactly under the independent cascade model. The algorithm first constructs binary decision diagrams (BDDs) for all possible realizations of influence spread, then computes influence spread by dynamic programming on the constructed BDDs. To construct the BDDs efficiently, we designed a new frontier-based search-type procedure. The constructed BDDs can also be used to solve other influence-spread related problems, such as random sampling without rejection, conditional influence spread evaluation, dynamic probability update, and gradient computation for probability optimization problems. We conducted computational experiments to evaluate the proposed algorithm. The algorithm successfully computed influence spread on real-world networks with a hundred edges in a reasonable time, which is quite impossible by the naive algorithm. We also conducted an experiment to evaluate the accuracy of the Monte-Carlo simulation-based approximation by comparing exact influence spread obtained by the proposed algorithm.Comment: WWW'1

Peroxisomes in intestinal and gallbladder epithelial cells of the stickleback, Gasterosteus aculeatus L. (Teleostei)

The occurrence of microbodies in the epithelial cells of the intestine and gallbladder of the stickleback, Gasterosteus aculeatus L., is described. In the intestine the organelles are predominantly located in the apical and perinuclear zone of the cells and may contain small crystalline cores. In gallbladder epithelial cells the microbodies are distributed randomly. The latter organdies are characterized by the presence of large crystalloids. Cytochemical and biochemical experiments show that catalase and D-amino acid oxidase are main matrix components of the microbodies in both the intestinal and gallbladder epithelia. These organelles therefore are considered peroxisomes. In addition, in intestinal mucosa but not in gallbladder epithelium a low activity of palmitoyl CoA oxidase was detected biochemically. Urate oxidase and L-α hydroxy acid oxidase activities could not be demonstrated.

Use of marginal organs in kidney transplantation for marginal recipients: too close to the margins of safety?

<p>Abstract</p> <p>Objective</p> <p>Due to organ shortage, average waiting time for a kidney in Germany is about 4 years after start of dialysis. Number of kidney grafts recovered can only be maintained by accepting older and expanded criteria donors. The aim of this study was to analyse the impact of donor and recipient risk on kidney long-term function.</p> <p>Methods</p> <p>All deceased kidney transplantations were considered. We retrospectively studied 332 patients between 2002 and 2006; divided in 4 groups reflecting donor and recipient risk.</p> <p>Results</p> <p>Non-marginal recipients were less likely to receive a marginal organ (69 of 207, 33%) as compared to marginal recipients, of whom two-thirds received a marginal organ (p < 0.0001). Graft function significantly differed between the groups, but detrimental effect of marginal recipient status on eGFR after 12 months (-6 ml/min/1.73 qm, 95% CI -2 to -9) was clearly smaller than the effect of marginal donor status (-10 ml/min/1.73 qm, 95% CI -7 to -14).</p> <p>Conclusions</p> <p>As we were able to show expanded criteria donor has a far bigger effect on long-term graft function than the "extra risk" recipient. Although there have been attempts to define groups of recipients who should be offered ECD kidneys primarily the discussion is still ongoing.</p

Bezafibrate treatment is associated with a reduced rate of re-hospitalization in smokers after acute coronary syndrome

Background: Significantly increased rate of hospitalizations in current smokers is a major smoking-related problem which is associated with a heavy economic burden, whereas car­diovascular disease accounted for nearly half of hospitalizations. The effect of bezafibrate on the rate of re-hospitalization in smokers already treated with statin immediately post-acute coronary syndrome (ACS) is unknown. The aim of this study was to investigate 30-day rate of re-hospitalization in current smokers participating in the ACS Israeli Surveys (ACSIS) and who were treated on discharge with a bezafibrate/statin combination vs. statin alone. Methods: The study population comprised 3392 patients with confirmed current smoking status from the ACSIS 2000, 2002, 2004, 2006, 2008 and 2010 enrollment waves who were alive on discharge and received statin. Of these, 3189 (94%) were discharged with statin alone, 203 (6%) with a combination of a statin and bezafibrate. Results: Thirty-day re-hospitalization rate was significantly lower in patients from the com­bination group than in their counterparts from the statin monotherapy group: 12.8% vs. 19%, p = 0.028. Multivariable analysis identified the combined bezafibrate/statin treatment as an independent predictor of reduced risk of 30-day re-hospitalization rate with odds ratio (OR) 0.53 (95% confidence interval [CI] 0.31–0.91), and it corresponded to 47% risk reduction. Other significant variables in our model associated with independent risk of 30-day re-hospi­talization rate during the follow-up were female gender (OR 1.43, CI 1.05–1.95, p = 0.03) and age &gt; 65 years (OR 1.49, CI 1.13–1.95, p = 0.004). Conclusions: Adding bezafibrate to statin in smokers was associated with a significantly reduced 30-day rate of re-hospitalization after ACS.

Zinc for the prevention or treatment of acute viral respiratory tract infections in adults : a rapid systematic review and meta-analysis of randomised controlled trials

Objective To evaluate the benefits and risks of zinc formulations compared with controls for prevention or treatment of acute viral respiratory tract infections (RTIs) in adults. Method Seventeen English and Chinese databases were searched in April/May 2020 for randomised controlled trials (RCTs), and from April/May 2020 to August 2020 for SARS-CoV-2 RCTs. Cochrane rapid review methods were applied. Quality appraisals used the Risk of Bias 2.0 and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Results Twenty-eight RCTs with 5446 participants were identified. None were specific to SARS-CoV-2. Compared with placebo, oral or intranasal zinc prevented 5 RTIs per 100 person-months (95% CI 1 to 8, numbers needed to treat (NNT)=20, moderate-certainty/quality). Sublingual zinc did not prevent clinical colds following human rhinovirus inoculations (relative risk, RR 0.96, 95% CI 0.77 to 1.21, moderate-certainty/quality). On average, symptoms resolved 2 days earlier with sublingual or intranasal zinc compared with placebo (95% CI 0.61 to 3.50, very low-certainty/quality) and 19 more adults per 100 were likely to remain symptomatic on day 7 without zinc (95% CI 2 to 38, NNT=5, low-certainty/quality). There were clinically significant reductions in day 3 symptom severity scores (mean difference, MD-1.20 points, 95% CI-0.66 to-1.74, low-certainty/quality), but not average daily symptom severity scores (standardised MD-0.15, 95% CI-0.43 to 0.13, low-certainty/quality). Non-serious adverse events (AEs) (eg, nausea, mouth/nasal irritation) were higher (RR 1.41, 95% CI 1.17 to 1.69, NNHarm=7, moderate-certainty/quality). Compared with active controls, there were no differences in illness duration or AEs (low-certainty/quality). No serious AEs were reported in the 25 RCTs that monitored them (low-certainty/quality). Conclusions In adult populations unlikely to be zinc deficient, there was some evidence suggesting zinc might prevent RTIs symptoms and shorten duration. Non-serious AEs may limit tolerability for some. The comparative efficacy/effectiveness of different zinc formulations and doses were unclear. The GRADE-certainty/quality of the evidence was limited by a high risk of bias, small sample sizes and/or heterogeneity. Further research, including SARS-CoV-2 clinical trials is warranted

Does the lipid-lowering peroxisome proliferator-activated receptors ligand bezafibrate prevent colon cancer in patients with coronary artery disease?

<p>Abstract</p> <p>Background</p> <p>Epidemiologic studies have suggested that hypertriglyceridemia and insulin resistance are related to the development of colon cancer. Nuclear peroxisome proliferator-activated receptors (PPAR), which play a central role in lipid and glucose metabolism, had been hypothesized as being involved in colon cancerogenesis. In animal studies the lipid-lowering PPAR ligand bezafibrate suppressed colonic tumors. However, the effect of bezafibrate on colon cancer development in humans is unknown. Therefore, we proposed to investigate a possible preventive effect of bezafibrate on the development of colon cancer in patients with coronary artery disease during a 6-year follow-up.</p> <p>Methods</p> <p>Our population included 3011 patients without any cancer diagnosis who were enrolled in the randomized, double blind Bezafibrate Infarction Prevention (BIP) Study. The patients received either 400 mg of bezafibrate retard (1506 patients) or placebo (1505 patients) once a day. Cancer incidence data were obtained by matching a subject's identification numbers with the National Cancer Registry. Each matched record was checked for correct identification.</p> <p>Results</p> <p>Development of new cancer (all types) was recorded in 177 patients: in 79 (5.25%) patients from the bezafibrate group vs. 98 (6.51%) from the placebo group. Development of colon cancer was recorded in 25 patients: in 8 (0.53%) patients from the bezafibrate group vs. 17 (1.13%) from the placebo group, (Fisher's exact test: one side p = 0.05; two side p = 0.07).</p> <p>A difference in the incidence of cancer was only detectable after a 4 year lag and progressively increased with continued follow-up. On multivariable analysis the colon cancer risk in patients who received bezafibrate tended to be lower with a hazard ratio of 0.47 and 95% confidence interval 0.2–1.1.</p> <p>Conclusion</p> <p>Our data, derived from patients with coronary artery disease, support the hypothesis regarding a possible preventive effect of bezafibrate on the development of colon cancer.</p

From Single-Visit to Multi-Visit Image-Based Models: Single-Visit Models are Enough to Predict Obstructive Hydronephrosis

Previous work has shown the potential of deep learning to predict renal obstruction using kidney ultrasound images. However, these image-based classifiers have been trained with the goal of single-visit inference in mind. We compare methods from video action recognition (i.e. convolutional pooling, LSTM, TSM) to adapt single-visit convolutional models to handle multiple visit inference. We demonstrate that incorporating images from a patient's past hospital visits provides only a small benefit for the prediction of obstructive hydronephrosis. Therefore, inclusion of prior ultrasounds is beneficial, but prediction based on the latest ultrasound is sufficient for patient risk stratification.Comment: Paper accepted to SIPAIM 2022 (in Valparaiso, Chile