An Approach to Ecosystem-Based Fishery Management

Marine scientists and policymakers are encouraging ecosystem-based fishery management (EBFM), but there is limited guidance on how to operationalize the concept. We adapt financial portfolio theory as a method for EBFM that accounts for species interdependencies, uncertainty, and sustainability constraints. Illustrating our method with routinely collected data available from the Chesapeake Bay, we demonstrate the gains from taking into account species variances and covariances in setting species total allowable catches. We find over the period from 1962–2003 that managers could have increased the revenues from fishing and reduced the variance by employing ecosystem frontiers in setting catch levels.ecosystem-based fishery management, portfolio, trophic modeling, precaution

Association between depression and concurrent Type 2 diabetes outcomes varies by diabetes regimen

Aims  Although depression has weak associations with several Type 2 diabetes mellitus (DM) outcomes, it is possible that these associations are concentrated within certain patient subgroups that are more vulnerable to their effects. This study tested the hypothesis that depression is related to glycaemic control and diabetes-related quality of life (DQOL) in patients who are prescribed injected insulin, but not those on oral glucose-lowering agents alone. Methods  Participants (103 on insulin, 155 on oral glucose-lowering agents alone) with Type 2 DM were recruited from a large US healthcare system and underwent assessment of glycaemic control (glycated haemoglobin; HbA 1c ), medication adherence and diabetes self-care behaviours, DQOL and depression (none, mild, moderate/severe). Results  There was a significant regimen × depression interaction on HbA 1c ( P  = 0.002), such that depression was associated with HbA 1c in patients using insulin (β = 0.35, P  < 0.001) but not in patients using oral agents alone (β = –0.08, P  = NS). There was a similar interaction when quality of life was analysed as an outcome ( P  = 0.002). Neither effect was mediated by regimen adherence. Conclusions  The generally weak association between depression and glycaemic control is concentrated among patients who are prescribed insulin. Similarly, the association between depression and illness quality of life is strongest in patients prescribed insulin. Because this is not attributable to depression-related adherence problems, psychophysiological mechanisms unique to this group ought to be carefully investigated. Clinicians might be especially vigilant for depression in Type 2 DM patients who use insulin and consider its potential impact upon their illness course. Diabet. Med. 25, 1324–1329 (2008)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73538/1/j.1464-5491.2008.02590.x.pd

Localization Recall Precision (LRP): A New Performance Metric for Object Detection

Average precision (AP), the area under the recall-precision (RP) curve, is the standard performance measure for object detection. Despite its wide acceptance, it has a number of shortcomings, the most important of which are (i) the inability to distinguish very different RP curves, and (ii) the lack of directly measuring bounding box localization accuracy. In this paper, we propose 'Localization Recall Precision (LRP) Error', a new metric which we specifically designed for object detection. LRP Error is composed of three components related to localization, false negative (FN) rate and false positive (FP) rate. Based on LRP, we introduce the 'Optimal LRP', the minimum achievable LRP error representing the best achievable configuration of the detector in terms of recall-precision and the tightness of the boxes. In contrast to AP, which considers precisions over the entire recall domain, Optimal LRP determines the 'best' confidence score threshold for a class, which balances the trade-off between localization and recall-precision. In our experiments, we show that, for state-of-the-art object (SOTA) detectors, Optimal LRP provides richer and more discriminative information than AP. We also demonstrate that the best confidence score thresholds vary significantly among classes and detectors. Moreover, we present LRP results of a simple online video object detector which uses a SOTA still image object detector and show that the class-specific optimized thresholds increase the accuracy against the common approach of using a general threshold for all classes. At https://github.com/cancam/LRP we provide the source code that can compute LRP for the PASCAL VOC and MSCOCO datasets. Our source code can easily be adapted to other datasets as well.Comment: to appear in ECCV 201

Is Alpha-Synuclein Loss-of-Function a Contributor to Parkinsonian Pathology? Evidence from Non-human Primates

Accumulation of alpha-synuclein (α-syn) in Lewy bodies and neurites of midbrain dopamine neurons is diagnostic for Parkinson’s disease (PD), leading to the proposal that PD is a toxic gain-of-function synucleinopathy. Here we discuss the alternative viewpoint that α-syn displacement from synapses by misfolding and aggregation results in a toxic loss-of-function. In support of this hypothesis we provide evidence from our pilot study demonstrating that knockdown of endogenous α-syn in dopamine neurons of nonhuman primates reproduces the pattern of nigrostriatal degeneration characteristic of PD

Stability of central finite difference schemes for the Heston PDE

This paper deals with stability in the numerical solution of the prominent Heston partial differential equation from mathematical finance. We study the well-known central second-order finite difference discretization, which leads to large semi-discrete systems with non-normal matrices A. By employing the logarithmic spectral norm we prove practical, rigorous stability bounds. Our theoretical stability results are illustrated by ample numerical experiments

Small grid embeddings of 3-polytopes

We introduce an algorithm that embeds a given 3-connected planar graph as a convex 3-polytope with integer coordinates. The size of the coordinates is bounded by $O(2^{7.55n})=O(188^{n})$. If the graph contains a triangle we can bound the integer coordinates by $O(2^{4.82n})$. If the graph contains a quadrilateral we can bound the integer coordinates by $O(2^{5.46n})$. The crucial part of the algorithm is to find a convex plane embedding whose edges can be weighted such that the sum of the weighted edges, seen as vectors, cancel at every point. It is well known that this can be guaranteed for the interior vertices by applying a technique of Tutte. We show how to extend Tutte's ideas to construct a plane embedding where the weighted vector sums cancel also on the vertices of the boundary face

Serum N-Terminal propeptide of collagen type I is associated with the number of bone Metastases in breast and prostate cancer and correlates to other bone related markers

Background A number of biomarkers have been proven potentially useful for their ability to indicate bone metastases (BM) in cancer patients. The aim of this study was to investigate the relative utility of a newly developed N-terminal propeptide of collagen type I (PINP) human serum assay for the detection of BM in cancer patients. This assay has a corresponding rat PINP assay which in the future might help in translational science between rodent and human trials. Methods Participants were 161 prostate, lung and breast cancer patients stratified by number of BM(Soloway score). PINP was assessed and correlated to number of BM. Additionally, the PINP marker was correlated to bone resorption of young (ALPHA CTX-I)- and aged bone (BETA CTX-I); number of osteoclasts (Tartrate-resistant acid phosphatase 5b, TRACP5B) and osteoclast activity (CTX-I/TRACP5B). Results PINP was significantly elevated in breast- and prostate cancer patients +BM, compared to –BM ( P < 0.001), however not in lung cancer patients. A strong linear association was seen between PINP and the number of BMs. Significant elevation of PINP was observed at Soloway scores 1–4 (<0 BM) compared with score 0 (0 BM) ( P < 0.001). The correlation between bone resorption of young bone or aged bone and bone formation was highly significant in patients +BM and –BM ( P < 0.0001). Conclusions Data suggest that the present PINP potentially could determine skeletal involvement in patients with breast or prostate cancer. Correlations suggested that coupling between bone resorption and bone formation was maintained in breast- and prostate cancer patients

Planning and Leveraging Event Portfolios: Towards a Holistic Theory

This conceptual paper seeks to advance the discourse on the leveraging and legacies of events by examining the planning, management, and leveraging of event portfolios. This examination shifts the common focus from analyzing single events towards multiple events and purposes that can enable cross-leveraging among different events in pursuit of attainment and magnification of specific ends. The following frameworks are proposed: (1) event portfolio planning and leveraging, and (2) analyzing events networks and inter-organizational linkages. These frameworks are intended to provide, at this infancy stage of event portfolios research, a solid ground for building theory on the management of different types and scales of events within the context of a portfolio aimed to obtain, optimize and sustain tourism, as well as broader community benefits