840 research outputs found

    Promoting Soft Mast for Wildlife in Intensively Managed Forests

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    The fruit of woody plants is important as food for wildlife (Martin et al. 1951, Lay 1965). The relation of fruit production to southern forest stand conditions has been explored in only a few studies. Fruit production is greater in forest clearings than in closed forest stands (Lay 1966, Elalls and Alcaniz 1968). In Georgia slash pine (Pinus elliottii) plantations, fruit yields of shrubs are greatest in 4-yeas-old stands, and soil disturbance in site preparation greatly reduces fruit yields (Johnson and Landers 1978). Total fruit production is greatest in 5-year-old bedded loblolly pine (P. taeda) plantations in Mississippi (Campo and Hurst 1980). Data are limited, however, on how fruit yields are affected by various site preparation treatments for planting pines arid by conditions in developing pine stands over a period of years. In this study, we compare fruit production after 4 site treatments on clear-cuts 3, 5, and 8 growing seasons after pine planting

    "Make Them Change it Every Week!": A Qualitative Exploration of Online Developer Advice on Usable and Secure Authentication

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    Usable and secure authentication on the web and beyond is mission-critical. While password-based authentication is still widespread, users have trouble dealing with potentially hundreds of online accounts and their passwords. Alternatives or extensions such as multi-factor authentication have their own challenges and find only limited adoption. Finding the right balance between security and usability is challenging for developers. Previous work found that developers use online resources to inform security decisions when writing code. Similar to other areas, lots of authentication advice for developers is available online, including blog posts, discussions on Stack Overflow, research papers, or guidelines by institutions like OWASP or NIST. We are the first to explore developer advice on authentication that affects usable security for end-users. Based on a survey with 18 professional web developers, we obtained 406 documents and qualitatively analyzed 272 contained pieces of advice in depth. We aim to understand the accessibility and quality of online advice and provide insights into how online advice might contribute to (in)secure and (un)usable authentication. We find that advice is scattered and that finding recommendable, consistent advice is a challenge for developers, among others. The most common advice is for password-based authentication, but little for more modern alternatives. Unfortunately, many pieces of advice are debatable (e.g., complex password policies), outdated (e.g., enforcing regular password changes), or contradicting and might lead to unusable or insecure authentication. Based on our findings, we make recommendations for developers, advice providers, official institutions, and academia on how to improve online advice for developers.Comment: Extended version of the paper that appears at ACM CCS 2023. 18 pages, 4 figures, 11 table

    Classification of time series by shapelet transformation

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    Time-series classification (TSC) problems present a specific challenge for classification algorithms: how to measure similarity between series. A \emph{shapelet} is a time-series subsequence that allows for TSC based on local, phase-independent similarity in shape. Shapelet-based classification uses the similarity between a shapelet and a series as a discriminatory feature. One benefit of the shapelet approach is that shapelets are comprehensible, and can offer insight into the problem domain. The original shapelet-based classifier embeds the shapelet-discovery algorithm in a decision tree, and uses information gain to assess the quality of candidates, finding a new shapelet at each node of the tree through an enumerative search. Subsequent research has focused mainly on techniques to speed up the search. We examine how best to use the shapelet primitive to construct classifiers. We propose a single-scan shapelet algorithm that finds the best kk shapelets, which are used to produce a transformed dataset, where each of the kk features represent the distance between a time series and a shapelet. The primary advantages over the embedded approach are that the transformed data can be used in conjunction with any classifier, and that there is no recursive search for shapelets. We demonstrate that the transformed data, in conjunction with more complex classifiers, gives greater accuracy than the embedded shapelet tree. We also evaluate three similarity measures that produce equivalent results to information gain in less time. Finally, we show that by conducting post-transform clustering of shapelets, we can enhance the interpretability of the transformed data. We conduct our experiments on 29 datasets: 17 from the UCR repository, and 12 we provide ourselve

    Report of the Regional Coordination Meeting for the North Atlantic (RCM NA) 2015

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    The 12th RCM North Atlantic was held in Hamburg (Germany) 14-18 September 2015. The main purpose of the RCM is to coordinate the National Programmes (NP) of the Member States (MS) in the North Atlantic region. National Programmes for 2011-2013 have been rolled over for the period 2014-2016. Therefore, the main focus at this year was to improve regional data collection, analysis and storage and the evolution towards Regional Coordination Groups (RCG).The impact of the introduction of the landing obligation and preparations for its implementation was also discussed taking into account possible changes in scientific sampling schemes. The participation of four National Correspondents make possible to address National administration issues related to the oncoming EU MAP. A data call was launched by the chairs of the RCM NA, RCM Baltic and RCM NS&EA where MS were requested to upload data for 2014 in the regional database (RDB Fishframe) hosted by ICES. All MS except France and Northern Ireland complied with this request on landings and effort data. All MS except France uploaded sample data for 2014. French data were available for the meeting using a web base interface. Evaluation of the data call for submission data to the RDB revealed the numbers of species in landings and sample data and the numbers of metiers in effort data are in general data stable. RCM NA see big improvements in the work MS are doing regarding data calls coming from a situation where some countries didn´t provide any data to a new scenario where everyone is providing data; at the same time the overall quality has significantly improved, which is a large step forward. Regional data collection, analysis, storage and the evolution towards Regional Coordination Groups (RCG). Optimizing and harmonizing fisheries management across MS is dependent on improving regional coordination. The group discussed various needs and aspects relevant for facilitating future work of the RCM. Future tasks for the RCM don’t differ much from the current tasks. The discussion was focused on the structure of the RCGs, funding and short term needs to address tasks in an efficient way in the future. Regional coordination encompasses many different aspects, ranging from regional cooperation, sampling design, quality control procedures, data storage and analysis to the actual coordination, reporting and accountancy. Current task sharing and coordination procedures as well as future mechanisms are partially covered under the current MARE study 2014/19 (FISHPI). The project and its progress were presented to the group. The outcomes of this study will demonstrate future procedures based on case studies. As substantial effort and costs are involved to facilitate the process of regional coordination, the group highlighted the importance to access to budgets to cover these costs. Development of the RDB is also crucial for future work of the RCGs; funds are needed for the development. Additionally, RCM NA identified 4 supra regional topics where work can be done intersesionally in cooperation with the rest of RCMs: (1) Cost sharing of funding surveys; (2) Impact of landing obligation; (3) reviewing the ICES list of data needs ; and (4) review and follow up on RDB upload logs. Due to the importance to moving to a regional catch sampling scheme, an exercise was realised using the distribution of landings by harbour and fleet segment as a proxy of sampling frames that could hypothetically operate in a regional probability based design. The exercise was based on landing weight, for the simple reason that this was the only complete variable that was available for all the various national data sets. A regional sampling design can however be optimized in any number of ways (e.g. by landings value, by métier diversity, by species diversity, by number of fishing trips). The aims and aspirations of the end users need to be defined to ascertain which is most appropriate. It is one of the overriding advantages of a regional sampling design (as opposed to the aggregation of national designs) that the overall coverage can be set out to achieve regional goals. The RCM NA analyzed and discussed the main achievements of WKISCON2. It was clear that concurrent sampling at-sea is a long-established practice in most MS and that, where it was applied, concurrent sampling of fishing trips on-shore resulted in substantial increases in species collected without jeopardizing the main uses of data. Stock assessment and discard estimation and management are the major current uses of concurrent sampling data. Concurrent sampling has also been providing other benefits than its initial reason, such as advice to local, national and international authorities, research on MSFD descriptors, mixed fisheries and gear interactions and on mortality of rare species, data-poor stocks and PETS. It was clear that concurrent sampling being a statistically valid method for species selection which has proven to fulfil different end-users needs, implementation constraints hinder concurrent sampling on-shore. Thus, in order to meet end-users needs and to overcome the constraints that may arise from the implementation of concurrent sampling in some countries, particularly on-shore, RCM NA considers that different statistically sound approaches other than concurrent sampling must be developed to be tested in the field, so they may provide useful alternatives. Introduction of the landing obligation and its impact in the implementation in scientific sampling schemes. In terms of evaluating the impact of the introduction of the Landing Obligation (LO) regulation on data collection, there is only limited experience as the current implementation only covers Pelagic and Industrial fisheries in this region but MS have or are preparing for the implementation where they can. It is currently perceived that this year is a transition period for the pelagic fisheries and that these fisheries and control agencies are not fully implementing the LO (managing but not enforcing). As a result MS did not have a lot of comments on the current year and are in general preparing for next year. During the meeting it was decided to gather further information to address this issue by getting member states who were present to fill in a table on “Monitoring the impact of the landing obligation on data collection in the North Atlantic region” outlining the current state of play. This table could be considered as a live document which should be filled in year by year as the Landing Obligation is phased in. This table will then serve to provide an historical record as countries can document the changes year by year and will also provide guidance and act as a learning tool to all member states on how other countries are implementing the LO. National administrations The group discussed the proposal for task sharing and criteria for joint surveys. RCM NS&EA and RCM NA 2014 discussed a cost model for the present joint MS financed surveys and for future joint surveys. In addition to this model, the RCM NA 2015 highlighted that four categories of surveys should be considered in relation to task sharing and criteria for joint surveys. In the light of cost sharing, the group commented that the current DCF recast proposal refers to ‘exploitation of stocks’ rather than EU TAC or landings. Given the relative stability, EU TAC shares are the preferred basis for sharing costs. The exploitation of stocks shall be interpreted as EU-TAC share as a default. In specific cases, RCGs can in the future agree on different interpretation where needed and feasible. Fully agreement among the group was concerning to the engagement and participation of National Correspondent (NC) in this meeting. The future role of the NCs in the RCG context was discussed, indicating a formal role for the NCs in the RCG process to approve and agree on regional arrangements. However, the current recast of the DCF doesn’t include the formal involvement of the NCs in the coordination procedures and meetings. RCM NA highlights this as potentially problematic for the foreseen formal role of the NCs. Other items on the agenda were the consideration of the follow up of relevant recommendations made last years by Liaison Meeting and presentations and relevant development from ICES, EC and SC-RDB

    CORUM: the comprehensive resource of mammalian protein complexes

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    Protein complexes are key molecular entities that integrate multiple gene products to perform cellular functions. The CORUM (http://mips.gsf.de/genre/proj/corum/index.html) database is a collection of experimentally verified mammalian protein complexes. Information is manually derived by critical reading of the scientific literature from expert annotators. Information about protein complexes includes protein complex names, subunits, literature references as well as the function of the complexes. For functional annotation, we use the FunCat catalogue that enables to organize the protein complex space into biologically meaningful subsets. The database contains more than 1750 protein complexes that are built from 2400 different genes, thus representing 12% of the protein-coding genes in human. A web-based system is available to query, view and download the data. CORUM provides a comprehensive dataset of protein complexes for discoveries in systems biology, analyses of protein networks and protein complex-associated diseases. Comparable to the MIPS reference dataset of protein complexes from yeast, CORUM intends to serve as a reference for mammalian protein complexes
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