bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seed size effects and competitive ability in Thlaspi arvense L. (Brassicaceae)
Authors: Susko David J. , Cavers Paul B. 
Published: January 2010

We examined the effects of seed size on plant size and competitive ability of Thlaspi arvense L. grown with and without intraspecific competition under contrasting soil fertility regimes. For solitary plants from each of four half-sibship families, seed mass was positively correlated with percentage germination, cotyledon size, and plant biomass after 15 d of growth, but differences in plant biomass largely disappeared at later dates. Small and large seeds of a single maternal family were sown in uniform or mixed arrangements of seed size classes (small:large; 100%:0%; 75%:25%; 50%:50%; 25%:75%; 0%:100%) at each of two densities (8 or 16 seeds·pot–1) under low and high soil nutrient regimes. In mixtures at low density under low soil fertility, plants from small seeds had significantly lower relative yields than expected. At high density, under either low or high nutrient conditions, plants from large seeds had significantly greater relative yields than expected. Hence, under most conditions, size inequalities between plants from seeds of different size resulted in a relative competitive advantage for plants from large seeds. The duration and extent of differences in plant size arising from T. arvense seeds of contrasting size depends on maternal genetic differences, intensity of intraspecific competition, and soil fertility.
Developmentally programmed and plastic processes of growth in the multistemmed understory shrub Vaccinium hirtum (Ericaceae)
Authors: Kawamura Koji , Takeda Hiroshi 
Published: January 2010

This paper investigates the developmentally programmed and plastic processes of growth in the multistemmed, deciduous shrub Vaccinium hirtum Thunb. We conducted the demographic censuses of stems and the measurements of stem growth and morphology along a natural light gradient in forest understory. With light availability from 5%–28%, the probability of sprouting new stems increased three-fold. Sprouts growing in well-lit conditions were larger than sprouts growing less light. In contrast, neither leaf area per unit aboveground biomass (LAR) nor relative growth rates of aboveground biomass (RGR) of individual stems changed significantly with light. Irrespective of light availability, LAR increased and RGR decreased with stem age. RGR approached zero in old stems > 12-years-old, and their aboveground biomass productions were mostly used to replace deciduous leaves. Our results suggest that the response of aboveground structures to increasing light availability occurs by the production of new sprouts, rather than by the increased growth of existing stems. This indicates a hierarchy of plasticities within the multistemmed structure. Age-related strong controls of stem development reflect the sprouting and multistemmed habits. This growth strategy is favorable under high-stress environments with generally low resource levels such as forest understory and with unpredictable resource pulses such as caused by canopy gap disturbances.
Faster dimension reduction
Authors: Ailon Nir , Chazelle Bernard 
Published: January 2010

Data represented geometrically in high-dimensional vector spaces can be found in many applications. Images and videos, are often represented by assigning a dimension for every pixel (and time). Text documents may be represented in a vector space where each word in the dictionary incurs a dimension. The need to manipulate such data in huge corpora such as the web and to support various query types gives rise to the question of how to represent the data in a lower-dimensional space to allow more space and time efficient computation. Linear mappings are an attractive approach to this problem because the mapped input can be readily fed into popular algorithms that operate on linear spaces (such as principal-component analysis, PCA) while avoiding the curse of dimensionality.
The fact that such mappings even exist became known in computer science following seminal work by Johnson and Lindenstrauss in the early 1980s. The underlying technique is often called "random projection." The complexity of the mapping itself, essentially the product of a vector with a dense matrix, did not attract much attention until recently. In 2006, we discovered a way to "sparsify" the matrix via a computational version of Heisenberg's Uncertainty Principle. This led to a significant speedup, which also retained the practical simplicity of the standard Johnson-Lindenstrauss projection. We describe the improvement in this article, together with some of its applications.
It takes two to tango
Authors: Mehta Nikhil , Mehta Anju 
Published: January 2010

Introduction

The IT outsourcing, industry landscape is dotted with broken contracts - results of unsuccessful client-vendor (C-V) partnerships. Approximately 78% C-V partnerships fail in the long term, inflicting high transition costs on clients. The recent economic downturn has strined C-V partnerships further. Despite the criticality of this issue, there is a relative lack of efforts to understand the issues leading to failed partnerships.
We discuss these issues in light of the clients' onus towards improving the longevity of C-V partnerships.
We adopt a two-pronged approach. First, we try to identify the client characteristics that influence their potential to forge a long-term C-V partnership. To that extent, we discuss a partnership maturity curve (PMC), which categorizes clients into three dynamic stages, and predicts their potential for developing mature partnerships based on their outsourcing objectives and their fit with vendors' capabilities (see Figure 1).
Second, we try to understand vendors' perspective on the issue. We interviewed 21 executives in nine established IT-outsourcing vendors in India. It has been recommended that vendors' perspective is critical to understanding C-V partnerships. Vendors highlighted an interesting mix of their own as well as client-generated issues, which we discuss in light of the client dynamics identified by PMC, to propse guidelines for clients interested in developing successful C-V partnerships. The study confirms existing belief that improving the longevity of C-V partnerships requires relational investments from clients. We identify various areas for clients to make such investments.
Probabilistic static pruning of inverted files
Authors: Blanco Roi , Barreiro Alvaro 
Published: January 2010

Information retrieval (IR) systems typically compress their indexes in order to increase their efficiency. Static pruning is a form of lossy data compression: it removes from the index, data that is estimated to be the least important to retrieval performance, according to some criterion. Generally, pruning criteria are derived from term weighting functions, which assign weights to terms according to their contribution to a document's contents. Usually, document-term occurrences that are assigned a low weight are ruled out from the index. The main assumption is that those entries contribute little to the document content.
We present a novel pruning technique that is based on a probabilistic model of IR. We employ the Probability Ranking Principle as a decision criterion over which posting list entries are to be pruned. The proposed approach requires the estimation of three probabilities, combining them in such a way that we gather all the necessary information to apply the aforementioned criterion.
We evaluate our proposed pruning technique on five TREC collections and various retrieval tasks, and show that in almost every situation it outperforms the state of the art in index pruning. The main contribution of this work is proposing a pruning technique that stems directly from the same source as probabilistic retrieval models, and hence is independent of the final model used for retrieval.
An exploration of the current state of information assurance education
Authors: Cooper Stephen , Nickell Christine , Piotrowski Victor , Oldfield Brenda , Abdallah Ali , Bishop Matt , Caelli Bill , Dark Melissa , Hawthorne E. K. , Hoffman Lance , Pérez Lance C. , Pfleeger Charles , Raines Richard , Schou Corey , Brynielsson Joel 
Published: January 2010

Information Assurance and computer security are serious worldwide concerns of governments, industry, and academia. Computer security is one of the three new focal areas of the ACM/IEEE's Computer Science Curriculum update in 2008. This ACM/IEEE report describes, as the first of its three recent trends, "the emergence of security as a major area of concern." The importance of Information Assurance and Information Assurance education is not limited to the United States. Other nations, including the United Kingdom, Australia, New Zealand, Canada, and other members from NATO countries and the EU, have inquired as to how they may be able to establish Information Assurance education programs in their own country.
The goal of this document is to explore the space of various existing Information Assurance educational standards and guidelines, and how they may serve as a basis for helping to define the field of Information Assurance. It was necessary for this working group to study what has been done for other areas of computing. For example, computer science (CS 2008 and associate-degree CS 2009), information technology (IT 2008), and software engineering (SE 2004), all have available curricular guidelines.
In its exploration of existing government, industry, and academic Information Assurance guidelines and standards, as well as in its discovery of what guidance is being provided for other areas of computing, the working group has developed this paper as a foundation, or a starting point, for creating an appropriate set of guidelines for Information Assurance education. In researching the space of existing guidelines and standards, several challenges and opportunities to Information Assurance education were discovered. These are briefly described and discussed, and some next steps suggested.
NetReplay
Authors: Anand Ashok , Akella Aditya 
Published: January 2010

In this paper, we describe Net-Replay, a new network primitive to help application end points conduct in-band characterization of the glitches they encountered. In Net-Replay, each network infrastructure element remembers a small amount of information for every packet observed at the element over a certain time interval. Furthermore, network elements expose a simple "packet marking" interface, using which they can indicate to end-points whether or not they had seen a particular packet in the past. When application end-points observe glitches, they replay (i.e. retransmit) the packets which observed the glitch and leverage feedback from network elements to determine the type and location of the glitch encountered by the packets. We discuss how end-host network stacks should be modified to leverage Net-Replay in this fashion. We also consider how network infrastructure can support Net-Replay in a lowoverhead fashion.
We argue that Net-Replay can enable applications to detect a variety of glitches and react to them in an accurate and informed manner, while ensuring that the infrastructure stays simple and fast. We believe that proactive support from the network in the form of Net-Replay-like functionality is crucial to ensure robust performance of future Internet applications, many of which are likely to be highly demanding and far less tolerant of network glitches than traditional applications.
A weighted spectrum metric for comparison of internet topologies
Authors: Fay Damien , Haddadi Hamed , Moore Andrew W. , Mortier Richard , Uhlig Steve , Jamakovic Almerima 
Published: January 2010

Comparison of graph structures is a frequently encountered problem across a number of problem domains. Comparing graphs requires a metric to discriminate which features of the graphs are considered important. The spectrum of a graph is often claimed to contain all the information within a graph, but the raw spectrum contains too much information to be directly used as a useful metric. In this paper we introduce a metric, the weighted spectral distribution, that improves on the raw spectrum by discounting those eigenvalues believed to be unimportant and emphasizing the contribution of those believed to be important.
We use this metric to optimize the selection of parameter values for generating Internet topologies. Our metric leads to parameter choices that appear sensible given prior knowledge of the problem domain: the resulting choices are close to the default values of the topology generators and, in the case of some generators, fall within the expected region. This metric provides a means for meaningfully optimizing parameter selection when generating topologies intended to share structure with, but not match exactly, measured graphs.
Poster abstract
Authors: Lee Jung Woo , Kusy Branislav , Levis Philip 
Published: January 2010

Whirlpool Ad-hoc Routing Protocol (WARP) is a dynamic data collection protocol for wireless sensor networks. Compared to existing protocols, WARP offers order of magnitude improvements in reliability, efficiency, and routing stretch for a moving data sink. When the sink moves, nearby WARP nodes stop forwarding data directly towards the sink. Instead, they speculatively disseminate data packets along loops centered at the last location of the sink. The loop radius progressively increases searching more widely until the sink is found. Finally, WARP embeds a few bits of control information in data packets and aggressively suppresses control packets to further improve its efficiency.
We have implementedWARP in TinyOS and evaluated it against the Collection Tree Protocol (CTP) [2], the state-of-art collection protocol for WSNs. For a mobile sink, WARP had significantly better reliability and efficiency, achieving over 90% reliability for a wide range of speeds and data rates, compared to below 10% reliability of CTP.
A Continuation Method for Weakly Kannan Maps
Authors: Ariza-Ruiz David , Jiménez-Melado Antonio 
Published: January 2010

AbstractThe first continuation method for contractive maps in the setting of a metric space was given by Granas. Later, Frigon extended Granas theorem to the class of weakly contractive maps, and recently Agarwal and O'Regan have given the corresponding result for a certain type of quasicontractions which includes maps of Kannan type. In this note we introduce the concept of weakly Kannan maps and give a fixed point theorem, and then a continuation method, for this class of maps.
Did Theophrastus Reject Aristotle’s Account of Place?
Authors: Morison Ben 
Published: January 2010

AbstractIt is commonly held that Theophrastus criticized or rejected Aristotle’s account of place. The evidence that scholars put forward for this view, from Simplicius’ commentary on Aristotle’s Physics, comes in two parts: (1) Simplicius reports some aporiai that Theophrastus found for Aristotle’s account; (2) Simplicius cites a passage of Theophrastus which is said to ‘bear witness’ to the theory of place which Simplicius himself adopts (that of his teacher Damascius) ‐ a theory which is utterly different from Aristotle’s. But the aporiai have relatively straightforward solutions, and we have no reason to suppose that Theophrastus didn’t avail himself of them (and some reason to think that he did). Moreover, the text which Simplicius cites as bearing witness to Damascius’ view on closer inspection does not seem to be inconsistent with Aristotle’s account of place or natural motion.
Plants producing pyrrolizidine alkaloids: sustainable tools for nematode management?
Authors: Boppré Michael , Thoden Tim 
Published: January 2010

Abstract1,2-dehydropyrrolizidine ester alkaloids (pyrrolizidine alkaloids; PAs) are a class of secondary plant metabolites found in hundreds of plant species. In vitro, PAs are known to affect plant-parasitic nematodes. Thus, PA-producing plants might be used in nematode management. So far, however, Crotalaria is the only PA-producing plant that has been used for nematode control. Consequently, we reviewed the literature on other PA plants and their effects on nematodes. This included the analysis of in vitro experiments with PA plant extracts, host tests with PA plants, as well as experiments in which PA-producing plants were used as different types of soil amendments (mulch, in situ mulching, extracts). Our results clearly show that, in addition to Crotalaria, certain other PA-producing plant species have the potential to be used in sustainable nematode management. This is especially true for management of sedentary endoparasitic nematode species. Promising applications include the use of PA plant extracts and mulches, as well as the use of PA plants for in situ mulching.
Type specimens deposited at the University of California Riverside Nematode Collection
Authors: Mundo-Ocampo Manuel , Baldwin James 
Published: January 2010

AbstractThe University of California Riverside Nematode Collection (UCRNC) was founded by S.A. Sher in 1953. Today it includes ca 35 000 slides and nearly 180 000 mounted specimens of nematodes from around the world, soil Tylenchida being particularly strongly represented. In addition to material mounted on slides, the collection is a repository for vials of bulked collections, scanning electron micrographs and a supporting reprint collection. The collection of name-bearing types, with more than 3200 slides, is published herein.
Acrostichus puri n. sp. (Nematoda: Diplogastridae), a phoretic associate of Augochlora pura mosieri Cockerell (Hymenoptera: Halictidae)
Authors: Zeng Yongsan , Thomas W. Kelley , Kanzaki Natsumi , Center Barbara , Giblin-Davis Robin , Ye Weimin 
Published: January 2010

AbstractAcrostichus puri n. sp., isolated from the body of a sweat bee, Augochlora pura mosieri, is described and figured. The new species is morphologically, molecularly and biologically very similar to A. halicti, i.e., these two species share a very complicated gubernaculum structure, distally hooked spicules with a triangular flap-like rostrum, stomatal polymorphism and synchronised associations with halcitid bees. The new species can be distinguished from A. halicti by its spicule morphology, distinctive squared manubrium and sharply bent (= ca 90° or L-shaped) distal tip vs an indistinctive rounded manubrium and a strongly recurved (= ca 180° or U-shaped) distal tip; gubernaculum with narrower, longer, anterior part and more complex posterior part than A. halicti, and tail of both sexes, with a long and filiform spike on the male or female tail vs a short spike (male) or conical tail (female). These two species also differ from each other by significant molecular sequence differences in SSU (2.0%), D2/D3 LSU (4.5%) and mtCOI (9.2%), and are reproductively incompatible in mating tests.
Diversity and distribution of nematodes associated with wild bees in Turkey
Authors: Keskin Nevin , Hazir Selcuk , Giblin-Davis Robin , Thomas W. Kelley , Hazir Canan , Ye Weimin , Scheuhl Erwin 
Published: January 2010

AbstractThe diversity and distribution of nematodes associated with soil-dwelling bees in Turkey were examined. A total of 9456 wild bees were collected and dissected to detect nematodes and 173 female and 22 male bees were positive for an overall association level of 2.1%. Halictus resurgens was the most commonly collected bee found with nematodes with 82 and 19 nematode-infested female and male bees, respectively. Sixty-four of the nematode isolates were recovered from the Black Sea region (32.8%), 59 from Central Anatolia (30.3%), 35 from the Mediterranean (17.9%), 24 from the Aegean (12.3%), six from Eastern Anatolia (3.1%) and seven from Southeast Anatolia (3.6%). In 3.9% of all bees of the family Halictidae (173/4417), nematodes were observed in the Dufour's gland, poison sac, oviduct, bursa copulatrix and abdominal cavity of dissected female bees and from the genital capsule of male bees. Only abdominal glands of 0.6% (21/3279) of female bees from the family Andrenidae were observed with nematodes. Nematodes were isolated from the genital capsule of one male bee from the family Melittidae. The poison sac was the organ where nematodes were most often observed but the highest number of nematodes occurred in the abdominal cavity. Most nematodes were in the dauer juvenile stage making identification difficult. Sequence analysis using LSU D2/D3 domains and a fragment of mitochondrial cytochrome oxidase I (mtCOI) allowed for putative identification of nematode isolates. Two or three species of Bursaphelenchus (B. anatolius, B. debrae, and potentially one or more cryptic species closest in morphology to B. anatolius) were isolated from six different halictid species (two genera; Halictus and Lasioglossum) from different geographical regions in Turkey. An additional four species of diplogastrid were recovered from the abdominal glands of andrenids; a new species of Koerneria from Andrena limata and a separate sister clade to Mononchoides composed of three other possible species from four Andrena species. An additional unknown species in the order Tylenchida (near Allantonematinae) was recovered from three species of Lasioglossum. No molecular data were obtained from three mermithid juveniles from two Andrena and one Halictus species because samples were lost in transit. The associations of most nematode isolates with bees of the families Halictidae and Andrenidae were hypothesised to be phoretic, whereas the tylenchid and mermithids were parasites.
Redescription of two Panamanian nematodes, Parasitodiplogaster citrinema Poinar & Herre, 1991 and P. popenema Poinar & Herre, 1991 (Nematoda: Diplogastrina)
Authors: Center Barbara , Giblin-Davis Robin , Herre E. Allen , Kanzaki Natsumi 
Published: January 2010

AbstractParasitodiplogaster citrinema and P. popenema were re-isolated from syconia of Ficus citrifolia and F. popenoei, respectively, from Barro Colorado Island, Panama, and are redescribed and figured herein. Both of these species were previously described as having a “well-developed stoma” and in the case of P. popenema with “stoma slightly longer than wide”. Re-examination of fresh material revealed that they share characteristic stomatal morphology, i.e., relatively wide and tube-like stomas with newly observed thorn-like stegostomatal teeth. This is distinctive from the other described Parasitodiplogaster species, which either have a relatively short and narrow stoma with protuberant, claw-like, teeth or a simple cylinder. In addition to the characters of the male papillae arrangement and spicule and gubernaculum morphology, these two species are distinguished from each other by newly-observed lip morphology characters, viz., P. citrinema has three small setae on the outer surface of each lip sector whereas P. popenema has smooth lips. Both P. citrinema and P. popenema appear typologically closest to P. sycophilon, which has a relatively wide and open stoma and seven pairs of male genital papillae, but were distinguished from P. sycophilon by the presence of stegostomatal teeth and the arrangement of the genital papillae.