bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient data aggregation and transport in wireless sensor networks
Authors: Díaz Mario. O. , Leung Kin K. 
Published: May 2009

AbstractWe consider the problem of reporting events using wireless sensor networks. To reduce the data volume generated by each event, the correlated data from the (neighboring) nodes that detect the event must be brought together to be processed and compressed before relaying the result across several hops to the data sink. This process is supported by an aggregation tree, which specifies the flow of information towards the sink. For efficiency, aggregation trees should compress the data close to their sources. We propose two solutions to the event‐triggered reporting problem. Firstly, we propose the first protocol to use a staggered schedule in the construction of the aggregation tree. Due to the use of such a schedule, our protocol divides the tree‐construction time by roughly the number of hops in the network, and this advantage comes only at the expense of a small degradation of the quality of the obtained aggregation tree. Secondly, we consider a multi‐hop cluster‐based topology with fixed aggregation points. This topology is appropriate for large networks with unreliable radio links. We approximate the optimal cluster size distribution and evaluate the improvement over a uniform cluster size distribution. Copyright © 2009 John Wiley & Sons, Ltd.
An efficient scheduling scheme with diverse traffic demands in IEEE 802.16 networks
Authors: Hou Fen , Ho Pin‐Han , Shen Xuemin (Sherman) 
Published: May 2009

AbstractIn IEEE 802.16 networks, a subscriber station (SS) could be a single mobile user, a residence house, or an office building providing Internet service for multiple customers. Considering the heterogeneity among SSs which have diverse traffic demands, in this paper, we introduce the weighted proportional fair (WPF) scheduling scheme for the Best Effort (BE) service in IEEE 802.16 networks to achieve the flexible and efficient resource allocation. We develop an analytical model to investigate the performance of WPF in terms of spectral efficiency, throughput, resource utilization, and fairness, where the Rayleigh fading channel and the adaptive modulation and coding (AMC) technique are considered. Extensive simulations are conducted to illustrate the efficiency of the WPF scheduling scheme and verify the accuracy of the analytical model. Copyright © 2009 John Wiley & Sons, Ltd.
Opportunistic user cooperative relaying in TDMA‐based wireless networks
Authors: Yuan Guangxiang , Peng Mugen , Wang Wenbo 
Published: May 2009

AbstractThis paper proposes a novel protocol based on cooperative relaying between users. The protocol takes advantage of the fact that data traffic is bursty and silent periods exist between data bursts. Rather than wasting these idle time slots, users can take advantage of them to perform cooperative relaying, obviating the need for dedicated system resources for relaying, hence using the spectrum more efficiently. The benefit of this user cooperation for the higher network layers is analyzed. The system was modeled in terms of the maximum stability region and the maximum stable throughput. Our results show that our proposed protocol provides significant performance gains compared to conventional time‐division multiple‐access (TDMA) systems, as well as cooperative relaying protocols, namely selection relaying and incremental relaying. Copyright © 2009 John Wiley & Sons, Ltd.
Top‐down particle fabrication: control of size and shape for diagnostic imaging and drug delivery
Authors: Canelas Dorian A. , Herlihy Kevin P. , DeSimone Joseph M. 
Published: May 2009

AbstractThis review discusses rational design of particles for use as therapeutic vectors and diagnostic imaging agent carriers. The emerging importance of both particle size and shape is considered, and the adaptation and modification of soft lithography methods to produce nanoparticles are highlighted. To this end, studies utilizing particles made via a process called Particle Replication In Non‐wetting Templates are discussed. In addition, insights gained into therapeutic cargo and imaging agent delivery from related types of polymer‐based carriers are considered. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:

Therapeutic Approaches and Drug Discovery > Emerging Technologies
Physicochemical factors that affect metal and metal oxide nanoparticle passage across epithelial barriers
Authors: Elder Alison , Vidyasagar Sadasivan , DeLouise Lisa 
Published: May 2009

AbstractThe diversity of nanomaterials in terms of size, shape, and surface chemistry poses a challenge to those who are trying to characterize the human health and environmental risks associated with incidental and unintentional exposures. There are numerous products that are already commercially available that contain solid metal and metal oxide nanoparticles, either embedded in a matrix or in solution. Exposure assessments for these products are often incomplete or difficult due to technological challenges associated with detection and quantitation of nanoparticles in gaseous or liquid carriers. The main focus of recent research has been on hazard identification. However, risk is a product of hazard and exposure, and one significant knowledge gap is that of the target organ dose followingin vivoexposures. In order to reach target organs, nanoparticles must first breach the protective barriers of the respiratory tract, gastrointestinal tract, or skin. The fate of those nanoparticles that reach physiological barriers is in large part determined by the properties of the particles and the barriers themselves. This article reviews the physiological properties of the lung, gut, and skin epithelia, the physicochemical properties of metal and metal oxide nanoparticles that are likely to affect their ability to breach epithelial barriers, and what is known about their fate followingin vivoexposures. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials
Phylogenetic analysis indicates transitions from vegetative to sexual reproduction in theLobaria retigeragroup (Lecanoromycetidae, Ascomycota)
Authors: CORNEJO Carolina , CHABANENKO Svetlana , SCHEIDEGGER Christoph 
Published: May 2009

AbstractPhylogenetic relationships among the hypothetical species pairsLobaria kurokawae/L. retigeraandL. pseudopulmonaria/L. isidiosawere investigated based on TLC techniques and the phylogenetic analysis of the internal transcribed spacers (ITS) nrDNA. Results of TLC demonstrate thatL. retigeraandL. kurokawaecan be chemically distinguished fromL. isidiosaandL. pseudopulmonariaby the absence of retigeranic acid. Parsimony analysis of 18 specimens shows two monophyletic clades – aL.retigeralineage and aL. isidiosalineage—both including their apotheciate counterparts. Unlike the original hypothesis of species pairs, our study reveals transitions from isidiate morphs that have the potential to rarely form apothecia, towards apotheciate morphs that produce no vegetative propagules.
Caloplaca himalayana, a new epiphytic lichen from the Indian subcontinent
Authors: JOSHI Yogesh , UPRETI Dalip K. , SATI Suresh C. 
Published: May 2009

AbstractTwenty-three species of epiphyticCaloplacaare recognized in India, of whichCaloplaca himalayanaJoshi, Y. & Upreti, characterized by thin, continuous, yellowish thallus, numerous ferruginous-red to brownish red, flat to subconvex apothecia with a persistent proper margin and lignicolous habitat, is described here as a new species. Because of the ferruginous coloured apothecial disc, the new species is provisionally placed in theferrugineagroup until a taxonomic treatment of the whole group has been carried out. Theferrugineagroup is characterized by a whitish to grey (rarely yellowish) crustose thallus, a ferruginous to rarely blackish apothecial disc, biatorine to lecanorine exciple, thick-walled spore septa and the chemosyndrome C. The taxonomic affinities of the new taxa with several other taxa, including species offerrugineagroup, are discussed. Two new records for India are also recorded:Caloplaca alnetorumGiralt, Nimis & Poelt andC. crocea(Kremp.) Hafellner & Poelt. A key to all the corticolousCaloplacaspecies occurring in the Indian subcontinent is also provided.
A new species of Graphis (Graphidaceae) from Venezuela
Authors: NEUWIRTH Gerhard , LÜCKING Robert 
Published: May 2009

AbstractA corticolous Graphis discovered in the southern part of Venezuela is described as new to science. The new species, Graphis breussii sp. nov., is characterized by rather large, prominent lirellae with striate labia and apically thin complete thalline cover, a completely carbonized exciple, four submuriform ascospores per ascus, and norstictic acid; it belongs in the Graphis acharii group.
Two new conidial lichenicolous fungi from Spain indicate the distinction ofLichenodiplisandMinutoexcipula
Authors: ATIENZA Violeta , PÉREZ-ORTEGA Sergio , ETAYO Javier 
Published: May 2009

AbstractTwo new conidial lichenicolous fungi are described from Spain:Lichenodiplis crespoaeonCyphelium notarisiiandMinutoexcipula tephromelaeonTephromela atra.Lichenodiplis crespoaediffers from all the described species of the genus in the narrower and shorter conidia, and the hostCyphelium notarisii.Minutoexcipula tephromelaeis characterized by subglobose, conidiogenous cells occasionally bearing 1–2 long proliferating extensions, short conidia and by the hostTephromela atra.
Offline decoupled path planning approach for effective coordination of multiple robots
Authors: Chiddarwar Shital S. , Babu N. Ramesh 
Published: May 2009

SUMMARYIn this paper, a decoupled offline path planning approach for determining the collision-free path of end effectors of multiple robots involved in coordinated manipulation is proposed. The proposed approach for decoupled path planning is a two-phase approach in which the path for coordinated manipulation is generated with a coupled interaction between collision checking and path planning techniques. Collision checking is done by modelling the links and environment of robot using swept sphere volume technique and utilizing minimum distance heuristic for interference check. While determining the path of the end effector of robots involved in coordinated manipulation, the obstacles present in the workspace are considered as static obstacles and the links of the robots are viewed as dynamic obstacles by the other robot. Coordination is done in offline mode by implementing replanning strategy which adopts incremental A* algorithm for searching the collision-free path. The effectiveness of proposed decoupled approach is demonstrated by considering two examples having multiple six degrees of freedom robots operating in 3D work cell environment with certain static obstacles.
An adaptive niching genetic algorithm approach for generating multiple solutions of serial manipulator inverse kinematics with applications to modular robots
Authors: Tabandeh Saleh , Melek William W. , Clark Christopher M. 
Published: May 2009

SUMMARYInverse kinematics (IK) is a nonlinear problem that may have multiple solutions. A modified genetic algorithm (GA) for solving the IK of a serial robotic manipulator is presented. The algorithm is capable of finding multiple solutions of the IK through niching methods. Despite the fact that the number and position of solutions in the search space depends on the position and orientation of the end-effector as well as the kinematic configuration (KC) of the robot, the number of GA parameters that must be set by a user are limited to a minimum through the use of an adaptive niching method. The only requirement of the algorithm is the forward kinematics (FK) equations which can be easily obtained from the Denavit–Hartenberg link parameters and joint variables of the robot. For identifying and processing the outputs of the proposed GA, a modified filtering and clustering phase is also added to the algorithm. For the postprocessing stage, a numerical IK solver is used to achieve convergence to the desired accuracy. The algorithm is validated on three KCs of a modular and reconfigurable robot (MRR).
The functions of English in Nigeria from the earliest times to the present day
Authors: Taiwo Rotimi 
Published: May 2009

ABSTRACTThe use of the English language in Nigeria dates back to the late sixteenth and early seventeenth century when British merchants and Christian missionaries settled in the coastal towns called Badagry, near Lagos in the present day South Western Nigeria and Calabar, a town in the present day South Eastern Nigeria. The merchants initially traded in slaves until the slave trade was abolished in 1807, at which time freed slaves of Nigerian origin returned to the country. Many of them, who had been exposed to Western education and Christianity, later served as translators or interpreters for the Christian missionaries. The primary aim of the Christian mission was not to make their converts speak English; rather, it was to make them literate enough to read the bible in their indigenous languages. This must be the reason why Samuel Ajayi Crowder translated the English bible into Yoruba, the major language in South Western Nigeria.With the attainment of independence, English gradually grew to become the major medium for inter-ethnic communication. Like most African nations, the country, after independence, had to grapple with multi-ethnicity and acute multilingualism. In this article, we shall examine the expansion in the functions of English during the post-colonial period.
English railway announcements in Singapore
Authors: Poole Brian 
Published: May 2009

ABSTRACTSingapore's Mass Rapid Transit (MRT) railway system is a highly effective and rather inexpensive way of getting around the Lion City, although locals sometimes complain about overcrowding in the carriages and about noise levels experienced in apartment blocks situated near the lines. Generally speaking, passengers are well provided with information too, including maps of the MRT system in the stations, screen data about train arrivals, and clearly enunciated announcements (in English, Mandarin, Malay and Tamil) inside the carriages about upcoming stations and connections. However, one quibble can be raised about the English version of these announcements, which sometimes features the verb ‘to alight’. This is explored.
‘World English’ and the Latin analogy: where we get it wrong
Authors: Rajagopalan Kanavillil 
Published: May 2009

ABSTRACTWill World English go the way of Latin? The phrase ‘Latin analogy’ was, it seems, coined by McArthur (1987), who distinguished a pessimistic or what he called ‘Babelesque’, perspective from an optimistic and a neutral (or pragmatic) perspectives to the comparison. The comparison continues to be made even today and generally it comes with a dire warning: the days of English as an international language, or a lingua franca for peoples from different parts of the world, are numbered. It will, sooner or later, break up into a number of different, mutually incomprehensible languages just the way good old Latin did. What is worse, in some cases this apprehension seems only to grow with the passage of time.
The final future of t
Authors: Bulley Michael 
Published: May 2009

ABSTRACTWill the final t become totally bottled up? It was about 15 years ago, I suppose, that I was told by an 18-year-old student that you shouldn't pronounce the final t in words like went. She meant in no circumstances. So struck was I by this that I reflected on my own practice, as a British English speaker, with such words. I decided that, in general, I released a final t before a following vowel, before a pause and before ‘soft’ consonants like h or w, but might sometimes keep it in before a ‘strong’ consonant, like m or b. So, I would say ‘I went away’, ‘What?’ and ‘That hospital’, but, pre-consonantal, either ‘He sent bottled water’ or ‘He sen’ bottled water’. You would, of course, refer also to words spelled with te at the end, like mate, as being pronounced with a final t.Since that time, and particularly in recent years, I have noticed an increase in the non-released version of final t, pre-vowel or pre-pause, from BrE speakers in contexts where before I would not have expected it, as, for example, from BBC newsreaders.
‘Sweet as!’: the intensifier as in New Zealand and Australian English
Authors: Sowa Joseph 
Published: May 2009

ABSTRACTThe use of ‘as’ as a post-modifying intensifier is a construction that has become well-established in Australian and New Zealand English but is rare elsewhere. Only recently has its usage begun to be studied. In 2002, Laurie Bauer and Winifred Bauer included adj + as in their study of intensifier usage among middle-school aged children in New Zealand. Later, in 2006, Michael Head and Peter Petrucci built on Bauer and Bauer's work by studying this specific construction using the Wellington Corpus of Spoken New Zealand English (WSC) and quotations in newspaper articles. Since these studies, adj + as has become increasingly grammaticalised, as evidenced by its use in the predicate and attributive positions, its modification by adverbs, and its use as an adverb. The usage is further examined in this article.
Conference Report: IAWE14, Hong Kong, 1–5 December 2008
Authors: van Rooy Bertus 
Published: May 2009

ABSTRACTA report on the Fourteenth Annual Conference of the International Association for World Englishes was held from 1–5 December 2008 at the City University of Hong Kong. The Conference Theme was ‘World Englishes and World's Languages: Convergence, Enrichment or Death?’ On the first two days, three pre-conference workshops and an open forum discussion were held, addressing theory and methodology in the world Englishes classroom, creativity in world Englishes and the implications of language variation for classroom teaching. This was followed by three packed days of presentations, including a keynote, plenary and presidential address, four focus lectures, and eight streams of parallel paper presentations or special panels/thematic sessions. In total, more than 150 presentations were made, and the conference was attended by well over 200 delegates.
Delivery of Complex Organic Compounds from Planetary Nebulae to the Solar System
Authors: Kwok Sun 
Published: May 2009

AbstractInfrared spectroscopic observations of planetary nebulae and proto-planetary nebulae have shown that complex organic compounds are synthesized in these objects over periods as short as a thousand years. These compounds are ejected into the interstellar medium and spread throughout the Galaxy. Evidence from meteorites has shown that these stellar grains have reached the Solar System, and may have showered the Earth during the heavy bombardment stage of the Early Earth. In this paper, we discuss the chemical structure of stellar organic grains and compare them to the organic matter found in meteorites, comets, asteroids, planetary satellites, and interplanetary particles. The possibility that the early Solar System was chemically enriched by organic compounds ejected from distant stars is presented.
The interplay between central and sub-central levels: the development of a systemic standard based programme for governing medical performance in Denmark
Authors: VRANGBAEK KARSTEN 
Published: May 2009

AbstractThis paper analyses the introduction of a systemic standards based programme for governing medical performance in Denmark. The programme combines clinical, organisational, and patient related standards and measures, and contains both external evaluation and self-assessment based on standards. The substance of the programme is new compared to the previous decentralised or professionally driven state of affairs that was based on a largely voluntary introduction of clinical standards, combined with a case-by-case evaluation of malpractice incidents. The programme strengthens hierarchy-based forms of governance; these co-exist with salient components of network-based governance as well as some elements of market-based governance. Institutional and contextual factors are important in explaining why a systemic standards based programme emerged as a result of the policy negotiation processes. In particular, the programme reflects stronger governance ambitions from the government in response to claims of a relative decline in the quality of the regional health services. However, the actual design is mediated by institutionalised negotiation processes among the state, decentralised authorities, and health professionals.
Capacity and authority: comments on governing doctors and health care
Authors: WHITE JOSEPH 
Published: May 2009

AbstractThis stimulating set of articles provides intriguing information and comments about medical governance in four countries. The commentary argues that the typology of governance approaches is not as useful as one would want for understanding either the political prospects or policy effects of governance measures. The politics of governance measures is distinctly related to efforts to avoid blame, and the effects of measures are better understood in terms of state capacity and a term, ‘authority’, that advocates of ‘governance’ usually avoid. Close attention to the requisites of authority provides some insight into the patterns of adoption and consequences of measures. These patterns are highlighted by comparing the four cases reviewed to experience in the United States.
Digital BioCuration: A Question of Balance
Authors: Ostell James 
Published: May 2009

AbstractCuration of biomedical data has come to encompass a broad range of activities and considerations, which include the building of digital archives, making decisions on the relative value and longevity of one dataset vs another, editing data records manually, performing or assessing computational processes over very large sets of data, and grappling with issues of web usability and data standards. People who consider themselves biological curators may range from a single domain expert, who develops a collection which reflects their personal judgments and priorities, to groups of people supporting large, long term public resources such as GenBank, RefSeq, or PubMed, and everything in between. Finding the right balance between objective measures of quality and personal judgment, between computational measures and manual curation, between published results in journals and active curation of databases varies by project but some common themes and considerations recur in our experiences of the past two decades at NCBI.