bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of surgical and electrodiagnostic findings in single root lumbosacral radiculopathies
Authors: Tsao Bryan E. , Levin Kerry H. , Bodner Russ A. 
Published: January 2003

AbstractTo identify the segmental innervation of L‐2–S‐1 muscles, we compared the preoperative electrodiagnostic examinations of 45 patients with single‐level lumbosacral radiculopathies confirmed radiologically and surgically. The electrodiagnostic findings were classified as abnormal only by the needle examination and only if muscles demonstrated active denervation or a marked neurogenic motor unit potential firing pattern. In comparison to other surgical, intraoperative root stimulation, and clinical studies, we found several differences. Overall, there was little overlap among L‐2–4, L‐5, and S‐1 radiculopathies. The tibialis anterior was predominantly L‐5 innervated, the gastrocnemius (medial and lateral head) predominantly S‐1 innervated, and the biceps femoris (short and long head) exclusively S‐1 innervated. The two heads of biceps femoris were not affected in any patients with L‐5 radiculopathy in whom they were examined. These findings help guide both the clinician and surgeon in the diagnosis and treatment of lumbosacral radiculopathies. Muscle Nerve 27: 60–64, 2003
The utility of segmental nerve conduction studies in ulnar mononeuropathy at the elbow
Authors: Azrieli Yevgeny , Weimer Louis , Lovelace Robert , Gooch Clifton 
Published: January 2003

AbstractPatients with clinical evidence of ulnar mononeuropathy at the elbow may have normal routine motor and sensory nerve conduction studies, suggesting a low sensitivity for these methods. Other, more specialized techniques may have a higher sensitivity, increasing diagnostic yield, and provide more specific localization of the lesion. We compared the sensitivity and specificity of ulnar segmental nerve conduction studies (SgNCS or “inching”) at 2‐cm intervals with those of routine ulnar motor and sensory studies. We studied 21 arms with symptoms or signs of ulnar neuropathy and 25 asymptomatic control arms. SgNCS proved significantly more sensitive than more routine studies in diagnosing ulnar neuropathy at the elbow, with a sensitivity of 81%, whereas motor conduction velocity in a longer (10–14 cm) segment across the elbow was the next most sensitive at 24%. Recording from the first dorsal interosseous muscle did not improve sensitivity when compared with recording from the abductor digiti quinti. Short SgNCS significantly improves detection of ulnar mononeuropathy at the elbow and should be considered when routine studies are negative and clinical suspicion remains high. Muscle Nerve 27: 46–50, 2003
Ryanodine receptor antibodies in myasthenia gravis: Epitope mapping and effect on calcium release in vitro
Authors: Skeie Geir Olve , Mygland Åse , Treves Susan , Gilhus Nils Erik , Aarli Johan Arild , Zorzato Francesco 
Published: January 2003

AbstractPatients with myasthenia gravis can have antibodies against skeletal muscle ryanodine receptor (Ry1), the sarcoplasmic reticulum calcium‐release channel, which plays a crucial role in excitation–contraction coupling. We have screened a panel of overlapping Ry1 fusion proteins with Ry1 antibody–containing myasthenia gravis sera to identify the main immunogenic region. The pc2 Ry1 fusion protein representing a Ry1 region close to the N‐terminus (residues 799–1172) was identified as the main immunogenic region for the antibodies. The binding kinetics of the Ry1 antibodies to the pc2 Ry1 fusion protein were tested using an optical biosensor. Ry1 antibodies in the IgG fraction from sera of patients with myasthenia gravis bound with high affinity and with a stoichiometry of 1:1. The functional effect of these Ry1 antibodies was tested in an in vitro Ca2+‐release assay. The Ry1 antibodies induced a twofold increase of the half‐maximal concentration for 4‐Cl‐m‐cresol–induced Ca2+ release from terminal cisternae vesicles but had no effect on Vmax. The effect on 4‐Cl‐m‐cresol–induced Ca2+ release was specific, as preincubation of the active IgG fraction with the pc2 Ry1 fusion protein abolished the inhibition. These data suggest that the Ry1 sequence defined by residues 799–1172 is involved in the regulation of Ry1 function, and that this regulation could be functionally affected in vivo in patients with myasthenia gravis. Muscle Nerve 27: 81–89, 2003
Initial semeiology in children with Charcot–Marie–Tooth disease 1A duplication
Authors: Berciano José , García Antonio , Combarros Onofre 
Published: January 2003

AbstractThe aim of this study was to describe the initial signs and symptoms in Charcot–Marie–Tooth disease type 1A (CMT‐1A). Twelve secondary cases with CMT‐1A were serially evaluated. Ages at initial clinical examination ranged between 1 month and 5 years (mean, 2 years) and final ages between 6 and 23 years (mean, 13 years). First signs of the disease were detected at initial or upon serial examinations in all 12 patients at ages ranging between 1 and 10 years (median, 4 years). The most frequent signs were lower limb areflexia in 12, difficulty in heel walking in 8, nerve enlargement in 6, atrophy of intrinsic foot muscles in 6, clawing of toes in 5, pes cavus or cavus varus in 4, shortening of Achilles tendon in 3, peroneal weakness in 1, and stocking hypoesthesia in 1. Only three patients were symptomatic at the initial evaluation. We conclude that initial CMT‐1A signs usually appear in early childhood, although they may be quite subtle and require serial examinations for detection. Lower limb areflexia is the only constant early sign. Muscle Nerve 27: 34–39, 2003
Multifacility ordered median problems on networks: A further analysis
Authors: Kalcsics Jörg , Nickel Stefan , Puerto Justo 
Published: January 2003

AbstractIn this paper, we address the ordered p‐median problem, which includes as special cases most of the classical multifacility location problems discussed in the literature. Finite dominating sets (FDS) are known for particular instances of this problem: p‐median, p‐center, and p‐centdian. We find an FDS for the ordered p‐median problem. This set allows us to gain a better insight into the general FDS structure of network location problems. This FDS is later used to present the first polynomial time algorithm for p‐facility ordered median problems on tree networks. This result is combined with some approximation algorithms to give an O(log M log log M) approximate solution of these problems on general networks, where M is the number of vertices. © 2002 Wiley Periodicals, Inc.
The SONET edge‐partition problem
Authors: Goldschmidt Olivier , Hochbaum Dorit S. , Levin Asaf , Olinick Eli V. 
Published: January 2003

AbstractMotivated by a problem arising in the design of telecommunications networks using the SONET standard, we consider the problem of covering all edges of a graph using subgraphs that contain at most k edges with the objective of minimizing the total number of vertices in the subgraphs. We show that the problem is 𝒩𝒫‐hard when k ≥ 3 and present a linear‐time

‐approximation algorithm. For even k values, we present an approximation scheme with a reduced ratio but with increased complexity. © 2002 Wiley Periodicals, Inc.
Upgrading trees under diameter and budget constraints
Authors: Chepoi Victor , Noltemeier Hartmut , Vaxès Yann 
Published: January 2003

AbstractGiven a tree T = (V, E) endowed with a length function l and a cost function c, the diameter lowering problem consists in finding the reals 0 ≤ x(e) ≤ l(e), e ∈ E such that the tree obtained from T by decreasing the length of every edge e by x(e) units has a minimal diameter subject to the constraint ∑e∈Ec(e)x(e) ≤ B, where B is the available budget (analogously, one can minimize the cost of lowering subject to a diameter constraint). We present an O(|V|2) algorithm for solving this problem by developing and using algorithms of similar complexity for related eccentricity lowering problems. © 2002 Wiley Periodical, Inc.
Toward faster algorithms for dynamic traffic assignment. I. Parametric quickest‐path trees
Authors: Dial Robert B. 
Published: January 2003

AbstractBeing first in a three‐part series promising a practical solution to the user‐equilibrium dynamic traffic assignment problem, this paper devises a parametric quickest‐path tree algorithm, whose model makes three practical assumptions: (i) the traversal time of an arc i → j is a piecewise linear function of the arrival time at its i‐node; (ii) the traversal time of a path is the sum of its arcs' traversal times; and (iii) the FIFO constraint holds, that is, later departure implies later arrival. The algorithm finds a quickest path, and its associated earliest arrival time, to every node for every desired departure time from the origin. Its parametric approach transforms a min‐path tree for one departure‐time interval into another for the next adjacent interval, whose shared boundary the algorithm determines on the fly. By building relatively few trees, it provides the topology explicitly and the arrival times implicitly of all min‐path trees. Tests show the algorithm running upward of 10 times faster than the conventional brute‐force approach, which explicitly builds a min‐path tree for every departure time. Besides dynamic traffic assignment, other applications for which these findings have utility include traffic control planning, vehicle routing and scheduling, real‐time highway route guidance, etc. © 2002 Wiley Periodicals, Inc.
Social network coordination and graph routing
Authors: Onn Shmuel , Sperber Elisheva 
Published: January 2003

AbstractWe consider the problem of coordinating robots moving on a network. Each robot is autonomous and needs to visit various sites of the network at various times. The sequence of destinations for each robot changes dynamically and unpredictably. Recently, Onn and Tennenholtz showed that the problem can be solved by introducing a social law on the network, which, once obeyed by all robots, enables each to move to any desired destination without collisions and regardless of the actions of other robots, needing neither central coordination nor mutual communication. This social law can be derived from a suitably defined routing of the graph underlying the network. Here, we study the complexity of routing. We provide an effective characterization of 2‐routable graphs, and by establishing a correspondence between hypergraph coloring and graph routing, we show that computing or approximating an optimal routing is generally hard. We also discuss routing in planar graphs, which often underlie robotic networks and show that the correspondence between coloring and routing together with the Four Color Theorem guarantee the existence of small and effectively computable routings in bipartite planar graphs of small radius. The complexity of routing arbitrary planar graphs remains open. © 2002 Wiley Periodicals, Inc.
A note on needle‐ice mound formation in the High Drakensberg, Southern Africa
Authors: Grab Stefan 
Published: January 2003

AbstractSmall needle‐ice mounds are described from the High Drakensberg. They develop infrequently during periods of several days of uninterrupted cold conditions. Ice growth incorporates sediment and stones. An accumulated segregated ice length of >41 cm was measured, with clasts heaved ∼14 cm. During subsequent thaw phases, the ice ablates from the top downwards, forming sediment veneers and cappings. These mounds contribute towards turf exfoliation, thereby exposing sediment to deflation. Copyright © 2002 John Wiley & Sons, Ltd.
Observations on a blockstream in the vicinity of Sani Pass, Lesotho highlands, Southern Africa
Authors: Boelhouwers Jan , Holness Steve , Meiklejohn Ian , Sumner Paul 
Published: January 2003

AbstractCoarse slope deposits, frequently grading into blockstreams, are common throughout the Lesotho highlands, southern Africa. This paper describes one such blockstream. It is interpreted as a typical lag deposit derived from valley‐wide colluvial mantles, which contains superimposed and incorporated Late‐Pleistocene blocky material. Blocks are largely derived from local scarps but may contain a component of corestones from mobilized regolith. The widespread mantle argues against landscape‐scale glaciation in the Lesotho highlands in the Late Pleistocene. Rather, the environment appears to have been conducive to deep seasonal frost during the period of block production. No unequivocal evidence for permafrost is found. Copyright © 2002 John Wiley & Sons, Ltd.
High‐resolution seismic and ground penetrating radar–geophysical profiling of a thermokarst lake in the western Lena Delta, Northern Siberia
Authors: Schwamborn G. J. , Dix J. K. , Bull J. M. , Rachold V. 
Published: January 2003

AbstractHigh‐resolution seismic and ground‐penetrating‐radar (GPR) data have been acquired over Lake Nikolay in the western Lena Delta in order to study the uppermost basin fill and the bordering frozen margins. GPR (100 MHz antenna pair) measurements were completed on the frozen lake and its permafrost margins, while high‐resolution seismic data were acquired from the lake during open‐water conditions in summer using a 1.5–11.5 kHz Chirp profiler. The combined use of the two profiling systems allows stratigraphic profiling in both frozen and unfrozen parts of the lake. Shallow seismic reflection images of the uppermost 4 to 5 m of sediments are compared to GPR sections, which have approximately the same horizontal and vertical resolution. Short sediment cores aid calibrate the geophysical data. Copyright © 2002 John Wiley & Sons, Ltd.
Internal structure and behaviour of a rock glacier in the Arid Andes of Argentina
Authors: Croce Flavia A. , Milana Juan P. 
Published: January 2003

AbstractThis paper reports results of the application of combined refraction and geoelectric geophysical methods to the study of the El Paso rock glacier in the arid Andes of Argentina. The data allow inferences to be made upon the internal structure, and permafrost thickness of the rock glacier. The El Paso rock glacier is located in the arid to hyper‐arid Agua Negra basin. Due to its altitude, it records some of the world's highest global radiation. The active layer thickness was studied using refraction seismic methods. Seasonal monitoring of this layer showed large variations in thickness, being thicker in summer and thinner in winter. Geoelectric methods allowed detection of a wet layer underlying permafrost, thereby providing information about the character of the rock‐glacier base. The maximum inferred thickness of El Paso permafrost was 18.5 m. Three main layers were detected: an upper deposit of dry debris over a debris‐water layer, a debris‐ice‐mixture (i.e. permafrost), and a lower one composed of wet debris. The geophysical results permit a first estimate of the volume of water (6.3 hm3) enclosed in the rock glaciers of this region, indicating that locally, rock glaciers are important water resources. However the incidence of water availability to the arid lowlands is unknown. Copyright © 2002 John Wiley & Sons, Ltd.
Modelling rock avalanches and their relation to permafrost degradation in glacial environments
Authors: Bottino Giannantonio , Chiarle Marta , Joly André , Mortara Giovanni 
Published: January 2003

AbstractHigh runout distances characterize landslides falling on glaciers because of (1) low friction offered by ice to sliding and (2) complex rock‐ice interactions that take place during mass motion. Block‐fall models (two (2D) and three dimensional (3D)) were tested on the 1936 Felik landslide (Mount Rosa Massif). Geotechnical parameters were assessed through a back‐analysis aided by field surveys, aerial photo and historical data analysis. Outcomes are verified for two rock‐ice avalanches which ran along the Brenva Glacier (Mount Blanc Massif) in 1920 and 1997. Empirical models show poor precision (75%). 3D numerical models are too complex but 2D ones gave results that pointed out that real runouts exceed predicted ones by 30%, possibly due to fluidization processes. Rock‐ice avalanches require attention because they originate in areas likely destined to experience permafrost degradation and glacier retreat. Copyright © 2002 John Wiley & Sons, Ltd.
Morphometry and environmental characteristics of turf‐banked solifluction lobes, Kluane Range, Yukon Territory, Canada
Authors: Hugenholtz Chris H. , Lewkowicz Antoni G. 
Published: January 2003

AbstractMeasurements of turf‐banked solifluction lobes at a site in the Kluane Range, Yukon Territory, are compared to observations made by L.W. Price of similar features located 50 km to the north in the Ruby Range. Both studies show that a threshold depth of snow is necessary for lobes to develop. The relative importance of solifluction on slopes with different orientations, however, is not congruent. The largest lobes at our site are present on northeast‐facing slopes and the smallest on northwest‐facing slopes. Lobe dimensions increase downslope in association with a greater organic mat thickness, a higher soil fines content, and a reduced late‐summer thaw depth. Riser heights that are large relative to tread length‐to‐width ratios are correlated with a thin organic mat, a thick active layer and a high coarse particle content. The lobe plan‐form, described by the ratio of tread length to tread width, is significantly correlated with only one biophysical variable. Mean and median length‐to‐width ratios are below unity for all aspects at our site and in several other studies, suggesting a common evolutionary form. A cycle of solifluction lobe development is proposed, in which a lobe enlarges to a maximum size that depends on micro‐site environmental characteristics. Copyright © 2002 John Wiley & Sons, Ltd.
In Vitro Assays Demonstrate That Pollen Tube Organelles Use Kinesin-Related Motor Proteins to Move along Microtubules[W]
Authors: Romagnoli Silvia , Cai Giampiero , Cresti Mauro 
Published: January 2003

AbstractThe movement of pollen tube organelles relies on cytoskeletal elements. Although the movement of organelles along actin filaments in the pollen tube has been studied widely and is becoming progressively clear, it remains unclear what role microtubules play. Many uncertainties about the role of microtubules in the active transport of pollen tube organelles and/or in the control of this process remain to be resolved. In an effort to determine if organelles are capable of moving along microtubules in the absence of actin, we extracted organelles from tobacco pollen tubes and analyzed their ability to move along in vitro–polymerized microtubules under different experimental conditions. Regardless of their size, the organelles moved at different rates along microtubules in the presence of ATP. Cytochalasin D did not inhibit organelle movement, indicating that actin filaments are not required for organelle transport in our assay. The movement of organelles was cytosol independent, which suggests that soluble factors are not necessary for the organelle movement to occur and that microtubule-based motor proteins are present on the organelle surface. By washing organelles with KI, it was possible to release proteins capable of gliding carboxylated beads along microtubules. Several membrane fractions, which were separated by Suc density gradient centrifugation, showed microtubule-based movement. Proteins were extracted by KI treatment from the most active organelle fraction and then analyzed with an ATP-sensitive microtubule binding assay. Proteins isolated by the selective binding to microtubules were tested for the ability to glide microtubules in the in vitro motility assay, for the presence of microtubule-stimulated ATPase activity, and for cross-reactivity with anti-kinesin antibodies. We identified and characterized a 105-kD organelle-associated motor protein that is functionally, biochemically, and immunologically related to kinesin. This work provides clear evidence that the movement of pollen tube organelles is not just actin based; rather, they show a microtubule-based motion as well. This unexpected finding suggests new insights into the use of pollen tube microtubules, which could be used for short-range transport, as actin filaments are in animal cells.
AtATMIs Essential for Meiosis and the Somatic Response to DNA Damage in Plants[W]
Authors: Garcia Valérie , Bruchet Hugues , Camescasse Delphine , Granier Fabienne , Bouchez David , Tissier Alain 
Published: January 2003

AbstractIn contrast to yeast or mammalian cells, little is known about the signaling responses to DNA damage in plants. We previously characterized AtATM, an Arabidopsis homolog of the human ATM gene, which is mutated in ataxia telangiectasia, a chromosome instability disorder. The Atm protein is a protein kinase whose activity is induced by DNA damage, particularly DNA double-strand breaks. The phosphorylation targets of Atm include proteins involved in DNA repair, cell cycle control, and apoptosis. Here, we describe the isolation and functional characterization of two Arabidopsis mutants carrying a T-DNA insertion in AtATM. Arabidopsis atm mutants are hypersensitive to γ-radiation and methylmethane sulfonate but not to UV-B light. In correlation with the radiation sensitivity, atm mutants failed to induce the transcription of genes involved in the repair and/or detection of DNA breaks upon irradiation. In addition, atm mutants are partially sterile, and we show that this effect is attributable to abundant chromosomal fragmentation during meiosis. Interestingly, the transcription of DNA recombination genes during meiosis was not dependent on AtATM, and meiotic recombination occurred at the same rate as in wild-type plants, raising questions about the function of AtAtm during meiosis in plants. Our results demonstrate that AtATM plays a central role in the response to both stress-induced and developmentally programmed DNA damage.
Three Isoforms of Isoamylase Contribute Different Catalytic Properties for the Debranching of Potato Glucans[W]
Authors: Hussain Hasnain , Mant Alexandra , Seale Robert , Zeeman Sam , Hinchliffe Edward , Edwards Anne , Hylton Christopher , Bornemann Stephen , Smith Alison M. , Martin Cathie , Bustos Regla 
Published: January 2003

AbstractIsoamylases are debranching enzymes that hydrolyze α-1,6 linkages in α-1,4/α-1,6–linked glucan polymers. In plants, they have been shown to be required for the normal synthesis of amylopectin, although the precise manner in which they influence starch synthesis is still debated. cDNA clones encoding three distinct isoamylase isoforms (Stisa1, Stisa2, and Stisa3) have been identified from potato. The expression patterns of the genes are consistent with the possibility that they all play roles in starch synthesis. Analysis of the predicted sequences of the proteins suggested that only Stisa1 and Stisa3 are likely to have hydrolytic activity and that there probably are differences in substrate specificity between these two isoforms. This was confirmed by the expression of each isoamylase in Escherichia coli and characterization of its activity. Partial purification of isoamylase activity from potato tubers showed that Stisa1 and Stisa2 are associated as a multimeric enzyme but that Stisa3 is not associated with this enzyme complex. Our data suggest that Stisa1 and Stisa2 act together to debranch soluble glucan during starch synthesis. The catalytic specificity of Stisa3 is distinct from that of the multimeric enzyme, indicating that it may play a different role in starch metabolism.