Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Mobile

  • highly mobile

  • Terms modified by Mobile

  • mobile ad hoc network
  • mobile application
  • mobile belt
  • mobile communication
  • mobile communication system
  • mobile device
  • mobile electronics
  • mobile element
  • mobile genetic element
  • mobile internet
  • mobile lipid
  • mobile manipulator
  • mobile mass
  • mobile network
  • mobile phase
  • mobile phase additive
  • mobile phase composition
  • mobile phase condition
  • mobile phase consisting
  • mobile phase containing
  • mobile phase ph
  • mobile phone
  • mobile phone industry
  • mobile population
  • mobile robot
  • mobile robots
  • mobile satellite
  • mobile satellite channel
  • mobile services
  • mobile species
  • mobile station
  • mobile system
  • mobile technology
  • mobile telecommunication system
  • mobile terminal
  • mobile tongue
  • mobile tooth
  • mobile user

  • Selected Abstracts

    Monthly Oral Ibandronate Therapy in Postmenopausal Osteoporosis: 1-Year Results From the MOBILE Study

    Paul D Miller MD
    Abstract Once-monthly (50/50, 100, and 150 mg) and daily (2.5 mg; 3-year vertebral fracture risk reduction: 52%) oral ibandronate regimens were compared in 1609 women with postmenopausal osteoporosis. At least equivalent efficacy and similar safety and tolerability were shown after 1 year. Introduction: Suboptimal adherence to daily and weekly oral bisphosphonates can potentially compromise therapeutic outcomes in postmenopausal osteoporosis. Although yet to be prospectively shown in osteoporosis, evidence from randomized clinical trials in several other chronic conditions shows that reducing dosing frequency enhances therapeutic adherence. Ibandronate is a new and potent bisphosphonate with antifracture efficacy proven for daily administration and also intermittent administration with a dose-free interval of >2 months. This report presents comparative data on the efficacy and safety of monthly and daily oral ibandronate regimens. Materials and Methods: MOBILE is a 2-year, randomized, double-blind, phase III, noninferiority trial. A total of 1609 women with postmenopausal osteoporosis were assigned to one of four oral ibandronate regimens: 2.5 mg daily, 50 mg/50 mg monthly (single doses, consecutive days), 100 mg monthly, or 150 mg monthly. Results: After 1 year, lumbar spine BMD increased by 3.9%, 4.3%, 4.1%, and 4.9% in the 2.5, 50 /50, 100, and 150 mg arms, respectively. All monthly regimens were proven noninferior, and the 150 mg regimen superior, to the daily regimen. All monthly regimens produced similar hip BMD gains, which were larger than those with the daily regimen. All regimens similarly decreased serum levels of C-telopeptide, a biochemical marker of bone resorption. Compared with the daily regimen, a significantly larger proportion of women receiving the 100 and 150 mg monthly regimens achieved predefined threshold levels for percent change from baseline in lumbar spine (6%) or total hip BMD (3%). All regimens were similarly well tolerated. Conclusions: Monthly ibandronate is at least as effective and well tolerated as the currently approved daily ibandronate regimen in postmenopausal osteoporosis. [source]

    Validated simulation of kinematics and dynamics of multibody systems using interval and Taylor model based methods

    Ekaterina Auer
    In this paper, we present an integrated environment for validated modeling and simulation of kinematics and dynamics of various classes of mechanical systems SMARTMOBILE (Simulation and Modeling of dynAmics in MOBILE: Reliable and Template,based) built on top of the non-validated tool MOBILE. We outline the main features of SMARTMOBILE and its applicability area. The functionality of the new tool and the importance of the application of validated techniques are demonstrated. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Solid-State NMR Investigations of the Unusual Effects Resulting from the Nanoconfinement of Water within Amphiphilic Crosslinked Polymer Networks

    Ryutaro Ohashi
    Abstract Two types of solid-state 19F NMR spectroscopy experiments are used to characterize phase-separated hyperbranched fluoropolymer,poly(ethylene glycol) (HBFP,PEG) crosslinked networks. Mobile (soft) domains are detected in the HBFP phase by a rotor-synchronized Hahn echo under magic-angle spinning conditions, and rigid (hard) domains by a solid echo with no magic-angle spinning. The mobility of chains is detected in the PEG phase by 1H,,,13C cross-polarization transfers with 1H spin-lock filters with and without magic-angle spinning. The interface between HBFP and PEG phases is detected by a third experiment, which utilized a 19F,,,1H,(spin diffusion),1H,,,13C double transfer with 13C solid-echo detection. The results of these experiments show that composition-dependent PEG inclusions in the HBFP glass rigidify on hydration, consistent with an increase in macroscopic tensile strength. [source]

    Brief Communications: An Analysis of Migraine Triggers in a Clinic-Based Population

    HEADACHE, Issue 8 2010
    Diane Andress-Rothrock MS
    Background., Many migraineurs report attack "triggers," but relatively few published data exist regarding the relative prevalences of individual triggers, variations related to gender, duration of migraine or migraine subtype, or the existence of any regional variations in the prevalences and distributions of triggers. Objective., We sought to determine the prevalence and types of migraine triggers in our clinic population, to determine what influence gender, migraine subtype, or duration of migraine might have on the prevalences and types of triggers reported and to compare our findings with data derived from surveys we previously had conducted involving 2 clinic-based populations and 1 general population sample from other regions of the USA. Methods., We evaluated 200 consecutive new migraine patients referred to our clinic. All patients specifically were queried as to whether they had noted any of 7 specific factors to serve consistently as migraine attack triggers and additionally were surveyed as to whether they might have "other" triggers not listed on the intake questionnaire. Among the other data collected and analyzed were age, gender, age at time of migraine onset, and migraine subtype (ie, episodic vs chronic). Actively cycling females who reported menses as a trigger were questioned as to whether their menstrual migraine (MM) attacks differed from their non-menstrual migraines and, if so, how they differed. Results., One hundred and eighty-two patients (91%) reported at least 1 migraine trigger, and 165 (82.5%) reported multiple triggers. The most common trigger reported (59%) was "emotional stress," followed by "too much or little sleep" (53.5%), "odors" (46.5%), and "missing meals" (39%). Females or subjects of either gender with chronic migraine were no more likely than males or subjects with episodic migraine to report triggers or multiple triggers. Similarly, longer exposure to migraine did not correlate with a higher likelihood of reporting a trigger or multiple triggers. Fifty-three (62%) of 85 actively cycling females reported menses as a trigger, and of the 51 with menstrually related migraine, 34 (67%) reported their MM to be more severe, more refractory to symptomatic therapy or of longer duration than their non-menstrual attacks; 13 (24.5%) of the 53 women with apparent MM reported their MM to be at least occasionally manifested as status migrainosus. The prevalence and type of triggers reported by this predominantly white female population were similar to those reported by clinic-based populations in San Diego, California and Mobile, Alabama, and in a population-based sample of Hispanics in San Diego County. Conclusions., A large majority of migraineurs report migraine attack triggers, and the triggers most commonly reported include emotional stress, a disrupted sleep pattern, and various odors. These findings do not appear to vary according to geographic region or race/ethnicity. Among the triggers, MM appears inclined to provoke headache that is more severe, less amenable to treatment, or longer in duration than headaches that occur at other times during the cycle. (Headache 2010;50:1366-1370) [source]

    "Without Hysteria or Unnecessary Disturbance": Desegregation at Spring Hill College, Mobile, Alabama, 1948,1954

    Charles S. Padgett
    First page of article [source]

    Phylogeography of the northern hogsucker, Hypentelium nigricans (Teleostei: Cypriniformes): genetic evidence for the existence of the ancient Teays River

    Peter B. Berendzen
    Abstract Aim, To assess the roles of dispersal and vicariance in shaping the present distribution and diversity within Hypentelium nigricans, the northern hogsucker (Teleostei: Cypriniformes). Location, Eastern United States. Methods, Parsimony analyses, Bayesian analyses, pairwise genetic divergence and mismatch plots are used to examine patterns of genetic variation across H. nigricans. Results, Species relationships within the genus Hypentelium were consistent with previous hypotheses. However, relationships between haplotypes within H. nigricans revealed two deeply divergent groups, a clade containing haplotypes from the New and Roanoke rivers (Atlantic Slope) plus Interior Highlands and upper Mississippi River and a clade containing haplotypes from the Eastern Highlands, previously glaciated regions of the Ohio and Wabash rivers, and the Amite and Homochitto rivers of south-western Mississippi. Main conclusions, The phylogenetic history of Hypentelium was shaped by old vicariant events associated with erosion of the Blue Ridge and separation of the Mobile and Mississippi river basins. Within H. nigricans two clades existed prior to the Pleistocene; a widespread clade in the pre-glacial Teays-Mississippi River system and a clade in Cumberland and Tennessee rivers. Pleistocene events fragmented the Teays-Mississippi fauna. Following the retreat of the glaciers H. nigricans dispersed northward into previously glaciated regions. These patterns are replicated in other clades of fishes and are consistent with some of the predictions of Mayden's (Systematic Zoology, 37, 329, 1988) pre-Pleistocene vicariance hypothesis. [source]

    Utility of Noninvasive, Mobile, Continuous Outpatient Rhythm Monitoring to Diagnose Seizure-Related Arrhythmias

    The identification of patients with a diagnosis of seizure disorder who are also at risk for clinically significant bradycardia and/or tachycardia may require long-term cardiac rhythm monitoring. Noninvasive, continuous, outpatient cardiac rhythm monitoring may be useful for such clinical scenarios. The study group consisted of two male patients with a history of seizure disorder involving loss of consciousness. Clinical data and results of electrocardiography, echocardiography, electroencephelography, and continuous, mobile, outpatient cardiac rhythm monitoring are described. In the first patient, while cardiac bradyarrhythmias were secondary to seizures, sinus arrest most likely complicated the episodes by leading to more prolonged states of unconsciousness. In the second patient, permanent pacemaker implantation for AV block averted all clinical events previously attributed to seizures. Despite the different causal relationships between seizures and bradyarrhythmias in these two patients, mobile, cardiac outpatient telemetry was successful in diagnosing the contribution of cardiac dysrhythmia, leading to permanent pacemaker implantation. A diagnostic strategy that incorporates mobile, noninvasive, continuous, outpatient cardiac rhythm monitoring can effectively be utilized to diagnose significant seizure-related arrhythmias. [source]

    Maximum-Likelihood Approach to Single-Molecule Polarization Modulation Analysis

    CHEMPHYSCHEM, Issue 9 2003
    Kenneth D. Osborn
    Mobile or not mobile? Polarization modulation has been used to probe single-molecule dynamic heterogeneity of dye molecules that are either surface-bound or incorporated in the biological system calmodulin,plasma membrane calcium ATPase. A maximum-likelihood approach was applied to determine modulation depth and phase shift of the fluorescence trajectories (see picture), which give a measure of the orientational mobility of the molecules. [source]

    How Mobile Are Resources in Chinese Agriculture?, Implications for China's Agricultural Trade Policy

    Funing Zhong
    Abstract Agricultural trade policy in China has been the subject of heated discussion since China's accession to the WTO. Studies have been carried out and propositions put forth regarding comparative advantage, food security, development of the industry, and farmers' income. In this paper, we attempt to provide an analysis from another important perspective: resource mobility, which is an essential assumption in free trade theory. By examining the mobility of different production resources in Chinese agriculture, namely natural resources, capital inputs, human resources and institutional arrangements, we found that for most production resources in Chinese agriculture, mobility is low. The results have significant policy implications in two respects: first, protective measures in the transitional period for certain crops in certain areas in China are legitimate and necessary to ensure social stability; and second, policy instruments to improve resource mobility in Chinese agricultural should be explored and implemented to realize more trade benefit in the future. (Edited by Xinyu Fan) [source]

    A survey of mobile and wireless technologies for augmented reality systems

    George Papagiannakis
    Abstract Recent advances in hardware and software for mobile computing have enabled a new breed of mobile augmented reality (AR) systems and applications. A new breed of computing called ,augmented ubiquitous computing' has resulted from the convergence of wearable computing, wireless networking, and mobile AR interfaces. In this paper, we provide a survey of different mobile and wireless technologies and how they have impact AR. Our goal is to place them into different categories so that it becomes easier to understand the state of art and to help identify new directions of research. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Augmented reality agents for user interface adaptation

    István Barakonyi
    Abstract Most augmented reality (AR) applications are primarily concerned with letting a user browse a 3D virtual world registered with the real world. More advanced AR interfaces let the user interact with the mixed environment, but the virtual part is typically rather finite and deterministic. In contrast, autonomous behavior is often desirable in ubiquitous computing (Ubicomp), which requires the computers embedded into the environment to adapt to context and situation without explicit user intervention. We present an AR framework that is enhanced by typical Ubicomp features by dynamically and proactively exploiting previously unknown applications and hardware devices, and adapting the appearance of the user interface to persistently stored and accumulated user preferences. Our framework explores proactive computing, multi-user interface adaptation, and user interface migration. We employ mobile and autonomous agents embodied by real and virtual objects as an interface and interaction metaphor, where agent bodies are able to opportunistically migrate between multiple AR applications and computing platforms to best match the needs of the current application context. We present two pilot applications to illustrate design concepts. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Studies on dentin grafts to bone defects in rabbit tibia and mandible; development of an experimental model

    Lars Andersson
    This property may possibly be used as an alternative or supplement to bone grafting to defective areas after trauma prior to treatment with osseointegrated implants. Hence, the objective of this study was to investigate if dentin can be used as a graft in bone defects in an experimental rabbit model. Materials and Methods:, Eight New Zealand White Rabbits were used to prepare bone cavities either in the angle of the mandible or tibia. Six of the eight tibial and six of the eight mandibular bone defects were filled with dentin blocks from human premolars which were extracted for orthodontic treatment. Two mandibular and two tibial bone cavities were used as controls and all the rabbits were sacrificed after 3 months. Radiographic and histological examinations were performed. Results:, There was a difference in healing pattern between the mandibular and tibial defects. In the mandible, the dentin blocks were resorbed to a larger extent and more often surrounded by fibrous tissue, probably due to the fact that the dentin blocks were mobile because of the thin mandibles and muscular activity in that area. Only some dentin blocks were ankylosed with the mandibular bone. In the tibia however, all dentin blocks were fused to bone over a large area. Osseous replacement resorption was seen. In control cavities, bone formation was seen but was never complete. No signs of inflammatory changes were seen in any fused grafts. Conclusions:, Dentin grafts have a potential to be incorporated in bone without inflammation and can be used as bone inducer and later replaced by bone. Thus, rabbit tibia served as a better model for further studies of this phenomenon when compared to the mandible. [source]

    An unusual lateral luxation of an upper incisor owing to long-term boxing without protection

    Ron Bechor
    The tooth displacement gradually worsened over several months because the boxer received repeated blows to the head without using a mouthguard. Being a chronic dental trauma, rather than an acute lateral luxation, this case had several unique features: the labial plate of the alveolar bone was penetrated, the root apex was free in the vestibulum, the tooth was mobile (second degree) and radiographs revealed bone resorption. This case emphasized the need for a mouthguard to be used even with amateur boxing. The dental practitioner should educate his sportsmen,patients of the risk of sport-related dental trauma and the benefit of a mouthguard. [source]

    Gauging the societal impacts of natural disasters using a capability approach

    DISASTERS, Issue 3 2010
    Paolo Gardoni
    There is a widely acknowledged need for a single composite index that provides a comprehensive picture of the societal impact of disasters. A composite index combines and logically organizes important information policy-makers need to allocate resources for the recovery from natural disasters; it can also inform hazard mitigation strategies. This paper develops a Disaster Impact Index (DII) to gauge the societal impact of disasters on the basis of the changes in individuals' capabilities. The DII can be interpreted as the disaster impact per capita. Capabilities are dimensions of individual well-being and refer to the genuine opportunities individuals have to achieve valuable states and activities (such as being adequately nourished or being mobile). After discussing the steps required to construct the DII, this article computes and compares the DIIs for two earthquakes of similar magnitude in two societies at different levels of development and of two disasters (earthquake and wind storm) in the same society. [source]

    Two new iniopterygians (Chondrichthyes) from the Mississippian (Serpukhovian) Bear Gulch Limestone of Montana with evidence of a new form of chondrichthyan neurocranium

    ACTA ZOOLOGICA, Issue 2009
    Eileen D. Grogan
    Abstract The Iniopterygia are Palaeozoic chondrichthyans whose morphology and relationships are poorly understood. The morphology of two new taxa of Iniopterygidae, Rainerichthys zangerli and Papilionichthys stahlae, from the Upper Mississippian of Montana is now described. They exhibit the iniopterygian synapomorphy of dorsolaterally placed pectoral fins. They also display a laterally compressed head and body, a homocercal tail, and a single aspinous dorsal fin originating at approximately mid-body. These taxa differ in upper dental elements, bony cranial plates, body squamation, buccopharyngeal denticles, cranial linking cartilages, palatoquadrate shape, pterygoid articulation, pectoral axis and pectoral girdle shape, and in the robustness of branchial and suprascapular cartilages. The neurocranium is unique among known chondrichthyans in presenting anterior ethmosphenoid and posterior otico-occipital units separated by an intracranial joint. A complete otico-occipital fissure is found posteriorly. One to two pairs of upper parasymphysial whorls and one median lower premandibular symphysial whorl are present. Symphysial whorls were mobile and the cranial complex appears to have been kinetic. Cladistic assessment places these new taxa as basal chondrichthyans below the divergence of the Elasmobranchii and the Euchondrocephali. The range of morphology within known iniopterygians supports rapid diversification and niche specialization in this group of atypical chondrichthyans. [source]

    Palaeomonsoon variability in the southern fringe of the Badain Jaran Desert, China, since 130 ka BP

    Quanzhou Gao
    Abstract Taking the Chagelebulu Stratigraphic Profile as a typical example, a comprehensive study has been conducted to elucidate the palaeoclimatic and geomorphic evolution patterns in the southern fringe of the Badain Jaran Desert, which were found to be complex and polycyclic in the past 130 ka. However, the fluctuating magnitude is not as remarkable as that in the eastern China sandy region. The shift in climate from interglacial to glacial and the uplift process of the Qinghai,Xizang Plateau are the two leading forces driving the evolution of the climate and desert landforms in this area. Seventeen cycles of cold, dry and warm, humid climatic stages were recognized in the Upper Pleistocene Series of the profile. The sharp uplift of the Qinghai,Xizang Plateau superimposed a cool and arid climatic trend in this area. As a result of the climatic changes, the desert in this area has undergone multiple stages of expansion and contraction since 130 ka bp. The middle Holocene Epoch and the early stage of the Late Pleistocene Period were the main periods when the sand dunes became stabilized, and the early and late phases of the Holocene Epoch and late phase of the Pleistocene Epoch were the main periods when the previously stabilized sand dunes became mobile. The late phase of the Pleistocene Epoch was the most mobile stage, when the aeolian sand activities formed the essential geomorphic pattern of the Badain Jaran Desert. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Phylogenetic analysis of the pearlfish tribe Carapini (Pisces: Carapidae)

    ACTA ZOOLOGICA, Issue 4 2000
    E. Parmentier
    Abstract Fishes of the tribe Carapini (Encheliophis and Carapus) share a noteworthy peculiarity: they shelter in holothurian echinoderms or bivalve hosts. Some species are considered parasitic, others commensal. This study focuses on the phylogeny of the tribe, using two other Carapidae species as an outgroup (Snyderidia canina and Onuxodon fowleri). Insofar as possible, the selected anatomical and behavioural characters where chosen in an ecomorphological perspective, as features that could be responses to various lifestyle-related constraints. Our character selection also took into account the fact that some features are (presumably) linked. Such features were grouped together as a single trait to avoid their overvaluation. This methodology enabled commensals to be separated from parasites, the former belonging to Carapus and the latter to Encheliophis. Carapus species reflect in their morphology the constraints imposed by a diet of hard, mobile, elusive prey, showing predator-type features: a strong dentition, a wide mouth opening, a robust food intake apparatus. On the other hand, the endoparasitic Encheliophis species show a generally weaker buccal apparatus and narrow mouth opening, in relation to the different constraints of their lifestyle where the diet constraints are less pronounced: they eat body parts of their host. Changes in both generic diagnoses are proposed and three species are transferred from Encheliophis to Carapus. [source]

    Lesions of the Mitral Valve as a Cause of Central Retinal Artery Occlusion: Presentation and Discussion of Two Cases

    ECHOCARDIOGRAPHY, Issue 1 2010
    Maryam Ayati M.D.
    We present two cases of mitral valve lesions that manifested with unilateral blindness caused by central retinal artery occlusion (CRAO): Case 1. A 68-year-old woman was admitted to our clinic for sudden blindness. Retinal artery angiogram showed CRAO. Transthoracic and transesophageal echocardiography (TEE) documented a mass attached to the ventricular side of the posterior mitral leaflet, which at pathology was identified as a blood cyst. Case 2. A 67-year-old man was admitted for a sudden unilateral painless loss of vision. Retinal angiogram documented CRAO, and TEE showed a highly mobile, spherical, lesion on the atrial side of anterior mitral leaflet. In this case, the pathological finding was a degenerated calcified thrombosis. We report on two cases of very rare abnormalities of the mitral valve presenting with a very rare embolic complication, i.e., CRAO. Like for cryptogenic stroke, transesophageal echocardiography plays a central role in the diagnosis of cardiogenic embolic sources. (Echocardiography 2010;27:E1-E3) [source]

    Evaluation and Management of Left Atrial Lymphoma Guided by Transesophageal Echocardiography

    ECHOCARDIOGRAPHY, Issue 6 2003
    Howard J. Willens
    A highly mobile left atrial mass was detected by transesophageal echocardiography in a patient with mediastinal lymphoma. Transesophageal echocardiography also demonstrated resolution of the mass following chemotherapy. (ECHOCARDIOGRAPHY, Volume 20, August 2003) [source]

    Health food versus fast food: the effects of prey quality and mobility on prey selection by a generalist predator and indirect interactions among prey species

    Micky D. Eubanks
    Summary 1. In order to understand the relative importance of prey quality and mobility in indirect interactions among alternative prey that are mediated by a shared natural enemy, the nutritional quality of two common prey for a generalist insect predator along with the predator's relative preference for these prey was determined. 2. Eggs of the corn earworm Helicoverpa zea (Lepidoptera: Noctuidae) were nutritionally superior to pea aphids Acyrthosiphum pisum (Homoptera: Aphididae) as prey for big-eyed bugs Geocoris punctipes (Heteroptera: Geocoridae). Big-eyed bugs survived four times as long when fed corn earworm eggs than when fed pea aphids. Furthermore, only big-eyed bugs fed corn earworm eggs completed development and reached adulthood. 3. In two separate choice experiments, however, big-eyed bugs consistently attacked the nutritionally inferior prey, pea aphids, more frequently than the nutritionally superior prey, corn earworm eggs. 4. Prey mobility, not prey nutritional quality, seems to be the most important criterion used by big-eyed bugs to select prey. Big-eyed bugs attacked mobile aphids preferentially when given a choice between mobile and immobilised aphids. 5. Prey behaviour also mediated indirect interactions between these two prey species. The presence of mobile pea aphids as alternative prey benefited corn earworms indirectly by reducing the consumption of corn earworm eggs by big-eyed bugs. The presence of immobilised pea aphids, however, did not benefit corn earworms indirectly because the consumption of corn earworm eggs by big-eyed bugs was not reduced when they were present. 6. These results suggest that the prey preferences of generalist insect predators mediate indirect interactions among prey species and ultimately affect the population dynamics of the predator and prey species. Understanding the prey preferences of generalist insect predators is essential to predict accurately the efficacy of these insects as biological control agents. [source]

    The role of larval aggression and mobility in the transition between solitary and gregarious development in parasitoid wasps

    ECOLOGY LETTERS, Issue 6 2000
    G. Boivin
    Models explaining the appearance of gregariousness in insect parasitoids assume the presence of a tolerance gene that enables nonsiblicidal behaviour in gregarious larvae. Under this assumption, nontolerant individuals should attack and kill tolerant individuals when sharing a host, making this behaviour susceptible to invasion by nontolerant individuals. We propose an alternative hypothesis where gregarious larvae retain their aggressiveness but are less mobile. We tested this hypothesis with two sympatric and congeneric species of Mymaridae, Anaphes victus and Anaphes listronoti, respectively, solitary and gregarious egg parasitoids of a Curculionidae, Listronotus oregonensis. Results obtained in competition experiments and from direct observation of movement in mymariform larvae of both species support the reduced mobility hypothesis. By being immobile while retaining their fighting capacity, A. listronoti mymariform larvae appear to optimize host utilization through gregarious development, but can still defend themselves against sympatric aggressive species. [source]

    Assessment of residency and movement of the endangered bullhead (Cottus gobio) in two Flemish rivers

    G. Knaepkens
    Abstract,,, Residency and movement of bullheads (Cottus gobio) were assessed by mark-recapture from November 2001 to June 2002 in two Flemish rivers [Steenputbeek (SPB), Laarse Beek (LB)]. Although the majority of the recaptured bullheads (SPB: 66%; LB: 55%) was found in their initial tagging site before the spawning season, some fish had covered distances between 10,100 m (mean: 17 ± 2 m) and 10,70 m (mean: 18 ± 7 m), respectively. During the spawning season, the proportion of fish that moved (SPB: 58%; LB: 75%) and the distances travelled (SPB: between 10 and 90 m, mean 26 ± 3 m; LB: between 30 and 260 m, mean 133 ± 3 m) were significantly larger. In addition, analysis of individual movement behaviour of multiple recaptured bullheads showed that some fish were either always resident or mobile, while others switched between both behaviours. In general, our results suggest that not all bullheads exhibit sedentary behaviour but that the populations under study consist of both stationary and mobile individuals. Resumen 1. Desde Noviembre del año 2001 hasta Junio del 2002, evaluamos la residencia y los movimientos de Cottus gobio a través de técnicas de marcado-recaptura en dos ríos flamencos: Steenputbeek (SPB) y Laarse Beek (LB). Aunque antes de la estación reproductiva, la mayoría de los individuos re-capturados (66% en SPB y 55% en LB) fueron encontrados en las mismas localidades de marcado, algunos peces habían cubierto distancias entre 10 y 100 metros (media = 17.2 ± 2 m) y entre 10 y 70 m (media = 18.0 ± 7 m) en SPB y LB, respectivamente. Durante la estación reproductiva, tanto la proporción de individuos que se movieron (58% en SPB y 75% en LB), como las distancias recorridas fueron significativamente mayores: en SPB, entre 10 y 90 m, media = 26.0 ± 3 m y en LB entre 30 y 260 m, media = 133.0 ± 3 m. 2. Análisis del comportamiento entre múltiples individuos mostró que algunos individuos fueron o residentes o móviles mientras que otros individuos cambiaron entre ambos comportamientos. En general, nuestros resultados sugieren que no todos los individuos muestran comportamiento sedentario sino que la población incluye individuos estacionarios y móviles. [source]

    Factor mobility and fiscal policy in the EU: policy issues and analytical approaches

    ECONOMIC POLICY, Issue 31 2000
    David E. Wildasin
    Increased integration of labour and capital markets creates significant challenges for the welfare states of modern Europe. Taxation of capital and labour that finances extensive programmes of cash and in-kind redistribution creates incentives for capital owners and workers to locate in regions where they obtain favourable fiscal treatment. Competition among countries for mobile resources constrains their ability to alter the distribution of income and may lead to reductions in the size and scope of redistributive policies. Mobility of labour and capital is imperfect, however. Recent trends indicate that labour and capital are neither perfectly mobile nor perfectly immobile, but rather adjust gradually to market conditions and economic policies. This paper presents an explicitly dynamic analysis showing that governments can achieve some redistribution when it is costly for factors of production to relocate. As the costs of factor mobility fall, however, the effectiveness of redistributive policies is more limited, and governments have weaker incentives to pursue them. Liberalized immigration policies, EU enlargement, and other steps that promote integration of the factors markets of Western Europe with those of surrounding regions thus present a challenge to policy-makers if they also wish to maintain fiscal systems with extensive redistribution. [source]

    Labour market implications of EU product market integration

    ECONOMIC POLICY, Issue 30 2000
    Torben M. Andersen
    European labour markets are in a state of flux due to the changing market situation induced by international integration. This process affects wage formation through more fierce product market competition and increased mobility of jobs. This development is by some observers taken to enforce labour market flexibility, while for others it signals an erosion of social standards and in turn possibly the welfare society. Since labour is not very mobile in Europe, the effects of international integration on labour markets are mostly indirect via product market integration. We review the channels through which product market integration affects labour markets and perform an empirical analysis of the convergence and interdependencies in wage formation among EU countries. We find that integration is changing labour market structures and inducing wage convergences as well as stronger wage interdependencies, but it is a gradual process. Moreover, the present study does not support the view that international integration will lead to a ,race to the bottom' and rapidly erode domestic labour markets standards, nor that it will relieve politicians of the need to consider labour market reforms to improve labour market performance. [source]

    Bog Iron Ores and their Potential Role in Arsenic Dynamics: An Overview and a "Paleo Example"

    A. Banning
    Abstract Bog iron ores (BIOs), i.e. terrestrial accumulations of iron (Fe) minerals forming within the zone of groundwater oscillation, have been described in several regions in Germany and other countries. Since BIOs are composed of a variety of Fe minerals, primarily amorphous Fe hydroxides, they are likely to have an influence on the arsenic (As) dynamics of an area, as these minerals represent important natural As sources and sinks. In this study, mineralogical research results (XRD, microscopy) of altered BIOs of Tertiary age ("paleo" BIOs or PBIOs), occurring within Cretaceous sands in an area of North Rhine-Westphalia, are briefly presented. Genesis and mineralogical evolution of the categorized five different types of PBIOs, along with hydrogeochemical data from the literature, are discussed and compared to studies describing Holocene BIOs from other areas. In doing so, striking similarities (depositional environment, substratum, Fe source and its transport, geochemical evolution, and mineralogy) became evident. Differences in mineralogical and chemical composition can be attributed to the longer period of oxidation that the PBIOs have undergone (Fe hydroxide "aging"). This process is still ongoing (most of the groundwaters in the area plot in the goethite stability field) and leads to a higher stability of the Fe phases and thus, a stronger As retention. The known impact of the PBIOs on the As budget of the study area (they represent the source for elevated As concentrations in soils) can be transferred to more recent environments fostering BIO formation. These are likely to be even more important As sinks , and sources , as they contain higher Fe concentrations, higher shares of potentially mobile As and highly variable redox conditions which might lead to an As output from the BIOs into groundwater, soils and plants. Therefore, BIOs and their potential role in As behaviour are not only of scientific, but also of public interest. [source]

    Dissipation kinetics and mobility of chlortetracycline, tylosin, and monensin in an agricultural soil in Northumberland County, Ontario, Canada

    Jules C. Carlson
    Abstract A robust high-throughput method was refined to extract three growth-promoting antibiotics, tylosin (TYL), chlortetracycline (CTC), and monensin (MON), from soil. Analysis was performed by electrospray liquid chromatography tandem mass spectrometry. Soil dissipation rate studies were performed in a farm field soil for antibiotics applied with and without manure. Tylosin, CTC, and MON followed first-order dissipation kinetics with half-lives of 4.5, 24, and 3.3 d, respectively, with the addition of manure and 6.1, 21, and 3.8 d, respectively, without manure. Manure application significantly increased TYL dissipation rate, perhaps because of the introduced microbial flora, but had no significant effect on CTC or MON. Monensin dissipation half-life was found to be much shorter in the field study than in a controlled laboratory study, perhaps because of differences in microbial communities. The antimicrobials were not highly mobile. Chlortetracycline was the only antibiotic detected at 25 to 35 cm depth and only up to 2% of the initial concentration in a sandy loam soil. These antibiotics are therefore expected to degrade primarily in agricultural soils before moving to greater depths or to groundwater in significant concentrations in most agricultural systems. [source]

    Control of eye orientation: where does the brain's role end and the muscle's begin?

    Dora E. Angelaki
    Abstract Our understanding of how the brain controls eye movements has benefited enormously from the comparison of neuronal activity with eye movements and the quantification of these relationships with mathematical models. Although these early studies focused on horizontal and vertical eye movements, recent behavioural and modelling studies have illustrated the importance, but also the complexity, of extending previous conclusions to the problems of controlling eye and head orientation in three dimensions (3-D). An important facet in understanding 3-D eye orientation and movement has been the discovery of mobile, soft-tissue sheaths or ,pulleys' in the orbit which might influence the pulling direction of extraocular muscles. Appropriately placed pulleys could generate the eye-position-dependent tilt of the ocular rotation axes which are characteristic for eye movements which follow Listing's law. Based on such pulley models of the oculomotor plant it has recently been proposed that a simple two-dimensional (2-D) neural controller would be sufficient to generate correct 3-D eye orientation and movement. In contrast to this apparent simplification in oculomotor control, multiple behavioural observations suggest that the visuo-motor transformations, as well as the premotor circuitry for saccades, pursuit eye movements and the vestibulo-ocular reflexes, must include a neural controller which operates in 3-D, even when considering an eye plant with pulleys. This review summarizes the most recent work and ideas on this controversy. In addition, by proposing directly testable hypotheses, we point out that, in analogy to the previously successful steps towards elucidating the neural control of horizontal eye movements, we need a quantitative characterization first of motoneuron and next of premotor neuron properties in 3-D before we can succeed in gaining further insight into the neural control of 3-D motor behaviours. [source]

    Percolation characteristics of a water-repellent sandy forest soil

    G. Wessolek
    Summary In a tracer experiment TDR transect measurements were made to study percolation behaviour in a 120-year-old pine stand (Pinus sylvestris) on a water-repellent sandy soil (Haplic Arenosol). The experiment (with potassium iodide) showed an 80% labelling of the total flow in organic layers, whereas the area of transport in the mineral soil was sharply reduced to 12,30%. The average diameters of these preferential flow paths were about 8,15 cm. The TDR measurements indicate a homogeneous flow only for a short period from February until April. At this time of the year preferential flow is insignificant, because the soil is at approximately field capacity and not repellent to water. During summer (May to September) the soil dries out, and most precipitation results in preferential flow during this period. For any daily rainfall exceeding 10 mm, water infiltrates down to 1 m depth in the soil, which nevertheless, is still within the root zone. This kind of deep percolation results in the subsoil's wetting to field capacity (pF 1.8) earlier than the topsoil. A one-dimensional numerical model (SWAP) was used to simulate mean water balance with hydraulic functions with and without a water-repellency term. From the results of our tracer experiment we showed that the de-watering process in spring could be simulated well using the traditional piston flow concept, while the rewetting behaviour could be described more realistically using the mobile,immobile concept for water repellency. [source]

    Fate of airborne metal pollution in soils as related to agricultural management.


    Summary The fate of airborne metal pollutants in soils is still relatively unknown. We studied the incorporation of such airborne metal pollution in two soils under long-term permanent pasture (PP) and conventional arable land (CA). Both soils were located at an almost equal distance from a former zinc smelter complex and developed under comparable pedogenetic conditions. Profiles of total concentrations of Zn, chosen as a mobile, and Pb as a little- or non-mobile element, were examined and compared with macro- and micromorphological soil characteristics (soil colour, biological activity). The two soils showed different profiles of total Zn and Pb concentrations, with a marked decrease of concentrations of both elements under the plough layer in CA, whereas the decrease was more progressive in PP. However, the stocks of Zn and Pb for the 1-m soil profiles of CA and PP were comparable. Correlation of Zn and Pb concentration at different depths with total Fe contents and comparison with estimated data for the local geochemical background (LGCB), suggests transport of Zn from the surface to depth in CA and PP, and Pb movement in PP. In CA, 53% of Zn and 92.5% of Pb stocks derived from airborne metal pollution were located at depths < 26 cm. In PP, only 40% of Zn and 82% of Pb, derived from airborne pollution, were found in the A11 and A12 horizons (< 26 cm), the remaining 18% of the Pb stock being incorporated until 50 cm depth; one-third of total Zn stock ascribed to airborne pollution was found at depths > 50 cm. Studies of the composition of gravitational water collected in soils from the same study area suggest two mechanisms for metal movement. First, mobile metal ions (Zn2+) move in the soil solution and are intercepted by iron-clay complexes in deeper soil horizons. Second, observed only in PP, simultaneous movement of Zn and Pb is ascribed to bioturbation by earthworms. [source]

    Lime and cow slurry application temporarily increases organic phosphorus mobility in an acid soil

    P. N. C. MurphyArticle first published online: 13 OCT 200
    Summary Phosphorus loss from agricultural soils to water is recognized as a major contributor to eutrophication of surface water bodies. There is much evidence to suggest that liming, a common agricultural practice, may decrease the risk of P loss by decreasing P solubility. An unsaturated leaching column experiment, with treatments of control and two lime rates, was carried out to investigate the effects of liming on P mobility in a low-P acid Irish soil, which was sieved and then packed in columns. Phosphorus was applied at the soil surface in the form of KH2PO4 in solution or as cow slurry. Soil solution was sampled at time intervals over depth and analysed for P fractions. Organic P (OP) was the dominant form of P mobile in soil solution. Liming increased OP mobility, probably through increased dispersion of OP with increased pH. Slurry application also increased OP mobility. Results indicated the potential for OP loss following heavy (100 m,3 ha,1) cow slurry application, even from low-P soils, and suggested that liming may increase this risk. Reactive P (RP) was sorbed strongly and rapidly by the soil and did not move substantially below 5 cm depth. As a result, Olsen-P values in the top 2 cm were greatly increased, which indicates an increased risk of RP loss in overland flow. Lime showed little potential as a soil amendment to reduce the risk of P loss. [source]