Small Area (small + area)

Distribution by Scientific Domains
Distribution within Life Sciences

Kinds of Small Area

  • very small area


  • Selected Abstracts


    Glacial refugia for summer-green trees in Europe and south-west Asia as proposed by ECHAM3 time-slice atmospheric model simulations

    JOURNAL OF BIOGEOGRAPHY, Issue 12 2007
    Suzanne A. G. Leroy
    Abstract Aim, To generate maps of potential refugia for summer-green trees during the Last Glacial Maximum (LGM). Locations, Southern Europe and south-western Asia. Methods, Time-slice simulations of the atmospheric climate with the ECHAM3 model are used for the LGM. Limiting factors beyond which cool and warm groups of deciduous trees cannot grow (such as temperature in growing degree days, minimum monthly temperature and precipitation in summer) are chosen. A limited validation by fossil pollen and charcoal records from LGM sites was done. Results, Two sets of maps extending from Europe to the Caspian region for cool and warm summer-green trees are presented. Three criteria are combined using contour lines to indicate confidence levels. Small areas within the three southern peninsulas of Europe (Spain, Italy and Greece) are highlighted as possible refugia for summer-green trees. Further, areas that have remained poorly known are now proposed as refugia, including the Sakarya,Kerempe region in northern Turkey, the east coast of the Black Sea and the area south of the Caspian Sea. Main conclusions, The maps produced in this study could be used to facilitate better long-term management for the protection of European and south-western Asian biodiversity. [source]


    Continuous arterial spin labeling at the human common carotid artery: the influence of transit times

    NMR IN BIOMEDICINE, Issue 1 2005
    Toralf Mildner
    Abstract In evaluating the sensitivity of arterial spin labeling (CASL) and for quantification of perfusion, knowledge of the transit time from the labeling plane to the imaging slice is crucial. The purpose of the current study was to obtain estimates of transit times relevant under the specific experimental conditions of CASL in human subjects using a separate local labeling coil at the neck. Specifically, the post-label delay (PLD), i.e. the time between the end of the labeling period and the image acquisition, was varied either with or without additional application of crusher gradients to suppress intravascular signal contributions. The overall sensitivity change for varying the PLD between 1000 and 1700,ms was low. A tissue transit time from the neck to an axial supraventricular section through Broca's knee was obtained by fitting the PLD dependence to a two-compartment model. Averaging over subjects yielded 1930,±,110,ms for the tissue transit time, and 73,±,5,ml,min,1 100,g,1 for the cerebral blood flow. Small areas that exhibited a very high signal change upon labeling were indicative of regional variation in cerebral blood flow related to vascular anatomy. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Spatially resolved evaluation of power losses in industrial solar cells by illuminated lock-in thermography

    PROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 5 2004
    Joerg Isenberg
    Abstract The principles of a recently introduced measurement technique for power losses in solar cells, illuminated lock-in thermography (ILT), are reviewed. The main advantage of ILT over dark lock-in Thermography (DLT) is measurement under realistic operational conditions of solar cells. The main focus of this paper is to demonstrate the wide range of applications of ILT in identifying the causes of power losses in solar cells. For this purpose different evaluation methods are presented. A method for the evaluation of improvement potentials within a given cell technology is demonstrated. It is shown that different types of series resistance may be localized. Small areas of recombination losses (e.g., grain boundaries) can routinely be detected, which is not possible in dark lock-in thermography. Good correspondence with light-beam-induced current images is found. A realistic evaluation of the impact of recombination losses on solar cell performance is demonstrated on two examples. Finally, process- or treatment-induced recombination losses are investigated. In summary ILT is shown to be an extremely powerful tool in localizing, identifying and quantifying power losses of solar cells under realistic illumination conditions. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Dose per unit area , a study of elicitation of nickel allergy

    CONTACT DERMATITIS, Issue 5 2007
    Louise Arup Fischer
    Background:, Experimental sensitization depends upon the amount of allergen per unit skin area and is largely independent of the area size. Objectives:, This study aimed at testing if this also applies for elicitation of nickel allergy. Patients/methods:, 20 nickel allergic individuals were tested with a patch test and a repeated open application test (ROAT). Nickel was applied on small and large areas. The varying parameters were area, total dose and dose per unit area. Results:, In the patch test, at a low concentration [15 ,g nickel (,gNi)/cm2], there were significantly higher scores on the large area with the same dose per area as the small area. At higher concentrations of nickel, no significant differences were found. In the ROAT at low concentration (6.64 ,gNi/cm2), it was found that the latency period until a reaction appeared was significantly shorter on the large area compared to the small area. It was also found that the ROAT threshold (per application) was lower than the patch test threshold. Conclusion:, For elicitation of nickel allergy, the size of the exposed area and therefore the total amount of applied nickel, influence the elicitation reaction at some concentrations, even though the same dose per unit area is applied. [source]


    Noninvasive Lower Eyelid Blepharoplasty: A New Technique Using Nonablative Radiofrequency on Periorbital Skin

    DERMATOLOGIC SURGERY, Issue 2 2004
    Javier Ruiz-esparza MDArticle first published online: 3 FEB 200
    Background. Laxity and rhytids of the lower eyelids are common cosmetic concerns. Historically, correction has either been surgical through either transcutaneous or transconjunctival blepharoplasty or ablative through laser resurfacing or chemical peeling. Therapeutic options usually require significant postoperative healing and have the potential risk of scarring ectropion or pigmentary loss. Objective. To report the use of a new technique that uses nonablative radiofrequency (NARF) to tighten noninvasively and nonsurgically the flaccid skin of the lower eyelids by treating the periorbital area to produce cosmetic improvement. Methods. Nine patients with skin flaccidity of the lower eyelids had a single treatment session with NARF in a small area of skin in the periorbital region, specifically the zygomatic and/or temporal areas. All patients were treated with topical anesthesia only. The treatment lasted approximately 10 minutes. No postoperative care was required. Results. All of the nine patients in the study achieved cosmetic improvement of the eyelids ostensibly through skin contraction. All patients were able to return to their normal routines immediately. Although the results were gradual, patient satisfaction was remarkable. No complications were seen in this study. Conclusion. This new procedure using NARF was successful in providing a safe, noninvasive, cosmetic improvement in these patients with excessive skin laxity of the lower eyelids. Postoperative morbidity, including down time and complications, was not seen. [source]


    CO2 Laser Treatment of Epidermal Nevi: Long-Term Success

    DERMATOLOGIC SURGERY, Issue 7 2002
    Sarah Boyce MD
    background. Epidermal nevi have been notoriously difficult to treat due to their large size and often conspicuous location. Variable results have been obtained with different laser treatments, and scarring and/or incomplete removal is typical after excisional or other destructive modalities. objective. To outline the successful use of a short-pulsed CO2 laser in the long-term eradication of epidermal nevi in three patients. methods. Three females (ages 15,19) presented with extensive grouped verrucous papules and plaques on the face, trunk, and extremities. A pulsed CO2 laser was used to vaporize the lesions using a 500 mJ pulse energy, 3 mm spotsize, and 7 watts of power. results. All lesions healed without incident. No lesional recurrence was observed 10 to 13 months after treatment except in one small area on the ankle in one patient. conclusions. Carbon dioxide laser vaporization of epidermal nevi provides good clinical effect and offers unique advantages for the treatment of these lesions, including effective intraoperative hemostasis with excellent lesional visualization. It is also possible to treat widespread areas in one laser treatment session. While the results of this series clearly show the benefit of CO2 laser treatment, epidermal nevi may not always respond so favorably, due in part to the variability in their depths of involvement. [source]


    Lower esophageal palisade vessels and the definition of Barrett's esophagus

    DISEASES OF THE ESOPHAGUS, Issue 7 2008
    K. Ogiya
    SUMMARY., The designated area of the columnar-lined esophagus (CLE) is anatomically defined by the distal limit of the lower esophageal palisade vessels (LEPV) and the term ,Barrett's esophagus' is equally used along with the name CLE in Japan. The aim of this study was to investigate the actual prevalence of CLE based on the Japanese criteria and to evaluate the criteria per se. A total of 42 esophagi consecutively resected at this institute were included. All subjects underwent a surgical resection for squamous cell carcinoma of the esophagus. The position of the LEPV, squamocolumnar junction, the prevalence of CLE and intestinal metaplasia were investigated both pre- and postoperatively. Preoperative endoscopy revealed CLE based on the Japanese criteria in half of all patients. In the resected specimens the distal limit of LEPV was lower than the squamocolumnar junction in 95.2%. In other words, almost all cases had CLE (equivalent to Barrett's mucosa in Japanese criteria). However, most of the CLE areas were very short and their average maximum length was only about 5 mm. In addition, no intestinal metaplasia was observed in any of the CLE cases. Almost all individuals might therefore be diagnosed to have CLE or Barrett's mucosa based on precise endoscopic observations in Japan. The CLE located in a small area, e.g. less than 5 mm, defined according to the LEPV criteria without any other factor concerning typical Barrett's esophagus such as signs of gastroesophageal reflux should therefore be excluded from consideration as a high-risk mucosa. [source]


    When fish meet fish as determined by physiological sensors

    ECOLOGY OF FRESHWATER FISH, Issue 4 2009
    O. Slavík
    Abstract,,, Electromyogram (EMG) biotelemetry allows a description of the spatial distribution of fish together with a simultaneous measurement of individual energy consumption. Using this technique, we observed behaviour of the largest European freshwater predator, Silurus glanis, in the Elbe River, Central Europe. In total, 52 diurnal cycles and 1248 individual fish positions were recorded with 12,480 EMG records during the period from March to May 2006; 1013 fish positions with 10,130 EMG records were further used for statistical analyses. Energy consumption increased with decreasing mutual distance between specimens, an effect that occurred predominantly when both of them were simultaneously in overlapping preferred areas [core areas (CAs)] appointed within their home ranges (HRs). Furthermore, with increasing energy consumption individual's movement range in longitudinal and lateral profiles decreased; i.e., the fish were positioned within a small area. When the CAs of tested individuals did not overlap, no relationship between EMG signals and mutual distance of conspecifics was found. Our results indicate that movement activity and also social behaviour can be determined with physiological sensors. [source]


    A comparison of five fMRI protocols for mapping speech comprehension systems

    EPILEPSIA, Issue 12 2008
    Jeffrey R. Binder
    Summary Aims:, Many fMRI protocols for localizing speech comprehension have been described, but there has been little quantitative comparison of these methods. We compared five such protocols in terms of areas activated, extent of activation, and lateralization. Methods:, fMRI BOLD signals were measured in 26 healthy adults during passive listening and active tasks using words and tones. Contrasts were designed to identify speech perception and semantic processing systems. Activation extent and lateralization were quantified by counting activated voxels in each hemisphere for each participant. Results:, Passive listening to words produced bilateral superior temporal activation. After controlling for prelinguistic auditory processing, only a small area in the left superior temporal sulcus responded selectively to speech. Active tasks engaged an extensive, bilateral attention, and executive processing network. Optimal results (consistent activation and strongly lateralized pattern) were obtained by contrasting an active semantic decision task with a tone decision task. There was striking similarity between the network of brain regions activated by the semantic task and the network of brain regions that showed task-induced deactivation, suggesting that semantic processing occurs during the resting state. Conclusions:, fMRI protocols for mapping speech comprehension systems differ dramatically in pattern, extent, and lateralization of activation. Brain regions involved in semantic processing were identified only when an active, nonlinguistic task was used as a baseline, supporting the notion that semantic processing occurs whenever attentional resources are not controlled. Identification of these lexical-semantic regions is particularly important for predicting language outcome in patients undergoing temporal lobe surgery. [source]


    New taxa of Allium L. subg.

    FEDDES REPERTORIUM, Issue 7-8 2008
    Allium (Alliaceae) from Tajikistan, Uzbekistan
    The alliances of Allium filidens Regel and A. brevidens Vved. were taxonomically revised. Three subspecies were recognized for A. filidens. The widely distributed typical subspecies is characterized by thick reticulate bulb tunics, relatively short leaf sheathes, and whitish tepals with greenish or bluish median veins. Subspecies ugamicum (Vved.) R.M.Fritsch & F.O.Khass. occurring in Chatkal, Pskem, and Ugam mountain ranges E and NE of Tashkent, has delicate, reticulate bulb tunics, relatively longer leaf sheathes, and faintly blue to violet flowers. Subspecies mogianense R.M.Fritsch & F.O.Khass. occupies a small area of distribution in western Hissar mountain range and differs from subsp. ugamicum by greenish tepals with broad green median veins. A key for determination of these subspecies is given. Allium brevidens subsp. pshikharvium R.M.Fritsch & F.O.Khass. was newly described from higher altitudes of Tajik Vanch, Darvaz, and Peter I. mountain ranges. It differs from the typical subspecies by larger scapes, denser inflorescences, green (not yellowish) tepals with dark-green median veins and violet (not purplish) filaments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Neue Taxa von Allium L. subg. Allium (Alliaceae) aus Tadschikistan und Usbekistan Die Verwandtschaftskreise von Allium filidens Regel and A. brevidens Vved. umfassen jeweils mehrere Unterarten. Die typische Unterart von A. filidens ist weit verbreitet und besitzt dicke, reticulate Zwiebelhüllen, relativ kurze Blattscheiden und weißliche Tepalen mit grünlichem oder bläulichem Mittelnerv. Pflanzen aus den Gebirgen im Norden und Nordosten von Taschkent haben sehr zarte reticulate Zwiebelhüllen, relativ längere Blattscheiden und blaßblaue bis violette Blüten. Sie werden als subsp. ugamicum (Vved.) R.M.Fritsch & F.O.Khass. neu kombiniert. Die neu beschriebene subsp. mogianense R.M.Fritsch & F.O.Khass. ist nur aus dem westlichen Hissar-Gebirge bekannt und unterscheidet sich von subsp. ugamicum durch grünliche Tepalen mit breitem grünem Mittelnerv. Ein Schlüssel der Unterarten wird präsentiert. Aus höheren Gebirgslagen in Tadschikistan wird A. brevidens subsp. pshikharvium R.M.Fritsch & F.O.Khass. neu beschrieben, das sich von der typischen Unterart durch längere Schäfte, dichtere Blütenstände, grüne (nicht gelbliche) Tepalen mit dunkelgrünem Mittelnerv sowie violette (nicht purpurne) Filamente unterscheidet. [source]


    Enigma variations: the stratigraphy, provenance, palaeoseismicity and depositional history of the Lower Old Red Sandstone Cosheston Group, south Pembrokeshire, Wales

    GEOLOGICAL JOURNAL, Issue 5 2006
    Richard G. Thomas
    Abstract The Lower Devonian (Lochkovian-Emsian) Cosheston Group of south Pembrokeshire is one of the most enigmatic units of the Old Red Sandstone of Wales. It consists of a predominantly green, exceptionally thick succession (up to 1.8,km) within the red c. 3,km-thick fill of the Anglo-Welsh Basin, but occupies a very small area (27,km2). Four formations,Llanstadwell (LLF), Mill Bay (MBF), Lawrenny Cliff (LCF) and New Shipping (NSF),group into lower (LLF,+,MBF) and upper (LCF,+,NSF) units on stratigraphical and sedimentological criteria. Two palynostratigraphic associations (Hobbs Point and Burton Cliff) are recognised in the LLF. Overall, the Cosheston succession comprises a fluvial, coarsening-upward megasequence, mostly arranged in fining-upward rhythms. It is interpreted as the fill of an east-west graben bounded by faults to the north and south of the Benton and Ritec faults, respectively. Both ,lower Cosheston' formations were deposited by east-flowing, axial river systems draining a southern Irish Sea landmass. Drainage reversal, early in the deposition of the LCF, resulted in ,upper Cosheston' lateral, SW-flowing rivers which carried predominantly second- and multi-cycle detritus. The ,lower Cosheston' is characterized by an abundance of soft-sediment deformation structures, probably seismically triggered by movements along the graben's northern bounding fault. A minimum average (, mesoseismic) earthquake recurrence interval of c. 4000,yr is estimated for the MBF. This and the correlative Senni Formation of south-central Wales form a regionally extensive green-bed development that represents a pluvial climatic interval. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    The source process of the 2001 July 26 Skyros Island (Greece) earthquake

    GEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2004
    Zafeiria Roumelioti
    SUMMARY The spatial and temporal distribution of slip during the 2001 July 26 Skyros (Greece) earthquake Moment magnitude (M 6.5) is investigated using broadband data recorded at regional distances. The applied method involves estimation of the source time functions of the examined event through an empirical Green's function approach and inversion of their shapes to estimate kinematic source parameters. Our test inversions to statistically identify the fault plane, together with the distribution of aftershocks clearly indicate sinistral strike-slip faulting. In view of the fact that the Skyros epicentre lies near the western termination of the dextral strike-slip North Anatolian Fault (NAF) into the Aegean Sea, this sinistral strike-slip motion, for the first time instrumentally identified, has great tectonic significance. The best values searched through the inversion are 0.7 s for the rise time, and 2.4 km s,1 for the rupture velocity. Most of the slip appears to be concentrated in a relatively small area around the hypocentre, while a smaller slip patch was found at relatively large depth (18,24 km). At least two of the large aftershocks following the main event also occurred at the deeper part of the fault. Smaller amounts of slip are distributed in a wider area with dimensions similar to those inferred from the aftershock distribution studies and the empirical relations applicable to Greece. [source]


    Neurochemistry of Trigeminal Activation in an Animal Model of Migraine

    HEADACHE, Issue 2006
    Michael L. Oshinsky PhD
    Research techniques such as electrophysiology, cFos protein expression, and other measurements of neuronal activation provide insights into the pathophysiology of pain processing in migraine, but they do not indicate the specific neurotransmitter systems involved. This paper summarizes data from microdialysis experiments in which changes in the neurochemistry of the trigeminal nucleus caudalis (TNC) were monitored during dural stimulation. Microdialysis allows the measurement of extracellular concentrations of neurotransmitters in a small area of the brain, in vivo, by means of a probe equipped with a semipermeable membrane. Microdialysis enables direct measurement of changes in extracellular concentrations of neurotransmitters in the intact animal over time in response to dural inflammation. Following the activation of the dural nociceptors, changes in the extracellular amino acid neurotransmitters in the deep lamina of the TNC were tracked. A 5-minute application of inflammatory soup when compared with saline to the dura of rats induced a transient decrease in extracellular glutamate in the TNC at approximately 30 minutes postapplication. This short-lived decrease was followed by a continuous increase in extracellular glutamate to a level of approximately 3 times the baseline value at 3 hours after application of the inflammatory soup. The time course of this increase in extracellular glutamate correlated with changes in sensory thresholds on the face of the rat from electrophysiological recordings of secondary sensory neurons in the TNC. No significant differences between the inflammatory soup and saline conditions were observed for extracellular concentrations of aspartate (an excitatory amino acid) or the inhibitory neurotransmitters gamma-aminobutyric acid or glutamine. Results of these experiments support an integral role for glutamate in central sensitization of neurons in the TNC, and suggest an important contribution of glutamate to allodynia and hyperalgia in this animal model of migraine. [source]


    Wavelet analysis of inter-annual variability in the runoff regimes of glacial and nival stream catchments, Bow Lake, Alberta

    HYDROLOGICAL PROCESSES, Issue 6 2003
    Melissa Lafrenière
    Abstract Continuous wavelet analyses of hourly time series of air temperature, stream discharge, and precipitation are used to compare the seasonal and inter-annual variability in hydrological regimes of the two principal streams feeding Bow Lake, Banff National Park, Alberta: the glacial stream draining the Wapta Icefields, and the snowmelt-fed Bow River. The goal is to understand how water sources and flow routing differ between the two catchments. Wavelet spectra and cross-wavelet spectra were determined for air temperature and discharge from the two streams for summers (June,September) 1997,2000, and for rainfall and discharge for the summers of 1999 and 2000. The diurnal signal of the glacial runoff was orders of magnitude higher in 1998 than in other years, indicating that significant ice exposure and the development of channelized glacial drainage occurred as a result of the 1997,98 El Niño conditions. Early retreat of the snowpack in 1997 and 1998 led to a significant summer-long input of melt runoff from a small area of ice cover in the Bow River catchment; but such inputs were not apparent in 1999 and 2000, when snow cover was more extensive. Rainfall had a stronger influence on runoff and followed quicker flow paths in the Bow River catchment than in the glacial catchment. Snowpack thickness and catchment size were the primary controls on the phase relationship between temperature and discharge at diurnal time scales. Wavelet analysis is a fast and effective means to characterize runoff, temperature, and precipitation regimes and their interrelationships and inter-annual variability. The technique is effective at identifying inter-annual and seasonal changes in the relative contributions of different water sources to runoff, and changes in the time required for routing of diurnal meltwater pulses through a catchment. However, it is less effective at identifying changes/differences in the type of the flow routing (e.g. overland flow versus through flow) between or within catchments. Copyright © 2003 John Wiley & Sons, Ltd. [source]


    Characteristics of preferential flow and groundwater discharge to Shingobee Lake, Minnesota, USA

    HYDROLOGICAL PROCESSES, Issue 10 2002
    Hans F. Kishel
    Abstract Small-scale heterogeneities and large changes in hydraulic gradient over short distances can create preferential groundwater flow paths that discharge to lakes. A 170 m2 grid within an area of springs and seeps along the shore of Shingobee Lake, Minnesota, was intensively instrumented to characterize groundwater-lake interaction within underlying organic-rich soil and sandy glacial sediments. Seepage meters in the lake and piezometer nests, installed at depths of 0·5 and 1·0 m below the ground surface and lakebed, were used to estimate groundwater flow. Statistical analysis of hydraulic conductivity estimated from slug tests indicated a range from 21 to 4·8 × 10,3 m day,1 and small spatial correlation. Although hydraulic gradients are overall upward and toward the lake, surface water that flows onto an area about 2 m onshore results in downward flow and localized recharge. Most flow occurred within 3 m of the shore through more permeable pathways. Seepage meter and Darcy law estimates of groundwater discharge agreed well within error limits. In the small area examined, discharge decreases irregularly with distance into the lake, indicating that sediment heterogeneity plays an important role in the distribution of groundwater discharge. Temperature gradients showed some relationship to discharge, but neither temperature profiles nor specific electrical conductance could provide a more convenient method to map groundwater,lake interaction. These results suggest that site-specific data may be needed to evaluate local water budget and to protect the water quality and quantity of discharge-dominated lakes. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    Resident and transient dynamics, site fidelity and survival in wintering Blackcaps Sylvia atricapilla: evidence from capture,recapture analyses

    IBIS, Issue 2 2007
    EDUARDO J. BELDA
    In their winter quarters, migrant birds may either remain within a small area (resident strategy) or move frequently over a large area looking for locally abundant food (transient strategy). It has been suggested that both strategies could simultaneously occur in the same population. We used time-since-marking capture,recapture models to infer the coexistence of these two behavioural strategies (transient and resident) among wintering Blackcaps Sylvia atricapilla using weekly recapture data over a 7-year period. A related question is whether Blackcaps, if surviving to the next winter, always return to the same wintering area, so we also used this approach to analyse winter site fidelity and to estimate annual survival probabilities. Model selection supported the existence of heterogeneity in survival estimates for both the within-season and the interannual survival probabilities, i.e. there was evidence for the existence of transients. It was estimated that 26% of the Blackcaps were resident during the winter. Mean apparent annual survival probability was 0.46 (se = ±0.11). However, there was some evidence suggesting that not all individuals showed winter site fidelity. The estimated proportion of individuals that, if alive, returned to the wintering area was 28%. This is the first study to show the existence of these two behavioural strategies (residence and transience) among wintering Blackcaps, and the first confirming this pattern using capture,recapture models. These models considering transient and resident dynamics may become an important tool with which to analyse wintering strategies. [source]


    Sensitivity analysis of snow patterns in Swiss ski resorts to shifts in temperature, precipitation and humidity under conditions of climate change

    INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2009
    Bastienne Uhlmann
    Abstract The value of snow as a resource has considerably increased in Swiss mountain regions, in particular in the context of winter tourism. In the perspective of a warming climate, it is thus important to quantify the potential changes in snow amount and duration that could have large repercussions on the economy of ski resorts. Because of the fine spatial variability of snow, the use of a Surface Energy Balance Model (SEBM) is adequate to simulate local snow cover evolution. A perturbation method has been developed to generate plausible future meteorological input data required for SEBM simulations in order to assess the changes in snow cover patterns. Current and future snow depths have also been simulated within the ski areas themselves. The results show a large decrease of the snow depths and duration, even at high elevation in a warmer climate and emphasize the sensitivity of snow to topographical characteristics of the resorts. The most vulnerable areas would be the Western regions of Switzerland or the Eastern Prealps whereas the Central Alps or Valais would be less affected. The study highlights the fact that not only the altitude of a domain but also its exposure, localization inland and slope gradients need to be taken into account when evaluating current and future snow depths. This method enables a precise assessment of the snow pattern over a small area. Copyright © 2008 Royal Meteorological Society [source]


    Location-related differences in structure and function of the stratum corneum with special emphasis on those of the facial skin

    INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2008
    H. Tagami
    Synopsis Between the two different kinds of the skin covering the body, the glabrous skin is found only on the palmo-plantar surface because of its rather simple function to protect the underlying living tissue with its remarkably thick stratum corneum (SC) from strong external force and friction. Thus, its barrier function is extremely poor. In contrast, the hair-bearing skin covers almost all over the body surface regardless of the presence of long hair or vellus hair. In regard to its SC, many dermatologists and skin scientists think that it is too thin to show any site-specific differences, because the SC is just present as an efficient barrier membrane to protect our body from desiccation as well as against the invasion by external injurious agents. However, there are remarkable regional differences not only in the living skin tissue but also even in such thin SC reflecting the function of each anatomical location. These differences in the SC have been mostly disclosed with the advent of non-invasive biophysical instruments, particularly the one that enables us to measure transepidermal water loss (TEWL), the parameter of the SC barrier function, and the one that evaluates the hydration state of the skin surface, the parameter of the water-holding capacity of the SC that brings about softness and smoothness to the skin surface. These in vivo instrumental measurements of the SC have disclosed the presence of remarkable differences in the functional properties of the SC particularly between the face and other portions of the body. The SC of the facial skin is thinner, being composed of smaller layers of corneocytes than that of the trunk and limbs. It shows unique functional characteristics to provide hydrated skin surface but relatively poor barrier function, which is similar to that observed in retinoid-treated skin or to that of fresh scar or keloidal scars. Moreover, there even exist unexpected, site-dependent differences in the SC of the facial skin such as the forehead, eyelid, cheek, nose and perioral regions, although each location occupies only a small area. Between these locations, the cheek shows the lowest TEWL in contrast to the perioral region that reveals the highest one. Moreover, these features are not static but change with age particularly between children and adults and maybe also between genders. Among various facial locations, the eyelid skin is distinct from others because its SC is associated with poor skin surface lipids and a thin SC cell layer composed of large corneocytes that brings about high surface hydration state but poor barrier function, whereas the vermillion borders of the lips that are covered by an exposed part of the oral mucosa exhibit remarkably poor barrier function and low hydration state. Future studies aiming at the establishment of the functional mapping in each facial region and in other body regions will shed light on more delicate site-dependent differences, which will provide us important information in planning the strategy to start so called tailor-made skin care for each location of the body. Résumé Entre les deux types différents de peau couvrant le crops, on trouve la peau glabre uniquement sur la surface palmo-plantaire du fait de sa fonction plutôt simple de protection du tissu vivant sous-jacent par un stratum corneum (SC) trés épais vis-à-vis des forces extérieures et de la friction. De ce fait, sa fonction barrière est extrêmement pauvre. Au contraire, la peau velue courve la presque totalité de la surface du crops, que ce soit par la présence de longs cheveux ou de duvet. En ce qui concerne son SC, la plupart des dermatologues et des scientifiques de la peau pensent qu'il est trop mince pour montrer une différence spécifique au site, attendu que le SC est simplement présent en tant que membrane barriére efficace pour protéger notre corps de la dessiccation ainsi que pour lutter contre l'invasion d'agents nuisibles externes. Cependant, il existe des différences importantes entre les sites, non seulement dans la peau vivante, mais également dans ce SC aussi mince, qui révèlent la fonctin de chaque site anatomique. Ces différences dans le SC ont surtout été révélées avec l'apparition d'instruments biophysiques non invasifs, en particulier celui qui nous permet de mesurer la perte transépidermale en eau (TEWL), le paramétre de la fonction barrière du SC et celui qui évalue l'état d'hydratation de la surface de peau, le paramètre de la capacité en rétention de l'eau du SC qui est liéà la souplesse et à la douceur à la surface de peau. Ces mesures instrumentales in vivo du SC ont révélé la présence de différences remarquables entre les propriétés fonctionnelles du SC particulièrement entre le visage et d'autres parties du corps. Le SC de la peau de la face est plus mince, car li est composé de couches plus petites de corneocytes que celui du tronc et des membres. Il montre des caractéristiques fonctionnelles uniques pour permettre l'hydratation de la surface de peau, mais une fonction barrière relativement faible, semblable à celle observée dans la peau traitée avec un rétinoïde ou à celle d'une cicatrice récente ou de cicatrices kéloidales. De plus, il existe des différences sites-dépendantes inattendues dans le SC de la peau de la face comme le front, la paupière, la joue, le nez et les régions périorales, et ce, bien que chaque emplacement occupe seulement un petit secteur. Entre ces divers emplacements, la joue montre le TEWL le plus bas par comparaison avec la région périorale qui montre le plus élevé. De plus, ces caractéristiques ne sont pas fixes, mais changent avec l'âge en particulier entre enfants et adultes et peut-être aussi entre sexes. Entre les diverses régions de la face, la peau de la paupière se distingue parce que son SC est associéà une peau pauvre en lipides de surface constituée par une mince couche de cellule composée de grand cornéocytes qui provoquent un haut état d'hydratation superficiel, mais une faible fonction barrière. A l'inverse les bordures vermillion des lévres recouvertes par une partie exposée de muqueuse orale, possèdent une fonction barrière très faible et un état d'hydratation bas. Les études futures visant àétablir la configuration fonctionnelle de chaque région de la face et d'autres régions du corps mettrons en lumière des différences sites-dépendantes plus subtiles, qui nous fourniront des informations importantes pour planifier la stratégie pour commencer le soin de la peau sur mesure si attendu pour chaque partie du corps. [source]


    The Spatial Segregation of Zooplankton Communities with Reference to Land Use and Macrophytes in Shallow Lake Wielkowiejskie (Poland)

    INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2009
    Natalia Kuczy, ska-Kippen
    Abstract The spatial distribution of zooplankton in relation to two types of land-use (forested and pastoral-arable) of a lake's surroundings and to various habitats (helophytes, elodeids, nymphaeids and open water) was examined along 16 parallel transects on a macrophyte-dominated lake (area , 13.3 ha; mean depth , 1.4 m). The type of habitat was the main determinant of zooplankton community structure. Dissected-leaved elodeids harboured the richest and most abundant community with typically littoral (e.g., Colurella uncinata) and pelagic species (e.g., Keratella cochlearis). Two species (Polyarthra major and P. vulgaris) selectively chose the open water and one (Lecane quadridentata) the Typha stand. No spatial differentiation in zooplankton abundance was recorded between the two types of the catchment area. One possible explanation may be the shallowness and small area of this lake which may support full mixing and no difference in physical-chemical gradients. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Small and large anemonefishes can coexist using the same patchy resources on a coral reef, before habitat destruction

    JOURNAL OF ANIMAL ECOLOGY, Issue 5 2002
    Akihisa Hattori
    Summary 1According to meta-population models, a superior competitor and a superior disperser can coexist in a patchy environment. The two anemonefishes, a large aggressive Amphiprion clarkii Bennett and a small less-aggressive A. perideraion Bleeker, use the same host anemone Heteractis crispa Ehrenberg on a coral reef, Okinawa, Japan, where most of the hosts disappeared after the coral bleaching in 1998. Their microhabitat (host) use and coexistence, and the quality and quantity of microhabitats were investigated in 1988, 1989, 1999 and 2000 on the coral reef. Their interspecific interaction was also examined. 2Before the habitat destruction, the two species coexisted. Although A. clarkii was behaviourally dominant over A. perideraion in a cohabiting group, A. perideraion was a superior competitor in terms of site displacement, because A. perideraion could displace a microhabitat. Adult A. clarkii emigrated from a cohabiting group probably due to the high cost of interactions with adult A. perideraion . Although it is easier to defend a small area for a larger species, sharing a host with adult A. perideraion may not pay for A. clarkii because A. clarkii needs a larger area. 3A. clarkii was not only a superior disperser, which was able to find a vacated host, but also a pioneer species that was able to use newly settled small hosts. Larval A. clarkii settled on such a small host because they were able to move to larger hosts for future reproduction, while A. perideraion did not settle on a small host because of low mobility after settlement. Microhabitat (host) with various sizes might have promoted their coexistence. 4After the habitat destruction, the superior competitor A. perideraion went extinct locally due probably to lack of small host utilization ability. The present study implies that the difference in body size between the two competitors plays an important role in their coexistence, because species with different body sizes can have different mobility and require different amounts of resources. [source]


    The ecological impacts of a migratory bat aggregation on its seasonal roost in Kasanka National Park, Zambia

    AFRICAN JOURNAL OF ECOLOGY, Issue 1 2010
    James W. Byng
    Abstract The ecological impacts of migratory species on their seasonal environments are poorly known. The effects of several million straw-coloured fruit bats (Eidolon helvum), which migrate seasonally to Kasanka National Park, Zambia each year, on the small area of mushitu,swamp' forest in which they roost, were investigated. The structure of the mushitu forest was profoundly altered by the presence of E. helvum, with increased roost tree mortality, lowering and opening of the forest canopy and a decrease in tree basal area. Eidolon helvum are also thought to increase the severity of fires within their roost site because the structural changes result in a drier microclimate. The effects of increased nitrogen and phosphorous input were less apparent. These findings suggest that the ecological impact of this migratory bat species on its seasonal environment could ultimately threaten the long-term viability of its seasonal roost. Résumé Les impacts écologiques des espèces migratrices sur leurs environnements saisonniers sont peu connus. Les effets de plusieurs millions de roussettes paillées africaines Eidolon helvum qui, chaque année, migrent de façon saisonnière vers le Parc National de Kasanka, en Zambie, furent étudiés dans la petite zone de forêt marécageuse àmushitu où elles se perchent. La structure de la forêt àmushituétait profondément modifiée par la présence d'E. helvum, qui augmentait la mortalité des arbres servant de perchoirs, qui faisait baisser la hauteur et la densité de la canopée et entraînait une diminution de la surface basale des arbres. On pense aussi que la présence d'E. helvum augmente la gravité des feux dans les sites de repos parce que les changements structurels aboutissent à un microclimat plus sec. Les effets de l'apport accru en azote et en phosphore étaient moins apparents. Ces découvertes suggèrent que l'impact écologique de cette espèce de chauve-souris migratrice sur son environnement saisonnier pourrait, à long terme, menacer la viabilité de ses lieux de repos saisonniers. [source]


    Timing of early amniocentesis as a function of membrane fusion

    JOURNAL OF CLINICAL ULTRASOUND, Issue 1 2004
    Michael G. Pinette MD
    Abstract Purpose The purpose of this prospective study was to evaluate sonographically the timing of membrane fusion and to determine its possible effect on the timing of amniocentesis. Methods Between May 18, 1998, and January 31, 2002, the status of amnion fusion in pregnant patients at 9,15 weeks' menstrual age was identified in women who were to undergo obstetric sonography. Amniocentesis was performed if even a small area of fused membranes that could be traversed was identified; if the membranes were completely unfused, amniocentesis was delayed. The effect of membrane fusion in terms of the need to reschedule amniocentesis was evaluated. Results We examined a total of 594 patients. Membrane fusion occurred progressively with increasing menstrual age. One hundred six early amniocenteses were scheduled, and 70 were performed; the others were delayed because the membranes were unfused. Our requirement that an area of membrane fusion be found before we would perform amniocentesis resulted in rescheduling the procedure 24,38% of the time. Conclusions Membrane fusion, as seen sonographically, is a function of menstrual age. Even by 15 weeks, a portion of the amnion may be unfused with the chorion. Amniocenteses scheduled for early in the pregnancy may need to be delayed until later, when the membranes are at least partially fused, allowing safe passage of a needle. Delaying the procedure may incur higher expense but may be important in terms of lessening the risk involved. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 32:8,11, 2004 [source]


    Ultrastructural study of skin and eye of UV-B irradiated ayu Plecoglossus altivelis

    JOURNAL OF FISH BIOLOGY, Issue 6 2005
    J. G. Sharma
    A scanning electron microscopic study of the skin and eye of UV-B radiated ayu Plecoglossus altivelis(age 30 days, mean ± s.e. total length: 16·25 ± 0·11 mm) under laboratory condition showed marked changes when compared with the control fish without UV-B radiation. The exposure of the fish to the radiation resulted in the destruction of microridges in the epidermis and exposed neuromast cells of the skin. Domed protrusions were also more common in the skin of UV-B radiated fish than in the control fish. The appearance of mucus in both groups was different. In the control skin the mucus was spread over a wide area whereas in the treated fish the mucus was concentrated in a small area. The anastomozing structures of the microridges of the eyes were lost in UV-B radiated fish and the microridges themselves were fewer in number, fragmented, and aggregated. Mucus cells, prominently visible in the control fish, were distorted in the treated fish. Cell contours were irregular in UV-B radiated fish and cell to cell contacts had been lost in this group. [source]


    Numerical analysis of thermal and electrochemical phenomena for anode supported microtubular SOFC

    AICHE JOURNAL, Issue 3 2009
    Daan Cui
    Abstract A 2D model considering momentum, heat/species transport and electrochemical phenomena, has been proposed for tubular solid oxide fuel cell. The model was validated using experimental polarization curves and the good agreement with the experimental data was attained. The temperature distributions show that temperature varies severely at the tube inlet than at the tube outlet. The heat generation and transfer mechanisms in electrodes, electrolyte and electrochemical reaction interface were investigated. The results show that the overall electrochemical reaction heat is produced at cathode/electrolyte interface, and a small portion of the heat is consumed at anode/electrolyte interface. The heat produced at cathode/electrolyte interface is about five times as much as that consumed at anode/electrolyte interface. Overwhelming part of the heat transfer between cell and outside occurs at cathode external surface. Most current flow goes into anode from a very small area where the current collectors locates. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source]


    Depigmentation of the normally pigmented patches in universal vitiligo patients by cryotherapy

    JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2000
    Mohammed Radmanesh
    Abstract Background Complete depigmentation may occur, albeit rarely, in patients with universal vitiligo. They usually have one or more pigmented patches that remain normal, most frequently over the malar area of the face and dorsal aspects of forearms. Total repigmentation may not occur in these patients, even after receiving 150 session of PUVA therapy alone or in conjunction with other medical or surgical procedures, and there is possibility of recurrence after cessation of therapy. These patients are usually more interested in depigmentation rather than trying for repigmentation. Objective Because of the relatively high sensitivity of melanocytes to cryotherapy and the possibility of isomorphic phenomenon in vitiligo patients, removal of the remaining normally pigmented patches was attempted in patients with universal vitiligo using cryotherapy. Method Five volunteer patients with universal vitiligo were chosen, all of whom wished to have their pigmented patches removed. In all five patients a small area was tested first in order to assure the patients of what the procedure involved and to show its likely result. All pigmented areas were then treated to 1,3 sessions of cryotherapy using a closed contact CO2 cryogun, with 4,6-week intervals. Results Complete and permanent depigmentation was achieved in all five patients with excellent cosmetic results and no complications or scarring. Conclusion Cryotherapy is a cost effective, non-complicating, easily available procedure which can be used for depigmentation of normally pigmented patches in patients with universal vitiligo. [source]


    Rarity and decline in palaeoendemic Martino's vole Dinaromys bogdanovi

    MAMMAL REVIEW, Issue 4 2008
    BORIS KRY, TUFEK
    ABSTRACT 1Martino's vole Dinaromys bogdanovi is the only living member of the Tertiary genus Dinaromys, and probably also the only surviving member of the Pliomys lineage. The range of the genus Dinaromys has historically been small and its rate of evolution has been low. 2Martino's vole shows all three attributes of rarity in accordance with Rabinowitz's ,seven forms of rarity' model: (i) its range is estimated at 43 545 km2 but the area of occupancy is <5200 km2; (ii) its habitat requirements are narrow and the species is strictly tied to exposed, karstified bedrock; and (iii) current populations are invariably small and frequently isolated. 3The Pleistocene range of Martino's vole exceeded the recent one, at least in the north-western part of the Balkans, and its shrinkage continued into the Holocene. 4Martino's vole may be in competition with the European snow vole Chionomys nivalis, which has a very similar morphology and presumably identical habitat requirements, but is shifted towards an r-selected life-history strategy. Long-term sympatry of these voles has probably resulted in competitive exclusion of the relatively K-selected Martino's vole by the relatively r-selected European snow vole. 5Martino's vole consists of two deeply divergent (about one million years ago) phylogeographical lineages, which may represent distinct cryptic species. Rarity is particularly pronounced in the north-western lineage to the west of the Neretva River, where rocky habitats are largely occupied by the European snow vole. 6In the IUCN Red List of Threatened Animals, Martino's vole is classified as ,near threatened'. However, the north-western lineage, which is phylogeographically most divergent and has the greatest genetic diversity, is classed as a ,vulnerable' evolutionary significant unit on the basis of its small area of occupancy (<2000 km2). Long-term population monitoring is an essential step in evaluating the conservation needs of Martino's vole. [source]


    A low voltage folded cascode LNA for ultra-wideband applications

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2010
    Sunil L. Khemchandani
    Abstract A low noise amplifier scheme to achieve low-voltage and wide-bandwidth operation is presented. This circuit is based on folded cascode topology combined with wideband impedance matching and shunt peaking load. One of the drawbacks of the proposed scheme is that it uses more area than the conventional cascode due to the two additional inductors and capacitors to implement the capacitively coupled LC tanks. To reduce the area of the circuit, we have used stacked inductors, a brief study of these kinds of inductors is presented. Two low noise amplifiers have been fabricated using a mature 0.35 ,m BiCMOS technology, one using the cascode conventional approach and the other using the proposed topology. Measurement results show that for the same transistors operating conditions, the low-voltage amplifier performance is similar than the conventional cascode. By virtue of the small area of stacked inductors, the size of both low noise amplifiers is comparable. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2495,2500, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25530 [source]


    Simple small-size coupled-fed uniplanar PIFA for multiband clamshell mobile phone application

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2009
    Ting-Wei Kang
    Abstract In this study, a simple uniplanar printed PIFA occupying a small area of 10 × 40 mm2 for achieving multiband operation in the clamshell mobile phone is presented. The proposed PIFA is formed by a simple shorted radiating strip coupled-fed by a simple feeding strip and is mounted at the hinge of the clamshell mobile phone; further, the upper ground plane is connected to the main ground plane using an extended connecting strip. With the coupling feed and the connection arrangement between the main and upper ground planes, the proposed PIFA itself is not only an efficient radiator, it can also excite the two ground planes of the clamshell mobile phone as an efficient radiator (dipole-like resonant modes are excited). Thus, with a small occupying area and a simple structure for the proposed PIFA, two wide operating bands at lower and higher frequencies can be provided to cover GSM850/900/1800/1900/UMTS bands for WWAN operation. The antenna also meets the 1-g SAR specification of 1.6 W/kg required for practical applications. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2805,2810, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24756 [source]


    Uniplanar coupled-fed printed PIFA for WWAN/WLAN operation in the mobile phone

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2009
    Cheng-Tse Lee
    Abstract A coupled-fed printed planar inverted-F antenna (PIFA) with a compact uniplanar structure for easy implementation in the mobile phone for WWAN/WLAN operation is presented. The printed PIFA occupies a small area of 10 × 60 mm2 and provides two wide operating bands (the lower and upper bands) at about 900 and 2000 MHz for covering GSM850/900/DCS/PCS/UMTS/WLAN six-band operation. The printed PIFA is formed by two coupled-fed PIFAs of different sizes, a longer radiating/coupling portion and a shorter radiating/coupling portion. Owing to the use of the coupling feed, both of the two portions can generate dual-resonance excitation, with the longer portion providing a wide lower band for GSM850/900 operation and the shorter portion providing a wide upper band for DCS/PCS/UMTS/WLAN operation. In addition, the lower and upper bands of the printed PIFA can generally be controlled separately by the longer and shorter portions, making it easy for fine tuning of the desired operating bands in practical applications. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1250,1257, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24298 [source]


    A wideband planar monopole microstrip antenna with coupled parasitic lines

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2006
    Lu Lu
    Abstract A wideband microstrip-fed monopole antenna with two shorted inverted-L coupled lines is presented. The proposed antenna has a large impedance bandwidth covering the range from 3.22 to 11.68 GHz. The radiating elements only occupy a small area of 9.3 × 8.2 mm2. The gain and bandwidth of the antenna are predicted using a commercial finite-element method software package. For frequencies across the operating bands, the proposed antenna displays monopolelike radiation patterns and good antenna gain, given its small physical size. The predicted results show good agreement with measured data. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1507,1509, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21718 [source]