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Vicinity
Kinds of Vicinity Selected AbstractsThe Bold and the Variable: Fish with High Heterozygosity Act Recklessly in the Vicinity of PredatorsETHOLOGY, Issue 1 2008Sampsa Vilhunen Variation in the innate behavioral response to predation threat is often assumed to reflect genetic differences among the prey individuals. To date, no published results, however, exist that would offer explanation for the origin of this behavioral variation within populations. Using microsatellites as markers, we estimated the genetic variability of juvenile brown trout (Salmo trutta) individuals whose behavior had been individually recorded in a trade-off situation where both predator chemical cues and food were present. Mean overall heterozygosity and the internal relatedness of fish associated significantly with their activity and foraging, so that the genetically more variable individuals showed more risk-prone behavior under predation risk. No association between genetic variability and behavior was found in trials where predator odors were not present. These results were consistent over the three study populations of brown trout with different backgrounds, suggesting that the phenomenon is of general nature in this species. Of the possible mechanisms suggested to enable the existence of the positive association between neutral microsatellite variation and fitness-related trait, the local effect hypothesis gained more support from our data than the general effect hypothesis. [source] Drawdown and Stream Depletion Produced by Pumping in the Vicinity of a Partially Penetrating StreamGROUND WATER, Issue 5 2001James J. Butler Jr. Commonly used analytical approaches for estimation of pumping-induced drawdown and stream depletion are based on a series of idealistic assumptions about the stream-aquifer system. A new solution has been developed for estimation of drawdown and stream depletion under conditions that are more representative of those in natural systems (finite width stream of shallow penetration adjoining an aquifer of limited lateral extent). This solution shows that the conventional assumption of a fully penetrating stream will lead to a significant overestimation of stream depletion (> 100%) in many practical applications. The degree of overestimation will depend on the value of the stream leakance parameter and the distance from the pumping well to the stream. Although leakance will increase with stream width, a very wide stream will not necessarily be well represented by a model of a fully penetrating stream. The impact of lateral boundaries depends upon the distance from the pumping well to the stream and the stream leakance parameter. In most cases, aquifer width must be on the order of hundreds of stream widths before the assumption of a laterally infinite aquifer is appropriate for stream-depletion calculations. An important assumption underlying this solution is that stream-channel penetration is negligible relative to aquifer thickness. However, an approximate extension to the case of nonnegligible penetration provides reasonable results for the range of relative penetrations found in most natural systems (up to 85%). Since this solution allows consideration of a much wider range of conditions than existing analytical approaches, it could prove to be a valuable new tool for water management design and water rights adjudication purposes. [source] Reply to "Comment on the Magnetocaloric Effect of LaFe11.6Si1.4, La0.8Nd0.2Fe11.5Si1.5, and Ni43Mn46Sn11 Compounds in the Vicinity of the First-Order Phase Transition"ADVANCED MATERIALS, Issue 37 2009Jun-Ding Zou The magnetocaloric effect (MCE) of Ni43Mn46Sn11 in the vicinity of a first-order martensitic phase transition is discussed by using magnetic measurements, heat capacity measurements and differential scanning calorimetry (DSC) measurements. The results confirm that the MCE of Ni43Mn46Sn11 obtained by magnetic measurements (via the Maxwell relation) may be seriously overestimated and Ni-Mn-Sn alloys should be treated carefully. [source] Erratum: The Magnetocaloric Effect of LaFe11.6Si1.4, La0.8Nd0.2Fe11.5Si1.5, and Ni43Mn46Sn11 Compounds in the Vicinity of the First-Order Phase TransitionADVANCED MATERIALS, Issue 37 2009Jun-Ding Zou No abstract is available for this article. [source] The Magnetocaloric Effect of LaFe11.6Si1.4, La0.8Nd0.2Fe11.5Si1.5, and Ni43Mn46Sn11 Compounds in the Vicinity of the First-Order Phase TransitionADVANCED MATERIALS, Issue 6 2009Jun-Ding Zou The magnetocaloric effect is discussed in terms of the thermodyna mic Maxwell relation and its necessary conditions. The origin of the sharp "spikes" that appear in entropy-change curves is discussed. The Maxwell relation and heat-capacity measurements are then used to determine the entropy change and are applied to the discussion of LaFe11.6Si1.4, La0.8Nd0.2Fe11.5Si1.5, and Ni43Mn46Sn11 compounds. [source] Deviation of Fiber Tracts in the Vicinity of Brain Lesions: Evaluation by Diffusion Tensor ImagingISRAEL JOURNAL OF CHEMISTRY, Issue 1-2 2003Yaniv Assaf Diffusion Tensor Imaging (DTI) is used to characterize the diffusion properties of deviated white matter caused by brain tumors. DTI was recently shown to be very helpful in delineating white matter both within brain lesions and surrounding them. Displacement of white matter fibers may be one of the consequences of tumor growth adjacent to white matter. The combination of white matter mapping with DTI and gray matter mapping using functional MRI, in some cases, facilitated assessment of the relation between the shifted cortical areas and the corresponding white matter tracts. We found that the fractional anisotropy extracted from DTI is increased by 38% in areas of non-edematous shifted white matter fibers. By contrast, trace apparent diffusion coefficient (ADC) values in those areas were found to be similar to contralateral side and normal control values. Analysis of the three diffusion tensor eigenvalues revealed that the increase in the fractional anisotropy is a result of two processes. The first is the increase in the diffusion parallel to the fibers,,1 (by 18%), and the second is the decrease in the diffusion perpendicular to fibers,,3 (by 34%) as compared with the contralateral side. These opposing changes cause an increase in the diffusion anisotropy but no change in the trace ADC. It is suggested that the pressure caused by the tumor may lead to an increase in white matter fiber tension, thus causing an increase in ,1. On the other hand, the same pressure causes increased fiber density per unit area, leading to a higher degree of restricted diffusion in the extracellular space and, hence, a reduction in ,3. [source] Conductivity and Permittivity of Nickel-Nanoparticle-Containing Ceramic Materials in the Vicinity of Percolation ThresholdJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2006Umar Abdurakhmanov Conductivity and static permittivity of ceramic materials containing nanoparticles of Ni were measured in the vicinity of percolation threshold. It is found that, below this threshold, the experimentally obtained dependences of conductivity and static permittivity on the fractional Ni content in these materials are different from those calculated in the frame of the percolation theory. The origin of this discrepancy is discussed in terms of the network hierarchy model proposed recently by Balberg et al. for composite materials. [source] Spatial pattern and neighbour effects on Helianthemum squamatum seedlings in a Mediterranean gypsum communityJOURNAL OF VEGETATION SCIENCE, Issue 4 2005Adrián Escudero Abstract Question: Do, in a semi-arid gypsum environment, neighbours condition the spatial patterns of emergence, survival and height of Helianthemum squamatum seedlings? Location: Vicinity of Chinchón, province of Madrid, Spain (40°11,N, 3° 35,W, 550 m a.s.l.) Methods: We evaluated the effects of neighbours on the survival and growth of naturally emerging Helianthemum seedlings in a semi-arid area during a two-year period. We followed a two-fold approach based on the use of neighbour models for seedling survival and growth and spatial point pattern analyses for seedling emergence, taking into account the germination date. Results: Seedlings appeared clumped in the vicinity of mature Helianthemum individuals. The neighbour models fitted showed that interactions with neighbours were extremely important for the survival and growth of Helianthemum seedlings. These models also suggest that the effects of neighbours on these variables vary with changes in spatial scale and in the abiotic conditions. Some species exerted negative or positive effects on Helianthemum seedlings only at certain spatial scales, and others exerted negative or positive effects at earlier stages of seedling development, but none later and vice versa. Conclusions: We suggest that the observed patterns are mainly influenced by small-scale modifications in soil conditions and microclimate created by neighbours, which change in time and space. [source] Clinical Implications of a Close Vicinity of Nervus Dorsalis Penis/Clitoridis and Os PubisTHE JOURNAL OF SEXUAL MEDICINE, Issue 7 2008ABSTRACT Introduction., Close relation of nervus dorsalis penis/clitoris and os pubis has a major impact in surgical disciplines. Aim., To summarize a current knowledge about this region, represented by the course of sulcus nervi dorsalis penis/clitoridis. Methods., Literature search of years 1970,2007. Main Outcome Measures., In male, it accommodates nervus dorsalis penis whereas in female nervus et arteria dorsalis clitoridis. Lateral border of sulcus nervi dorsalis penis corresponds to vertical ridge and lateral border of sulcus nervi dorsalis clitoridis to ventral arc,two parameters, which are parts of the Phenice's method for sexing of isolated os pubis. Results., Exact preparation of nervus dorsalis penis is crucial in correct performance of conversion of genitalia in patients with transsexualism, in reconstruction of posterior urethra, in hypospadia, during performance of penile blockade during circumcision and in revascularization surgery of erectile dysfunction. Possible role of the sulcus nervi dorsalis penis in the Alcock's syndrome is discussed. Similarly, it is advisable to take care of nervus dorsalis clitoridis during reduction clitoridoplasty in patients with adrenogenital syndrome and during the insertion of transobturator vaginal tape. Injury of nervus dorsalis penis/clitoridis leads to hypestesia or anestesia of glans penis/clitoridis. The injury to arteria dorsalis clitoridis leads to bleeding and/or hematoma. Conclusions., Clinical anatomy of sulci is important in several situations in urologic surgery. It is possible to use sulcus nervi dorsalis penis/clitoridis for sexing of isolated pubis for antropological or forensic purposes.,edý J, Na,ka O, ,pa,ková J, and Jarolím L. Clinical implications of a close vicinity of nervus dorsalis penis/clitoridis and os pubis. J Sex Med 2008;5:1572,1581. [source] Seismogenic Structure around the Epicenter of the May 12, 2008 Wenchuan Earthquake from Micro-seismic TomographyACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2009Meijian AN Abstract: A three-dimensional local-scale P -velocity model down to 25 km depth around the main shock epicenter region was constructed using 83821 event-to-receiver seismic rays from 5856 aftershocks recorded by a newly deployed temporary seismic network. Checkerboard tests show that our tomographic model has lateral and vertical resolution of ,2 km. The high-resolution P -velocity model revealed interesting structures in the seismogenic layer: (1) The Guanxian-Anxian fault, Yingxiu-Beichuan fault and Wenchuan-Maoxian fault of the Longmen Shan fault zone are well delineated by sharp upper crustal velocity changes; (2) The Pengguan massif has generally higher velocity than its surrounding areas, and may extend down to at least ,10 km from the surface; (3) A sharp lateral velocity variation beneath the Wenchuan-Maoxian fault may indicate that the Pengguan massif's western boundary and/or the Wenchuan-Maoxian fault is vertical, and the hypocenter of the Wenchuan earthquake possibly located at the conjunction point of the NW dipping Yingxiu-Beichuan and Guanxian-Anxian faults, and vertical Wenchuan-Maoxian fault; (4) Vicinity along the Yingxiu-Beichuan fault is characterized by very low velocity and low seismicity at shallow depths, possibly due to high content of porosity and fractures; (5) Two blocks of low-velocity anomaly are respe tively imaged in the hanging wall and foot wall of the Guanxian-Anxian fault with a ,7 km offset with ,5 km vertical component. [source] Effect of a Magnetic Field on a Micropolar Fluid Flow in the Vicinity of an Axisymmetric Stagnation Point on a Circular CylinderCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 8 2009G. M. Abdel-Rahman Abstract The effect of a magnetic field on a micropolar fluid flow in the vicinity of an axisymmetric stagnation point on a circular cylinder is studied numerically. The governing conservation equations of continuity, momentum and angular momentum are partial differential equations which are transformed into a system of ordinary differential equations by using the usual similarity transformations. The resulting system of coupled non-linear ordinary differential equations is solved numerically by using the shooting method. The numerical results indicate the velocity, angular velocity and pressure distributions for different parameters of the problem including Reynolds number, magnetic parameter and dimensionless material properties, etc. In addition, the effect of the pertinent parameters on the local skin friction coefficient and the couple stress are discussed numerically and illustrated graphically. [source] ChemInform Abstract: Coordination of Cu+ and Cu2+ Ions in ZSM-5 in the Vicinity of Two Framework Al Atoms.CHEMINFORM, Issue 31 2001Dana Nachtigallova Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Use of deltamethrin ,pour-on' insecticide for the control of cattle trypanosomosis in the presence of high tsetse invasionMEDICAL AND VETERINARY ENTOMOLOGY, Issue 1 2001G. J. Rowlands Summary A deltamethrin ,pour-on' insecticide was applied monthly to over 2000 cattle exposed to a high challenge of drug-resistant trypanosomes and high tsetse re-invasion pressure in the Ghibe valley, south-west Ethiopia. Blood samples were taken monthly from an average of 760 cattle for determination of PCV and presence of trypanosomes. The area of the valley is approximately 350 km2 and the cattle grazed in roughly four locations covering about a quarter to half of the area. Two years before the trial commenced, Glossina morsitans submorsitans Newstead (Diptera: Glossinidae) began to invade the valley. Despite the use of the pour-on the mean apparent density of G. m. submorsitans continued to rise, and, during the 4 years of tsetse control, was more than three-fold higher than that recorded during the previous 18 months. Over the same period there was little change in the apparent density of Glossina pallidipes Austen (Diptera: Glossinidae). By contrast, the mean monthly prevalence of trypanosome infections in cattle over 36 months of age decreased from 38.3 to 29.0%, the incidence of new infections decreased from 26.6 to 16.0% (a reduction of 40%), and packed cell volume in cattle increased from 21.7 to 24.1%. Evidence of a change in apparent parasite transmission rate was demonstrated by regression of infection incidence in cattle on the logarithm of apparent density of G. m. submorsitans. Before the trial started the regression coefficient was 45.8 ± 6.3 and this reduced to 9.2 ± 2.5% incidence per loge (flies/trap/day) during the period of tsetse control. It was concluded that this indicated reductions in tsetse numbers in the immediate vicinities of cattle in a way that was not reflected in overall tsetse catches. Nevertheless, the comparatively high levels of trypanosome prevalence that persisted in the cattle demonstrates that, where invasion prevalence is high, treatment of small pockets of cattle will not eradicate tsetse. To achieve more significant reduction in trypanosome prevalence in cattle, integrated methods of control utilizing target barriers in the major routes of invasion will be needed. [source] Fire-mediated interactions between shrubs in a South American temperate savannahOIKOS, Issue 9 2009Fernando Biganzoli We examined spatial patterns of fire-caused mortality and after-fire establishment of two dominant shrub species, Baccharis dracunculifolia and Eupatorium buniifolium in a humid temperate South American savannah. Our objective was to determine whether fires mediate in interactions between these two species. After a natural fire burned a large tract of savannah, we established two plots (respectively 550 and 500 m2) within which we mapped all surviving and dead shrubs as well as all individuals of shrub species that recruited in the following year. We used techniques of point-pattern analysis to test specific null hypotheses about spatial associations in the distribution, mortality, and establishment of shrubs. Results support the notions that fire mediates interactions between these two species. Fire-caused death of E. buniifolium tended to occur selectively in the vicinities of Baccharis individuals, and recruitment of B. dracunculifolia tended to be concentrated in the places of dead shrubs. These responses, however, were contingent on local abundances of shrubs which depend in part from the recent fire history. Anthropogenic perturbation of the natural fire regime would have therefore distorted the role of fire mediated interactions as drivers of the dynamics of the vegetation of this temperate savannah. [source] High prevalence of parkinsonian disorders associated to manganese exposure in the vicinities of ferroalloy industriesAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 11 2007Roberto G. Lucchini MD Abstract Objective To assess the prevalence of Parkinsonian disturbances in relationship to environmental exposure to manganese due to ferroalloy industries in the province of Brescia, Northern Italy. Methods Manganese concentrations were measured in settled dust collected in each of the 206 municipalities. Parkinsonian patients were identified using two sources: (1) clinical registers from local hospitals, specialized neurologists, and exemption from prescription payment; (2) L-Dopa prescriptions. Standardized prevalence rates and raw and full Bayesian-smoothed standardized morbidity ratios (SMRs) were calculated for the entire province and for each municipality. Results Manganese concentrations in settled dust were significantly higher in the surroundings and downwind from the industrial plants. A total number of 2,677 Parkinsonian cases were identified among 903,997 residents (crude prevalence, 296/100,000; 95% CI: 284.80,307.20; standardized prevalence, 407/100,000; 95% CI: 393.87,420.12). Significantly higher SMRs (Kruskal,Wallis ,2 1 df,=,17.55, P,<,0.001) were observed in 37 municipalities in the vicinities of ferromanganese plants (324 cases among 77,708 residents; standardized prevalence 492/100,000; 95% CI: 442.80,541.20), compared to the other 169 municipalities of the province (2,353 cases among 826,289 residents, standardized prevalence 321/100,000; 95% CI 308.80,333.20). Row and Bayesian SMRs were associated with the concentrations of manganese in settled dust. Conclusion Study results suggest that environmental exposure to manganese is associated with an increased prevalence of Parkinsonian disturbances. Since the highest prevalence rates were observed in a closed community of the pre-Alps where the industries are located, further research should address a possible interactive role of genetic factors. Am. J. Ind. Med. 50:788,800, 2007. © 2007 Wiley-Liss, Inc. [source] Visual Support for Interactive Post-Interventional Assessment of Radiofrequency Ablation TherapyCOMPUTER GRAPHICS FORUM, Issue 3 2010Christian Rieder Abstract Percutaneous radiofrequency (RF) ablation is a minimally invasive, image-guided therapy for the treatment of liver tumors. The assessment of the ablation area (coagulation) is performed to verify the treatment success as an essential part of the therapy. Traditionally, pre- and post-interventional CT images are used to visually compare the shape, size, and position of tumor and coagulation. In this work, we present a novel visualization as well as a navigation tool, the so-called tumor map. The tumor map is a pseudo-cylindrical mapping of the tumor surface onto a 2D image. It is used for a combined visualization of all ablation zones of the tumor to allow a reliable therapy assessment. Additionally, the tumor map serves as an interactive tool for intuitive navigation within the 3D volume rendering of the tumor vicinity as well as with familiar 2D viewers. [source] Characterizing Core and Corridor Use by Nubian Ibex in the Negev Desert, IsraelCONSERVATION BIOLOGY, Issue 1 2000Yehoshua Shkedy To identify and characterize corridors used by Nubian ibex (Capra ibex nubiana), we analyzed sighting data recorded for the past 20 years in the Israel Nature Reserves Authority data banks. We categorized each recorded sighting as belonging to a corridor or a core zone based on the total number of sightings in its vicinity. We identified three main core populations, a natural corridor connecting two of them, and a corridor that was not evident connecting the third population. Ibex inside and outside core zones were sighted on steeper terrain than expected by chance; this was more pronounced inside the core zones than outside them. We hypothesize that because ibex outside core zones must move rapidly and directionally across unfamiliar habitats, they must use more moderate terrain. Although ibex sightings in core zones were mostly in the vicinity of water, we found no relationship between the location of the sightings and proximity to water sources in the corridor. Hence, water does not appear to be an important factor in movement through corridors. It was more common to observe ibex out of the core zones during the summer. Males, which can be twice the size of females, were found traveling alone in corridors more often than in core zones. There was no difference between males and females in the steepness of terrain in which they were sighted outside core zones. Our data show that protecting ibex habitat in core zones and corridors is important to ibex conservation in Israel's arid zones. In addition, protecting this habitat may benefit other rock-dwelling species in the area. Resumen: Los corredores son un factor clave en esfuerzos de conservación. Para identificar y caracterizar el uso de corredores por el íbice de Nubia (Capra ibex nubiana) analizamos datos de avistamiento de los últimos 20 años en las bases de datos de la Autoridad Israelí de Reservas Naturales. Categorizamos cada registro asignándolo a un corredor o a una zona núcleo basándonos en el total de registros cercanos. Identificamos tres poblaciones en zona núcleo, un corredor natural que conectaba a dos de ellas y un corredor, no muy evidente, conectando a la tercera población. Se registraron íbices en terrenos inclinados dentro y fuera de zonas núcleo más de lo esperado al azar; esto fue más marcado dentro de las zonas núcleo que afuera. Hipotetizamos que deben utilizar terrenos más moderados, debido a que los íbices fuera de las zonas núcleo deben moverse rápida y direccionalmente a través de hábitats no familiares. Aunque los registros de íbices en zonas núcleo estuvieron cercanos a agua, no encontramos relación entre la localización de los registros y la cercanía a fuentes de agua en el corredor. Por tanto, el agua no parece ser un factor importante en el movimiento en los corredores. Fue más común observar íbices afuera de las zonas núcleo en el verano. Los machos, que pueden ser dos veces más grandes que hembras, fueron registrados desplazándose solos en los corredores más a menudo que en las zonas núcleo. No hubo diferencia entre machos y hembras en la pendiente del terreno en que fueron registrados fuera de las zonas núcleo. Nuestros resultados indican que la protección del hábitat de íbices en zonas núcleo y corredores es importante para la conservación de íbices en las zonas áridas de Israel. Además, la protección de este hábitat puede beneficiar a otras especies en el área. [source] DOES SMALL DAM REMOVAL AFFECT LOCAL PROPERTY VALUES?CONTEMPORARY ECONOMIC POLICY, Issue 2 2008AN EMPIRICAL ANALYSIS This paper uses hedonic analysis to examine the impact of small dam removal on property values in south-central Wisconsin. Data on residential property sales were obtained for three categories of sites: those where a small dam remains intact, those where a small dam was removed, and those where a river or stream has been free-flowing for at least 20 yr. The primary conclusions that emerge from the data are that shoreline frontage along small impoundments confers no increase in residential property value compared to frontage along free-flowing streams and that nonfrontage residential property located in the vicinity of a free-flowing stream is more valuable than similar nonfrontage property in the vicinity of a small impoundment. (JEL Q2, Q25, Q5, Q51) [source] TOGp regulates microtubule assembly and density during mitosis and contributes to chromosome directional instabilityCYTOSKELETON, Issue 8 2009Lynne Cassimeris Abstract TOGp, a member of the XMAP215 MAP family, is required for bipolar mitotic spindle assembly. To understand how TOGp contributes to spindle assembly, we examined microtubule dynamics after depleting TOGp by siRNA. Fluorescence recovery after photobleaching of GFP-tubulin demonstrated that spindle microtubule turnover is slowed two-fold in the absence of TOGp. Consistent with photobleaching results, microtubule regrowth after washout of the microtubule depolymerizing drug nocodazole was slower at the centrosomes and in the vicinity of mitotic chromatin in cells depleted of TOGp. The slower microtubule turnover is likely due to either nucleation or the transitions of dynamic instability because TOGp depletion did not effect the rate of plus end growth, measured by tracking EB1-GFP at microtubule ends. In contrast, microtubule regrowth after nocodazole washout was unaffected by prior depletion of TACC3, a centrosomal protein that interacts with TOGp. Kinetochore fibers in both untreated and TOGp-depleted cells were stable to incubation at 4°C or lysis in buffer containing calcium indicating that stable kinetochore-microtubule attachments are formed in the absence of TOGp. Depletion of TOGp, but not TACC3, reduced kinetochore oscillations during prometaphase/metaphase. Defects in oscillations are not due simply to multipolarity or loss of centrosome focus in the TOGp-depleted cells, since kinetochore oscillations appear normal in cells treated with the proteosome inhibitor MG132, which also results in multipolar spindles and centrosome fragmentation. We hypothesize that TOGp is required for chromosome motility as a downstream consequence of reduced microtubule dynamics and/or density. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] In-Transit Metastasis From Primary Cutaneous Squamous Cell Carcinoma in Organ Transplant Recipients and Nonimmunosuppressed Patients: Clinical Characteristics, Management, and Outcome in a Series of 21 PatientsDERMATOLOGIC SURGERY, Issue 4p2 2004John A. Carucci MD Background. In-transit metastases from cutaneous squamous cell carcinoma (SCC) may occur in organ transplant recipients and may indicate aggressive disease and poor prognosis. Objective. The objective of this study was to describe in-transit metastases from cutaneous SCC and to identify factors associated with this phenomenon in a series of 21 patients. We also attempted to evaluate outcome with respect to status as an organ transplant recipient or nonorgan transplant recipient. Methods. A multicenter case series of patients was reviewed; factors included clinical presentation, management, and outcome. Results. Twenty-one patients, 15 organ transplant recipients, and 6 nontransplant recipients with in-transit metastases were reviewed. In-transit metastases presented most commonly as discrete, dermal papules distinct from but in the vicinity of the primary tumor site. Histologic differentiation was variable. At a mean follow up of 24 months, 33% the transplant patients had no evidence of disease compared with 80% of nontransplant patients. Thirty-three percent were dead from disease and 33% were alive with nodal or distant metastases. In contrast, 80% of nonimmunosuppressed patients had no evidence of disease and none had died at mean follow-up of 24 months. Conclusion. In-transit metastasis from cutaneous SCC is a unique presentation of metastatic SCC, more commonly described in organ transplant recipients, and is associated with poor prognosis in that group. This description represents the largest experience with in-transit metastases from cutaneous SCC in the literature. [source] Efficacy of the Flashlamp-Pumped Pulsed-Dye Laser in Nonsurgical Delay of Skin FlapsDERMATOLOGIC SURGERY, Issue 7 2003Ali Riza Erçöçen MD Objective. The purpose of this article was to determine the effectiveness of laser delay by use of the flashlamp-pumped pulsed-dye laser operating at a wavelength of 585 nm; to elucidate the comparable or dissimilar macroscopic, microscopic, and hemodynamic changes between laser and surgical delay methods; and to clarify the possible mechanisms underlying the delay effect of laser. Methods. A standardized caudally based random dorsal rat flap model was used in this study: Acute random skin flaps served as control subjects (group 1). Surgical delay was employed by incision of lateral longitudinal borders both without (group 2) and with (group 3) undermining, and laser delay methods were performed by laser irradiation of both lateral longitudinal borders (group 4) and the entire surface (group 5) of the proposed flap. Evaluation was done by histologic examination, India ink injection, laser Doppler perfusion imaging, and measurement of flap survival. Results. Histologically, dilation and hypertrophy of subpapillary and subdermal vessels were evident in groups 2, 3, and 4; on the other hand, degranulation of mast cells in the vicinity of occluded vessels at the 1st hour of laser delay and a striking mast cell proliferation and degranulation in association with newly formed vessels (angiogenesis) at the 14th day of laser delay were prominent in group 5. India ink injections revealed longitudinally arranged large-caliber vessels and cross-filling between the vessels of adjacent territories in groups, 2, 3, and 4, but only small-caliber vessels in group 5. Compared with the acute flaps, both surgical and laser delay significantly increased the mean flap perfusion to the maximal levels after a 14-day delay period, and all delay procedures improved flap survival; the most significant increase in surviving area was observed in group 3, whereas the less significant increase in surviving area was in group 5. Conclusion. This study demonstrates that laser delay is as effective as surgical delay and that laser delay by lasering lateral borders leads to dilation and longitudinal rearrangement of the existing vessels rather than angiogenesis, whereas laser delay by lasering the entire surface results in delay effect by inducing angiogenesis due to activation and degranulation of the mast cells. [source] Postembryonic development of the cranial lateral line canals and neuromasts in zebrafishDEVELOPMENTAL DYNAMICS, Issue 3 2003Jacqueline F. Webb Abstract The development of the cranial lateral line canals and neuromast organs are described in postembryonic zebrafish (0,80 days postfertilization). Cranial canal development commences several weeks after hatch, is initiated in the vicinity of individual neuromasts, and occurs in four discrete stages that are described histologically. Neuromasts remain in open canal grooves for several weeks during which they dramatically change shape and increase in size by adding hair cells at a rate one-tenth that in the zebrafish inner ear. Scanning electron microscopy demonstrates that neuromasts elongate perpendicular to the canal axis and the axis of hair cell polarization and that they lack a prominent nonsensory cell population surrounding the hair cells,features that make zebrafish neuromasts unusual among fishes. These results demand a reassessment of neuromast and lateral line canal diversity among fishes and highlight the utility of the lateral line system of postembryonic zebrafish for experimental and genetic studies of the development and growth of hair cell epithelia. Developmental Dynamics, 2003. © 2003 Wiley-Liss, Inc. [source] Developmental changes in neurite outgrowth responses of dorsal root and sympathetic ganglia to GDNF, neurturin, and arteminDEVELOPMENTAL DYNAMICS, Issue 3 2003H. Yan Abstract The ability of glial cell line,derived neurotrophic factor (GDNF), neurturin, and artemin to induce neurite outgrowth from dorsal root, superior cervical, and lumbar sympathetic ganglia from mice at a variety of development stages between embryonic day (E) 11.5 and postnatal day (P) 7 was examined by explanting ganglia onto collagen gels and growing them in the presence of agarose beads impregnated with the different GDNF family ligands. Artemin, GDNF, and neurturin were all capable of influencing neurite outgrowth from dorsal root and sympathetic ganglia, but the responses of each neuron type to the different ligands varied during development. Neurites from dorsal root ganglia responded to artemin at P0 and P7, to GDNF at E15.5 and P0, and to neurturin at E15.5, P0, and P6/7; thus, artemin, GDNF, and neurturin are all capable of influencing neurite outgrowth from dorsal root ganglion neurons. Neurites from superior cervical sympathetic ganglia responded significantly to artemin at E15.5, to GDNF at E15.5 and P0, and to neurturin at E15.5. Neurites from lumbar sympathetic ganglia responded to artemin at all stages from E11.5 to P7, to GDNF at P0 and P7 and to neurturin at E11.5 to P6/7. Combined with the data from previous studies that have examined the expression of GDNF family members, our data suggest that artemin plays a role in inducing neurite outgrowth from young sympathetic neurons in the early stages of sympathetic axon pathfinding, whereas GDNF and neurturin are likely to be important at later stages of sympathetic neuron development in inducing axons to enter particular target tissues once they are in the vicinity or to induce branching within target tissues. Superior cervical and lumbar sympathetic ganglia showed temporal differences in their responsiveness to artemin, GDNF, and neurturin, which probably partly reflects the rostrocaudal development of sympathetic ganglia and the tissues they innervate. Developmental Dynamics 227:395,401, 2003. © 2003 Wiley-Liss, Inc. [source] Vascular regression is required for mesenchymal condensation and chondrogenesis in the developing limbDEVELOPMENTAL DYNAMICS, Issue 3 2001Melinda Yin Abstract Vascular regression occurs during limb mesenchymal cell condensation and chondrogenesis, but it is unclear whether it is required for these processes or is a secondary phenomenon without major regulatory roles. To address this issue, beads presoaked with the potent angiogenic factor vascular endothelial growth factor (VEGF) were implanted in the vicinity of the prospective digit 2 in early chick embryo wing buds and the effects on angiogenesis and digit development were determined over time. We found that VEGF treatment caused a marked local increase in blood vessel number and density. Strikingly, this was accompanied by inhibition of digit 2 development as revealed by lack of expression of chondrogenic transcription factor Sox9 and absence of Alcian blue staining. Vascular distribution and skeletal development in adjacent areas remained largely unaffected. Inhibition of digit formation and excess vascularization were both reversible upon further embryonic growth and dissipation of VEGF activity. When supernumerary digits were induced at the anterior limb margin by retinoic acid treatment, their development was also preceded by vascular regression; interestingly, cotreatment with VEGF inhibited supernumerary digit development as well. Direct exposure of limb mesenchymal cells in micromass cultures to VEGF caused no obvious effects on condensation and chondrogenesis, indicating that VEGF effects are not due to direct action on skeletal cells. Our results are the first to provide evidence that vascular regression is required for mesenchymal condensation and chondrogenesis. A model of how patterning mechanisms and vascular regression may intersect and orchestrate limb skeletogenesis is proposed. © 2001 Wiley-Liss, Inc. [source] Early and transient ontogenetic expression of the cocaine- and amphetamine-regulated transcript peptide in the rat mesencephalon: Correlation with tyrosine hydroxylase expressionDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2002F. Brischoux Abstract The ontogeny of cocaine- and amphetamine-regulated transcript (CART) expression has been analyzed by immunohistochemistry in the mesencephalon of the rat central nervous system, and compared to the pattern of tyrosine hydroxylase- (TH-) expression. CART-producing neurons were first detected on the embryonic day 11 (E11) in the ventral mesencephalic vesicle. These neurons are among the first cells of the mantle layer to differentiate. From E13, a complementary pattern of distribution was observed, dividing the mantle layer into an external TH zone and an internal CART zone. Many TH-positive neurons were found to migrate from the neuroepithelium through the area containing the CART-immunoreactive neurons to settle more laterally. These TH cells exhibited prominent leading and trailing dendrites in the immediate vicinity of CART perikarya. On E16, the number of CART neurons appeared to diminish, and they were confined near the ventricle and around the fasciculus retroflexus. On E18 and E20, only the Edinger-Westphal nucleus exhibited a strong CART staining as described in the adult brain. Thus, the very early detection of CART during prenatal ontogeny led us to speculate that this peptide might have a role in the development of specific regions of the rat brain. In particular, our observations suggest that CART-expressing neurons might help the migration of the dopaminergic neurons of the substantia nigra. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 221,229, 2002 [source] Spermatogenesis in Boccardiella hamata (Polychaeta: Spionidae) from the Sea of Japan: sperm formation mechanisms as characteristics for future taxonomic revisionACTA ZOOLOGICA, Issue 4 2010Arkadiy A. Reunov Abstract Reunov, A.A., Yurchenko, O.V., Alexandrova, Y.N. and Radashevsky, V.I. 2009. Spermatogenesis in Boccardiella hamata (Polychaeta: Spionidae) from the Sea of Japan: sperm formation mechanisms as characteristics for future taxonomic revision. ,Acta Zoologica (Stockholm) 91: 477,456. To characterize novel features that will be useful in the discussion and validation of the spionid polychaete Boccardiella hamata from the Sea of Japan, the successive stages of spermatogenesis were described and illustrated. Spermatogonia, spermatocytes and early spermatids are aflagellar cells that develop synchronously in clusters united by a cytophore. At the middle spermatid stage, the clusters undergo disintegration and spermatids produce flagella and float separately in coelomic fluid as they transform into sperm. Spermatozoa are filiform. The ring-shaped storage platelets are located along the anterior nuclear area. The nucleus is cupped by a conical acrosome. A nuclear plate is present between the acrosome and nucleus. The nucleus is a cylinder with the implantation fossa throughout its length and with the anterior part of the flagellum inside the fossa. There is only one centriole, serving as a basal body of the flagellum, situated in close vicinity of the acrosomal area. A collar of four mitochondria is located under the nuclear base. The ultrastructure of B. hamata spermatozoa from the Sea of Japan appears to be close to that of B. hamata from Florida described by Rice (Microscopic Anatomy of Invertebrates, Wiley-Liss, Inc., New York, 1992), suggesting species identity of the samples from the two regions. However, more detailed study of Florida's B. hamata sperm is required for a reliable conclusion concerning the similarity of these two polychaetes. In addition to sperm structure, features such as the cytophore-assigned pattern of spermatogenic cell development, the synchronous pattern of cell divisions, the non-flagellate early spermatogenic stages, and the vesicle amalgamation that drives meiotic cell cytokinesis and spermatid diorthosis will likely be useful in future testing of the validity of B. hamata and sibling species throughout the world. [source] Spatial autocorrelation of assemblages of benthic invertebrates and its relationship to environmental factors in two upland rivers in southeastern AustraliaDIVERSITY AND DISTRIBUTIONS, Issue 5 2005Natalie J. Lloyd ABSTRACT The nature of spatial autocorrelation of biota may reveal much about underlying ecological and biological factors responsible for producing those patterns, especially dispersal processes (drift, adult flight, etc.). We report here on assemblage-level autocorrelation in the benthic-invertebrate assemblages (retained in sieves of 300 µm mesh) of riffles in two adjacent, relatively pristine rivers in southeastern Victoria, Australia (40-km reaches of the Wellington and Wonnangatta Rivers). These are related to patterns of autocorrelation in physical and catchment conditions (,environmental variables') in the vicinity of the sampling points. Both the invertebrate assemblages and environmental variables were autocorrelated at small scales (= 8 km) in the Wellington River in one of the sampling years (1996). Dissimilarities of invertebrate assemblages were correlated with dissimilarities of environmental variables in both sampling years (1996 and 1997) in that river. Environmental variables were autocorrelated in the Wonnangatta River, but this was not expressed as autocorrelation in the assemblages of invertebrates, which were not autocorrelated at any scale studied. Individual environmental variables showed different spatial patterns between the two rivers. These results suggest that individual rivers have their own idiosyncratic patterns and one cannot assume that even similar, geographically adjacent rivers will have the same patterns, which is a difficulty for ecological assessment and restoration. [source] Characteristics and dynamics of multiple intertidal bars, north Lincolnshire, EnglandEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2006Selma van Houwelingen Abstract Multiple intertidal bars and troughs, often referred to as ,ridges and runnels', are significant features on many macrotidal sandy beaches. Along the coastline of England and Wales, they are particularly prevalent in the vicinity of estuaries, where the nearshore gradient is gentle and a large surplus of sediment is generally present. This paper examines the dynamics of such bar systems along the north Lincolnshire coast. A digital elevation model of the intertidal morphology obtained using LIDAR demonstrates that three to five intertidal bars are consistently present with a spacing of approximately 100 m. The largest and most pronounced bars (height = 0·5,0·8 m) are found around mean sea level, whereas the least developed bars (height = 0·2,0·5 m) occur in the lower intertidal zone. Annual aerial photographs of the intertidal bar morphology were inspected to try to track individual bars from year to year to derive bar migration rates; however, there is little resemblance between concurrent photographs, and ,resetting' of the intertidal profile occurs on an annual basis. Three-dimensional beach surveys were conducted monthly at three locations along the north Lincolnshire coast over a one-year period. The intertidal bar morphology responds strongly to the seasonal variation in the forcing conditions, and bars are least numerous and flattest during the more energetic winter months. Morphological changes over the monthly time scale are strongly affected by longshore sediment transport processes and the intertidal bar morphology can migrate along the beach at rates of up to 30 m per month. The behaviour of intertidal bars is complex and varies over a range of spatial and temporal scales in response to a combination of forcing factors (e.g. incident wave energy, different types of wave processes, longshore and cross-shore sediment transport), relaxation time and morphodynamic feedback. Copyright © 2005 John Wiley & Sons, Ltd. [source] Semi-empirical model for site effects on acceleration time histories at soft-soil sites.EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2004Part 1: formulation, development Abstract A criterion is developed for the simulation of realistic artificial ground motion histories at soft-soil sites, corresponding to a detailed ground motion record at a reference firm-ground site. A complex transfer function is defined as the Fourier transform of the ground acceleration time history at the soft-soil site divided by the Fourier transform of the acceleration record at the firm-ground site. Working with both the real and the imaginary components of the transfer function, and not only with its modulus, serves to keep the statistical information about the wave phases (and, therefore, about the time variation of amplitudes and frequencies) in the algorithm used to generate the artificial records. Samples of these transfer functions, associated with a given pair of soft-soil and firm-ground sites, are empirically determined from the corresponding pairs of simultaneous records. Each function included in a sample is represented as the superposition of the transfer functions of the responses of a number of oscillators. This formulation is intended to account for the contributions of trains of waves following different patterns in the vicinity of both sites. The properties of the oscillators play the role of parameters of the transfer functions. They vary from one seismic event to another. Part of the variation is systematic, and can be explained in terms of the influence of ground motion intensity on the effective values of stiffness and damping of the artificial oscillators. Another part has random nature; it reflects the random characteristics of the wave propagation patterns associated with the different events. The semi-empirical model proposed recognizes both types of variation. The influence of intensity is estimated by means of a conventional one-dimensional shear wave propagation model. This model is used to derive an intensity-dependent modification of the values of the empirically determined model parameters in those cases when the firm-ground earthquake intensity used to determine these parameters differs from that corresponding to the seismic event for which the simulated records are to be obtained. Copyright © 2004 John Wiley & Sons, Ltd. [source] Spatial pattern of adult trees and the mammal-generated seed rain in the Iberian pearECOGRAPHY, Issue 3 2010Jose M. Fedriani The degree to which plant individuals are aggregated or dispersed co-determines how a species uses resources, how it is used as a resource, and how it reproduces. Quantifying such spatial patterns, however, presents several methodological issues that can be overcome by using spatial point pattern analyses (SPPA). We used SPPA to assess the distribution of P. bourgaeana adult trees and their seeds (within fecal samples) dispersed by three mammals (badger, fox, and wild boar) within a 72-ha plot across a range of spatial scales. Pyrus bourgaeana trees in our study plot (n=75) were clearly aggregated with a critical spatial scale of ca 25,m, and approximately nine randomly distributed tree clusters were identified. As expected from their marking behaviors, the spatial patterns of fecal deposition varied widely among mammal species. Whereas badger feces and dispersed seeds were clearly clustered at small spatial scales (<10,m), boar and fox feces were relatively scattered across the plot. A toroidal shift null model testing for independence indicated that boars tended to deliver seeds to the vicinity of adult trees and thus could contribute to the maintenance and enlargement of existing tree clusters. Badgers delivered feces and seeds in a highly clumped pattern but unlike boars, away from P. bourgaeana neighborhoods; thus, they are more likely to create new tree clusters than boars. The strong tree aggregation is likely to be the result of one or several non-exclusive processes, such as the spatial patterning of seed delivery by dispersers and seedling establishment beneath mother trees. In turn, the distinctive distribution of P. bourgaeana in Doñana appeared to interact with the foraging behavior of its mammalian seed dispersers, leading to neighbourhood-specific dispersal patterns and fruit-removal rates. Our study exemplifies how a detailed description of patterns generates testable hypotheses concerning the ecology of zoochorous. Pyrus bourgaeana dispersers were unique and complementary in their spatial patterning of seed delivery, which likely confers resilience to their overall service and suggests lack of redundancy and expendability of any one species. [source] | ||||||||||||||||||||||||||||||||||||||||||||||