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Widening
Kinds of Widening Terms modified by Widening Selected AbstractsBeyond the Customs Union: The European Community's Quest for Deepening, Widening and Completion, 1969,75 , Edited by J. Van Der HarstJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 4 2008LUIS SIMON No abstract is available for this article. [source] Brugada-Type ECG Pattern and Extreme QRS Complex Widening with Propafenone OverdoseJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2006CAN HASDEMIR M.D. [source] The pathology of chronic erosive dermatopathy in Murray cod, Maccullochella peelii peelii (Mitchell)JOURNAL OF FISH DISEASES, Issue 1 2005J E Baily Abstract Chronic erosive dermatopathy (CED) is a disease of intensively farmed Murray cod in Australia that has been reported in association with the use of groundwater (mechanically extracted from shallow boreholes) supplies. CED results in focal ulceration of the skin overlying sensory canals of the head and flanks. Trials were conducted at an affected fish farm to study the development of the condition, both in Murray cod and in goldfish, and also to assess the reported recovery of lesions when affected fish were transferred to river water. Grossly, lesions began after 2,3 weeks with degeneration of tissue at the periphery of pores communicating with the sensory canals. Widening of these pores along the axis of the canals resulted from a loss of tissue covering the canal. Histopathologically, hyperplasia of the canal epithelial lining was seen after 3 weeks in borehole water and subsequent necrosis and sloughing of this tissue resulted in the loss of the canal roof. Canal regeneration occurred when fish were transferred from borehole water into river water. The lack of lesions in other organs and the pattern of lesion development support exposure to waterborne factors as the most likely aetiology. [source] Observation of rapid drainage system development by thermal erosion of ice wedges on Bylot Island, Canadian Arctic ArchipelagoPERMAFROST AND PERIGLACIAL PROCESSES, Issue 3 2007Daniel Fortier Abstract Rapid development of a new drainage system was observed on Bylot Island. A 750-m long gully system was eroded in four years. The process was initiated by the formation of sinkholes eroded in ice wedges by runoff flowing into open frost cracks. The sinkholes evolved into underground tunnels cut in the ice-wedge network and the ice-rich permafrost. Widening of tunnels was followed by subsidence and collapse of their roofs and the development of open gullies. The drainage generally developed as the shortest line along the regional slope with some deviations caused by collapse of blocks of soil which temporarily obstructed the water flow. Retrogressive scarps exposed to flowing water retreated at maximum rates of up to 5,m/day for a total of 15 to 50,m during the summer. Scarps exposed to atmospheric heat and solar radiation retreated between 2.5 and 40,m over four summers with a mean of 15.5,m. Such slopes had nearly stabilised after four years with a retreat rate of only a few centimetres per year in the last year of observation. Copyright © 2007 John Wiley & Sons, Ltd. [source] The Effect of Full-Face Broadband Light Treatments Alone and in Combination With Bilateral Crow's Feet Botulinum Toxin Type A ChemodenervationDERMATOLOGIC SURGERY, Issue 3 2004Jean Carruthers MD Background. Broadband light (BBL; Intense Pulsed Light; Lumenis Ltd., Yokneam, Israel) is a powerful, nonablative, light-based technology that targets melanin and hemoglobin and stimulates the formation of collagen and elastin. Botulinum toxin type A (BTX-A; BOTOX; Allergan Inc., Irvine, CA) treatment of the lateral periocular region relaxes the vertical fibers of the orbicularis oculi and results in softening of the lateral orbital crow's feet rhytides and widening of the palpebral aperture. Objective. To compare the effects of full-face BBL in combination with BTX-A and BBL alone in female subjects with Fitzpatrick I,III skin types, Glogau II,III rhytides, and significant associated facial lentigines and telangiectasia. Methods. This was a prospective, randomized study of 30 women with moderate to severe crow's feet rhytides. Half of the subjects were treated with BTX-A and BBL and the other half with BBL alone. Their response was assessed clinically and photographically. Skin biopsies of the temporal skin were taken from two subjects in each group and were stained with Masson trichrome. Results. Patients treated with a combination of BTX-A and BBL experienced a better response to treatment, both at rest and on maximum smile, as well as a slightly improved response in associated lentigines, telangiectasia, pore size, and facial skin texture compared with patients who received BBL treatment alone. Skin biopsies showed an increase in dermal collagen in each group. Conclusions. The patients in this study benefited from both treatments. Although BBL led to a remarkable improvement in full-face telangiectasias, lentigines, and skin texture, the improvement increased in all categories with combination therapy. In addition, an added improvement in the full-face aesthetic with both BTX-A and BBL therapy combined was obvious. These results suggest that both treatments,although evidently complementary,may also act synergistically to produce optimal clinical effects, revolutionizing the treatment of facial aging. [source] Ingrown and pincer nails: evaluation and treatmentDERMATOLOGIC THERAPY, Issue 2 2002E. Haneke Ingrown toenails are mainly a condition of children and young adults, whereas ingrown fingernail and pincer nails are seen in adults. Their etiology is multifactorial. Different types of ingrowing nails require different treatments. Neonatal ones are always treated conservatively. The hypertrophic lateral nail wall seldom requires surgery. Congenital misalignment of the big toenail may resolve spontaneously, but delay in treatment may cause permanent nail dystrophy. The juvenile type is most common and is treated conservatively in its early stages. Selective matrix horn phenolization or excision is the treatment of choice for later stages. Pincer nails are due to widening of the base of the distal phalanx. Treatment is aimed at reducing the outward pressure of the lateral osteophytes on the matrix horns and permanently flattening the nail. A variety of different methods are discussed. [source] Flow energy and channel adjustments in rills developed in loamy sand and sandy loam soilsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 1 2009Jovan R. Stefanovic Abstract The storms usually associated with rill development in nature are seldom prolonged, so development is often interrupted by interstorm disturbances, e.g. weathering or tillage. In laboratory simulated rainfall experiments, active rill development can be prolonged, and under these conditions typically passes through a period of intense incision, channel extension and bifurcation before reaching quasi-stable conditions in which little form change occurs. This paper presents laboratory experiments with coarse textured soils under simulated rainfall which show how channel adjustment processes contribute to the evolution of quasi-stability. Newly incised rills were stabilized for detailed study of links between rill configuration and flow energy. On a loamy sand, adjustment towards equilibrium occurred due to channel widening and meandering, whereas on a sandy loam, mobile knickpoints and chutes, pulsations in flow width and flow depth and changes in stream power and sediment discharge occurred as the channel adjusted towards equilibrium. The tendency of rill systems towards quasi-stability is shown by changes in stream power values which show short-lived minima. Differences in energy dissipation in stabilized rills indicate that minimization of energy dissipation was reached locally between knickpoints and at the downstream ends of rills. In the absence of energy gradients in knickpoints and chutes, stabilized rill sections tended toward equilibrium by establishing uniform energy expenditure. The study confirmed that energy dissipation increased with flow aspect ratio. In stabilized rills, flow acceleration reduced energy dissipation on the loamy sand but not on the sandy loam. On both soils flow deceleration tended to increase energy dissipation. Understanding how rill systems evolve towards stability is essential in order to predict how interruptions between storms may affect long-term rill dynamics. This is essential if event-based physical models are to become effective in predicting sediment transport on rilled hillslopes under changing weather and climatic conditions. Copyright © 2008 John Wiley and Sons, Ltd. [source] Modelling the effect of form and profile adjustments on channel equilibrium timescalesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 12 2003Martin W. Doyle Abstract A model for describing river channel pro,le adjustments through time is developed and applied to a river responding to base-level lowering in order to examine the effect of channel widening and downstream aggradation on equilibrium timescales. Across a range of boundary conditions, downstream aggradation controlled how quickly a channel reached equilibrium. Channel widening either increased or decreased the equilibrium timescale, depending on whether or not sediment derived from widening was deposited downstream. Results suggest that pro,le adjustments are more important than channel width adjustments in controlling equilibrium timescales for a channel responding to base-level lowering. Copyright © 2003 John Wiley & Sons, Ltd. [source] Processes and forms of an unstable alluvial system with resistant, cohesive streambeds ,EARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2002Andrew Simon Abstract As a response to channelization projects undertaken near the turn of the 20th century and in the late 1960s, upstream reaches and tributaries of the Yalobusha River, Mississippi, USA, have been rejuvenated by upstream-migrating knickpoints. Sediment and woody vegetation delivered to the channels by mass failure of streambanks has been transported downstream to form a large sediment/debris plug where the downstream end of the channelized reach joins an unmodified sinuous reach. Classification within a model of channel evolution and analysis of thalweg elevations and channel slopes indicates that downstream reaches have equilibrated but that upstream reaches are actively degrading. The beds of degrading reaches are characterized by firm, cohesive clays of two formations of Palaeocene age. The erodibility of these clay beds was determined with a jet-test device and related to critical shear stresses and erosion rates. Repeated surveys indicated that knickpoint migration rates in these clays varied from 0·7 to 12 m a,1, and that these rates and migration processes are highly dependent upon the bed substrate. Resistant clay beds of the Porters Creek Clay formation have restricted advancement of knickpoints in certain reaches and have caused a shift in channel adjustment processes towards bank failures and channel widening. Channel bank material accounts for at least 85 per cent of the material derived from the channel boundaries of the Yalobusha River system. Strategies to reduce downstream flooding problems while preventing upstream erosion and land loss are being contemplated by action agencies. One such proposal involves removal of the sediment/debris plug. Bank stability analyses that account for pore-water and confining pressures have been conducted for a range of hydrologic conditions to aid in predicting future channel response. If the sediment/debris plug is removed to improve downstream drainage, care should be taken to provide sufficient time for drainage of groundwater from the channel banks so as not to induce accelerated bank failures. Published in 2002 John Wiley & Sons, Ltd. [source] Direct observation of frost wedging in alpine bedrockEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2001Norikazu Matsuoka Abstract Width and temperature of rock joints were automatically monitored in the Japanese Alps. Three years of monitoring on a sandstone rock face shows two seasonal peaks of joint widening in autumn and spring. The autumn events are associated with short-term freeze,thaw cycles, and the magnitude of widening reflects the freezing intensity and water availability. The short-term freezing can produce wedging to a depth of at least 20,cm. The spring events follow a rise in the rock surface temperature to 0,°C beneath the seasonal snowcover, and likely originate from refreezing of meltwater entering the joint. Some of these events contribute to permanent enlargement of the joint. Two other joints on nearby rock faces experience only sporadic widening accompanying freeze,thaw cycles and insignificant permanent enlargement. Observations indicate that no single thermal criterion can explain frost weathering. The temperature range at which wedging occurs varies with the bedrock conditions, water availability and duration of freezing. Copyright © 2001 John Wiley & Sons, Ltd. [source] Wolves, trophic cascades, and rivers in the Olympic National Park, USAECOHYDROLOGY, Issue 2 2008Robert L. Beschta Abstract Gray wolves (Canis lupus) were extirpated in the early 1900s from the Olympic Peninsula of northwestern Washington. Thus, we studied potential cascading effects of wolf removal by undertaking a retrospective study of Roosevelt elk (Cervus elaphus) populations, riparian forests, and river channel morphology. For three riparian sites within the western portion of Olympic National Park, the age structure of black cottonwood and bigleaf maple indicated a pattern of significantly decreased recruitment (growth of seedlings/sprouts into tall saplings and trees) associated with intensive elk browsing in the decades following the loss of wolves. At a riparian site outside the park, which represented a refugium from elk browsing, cottonwood recruitment has been ongoing during the 20th century, indicating that climate and flow regimes, in the absence of intensive herbivory, have not limited the establishment and growth of this deciduous woody species. Using 1994 orthophotos, we also measured channel dimensions and planform morphology of 8-km-long river reaches at each vegetation sampling site and an additional reach outside the park. Channels inside the park versus those outside the park had greater percent braiding (37 vs 2%) and larger ratios of active channel width/wetted width (3·0 vs 1·5 m/m). Results for western Olympic National Park were consistent with a truncated trophic cascade hypothesis whereby ungulate browsing following the extirpation of wolves caused significant long-term impacts to riparian plant communities which, in turn, allowed increased riverbank erosion and channel widening to occur. Copyright © 2008 John Wiley & Sons, Ltd. [source] Structural myocardial changes after coronary artery surgeryEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 11 2000F. Eberhardt Background Postoperative contractile dysfunction or ,myocardial stunning' has been described after coronary artery bypass grafting (CABG). In the present study we sought to determine if and to what extent clinical, structural and histochemical evidence of myocardial changes associated with stunning could be found in patients after CABG and cold crystalloid cardioplegia. Materials and methods Left ventricular (LV) biopsies were obtained from CABG patients (n = 10) prior to and at the end of cardiopulmonary bypass (CPB). These biopsies were immunostained for the inducible heat-shock protein 70 (HSP-70i), intercellular adhesion molecule-1 (ICAM-1) and actin. ATP was measured by bioluminescence. Results Biopsies pre-CPB showed no evidence of myocardial damage as HSP-70i was absent and a regular actin cross-striation pattern and only constitutive ICAM-1-expression were present. After CPB we found significantly increased HSP-70i and ICAM-1 levels as well as a deranged actin cross-striation pattern with a widening of actin bands. ATP levels declined from 10 mmol L,1 pre-CPB to 4.9 mmol L,1 after CPB. Correspondingly, coronary sinus effluent showed a significant lactate production. Although, cardiac function determined by transoesophageal echocardiography did not deteriorate, significant inotropic support was necessary to maintain cardiac output. Conclusions Our results present clinical and structural evidence of ,myocardial stunning' after CABG and cold crystalloid cardioplegia. Increased HSP-70i and ICAM-1 expression, as well as a deranged actin cross-striation pattern, might be structural markers to determine ,myocardial stunning' in clinical settings. [source] Impairment of binocular vision in the adult cat induces plastic changes in the callosal cortical mapEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2001Laurent Watroba Abstract In the primary visual cortex of normally reared adult cat, neurons activated through the corpus callosum are almost entirely located at the 17/18 border. They display small receptive fields distributed along the central vertical meridian of the visual field and are orientation selective. Here we demonstrate that a few weeks of monocular deprivation or unilateral convergent strabismus produced in adulthood does not modify the cortical distribution of these neurons, but leads to an increase of their receptive field size mainly toward the ipsilateral hemifield and to a loss of their orientation selectivity. We conclude that manipulation of binocular vision in the adult modifies neither the location of the primary callosal cortical map nor its retinotopy. In contrast, it induces functional plastic changes in this map which lead to a significant widening of the area of visual space signalled through the corpus callosum. These plastic changes are interpreted as the result of the strengthening of normally hidden subthreshold synaptic inputs. [source] Personality, creativity and latent inhibitionEUROPEAN JOURNAL OF PERSONALITY, Issue 2 2006Giles St J. Burch The current study set out to investigate the relationship between creativity, multi-dimensional schizotypy and personality more generally. This was achieved by analysing scores on a range of personality scales and measures of creativity, where it was found that the creativity measures were more closely related to asocial-schizotypy than positive-schizotypy. The study also sought to test Eysenck's prediction (1993, 1995) that, given the putative relationship between creativity and psychosis-proneness, high psychosis-prone scoring individuals and high creativity scoring individuals would demonstrate the same cognitive style of ,overinclusiveness' on latent inhibition. However, the results failed to demonstrate any evidence of a shared ,widening of the associative horizon' between high creativity and high psychosis-prone scorers. The findings are discussed in relation to multi-dimensional schizotypy. Copyright © 2006 John Wiley & Sons, Ltd. [source] Genotype,phenotype correlation in skin fragility-ectodermal dysplasia syndrome resulting from mutations in plakophilin 1EXPERIMENTAL DERMATOLOGY, Issue 2 2002T. Hamada Abstract: We report a 42-year-old Japanese man with an unusual autosomal recessive genodermatosis. The clinical features comprised normal skin at birth, loss of scalp hair at 3-months of age after a febrile illness, progressive nail dystrophy during infancy, palmoplantar keratoderma starting around the age of 18 years and trauma-induced skin fragility and blisters noted from the age of 20 years. Skin biopsy of rubbed non-lesional skin revealed widening of spaces between adjacent keratinocytes from the suprabasal layer upwards. Electron microscopy demonstrated a reduced number of hypoplastic desmosomes. Immunohistochemical labeling showed a reduction in intercellular staining for the desmosome component plakophilin 1. Mutation analysis revealed a homozygous intron 11 donor splice site mutation in the plakophilin 1 gene, 2021+1 G>A (GenBank no. Z34974). RT-PCR, using RNA extracted from the skin biopsy, provided evidence for residual low levels of the full-length wild-type transcript (,8%) as well as multiple other near full-length transcripts, one of which was in frame leading to deletion of 17 amino acids from the 9th arm-repeat unit of the plakophilin 1 tail domain. Thus, the molecular findings help explain the clinical features in the patient, who has a similar but milder phenotype to previously reported patients with skin fragility-ectodermal dysplasia syndrome associated with complete ablation of plakophilin 1 (OMIM 604536). This new ,mitis' phenotype provides further clinicopathological evidence for the role of plakophilin 1 in keratinocyte cell,cell adhesion and ectodermal development. [source] Physiological Society Symposium , the Athlete's HeartEXPERIMENTAL PHYSIOLOGY, Issue 5 2003Athlete's heart, effect of age, ethnicity, sporting discipline Regular physical training is associated with several physiological and biochemical adaptations which enable an increase in cardiac output and widening of the systemic arterio-venous oxygen difference. An increase in cardiac chamber size is fundamental to the generation of a sustained increase in cardiac output for prolonged periods. Echocardiographic studies have shown that the vast majority of athletes have modest cardiac enlargement although a small proportion exhibit substantial increases in heart size. Recognised determinants of cardiac size include age, sex, ethnicity and type of sport. Cardiac dimensions vary considerably amongst athletes, even when allowances are made for these variables, suggesting that genetic, endocrine and biochemical factors also influence heart size. This review discusses the effects of age, sex, ethnicity and sporting discipline on cardiac dimensions in athletic individuals. [source] Stratification in Higher Education, Choice and Social Inequalities in GreeceHIGHER EDUCATION QUARTERLY, Issue 1 2010Eleni Sianou-Kyrgiou Higher education has expanded to a remarkable extent in many countries in recent decades. Although this has led to high levels of participation, inequalities not only persist but are also strengthened. The persistence of inequalities is partly the result of policies for the widening of participation having been accompanied by institutional stratification with educational choices being unequal and socially defined. There is evidence that with the development of new university departments and the increase in the number of university entrants in Greece, a stratified system of higher education has emerged. This study draws on quantitative data that provides evidence that choice has been driven largely by the students' social class: the close relationship between social class and educational opportunities has remained intact. Furthermore, social inequalities in access and distribution in higher education persist, despite the substantial increase in participation in higher education. Social class is a key factor in the interpretation of choice of study, which, along with the performance in the national level examinations that determines entrance into universities, has also led to the increase in the stratification of higher education institutions. [source] SWAT2000: current capabilities and research opportunities in applied watershed modellingHYDROLOGICAL PROCESSES, Issue 3 2005J. G. Arnold Abstract SWAT (Soil and Water Assessment Tool) is a conceptual, continuous time model that was developed in the early 1990s to assist water resource managers in assessing the impact of management and climate on water supplies and non-point source pollution in watersheds and large river basins. SWAT is the continuation of over 30 years of model development within the US Department of Agriculture's Agricultural Research Service and was developed to ,scale up' past field-scale models to large river basins. Model components include weather, hydrology, erosion/sedimentation, plant growth, nutrients, pesticides, agricultural management, stream routing and pond/reservoir routing. The latest version, SWAT2000, has several significant enhancements that include: bacteria transport routines; urban routines; Green and Ampt infiltration equation; improved weather generator; ability to read in daily solar radiation, relative humidity, wind speed and potential ET; Muskingum channel routing; and modified dormancy calculations for tropical areas. A complete set of model documentation for equations and algorithms, a user manual describing model inputs and outputs, and an ArcView interface manual are now complete for SWAT2000. The model has been recoded into Fortran 90 with a complete data dictionary, dynamic allocation of arrays and modular subroutines. Current research is focusing on bacteria, riparian zones, pothole topography, forest growth, channel downcutting and widening, and input uncertainty analysis. The model SWAT is meanwhile used in many countries all over the world. Recent developments in European Environmental Policy, such as the adoption of the European Water Framework directive in December 2000, demand tools for integrative river basin management. The model SWAT is applicable for this purpose. It is a flexible model that can be used under a wide range of different environmental conditions, as this special issue will show. The papers compiled here are the result of the first International SWAT Conference held in August 2001 in Rauischholzhausen, Germany. More than 50 participants from 14 countries discussed their modelling experiences with the model development team from the USA. Nineteen selected papers with issues reaching from the newest developments, the evaluation of river basin management, interdisciplinary approaches for river basin management, the impact of land use change, methodical aspects and models derived from SWAT are published in this special issue. Copyright © 2005 John Wiley & Sons, Ltd. [source] Canal shapes produced sequentially during instrumentation with Quantec SC rotary nickel,titanium instruments: a study in simulated canalsINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2001I. T. Griffiths Abstract Aim The aim of this study was to determine the shaping ability of Quantec SC nickel,titanium rotary instruments in simulated root canals. Methodology Forty simulated canals consisting of four different shapes in terms of angle and position of curvature were prepared with Quantec SC instruments. Sequential still images were taken of the canals using a video camera attached to a computer with image analysis software. Images were taken preoperatively, and then after instrument 7 (Size 25, 0.05 taper), instrument 8 (size 25, 0.06 taper), and instrument 10 (size 45, 0.02 taper) were taken to length. Each sequential postoperative image was superimposed individually over the preoperative image in order to highlight the amount and position of material removed during preparation. Results Overall, the mean preparation time to size 10 was 3.6 min with 12 mm canals taking on average less time than 8 mm canals. There was a highly significant difference between the canal types (P < 0.0001). No instruments fractured within the canal or deformed, although one instrument separated from the latch grip. All canals remained patent. Following preparation to size 10, 19 canals (48%) retained their length, eight (20%) lost length, and 13 (32%) gained length; the magnitude of the change in length was always 0.5 mm or below. Following preparation to size 7 instruments all canals showed aberrant shapes. Excess removal of material along the outer aspect of the curve between the beginning of the curve and the end-point (outer widening) was found in 26 canals (65%) after instrument 7. At the same stage of preparation six canals (15%) had zips, three (8%) had ledges and five (13%) had perforations. Following preparation to size 10, 27 (68%) canals were perforated. Conclusions Under the conditions of the study, Quantec SC instruments consistently produced aberrations when canals were enlarged to size 7 (size 25, 0.05 taper) or above. Care should be exercised when using these instruments in real teeth. [source] Chronic telogen effluvium or early androgenetic alopecia?INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2004Rodney Sinclair MBBS A 16-year-old girl presented with a 12-month history of generalized hair shedding from the scalp. The onset of shedding coincided with the development of Hashimoto's thyroiditis and iron deficiency. At the time of initial presentation, the Hashimoto's thyroiditis had been treated with Neo-Mercazole and she was euthyroid. Her iron stores were low, with a ferritin level of 13 µg/L. As she was vegetarian, oral iron replacement therapy was commenced without further investigation. On follow-up 6 months later, her iron stores were normal (ferritin, 36 µg/L), but the hair shedding had continued. On examination, there was a positive hair pull test from both the vertex of the scalp and the occipital scalp. There was mild bitemporal recession, but no widening of the central part, and she appeared to have a full, thick head of hair (Fig. 1). Additional investigations at that time revealed normal thyroid function and negative antinuclear antibody (ANA) and syphilis serology. She was on no medication other than Neo-Mercazole. Serum testosterone, dihydroepiandosterone sulphate (DHEAS) and sex hormone binding globulin (SHBG) were normal. Two 4-mm punch biopsies were taken from the vertex of the scalp; one was sectioned horizontally and the other vertically. The vertical section was unremarkable. On the horizontal section, there were 32 hair follicles in total, 30 of which were terminal hairs and two of which were vellus hairs. One hair was in telogen. The ratio of terminal to vellus hairs was 15 : 1. Figure 1. Initial presentation A diagnosis of chronic telogen effluvium was made. The condition was explained to the patient and she was reassured that chronic telogen effluvium is not a progressive condition and does not lead to baldness. No treatment was recommended. At follow-up 12 months later, the hair loss had obviously progressed and the patient was assessed as having Ludwig Stage 1 androgenetic alopecia with widening of the central part (Fig. 2). Repeat blood tests showed normal iron studies, thyroid function, and hormone parameters. Three 4-mm punch biopsies were taken from the vertex of the scalp and all were sectioned horizontally. The terminal to vellus hair ratios were 1 : 1, 2.6 : 1, and 1.9 : 1. A diagnosis of androgenetic alopecia was made and she was commenced on oral spironolactone, 200 mg/day. Figure 2. Presentation after 12 months [source] Hereditary palmoplantar keratoderma (four cases in three generations)INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2001Virendra N. Sehgal MD A 39-year-old man reported with progressive thickening of the skin of the hands and feet and an inability to flex his hand. It was largely asymptomatic; however, brisk walking caused excessive sweating, pain, and widening of the fissures on the soles of the feet. He was unable to walk barefooted. According to his mother, the first episode presented with blistering at 7 days of age. Ever since, the condition has steadily worsened to acquire the current status. He was married at the age of 18 years, and had a stillborn child 18 months afterwards. Presently, he has three children, two girls aged 14 and 12 years and a son aged 10 years. Both the daughters are similarly affected. While cataloguing the details of the pattern of inheritance, the mother of the index case was also found to be affected (Fig. 1). The natural history of the disease was identical. Figure 1. Palmoplantar keratoderma: pattern of inheritance; black indicates affected individuals Examination of the palms was marked by pronounced thickening of the skin resulting in the masking of palmar creases. The thickening was well demarcated and its margins were prominent and surrounded by an erythematous halo. The color of the skin was yellow and waxy (Fig. 2a). Contractures were present on all the fingers; nevertheless, the deformity of the middle and distal interphalangeal joints of the little finger was prominent. The soles of the feet had a similar morphology. In addition, marked fissuring was obvious (Fig. 2b). His daughters had an identical affliction of the palms and soles. The texture and morphology of the nails were normal. Light microscopy performed on scrapings from the fissures, mounted on 10% potassium hydroxide, revealed mycelia (hyphae) and spores. Figure 2. Well-demarcated hyperkeratosis depicting the yellow, waxy color of the palms, with masking of creases (a). Marked fissuring on the soles was prominent (b) Hematoxylin and eosin-stained microsections from the palms and soles showed exquisite changes in the epidermis characterized by considerable uniform orthohyperkeratosis. Hypergranulosis and acanthosis were other associated changes. In addition, perinuclear vacuolization and keratohyalin granules of varying sizes and shapes were located at the periphery of the cells. A sparse mononuclear infiltrate was located at the dermo-epidermal junction. Hyphae and spores of fungi were also identified in the stratum corneum (Fig. 3). Figure 3. Orthohyperkeratosis, hypergranulosis, and acanthosis. Perinuclear vacuolization and keratohyalin granules at the periphery of the cells; a sparse mononuclear infiltrate was also present (hematoxylin and eosin, ×,40 (a), ×,400 (b)) Itraconazole, 400 mg/day in two equally divided doses, was administered with major meals for 7 days. In addition, high doses of vitamin A (100,000 IU) were given daily for 2 weeks, supplemented by 12% salicylic acid (Salicylix SF12) ointment for daytime application and an ointment containing 6% coal tar and 3% salicylic acid (Salytar) for night-time application. This treatment is useful in recalcitrant cases. [source] Nuclear aggregates of polyaminesIUBMB LIFE, Issue 2 2006Luciano D'Agostino Abstract Nuclear aggregates of polyamines (NAPs) are cyclic supramolecular compounds made of polyamines and phosphate groups. Three different aggregates, s-NAP, m-NAP and l-NAP, with a molecular weight of 1035, 5175 and 9552 Da, respectively, are described. These molecules interact with genomic DNA. In consequence of this interaction, NAPs not only protect DNA from nucleases with extraordinarily greater efficiency than single polyamines (spermine, spermidine and putrescine), but also induce noticeable changes in DNA condensation status, as shown by temperature-dependent modifications of DNA electrophoretic properties. The biochemical characterization of these compounds has allowed the definition of a structural model for each NAP. According to this model, five s-NAPs assemble together to form a m-NAP unit. We hypothesize that the complexation of s-NAP into m-NAP favours the transition to Z-DNA through the progressive widening of DNA strands and the exposure of bases. We propose that NAPs, by wrapping the DNA helixes, form supramolecular tunnel-like structures that confer efficient protection without affecting DNA elasticity. iubmb Life, 58: 75-82, 2006 [source] Floristic turnover in Iceland from 15 to 6 Ma , extracting biogeographical signals from fossil floral assemblagesJOURNAL OF BIOGEOGRAPHY, Issue 9 2007Friđgeir Grímsson Abstract Aim, This study aims to document the floristic changes that occurred in Iceland between 15 and 6 Ma and to establish the dispersal mechanisms for the plant taxa encountered. Using changing patterns of dispersal, two factors controlling floristic changes are tested. Possible factors are (1) climate change, and (2) the changing biogeography of Iceland over the time interval studied; that is, the presence or absence of a Miocene North Atlantic Land Bridge. Location, The North Atlantic. Methods, Species lists of fossil plants from Iceland in the time period 15 to 6 Ma were compiled using published data and new data. Closest living analogues were used to establish dispersal properties for the fossil taxa. Dispersal mechanisms of fossil plants were then used to reconstruct how Iceland was colonized during various periods. Results, Miocene floras of Iceland (15,6 Ma) show relatively high floristic turnover from the oldest floras towards the youngest; and few taxa from the oldest floras persist in the younger floras. The frequencies of the various dispersal mechanisms seen in the 15-Ma floras are quite different from those recorded in the 6-Ma floras, and there is a gradual change in the prevailing mode of dispersal from short-distance anemochory and dyschory to long-distance anemochory. Two mechanisms can be used to explain changing floral composition: (1) climate change, and (2) the interaction between the dispersal mechanisms of plants and the increasing isolation of proto-Iceland during the Miocene. Main conclusions, Dispersal mechanisms can be used to extract palaeogeographic signals from fossil floras. The composition of floras and dispersal mechanisms indicate that Iceland was connected both to Greenland and to Europe in the early Middle Miocene, allowing transcontinental migration. The change in prevalence of dispersal modes from 15 to 6 Ma appears to reflect the break-up of a land bridge and the increasing isolation of Iceland after 12 Ma. Concurrent gradual cooling and isolation caused changes in species composition. Specifically, the widening of the North Atlantic Ocean prevented taxa with limited dispersal capability from colonizing Iceland, while climate cooling led to the extinction of thermophilous taxa. [source] Mandibles and molars of the wood mouse, Apodemus sylvaticus (L.): integrated latitudinal pattern and mosaic insular evolutionJOURNAL OF BIOGEOGRAPHY, Issue 2 2007Sabrina Renaud Abstract Aim, The distinct nature of island populations has traditionally been attributed either to adaptation to particular insular conditions or to random genetic effects. In order to assess the relative importance of these two disparate processes, insular effects were addressed in the European wood mouse, Apodemus sylvaticus (Linnaeus, 1758). Location, Wood mice from 33 localities on both mainland and various Atlantic and western Mediterranean islands were considered. This sampling covers only part of the latitudinal range of A. sylvaticus but included the two main genetic clades identified by previous studies. Islands encompass a range of geographical conditions (e.g. small islands fringing the continent through large and isolated ones). Methods, The insular syndrome primarily invokes variations in body size, but ecological factors such as release from competition, niche widening and food availability should also influence other characters related to diet. In the present study, the morphology of the wood mice was quantified based on two characters involved in feeding: the size and shape of the mandibles and first upper molars. The size of the mandible is also a proxy for the body size of the animal. Patterns of morphological differentiation of both features were estimated using two-dimensional outline analysis based on Fourier methods. Results, Significant differences between mainland and island populations were observed in most cases for both the mandibles and molars. However, molars and mandibles displayed divergent patterns. Mandible shape diverged mostly on islands of intermediate remoteness and competition levels, whereas molars exhibited the greatest shape differentiation on small islands, such as Port-Cros and Porquerolles. A mosaic pattern was also displayed for size. Body and mandible size increased on Ibiza, but molar size remained similar to mainland populations. Mosaic patterns were, however, not apparent in the mainland populations. Congruent latitudinal variations were evident for the size and shape of both mandibles and molars. Main conclusions, Mosaic evolution appears to characterize insular divergence. The molar seems to be more prone to change with reduced population size on small islands, whereas the mandible could be more sensitive to peculiar environmental conditions on large and remote islands. [source] An exploratory study of the perceptions and experiences of further education amongst the young long-term unemployedJOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 5 2002Bruce Bolam Abstract The aim of this study was to explore, in depth, the perceptions and experiences of Further Education (FE) amongst the young long-term unemployed. Semi-structured interviews were conducted with 16 long-term unemployed youths of 18,25 years of age divided into three groups: those with no experience of FE; those having recently dropped out of FE; and those currently studying in FE. Grounded theoretical analysis highlighted the importance of both responses to and institutional aspects of unemployment. The impact of unemployment, poor previous educational experience and perceived irrelevance of FE are key barriers to learning. Those that enter FE may drop out as a result of both material and psychosocial factors. Those that stay on commonly emphasize both social support and personal agency in decision-making alongside positive evaluations of FE. In conclusion, limitations of the findings, policy and practical recommendations for successful widening of participation in FE amongst this group are considered. Copyright © 2002 John Wiley & Sons, Ltd. [source] Molecular architecture of myelinated peripheral nerves is supported by calorie restriction with agingAGING CELL, Issue 2 2009Sunitha Rangaraju Summary Peripheral nerves from aged animals exhibit features of degeneration, including marked fiber loss, morphological irregularities in myelinated axons and notable reduction in the expression of myelin proteins. To investigate how protein homeostatic mechanisms change with age within the peripheral nervous system, we isolated Schwann cells from the sciatic nerves of young and old rats. The responsiveness of cells from aged nerves to stress stimuli is weakened, which in part may account for the observed age-associated alterations in glial and axonal proteins in vivo. Although calorie restriction is known to slow the aging process in the central nervous system, its influence on peripheral nerves has not been investigated in detail. To determine if dietary restriction is beneficial for peripheral nerve health and glial function, we studied sciatic nerves from rats of four distinct ages (8, 18, 29 and 38 months) kept on an ad libitum (AL) or a 40% calorie restricted diet. Age-associated reduction in the expression of the major myelin proteins and widening of the nodes of Ranvier are attenuated by the dietary intervention, which is paralleled with the maintenance of a differentiated Schwann cell phenotype. The improvements in nerve architecture with diet restriction, in part, are underlined by sustained expression of protein chaperones and markers of the autophagy,lysosomal pathway. Together, the in vitro and in vivo results suggest that there might be an age-limit by which dietary intervention needs to be initiated to elicit a beneficial response on peripheral nerve health. [source] Beef safety shocks and dynamics of vertical price adjustment: The case of BSE discovery in the U.S. beef sectorAGRIBUSINESS : AN INTERNATIONAL JOURNAL, Issue 3 2007Sayed H. Saghaian This article addresses the dynamic impact of the 2003 Bovine Spongiform Encephalopathy discovery on the U.S. beef sector. Time series analysis and historical decomposition with weekly feedlot, wholesale, and retail beef price series is used to address the dynamics of price adjustment and causality along the U.S. beef marketing channel. The results show price transmission is bidirectional, determined through interaction between the different stages, and price adjustment is asymmetric with respect to both speed and magnitude. The results reveal a differential impact of the exogenous shock on producers and retailers, which leads to widening of price margins and points to imperfect price transmission, specifically at the retail level, with consequences for the efficiency and equity of the marketing channel. [EconLit citations: Q11, Q13]. © 2007 Wiley Periodicals, Inc. Agribusiness 23: 333,348, 2007. [source] Functional genital morphology of armored spiders (Arachnida: Araneae: Tetrablemmidae)JOURNAL OF MORPHOLOGY, Issue 9 2008Matthias BurgerArticle first published online: 18 JUN 200 Abstract This study describes the female genitalia of the tetrablemmid spiders Brignoliella acuminata, Monoblemma muchmorei, Caraimatta sbordonii, Tetrablemma magister, and Ablemma unicornis by means of serial semi-thin sections and scanning electron microscopy and compares the results with previous findings on Indicoblemma lannaianum. Furthermore, the male palps and chelicerae are briefly described. The general vulval organization of females is complex and shows similarities in all of the investigated species. The copulatory orifice is situated near the posterior margin of the pulmonary plate. The opening of the uterus externus lies between the pulmonary and the postgenital plate. Paired copulatory ducts lead to sac-like receptacula. Except for A. unicornis, the male emboli of all investigated species are elongated and thread-like. However, they are too short to reach the receptacula. Hence, the spermatozoa have to be deposited inside the copulatory ducts. The same situation was also found in I. lannaianum. Females of this species store sperm encapsulated in secretory balls in their receptacula. The secretion is produced by glands adjoining the receptacula. The presence of paired fertilization ducts and spermatozoa in the uterus internus suggested that fertilization takes place internally in I. lannaianum. Secretory balls in the receptacula are found in all of the investigated species in this study, showing that sperm are stored in the same way. The place of fertilization may also be identical since dark particles, presumably spermatozoa, are located in the uterus internus of all investigated species except for T. magister. However, fertilization ducts are only found in B. acuminata and M. muchmorei. A sclerotized central process with attached muscles is present in A. unicornis, M. muchmorei, C. sbordonii and T. magister. Only in A. unicornis does the central process show an internal lumen and hold spermatozoa. In the other species, it could be used to lock the uterus during copulation in order to prevent sperm from getting into it as suggested for certain oonopid species. The uterus externus of all investigated species shows a sclerotized dorsal fold with attached muscles, previously described as "inner vulval plate." Contractions of the muscles lead to a widening of the dorsal fold, thus creating enough space for the large oocytes to pass the narrow uterus externus. The males of all investigated species have apophyses on their chelicerae. At least in B. acuminata and A. unicornis, where females have paired grooves on the preanal plate, these apophyses allow males to grasp the female during copulation as described for I. lannaianum. © 2008 Wiley-Liss, Inc. [source] Odontocete suction feeding: Experimental analysis of water flow and head shapeJOURNAL OF MORPHOLOGY, Issue 12 2006Alexander J. WerthArticle first published online: 13 NOV 200 Abstract The role of cranial morphology in the generation of intraoral and oropharyngeal suction pressures in odontocetes was investigated by manipulating the jaw and hyolingual apparatus of submerged heads of three species presenting varied shapes. Hyoid and gular muscles were manually employed to depress and retract the tongue. Pressures were recorded at three locations in the oral cavity, as gape and site, speed, and force of pull were varied. A biomechanical model was also developed to evaluate pressure data. The species with the shortest, bluntest head and smallest mouth opening generated greater negative pressures. Suction generation diminished sharply as gape increased. Greatest negative pressures attained were around ,45 mmHg (,6,000 Pa), a magnitude deemed suitable for capture of small live prey. Odontocetes utilizing this bidirectional flow system should profit by evolution of a rounder mouth opening through progressive shortening and widening of the rostrum and jaws, a trend evident in cranial measurements from fossil and recent odontocetes. Blunt heads correlate with anatomical, ecological, and behavioral traits associated with suction feeding. Small-gape suction (with minimally opened jaws) could be used by odontocetes of all head and oral shapes to draw prey sufficiently close to the mouth for suction ingestion or grasping via dentition. Principal limitations of the experimental and mathematical simulations include assumption of a stationary odontocete with static (open or closed) jaws and potential scaling issues with differently sized heads and gapes. J. Morphol., 2006. © 2006 Wiley-Liss, Inc. [source] Larynx morphology and sound production in three species of TestudinidaeJOURNAL OF MORPHOLOGY, Issue 2 2004Roberto Sacchi Abstract Although the ability to vocalize is widespread among tortoises, the mechanisms of sound production in chelonians remain undescribed. In this study, we analyze the morphology and histology of the larynx of three species of Testudinidae (Testudo hermanni, T. graeca, and T. marginata) in order to ascertain the presence of vibrating acoustic structure, and based on our findings we propose a general model for phonation in tortoises. The structure of the larynx of the three tortoises analyzed is simple: three cartilages (the cricoid and two arytenoids) form the skeleton of the larynx, while two pairs of muscles (the dilators and constrictors) control the widening and closing of the glottis. The larynx is supported in the oral cavity by the hyoid cartilage, which in tortoises assumes the same functions of the thyroid cartilage of mammals. Two bands of elastic fibers are inserted in the lateral walls of the larynx just upstream of the glottis, and can be stretched away from the hyoid by the movements of the arytenoids. Their position and structure suggest that these bands are capable of vibrating during exhalation, and therefore may be considered vocal cords. The cricoid of T. marginata and T. graeca hold two diverticula, not previously reported, which might function as a low-frequency resonating chamber, improving the harmonic structure of tortoise calls. The structure of the larynx is compared with that of other vertebrates and the relationships between morphology and phonation are discussed. This is the first detailed description of anatomical structures possibly devoted to vocalization in chelonians. J. Morphol. 261:175,183, 2004. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||