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Linear Distribution (linear + distribution)
Selected AbstractsFinite element analysis of advanced multilayer capacitorsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 3 2003L. Vu-Quoc We establish a systematic methodology to design and analyse electromagnetic components such as advanced multilayer ceramic capacitors (MLCCs) using the finite element (FE) method. We employ a coupled formulation to compute the interaction between the electric and magnetic fields. Unlike a linear distribution of current assumed in the circuit model, an accurate electrostatic solution to model the entire advanced MLCCs (4 × 4 × 27 = 432 cells) is presented. The FE solution is used to compute the lumped parameters for a range of frequencies. These lumped parameters are then used to compute the parasitic elements of the MLCCs. We introduce two algorithms to efficiently analyse the behaviour of a capacitor with changing frequency. The lower frequency (much below the self-resonant frequency of the capacitor) algorithm separates the effect of the electric and magnetic fields and reduces the computational effort required to solve the FE problem, whereas, the high-frequency algorithm couples the effect between the electric and the magnetic fields. We use these algorithms in conjunction with a new multiple scale technique to effectively determine the small values of R, L and C in MLCCs. The formulation, the implementation, and the numerical results demonstrate the efficacy of the present FE formulation and establish a systematic methodology to design and analyse advanced electromagnetic components. Copyright © 2003 John Wiley & Sons, Ltd. [source] Linear-agminated juvenile xanthogranulomasINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2008Despoina Kiorpelidou MD An 8-month-old girl presented with an asymptomatic skin lesion on the right popliteal fossa, which had been present for approximately 6 months. The child had a past medical history of a urinary tract infection at the age of 1 month and had been on daily cotrimoxazole since. There was no history of trauma to the site. Examination revealed a solitary, well-demarcated, plaque-like lesion on the right popliteal fossa, with multiple agminated papules in an almost linear distribution (Fig. 1a). The lesion did not follow Blaschko's lines, but was vertical to them. The plaque was slightly indurated, measuring approximately 4 × 1.5 cm, fixed to the overlying skin but movable over the deeper tissue. The papules were yellowish in color and firm to palpation, showing a positive Darier's sign (Fig. 1b,c). There was no regional adenopathy and no other skin lesions were observed. The physical examination and laboratory investigations were otherwise unremarkable. There was no hepatosplenomegaly, and an ocular examination and chest X-ray were normal. Figure 1. Juvenile xanthogranuloma: agminated nodulopapular lesions on the right popliteal fossa (a) showing positive Darier's sign (b and c; arrows) ,A biopsy from the lesion (Fig. 2a) revealed a dermal infiltrate of histiocytes, some of which were foamy, and admixed Touton-type giant cells, lymphocytes, eosinophils, and mast cells. By immunohistochemistry, the predominant cell population was CD68 (KP-1, MIB-1, and PG-M1, all pursued from Dako) positive, but S-100 protein and CD1a negative (Fig. 2b,e). By Giemsa stain, scattered mast cells (< 5% of the total cell number) were detectable within the lesion. The morphology and immunohistochemistry of the lesion were diagnostic for juvenile xanthogranuloma. Eight months later, the lesion was still present but slightly elongated, proportional to the child's growth, and hyperpigmented. Figure 2. Juvenile xanthogranuloma: histomorphology of skin lesion showing a cell-rich histiocytic dermal infiltrate (a) with immunohistochemical characteristics (b,e) of non-Langerhans dendritic cells (a, hematoxylin and eosin; b, anti-S-100 protein; c, anti-CD-1a; d, e, anti-CD68 monocytic markers MIB-1 and KP-1, respectively; a,e, initial magnification ×40) [source] A Japanese case of Kindler syndromeINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2000Yasushi Suga MD A 25-year-old Japanese woman presented with contracture of the fingers and toes, and difficulty in opening her mouth. Her grandparents are first cousins, but none of the other members of the family are affected. Bulla formation started at birth on areas of the skin that received pressure, and in infancy and early childhood the lesions were limited only to the acral areas. She also had bilateral, incomplete syndactylies involving all web spaces ( Fig. 1a). The formation of blisters ceased after the age of 15 years, but a generalized progressive poikiloderma then appeared with accompanying cutaneous atrophy of the skin of the neck, trunk, and extremities ( Fig. 1b). The patient experienced mild photosensitivity of the face and neck. At age 18 years, surgical removal of the webbing of all her fingers was performed. Oral examination showed atrophy of the buccal mucosa, and an inability to fully open the mouth. The patient also suffered from poor dentition and easily bleeding gums, but had no symptoms of esophageal dysfunction. Figure 1. Clinical manifestations of the patient with Kindler syndrome. (a) Dorsal surface of the patient's hands. Note the marked cutaneous atrophy with a severely wrinkled appearance on the dorsal surface of the hands, as well as the proximal fusion of the fingers. (b) Lower left leg of the patient. Atrophic thinning of the skin and poikiloderma with reticular pigmentation are evident Histology of separate biopsy specimens, taken from the poikilodermatous pretibial and trunk skin, showed classical features of poikiloderma, namely epidermal atrophy with flattening of the rete ridges, vacuolization of basal keratinocytes, pigmentary incontinence, and mild dermal perivascularization ( Fig. 2a). Interestingly, dyskeratotic cells ( Fig. 2b) and eosinophilic rounded bodies (colloid bodies) ( Fig. 2c) were frequently found at the basal keratinocyte layer and in the upper dermis, respectively. Pigment was also present in the upper epidermis. Figure 2. Hematoxylin and eosin staining of a biopsy specimen taken from pretibial skin. (a) Epidermal atrophy with flattening of the rete ridges. Note the dyskeratotic cells (arrowheads) and vacuolar degeneration of the basal layer in the epidermis. Bar = 50 ,m. (b) Higher magnification of dyskeratotic cells (arrowheads). Bar = 10 ,m. (c) Higher magnification of colloid bodies (arrowheads) in the superficial dermis. Bar = 10 ,m To rule out the possibility of a congenital epidermolysis bullosa, ultrastructural and immunofluorescence studies were performed. Ultrastructural studies demonstrated the reduplication of the basal lamina with branching structures within the upper dermis and cleavage between the lamina densa and the cell membrane of the keratinocytes ( Fig. 3a). The numbers of associated anchoring fibrils did not seem to be reduced, and colloid bodies and dyskeratotic cells were detected. Immunofluorescence studies with the antibody against type VII collagen (LH 7 : 2) were subsequently carried out. The results showed extensive broad bands with intermittently discontinuous and reticular staining at the dermo-epidermal junction (DEJ) ( Fig. 3b), whereas a linear distribution is typically seen in healthy tissue (data not shown). Interestingly, direct immunofluorescence studies revealed intracellular accumulation of immunoglobulin G (IgG), IgM, IgA, and C3 in colloid bodies under the basement membrane ( Fig. 3c). Figure 3. Ultrastructural and immunohistochemical findings of the patient with Kindler syndrome. (a) Ultrastructural study of the dermo-epidermal junction. The branching structures of the lamina densa (arrowheads) were frequently seen. The asterisks show the cleavage in the lamina lucida. Bar = 1 ,m. (b) Immunohistochemical studies with the antibody to type VII collagen (LH 7 : 2). An extensive broad band with reticular patterns is evident. Bar = 50 ,m. E, epidermis; D, dermis. (c) Direct immunofluorescence study. Intracytoplasmic deposition of IgM in the basal keratinocytes is evident (arrowheads). Bar = 50 ,m. E, epidermis; D, dermis [source] Expulsion of a geopressured hydrothermal system associated with destructive earthquakes and buried active faults in the Shinanogawa Seismic Belt, JapanISLAND ARC, Issue 2 2004Huilong Xu Abstract The Shinanogawa Seismic Belt in the Northern Fossa Magna, Honshu Island, Japan, extends along the Shinano River, bounding the Eurasian Plate and the Okhotsk Plate. The geopressured hydrothermal system occurs widely in the Northern Fossa Magna region. Many destructive earthquakes are related to the activity of this system in the Shinanogawa Seismic Belt. Expulsion of a geopressured hydrothermal system and rising from depth along an active fault triggers the occurrence of an earthquake and opens the fault as a pathway. Anomalous areas in temperature, electrical conductivity and Cl, concentration of groundwater trend north,east in a linear distribution, and convincingly demonstrate the presence of a buried active fault at the epicentral area of the destructive earthquake in the Shinanogawa Seismic Belt. The distribution of the major axis of the anomalous area in groundwater temperature shows a strong positive relationship with earthquake magnitude, which means that the distribution of this area may indicate the scale of earthquake fault. The linearly anomalous areas in groundwater temperature, resulting from the percolation of a geopressured hydrothermal system, that have no record of previous destructive earthquake are predicted to be areas where destructive earthquakes could occur in the future. Four potential earthquake areas are proposed and discussed in this paper, based on re-examination of active faults and seismicity in the Shinanogawa Seismic Belt. [source] Bilateral Systematized Porokeratotic Eccrine Ostial and Dermal Duct Nevus with Unilateral Breast HypoplasiaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005A. Jayaraman Porokeratotic eccrine ostial and dermal duct nevus (PEODDN) is a rare hamartomatous malformation of the eccrine duct which typically presents at birth or early in life. Multiple punctate pits and verrucous papules and plaques with nonfollicular hyperkeratotic spines are seen over the palms and soles and may extend to the distal extremities. A linear distribution may be present. A wide range of involvement has been reported in the literature, including bilateral systematized involvement. No systemic involvement has been linked to PEODDN to date. Histologic findings are characteristic and include a dilated eccrine acrosyringium with an overlying parakeratotic column or cornoid lamella. There is slight dyskeratosis and loss of the granular layer under the cornoid lamella. Here, we present a case of bilateral systematized PEODDN in an otherwise healthy, 18 year-old Hispanic female. Physical examination is notable for marked hypoplasia of the left breast with overlying verrucous papules and plaques. Multiple punch biopsies were performed and showed findings diagnostic of PEODDN. To our knowledge, this is the most extensive involvement of PEODDN reported in the literature to date and the only case with associated hypoplasia of the breast. [source] Effects of composition distribution on electronic structures of self-assembled InGaN/GaN quantum dotsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 7 2010Wei-Yi Tsai Abstract In this study, we investigate the influences of different composition distributions on the electronic structures of truncated cone-shaped InGaN quantum dots (QDs). A varying parameter, , is defined as , in which w1 and w2 are the top and base diameter of QD, respectively. This factor is set to study the role of similar truncated cones with the same base diameter and height on electronic structures of QD. Three indium composition distributions are considered: ellipsoid, uniform, and linear. The single-band effective-mass equation and six-band k·p theory are used to calculate the transition energies of electrons and holes, respectively. The numerical results reveal that the parameter plays an important role in changing the piezoelectric potential. In addition, an InGaN quantum dot with a linear distribution of indium has the maximum transition energy, whereas one with an ellipsoidal distribution has the minimum value. It is noteworthy that the binding energy greatly decreases as increases for different indium distributions. [source] | ||||||||||