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Notes: A conventional zero-dimensional (uniform plasma parameters with no spatial variations) fluid model will provide a good match with an experimental electron cyclotron resonance ion source (ECRIS) charge-state distribution (CSD) if provided with a judicious set of user inputs. However, this arbitrarily chosen set of inputs is not necessarily unique. To be truly predictive, an ECRIS model should rely on experimental parameters as inputs. A multi-species model for an ECRIS plasma using experimental parameters as inputs is under development. The model eliminates electron temperature as a user input by employing a 2 V(v,θ) Fokker–Planck code with an ECR heating term to calculate the non-Maxwellian anisotropic electron distribution function. Further arbitrary user inputs are eliminated in favor of controlled parameters by bounce averaging the Fokker–Planck coefficients for a one-dimensional (1D)/2 V axial model. The neutral gas modeling has been extended to 1D using axially coupled particle balance equations. The improved model is able to reproduce experimental Faraday cup (CSDA) from the Argonne National Laboratory's ECR-II. Further elimination of arbitrary inputs is expected when the ion model is extended to 1D. © 2000 American Institute of Physics.

Notes: The injection of Ar into the region of the DIII-D divertor is a promising technique for energy dissipation (through radiation and collisions) and consequently for reduction of the heat load on the plates. An important problem related to this technique, is the inherent poisoning of the core plasma by migrating Ar. The Ar core contamination seems also to improve the thermal transport in an advanced operating mode of the tokamak. It is therefore of great importance to measure the evolution of the impurity concentration profile within the core plasma. This goal could be achieved by using the Ross filter method in conjunction with the existing x-ray diagnostics on DIII-D. A basic Ross filter system consists of two identical detectors placed behind two different x-ray absorbing foils looking at the same plasma volume. The foils are made of different elements or compounds with adjacent or nearly adjacent atomic numbers. Their accurate thickness causes the x-ray transmission curves of the two foils to be effectively identical over the entire energy range except within the narrow region between their absorption edges. Since the transmission characteristics of the foils above and below their absorption edges are the same, any difference in the two detected signals is proportional to the total x-ray power of the emission spectrum between these two edge energies. An x-ray Ross filter with its energy pass band centered on the Ar XVII Kα line at 3.14 keV has been designed. This allows for the discrimination of the Ar Kα line only, regardless of Ar ionization state, against any background radiation with energies outside the energy pass band. The Ross filter was installed in front of two of the fan shaped poloidal x-ray arrays on DIII-D. The first measurements showed very good discrimination against Ne, another injected impurity. Emissivity profile evolution of the Kα lines and Ar enhanced continuum within the energy pass band of the Ross filter can be determined from the x-ray brightness signals by inverting techniques and by using the Te, ne, and Ar16+ profiles as measured by other diagnostics. The transport code MIST1 can be used to calculate both the emissivity profiles of the Kα of all the ions and their concentration profiles when the measured Te, and ne are used as input. The Ar16+ profiles as measured by charge exchange spectroscopy can be used as a constraint for the MIST code to accurately calculate the Ar18+ profile and thus unfold all the Ar ions Kα emissivity profiles. From these one can determine the Ar concentration profile evolution and the particle diffusion coefficient. In conclusion, using the Ross filter method with the existing x-ray imaging systems results in a powerful and cost-effective diagnostic for impurity transport studies. © 2001 American Institute of Physics.

Notes: 1 In the present investigation we examined the regulation of calmodulin (CaM)- and protein kinase C (PKC)-dependent pathways by cytosolic Ca2+ in the contraction of cat lower oesophageal sphincter (LES). 2 Force developed in response to increasing doses of acetylcholine (ACh) was directly related to the increase of the [Ca2+]i measured by fura-2. Thapsigargin, which depletes Ca2+ stores, reduced the contraction and the [Ca2+]i. In addition, contraction in response to maximal ACh was reduced by the CaM inhibitor CGS9343B but not by the PKC inhibitor chelerythrine. The contraction in response to submaximal ACh was reduced by chelerythrine but not by CGS9343B. 3 In permeabilized cells, the contraction in response to low Ca2+ (0.54 μm) was also reduced by CGS9343B. 4 The response to high Ca2+ (1.0 μm) was reduced by CGS9343B. ACh also inhibited PKC activation induced by diacylglycerol, which activation is inhibited by the N-myristoylated peptide inhibitor derived from pseudosubstrate sequences of PKCαβγ (myr-PKC-αβγ), but not of myr-PKC-α. 5 These data are consistent with the view that activated CaM-dependent pathways inhibit PKC-dependent pathways, this switch mechanism might be regulated by Ca2+ in the LES.

Notes: Neonatal lupus erythematosus (NLE) occurs in neonates of mothers who, in almost all cases, have auto-antibodies to the SSA/Ro associated proteins, but who may have no clinical disease. However, only a small percentage of mothers with SSA/Ro antibodies have affected babies, predisposing factors specific to the foetus or neonate (i.e. HLA pattern) and/or fetal maternal interactions have been proposed to be important. We present a mother with a family history of autoimmune disease, but without clinical disease, whose baby developed cutaneous NLE. Autoantibody determinations as well as the HLA-DR/DQ were performed in the mother and baby. Factors other than the HLA-DR/DQ status of the mother appear to be important in determining whether or not the neonate will develop NLE. Auto-antibodies to endogenous antigens common to the mother, transiently expressed developmental antigens, and the isotype specificity of transferred antibodies may be important in determining disease in the baby.

Notes: Summary To determine the best molecular method for diagnosing leprosy, two sets of Mycobacterium leprae-specific primers were compared. Fresh biopsies and slit skin smear samples were obtained from 67 leprosy patients and examined by touchdown (TD) PCR using primers amplifying either a 129-bp fragment of the RLEP repetitive sequence or a 360-bp fragment of the 18-kDa protein gene of M. leprae. Seventeen of 30 (56.7%) biopsy specimens and four of 37 (10.8%) slit skin smear specimens were positive using the primer for the 18-kDa protein gene, whereas 24 of 30 (80%) biopsy and 27 of 37 (73%) slit skin smear samples showed detectable PCR products in the RLEP repetitive sequence. Twenty-one of 31 cases (67.7%) with a bacterial index of zero were PCR positive for the primer RLEP repetitive sequence. These results demonstrate that detection of M. leprae using PCR with primers to a RLEP sequence is more sensitive and specific than PCR with the 18-kDa protein gene primers and also slit smears with acid fast staining. PCR of RLEP repetitive sequences is therefore a useful means of detecting M. leprae DNA even when it is present at very low levels.

Notes: Background  Human skin colour shows variations throughout life, and many extrinsic and intrinsic factors influence melanogenesis. Facultative pigmentation of sun-exposed skin has been suggested to reflect cumulative lifetime ultraviolet (UV) exposure in caucasians. However, pigmentary changes due to various regulatory factors may be different in dark-skinned peoples. Objectives  To observe the variations in skin colour due to ageing, gender differences and seasonal changes in Koreans with skin type IV or V. Methods  Skin pigmentation was measured at five body sites (buttock, glabella, the V of the neck area, inner arm and dorsal forearm) using skin reflectance spectroscopy in 497 subjects (age range 0–87 years) in winter and 311 subjects (age range 0–84 years) in summer. Among these subjects, 110 were assessed in both seasons. Three independent measurements at each site were done and the average value was used as the pigmentation level. Results  Constitutive pigmentation of the buttock was highest in the first decade of life. It then decreased during the second decade and this decreased level was maintained after the third decade. In contrast to caucasians, facultative pigmentation and sun exposure index did not increase with ageing. Gender differences were significant at all body sites after the first decade. Seasonal changes were apparent in dorsal forearm pigmentation. Little difference was seen in forehead pigmentation between summer and winter. Conclusions  Basal melanogenic regulation might not be different between Asians and caucasians. However, the sun exposure index may not represent lifelong cumulative UV exposure in Koreans. Age-, gender- and season-related characteristics of skin pigmentation in Koreans imply that genetically determined basal skin colour plays an important part in characterizing later responsiveness to UV radiation and sex hormones. Understanding differences between races will be helpful in studying the regulatory mechanisms of melanogenesis.

Notes: Room temperature deposition of tantalum oxide films on metallized silicon substrates was investigated by reactive pulsed magnetron sputtering of Ta in an Ar/O2 ambient. The dielectric constant of the tantalum oxide ranged from 19 to 31 depending on the oxygen percentage [P(%)=PO2/(PO2+PAr)] used during sputtering. The leakage current density was less than 10 nA/cm2 at 0.5 MV/cm electric field and the dielectric breakdown field was greater than 3.8 MV/cm for P=60%. A charge storage as high as 3.3 μF/cm2 was achieved for 70-Å-thick film. Pulse frequency variation (from 20 to 200 kHz) did not give a significant effect in the electrical properties (dielectric constant or leakage current density) of the Ta2O5 films. © 2000 American Institute of Physics.

Notes: This study presents a new approach that can stabilize effectively l-ascorbic acid in water-in-oil-in-water (w/o/w) double emulsions. Basically, the behavior of l-ascorbic acid in the aqueous phase was observed, considering its molecular deformation. Then, it was found that the stability determined in the aqueous phase by high-performance liquid chromatography (HPLC) showed that the collapse of ionization of l-ascorbic acid played a crucial role in protecting the molecular deformation. Then, the stable aqueous system was incorporated into the internal aqueous phase of the double emulsions. From the PLC analysis, it was observed that the l-ascorbic acid in an appropriate system showed high molecular stability for a long time. Moreover, in the measurement of in vitro skin permeation, the l-ascorbic acid stabilized in this study showed considerable skin permeation ability, indicating its potential applicability in pharmaceutics and cosmetics.

Notes: This study tested the effects of culture and self-construals (i.e., independence and interdependence) on predispositions toward verbal communication. For the purpose of this study, we focused on two main areas of verbal communication predispositions: (a) communication apprehension and (b) argumentativeness. In our path model, we expected that culture-level individualism increases one's construal of self as independent, which, in turn, leads to a higher degree of argumentativeness and a lower level of communication apprehension. We also expected that culture-level individualism decreases one's construal of self as interdependent, which, in turn, leads to a lower degree of argumentativeness and a higher level of communication apprehension. Data to test the model were drawn from undergraduates (N=539) studying in Korea, Hawaii, and mainland U.S. The data were partially consistent with the theoretical predictions made. The implications of the results for theory and practice are discussed.