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The differential elastic-scattering cross sections and the total reaction cross sections for the interaction of K + mesons with 12C and 40Ca nuclei at beam momenta of 0.635, 0.715, and 0.8 GeV/c are calculated. The microscopic optical potential derived in the high-energy approximation is used in these calculations. It is determined by the amplitude for kaon-nucleon scattering and the density distribution of pointlike nucleons of the target nucleus. In the high-energy approximation, the Klein-Gordon-Fock equation reduces to the form of the Schrodinger equation. It is shown that small distinctions between the reduction methods do not lead to significant changes in differential elastic-scattering cross sections, but the effects of relativization as such are quite large. Good agreement with experimental data on elastic K + A scattering is attained. The total reaction cross sections can be described upon adding, to the volume potential, a term that takes the form of its derivative and which has a maximum at the periphery, its contribution being fitted to experimental data.

Excitation of low-lying nuclear collective states upon scattering of heavy ions with energies of several tens of MeV/nucleon has been studied. The interaction potential leading to excitation is chosen in the form of a derivative of the microscopic (or semimicroscopic) nucleus-nucleus double-folding optical potential. Elastic and inelastic scattering cross sections have been calculated within the high-energy approximation; the inelastic scattering amplitude was obtained in the first order in the deformation parameter. The cross sections are compared with the experimental data on scattering of 17O from a series of nuclei with excitation of the 2+ level.

Dibarium silicate, Ba2SiO4, was hydrated in two ways: in paste form at 25° using a water/solid weight ratio of 0.7:1, and in a polyethylene bottle rotated on a wheel at 5°, 25° and 50°, using a water/solid weight ratio of 9.0:1. When Ba2SiO4 is hydrated in paste form, the stoicheiometry of the reaction at 25° is the same as in bottle-hydration at 50°: 2BaO.SiO2+2.2H2O = 1.2BaO.SiO2.1.4H2O+0.8Ba(OH)2. The stoicheiometry of bottle-hydration at 5° and 25° is represented by the equation: 2BaO.SiO2+2.2H2O = BaO.SiO.1.2H2O+Ba(OH)2. Barium silicate hydrate, 1.2BaO.SiO2.1.4H2O, is well crystallised and has a specific surface area of ˜ 3m2/g. The crystals are plate-like and have a tendency to form clusters. The low-baria hydrate, BaO.SiO2.1.2H2O, is poorly crystallised and consists of thin platelets. It has a specific surface area of ˜ 35m2/g. The thermal dehydration of fully hydrated barium silicate and of the barium silicate hydrates was investigated by thermogravimetric and differential thermal analysis techniques. The similarities and differences between the barium silicate hydrates obtained in the hydration of barium silicate and the calcium silicate hydrates obtained in the hydration of β-dicalcium silicate and Ca3SiO5 are discussed. A mechanism of hydration of barium silicate is proposed which involves solution, precipitation and crystallisation steps.

THE EFFECT OF VARIOUS CURING CONDITIONS ON THE AMOUNT OF WATER HELD BY PASTES WITH LOW WATER/CEMENT RATIOS WAS INVESTIGATED. IT WAS CONCLUDED FROM THE RESULTS THAT FACTORS SIGNIFICANTLY INFLUENCING THE TOTAL WATER CONTENT OF A CEMENT PASTE MADE WITH ORDINARY PORTLAND CEMENT AND CURED AT ROOM TEMPERATURE ARE: WATER/CEMENT RATIO, CURING MEDIUM, CURING PERIOD AND CURING HISTORY. /AUTHOR/

MEASUREMENTS OF CHEMICALLY COMBINED WATER CONTENTS WERE MADE ON PORTLAND CEMENT PASTES MADE WITH WATER/CEMENT RATIOS OF 0.20 TO 0.30 BY WEIGHT. IN ADDITION TO THE FACTORS INVOLVING WATER/CEMENT RATIO, CURING MEDIUM, CURING HISTORY AND CURING PERIOD, THE DEGREE OF HYDRATION OF CEMENT PASTES CURED AT ROOM TEMPERATURE WAS SIGNIFICANTLY INFLUENCED BY THE AVAILABILITY OF ADEQUATE WATER SUPPLY DURING THE FIRST 24 HOURS OF THE CURING PROCESS. /AUTHOR/

The rate of hydration of dibarium silicate (Ba2SiO4) in paste form at room temperature was investigated. The uncombined barium hydroxide produced in the reaction, determined by a modified Franke method, was used as a measure of the extent of hydration. The linear relationship obtained between the uncombined barium hydroxide and the chemically combined water confirms that similar hydration products are formed at all stages of hydration, and either may be used as a measure of the degree of hydration. The rate of hydration of dibarium silicate was found to be lower than that of tricalcium aluminate, but higher than those of alite, tricalcium silicate and β-dicalcium silicate. The effect of water/solid ratio on the rate of hydration was also investigated. Dibarium silicate was completely hydrated after 30 days when it was mixed with a water/solid weight ratio > 0.7:1.

The possibility of observing a bright interior in the nucleus {open_quotes}viewed{close_quotes} by intermediate energy alpha particles (E{sub {alpha}}=172.5 MeV), as a probe for the Ni{sup 58} nucleus, previously predicted by applying only a first-order noneikonal correction and one simple optical model potential was confirmed. The first-, second-, and third-order noneikonal corrections to the Glauber model were incorporated in three arbitrary different nominal optical potentials and the effects of switching (off/on) the Coulomb potential were studied. The role of corrections in the effective potentials and also the results of calculations of the imaginary part of the phase shift functions for the different optical potentials used were discussed. {copyright} {ital 1997} {ital The American Physical Society}

Parent-adolescent shared responsibility for diabetes care is advocated by experts to achieve beneficial diabetes and psychosocial outcomes for adolescents with type 1 diabetes. Parental autonomy support may be a way to facilitate this sharing. In this dyadic study, we examined parental diabetes-specific autonomy support experienced by adolescents with type 1 diabetes and their parents (n = 89 dyads), and its association with their experience of shared diabetes care responsibility.Path analysis was used to test an Actor-Partner Interdependence Model for parental autonomy support effects on shared responsibility. This was a secondary analysis of data from 89 parent-early/mid-adolescent dyads.Actor effects were identified. Parents' and adolescents' perceptions of parental autonomy support were associated with their respective reports of shared diabetes care responsibility. One partner effect was identified. Adolescents' reports of parental autonomy support were associated with parents' reports of shared responsibility. Parents and adolescents held similar views of autonomy support but discrepant views of shared responsibility. Older adolescents perceived less parental autonomy support.Increasing parental autonomy support may facilitate parent-adolescent sharing of diabetes care responsibility. Adolescent and parent perceptions influence each other and need to be considered when working with them to strengthen parental autonomy support.

Emerging adults with diabetes are assuming diabetes care responsibility, graduating from high school and leaving their parental homes. We examined: (1) how diabetes care responsibility changed in relation to time (high school to post high school) and living situation (living independently or not of parents) and (2) the association of diabetes self-efficacy, worry about hypoglycaemia, gender and glycaemic control with these changes in responsibility among emerging adults with type 1 diabetes. During the last 6 months in high school (T1), 113 participants completed diabetes care responsibility (total, daily and non-daily), diabetes self-efficacy and worry about hypoglycaemia scales. Participants again completed the responsibility scales post high school graduation (T2). We used a linear mixed-effects model with diabetes self-efficacy, worry about hypoglycaemia, time since graduation, living situation, gender and glycaemic control as independent variables; and diabetes care responsibility (total, daily and non-daily) as dependent variables. Moderation involving diabetes self-efficacy, worry about hypoglycaemia, gender and glycaemic control was also tested. Diabetes care responsibility increased over time for total (P0.001), daily (P= 0.002) and non-daily (P0.001), but the associations of self-efficacy and gender with diabetes care responsibility were moderated by living situation. Self-efficacy was negatively related to total (P= 0.006), daily (P= 0.010) and non-daily (P= 0.030) responsibility for those not living independently while positively related only to total responsibility (P= 0.028) for those living independently. Being female was positively related to total (P= 0.007) and non-daily (P= 0.001) responsibility for those living independently. Diabetes care responsibility increased from high school to post high school among these emerging adults with diabetes. There is a complex relationship between self-efficacy, gender and responsibility related to living independently of parents for these youth.

Nuclear quark distribution functions, obtained in the framework of the multiquark cluster model, show that the EMC effect can be explained by taking into account the scattering on colourless multiquark configurations in nuclei. The prediction for the behaviour of the nuclear structure function in the kinematical region X>1, which has not been sufficiently studied experimentally, is given. The Drell-Yan cross sections for lepton pair production in proton-platinum at 440 GeVc-1 and pion-tungsten at pion energy 280 GeV interactions were calculated in addition to the prediction of the behaviour of cross-section ratios in different kinematical regions. The predictions show significant nuclear effects in these processes.

Many critics of commercial surrogate motherhood argue that it violates the rights of children. In this paper, I respond to several versions of this objection. The most common version claims that surrogacy involves child-selling. I argue that while proponents of surrogacy have generally failed to provide an adequate response to this objection, it can be overcome. After showing that the two most prominent arguments for the child-selling objection fail, I explain how the commissioning couple can acquire parental rights by paying the surrogate only for her reproductive labor. My explanation appeals to the idea that parental rights are acquired by those who have claims over the reproductive labor that produces the child, not necessarily by those who actually perform the labor. This account clarifies how commercial surrogacy differs from commercial adoption. In the final section of the paper, I consider and reject three further child-based objections to commercial surrogacy: that it establishes a market in children's attributes, that it requires courts to stray from the best interests standard in determining custodial rights, and that it requires the surrogate to neglect her parental responsibilities. Since each of these objections fails, children's rights probably do not pose an obstacle to the acceptability of commercial surrogacy arrangements.

The (semi-)microscopic double-folding nucleus-nucleus optical potentials are suggested for consideration of inelastic scattering with excitation of collective nuclear states by using the adiabatic approach and the elastic scattering amplitude in the high-energy approximation. The analytical expression for inelastic scattering amplitude is obtained keeping the first order terms in the deformation parameter of a potential. Calculations of inelastic cross sections for the $^{17}$O heavy ions scattered on different nuclei at about hundred Mev/nucleon are made, and the acceptable qualitative agreement with the experimental data is obtained without introducing free parameters. The prospect of the method for further applications is discussed., 9 pages, 3 figures, 1 table, submitted to "Partices and Nuclei, Letters"

Three different signals from the intermediate energy range (IE) (coming from kaons, quarks, and α ‐ particles) are presented to account for the new properties of nuclei. First, we fixed the famous discrepancy of the unconventional behavior of the K+ meson interaction with nuclei (e.g. 12C and 40Ca) in the energy region E ⩽ 1 GeV to be in the ranges (6.5 % – 12 %) and (3.7 % – 7 %) respectively. We used Glauber theory corrected with higher‐order noneikonal (NE) corrections and two‐body short range correlations (CO) between target nucleons taking into account their full Fermi motion (F). This phenomenon is interpreted as a possible EMC‐type effect at this soft IE nuclear reactions. Secondly, we found a convinced physical explanation for the large‐angle diffraction pattern of the IE α ‐ particle scattering from nuclei where the results are sensitive to the details of the real part of the nominal optical potential. We have showed, using also higher‐order NE corrections of Wallace, that the simple picture of t...

Several arguments suggest that dopamine (DA) plays a role in the physiopathology of migraine. Conjugated and unconjugated plasma and platelet DA, as well as platelet phenolsulfotransferase M activity (responsible for DA sulfatation) were measured in 30 control subjects, 27 common migraine patients between attacks and 9 migraineurs during an attack. No modification of any of the parameters tested was detected in attack-free periods. During the attack no change of conjugated DA was observed; in contrast, a significant decrease of unconjugated platelet DA and a significant and correlated increase of plasma unconjugated DA were demonstrated. This corresponds to a release of unconjugated DA by the very dense bodies in platelets of migraine patients during the attack.