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Background: Based on the vulnerability model, several studies indicate that low self-esteem seems to contribute to depressive symptoms. Aims: The aim of this study was to treat depressive symptoms in a cognitive behavioural group therapy, focusing on the enhancement of self-esteem, and to explore co-variation in depressive symptoms and the level of self-esteem. Method: The Multidimensional Self-esteem Scale (MSWS) and the Beck Depression Inventory (BDI) were administered to 147 psychiatric in-patients with current depressive symptoms due to an affective disorder (major depression, bipolar I, dysthymia). Self-esteem was measured pre-treatment (t0) and post-treatment (t4, after 5 weeks of eight group sessions); the BDI was applied weekly. A linear mixed growth analysis was conducted to estimate the change in depressive symptoms including interactions with self-esteem. Results: Within the 5 weeks of group therapy, depressive symptoms showed a linear decline, which was stronger for patients with higher gains in self-esteem between t0 and t4. Self-esteem at t0 was unrelated to the change in depression but predicted self-esteem at t4. Conclusions: Treating depressive symptoms in a cognitive behavioural group therapy in a naturalistic setting might have a positive effect on the process of recovery. Moreover, depressive symptoms and level of self-esteem seemed to co-vary.
Established in 1911 as a simple owner-operated commercial school in Providence, Rhode Island, the Katharine Gibbs School expanded over the decades to acquire an international reputation for excellence in secretarial training. This essay examines the origin, development, and ultimate demise of the chain, placing it within the context of the expansion of office work and the growth of clerical education. In presenting a secretarial career as an attractive option for women, the school developed a gender-specific message that was very much in keeping with the vocationalism that became a major component of women's education in both public high schools and proprietary institutions. Promoting the career secretary as a desirable career path for women, Gibbs used class and gender-based marketing to separate itself from competitors. Thriving at a time when educated women had few opportunities, the school declined when the feminist upheavals of the 1960s sparked a new ethos of workplace egalitarianism and widening cultural definitions of self-fulfillment for women.
The De tonitruis (or De tonitruis libellus ad Herefridum) attributed to Bede is a short text containing a prologue and four chapters dealing with the meaning of thunder heard (I) in each of the four cardinal directions, (II) in each of the twelve months of the year, (III) on each of the seven days of the week, and (IV) at certain hours of the day and of the night. The text was first published among Bede's works by Noviomagus in Cologne in 1537 and was subsequently reprinted in all editions of the complete works of Bede, including Migne's Patrologia Latina. Charles W. Jones, who was the first to discuss the De tonitruis in detail, convincingly dismissed the attribution to Bede and identified what he thought to be the only extant MS (and also the exemplar used by Noviomagus): Cologne, Erzbischöfliche Diözesan- und Dombibliothek, 102, fols. 49r–52v, copied in Cologne in the first half of the eleventh century.
The long-term efficacy of psychological treatments for binge eating disorder remains largely unknown.
To examine the long-term efficacy of out-patient group cognitive–behavioural therapy (CBT) and group interpersonal psychotherapy (IPT) for binge eating disorder and to analyse predictors of long-term non-response.
Ninety people with binge eating disorder were assessed 4 years after treatment cessation within a randomised trial (trial registration: NCT01208272).
Participants showed substantial long-term recovery, partial remission, clinically significant improvement and significant reductions in associated psychopathology, despite relapse tendencies in single secondary outcomes. Body mass index remained stable. While the IPT group demonstrated an improvement in eating disorder symptoms over the follow-up period, the CBT group reported a worsening of symptoms, but treatments did not differ at any time point.
The results document the long-term efficacy of out-patient CBT and IPT for binge eating disorder. Further research is warranted to elucidate the time course and mechanisms of change of these treatments for binge eating disorder.
For a certain class of first order systems of differential equations several theorems are derived which give sufficient conditions for an appropriate sesquilinear form to be identically zero on suitable spaces of solutions of the system. As a consequence for second order systems limit-point criteria are obtained which include rather general criteria in the case of second order equations. The method used involves sequences of auxiliary functions and is most expedient for the proof of interval limit-point criteria. The theory is also applicable to second order equations with complex coefficients yielding sufficient conditions for the existence of solutions which are not of integrable square.
Quasi-differential expressions with matrix-valued coefficients, which generalize those of Shin and Zettl, are considered with regard to equivalence, adjoints and symmetry. The characterization results imply that in the scalar case the class of quasi-differential expressions considered here coincides with that of Shin and is equivalent to that of Zettl. Furthermore polynomials in quasi-differential expressions are defined as expressions of the same kind and shown to coincide with the usual ones. Finally it is indicated that the known general results for the deficiency indices carry over to quasi-differential expressions.
Optimising a sequence of actions to attain some future goal is the general topic of control theory [26, 9]. It views an agent as an automaton that seeks to maximise expected reward (or minimise cost) over some future time period. Two typical examples that illustrate this are motor control and foraging for food.
As an example of a motor control task, consider a human throwing a spear to kill an animal. Throwing a spear requires the execution of a motor program that is such that at the moment that the hand releases the spear it has the correct speed and direction to hit the desired target. A motor program is a sequence of actions, and this sequence can be assigned a cost that consists generally of two terms: a path cost that specifies the energy consumption to contract the muscles to execute the motor program, and an end cost that specifies whether the spear will kill the animal, just hurt it, or miss it altogether. The optimal control solution is a sequence of motor commands that results in killing the animal by throwing the spear with minimal physical effort. If x denotes the state space (the positions and velocities of the muscles), the optimal control solution is a function u(x, t) that depends both on the actual state of the system at each time t and also explicitly on time.
The results from the JSS phase II static glass leaching experiments are presented. The experiments have been performed in the presence of bentonite, granite and stainless steel corrosion products at 90°C for 28 days. The leaching behaviour of Cs has been analysed using gamma-spectrometry. The surface of the leached glass samples has been analysed by infrared reflection spectrometry.
The presence of uncompacted bentonite seems to have a very small, increasing, effect on the leach rate of the glass compared to when no bentonite is present. In the presence of compacted bentonite, a lower leach rate has beep founy than in the prgsencelof uncompacted bentonite. (For Cs 0.3 g × m−2 × d−1 and 0.7 g × m−2 × d−1 respectively.) The addition of stainless steel corrosion products seems to have a slightly increasing effect on the leach rate in the presence of compacted bentonite. The beneficial effect of granite on the leach rate seems to be overshadowed by the presence of uncompacted bentonite.
The effects of the radiolysis of water exposed to mixed alpha- and beta-radiation originating from spent fuel have been calculated. The water is assumed to have penetrated the copper canister and fuel cladding, and then to exist as a 30 μm thin surface film on the fuel pellets.
The combined effects of alpha and beta-radiation, and the presence of iron in the water have been found to be important parameters. The beta-radiation will lower the yield of hydrogen, as will the presence of low concentrations of iron ions. The most likely conditions for water exposed fuel give rise to a total production of 1 mol H2 per m2 fuel surface after 1 million years. A stoichiometric amount of oxygen is also formed.
Calculations have also been carried out in connection with experiments on alpha-radiolysis from Am-241 or from spent fuel pellets. In the case of alpha-radiolysis from Am-241 it was calculated that a 20 cm2 thin layer of 4 mCi Am-241 produced 1.4 × 10−3 cm3 hydrogen per day.
Calculations simulating the conditions of experiments on the leaching of spent fuel have shown that both alpha- and gamma-radiation accelerate the dissolution. The rate is strongly dependent on the dose rate and on the area of the water film covering the fuel surface and fuel fissures.
A model for the radiation induced dissolution of U02has been developed and tested using experiments described in the literature. The model makes use of computer calculations based on a reaction mechanism in which the dissolution is initiated by reactions of H202, OH and H02 radicals with the U02surface. The model gave a fair agreement between calculated and experimental results: For a dose rate of 400 rad/s the calculated yields of oxidation were 2.6 and 2.1 % - h−1· m−2after 1 and 2 h, respectively. The corresponding experimental yields were 1.9 and 1.5 % ·h−1· m−2, when corrected for dissolution without irradiation. The effect of various initial concentrations of H202has been tested, and a reasonable rate constant for the reaction of U02and H202has been found. The requirement for the rate constant is that H202begins to be effective above concentrations of 10−3 mol · dm−3in accordance with experiments by L. Johnson.
The release of Am-241 during corrosion of the radioactive waste glass, JSS-A, has been studied in the presence of corrosion products and/or uncom-pacted bentonite. The corrosion behaviour of Am-241 has been analyzed using gamma spectrometry. Adsorption of Am-241 on bentonite is observed in all cases. The contents of Am-241 in centrifuged leachates are in most cases less than 1/100 of total values. The normalized elemental mass loss of Am increases initially with corrosion time, and the values in the presence of bentonite and corrosion products are larger than those in the presence of bentonite alone. This tendency is in agreement with results previously found for other elements. The release of Am is low, only about 10–20 % of the corresponding total mass loss.
In order to be able to model the effect of water radiolysis on the dissolution of fuel in the disposal vault it is essential to study the oxidation mechanism. Radiolysis of water produces radicals and molecules, amongst them the oxidizing species H2O2 and OH radicals, and, in aerated solutions, O2- as well. These species are probably responsible for the oxidation and dissolution of UO2 observed in a number of experiments. In the present investigation the effect of the oxidizing species has been studied separately using suitable scavengers. A polished specimen of UO2 was immersed in water and irradiated at ambient temperature with Co-60 gamma radiation. After irradiation the amount of uranium which had dissolved, or deposited elsewhere than the sample surface, was measured, and the oxidation of the surface was determined, using ESCA and SIMS. In 50 mM H2O2 (without irradiation) the corrosion rate was 5±3 μg.cm−2d−1 after 6 d exposure at pH 8. Corresponding rates for oxidation by O2- and OH radicals were about 3 μg.cm−2d−1, (dose rate 600±90 Gy/h.)
A joint research project with participation from
Japan, Switzerland and Sweden is underway at Studsvik (The JSS-project). The project concerns investigations on the leaching of fully radioactive glass (containing 12 wt% fission product oxides and actinide oxides) manufactured by CEA/Marcoule.
So far the glass has been leached in doubly distilled water and in silicate water at 90°C. Some leaching experiments involved the presence of crushed Stripa granite in the same containers as the glass.
Due to strong radiation and the presence of plutonium the leaching was carried out in a specially designed lead cave using gilded stainless steel containers.
Weight losses, pH and elemental mass losses were determined together with infrared reflection spectral changes. These data are compared to those obtained from a simulated nonradioactive glass of nearly the same composition and to similar alkali borosilicate glasses previously investigated at Studsvik.
A large number of computer calculations of the radiolysis of ground water outside copper canisters have been carried out within the Swedish Nuclear Fuel safety Project.
At dose rates higher than 5 × 10−2 rad/s the hydrggen concentration is constant, approximately 10−3 mol/dm3, and independent of time and dose rate. Therefore the rate of difiusion out of the system is constant, approximately 7 × 10−4 mol/year. At dose rates lower than 5 × 10−4 rad/s the logarithm of the hydrogen production is proportional to the logarithm of the dose rate. The hydrogen production depends on fuel type, burn-up and canister thickness only to the extent that the dose rate varies with these parameters. The hydrogen production is independent of the volume of water in which the energy is assumed to be absorbed (5 or 15 cm layers outside the surface of the canister).
The hydrogen production depends on the concentration of Fe2+ ions in the water. In the basic calculations the concentration was assumed to be 5 ppm. An increase to 50 ppm increases the total hydrogen production after one million years outside a 1 cm thick canister from 360 to 1000 mol. A decrease to 0.5 ppm decreases the same yield to 80 mol.
The leaching behavior of two alkali-borosilicate glasses containing 9 wt% simulated fission products and 1.6 wt% uranium oxide has been studied. Samples were exposed to one of eight types of leachants including doubly distilled water, simulated ground silicate water, a brine solution, and solutions containing various concentrations of iron, aluminium or sodium maintained at either 25°C, 40°C or 90°C for up to 182 days. The most aggressive leachants were the solutions containing sodium (excluding brine) and simulated ground silicate water. These solutions increased the extent of leaching by a factor of 2–3 over that for distilled water for one of the glasses. A partially protective surface film rich in magnesium potassium and chlorine was formed on the glasses exposed to the brine solution.
In order to evaluate the effects of atmosphere on leaching, samples were also immersed in doubly distilled water over which the relative concentrations of oxygen, nitrogen and carbon dioxide were varied. Increasing the carbon dioxide concentration from 0 to 50% resulted in a factor of 3 increase in the leaching rate.
The planned Swedish KBS glass corrosion investigation program comprises experiments with inactive glasses containing simulated waste, prolonged in-situ tests, the characterization of corrosion products, immiscibility studies, and corrosion experiments with “hot” glass.
This presentation gives a short description of the entire program. It focuses thereafter on some recent leaching results with the inactive KBS glass qualities ABS 39 and ABS 41, which were leached in a manner similar to the PNL MCC–1 test procedure.