Functionalization of synthetic polymers for potential use as biomaterials: selective growth of hydroxyapatite on sulphonated polysulphone.

A novel composite made of biocompatible synthetic polymer (Sulphonated Polysulphone, SPSPH) which may be easily fabricated in various shapes and synthetic hydroxyapatite (HAP) was prepared. The preparation was done by the spontaneous precipitation of HAP in aqueous suspensions of the polymer particles. The time the precipitation process was allowed to proceed was used to regulate the inorganic content of the composite. The preparation thus obtained, in addition to its effectiveness in inducing HAP formation, could be easily fabricated in various shapes, including films. The SPSPH-HAP composite films, surface area totaling ca. 30 cm2 induced the exclusive formation of HAP with rates proportional to the solution supersaturation. No induction times preceded the formation of HAP. Kinetics analysis with respect to HAP yielded an apparent order of precipitation of 6.0+/-0.4, suggesting polynuclear growth with the formation of nuclei above nuclei. The surface energy calculated from the rates of crystal growth on the polymeric substrate gave for HAP the value of 185 mJ m(-2) of order of magnitude typical for crystalline solids.

Effects of judicial instructions and case characteristics in a mock jury trial of battered women who kill.

This study examined the effects of judicial instructions on the outcome of a mock jury trial that involved a woman who pleaded self-defense after killing her abusive spouse. Jurors were instructed to adopt either an objective or a subjective standard of reasonableness when reaching a verdict. Within objective/subjective instruction conditions, half of the juries viewed a case in which the woman killed her abuser while he was attacking her (confrontational) and the remaining half viewed a case in which she killed him while he was asleep (no confrontation). Juries in the subjective conditions returned significantly more not guilty verdicts than jurors in the objective conditions. At the individual juror level, participants hearing subjective instructions were significantly more likely to rate the defendant as not guilty than jurors given objective instructions when the abuse was nonconfrontational.

Calculation of Zeta Potential from Electrokinetic Measurements on Titania Plugs.

The O'Brien theory developed for the electrical conductivity and electro-osmosis in porous plugs consisting of nonconducting particles has been applied for the calculation of zeta-potentials from conductivity and streaming potential measurements at two pH values, 3.3 and 6.5 or 5.8, on plugs composed of titania (undoped and doped with W6+ and Li+ ions) particles. The particles have been prepared both by precipitation (continuous crystallization at constant supersaturation) and by the sol-gel method. It was found that O'Brien's theory is also applicable in n-type semiconductor particles, such as titania (doped and undoped). Specifically, for the correct determination of zeta-potentials measured in solutions of relatively low ionic strength, it is necessary to take into account surface conduction behind the shear plane, for all samples measured at pH 3.3, a value considerably lower than the isoelectric point (i.e.p.) of titania. Under these conditions the surface charge of the suspended titania particles is high, and consequently the contribution of surface conductance to the conductivity of the plug is significant. The effect of surface conduction behind the shear plane on the calculation of zeta-potential is enhanced for the Li+-doped preparations due to the increase of surface conductivity caused by doping with Li+. Measurements of the streaming potential for the samples prepared with the sol-gel method were made at pH 6.5 (5.8 for the undoped titania); i.e., near the pH corresponding to the i.e.p., correct values of zeta-potential may be obtained in suspensions even at low ionic strength without taking into account the polarization of the double layer due to surface conduction, by applying the primitive Smoluchowski theory. This treatment is valid because at pH values near the i.e.p. the surface charge of the particles is very low, and consequently surface conductance is negligible compared with the conductivity of the plug. Copyright 1999 Academic Press.

Preliminary investigation of associations of illness schemata and treatment-induced reduction in headaches.

This study examined how illness schemata-ways people organize information about illness-change over the course of cognitive-behavioral treatment of chronic headache and the extent to which such changes predict reduction of headache. 73 subjects with chronic migraine, mixed migraine and tension, or tension headache were classified on the basis of outcome from imagery-based treatment as Treatment-responders (n = 24). Treatment nonresponders (n = 27), and Monitoring Controls (n = 22). Self-reported illness schemata related to the seriousness and changeability of headache were assessed at pretreatment and 8-wk. follow-up. While groups did not differ on pretreatment measures of illness schemata, at follow-up the Treatment responder group reported higher Changeability scores than Treatment-nonresponders and Control subjects and lower Seriousness scores than Control subjects. Headache reduction at follow-up was related to follow-up Changeability scores, in-session changes in systolic blood pressure and reported posttreatment expectations of headache activity, but not pretreatment measures of illness schemata. Findings indicate that improvements in headache activity are not influenced by the severity of headaches and may change prior to cognitive-behavioral treatment. Rather, among individuals who show decreases in headache activity, changes in beliefs about illness and headache reduction may have reciprocal relations both of which result from cognitive behavioral treatment.

Advances in the Mechanism of Deposition of MoO2-4 and Mo7O6-24 Species on the Surface of Titania Consisted of Anatase and Rutile

The mechanism of deposition of MoO2-4 and MoO7O6-24 from electrolytic solution on the surface of industrial titania consisting of anatase and rutile patches was further investigated following a recently developed methodology. The methodology is based on the "2pk/one site" and "triple-layer" models. It involves the writing down of various deposition equilibria, derivation of the corresponding equations, calculation of the amount of each of the deposited Mo(vi) species and the total amount of deposited Mo(vi) at various pH and concentrations, calculation of the variation with pH of the zeta potentials and of the difference in H+ ion consumption by the support surface in the presence and absence of MoO2-4 and Mo7O6-24 species in the impregnating solution. Comparison of the calculated parameters and variations mentioned above with the corresponding ones obtained by deposition experiments, potentiometric titrations, and microelectrophoresis allowed us to establish the mechanism of deposition of the Mo(vi) species on the surface of titania. It was found that the deposition of MoO2-4 and Mo7O6-24 species on the surface of "anatase regions" of the industrial titania takes mainly place by the following equilibria in the pH range 9.0-4.6: $ \displaylines{ \hfill\hbox{Ti}^{\rm a}\hbox{OH} + \hbox{MoO}^{2-}_{4} \leftrightarrow \hbox{Ti}^{\rm a}\hbox{--O--}(\hbox{MoO}_3)^- + \hbox{OH}^-\hfill\cr \hfill\hbox{Ti}^{\rm a}\hbox{OH}^+_2 + \hbox{MoO}^{2-}_4 \leftrightarrow \hbox{Ti}^{\rm a}\hbox{OH}^+_2 \cdots \hbox{MoO}^{2-}_4\hfill\cr \hfill\hbox{Ti}^{\rm a}\hbox{OH}^+_2 + \hbox{Mo}_7\hbox{O}^{6-}_{24} \leftrightarrow \hbox{Ti}^{\rm a}\hbox{OH}^+_2 \cdots \hbox{Mo}_7\hbox{O}^{6-}_{24}.\hfill\cr } $ According to this mechanism, in the pH range 9-7 the deposition takes place exclusively through the first equilibrium, namely, by reaction of the MoO2-4 ions, located in the inner Helmholtz place (IHP) of the double layer developed between the support surface and the impregnating solution, and the neutral surface hydroxyls in the "anatase regions" of the support. The deposition through adsorption of the MoO2-4 and Mo7O6-24 species, on the protonated surface hydroxyls of the support, starts at pH 7 and 6.4, respectively. The same equilibria are mainly responsible for the deposition on the rutile patches of the support, but the extent of deposition in this case is too small. A preference for deposition of MoO2-4 with respect to Mo7O6-24 ions was observed in almost the whole pH range studied. This was attributed to the negative charge developed in the IHP, which inhibits the location in it of highly charged Mo7O6-24 species. Lateral, attractive, interactions are exerted between the deposited Mo(vi) species through water molecules being in the IHP. The intensity of these interactions is proportional to the charge of the deposited Mo(vi) species.

Past-life identities, UFO abductions, and satanic ritual abuse: the social construction of memories.

People sometimes fantasize entire complex scenarios and later define these experiences as memories of actual events rather than as imaginings. This article examines research associated with three such phenomena: past-life experiences, UFO alien contact and abduction, and memory reports of childhood ritual satanic abuse. In each case, elicitation of the fantasy events is frequently associated with hypnotic procedures and structured interviews which provide strong and repeated demands for the requisite experiences, and which then legitimate the experiences as "real memories." Research associated with these phenomena supports the hypothesis that recall is reconstructive and organized in terms of current expectations and beliefs.

Multiple identity enactments and multiple personality disorder: a sociocognitive perspective.

People who enact multiple identities behave as if they possess 2 or more selves, each with its own characteristic moods, memories, and behavioral repertoire. Under different names, this phenomenon occurs in many cultures; in North American culture, it is frequently labeled multiple personality disorder (MPD). This article reviews experimental, cross-cultural, historical, and clinical findings concerning multiplicity and examines the implications of these findings for an understanding of MPD. Multiplicity is viewed from a sociocognitive perspective, and it is concluded that MPD, like other forms of multiplicity, is socially constructed. It is context bounded, goal-directed, social behavior geared to the expectations of significant others, and its characteristics have changed over time to meet changing expectations.

Cognitive-behavioral interventions for children's distress during bone marrow aspirations and lumbar punctures: a critical review.

Children with cancer often have difficulty coping with the invasive medical procedures that are part of diagnosis and treatment. Bone marrow aspirations and lumbar punctures are painful and cause some children severe anxiety and distress. The increased risk and expense of general anesthesia and the relative ineffectiveness of sedatives and anxiolytics has prompted clinicians to examine nonpharmacologic methods for controlling pain and distress. This report critically examines intervention studies that focus on cognitive-behavioral strategies such as distraction, imagery, or hypnosis for reducing procedural distress in children with cancer.

Response expectancies and interpretations as determinants of hypnotic responding.

Ss rated the extent to which they expected to respond to each of the suggestions on a hypnotizability scale both before and after the administration of the preliminary hypnotic induction procedure. After the induction, Ss also rated the extent to which they planned to respond actively and passively to each suggestion. Contrary to strong versions of response-expectancy theory, the extent to which Ss planned to adopt an active interpretation predicted behavioral and subjective indexes of hypnotizability even after controlling for the effects of postinduction expectations. In addition, an active interpretation significantly predicted response to suggestion for which Ss held weak and uncertain expectations. The relationship between expectation and hypnotizability was found to be fan-shaped rather than linear. Implications are discussed.

Close encounters: an examination of UFO experiences.

Ss who reported UFO experiences were divided into those whose experiences were nonintense (e.g., seeing lights and shapes in the sky) and those whose experiences were intense (e.g., seeing and communicating with aliens or missing time). On a battery of objective tests Ss in these 2 groups did not score as more psychopathological, less intelligent, or more fantasy prone and hypnotizable than a community comparison group or a student comparison group. However, Ss in the UFO groups believed more strongly in space alien visitation than did comparison Ss. The UFO experiences of Ss in the intense group were more frequently sleep-related than the experiences of Ss in the nonintense group. Among the combined UFO Ss, intensity of UFO experiences correlated significantly with inventories that assessed proneness toward fantasy and unusual sensory experiences. Implications are discussed.

Hypnosis, reporting bias, and suggested negative hallucinations.

We examined the role of reporting bias in hypnotic negative hallucinations by using a paradigm in which reporting bias was assessed independently of perceptual change. In Experiment 1, highly hypnotizable subjects reported significant loudness reductions when tested for hypnotic deafness. Later, however, these subjects biased their reported loudness reductions in the absence of perceptual change, and their reporting bias scores were almost as large as their hypnotic deafness reports. Subjects also biased their ratings of strategy use. In Experiment 2, ratings of blindness given in response to a hypnotic negative visual hallucination suggestion were significantly correlated with reporting bias scores obtained in this paradigm. Although hypnotic blindness and hypnotic deafness correlated significantly, the partial correlation between these variables was nonsignificant when reporting bias scores were statistically controlled. Theoretical implications are discussed.

EEG alpha methodologies and hypnotizability: a critical review.

This paper reviews empirical studies that assessed the relationship between EEG alpha indices and measures of hypnotic responding. Although there are confirmatory reports of such a relationship, these findings have not been corroborated in repeated attempts at replication. The research is characterized by poor design and statistical procedures that fail to control for various extraneous factors. Although a few positive findings have been tentatively identified, they await replication. Taken together, the available evidence suggests that hypnotizability is not systematically related to alpha.

Detection of simulated hypnotic amnesia.

Highly hypnotizable nonsimulators and high- and low-hypnotizable simulators of hypnosis were administered a hypnotic amnesia suggestion and tested for recall and recognition of a previously learned word list. Simulators exhibited higher levels of recall and recognition amnesia than nonsimulators. Most important, simulators recognized "forgotten" words at lower levels than expected by chance significantly more often than did nonsimulators. Implications for the detection of simulated amnesia in clinical samples are discussed.

Effectiveness of maximally different cognitive strategies and expectancy in attenuation of reported pain.

Ninety-six Ss rated pain during baseline and posttreatment exposures to cold pressor pain. Between trials, Ss in four groups were trained to use one of four cognitive coping strategies involving (a) imaginal reinterpretation, (b) imaginal distraction, (c) nonimaginal reinterpretation, or (d) nonimaginal distraction. Two additional groups were given: (e) an expectation for analgesia but no coping strategy and (f) no treatment. The four coping strategies produced equivalent attenuation of pain ratings and equivalent expectancies for analgesia. Expectancy control Ss expected analgesia, but reported no significant pain reductions. No treatment control Ss neither expected nor achieved any significant pain reductions. Among cognitive strategy groups, the Ss absorption added significantly to the variance in pain reduction above and beyond the effects of expectancy. Theoretical implications are discussed.

Effects of hypnotic, placebo, and salicylic acid treatments on wart regression.

Subjects with warts on their hands and/or feet were randomly assigned to a hypnotic suggestion, topical salicylic acid, placebo, or no treatment control condition. Subjects in the three treated groups developed equivalent expectations of treatment success. Nevertheless, at the six-week follow-up interval only the hypnotic subjects had lost significantly more warts than the no treatment controls. Theoretical implications are discussed.

Cognitive mediators in the reduction of pain: the role of expectancy, strategy use, and self-presentation.

Eighty subjects underwent three trials of cold-pressor pain. The first cold-pressor trial served as a baseline. Next, subjects in a neutral (no expectancy information) condition were taught a distraction strategy (shadowing letters) before one cold-pressor trial and an imagery strategy before the other. Subjects in other conditions received positive expectancy information about one of the strategies and negative expectancy information about the other. Negative information reduced expectancy ratings and decreased the magnitude of reported pain reductions. Both pretested levels of social desirability and degree of absorption in strategy use made contributions to the prediction of pain reduction that were independent of expectancy ratings. Theoretical implications are discussed.

Hypnosis, suggestion, and placebo in the reduction of experimental pain.

Two experiments compared placebo and hypnotic analgesia in high and low hypnotizable subjects. Experiment 1 demonstrated that hypnotic and placebo analgesia were equally ineffective in low hypnotizables, but that hypnotic analgesia was much more effective than placebo analgesia in high hypnotizables. Experiment 2 replicated these results, but also included low and high hypnotizables who were given a nonhypnotic suggestion for analgesia. Both the low and high hypnotizables in this group reported greater suggested than placebo analgesia and as much suggested analgesia as high hypnotizable hypnotic subjects. Both experiments found substantial discrepancies between the amount of pain reduction subjects expected from the various treatments and the amount of pain reduction they actually reported following exposure to those treatments. In Experiment 2, subjects in all treatments who reduced reported pain engaged in more cognitive coping and less catastrophizing than those who did not reduce pain. Theoretical implications are discussed.

Psychosocial variables associated with willingness to donate organs.

Questionnaires were administered to 108 university psychology students to investigate attitudes and behaviour related to organ donation. Three groups (committed, uncommitted and opposed) were identified. A multivariate analysis of variance showed that, compared with uncommitted donors, committed donors felt better informed about organ donation, had discussed donation more often with family members and knew more people who had signed donor cards. The subjects in the opposed group and those in the uncommitted group cited different reasons for not signing a donor card. Empathy, religious beliefs and attitudes about death did not affect willingness to donate. Analyses of the interaction between willingness to donate one's own organs and willingness to donate those of a family member revealed a monotonic increase in willingness to donate the organs of a family member as the type of recipient became more personally relevant. Our findings indicate that when health care professionals request donor organs the potential recipients must be presented to the potential donors in a personally relevant manner. Educational programs must be developed to train medical personnel in how to effectively ask for organs without coercing the potential donor or invading the privacy of the potential recipient.

Effects of instructional set on attributions of nonvolition during hypnotic and nonhypnotic analgesia.

Fifty highly hypnotizable subjects were assigned to four treatment groups or a no-treatment control group and then underwent two pain stimulation trials. Half the treated subjects were administered hypnotic analgesia, half waking analgesia. Within hypnotic and nonhypnotic treatments, half the subjects were given actively worded analgesia instructions, half passively worded instructions. Subjects in the four treated groups reported equivalent pain reduction and equivalent use of coping imagery, although hypnotic subjects rated themselves as more deeply hypnotized than did nonhypnotic subjects. Both hypnotic and nonhypnotic subjects given passive instructions rated their pain reduction as occurring involuntarily, whereas those given active instructions reported that their pain was reduced through their active use of coping strategies. These findings support sociocognitive formulations of hypnotic responding that view ratings of involuntariness as reflecting contextually guided interpretations of behavior.