Direct inkjet printing of dental prostheses made of zirconia.

CAD/CAM milling systems provide a rapid and individual method for the manufacturing of zirconia dental restorations. However, the disadvantages of these systems include limited accuracy, possible introduction of microscopic cracks, and a waste of material due to the principle of the 'subtractive process'. The hypothesis of this study was that these issues can be overcome by a novel generative manufacturing technique, direct inkjet printing. A tailored zirconia-based ceramic suspension with 27 vol% solid content was synthesized. The suspension was printed on a conventional, but modified, drop-on-demand inkjet printer. A cleaning unit and a drying device allowed for the build-up of dense components of the size of a posterior crown. A characteristic strength of 763 MPa and a mean fracture toughness of 6.7 MPam(0.5) were determined on 3D-printed and subsequently sintered specimens. The novel technique has great potential to produce, cost-efficiently, all-ceramic dental restorations at high accuracy and with a minimum of materials consumption.

Is there a real danger of concealing gunshot residue (GSR) particles by skin debris using the tape-lift method for sampling GSR from hands?

Experiments were carried out to assess the danger of concealing GSR particles by skin debris using the tape-lift method for sampling GSR from hands. Thirty discrete spherical particles (from GSR and from the debris of oxygen cutting of steel) sized from 8 to 30 microns were mounted on a double-side adhesive coated stubs in known locations using a stereomicroscope. These stubs were then used for dabbing hands 50 times. Some of the particles or parts thereof were covered by skin flakes, however, all particles could be detected using the backscattered electron image (BEI) in the scanning electron microscope (SEM). Also, all could be identified by the energy dispersive X-ray spectroscopy (EDX).

Machine washing or brushing of clothing and its influence on shooting distance estimation.

Experiments were conducted to assess the effect of machine washing or brushing of clothing items on Gunshot Residue (GSR) patterns (gunpowder residues, lead, and copper, deposits) around bullet entrance holes. Results show that those treatments decrease considerably the amount and density of GSR. However, for close shooting distances not all of the GSR deposits are removed. Remaining patterns may be visualized by specific color reactions and used for shooting distance estimation.

Immunochemical approaches for purification and detection of TNT traces by antibodies entrapped in a sol-gel matrix.

A highly sensitive immunochemical method for immunoaffinity purification (IAP) and detection of trace amounts of TNT was developed on the basis of antibodies (Abs) in a ceramic matrix (sol-gel). The study resulted in: (i) a highly sensitive and reproducible TNT ELISA (I50 and I20 values of 0.4 +/- 0.09 ppb and 0.12 +/- 0.03 ppb, respectively; n = 12), which is highly specific to TNT; and (ii) successful entrapment of the Abs that bound free analyte from solution. Binding was found to be highly reproducible, dose dependent, and only slightly (1.2-1.8-fold) lower than that in solution. The entrapped Abs did not leach from the matrix and were tolerant of absolute ethanol, acetone, and acetonitrile. Bound analytes could be easily eluted from the sol-gel matrix at high recoveries. The sol-gel-based IAP method described above introduces a simple one-step procedure that has a high potential to serve as a suitable and convenient immunochromatographic device for cleanup and concentration of TNT from "real field" samples in a manner that complies with both chemical and immunochemical residue analysis methods.

Effects of nicotine deprivation and irritability on physical aggression in male smokers.

Thirty-five continuing male smokers were randomly assigned to either a deprived or a nondeprived condition. On the basis of self-reported trait irritability, participants were then assigned to 1 of 4 groups: deprived-high irritable, deprived-low irritable, nondeprived-high irritable, and nondeprived-low irritable. Aggression was measured with a modified version of the Taylor aggression paradigm. Self-reported smoking urge was assessed throughout the reaction time competition. Results indicated that the deprived-high-irritable group displayed the highest levels of aggressive behavior. Positive associations between urge ratings and aggression indexes were detected only in the deprived-high-irritable group. Results support the existence of an interactive effect of nicotine deprivation and trait irritability on physical aggression and highlight the role of smoking urge as an important factor in the deprivation-aggression link.

Homophobia and physical aggression toward homosexual and heterosexual individuals.

This study examined the relationship between homophobia (defined as self-reported negative affect, avoidance, and aggression toward homosexuals) and homosexual aggression. Self-identified heterosexual college men were assigned to homophobic (n = 26) and nonhomophobic (n = 26) groups on the basis of their scores on the Homophobia Scale (HS; L. W. Wright, H. E. Adams, & J. A. Bernat, 1999). Physical aggression was examined by having participants administer shocks to a fictitious opponent during a competitive reaction time (RT) task under the impression that the study was examining the relationship between sexually explicit material and RT. Participants were exposed to a male homosexual erotic videotape, their affective reactions were assessed, and they then competed in the RT task against either a heterosexual or a homosexual opponent. The homophobic group reported significantly more negative affect, anxiety, and anger-hostility after watching the homosexual erotic videotape than did the nonhomophobic group. Additionally, the homophobic group was significantly more aggressive toward the homosexual opponent, but the groups did not differ in aggression toward the heterosexual opponent.

Improved method for shooting distance estimation. Part III. Bullet holes in cadavers.

An improved method to estimate firing distance on human body surfaces is described. The novel part of the method includes a chemical test in addition to the traditional visual and microscopic examinations of the gunshot wounds. This chemical test consists of a transfer of the gunpowder residues from the area of a gunshot wound to an adhesive lifter; the residues are then visualized as total nitrite after alkaline hydrolysis by the Modified Griess Test (MGT). When cadavers are in an advanced stage of decomposition or when gunshot wounds are in hairy areas, the information obtained by this chemical test can be crucial for shooting distance evaluation. In other cases it may improve the accuracy of the examination. In some cases, the results obtained by this test may assist in the discrimination between entrance and exit gunshot wounds.

Improved method for shooting distance determination. Part 2--bullet holes in objects that cannot be processed in the laboratory

An improved method for firing distance determination on exhibits that cannot be processed in the laboratory such as cars, doors, windows, or furniture is described. The novel part of the method includes transfer of total nitrite (nitrite ions and smokeless powder residues) from the target to an adhesive lifter. After the transfer, vaporous lead and copper deposits around the bullet entrance hole are visualized on the target by sodium rhodizonate and rubeanic acid, respectively. The Modified Griess Test is carried out after alkaline hydrolysis of the smokeless powder residues on the adhesive lifter.

Improved method for shooting distance estimation. Part 1. Bullet holes in clothing items

An improved method for firing distance estimation on clothing is described. The novel part of the method includes transfer of total nitrite (nitrite ions and smokeless powder residues) from the target to an adhesive lifter. After the transfer, lead and copper deposits around the bullet entrance hole are visualized by rhodizonate and rubeanic acid, respectively. The Modified Greiss Test is carried out after alkaline hydrolysis of the smokeless powder residues on the adhesive lifter.

Sex differences in pain indices, exercise, and use of analgesics.

To understand better reported sex differences in sensitivity to pain, this study examined daily pain frequency and intensity, use of analgesics, physical activity, and both subjective and physiological response to acute pain in 18 men and 24 women, healthy people who provided information about their daily pain symptoms and physical activity before completing a cold pressor task. Compared to men, women reported more frequent and intense pain symptoms, as well as more frequent use of analgesics and lower physical activity. Women evinced higher physiological arousal during the cold pressor task but similar subjective pain. The findings highlight the different ways men and women cope with pain and the effect on their responses to acute pain.

Contributing factors in the aggressive crisis.

Uncontrollable acts of violence, or "aggressive crises," result from one's reduced ability to regulate the expression of aggressive behavior in interpersonal situations. Identification of factors that predict the risk for violence is extremely important to emergency mental health providers in the field. This article discusses psychiatric, constitutional, and situational factors associated with potentiating the aggressive crisis. Based on the literature reviewed it can be argued that it is important to understand constitutional factors that contribute to the propensity of a given client to behave aggressively and that these factors interact with a wide range of situational determinants. While the aggressive crisis should be anticipated when certain conditions are met, its occurrence remains difficult to predict.

Effects of familial pain models on daily pain indices and performance during the cold pressor task.

To understand better the role of pain history in current response to pain episodes, this research examined pain-related indices from the patient's family of origin and their relationships to the patient's coping with acute pain. Participants were 42 healthy men and women who provided information about their own and their family's pain history and then were administered a cold pressor task. High frequency of family pain modeling was associated with higher frequency of current pain episodes, more types of pain, greater intensity, and also lower physiological arousal and subjective pain ratings during the cold pressor. The findings underscore the relationships between familial pain modeling and current pain-related functioning.

Measurement of laboratory aggression: a new response-choice paradigm.

40 undergraduate student volunteers were tested on a new Response-choice Aggression Paradigm. Men and women were provoked in a reaction time competition by receiving electric shocks and were allowed to respond to a confederate with similar shocks or to refrain from any retaliation. Analysis indicated positive association between a self-report measure of physical aggression and laboratory responses on the paradigm, and positive associations among aggression indices of the task. The results confirm earlier findings of sex differences in aggression and offer new measures of aggression "flashpoint" as a step closer to aggressive behavior in naturalistic settings.

Effects of frequency of pain report on subjective pain ratings of the cold pressor task.

Differences in methodology among studies using the cold pressor task have affected the level of pain reported by subjects. This study was designed to assess the effects of varying frequency of self-report on intensity of subjective pain ratings. In a sample of 108 subjects, significant differences in pain ratings were found between subjects who rated their pain at 50-sec. intervals and groups who rated at lower or higher frequencies. Analysis indicated that the frequency of reporting pain may influence the coping strategies used by patients with pain and should be considered carefully by researchers.

Alcohol-induced stimulation and sedation: relation to physical aggression.

The relation between the stimulating and the sedating effects of acute alcohol consumption on human physical aggression was examined. Sixty male social drinkers were assigned to either an alcohol or a sober group. Aggression was measured using a modified version of S. Taylor's (1967) aggression paradigm, in which electric shocks are received from and administered to a fictitious opponent during a competitive task. Aggression was operationalized as the intensity and the duration of the shocks selected. Stimulation and sedation were measured using a self-report inventory. Results demonstrated that stimulation was positively related to aggression, but only in the intoxicated state. Sedation was not related to aggression in either the intoxicated or the sober state.

The biphasic effects of alcohol on human physical aggression.

The authors assessed the biphasic effects of alcohol on human physical aggression. Sixty male social drinkers were assigned to 1 of 4 groups: alcohol ascending limb (AAL), alcohol descending limb (ADL), or 1 of 2 sober control groups. Aggression was assessed in the AAL and ADL groups at respective ascending or descending blood alcohol concentrations (BAC) of 0.08%. Each participant in the control groups was respectively yoked with a participant in either the AAL or the ADL group to control for the longer period of time needed to reach a BAC of 0.08% on the descending limb compared with the ascending limb (i.e., passage of time effect). The authors measured aggression using a modified version of the Taylor aggression paradigm (S. Taylor, 1967), in which electric shocks are received from and administered to a fictitious opponent during a competitive task. The AAL group was more aggressive than the ADL groups. There were no differences between the ADL group and the control groups, which suggests that alcohol does not appear to increase aggression on the descending limb. The control groups did not differ in aggression, thus ruling out a passage of time effect.

Temperament, hostility, and consequences of alcohol use.

Problems in temperament and hostility have been implicated in alcohol use disorders. This study investigated the relationships among temperament, hostility, and adverse consequences of alcohol consumption in a sample of 180 healthy young social drinkers. Rigid behavior pattern and antagonistic hostility were positively correlated with adverse consequence of drinking.

Bradycardia during baroreflex stimulation and active or passive stressor tasks: cardiorespiratory fitness and hostility.

We examined whether the resting bradycardia associated with cardiorespiratory fitness extends to lowered heart rate (HR) and mean arterial pressure during novel passive or active laboratory stressors and to a longer heart period during stimulation of the carotid-cardiac vagal baroreflex, independently of the Type A behavior pattern (TABP) and hostility. Forty-four normotensive Caucasian men (18-35 years of age) completed the Structured Interview for TABP, the Cook-Medley Hostility Scale, and a peak oxygen uptake (Vo2peak) test. Vo2peak was inversely related to HR prior to, during, and after each stressor and was positively related to heart period during baroreflex testing. Hostility was inversely related to heart period during baroreflex testing. TABP had no effects. Our findings indicate that cardiorespiratory fitness and low hostility are independently associated with a bradycardia during stimulation of the carotid-cardiac baroreflex, consistent with a possible enhancement of cardiac vagal tone.

Relation between executive cognitive functioning and the adverse consequences of alcohol use in social drinkers.

The purpose of this study was to assess the relation between Executive Cognitive Functioning (ECF) and the adverse consequences of alcohol consumption. ECF encompasses "higher order" cognitive abilities involved in goal-directed behavior, such as attentional control, mental flexibility, planning, and self-monitoring. Impaired ECF has been shown to result in a variety of negative consequences, including excessive drug and alcohol use. Subjects were 79 nonalcoholic male social drinkers between 17 to 30 years of age. ECF was measured using three neuropsychological tests: the Wisconsin Card Sorting Test (WCST), the Conditional Associative Learning Test (CAT), and the Sequential Matching Memory Test (SMMT). Adverse drinking consequences were measured using the Drinker Inventory of Consequences (DrInC). The DrInC assesses drinking consequences in five domains: Physical, Intrapersonal, Interpersonal, Social Responsibility, and Impulse Control. Scores from the neuropsychological tests were reduced into two latent variables: one representing the WCST and the other representing the CAT and SMMT. The results indicated that errors on the CAT/SMMT variable were positively related to adverse consequences in each domain, except for physical consequences. A similar association was found between the WCST variable and impulse control consequences. These findings indicate that performance on tests measuring ECF is related to the severity of drinking consequences. Therefore, prevention and treatment outcomes may be improved by incorporating cognitive habilitation into current interventions.

Casework experience of GSR detection in Israel, on samples from hands, hair, and clothing using an autosearch SEM/EDX system.

Casework experience in the detection of GSR particles on samples from hands, hair and clothing is reported for the period of 6 years (1989-1994). The overall "success" rate on the examined samples is about 10%. Aspects of the sampling procedures, the number of particles detected per sample and problems of possible contamination are discussed.