Microstructure and Properties of Fe<Subscript>3</Subscript>Al-Fe<Subscript>3</Subscript>AlC<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> Composite Prepared by Reactive Liquid Processing

A Fe₃Al-Fe₃AlC _x composite was prepared using reactive liquid processing (RLP) through controlled mixture of carbon steel and aluminum in the liquid state. The microstructure and phases of the composite were assessed using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, optical microscopy, and differential scanning calorimetry. In addition, the density, hardness, microhardness, and elastic modulus were evaluated. The Fe₃Al-Fe₃AlC _x composite consisted of 65 vol pct Fe₃Al and 35 vol pct Fe₃AlC _x (κ). The κ phase contained 10.62 at. pct C, resulting in the stoichiometry Fe₃AlC_0.475. The elastic modulus of the Fe₃Al-Fe₃AlC_0.475 composite followed the rule of mixtures. The RLP technique was shown to be capable of producing Fe₃Al-Fe₃AlC_0.475 with a microstructure and properties similar to those achieved using other processing techniques reported in the literature.     

Emotional catharsis and aggression revisited: Heart rate reduction following aggressive responding.

The authors tested two components of the catharsis theory of aggression: physiological tension reduction and aggressive drive reduction. On the basis of work in the stress-aggression literature, they also examined the moderating effect of impersonal stress exposure on cathartic reductions in heart rate following aggressive responding. Participants were instructed to administer nonaggressive (correct button) or aggressive (shock button) responses to a frustrating confederate in a laboratory aggression paradigm, and half the participants were exposed to an impersonal stressor (aversive air blasts) during the procedure. Heart rate was recorded before and after the participants administered the aggressive or nonaggressive response. Analyses revealed that participants exhibited reductions in heart rate following aggressive but not nonaggressive responding, but this was the case only for those not exposed to the impersonal stressor. Heart rate reductions during the experimental blocks actually predicted the most intense aggression in a subsequent block of trials. The results are considered in light of different theories of aggression by J. E. Hokanson (1974) and L. Berkowitz (1990) and have implications for interventions with anger-prone individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Intergenerational Transmission of Externalizing Behaviors in Adult Participants: The Mediating Role of Childhood Abuse.

Childhood abuse was investigated as a potential mediator of the intergenerational transmission of externalizing behaviors (EXT) in adulthood among a large general population sample drawn from the National Comorbidity Survey. Community participants (N = 5,424) underwent diagnostic and psychosocial interviews and reported on their own adult symptoms of antisocial behavior and substance dependence, parental symptoms, and childhood abuse history. Multiple group structural equation modeling revealed that (a) EXT in parents was associated with childhood abuse in offspring, particularly among mother- daughter dyads, (b) abuse had a unique influence on adult EXT in offspring above parental EXT, and (c) abuse accounted for the relationship between parental EXT and offspring EXT in female but not male participants. This article emphasizes the importance of examining different environmental processes which may explain familial transmission of destructive behaviors in men and women and highlights the importance of family interventions that target parental symptoms to ameliorate risk to offspring. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stress-induced asymmetric frontal brain activity and aggression risk.

Impersonal stressors, not only interpersonal provocation, can instigate aggression through an associative network linking negative emotions to behavioral activation (L. Berkowitz, 1990). Research has not examined the brain mechanisms that are engaged by different types of stress and serve to promote hostility and aggression. The present study examined whether stress exposure elicits more left than right frontal brain activity implicated in behavioral approach motivation and whether this lateralized brain activity predicts stress-induced aggression and hostile/aggressive tendencies. Results showed that (a) participants in the impersonal (assigned to stress by a computer) and interpersonal (assigned to stress by a provoking confederate) stress conditions both showed more left than right frontal electroencephalogram activity after condition assignment and stress exposure and (b) the 2 stress groups exhibited subsequent increases in aggression relative to the no-stress group. Importantly, left frontal asymmetry in response to stress exposure predicted increases in subsequent aggressive behavior, a finding that did not emerge in the no-stress condition. Thus, both the interpersonal and impersonal stressors impacted state changes in brain activity related to behavioral approach, suggesting that stress reactivity involving approach activation represents risk for behavioral dysregulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences in emotional risk for self- and other-directed violence among externalizing adults.

Objective: Women and men generally differ in how frequently they engage in other- and self-directed physical violence and may show distinct emotional risk factors for engagement in these high-impact behaviors. To inform this area, we investigated gender differences in the relationship of emotional tendencies (i.e., anger, hostility, and anhedonic depression) that may represent risk for other-directed violence (i.e., physical fighting, attacking others unprovoked) and self-directed violence (i.e., self-injury, suicide attempts). Method: The ethnically diverse sample consisted of 372 adults (252 men and 120 women age 18–55) with a history of criminal convictions. Facets of emotional risk assessed with the Aggression Questionnaire (Buss & Warren, 2000) and Mood and Anxiety Symptom Questionnaire (Watson et al., 1995) were entered simultaneously as explanatory variables in regression analyses to investigate their unique contributions to other- and self-directed physical violence in men and women. Results: Analyses revealed that anhedonic depressive tendencies negatively predicted other-directed violence and positively predicted self-directed violence in men and women, consistent with a model of depression in which aggression is turned inward (Henriksson et al., 1993). Gender differences, however, emerged for the differential contributions of anger and hostility to other- and self-directed violence. Trait anger (i.e., difficulty controlling one's temper) was associated with other-directed violence selectively in men, whereas trait hostility (i.e., suspiciousness and alienation) was associated with self- and other-directed violence among women. Conclusions: The divergent findings for trait anger and hostility underscore the need to examine gender-specific risk factors for physical violence to avoid excluding potentially useful clinical features of these mental health outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis and characterization of side-chain maleimide-styrene copolymers with new pendant azobenzene moieties

Four side-chain maleimide-styrene polymers have been synthesized from maleimide-alt-styrene copolymer (MASt) and some original azo-moieties using polymer analogous reactions. The structures have been obtained with good yields; remarkably, they showed a high chromophore load, up to ~100%. The polymers were characterized by means of SEC, FT-IR, ¹H-NMR, DSC-TGA, and elemental analysis. The side-chain polymers exhibited improved solubility and enhanced thermal stability up to 320oC, while their glass transition temperatures have been found to be as high as 210oC. The third-order NLO refraction (n₂) and susceptibility χ⁽³⁾ coefficients were measured by Z-scan technique. The results of Z-scan measurements showed that the polymers have only nonlinear refraction, the nonlinear absorption being negligible.     

Synthetic single crystal diamond dosimeters for conformal radiation therapy application

A synthetic single crystal diamond based dosimeter in a p-type/intrinsic/metal structure, operating in photovoltaic regime, is proposed for application in highly conformed radiotherapy dosimetry. The device was characterized by using 6 and 10 MV Bremsstrahlung X-ray beams and electron beams from 6 MeV up to 18 MeV, obtained by a CLINAC DHX Varian accelerator. All measurements were performed in a water phantom and commercial ionization chambers were used for calibration and comparison. Results showed a very good agreement of the diamond device response, as compared with the reference dosimeters, fast response times and high spatial resolution. One of such diamond dosimeters was then tested using a real Intensity Modulated Radiation Therapy (IMRT) prostate cancer treatment plan and its performance was compared with the ones from ionization chambers and a 2D diode array. The obtained results clearly assess the suitability of synthetic single crystal diamond for dose measurements in highly conformed radiotherapy and particularly in IMRT applications.     

Extreme UV photodetectors based on CVD single crystal diamond in a p-type/intrinsic/metal configuration

We report on extreme UV (EUV) photodetectors based on CVD single crystal diamond in a p-type/intrinsic/metal configuration fabricated and tested at Roma “Tor Vergata” University laboratory, operating in a sandwich geometry. Particular care has been devoted to the design of the device geometry in order to take advantage of the internal junction electric field and to minimize the signal contribution arising from secondary electron emission, which is known to strongly affect the detection properties in the UV and EUV regions. The device has been characterized in the EUV spectral region by using both He and He–Ne DC gas discharge radiation sources and a toroidal grating vacuum monochromator, with 5 Å wavelength resolution. The reproducibility test has been performed on several photodetectors showing a high uniformity of the device performances. The devices showed negligible undesired effects such as persistent photocurrent and memory effects, resulting in extremely promising stability features of the p-type/intrinsic/metal structured device. The devices have been tested at different bias voltages between 0 and 15 V, showing the best performances at 0 bias voltage. Finally, the external quantum efficiency (EQE), as well as the responsivity have been measured in the range 20 to 100 nm.     

Influence of dietary egg and soybean phospholipids and triacylglycerols on human serum lipoproteins

The online version of the original article can be found at