X-Ray Emission from the Warm Hot Intergalactic Medium

The number of detected baryons in the Universe at z<0.5 is much smaller than predicted by standard big bang nucleosynthesis and by the detailed observation of the Lyman alpha forest at red-shift z=2. Hydrodynamical simulations indicate that a large fraction of the baryons today is expected to be in a ``warm-hot'' (10^5-10^7K) filamentary gas, distributed in the intergalactic medium. This gas, if it exists, should be observable only in the soft X-ray and UV bands. Using the predictions of a particular hydrodynamic model, we simulated the expected X-ray flux as a function of energy in the 0.1-2 keV band due to the Warm-Hot Intergalactic Medium (WHIM), and compared it with the flux from local and high red-shift diffuse components. Our results show that as much as 20% of the total diffuse X-ray background (DXB) in the energy range 0.37-0.925keV could be due to X-ray flux from the WHIM, 70% of which comes from filaments at redshift z between 0.1 and 0.6. Simulations done using a FOV of 3', comparable with that of Suzaku and Constellation-X, show that in more than 20% of the observations we expect the WHIM flux to contribute to more than 20% of the DXB. These simulations also show that in about 10% of all the observations a single bright filament in the FOV accounts, alone, for more than 20% of the DXB flux. Red-shifted oxygen lines should be clearly visible in these observations.Comment: 19 pages, 6 figure

3D printing and immersive visualization for improved perception of ancient artifacts

This article investigates the use of 3D immersive virtual environments and 3D prints for interaction with past material culture over traditional observation without manipulation. Our work is motivated by studies in heritage, museum, and cognitive sciences indicating the importance of object manipulation for understanding present and ancient artifacts. While virtual immersive environments and 3D prints have started to be incorporated in heritage research and museum displays as a way to provide improved manipulation experiences, little is known about how these new technologies affect the perception of our past. This article provides first results obtained with three experiments designed to investigate the benefits and tradeoffs in using these technologies. Our results indicate that traditional museum displays limit the experience with past material culture, and reveal how our sample of participants favor tactile and immersive 3D virtual experiences with artifacts over visual non-manipulative experiences with authentic objects. This paper is part of a larger study on how people perceive ancient artifacts, which was partially funded by the University of California Humanities Network and the Center for the Humanities at the University of California, Merced.This is the author accepted manuscript. The final version is available from MIT Press via http://dx.doi.org/10.1162/PRES_a_0022

A Microcalorimeter and Bolometer Model

The standard non-equilibrium theory of noise in ideal bolometers and microcalorimeters fails to predict the performance of real devices due to additional effects that become important at low temperature. In this paper we extend the theory to include the most important of these effects, and find that the performance of microcalorimeters operating at 60 mK can be quantitatively predicted. We give a simple method for doing the necessary calculations, borrowing the block diagram formalism from electronic control theory.Comment: 20 pages, 15 figure

Historical micronutrient psychiatry: descriptive analysis of patients with pellagra admitted to the “San Lazzaro” asylum in Reggio Emilia (Italy) in the decade 1901-1910

This study aims at describing the socio-demographic and clinical characteristics of the patients affected by pellagra and admitted to the “San Lazzaro” psychiatric asylum (Reggio Emilia, Italy) from 1901 to 1910 besides exploring possible gender differences for the collected information. Data were collected from the admission register and clinical records of those patients who were admitted to the San Lazzaro Psychiatric Hospital receiving a diagnosis of pellagra at their first admission. The pellagrous patient population was characterised by a higher rate of hospitalisation for women (64.3%) and the number of hospitalised patients suffering from pellagra gradually decreased from 1901 (78; 8.3%) to 1910 (8;0.7%). The most common profession for men admitted with pellagra was farmer/agricultural labourer, while most of the women were housewives. A characteristic shared by both the male and female population of inpatients was very high rate of illiteracy: only one patient was recorded as being able to read and write. The generic diagnosis of “mental illness from pellagra” was predominant (70%), while “dementia from pellagra” accounts for 17.85% of the admission diagnoses: no statistically significant differences between men and women were found in the frequency of diagnosis. Half of the patients, both men and women, died while being inpatients. This study confirms previous findings about the case mix of pellagra patients admitted to psychiatric hospital at the beginning of the last century in northern Italy and highlights the significance of the relationship of psychiatry with other medical disciplines and the sociocultural milieu

Characterisation of ‘Starking’ apple polyphenoloxidase

Experiments were performed to optimise the extraction conditions of “StarkingÏ apple fruit polyphenoloxidase (PPO), to evaluate the affinity and speciÐcity towards several substrates and to study the stability of enzyme extracts from apple samples stored under di†erent conditions. Sodium phosphate bu†er (0É2 M, pH 6É5) plus 0É25% Triton X and 1% or 2% PVPP was found to be the most efficient extraction mediu10m0. Chlorogenic acid, dopamine and 4- methylcatechol showed similar speciÐcity towards PPO, and chlorogenic acid was found to be the best substrate for the enzyme. Enzyme extracts from frozen cut apple stored at [4¡C, and extracts from lyophilised apple samples stored at 4¡C were more stable than extracts obtained from fresh-cut or acetone powder sample

Transition Between Sensitive Delusion of Reference and Mood Disorder: A Case Report

The Sensitive Delusion of Reference is a clinical entity described by Ernst Kretschmer and never integrated into mainstream nosographic systems. It represents the possibility of developing psychosis starting from a personality characterized by sensitivity, scrupulousness, and fear of judgment of others. The presentation of the following clinical case highlights how the overlap between this clinical entity and mood disorders leads to characteristic psychopathology, which has not been sufficiently detailed. In particular, the delusions, which always starts from the idea of reference and the shame in the face of the judgment of others, takes on characteristics of guilt during the depressive phases and persecutory themes during the activation phases. This clinical observation, which obviously needs to be confirmed on a larger scale, encourages a renewed interest in the concept of Kretschmer's Sensitive Delusion of Reference and creates the possibility of intersecting multiple psychopathological levels, for a more complete perspective on the individual case

Can stigmatizing attitudes be prevented in psychology students?

Background: Stigmatizing attitudes have been found among psychology students in many studies, and they are becoming more common with time. Aims: This study examines whether participation in clinical psychology lessons reduces levels of stigmatization in a population of psychology students and whether it leads to any change in stigmatization. Methods: The study is a pre/post evaluation of the effectiveness of clinical psychology lessons (63 hours of lectures) as a tool to fight stigma. The presence of stigmatizing attitudes was detected using the Italian version of the Attribution Questionnaire-27 (AQ-27-I). Stigmatization was described before and after the lessons with structured equation modeling (SEM). Results: Of a total of 387 students contacted, 302 (78.04%) agreed to be involved in the study, but only 266 (68.73%) completed the questionnaires at both t0 and t1. A statistically significant reduction was seen in all six scales and the total score on the AQ-27-I. The models defined by the SEM (pre- and post-intervention) showed excellent model fit indices and described different dynamics of the phenomenon of stigma. Conclusions: A cycle of clinical psychology lessons can be a useful tool for reducing stigmatizing attitudes in a population of students seeking a psychology degree

Observed Limits on Charge Exchange Contributions to the Diffuse X-ray Background

We present a high resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV for a ~1 region of the sky centered at l=90, b=+60 using a 36-pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum's observed line ratios help separate charge exchange contributions originating within the heliosphere from thermal emission of hot gas in the interstellar medium. The X-ray sensitivity below 1 keV was reduced by about a factor of four from contamination that occurred early in the flight, limiting the significance of the results. The observed centroid of helium-like O VII is 568+2-3 eV at 90% confidence. Since the centroid expected for thermal emission is 568.4 eV while for charge exchange is 564.2 eV, thermal emission appears to dominate for this line complex, consistent with much of the high-latitude O VII emission originating in 2-3 x 10^6 K gas in the Galactic halo. On the other hand, the observed ratio of C VI Ly gamma to Ly alpha is 0.3+-0.2. The expected ratios are 0.04 for thermal emission and 0.24 for charge exchange, indicating that charge exchange must contribute strongly to this line and therefore potentially to the rest of the ROSAT R12 band usually associated with 10^6 K emission from the Local Hot Bubble. The limited statistics of this experiment and systematic uncertainties due to the contamination require only >32% thermal emission for O VII and >20% from charge exchange for C VI at the 90% confidence level. An experimental gold coating on the silicon substrate of the array greatly reduced extraneous signals induced on nearby pixels from cosmic rays passing through the substrate, reducing the triggered event rate by a factor of 15 from a previous flight of the instrument.Comment: 14 pages, 7 figures, to be published in Ap