Progressive subretinal fibrosis and blindness in patients with multifocal granulomatous chorioretinitis

Since women with a first-degree relative with breast cancer are at increased risk for breast cancer, it is of special importance that they adhere to early detection programs. In this study, women with (389) and without (3295) a family history of breast cancer were compared with respect to risk perception, breast cancer anxiety, and early detection behavior. Special attention was paid to the role of knowing that family history is a breast cancer risk factor. It was found that 46% of "family history positives" did not know that their risk was increased by their family history. Still, family history positives had increased risk perception; our results suggest that this was partly caused by their knowing they belonged to a risk group and partly by their having experienced the disease at close range. Although family history positives had higher risk perceptions, no differences in early detection behavior were found. This could not be attributed to high anxiety levels. Implications for health education are discussed.     

Parametric embedding for class visualization

We propose a new method, parametric embedding (PE), that embeds objects with the class structure into a low-dimensional visualization space. PE takes as input a set of class conditional probabilities for given data points and tries to preserve the structure in an embedding space by minimizing a sum of Kullback-Leibler divergences, under the assumption that samples are generated by a gaussian mixture with equal covariances in the embedding space. PE has many potential uses depending on the source of the input data, providing insight into the classifier's behavior in supervised, semisupervised, and unsupervised settings. The PE algorithm has a computational advantage over conventional embedding methods based on pairwise object relations since its complexity scales with the product of the number of objects and the number of classes. We demonstrate PE by visualizing supervised categorization of Web pages, semisupervised categorization of digits, and the relations of words and latent topics found by an unsupervised algorithm, latent Dirichlet allocation.     

Evidence for transient composition variations at GaAs/Ga1−xAlxAs heterostructure interfaces prepared by metal-organic chemical vapour deposition

The composition profiles of GaAs/Ga_1?xAl_xAs heterostructures prepared in two different Metal-Organic Chemical Vapour Deposition (MOCVD) reactors have been studied. Transmission electron microscopy (TEM). and Auger and secondary ion mass spectrometry (SIMS) sputter profiling results are in good agreement and interface widths below 20 å have been achieved. Significant new results on transient phenomena have been obtained. showing that large and sometimes very sharp excursions in composition can be associated with valve switching actions. Direct evidence is presented that gas pressure or flow transients can occur during valve operations. and it is suggested that such instabilities are the cause of the effects observed.     

The renal factor in the post-traumatic "fluid overload" syndrome

Hypervolemia with hypertension often occurs 36-72 hours following massive blood and fluid replacement for hypovolemic shock. This syndrome of "fluid overload" has been attributed to the rapid intravascular flux of previously sequestered fluid in patients with impaired diuresis. This hypothesis was tested in 35 injured patients who received a mean of 9.3 L of blood and 17.4 L of salt during resucitation. The renal parameters measured soon after resuscitation included: 1) renal clearance of inulin (GFR), para-amino hippurate (ERPF), milliosmoles, sodium, and free water; 2) inulin space, renal vascular resistance (RVR), O2 consumption, renin, renal blood flow (RBF), and response to furosemide. Eighteen patients developed hypertension, hypervolemia, and respiratory insufficiency. When compared to the 17 normovolemic, non-hypertensive patients, the 18 hypervolemic patients had significantly increased RVR, with a significant decrease in RBF despite an increase in plasma volume and cardiac output. Furosemide produced less diuresis and natriuresis in the hypertensive patients. The balance between hypovolemia and "fluid overload" seemed percarious in the hypertensive patients. Peripheral renin and catecholamine levels were normal in both groups. Patients with post-traumatic "fluid overload" appear to have a combination of hypervolemia, respiratory insufficiency, hypertension, increased cardiac output, decreased extracellular fluid space, and decreased renal perfusion. These findings suggest that decreased interstitial fluid space compliance rather than "fluid overload" is the underlying factor leading to respiratory insufficiency. The therapeutic aspects of these findings are discussed.     

Psychosomatic disease and the problem of causation

Despite its impressive rate of growth in the past decades, an increasing amount if dissatisfaction with the area of psychosomatic medicine is reflected in recent literature. The discipline's failures relate to concepts of pathogenesis and therapeutic application of research findings. These failures are explained as a necessary consequence of the philosophical tenet of mind-body dualism which underlies medical theory. It is urged that advocates of psychosomatic medicine give the concept of "holism" meaning at the most fundamental level by establishing a rational basis for theory, or else forsake this line of research for others which yield causal relationships conductive to effective therapy.     

Tandem mass spectrometry in the study of fatty acids,bile acids,and steroids

Over the last 50 years, the mass spectrometry of lipids has evolved to become one of the most mature techniques in biomolecule analysis. Many volatile and non-polar lipids are directly amenable to analysis by gas-chromatography-mass spectrometry (GC-MS), a technique that combines the unsurpassed separation properties of gas-chromatography with the sensitivity and selectivity of electron ionization mass spectrometry. Less volatile and/or thermally labile lipids can be analyzed by GC-MS, following appropriate sample derivatization. However, many complex lipids are not readily analyzed by GC-MS, and it is these molecules that are the subject of the current review. Since the early 1970s, there have been three outstanding developments in mass spectrometry that are particularly appropriate in lipid analysis; i.e., the introduction of (i) fast atom bombardment (FAB); (ii) electrospray (ES); and (iii) tandem mass spectrometry (MS/MS). The FAB and ES ionization techniques will be discussed in relation to MS/MS, and examples of their application in biochemical studies will be presented. The review will concentrate on the analysis of fatty acids, bile acids, steroid conjugates, and neutral steroids.     

Design principles for preschool children’s interactive TV

Preschool children have increased access to media via a number of platforms, including digital interactive television. However, the viewing and interaction needs of this user group have not been extensively researched. The project reported in this paper investigates preschoolers’ interactions with a simulated interactive television set-up. The study involved the development of an electronic programme guide prototype and its empirical evaluation. This research was carried out with children in Brazil and in the United Kingdom, aged between three and four. The main issues that arose during the interaction with the prototype application are documented, and a list of design principles is presented to assist in the design of accessible preschool interactive television applications for this age group.     

Prevalence and Characteristics of Game Transfer Phenomena: A Descriptive Survey Study

Previous qualitative studies suggest that gamers experience Game Transfer Phenomena (GTP), a variety of non-volitional phenomena related to playing videogames including thoughts, urges, images, and sounds when not playing. To investigate (i) which types of GTP were more common and (ii) their general characteristics, the present study surveyed a total of 2362 gamers via an online survey. The majority of the participants were male, students, aged between 18 and 27 years, and “hard-core” gamers. Most participants reported having experienced at least one type of GTP at some point (96.6%), the majority having experienced GTP more than once, with many reporting 6 to 10 different types of GTP. Results demonstrated that videogame players experienced (i) altered visual perceptions, (ii) altered auditory perceptions, (iii) altered body perceptions, (iv) automated mental processes, and (v) behaviors. In most cases, GTP could not be explained by being under the influence of a psychoactive substance. The GTP experiences were usually short-lived, tended to occur after videogame playing rather than during play, occurred recurrently, and usually occurred while doing day-to-day activities. One in five gamers had experienced some type of distress or dysfunction due to GTP. Many experienced GTP as pleasant and some wanted GTP to happen again.