Analysis of MySpace user profiles

Online social networks have attracted millions of users, who have integrated social network web sites into their daily life. Users participate to the changes and to the evolution of these sites because they are producers and reviewers of contents that help them to maintain the existing social relationships, make new friends, collaborate and enrich experiences. This paper presents a study of the characteristics of the users of MySpace web site, with the objective of studying relationships and interactions among users and deriving hints about their behavior. The analysis relies on data collected by monitoring the web site for 12 weeks. Typical user behaviors have been derived and classes of users characterized by different levels of participation to the social network have been identified. In particular, the analysis reveals that most of the users actively participate to the social network and specify many personal details. Social networks web sites allow access to such details; the sharing of information about users and their relationships can lead to non-ethic online activities, which threat the privacy and the security of users themselves.     

Imaging size-selective permeation through micropatterned thin films using scanning electrochemical microscopy

This paper describes a new approach for quantification of rates of molecular transport through patterned, or otherwise heterogeneous, porous films supported on conductive substrates. Scanning Electrochemical Microscopy (SECM) has been used to image molecular sieving of redox active probes by thin, electropolymerized films of Fe(5-amino-1,10-phenanthroline)3(2+) on micropatterned and microdisk array electrodes. Films as thin as 12 nm completely block redox mediators with average molecular diameters greater than 12 A, whereas smaller diameter probes (radii 5-8 A) were observed to permeate selectively. SECM tip currents measured for three different redox permeants/mediators are observed to decrease with increasing polymer thickness, consistent with a transport model that includes partitioning into and diffusion within the polymer films. Permeabilities, PDf, within the poly[Fe(5-NH2-phen)3(2+)] films have been quantitatively determined from the SECM tip currents and are in excellent agreement with data previously obtained from rotatingdisk electrochemistry. This new methodology provides a versatile approach for quantitative investigation of membrane transport and permeation selectivity with good lateral spatial resolution.     

Charge-mixer based on MOS interface-trap charge pump

A 3.3 V charge-mixer device in a 0.35 /spl mu/m CMOS process detects the intensity and phase of a modulated signal. A two PMOS pair is used as charge-mixer to exploit the interface-trap charge pump phenomenon. Using clocking between accumulation and inversion, the two transistors perform a voltage-to-charge conversion of the input signal and transfer this charge to the two outputs synchronously to the applied signal.     

First observation of intersex cyprinids in the Po River (Italy)

Barbel (Barbus plebejus, Cyprinidae) were captured in the Po River, upstream and downstream from the confluence of the Lambro River, a polluted tributary of the major Italian watercourse. The gonads of the two groups of barbel have been histologically examined, and only the downstream specimens showed histo-morphological alterations that can be related to the Lambro tributary as a source to the main river of endocrine disrupting chemicals, possibly with estrogenic effects. In fact, 50% of the barbel captured (8 of 16 fish) in the downstream reach showed intersex gonads.     

Low power WTA circuit for optical position detector

A time domain winner take all (WTA) circuit for a 1D optical position detector is presented. The circuit implements a new asynchronous technique which estimates the position of a light spot impinging on the sensor with sub-pixel resolution. This technique first detects the peak of the light spot, then, starts a new competition, by eliminating the winner pixel. In this way the sensor asynchronously dispatches the pixels in order to reconstruct the spot profile. The simulated circuit shows a total power consumption of about 15.6 muW at 3.3 V, while the average dynamic power consumption needed to implement one step of the algorithm, can be estimated to be about 0.4 nW     

Comparison between noninvasive indices of baroreceptor sensitivity and the phenylephrine method in post-myocardial infarction patients

BACKGROUND: Depressed baroreflex sensitivity obtained by means of a phenylephrine test plays a prognostic role in patients with a previous myocardial infarction. Our purpose was to evaluate the correlation and agreement between the baroreflex sensitivity obtained with phenylephrine and that obtained by two noninvasive methods: the alpha-index and sequence analysis. METHODS AND RESULTS: The alpha-index was measured by means of the spectral analysis of RR and systolic blood pressure variabilities in both the high- and low-frequency bands; sequences were identified from simultaneously recorded time series in which the RR and systolic blood pressure concurrently increased or decreased. Noninvasive baroreflex sensitivity tests were performed during both spontaneous and controlled respiration. Fifty-two consecutive patients with recent myocardial infarction underwent the analyses. Although the correlations between phenylephrine and either of the noninvasive methods were always significant, those found during controlled respiration had the highest r values (r=.70). However, the limits of agreement calculated by means of the Bland and Altman method were wide for both noninvasive methods. CONCLUSIONS: The results obtained by means of noninvasive baroreflex sensitivity assessments should not be used in clinical practice as an alternative to those obtained by the phenylephrine method.     

Wartime military service and utilization of VA health care services

A case of an atypical thyroglossal duct cyst is described in a 9-year-old boy who presented with a lateral neck mass that was hypofunctioning on thyroid scan and clinically indistinguishable from a thyroid nodule. Preoperative fine needle aspiration biopsy results demonstrating abundant, normal appearing squamous epithelial cells and keratinaceous material was suggestive of the diagnosis. Definitive diagnosis was made only after complete mobilization of the left lobe of the thyroid gland and cyst resection. A standard Sistrunk procedure was performed, and cyst excision was accomplished without resection of the left lobe of the thyroid gland. Microscopic examination disclosed a keratinizing pseudostratified squamous epithelium that has not been previously reported with thyroglossal duct cysts.     

Effect of 2 types of diet changes on dietary habits, body weight and cholesterol levels in high risk cardiovascular patients

Several non-pharmacological interventions such as weight reduction in obese subjects or diet alteration in subjects having hypercholesterolemia have been shown to be effective in therapeutic trials. Our aim was to test the value of two different ways of teaching patients about their diet. From March 1, 1993, to May 30, 1994, 300 consecutive patients seen in a one-day care hospital were randomised into two groups. The 2 inclusion criteria were: 1) body mass index > 27 kg/m2 in men and > to 25 kg/m2 in women and/or 2) presence of a hypercholesterolemia defined by a total cholesterol > 6.5 mmol/l. Patients in the first group (C) were educated in a 20 to 50 minutes consultation tailored to their needs. Patients in the second group (CC) were given in addition a one-hour course about diet. The goal of the diet was to loss at least 3 kg of body weight and/or to have a cholesterol value below 6.5 mmol/l without treatment. All Patients were followed-up by the same 3 dietician nurses. An out-patient visit was planned at 3 months, and a recall letter was sent to the patients who missed their appointments. Among the 300 patients, 169 (55%) were seen at the 3-month outpatient visit. This proportion did not differ between the 2 groups. Knowledge on diet was assessed by the same 33-item self-administered questionnaire. At baseline scores were comparable between groups (16 vs 17). Scores improved more in the CC than in the C group both at the end of the teaching question (27 vs 23 in the CC and C group respectively, p < 0.001), and at 3 months (25 vs 23 in the CC and C group respectively; p < 0.001). Total cholesterol decreased below 6.5 mmol/l in 28% of the patients with dyslipidemia and a weight loss > 3 kg was observed in 32% of the obese subjects, but improvement did not differ between the 2 groups. We conclude that a specific one-hour course on diet is able to improve knowledge of patients more than a consultation alone, but that better knowledge did not result in improved alteration of risk factors at 3 months.     

Linking Hydro-Physical Variables and Landscape Metrics using Advanced Data Mining for Stream-Flow Prediction

Water Resources Management - In Streamflow prediction the most important triggering/controlling variables are related to climate, physiography, and landscape patterns. This study investigated the...