549 research outputs found
The gift of the code: A culture of an operating system
“The Gift of the Code” explores the boundaries between technology and sociality, computers and cultures. Based on long-term ethnographic research among users and developers of GNU/Linux Operating System, this work analyses how Linux developers and users consume, create and exchange an as much technical as cultural discursive construction of sociality. Like a modern-day kula ring, the Linux code is analysed in terms of a gift: one cannot keep it for one’s self, it contains obligations and a promise of future reciprocity. It is a collective gift of the self-ascribed Hackers that come from different geographic places and meet in lines of code, socializing by exchanging ideas about the code and about themselves. This work shows by what means the computer hackers of Linux, abiding to the original definition of the word, actively constitute their community using discourse: language, e-mail, internal meritocratic hierarchies based on technical ability and ethics of the group, boundaries of exclusion and inclusion. This project is about power relations, resistance networks and the hegemony of a techno-scientific self-indulgence of some post-residents of an imagined cyber-West. Equally, it is about the giving of gifts, hacker culture and the ‘fun’ of hacking, creating and maintaining a ‘guerrilla’ operating system. Studying the anthropology of GNU/Linux operating system is a journey towards an investigation of what makes the social into technology and how technology is translated into sociality
PFAPA syndrome: a review on treatment and outcome.
The syndrome of periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA syndrome) is the most common cause of periodic fever in childhood. The current pharmacological treatment includes corticosteroids, which usually are efficacious in the management of fever episodes, colchicine, for the prophylaxis of febrile episodes, and other medication for which efficacy has not been proven so far. Tonsillectomy is an option for selected patients. Usually PFAPA syndrome resolves during adolescence, but there is increasing evidence that this condition may persist into adulthood
CRITERION, CONSTRUCT AND FACTORIAL VALIDITY OF THE GREEK VERSION OF THE INTERNATIONAL PHYSICAL ACTIVITY QUESTIONNAIRE-SHORT FORM (IPAQ-SF)
The current study investigated the validity of the Greek version of the International Physical Activity Questionnaire-short form (IPAQ-SF, seven days recall period, Craig et al., 2003). Specifically, criterion and construct validity were examined in a sample of 120 adults (M ± SD = 30.52 ± 14.87 years). In addition, factorial validity and internal consistency were examined in a second sample of 726 physically active adults (M ± SD = 38.80 ± 13.64 years). Further, associations were examined among the IPAQ-SF, exercise self-efficacy, body mass index and various socio-demographic variables. The statistical analyses indicated: (a) acceptable validity coefficients and factorial validity of the IPAQ, (b) acceptable internal consistency, (c) higher physical activity values in men compared to women and in athletes compared to non-athletes, (d) positive correlations between physical activity levels, exercise self-efficacy and past physical activity and (e) negative correlations among physical activity, age, number of children and body mass index. The Greek version of the IPAQ-SF was valid and therefore, could be useful for assessing physical activity. Article visualizations
Sensitivity of Ag/Al Interface Specific Resistances to Interfacial Intermixing
We have measured an Ag/Al interface specific resistance, 2AR(Ag/Al)(111) =
1.4 fOhm-m^2, that is twice that predicted for a perfect interface, 50% larger
than for a 2 ML 50%-50% alloy, and even larger than our newly predicted 1.3
fOhmm^2 for a 4 ML 50%-50% alloy. Such a large value of 2ARAg/Al(111) confirms
a predicted sensitivity to interfacial disorder and suggests an interface
greater than or equal to 4 ML thick. From our calculations, a predicted
anisotropy ratio, 2AR(Ag/Al)(001)/2AR(Ag/Al)(111), of more then 4 for a perfect
interface, should be reduced to less than 2 for a 4 ML interface, making it
harder to detect any such anisotropy.Comment: 3 pages, 2 figures, 1 table. In Press: Journal of Applied Physic
Comparison of Measured and Calculated Specific Resistances of Pd/Pt Interfaces
We compare specific resistances (AR equals area A times resistance R) of
sputtered Pd/Pt interfaces measured in two different ways with
no-free-parameter calculations. One way gives 2AR(Pd/Pt) of 0.29 (0.03)
fohm-m(2) and the other 0.17 (0.13) fohm-m(2). From these we derive a best
estimate of 2AR(Pd/Pt) of 0.28 (0.06) fohm-m(2), which overlaps with
no-free-parameter calculations: 2AR(predicted) of 0.30 (0.04) fohm-m(2) for
flat, perfect interfaces, or 0.33 (0.04) fohm-m(2) for interfaces composed of 2
monolayers of a 50percent-50percent PdPt alloy. These results support three
prior examples of agreement between calculations and measurements for pairs of
metals having the same crystal structure and the same lattice parameter to
within 1 percent. We also estimate the spin-flipping probability at Pd/Pt
interfaces as 0.13 (0.08).Comment: 3 pages, 3 figures, submitted for publication New version has
corrected value of delta(Pd/Pt
A case of corticosteroid-dependent recurrent pericarditis with different response to two IL-1 blocking agents
Background: Recurrent pericarditis (RP) represents the most troublesome presentation of pericarditis and has a controversial pathogenesis that crosses infectious, auto-immune and auto-inflammatory pathways. It has been suggested that in some cases it might be an unrecognized auto-inflammatory disease. Recent studies have demonstrated that anakinra, an interleukin-1 receptor antagonist (IL-1RA), represents an effective treatment for the control of corticosteroid-dependent cases.
Objectives: To describe a case of cortico-dependent recurrent pericarditis with a different response to two IL-1 blocking agents, anakinra and canakinumab.
Methods: Case report
Results: 11 years old boy who was admitted to our hospital because of acute precordial pain, orthopnea, fever and increased levels of acute phase reactants. Acute pericarditis was confirmed by echocardiography and a treatment with prednisone was started with prompt clinical improvement. Pericarditis recurred twice during steroid tapering (1mg/kg/day and 0.5mg/kg/day respectively). After exclusion of infectious origin, therapy with anakinra (2mg/kg/day) was established (to avoid long term steroid side effects) followed by dramatic clinical response and normalisation of laboratory findings despite tapering and discontinuation of prednisone. Treatment with anakinra was discontinued after 5 months with recurrence of pericarditis one week later. Anakinra was resumed with an excellent response. Five months later, while being in complete remission, anakinra was replaced with canakinumab (2mg/kg/dose) due to patient’s intolerance of daily injections. One week later, the patient experienced a new episode of pericarditis requiring corticotherapy. Two more relapses occured during steroid tapering, after 6 weeks and 2 months, in spite of the uptitration of canakinumab to 4mg/kg/dose. Anakinra was restarted with prompt clinical and biological remission and prednisone was discontinuated without recurrence of pericarditis. After further four weeks follow-up under anakinra alone, the pericarditis is still in remission.
Conclusion: We describe a case of steroid-dependent RP with a dramatic therapeutic response to IL-1RA (anakinra) but without response to IL-1β monoclonal antibody (canakinumab). This unexpected observation could suggest that Il-1α might have a role in the pathogenesis of RP. The definitive potential usefulness of each IL-1 blocking agent requires confirmation in prospective controlled trials
Coexistence of glassy antiferromagnetism and giant magnetoresistance (GMR) in Fe/Cr multilayer structures
Using temperature-dependent magnetoresistance and magnetization measurements
on Fe/Cr multilayers that exhibit pronounced giant magnetoresistance (GMR), we
have found evidence for the presence of a glassy antiferromagnetic (GAF) phase.
This phase reflects the influence of interlayer exchange coupling (IEC) at low
temperature (T < 140K) and is characterized by a field-independent glassy
transition temperature, Tg, together with irreversible behavior having
logarithmic time dependence below a "de Almeida and Thouless" (AT) critical
field line. At room temperature, where the GMR effect is still robust, IEC
plays only a minor role, and it is the random potential variations acting on
the magnetic domains that are responsible for the antiparallel interlayer
domain alignment.Comment: 5 pages, 4 figure
- …