8,982 research outputs found
Feasibility of Photofrin II as a radiosensitizing agent in solid tumors - Preliminary results
Background: Photofrin II has been demonstrated to serve as a specific and selective radiosensitizing agent in in vitro and in vivo tumor models. We aimed to investigate the feasibility of a clinical application of Photofrin II. Material and Methods: 12 patients were included in the study (7 unresectable solid tumors of the pelvic region, 3 malignant gliomas, 1 recurrent oropharyngeal cancer, 1 recurrent adenocarcinoma of the sphenoid sinus). The dose of ionizing irradiation was 30-50.4 Gy; a boost irradiation of 14 Gy was added for the pelvic region. All patients were intravenously injected with 1 mg/kg Photofrin II 24 h prior to the commencement of radiotherapy. Magnetic resonance imaging (MRI) controls and in some cases positron emission tomography (PET) were performed in short intervals. The mean follow-up was 12.9 months. Results: No major adverse events were noted. Minor adverse events consisted of mild diarrhea, nausea and skin reactions. A complete remission was observed in 4/12 patients. A reduction in local tumor volume of > 45% was achieved in 4/12 patients. Stable disease was observed in 4/12 patients. 1 patient showed local disease progression after 5 months. Conclusion: The early follow-up results are encouraging regarding the feasibility of the application of Photofrin II as a radiosensitizing agent
Atom gravimeters and gravitational redshift
In a recent paper, H. Mueller, A. Peters and S. Chu [A precision measurement
of the gravitational redshift by the interference of matter waves, Nature 463,
926-929 (2010)] argued that atom interferometry experiments published a decade
ago did in fact measure the gravitational redshift on the quantum clock
operating at the very high Compton frequency associated with the rest mass of
the Caesium atom. In the present Communication we show that this interpretation
is incorrect.Comment: 2 pages, Brief Communication appeared in Nature (2 September 2010
Self-Affirmation Improves Problem-Solving under Stress
High levels of acute and chronic stress are known to impair problem-solving and creativity on a broad range of tasks. Despite this evidence, we know little about protective factors for mitigating the deleterious effects of stress on problem-solving. Building on previous research showing that self-affirmation can buffer stress, we tested whether an experimental manipulation of self-affirmation improves problem-solving performance in chronically stressed participants. Eighty undergraduates indicated their perceived chronic stress over the previous month and were randomly assigned to either a self-affirmation or control condition. They then completed 30 difficult remote associate problem-solving items under time pressure in front of an evaluator. Results showed that self-affirmation improved problem-solving performance in underperforming chronically stressed individuals. This research suggests a novel means for boosting problem-solving under stress and may have important implications for understanding how self-affirmation boosts academic achievement in school settings. © 2013 Creswell et al
The Off-Shell Electromagnetic T-matrix: momentum-dependent scattering from spherical inclusions with both dielectric and magnetic contrast
The momentum- and frequency-dependent T-matrix operator for the scattering of
electromagnetic waves by a dielectric/conducting and para- or diamagnetic
sphere is derived as a Mie-type series, and presented in a compact form
emphasizing various symmetry properties, notably the unitarity identity. This
result extends to magnetic properties one previously obtained for purely
dielectric contrasts by other authors. Several situations useful to
spatially-dispersive effective-medium approximations to one-body order are
examined. Partial summation of the Mie series is achieved in the case of
elastic scattering.Comment: 22 pages. Preprint of a paper to appear in `Waves in Complex And
Random Media' ((c) Taylor and Francis, 2011
Automorphisms of graphs of cyclic splittings of free groups
We prove that any isometry of the graph of cyclic splittings of a finitely
generated free group of rank is induced by an outer automorphism
of . The same statement also applies to the graphs of maximally-cyclic
splittings, and of very small splittings.Comment: 22 pages, 5 figures. Small modifications. To appear in Geometriae
Dedicat
Rivaroxaban in antiphospholipid syndrome (RAPS) protocol: a prospective, randomized controlled phase II/III clinical trial of rivaroxaban versus warfarin in patients with thrombotic antiphospholipid syndrome, with or without SLE
Introduction: The current mainstay of the treatment of thrombotic antiphospholipid syndrome
(APS) is long-term anticoagulation with vitamin K antagonists (VKAs) such as warfarin.
Non-VKA oral anticoagulants (NOACs), which include rivaroxaban, have been shown to
be effective and safe compared with warfarin for the treatment of venous thromboembolism
(VTE) in major phase III prospective, randomized controlled trials (RCTs), but the results
may not be directly generalizable to patients with APS. Aims: The primary aim is to demonstrate,
in patients with APS and previous VTE, with or without systemic lupus erythematosus
(SLE), that the intensity of anticoagulation achieved with rivaroxaban is not inferior to that of
warfarin. Secondary aims are to compare rates of recurrent thrombosis, bleeding and the
quality of life in patients on rivaroxaban with those on warfarin. Methods: Rivaroxaban in
antiphospholipid syndrome (RAPS) is a phase II/III prospective non-inferiority RCT in which
eligible patients with APS, with or without SLE, who are on warfarin, target international
normalized ratio (INR) 2.5 for previous VTE, will be randomized either to continue warfarin
(standard of care) or to switch to rivaroxaban. Intensity of anticoagulation will be assessed
using thrombin generation (TG) testing, with the primary outcome the percentage change in
endogenous thrombin potential (ETP) from randomization to day 42. Other TG parameters,
markers of in vivo coagulation activation, prothrombin fragment 1.2, thrombin antithrombin
complex and D-dimer, will also be assessed. Discussion: If RAPS demonstrates i) that the
anticoagulant effect of rivaroxaban is not inferior to that of warfarin and ii) the absence of any
adverse effects that cause concern with regard to the use of rivaroxaban, this would provide
sufficient supporting evidence to make rivaroxaban a standard of care for the treatment of
APS patients with previous VTE, requiring a target INR of 2.5
Making Code Voting Secure against Insider Threats using Unconditionally Secure MIX Schemes and Human PSMT Protocols
Code voting was introduced by Chaum as a solution for using a possibly
infected-by-malware device to cast a vote in an electronic voting application.
Chaum's work on code voting assumed voting codes are physically delivered to
voters using the mail system, implicitly requiring to trust the mail system.
This is not necessarily a valid assumption to make - especially if the mail
system cannot be trusted. When conspiring with the recipient of the cast
ballots, privacy is broken.
It is clear to the public that when it comes to privacy, computers and
"secure" communication over the Internet cannot fully be trusted. This
emphasizes the importance of using: (1) Unconditional security for secure
network communication. (2) Reduce reliance on untrusted computers.
In this paper we explore how to remove the mail system trust assumption in
code voting. We use PSMT protocols (SCN 2012) where with the help of visual
aids, humans can carry out addition correctly with a 99\% degree of
accuracy. We introduce an unconditionally secure MIX based on the combinatorics
of set systems.
Given that end users of our proposed voting scheme construction are humans we
\emph{cannot use} classical Secure Multi Party Computation protocols.
Our solutions are for both single and multi-seat elections achieving:
\begin{enumerate}[i)]
\item An anonymous and perfectly secure communication network secure against
a -bounded passive adversary used to deliver voting,
\item The end step of the protocol can be handled by a human to evade the
threat of malware. \end{enumerate} We do not focus on active adversaries
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A behavioral comparison of male and female adults with high functioning autism spectrum conditions
Autism spectrum conditions (ASC) affect more males than females in the general population. However, within ASC it is unclear if there are phenotypic sex differences. Testing for similarities and differences between the sexes is important not only for clinical assessment but also has implications for theories of typical sex differences and of autism. Using cognitive and behavioral measures, we investigated similarities and differences between the sexes in age- and IQ-matched adults with ASC (high-functioning autism or Asperger syndrome). Of the 83 (45 males and 38 females) participants, 62 (33 males and 29 females) met Autism Diagnostic Interview-Revised (ADI-R) cut-off criteria for autism in childhood and were included in all subsequent analyses. The severity of childhood core autism symptoms did not differ between the sexes. Males and females also did not differ in self-reported empathy, systemizing, anxiety, depression, and obsessive-compulsive traits/symptoms or mentalizing performance. However, adult females with ASC showed more lifetime sensory symptoms (p = 0.036), fewer current socio-communication difficulties (p = 0.001), and more self-reported autistic traits (p = 0.012) than males. In addition, females with ASC who also had developmental language delay had lower current performance IQ than those without developmental language delay (p<0.001), a pattern not seen in males. The absence of typical sex differences in empathizing-systemizing profiles within the autism spectrum confirms a prediction from the extreme male brain theory. Behavioral sex differences within ASC may also reflect different developmental mechanisms between males and females with ASC. We discuss the importance of the superficially better socio-communication ability in adult females with ASC in terms of why females with ASC may more often go under-recognized, and receive their diagnosis later, than males
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