Considerations on a revision of the quality factor

A modified analytical expression is proposed for the revised quality factor that has been suggested by a liaison group of ICRP and ICRU. With this modification one obtains, for sparsely ionizing radiation, a quality factor which is proportional to the dose average of lineal energy, y. It is shown that the proposed relation between the quality factor and lineal energy can be translated into a largely equivalent dependence on LET. The choice between the reference parameters LET or y is therefore a secondary problem in an impending revision of the quality factor

Breast cancer: Monitoring response to neoadjuvant chemotherapy using Tc-99m sestamibi scintimammography

Background: Aim of the study was to assess the value of scintimammography using Tc-99m sestamibi in the evaluation of tumor response to neoadjuvant chemotherapy. Material and Methods: Results were calculated for 9 patients undergoing neoadjuvant chemotherapy. Scintimammography using 740 MBq Tc-99m sestamibi was performed before, during and after chemotherapy, and sestamibi uptake was scored visually and semiquantitatively to evaluate tumor response. Results: In the case of complete response (n = 3) sestamibi uptake decreased 8 days after beginning neoadjuvant chemotherapy and normalized in the following course. Focal uptake decreased more slowly in patients with partial response (n = 3), who showed clear, persisting tracer accumulation after therapy. The patients without response (n = 3) showed a persisting high tumor activity even after chemotherapy was completed. Conclusions: The preliminary data suggest that in contrast to other imaging modalities scintimammography appears to yield early information regarding tumor response to neoadjuvant chemotherapy

Towards retrieving force feedback in robotic-assisted surgery: a supervised neuro-recurrent-vision approach

Robotic-assisted minimally invasive surgeries have gained a lot of popularity over conventional procedures as they offer many benefits to both surgeons and patients. Nonetheless, they still suffer from some limitations that affect their outcome. One of them is the lack of force feedback which restricts the surgeon's sense of touch and might reduce precision during a procedure. To overcome this limitation, we propose a novel force estimation approach that combines a vision based solution with supervised learning to estimate the applied force and provide the surgeon with a suitable representation of it. The proposed solution starts with extracting the geometry of motion of the heart's surface by minimizing an energy functional to recover its 3D deformable structure. A deep network, based on a LSTM-RNN architecture, is then used to learn the relationship between the extracted visual-geometric information and the applied force, and to find accurate mapping between the two. Our proposed force estimation solution avoids the drawbacks usually associated with force sensing devices, such as biocompatibility and integration issues. We evaluate our approach on phantom and realistic tissues in which we report an average root-mean square error of 0.02 N.Peer ReviewedPostprint (author's final draft

Draft genome sequence of the Streptococcus pneumoniae Avery strain A66

We have used HiSeq 2000 technology to generate a draft genome sequence of Streptococcus pneumoniae strain A66. This is a common study strain used in investigations of pneumococcal bacterium-host interactions and was used in the seminal genetic studies of Avery et al

A generalization of heterochromatic graphs

In 2006, Suzuki, and Akbari & Alipour independently presented a necessary and sufficient condition for edge-colored graphs to have a heterochromatic spanning tree, where a heterochromatic spanning tree is a spanning tree whose edges have distinct colors. In this paper, we propose $f$-chromatic graphs as a generalization of heterochromatic graphs. An edge-colored graph is $f$-chromatic if each color $c$ appears on at most $f(c)$ edges. We also present a necessary and sufficient condition for edge-colored graphs to have an $f$-chromatic spanning forest with exactly $m$ components. Moreover, using this criterion, we show that a $g$-chromatic graph $G$ of order $n$ with $|E(G)|>\binom{n-m}{2}$ has an $f$-chromatic spanning forest with exactly $m$ ($1 \le m \le n-1$) components if $g(c) \le \frac{|E(G)|}{n-m}f(c)$ for any color $c$.Comment: 14 pages, 4 figure

Parametric LTL on Markov Chains

This paper is concerned with the verification of finite Markov chains against parametrized LTL (pLTL) formulas. In pLTL, the until-modality is equipped with a bound that contains variables; e.g., $\Diamond_{\le x}\ \varphi$ asserts that $\varphi$ holds within $x$ time steps, where $x$ is a variable on natural numbers. The central problem studied in this paper is to determine the set of parameter valuations $V_{\prec p} (\varphi)$ for which the probability to satisfy pLTL-formula $\varphi$ in a Markov chain meets a given threshold $\prec p$, where $\prec$ is a comparison on reals and $p$ a probability. As for pLTL determining the emptiness of $V_{> 0}(\varphi)$ is undecidable, we consider several logic fragments. We consider parametric reachability properties, a sub-logic of pLTL restricted to next and $\Diamond_{\le x}$, parametric B\"uchi properties and finally, a maximal subclass of pLTL for which emptiness of $V_{> 0}(\varphi)$ is decidable.Comment: TCS Track B 201