327 research outputs found
Comparison of X-ray and gamma-ray dose-response curves for pink somatic mutations in Tradescantia clone 02
Microdosimetric data indicate that the mean specific energy,zeta, produced by individual charged particles from X rays and gamma rays is different for the two radiation qualities by nearly a factor of two. In order to test whether this influences the initial, linear component in the dose-effect relations, a comparison was made between dose-response curves for pink somatic mutations inTradescantia clone 02 stamen hairs following X and gamma irradiations. Absorbed doses ranged from 2.66 to 300 rad. The results are in agreement with predictions made on the basis of microdosimetric data. At low doses gamma rays are substantially less effective than X rays. The RBE of gamma rays vs. X rays at low doses was approximately 0.6, a value lower than those usually reported in other experimental systems
Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge
Using a novel electrochemical phase-field model, we question the common
belief that LixFePO4 nanoparticles separate into Li-rich and Li-poor phases
during battery discharge. For small currents, spinodal decomposition or
nucleation leads to moving phase boundaries. Above a critical current density
(in the Tafel regime), the spinodal disappears, and particles fill
homogeneously, which may explain the superior rate capability and long cycle
life of nano-LiFePO4 cathodes.Comment: 27 pages, 8 figure
Scintillator counters with WLS fiber/MPPC readout for the side muon range detector (SMRD)of the T2K experiment
The T2K neutrino experiment at J-PARC uses a set of near detectors to measure
the properties of an unoscillated neutrino beam and neutrino interaction
cross-sections. One of the sub-detectors of the near-detector complex, the side
muon range detector (SMRD), is described in the paper. The detector is designed
to help measure the neutrino energy spectrum, to identify background and to
calibrate the other detectors. The active elements of the SMRD consist of 0.7
cm thick extruded scintillator slabs inserted into air gaps of the UA1 magnet
yokes. The readout of each scintillator slab is provided through a single WLS
fiber embedded into a serpentine shaped groove. Two Hamamatsu multi-pixel
avalanche photodiodes (MPPC's) are coupled to both ends of the WLS fiber. This
design allows us to achieve a high MIP detection efficiency of greater than
99%. A light yield of 25-50 p.e./MIP, a time resolution of about 1 ns and a
spatial resolution along the slab better than 10 cm were obtained for the SMRD
counters.Comment: 7 pages, 4 figures; talk at TIPP09, March 12-17, Tsukuba, Japan; to
be published in the conference proceeding
The T2K Side Muon Range Detector
The T2K experiment is a long baseline neutrino oscillation experiment aiming
to observe the appearance of {\nu} e in a {\nu}{\mu} beam. The {\nu}{\mu} beam
is produced at the Japan Proton Accelerator Research Complex (J-PARC), observed
with the 295 km distant Super- Kamiokande Detector and monitored by a suite of
near detectors at 280m from the proton target. The near detectors include a
magnetized off-axis detector (ND280) which measures the un-oscillated neutrino
flux and neutrino cross sections. The present paper describes the outermost
component of ND280 which is a side muon range detector (SMRD) composed of
scintillation counters with embedded wavelength shifting fibers and Multi-Pixel
Photon Counter read-out. The components, performance and response of the SMRD
are presented.Comment: 13 pages, 19 figures v2: fixed several typos; fixed reference
A P2P Botnet detection scheme based on decision tree and adaptive multilayer neural networks
In recent years, Botnets have been adopted as a popular method to carry and spread many malicious codes on the Internet. These malicious codes pave the way to execute many fraudulent activities including spam mail, distributed denial-of-service attacks and click fraud. While many Botnets are set up using centralized communication architecture, the peer-to-peer (P2P) Botnets can adopt a decentralized architecture using an overlay network for exchanging command and control data making their detection even more difficult. This work presents a method of P2P Bot detection based on an adaptive multilayer feed-forward neural network in cooperation with decision trees. A classification and regression tree is applied as a feature selection technique to select relevant features. With these features, a multilayer feed-forward neural network training model is created using a resilient back-propagation learning algorithm. A comparison of feature set selection based on the decision tree, principal component analysis and the ReliefF algorithm indicated that the neural network model with features selection based on decision tree has a better identification accuracy along with lower rates of false positives. The usefulness of the proposed approach is demonstrated by conducting experiments on real network traffic datasets. In these experiments, an average detection rate of 99.08 % with false positive rate of 0.75 % was observed
Theory of Chemical Kinetics and Charge Transfer based on Nonequilibrium Thermodynamics
Classical theories of chemical kinetics assume independent reactions in
dilute solutions, whose rates are determined by mean concentrations. In
condensed matter, strong interactions alter chemical activities and create
inhomogeneities that can dramatically affect the reaction rate. The extreme
case is that of a reaction coupled to a phase transformation, whose kinetics
must depend on the order parameter -- and its gradients, at phase boundaries.
This Account presents a general theory of chemical kinetics based on
nonequilibrium thermodynamics. The reaction rate is a nonlinear function of the
thermodynamic driving force (free energy of reaction) expressed in terms of
variational chemical potentials. The Cahn-Hilliard and Allen-Cahn equations are
unified and extended via a master equation for non-equilibrium chemical
thermodynamics. For electrochemistry, both Marcus and Butler-Volmer kinetics
are generalized for concentrated solutions and ionic solids. The theory is
applied to intercalation dynamics in the phase separating Li-ion battery
material LiFePO.Comment: research account, 17 two-column pages, 12 figs, 78 refs - some typos
corrected Accounts of Chemical Research (2013
Diagnosis and Therapy of Female Pelvic Organ Prolapse. Guideline of the DGGG, SGGG and OEGGG (S2e-Level, AWMF Registry Number 015/006, April 2016).
Aims: The aim was to establish an official interdisciplinary guideline, published and coordinated by the German Society of Gynecology and Obstetrics (DGGG). The guideline was developed for use in German-speaking countries. In addition to the Germany Society of Gynecology and Obstetrics, the guideline has also been approved by the Swiss Society of Gynecology and Obstetrics (SGGG) and the Austrian Society of Gynecology and Obstetrics (OEGGG). This is a guideline published and coordinated by the DGGG. The aim is to provide evidence-based recommendations obtained by evaluating the relevant literature for the diagnostic, conservative and surgical treatment of women with female pelvic organ prolapse with or without stress incontinence. Methods: We conducted a systematic review together with a synthesis of data and meta-analyses, where feasible. MEDLINE, Embase, Cinahl, Pedro and the Cochrane Register were searched for relevant articles. Reference lists were hand-searched, as were the abstracts of the Annual Meetings of the International Continence Society and the International Urogynecological Association. We included only abstracts of randomized controlled trials that were presented and discussed in podium sessions. We assessed original data on surgical procedures published since 2008 with a minimum follow-up time of at least 12 months. If the studies included descriptions of perioperative complications, this minimum follow-up period did not apply. Recommendations: The guideline encompasses recommendations for the diagnosis and treatment of female pelvic organ prolapse. Recommendations for anterior, posterior and apical pelvic organ prolapse with or without concomitant stress urinary incontinence, uterine preservation options, and the pros and cons of mesh placements during surgery for pelvic organ prolapse are presented. The recommendations are based on an extensive and systematic review and evaluation of the current literature and include the experiences and specific conditions in Germany, Austria and Switzerland
The SMRD subdetector at the T2K near detector station
The T2K long-baseline neutrino oscillation experiment is running in Japan. The primary goals of the T2K are measurement of the mixing angle 13, and precise measurements of the mixing angle 23 and of the mass difference m2 23. The installation of the near detector complex was completed and first data were already registered. This article presents operation of the Side Muon Range Detector, a component of the Off-Axis near detector. Detector concept and implementation are presented, followed by a description of cosmic muon track reconstruction algorithm and finally current status
Postępowanie w chorobach tarczycy u kobiet w ciąży
The management of thyroid disorders during pregnancy is one of the most frequently disputed problems in modern endocrinology. It is
widely known that thyroid dysfunction may result in subfertility, and, if inadequately treated during pregnancy, may cause obstetrical
complications and influence fetal development.
The 2007 Endocrine Society Practice Guideline endorsed with the participation of the Latino America Thyroid Association, the American
Thyroid Association, the Asia and Oceania Thyroid Association and the European Thyroid Association, greatly contributed towards uniformity
of the management of thyroid disorders during pregnancy and postpartum. Despite the tremendous progress in knowledge on
the mutual influence of pregnancy and thyroid in health and disease, there are still important areas of uncertainty. There have been at
least a few important studies published in the last 3 years, which influenced the thyroidal care of the expecting mother. It should also be
remembered that guidelines may not always be universally applied in all populations with different ethnical, socio-economical, nutritional
(including iodine intake) background or exposed to different iodine prophylaxis models.
The Task Force for development of guidelines for thyroid dysfunction management in pregnant women was established in 2008. The expert
group has recognized the following tasks: development of the coherent model of the management of thyroid dysfunction in pregnant
women, identification of the group of women at risk of thyroid dysfunction, who may require endocrine care in the preconception period,
during pregnancy and postpartum – that is in other words, the development of Polish recommendations for targeted thyroid disorder case
finding during pregnancy, and the development of Polish trimester-specific reference values of thyroid hormones.
Comprehensive Polish guidelines developed by the Task Force are to systematize the management of the thyroid disorders in pregnant
women in Poland.
(Pol J Endocrinol 2011; 62 (4): 362–381)Jednym z aktualnie szeroko dyskutowanych problemów współczesnej endokrynologii jest opieka tyreologiczna nad kobietą ciężarną.
Powszechnie wiadomo, że dysfunkcja tarczycy może być przyczyną zaburzeń płodności, a nieleczona prawidłowo w czasie ciąży zwiększa
ryzyko powikłań położniczych oraz ma wpływ na rozwój płodu.
Opublikowane w 2007 roku wytyczne Towarzystwa Endokrynologicznego (Endocrine Society), opracowane przy współudziale Towarzystwa
Tyreologicznego Ameryki Łacińskiej (LATS), Towarzystwa Tyreologicznego Azji i Oceanii (AOTA), Amerykańskiego Towarzystwa
Tyreologicznego (ATA) oraz Europejskiego Towarzystwa Tyreologicznego (ETA), w dużym stopniu usystematyzowały zasady postępowania
w chorobach tarczycy w czasie ciąży i w okresie poporodowym. Pomimo ogromnego postępu wiedzy na temat wzajemnego wpływu
ciąży i funkcji gruczołu tarczowego w zdrowiu i chorobie, jaki osiągnięto w ciągu ostatnich kilkunastu lat, nadal pewne obszary wymagają
dalszych badań. W ciągu 3 lat, które minęły od publikacji wytycznych, przybyło danych, które wpłynęły na niektóre zasady prowadzenia
ciężarnej z chorobą tarczycy. Wytyczne nie zawsze mają charakter uniwersalny i nie mogą być w prosty sposób transponowane na społeczeństwa
zróżnicowane etnicznie i ekonomicznie, o odmiennych zwyczajach dietetycznych, w tym w spożyciu nośników jodu, oraz
stosujące odmienne modele profilaktyki jodowej.
W 2008 roku powołano Zespół Ekspertów do spraw Opieki Tyreologicznej w Ciąży. Za cele prac Zespołu przyjęto: opracowanie modelu
opieki nad ciężarną z zaburzeniami funkcji tarczycy, określenie grupy kobiet z ryzykiem zaburzeń funkcji tarczycy wymagających oceny
tyreologicznej podczas planowania ciąży, w trakcie jej trwania oraz w okresie poporodowym — czyli przygotowanie polskich wskazań
do badań przesiewowych oraz ustalenie wartości referencyjnych stężeń hormonów tarczycy w poszczególnych trymestrach ciąży.
Opracowane przez Zespół wytyczne systematyzują zasady opieki tyreologicznej nad kobietą ciężarną w Polsce.
(Endokrynol Pol 2011; 62 (4): 362–381
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