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

100 kV Schottky electron gun

We present a comparison between experimental results and computer calculations on a high current, high resolution single lens electrostatic 100 kV Schottky electron gun. One promising application for such an electron gun is for direct electron‐beam patterning of x‐ray masks. The high energy helps provide precise patterning of the thick resist, maintains vertical resist profiles, and minimizes the proximity effect. The gun was designed to operate from 25 to 100 kV, capable of focus at a distance of 145–245 mm with a magnification of 1.15. The emitter, of apex radius ∼0.6 μm operated at 1800 K in the extended Schottky regime, provides an angular intensity of 0.5 mA/sr for an extraction voltage of 5000 V and with a beam limiting aperture of 2.2 mrad, the gun delivers 7 nA of probe current. The gun consists of a replaceable high voltage optic module mounted on a precision insulator with the main acceleration occurring between the exit of the optic module and the grounded anode. A provision is made for alignment of the emitter with respect to the central optical axis of the optic module in a special alignment chamber eliminating the need for high voltage emitter alignment. Final gun alignment is achieved by X–Y motion of the grounded anodeaperture. The gun is constructed to allow ease of replacement of the emitter, the beam defining aperture, and the differential pumping aperture. The beam supply has 10 ppm of ripple while lens supplies have supply, cabling, connectors,insulator, and optic module draw 1 μA of ground leakage current. Pressured SF6 chambers are used for high voltage connector interfaces within the power supply and on the gun

Gender score development in the Berlin Aging Study II: A retrospective approach

In addition to biological sex, gender, defined as the sociocultural dimension of being a woman or a man, plays a central role in health. However, there are so far few approaches to quantify gender in a retrospective manner in existing study datasets. We therefore aimed to develop a methodology that can be retrospectively applied to assess gender in existing cohorts. We used baseline data from the Berlin Aging Study II (BASE-II), obtained in 2009-2014 from 1869 participants aged 60 years and older. We identified 13 gender-related variables and used them to construct a gender score by using primary component and logistic regression analyses. Of these, nine variables contributed to a gender score: chronic stress, marital status, risk-taking behaviour, personality attributes: agreeableness, neuroticism, extraversion, loneliness, conscientiousness, and level of education. Females and males differed significantly in the distribution of the gender score, but a significant overlap was also found. Thus, we were able to develop a gender score in a retrospective manner from already collected data that characterized participants in addition to biological sex. This approach will allow researchers to introduce the notion of gender retrospectively into a large number of studies

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

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

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

Android malware detection through generative adversarial networks

© 2019 John Wiley & Sons, Ltd. Mobile and cell devices have empowered end users to tweak their cell phones more than ever and introduce applications just as we used to with personal computers. Android likewise portrays an uprise in mobile devices and personal digital assistants. It is an open-source versatile platform fueling incalculable hardware units, tablets, televisions, auto amusement frameworks, digital boxes, and so forth. In a generally shorter life cycle, Android also has additionally experienced a mammoth development in application malware. In this context, a toweringly large measure of strategies has been proposed in theory for the examination and detection of these harmful applications for the Android platform. These strategies attempt to both statically reverse engineer the application and elicit meaningful information as features manually or dynamically endeavor to quantify the runtime behavior of the application to identify malevolence. The overgrowing nature of Android malware has enormously debilitated the support of protective measures, which leaves the platforms such as Android feeble for novel and mysterious malware. Machine learning is being utilized for malware diagnosis in mobile phones as a common practice and in Android distinctively. It is important to specify here that these systems, however, utilize and adapt the learning-based techniques, yet the overhead of hand-created features limits ease of use of such methods in reality by an end user. As a solution to this issue, we mean to make utilization of deep learning–based algorithms as the fundamental arrangement for malware examination on Android. Deep learning turns up as another way of research that has bid the scientific community in the fields of vision, speech, and natural language processing. Of late, models set up on deep convolution networks outmatched techniques utilizing handmade descriptive features at various undertakings. Likewise, our proposed technique to cater malware detection is by design a deep learning model making use of generative adversarial networks, which is responsible to detect the Android malware via famous two-player game theory for a rock-paper-scissor problem. We have used three state-of-the-art datasets and augmented a large-scale dataset of opcodes extracted from the Android Package Kit bytecode and used in our experiments. Our technique achieves F1 score of 99% with a receiver operating characteristic of 99% on the bytecode dataset. This proves the usefulness of our technique and that it can generally be adopted in real life

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

The Enzymatic Activity of Type 1 Iodothyronine Deiodinase (D1) is Low in Liver Hemangioma: A Preliminary Study

Type 1 iodothyronine deiodinase (D1) is a crucial enzyme which converts the prohormone thyroxine (T4) into active tri-iodothyronine (T3). There has been strong evidence that the metabolism of thyroid hormones is disturbed in some neoplastic tissues such as thyroid, renal, and breast cancer. However, there are few available data about D1 enzyme activity in benign tumors such as hemangioma, which is the most common primary liver tumor. Hence this study aimed to determine the enzymatic activity of D1 in hemangiomas in relation to healthy liver tissue. Seven tumors and healthy control tissues were obtained from patients who had liver resection due to hemangioma. The activity was assessed by measurement of radioactive iodine released by deiodination catalyzed by D1. It was found that D1 activity was significantly lower in the hemagiomas than in the healthy surrounding tissue (p = 0.0017). The results indicated that thyroid hormones play important roles not only in the regulation of cell metabolism, but also in cell growth, division, and apoptosis. The active form T3 acts through its nuclear receptors and influences the up- and down-regulation of target genes. Healthy liver tissue expresses a high level of D1, but disturbed D1 activity may result in changes in the local concentration of T3 which may impair gene transcription. These finding demonstrate a low enzymatic activity of D1 in liver hemangioma and suggest an as yet unknown role of thyroid hormones in this type of benign liver tumor