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Researchers at Changwon National University’s Radiation Detector Development Laboratory(RDD) fabricated a single-channel double-GEM(gas electron multiplier) chamber and measured the pulse height distribution of signals produced by exposing the chamber to an Sr-90 source provided by the Korea Research Institute of Standards and Science(KRISS). A beta-ray electron incident on the GEM chamber ionizes gaseous molecules in the drift region of the chamber by means of electromagnetic interactions. After the leased electrons are amplified by electron avalanches in the GEM stages, the multiplied electrons go from the lowest GEM foil toward the anode of the chamber and induce one signal pulse, corresponding to the incident electron, on the readout pad. The charge signal distribution measured during Sr-90 radioactive source irradiation was compared with the simulation done by using a Landau probability distribution. The energy loss distribution of beta-ray electrons, which deposited part of their energy in a thin GEM chamber while traversing gases within the drift region of that chamber, was in good agreement with the calculation of the Landau probability distribution. The pulse height distributions for energy losses of beta-ray electrons incident on the chamber due to Sr-90 disintegrations were observed in order to select a suitable gas mixture for the chamber. The ratios of the Ar/CO2 gas were 75/25, 80/20, 85/15, and 90/10.

A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of $10^{-29}e\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000~TeV., Comment: 8 pages, 3 figures

Fractal is an interesting and important phenomenon which is widely found in nature. Contrary to its importance, fractal is introduced in secondary science textbooks by simple pictures of tree branches or snow crystal without proper explanation. Here we show by annealing a binary film of Al-Au at temperatures at about 200°C a fractal shape growth can be easily observed under a microscope in real time. The paper describes a simple introduction on fractal phenomenon aggregation for high school students and how to make a simple heater for the Au-Al fractal observation.

Sound interference and diffraction is an important part of wave phenomena. Compared to the experiment on the light interference and diffraction, sound experiment is not widely performed at high schools because of the cumbersome equipment. In this experiment, we assembled an array of 256 microphones to measure the sound interference and diffraction. The sound intensity at each microphone was measured using a computer with a multiplexer and 16 analog/digital converting channels. The data were processed using MATLAB software and presented as a 3‐dimensional graphic. The diffraction experiment was done using one speaker and a wall and the interference experiment was done using two speakers. The measurement agreed with the simulation using Excel program. We hope our apparatus can be adopted for a microcomputer‐based experiment at high school physics activity.

Passive isolation systems based on springs are often used to resist vibration due to their low cost and reliability. The basic principle of these systems is that they try to decrease the natural frequency as low as possible. Stiffness of the overall spring system must be low to make the isolator achieve the low natural frequency. An approach to obtain the low dynamic stiffness is the combination of a negative stiffness system and a common isolator. There are, however, a lot of negative stiffness systems, and selecting the best one is difficult. In this paper, mathematical analyses are used to determine the best system that is then applied to construct a vertical isolator of the anti-vibration table.

Summary The inhibitory activity of water extracts from the shoots and roots of three rice cultivars, Taichung native 1 (TN1) and IAC165 (both allelopathic rice) and AUS196 (non-allelopathic rice), grown in hydroponics was evaluated. The release of germination inhibitors by allelopathic rice plants into hydroponic solution was also determined with freshly collected solution and XAD-4 resin desorbate. The degree of the inhibition was quantified in terms of root growth in Echinochloa colona, Echinochloa crus-galli, Echinochloa crus-galli var. oryzicola, Triantema portulacastrum and Lactuca sativa. The allelopathic activity of rice was species specific, and depended on source and concentration. Root length of all test species was inhibited by the different concentrations of shoot extract of allelopathic and non-allelopathic rice. However, of the three cultivars, TN1 showed higher inhibition than IAC165 and AUS196 in all test species. Water extracts of shoots and roots significantly inhibited root growth in E. crus-galli but the shoot extract gave a greater inhibitory effect on E. crus-galli than the root extract. Root exudate of TN1 inhibited root elongation of E. crus-galli from 2 weeks after transplanting (WAT) and the inhibition continued for 4 WAT. The results confirmed the previous finding of a laboratory bioassay that the TN1 had allelopathic activity and produced allelochemicals that inhibit growth of some weed species.

Causes of aliasing that inheres in the fast algorithm, the so-called Mallat algorithm, of discrete wavelet transform (DWT) are explained in detail. Also, an anti-aliasing algorithm for DWT is presented. Both the canonical and the presented algorithm are applied to analyse a typical simulated signal and a vibration signal measured from a defective ball bearing. It is shown that the presented algorithm is quite effective for avoiding aliasing and for extracting impact feature from a complex background.

The Scott-Russel horizontal isolator is a straight line linkage. When this structure is used, the stored energy can be reduced as much as possible, making the isolation system achieve a very low natural frequency. However, because of the existence of the weight of the isolator, the natural frequency is not as low as expected. In this paper, the equation of motion of the Scott-Russel isolator is proposed to find a method to reduce the natural frequency by choosing reasonable parameters and using the zero-length spring.

Calorimeters with a high granularity are a fundamental requirement of the Particle Flow paradigm. This paper focuses on the prototype of a hadron calorimeter with analog readout, consisting of thirty-eight scintillator layers alternating with steel absorber planes. The scintillator plates are finely segmented into tiles individually read out via Silicon Photomultipliers. The presented results are based on data collected with pion beams in the energy range from 8GeV to 100GeV. The fine segmentation of the sensitive layers and the high sampling frequency allow for an excellent reconstruction of the spatial development of hadronic showers. A comparison between data and Monte Carlo simulations is presented, concerning both the longitudinal and lateral development of hadronic showers and the global response of the calorimeter. The performance of several GEANT4 physics lists with respect to these observables is evaluated. Calorimeters with a high granularity are a fundamentalrequirement of the Particle Flow paradigm. This paper focuses on theprototype of a hadron calorimeter with analog readout, consisting ofthirty-eight scintillator layers alternating with steel absorberplanes. The scintillator plates are finely segmented into tilesindividually read out via Silicon Photomultipliers. The presentedresults are based on data collected with pion beams in the energyrange from 8 GeV to 100 GeV. The fine segmentation of thesensitive layers and the high sampling frequency allow for anexcellent reconstruction of the spatial development of hadronicshowers. A comparison between data and Monte Carlo simulations ispresented, concerning both the longitudinal and lateral developmentof hadronic showers and the global response of the calorimeter. Theperformance of several GEANT4 physics lists with respect tothese observables is evaluated. Calorimeters with a high granularity are a fundamental requirement of the Particle Flow paradigm. This paper focuses on the prototype of a hadron calorimeter with analog readout, consisting of thirty-eight scintillator layers alternating with steel absorber planes. The scintillator plates are finely segmented into tiles individually read out via Silicon Photomultipliers. The presented results are based on data collected with pion beams in the energy range from 8GeV to 100GeV. The fine segmentation of the sensitive layers and the high sampling frequency allow for an excellent reconstruction of the spatial development of hadronic showers. A comparison between data and Monte Carlo simulations is presented, concerning both the longitudinal and lateral development of hadronic showers and the global response of the calorimeter. The performance of several GEANT4 physics lists with respect to these observables is evaluated.

Soft tissue sarcomas are rare and account for less than 1% of all newly diagnosed malignancies. One-third of malignant tumors arising in the retroperitoneum are sarcomas. Liposarcoma is the most common soft tissue sarcoma and retroperitoneal sarcoma. Liposarcoma accounts for at least 20% of all sarcomas in adults and up to 41% of all retroperitoneal sarcomas. Here we present the case of a huge retroperitoneal liposarcoma and a brief literature review.A 34-year-old woman was referred to our hospital from a local clinic, because of abdominal distention, pain, and palpable mass. On admission we found that her abdomen was markedly distended. Computed tomography showed a the huge left ovarian mass that occupied almost the entire abdominal cavity. The mass consisted mainly of fat, and calcified material. She was operated under the diagnosis of a huge teratoma. The tumor was located in the retroperitoneal cavity and it abutted the left adnexa. The retroperitoneal tumor, including the left adnexa was removed. The tumor measured 22 x 15 x 11 cm, and showed many histological and pathological findings. On the basis of the histopathological finding, the tumor was diagnosed as a dedifferentiated liposarcoma of the retroperitoneum. The patient is presently undergoing radiation therapy.In retroperitoneal liposarcoma, histological subtype, incomplete resection, contiguous organ resection, and older age are strongly associated with tumor-related mortality. For liposarcoma, it is necessary to customize the treatment strategy on a case-by-case basis.

A prototype module for an International Linear Collider (ILC) detector was built, installed, and tested between 2006 and 2009 at CERN and Fermilab as part of the CALICE test beam program, in order to study the possibilities of extending energy sampling behind a hadronic calorimeter and to study the possibilities of providing muon tracking. The "tail catcher/muon tracker" (TCMT) is composed of 320 extruded scintillator strips (dimensions 1000 mm x 50 mm x 5 mm) packaged in 16 one-meter square planes interleaved between steel plates. The scintillator strips were read out with wavelength shifting fibers and silicon photomultipliers. The planes were arranged with alternating horizontal and vertical strip orientations. Data were collected for muons and pions in the energy range 6 GeV to 80 GeV. Utilizing data taken in 2006, this paper describes the design and construction of the TCMT, performance characteristics, and a beam-based evaluation of the ability of the TCMT to improve hadronic energy resolution in a prototype ILC detector. For a typical configuration of an ILC detector with a coil situated outside a calorimeter system with a thickness of 5.5 nuclear interaction lengths, a TCMT would improve relative energy resolution by 6-16 % for pions between 20 and 80 GeV., 23 pages, 18 figures, 4 tables, submitted to JINST

Application Specific Integrated Circuits, ASICs, similar to those envisaged for the readout electronics of the central calorimeters of detectors for a future lepton collider have been exposed to high-energy electromagnetic showers. A salient feature of these calorimeters is that the readout electronics will be embedded into the calorimeter layers. In this article it is shown that interactions of shower particles in the volume of the readout electronics do not alter the noise pattern of the ASICs. No signal at or above the MIP level has been observed during the exposure. The upper limit at the 95% confidence level on the frequency of fake signals is smaller than 1 × 10 − 5 for a noise threshold of about 60% of a MIP. For ASICs with similar design to those which were tested, it can thus be largely excluded that the embedding of the electronics into the calorimeter layers compromises the performance of the calorimeters.

The CALICE collaboration is studying the design of high performance electromagnetic and hadronic calorimeters for future International Linear Collider detectors. For the hadronic calorimeter, one option is a highly granular sampling calorimeter with steel as absorber and scintillator layers as active material. High granularity is obtained by segmenting the scintillator into small tiles individually read out via silicon photo-multipliers (SiPM). A prototype has been built, consisting of thirty-eight sensitive layers, segmented into about eight thousand channels. In 2007 the prototype was exposed to positrons and hadrons using the CERN SPS beam, covering a wide range of beam energies and incidence angles. The challenge of cell equalization and calibration of such a large number of channels is best validated using electromagnetic processes. The response of the prototype steel-scintillator calorimeter, including linearity and uniformity, to electrons is investigated and described.

We report on the results of an extensive R&D program aimed at the evaluation of Thick-Gas Electron Multipliers (THGEM) as potential active elements for Digital Hadron Calorimetry (DHCAL). Results are presented on efficiency, pad multiplicity and discharge probability of a 10x10 cm2 prototype detector with 1 cm2 readout pads. The detector is comprised of single- or double-THGEM multipliers coupled to the pad electrode either directly or via a resistive anode. Investigations employing standard discrete electronics and the KPiX readout system have been carried out both under laboratory conditions and with muons and pions at the CERN RD51 test beam. For detectors having a charge-induction gap, it has been shown that even a ~6 mm thick single-THGEM detector reached detection efficiencies above 95%, with pad-hit multiplicity of 1.1-1.2 per event; discharge probabilities were of the order of 1e-6 - 1e-5 sparks/trigger, depending on the detector structure and gain. Preliminary beam tests with a WELL hole-structure, closed by a resistive anode, yielded discharge probabilities of, 15 pages, 11 figures, MPGD2011 conference proceeding

Paving the first mile of quality-of-service (QoS) support has become essential for full deployment and utilization of QoS proposals in the Internet. Most of existing efforts have been made to provide network services and control without paying much attention to how applications can use these services. In this paper, we design and implement a two-tier architecture, called QoS Gateway (QoSGW), that acts as an interface between application QoS requirements and network-provided QoS capabilities. The QoSGW is to support small embedded network devices that rely on network-provided QoS. Our architecture, in its full version, is composed of two key components: (i) an agent that resides on the end-host and provides an adequate interface for QoS-dependent applications, and (ii) a QoS manager that provides an interface to network services for the agents. Using these two components enhances generality and scalability in providing QoS support for Internet applications and end-devices. The QoSGW is intended to promote QoS deployment and facilitate construction of QoS-aware access networks.

Metaplastic carcinoma of the breast is a rare disease. We describe the MRI findings with the correlative sonographic and pathologic features of two cases. On MRI, T2‐weighted images demonstrate a relatively well‐defined mass with high signal intensity cystic components. Dynamic enhancement subtraction images showed an early enhancing and delayed washout peripheral rim and non‐enhancing internal components. A microlobulated, isoechogenic mass with cystic components was seen sonographically, and was histopathology related to necrosis and cystic degeneration. Although these features are not unique, metaplastic carcinoma should be included in the differential diagnosis for breast masses.

The relationship between cerebrovascular disease and an insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene is still being debated. The frequency of the DD genotype of the ACE gene was significantly higher in subjects with than those without cerebral infarction in Japan. The aim of the present study was to assess the relationship between ACE gene polymorphism and the development of cerebral infarction in a population from Korea. We examined its possible role as a risk factor in patients with cerebral infarction. The association between ACE gene polymorphism and cerebral infarction was examined in 106 patients with cerebral infarction and 498 controls without cerebral infarction. Frequencies of the genotypes and alleles of the ACE gene were investigated. The ACE genotype was analyzed by the polymerase chain reaction (PCR). The frequency of D allele was 37.7% in patients and 39.1% in controls (chi2 = 0.128, p = 0.720). The frequencies of the genotypes of the ACE gene were II: 39.6%, ID: 45.3%, and DD: 15.1% in patients, and II: 37.1%, ID: 47.6%, and DD: 15.3% in controls (chi2 = 0.127, p = 0.721). There was no significant difference in the frequency of the DD genotype of the ACE gene, and we did not find any association between ACE polymorphism and cerebral infarction. These results indicate that ACE polymorphism is not a risk factor for the development of cerebral infarction in a Korean population.

Parathyroid carcinoma is a rare endocrine malignancy characterized by the exaggerated metabolic effects of the parathyroid glands. The preoperative differential diagnosis between parathyroid carcinoma and primary hyperparathyroidism is often difficult because many of the signs and symptoms are very similar. Intraoperative differentiation is obscured by the strict anatomic and histologic criteria required for diagnosis of parathyroid carcinoma. We have encountered three patients with parathyroid carcinoma during the last 10 years and managed them successfully. Two of them presented with recurrence of hypercalcemia, one 11 years after and the other 3 years after the primary operation for hyperparathyroidism; both patients were eventually diagnosed with parathyroid carcinoma. The third case was suspected as primary hyperparathyroidism preoperatively but confirmed as carcinoma subsequent to histologic examination.

The Tal1 oncogene is a class II basic helix-loop-helix (bHLH) transcription factor, overexpressed in as much as 60% of T cell acute lymphoblastic leukemia cases. Like other class II bHLH proteins, Tal1 can heterodimerize with the class I bHLH proteins, such as E47, and bind to a DNA recognition sequence termed E box. Therefore, it is believed that the oncogenic capacity of Tal1 lies in its ability, as a heterodimer with E47, to activate aberrantly a set of "leukemogenic" genes in T cells. However, compared with E47 homodimers, Tal1/E47 heterodimers are very poor transactivators. Thus the effect of Tal1 is actually to inhibit E47 homodimer activity. Here we propose that the transforming properties of Tal1 are the result of its ability to inhibit E47 activity. We address the mechanism of Tal1 inhibition and demonstrate that Tal1/E47 heterodimers cannot activate transcription because their respective activation domains are incompatible. Furthermore, we present data showing that Tal1 can inhibit E47-mediated activation of the CIP1 gene. Finally, we demonstrate that Tal1 inhibits E47 activity in leukemic T cells.

TAL1 is a basic helix-loop-helix (bHLH) protein involved in hematopoietic development. In T cell acute lymphoblastic leukemic cells, TAL1 is aberrantly overexpressed and is thought to contribute to oncogenesis. To identify proteins that interact with TAL1 in mediating leukemogenesis, we used TAL1 as a bait in a two-hybrid interaction screen, and isolated a cDNA clone that encodes a unique GTP binding protein, DRG. The interaction between DRG and TAL1 was confirmed both in vitro and in vivo. DRG was also shown to bind in vitro to two TAL1-related proteins, TAL2 and Lyl1. Mutational analyses showed that the HLH domain of TAL1 was necessary and sufficient for its interaction with the C-terminus of DRG. Furthermore, while DRG and E47 compete to interact with TAL1, TAL1 binds to DRG and E47 in a mutually exclusive manner. In rat embryonic fibroblast transformation assays, DRG stimulated the cotransforming activity of c-myc and ras. Based on these results, DRG appears to be a potential target for TAL-like oncoproteins.

The neurotoxic effects of methylmercury on cerebral neuron cultures derived from neonatal mouse were studied. Exposure of cerebral neurons to methylmercury chloride resulted in significant cell damage and death in a time-dependent manner in cerebral neuron cultures. The methylmercury neurotoxicity was blocked by oxygen radical scavengers such as glutathione, catalase, selenium, and cysteine. Antagonists of the N-methyl-D-aspartate (NMDA) receptor, including MK-801 (a non-competitive NMDA antagonist), D-2-amino-5-phosphonovaleric acid (APV) (a competitive NMDA antagonist), and 7-chlorokynurenic acid (an antagonist at the glycine site associated with the NMDA receptor), similarly blocked methylmercury-induced neurotoxicity in cerebral neuron cultures. These results indicate that both oxygen radicals and excitotixic amino acids are involved in the methylmercury-induced neurotoxicity of cerebral neuron cultures.

FK506-binding protein (FKBP) catalyzes the cis-trans isomerization of the peptidyl-prolyl amide bond (the PPIase reaction) and is the major intracellular receptor for the immunosuppressive drugs FK506 and rapamycin. One mechanism proposed for catalysis of the PPIase reaction requires attack of an enzyme nucleophile on the carbonyl carbon of the isomerized peptide bond. An alternative mechanism requires conformational distortion of the peptide bond with or without assistance by an enzyme hydrogen bond donor. We have determined the kinetic parameters of the human FKBP-catalyzed PPIase reaction. At 5 degrees C, the isomerization of Suc-Ala-Leu-Pro-Phe-pNA proceeds in 2.5% trifluorethanol with kcat = 600 s-1, Km = 0.5 mM and kcat/Km = 1.2 x 10(6) M-1s-1. The kcat/Km shows little pH dependence between 5 and 10. A normal secondary deuterium isotope effect is observed on both kcat and kcat/Km. To investigate dependence on enzyme nucleophiles and proton donors, we have replaced eight potential catalytic residues with alanine by site-directed mutagenesis. Each FKBP variant efficiently catalyzes the PPIase reaction. Taken together, these data support an unassisted conformational twist mechanism with rate enhancement due in part to desolvation of the peptide bond at the active site. Fluorescence quenching of the buried tryptophan 59 residue by peptide substrate suggests that isomerization occurs in a hydrophobic environment.

Department of Physics, University of Texas, Arlington, TX 76019, U.S.A.(Received 12 September 2006)Performance tests of a single channel double Gas Electron multiplier (GEM) detector constructedby the Radiation Detector Development Group of Changwon National University (CNU) and amulti-channel double GEM chamber constructed by the High Energy Physics Group of the Univer-sity of Texas at Arlington was carried out at the Korea Atomic Energy Research Institute (KAERI’s)RF accelerator by using 10-MeV electron beams during May 20 - 26, 2006. In this experiment, weobserved signals by both 10-MeV beam electrons and X-ray photons in the CNU single-channeldouble GEM chamber and in the UTA chamber by using an oscilloscope and photographed wave-forms. By analyzing the chamber output signals on the oscilloscope, computing the number ofX-rays photons produced by bremsstrahlung of the beam electrons in a 2-mm lead plate, calculat-ing the angular distribution of beam electrons caused by multiple scatterings in the lead plate, andestimating the interaction probabilities of X-ray photons in the lead plate, the Ar/CO

The studies presented in this paper provide a first experimental test of the Particle Flow Algorithm (PFA) concept using data recorded in high granularity calorimeters. Pairs of overlaid pion showers from CALICE 2007 test beam data are reconstructed by the PandoraPFA program developed to implement PFA for a future lepton collider. Recovery of a neutral hadron's energy in the vicinity of a charged hadron is studied. The impact of the two overlapping hadron showers on energy resolution is investigated. The dependence of the confusion error on the distance between a 10 GeV neutral hadron and a charged pion is derived for pion energies of 10 and 30 GeV which are representative of a 100 GeV jet. The comparison of these test beam data results with Monte Carlo simulation is done for various hadron shower models within the GEANT4 framework. The results for simulated particles and for beam data are in good agreement thereby providing support for previous simulation studies of the power of Particle Flow Calorimetry at a future lepton collider. CALICE 2007 test beam data were used to test the PandoraPFA program. The program capability to recover a neutral hadron energy in the vicinity of a charged hadron was studied. The impact of overlapping of two hadron showers on energy resolution was investigated. The dependence of the confusion error on the distance between a 10 GeV neutral hadron and a charged pion was derived for pion energies of 10 and 30 GeV which are representative of a 100 GeV jet. The comparison of these test beam data results with Monte Carlo simulation was done for LHEP and QGSP BERT physics lists. The probability of correct recovering of neutral hadron energy has been calculated. The dependence of the confusion error on the neutral hadron energy was also studied. The confusion error averaged over 100 GeV jet fragment energies has been estimated for the case of one neutral and one charged hadron.