Showing papers by "Jie Zhang published in 2009"
Southern Methodist University1, California Institute of Technology2, Case Western Reserve University3, University of Zurich4, University of Florida5, Fermilab6, Stanford University7, University of California, Santa Barbara8, University of Minnesota9, University of California, Berkeley10, Massachusetts Institute of Technology11, University of Colorado Denver12, Syracuse University13, Texas A&M University14, Queen's University15, St. Olaf College16, Lawrence Berkeley National Laboratory17, Santa Clara University18
TL;DR: The results from the completed Cryogenic Dark Matter Search (CDMS II) experiment, which searched for dark matter in the form of weakly interacting massive particles (WIMP), cannot be interpreted with confidence as evidence for WIMP interactions, but neither event can be ruled out as representing signal.
Abstract: We report results from a blind analysis of the final data taken with the Cryogenic Dark Matter Search experiment (CDMS II) at the Soudan Underground Laboratory, Minnesota, USA. A total raw exposure of 612 kg-days was analyzed for this work. We observed two events in the signal region; based on our background estimate, the probability of observing two or more background events is 23%. These data set an upper limit on the Weakly Interacting Massive Particle (WIMP)-nucleon elastic-scattering spin-independent cross-section of 7.0 x 10{sup -44} cm{sup 2} for a WIMP of mass 70 GeV/c{sup 2} at the 90% confidence level. Combining this result with all previous CDMS II data gives an upper limit on the WIMP-nucleon spin-independent cross-section of 3.8 x 10{sup -44} cm{sup 2} for a WIMP of mass 70 GeV/c{sup 2}. We also exclude new parameter space in recently proposed inelastic dark matter models.
903 citations
TL;DR: In this article a coverage and interference analysis based on a realistic OFDMA macro/femtocell scenario is provided, as well as some guidelines on how the spectrum allocation and interference mitigation problems can be approached in these networks.
Abstract: OFDMA femtocells have been pointed out by the industry as a good solution not only to overcome the indoor coverage problem but also to deal with the growth of traffic within macrocells. However, the deployment of a new femtocell layer may have an undesired impact on the performance of the macrocell layer. The allocation of spectrum resources and the avoidance of electromagnetic interference are some of the more urgent challenges that operators face before femtocells become widely deployed. In this article a coverage and interference analysis based on a realistic OFDMA macro/femtocell scenario is provided, as well as some guidelines on how the spectrum allocation and interference mitigation problems can be approached in these networks. Special attention is paid to the use of self-configuration and self-optimization techniques for the avoidance of interference.
892 citations
TL;DR: Numerical results show that the proposed PF scheduler provides a superior fairness performance with a modest loss in throughput, as long as the user average SINRs are fairly uniform.
Abstract: The challenge of scheduling user transmissions on the downlink of a long term evolution (LTE) cellular communication system is addressed. A maximum rate algorithm which does not consider fairness among users was proposed in . Here, a multiuser scheduler with proportional fairness (PF) is proposed. Numerical results show that the proposed PF scheduler provides a superior fairness performance with a modest loss in throughput, as long as the user average SINRs are fairly uniform. A suboptimal PF scheduler is also proposed, which has a much lower complexity at the cost of some throughput degradation.
270 citations
01 Sep 2009
TL;DR: 2 novel approaches for the self-organization of Orthogonal Frequency Division Multiple Access (OFDMA) femtocells are presented, in which the femtocell is able to dynamically sense the air interface and tune its sub-channel allocation in order to reduce inter-cell interference and enhance system capacity.
Abstract: This work presents 2 novel approaches for the self-organization of Orthogonal Frequency Division Multiple Access (OFDMA) femtocells, in which the femtocell is able to dynamically sense the air interface and tune its sub-channel allocation in order to reduce inter-cell interference and enhance system capacity. In the sensing phase, these techniques make use of either messages broadcast by the femtocells or measurements reported by the users, while in the tuning phase, they provide a good solution for the frequency assignment problem. Results shows that it is recommend to use information collected at the user position (measurement reports), when devising self-organization algorithms for tuning the parameters of femtocells.
132 citations
TL;DR: In this article, a visible light TiO2 photocatalyst was prepared by a surface chemical modification process with toluene 2,4-diisocyanate (TDI).
124 citations
TL;DR: In this paper, the authors presented updated measurements of time-dependent CP asymmetries in fully reconstructed neutral B decays containing a charmonium meson using the BABAR detector at the PEP-II asymmetric energy e(+)e(-) storage rings operating at the SLAC National Accelerator Laboratory.
Abstract: We present updated measurements of time-dependent CP asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 +/- 5)x10(6) Upsilon(4S)-> B B decays collected with the BABAR detector at the PEP-II asymmetric energy e(+)e(-) storage rings operating at the SLAC National Accelerator Laboratory. The time-dependent CP asymmetry parameters measured from J psi K-S(0), J psi K-L(0), psi(2S)K-S(0), eta K-c(S)0, chi K-c1(S)0, and J/psi K-*(892)(0) decays are: C-f=0.024 +/- 0.020(stat)+/- 0.016(syst) and -eta S-f(f)=0.687 +/- 0.028(stat)+/- 0.012(syst).
100 citations
01 Sep 2009
TL;DR: The performance of the model is evaluated and it is shown that limited access contributes to seriously reduce cross-layer interference while guaranteeing a minimum performance to the femtocell subscribers.
Abstract: Femtocells are a promising solution for the provision of high indoor coverage and capacity. Furthermore, OFDMA-based femtocells have proven to be highly versatile when dealing with cross-layer co-channel interference thanks to the allocation of frequency subchannels. However, concerns still exist related to the impact of the different access methods to femtocells in an overlayed network. Femtocells based on a Closed Subscribers Group, where only device owners are allowed connectivity introduce severe interference to macrocell users. On the other hand, Open Access femtocells where any user can connect, does not bring many advantages to the femtocell owner. In this paper, an intermediate access method based on a limited access is proposed. The performance of the model is evaluated throughout systemlevel simulations and it is shown that limited access contributes to seriously reduce cross-layer interference while guaranteeing a minimum performance to the femtocell subscribers.
83 citations
05 Jan 2009
TL;DR: In this paper, a detailed study of the expected performance of the ATLAS detector is presented, together with the reconstruction of tracks, leptons, photons, missing energy and jets, along with the performance of b-tagging and the trigger.
Abstract: A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN.
78 citations
TL;DR: A novel poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor is tested to enhance the effect of radiotherapy in a xenograft model of human head and neck squamous cell carcinoma (HNSCC).
Abstract: Background
In this study, we tested the ability of a novel poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor, 10-(4-methyl-piperazin-1-ylmethyl)-2H-7-oxa-1,2-diaza-benzo[de]-anthracen-3-one (GPI-15427), to enhance the effect of radiotherapy in a xenograft model of human head and neck squamous cell carcinoma (HNSCC).
Methods
Human xenograft HNSCC tumors were established in female nude mice: animals were treated with orally administered GPI-15427 at varied doses prior to tumor irradiation. In vitro and in vivo apoptosis analyses and neutral single-cell gel electrophoresis (comet) assay were performed, with the “tail moment” calculated to evaluate DNA double-strand break damage.
Results
Orally administered GPI-15427 given before radiation therapy significantly reduced tumor volume, and cells demonstrated significantly elevated mean tail moments (indicative of DNA damage) and enhanced apoptosis both in vitro and in vivo, compared with radiation-alone and control groups.
Conclusions
Use of the PARP-1 inhibitor GPI-15427 induced significant sensitization to radiotherapy, representing a promising new treatment in the management of HNSCC. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
67 citations
TL;DR: In this paper, the finite-difference time-domain (FDTD) method is adapted for the computation of radiowave propagation predictions at WiMAX frequencies and is particularly suitable for the study of hybrid indoor/outdoor scenarios and thus well adapted forThe case of WiMAX femtocells in residential environments.
Abstract: Femtocells, or home base stations, are a potential future solution for operators to increase indoor coverage and reduce network cost. In a real WiMAX femtocell deployment in residential areas covered by WiMAX macrocells, interference is very likely to occur both in the streets and certain indoor regions. Propagation models that take into account both the outdoor and indoor channel characteristics are thus necessary for the purpose of WiMAX network planning in the presence of femtocells. In this paper, the finite-difference time-domain (FDTD) method is adapted for the computation of radiowave propagation predictions at WiMAX frequencies. This model is particularly suitable for the study of hybrid indoor/outdoor scenarios and thus well adapted for the case of WiMAX femtocells in residential environments. Two optimization methods are proposed for the reduction of the FDTD simulation time: the reduction of the simulation frequency for problem simplification and a parallel graphics processing units (GPUs) implementation. The calibration of the model is then thoroughly described. First, the calibration of the absorbing boundary condition, necessary for proper coverage predictions, is presented. Then a calibration of the material parameters that minimizes the error function between simulation and real measurements is proposed. Finally, some mobile WiMAX system-level simulations that make use of the presented propagation model are presented to illustrate the applicability of the model for the study of femto- to macrointerference.
64 citations
TL;DR: In this paper, the effects of surface fluorination on the photocatalytic activity and hydrophilicity of porous surface-fluorinated TiO 2 (F-TiO 2 ) films were studied.
TL;DR: ParP activation is implicated in the formation of diabetic cataract and in early retinal changes, and these findings provide a rationale for the development of PARP inhibitors for the prevention of diabetic ocular complications.
Abstract: Purpose This study evaluated the role for poly(ADP-ribose) polymerase (PARP) in diabetes-induced cataractogenesis and early retinal changes. Methods Control and streptozotocin (STZ)-diabetic rats were treated with or without the PARP inhibitors 1,5-isoquinolinediol (ISO; 3 mg kg(-1) d(-1) intraperitoneally) and 10-(4-methyl-piperazin-1-ylmethyl)-2H-7-oxa-1,2-diaza-benzo[de]anthracen-3-1 (GPI-15427, 30 mg kg(-1) d(-1) orally) for 10 weeks after the first 2 weeks without treatment. Lens clarity was evaluated by indirect ophthalmoscopy and slit lamp examination, and retinal changes were evaluated by immunohistochemistry and Western blot analysis. In in vitro studies, cultured human lens epithelial cells and bovine retinal pericytes and endothelial cells were exposed to high glucose or palmitate. Results PARP is expressed in lens, and poly(ADP-ribosyl)ated proteins are primarily localized in the 38- to 87-kDa range of the protein spectrum, with several minor bands at 17 to 38 kDa. The 38- to 87-kDa and the 17- to 38-kDa poly(ADP-ribosyl)ated protein expression increased by 74% and 275%, respectively, after 4 weeks of diabetes and by approximately 65% early after exposure of lens epithelial cells to 30 mM glucose. Both PARP inhibitors delayed, but did not prevent, the formation of diabetic cataract. The number of TUNEL-positive nuclei in flatmounted retinas increased approximately 4-fold in STZ diabetic rats, and this increase was prevented by ISO and GPI-15427. Both PARP inhibitors reduced diabetes-induced retinal oxidative-nitrosative and endoplasmic reticulum stress and glial activation. GPI-15427 (20 microM) prevented oxidative-nitrosative stress and cell death in palmitate-exposed pericytes and endothelial cells. Conclusions PARP activation is implicated in the formation of diabetic cataract and in early retinal changes. These findings provide a rationale for the development of PARP inhibitors for the prevention of diabetic ocular complications.
TL;DR: Chen et al. as mentioned in this paper presented the baseline values of clinical chemistry and hematology parameters in normal Chinese rhesus monkeys (Macaca mulatta) of either sex, 3 to 5 years old.
Abstract: Chen Y, Qin S, Ding Y, Wei L, Zhang J, Li H, Bu H, Lu Y, Cheng J. Reference values of clinical chemistry and hematology parameters in rhesus monkeys (Macaca mulatta). Xenotransplantation 2009; 16: 496–501. © 2009 John Wiley & Sons A/S.
Abstract: Background: Rhesus monkey models are valuable to the studies of human biology. Reference values for clinical chemistry and hematology parameters of rhesus monkeys are required for proper data interpretation.
Methods: Whole blood was collected from 36 healthy Chinese rhesus monkeys (Macaca mulatta) of either sex, 3 to 5 yr old. Routine chemistry and hematology parameters, and some special coagulation parameters including thromboelastograph and activities of coagulation factors were tested.
Results and conclusion: We presented here the baseline values of clinical chemistry and hematology parameters in normal Chinese rhesus monkeys. These data may provide valuable information for veterinarians and investigators using rhesus monkeys in experimental studies.
14 Jun 2009
TL;DR: It is found that a limited amount of feedback information can provide a relatively good performance of the novel optimal multiuser scheduler proposed and its performance is evaluated.
Abstract: The problem of allocating resources for user transmissions on the downlink of a Long Term Evolution (LTE) cellular communication system is studied. A novel optimal multiuser scheduler is proposed and its performance is evaluated. Numerical results show that the system performance improves with increasing correlation among OFDMA sub-carriers. It is found that a limited amount of feedback information can provide a relatively good performance. A sub-optimal scheduler with a lower computational complexity is also proposed, and shown to provide good performance. The sub-optimal scheme is especially attractive when the number of users is large, as the complexity of the optimal scheme may be unacceptably high in many practical situations.
TL;DR: In this article, the authors fabricate transparent MgAl(2)O(4) nano-ceramics, which are composed of 40 nm grains, by sintering under high pressure and low temperatures.
Abstract: We fabricate transparent MgAl(2)O(4) nano-ceramics, which are composed of 40 nm grains, by sintering under high pressure and low temperatures. Analysis of the grain size, differential strains, yield strength and porosity obtained from transmission electron microscopy and x-ray diffraction indicates that the pores at the grain boundary triple junctions can retard grain boundary migration and thus prevent grain growth. It is found that the relatively high density for MgAl(2)O(4) nano-ceramics produced at low-temperature and high pressure is attributed mainly to the large energy in the grain exteriors. The decrease in the transparency with increasing temperature (> 700 degrees C) is therefore a result of the light scattering at large pores. On the basis of these results, we propose a mechanism of transparency in MgAl(2)O(4) nano-ceramics.
30 Nov 2009
TL;DR: A way to deal with the trade-offs generated during the LTE Access network design is described, and a service-oriented optimization framework that offers a new perspective for this process with consideration of the technical and economic factors of this kind of networks is presented.
Abstract: With the emergence of new technologies and services, it is very important to accurately identify the factors that affect the design of the wireless access network and define how to take them into account to achieve optimally performing and cost-efficient networks. Till now, most existing efforts have been focused the basic access capability. This article describes a way to deal with the trade-offs generated during the LTE Access network design, and presents a service-oriented optimization framework that offers a new perspective for this process with consideration of the technical and economic factors of this kind of networks. We propose a mixed integer programming model with the use of the method of the Pareto front and Multiobjective Tabu Search. An example of deployment is presented.
26 Apr 2009
TL;DR: This work introduces a novel approach to the frequency as-signment problem called Dynamic Frequency Planning (DFP) tai-lored to OFDMA networks that dynamicallyadapts the radio frequency parameters to the environment taking the user and channel conditions into account.
Abstract: —In order to avoid inter-cell interference, OFDMAnetworks are flexible in terms of radio resource managementtechniques, supporting different frequency reuse schemes (FRSs),which in turn, may decrease inter-cell interference and increasenetwork performance. However, because most of them are basedon fix patterns, these FRSs cannot cope with the uneven distri-bution and dynamic behavior of the traffic throughout the day.This work introduces a novel approach to the frequency as-signment problem called Dynamic Frequency Planning (DFP) tai-lored to OFDMA networks. The proposed approach dynamicallyadapts the radio frequency parameters to the environment takingthe user and channel conditions into account. Moreover, a variantof DFP, called vertical DFP, based on the fractional frequencyreuse schemes (FFRSs) concept is proposed. In comparison tothe traditional FRSs, these techniques notably mitigate inter-cellinterference and enhance network performance. I. I NTRODUCTION Interference has been proven to be the major problem ofwireless communication systems across the years, because:
TL;DR: In this article, the authors investigated the optimal scale of pay-as-you-go social security in a dynastic family model with human capital externalities, fertility and endogenous growth.
TL;DR: In this article, the beam spin asymmetry in Deeply Virtual Compton Scattering (DVCS) at an electron beam energy of 4.8$ GeV using the CLAS detector at the Thomas Jefferson National Accelerator Facility was measured.
Abstract: We report measurements of the beam spin asymmetry in Deeply Virtual Compton Scattering (DVCS) at an electron beam energy of $4.8$ GeV using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The DVCS beam spin asymmetry has been measured in a wide range of kinematics, $1$(GeV/c)$^2$ $
TL;DR: In this paper, the response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c has been measured.
Abstract: The response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c has been measured. To our knowledge, this is the widest range of momenta in which any calorimeter system has been studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. The analysis of the differences in calorimeter response to charged pions, kaons, protons and antiprotons and a detailed discussion of the underlying phenomena are presented. We also show techniques that apply corrections to the signals from the considerably different electromagnetic (EB) and hadronic (HB) barrel calorimeters in reconstructing the energies of hadrons. Above 5 GeV/c, these corrections improve the energy resolution of the combined system where the stochastic term equals 84.7±1.6% and the constant term is 7.4±0.8%. The corrected mean response remains constant within 1.3% rms.
TL;DR: The results indicated that recombinant BMP6 induced ALP activity in a dose-dependent and time-course-dependent manner and ameliorated the TGF-β1-induced changes in HK-2 cells.
Abstract: The aim of the study was to investigate the potential role of BMP6 in TGF-β1-mediated changes in HK-2 cells. BMP6 was purified via heparin affinity and reverse phase liquid chromatography. The purity, specificity, and bioactivity of BMP6 were determined by SDS-PAGE, Western blot assays, and the induction of alkaline phosphatase (ALP) activity, respectively. Cell proliferation, morphology, and expression levels of α-SMA and E-cadherin were assessed by cell viability, microscopy, and Western blot assays, respectively. In addition, cell adhesion abilities were determined by counting the number of attached cells. The expression of fibronectin, collagen IV, matrix metalloproteinases 2 (MMP-2), and tissue inhibitors of matrix metalloproteinases 2 (TIMP-2) were analyzed using RT-PCR. MMP-2 activity was analyzed by zymography, whereas the activation of the MAPKs and Smad signaling were analyzed using Western blot assays and a reporter gene assay, respectively. Our results indicated that recombinant BMP6 induced ALP activity in a dose-dependent and time-course-dependent manner. Treatment with TGF-β1 reduced both the cell proliferation and the expression of E-cadherin, induced a morphological transformation, decreased the expression and activity of MMP-2, and increased the expression levels of α-SMA, fibronectin, and TIMP-2 in HK-2 cells. All of these effects were inhibited when cells were treated with TGF-β1 in combination with rhBMP6, whereas rhBMP6 alone demonstrated no such effect. Treatment with TGF-β1, rhBMP6, or a combination of both had no effect on the expression of collagen IV. In addition, the administration of rhBMP6 prevented the enhanced adhesion behavior triggered by TGF-β1. Furthermore, the addition of rhBMP6 abrogated the JNK and Smad2/3 signaling that was activated by TGF-β1. BMP6 ameliorated the TGF-β1-induced changes in HK-2 cells. The suppression of TGF-β1-mediated JNK and Smad2/3 signaling activation were implicated in these effects.
Journal Article•
TL;DR: After fifteen years, the prevalence of H. pylori infection among both children and adults remained significantly higher in areas with a high incidence of gastric cancer in China compared with that in Areas with a low incidence of Gastric cancer.
Abstract: BACKGROUND The prevalence of Helicobacter pylori (H. pylori) infection varies by geographic locations. Studies indicate that the infection rate of H. pylori was previously high in China but that rates had been declining worldwide over recent decades. THE AIMS OF OUR STUDY WERE (1) to determine the current prevalence of H. pylori infection among children and adults residing in areas with high (Muping County, Shandong) and low (Yanqing County, Beijing) incidences of gastric cancer in China, and (2) to compare the prevalence for 2006 with the prevalence for the early 1990s. METHODS Using Warthin-Starry silver staining of gastric mucosal biopsy specimens and H. pylori stool antigen tests (HpSA), we tested a total of 2065 asymptomatic children aged 8 - 15 years and adults aged 40 - 79 years in the above two regions from May to July 2006. We evaluated 520 children and 526 adults from Muping, and 516 children and 503 adults from Yanqing. Subjects were selected randomly and H. pylori status was determined by HpSA in children and either HpSA or histology of gastric biopsies in adults. Data obtained in the early 1990s in the same two areas of China were also collected and studied. RESULTS For children, the prevalence of H. pylori infection was significantly higher in Muping (37.69%) than it was in Yanqing (25.58%, P 0.05). From 1991 to 2006 H. pylori prevalence among 8 - 10-year-old children decreased in Muping (60.00% vs 32.07%, P 0.05). In the adult group, H. pylori prevalence was 50.95% in Muping, which was significantly higher than the 41.35% positive rate in Yanqing (P < 0.01). But there were no statistically significant differences between different age groups of 40 - 49, 50 - 59, and 60 - 79 years, or between males and females. A significant decrease in H. pylori prevalence in both regions was observed when the results of 2006 were compared with the data obtained in 1990 in Muping (50.95% vs 73.78%, P < 0.001) and in 1992 in Yanqing (41.35% vs 55.35%, P < 0.01). CONCLUSIONS After fifteen years, the prevalence of H. pylori infection among both children and adults remained significantly higher in areas with a high incidence of gastric cancer in China compared with that in areas with a low incidence of gastric cancer. H. pylori infection rates have decreased in the general Chinese population during recent years.
TL;DR: This study has provided novel findings of a dual mechanism for BMP-6-regulated deltaEF1 expression in breast cancer cells, involving cross-talks between AP-1-mediated transcriptional repression and miRs-mediated translational inhibition.
TL;DR: In this paper, the authors explore how retirement timing, together with life-cycle saving and human capital investment in children, responds to rising longevity in a recursive model with altruistic agents.
Abstract: This paper explores how retirement timing, together with life-cycle saving and human capital investment in children, responds to rising longevity in a recursive model with altruistic agents. We find that rising longevity raises the retirement age. If initial life expectancy is not too high, rising longevity also raises human capital investment in children and the saving rate. Through these channels, rising longevity can be conducive to long-run economic growth. A binding mandatory retirement age reduces human capital investment and the growth rate, raises the saving rate, and reduces welfare.
TL;DR: A multiobjective optimization framework that tackles the problem of mobile WiMax access network design by using the method of the Pareto front, and the use of an optimization strategy based on a modified version of the metaheuristic Tabu search adapted to multi objective optimization.
Abstract: In this paper, a multiobjective optimization framework that tackles the problem of mobile WiMax access network design is presented. In the first stage of the network development, the most important issue is to find an appropriate solution to the base station location from a given set of candidate sites. The network can be considerably improved if the base station location solution found during the planning phase is designed to achieve optimal performance, and also reliable and cost-effective mobile WiMax networks. The design process is done through computer simulation to predict the network performance, and it is often carried out by planning and optimization tools similar to those used in the development of 2nd generation cellular networks (2G) with a few adaptations. The multiobjective optimization framework gives network providers a new perspective in mobile WiMax access network design, providing a clear and comprehensive description of different options and solutions to achieve an optimal base station location. Also, it analyzes the network performance with the mobile WiMax-specific parameters that most importantly affect the access network design process. It simplifies the problem and translates it into a formal optimization routine with consideration of economic factors in mobile WiMax networks. This has been done by using the method of the Pareto front, and the use of an optimization strategy based on a modified version of the metaheuristic Tabu search adapted to multiobjective optimization.
TL;DR: In this article, 4-Piperazinyl-N -methyl-1,8-naphthalimide (PMN) was synthesized and encapsulated into mesoporous molecular sieves.
TL;DR: In this article, the authors measured the response of the hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c, and applied corrections to the signals from the considerably different electromagnetic (EB) and hadronic (HB) calorimeters in reconstructing the energies of hadrons.
Abstract: The response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c has been measured. To our knowledge, this is the widest range of momenta in which any calorimeter system has been studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. The analysis of the differences in calorimeter response to charged pions, kaons, protons and antiprotons and a detailed discussion of the underlying phenomena are presented. We also show techniques that apply corrections to the signals from the considerably different electromagnetic (EB) and hadronic (HB) barrel calorimeters in reconstructing the energies of hadrons. Above 5 GeV/c, these corrections improve the energy resolution of the combined system where the stochastic term equals 84.7 ±1.6% and the constant term is 7.4 ±0.8%. The corrected mean response remains constant within 1.3 % rms. EPJ manuscript No. (will be inserted by the editor) The CMS Barrel Calorimeter Response to Particle Beams from 2 to 350 GeV/c CMS HCAL/ECAL Collaborations S. Abdullin, V. Abramov, B. Acharya, N. Adam, M. Adams, P. Adzic, N. Akchurin, U. Akgun, E. Albayrak, R. Alemany-Fernandez, N. Almeida, G. Anagnostou, D. Andelin, E. W. Anderson, M. Anfreville, I. Anicin, G. Antchev, Z. Antunovic, R. Arcidiacono, M. W. Arenton, E. Auffray, S. Argiro, A. Askew, O. Atramentov, S. Ayan, M. Arcidy, S. Aydin, T. Aziz, M. Baarmand, K. Babich, S. Baccaro, D. Baden, S. Baffioni, M. N. Bakirci, M. Balazs, Sud. Banerjee, Sun. Banerjee, R. Bard, D. Barge, V. Barnes, D. Barney, L. Barone, A. Bartoloni, C. Baty, H. Bawa, G. Baiatian, D. Bandurin, S. Beauceron, K. W. Bell, G. Bencze, R. Benetta, M. Bercher, S. Beri, C. Bernet, L. Berntzon, U. Berthon, M. Besancon, B. Betev, R. Beuselinck, V. Bhatnagar, A. Bhatti, C. Biino, J. Blaha, P. Bloch, S. Blyth, A. Bodek, A. Bornheim, S. Bose, T. Bose, J. Bourotte, A. M. Brett, R. M. Brown, D. Britton, H. Budd, M. Buehler, K. Burchesky, P. Busson, B. Camanzi, T. Camporesi, K. Cankoçak, K. Carrell, E. Carrera, N. Cartiglia, F. Cavallari, S. Cerci, M. Cerutti, P. Chang, Y. H. Chang, C. Charlot, E. A. Chen, W. T. Chen, Z. Chen, S. Chendvankar, R. Chipaux, B. C. Choudhary, R. K. Choudhury, Y. Chung, W. Clarida, D. J. A. Cockerill, C. Combaret, S. Conetti, F. Cossutti, B. Cox, L. Cremaldi, P. Cushman, D. G. Cussans, I. Dafinei, J. Damgov, D. R. Da Silva Di Calafiori, G. Daskalakis, G. Davatz, A. David, P. de Barbaro, P. Debbins, K. Deiters, M. Dejardin, M. Djordjevic, M. Deliomeroglu, R. Della Negra, G. Della Ricca, D. Del Re, A. Demianov, A. De Min, D. Denegri, P. Depasse, T. de Visser, J. Descamps, P. V. Deshpande, J. Diaz, M. Diemoz, E. Di Marco, L. Dimitrov, G. Dissertori, M. Dittmar, L. Djambazov, L. Dobrzynski, S. Drndarevic, J. E. Duboscq, S. Dugad, I. Dumanoglu, F. Duru, D. Dutta, M. Dzelalija, I. Efthymiopoulos, J. Elias, A. Elliott-Peisert, H. El Mamouni, D. Elvira, I. Emeliantchik, S. Eno, A. Ershov, S. Erturk, S. Esen, E. Eskut, I. Evangelou, D. L. Evans, B. Fabbro, J. L. Faure, J. Fay, A. Fenyvesi, F. Ferri, W. Fisher, P. S. Flower, D. Franci, G. Franzoni, J. Freeman, K. Freudenreich, W. Funk, S. Ganjour, C. Gargiulo, S. Gascon, M. Gataullin, V. Gaultney, H. Gamsizkan, V. Gavrilov, Y. Geerebaert, V. Genchev, F. X. Gentit, D. Gerbaudo, Y. Gershtein, A. Ghezzi, M. D. Ghodgaonkar, J. Gilly, A. Givernaud, S. Gleyzer, S. Gninenko, A. Go, B. Gobbo, N. Godinovic, N. Golubev, I. Golutvin, P. Goncharov, D. Gong, P. Govoni, N. Grant, P. Gras, T. Grassi, D. Green, R. J. S. Greenhalgh, A. Gribushin, B. Grinev, L. Guevara Riveros, J. P. Guillaud, A. Gurtu, A. Murat Güler, E. Gülmez, K. Gümüş, T. Haelen, S. Hagopian, V. Hagopian, M. Haguenauer, V. Halyo, G. Hamel de Monchenault, M. Hansen, M. Hashemi, J. Hauptman, E. Hazen, H. F. Heath, A. Heering, A. Heister, B. Heltsley, J. A. Hill, W. Hintz, R. Hirosky, P. R. Hobson, A. Honma, G. W. S. Hou, Y. Hsiung, A. Hunt, M. Husejko, B. Ille, N. Ilyina, R. Imlay, D. Ingram, Q. Ingram, E. Isiksal, P. Jarry, C. Jarvis, C. Jeong, C. Jessop, K. Johnson, J. Jones, D. Jovanovic, K. Kaadze, V. Kachanov, V. Kaftanov, S. Kailas, V. Kalagin, A. Kalinin, S. Kalmani, D. Karmgard, S. K. Kataria, M. Kaur, M. Kaya, O. Kaya, A. Kayis-Topaksu, R. Kellogg, B. W. Kennedy, A. Khmelnikov, H. Kim, I. Kisselevich, K. Kloukinas, O. Kodolova, J. Kohli, P. Kokkas, T. Kolberg, V. Kolossov, A. Korablev, Y. Korneev, I. Kosarev, L. Kramer, N. Krasnikov, A. Krinitsyn, A. Krokhotin, D. Krpic, V. Kryshkin, Y. Kubota, A. Kubrik, S. Kuleshov, A. Kumar, P. Kumar, S. Kunori, C. M. Kuo, P. Kurt, P. Kyberd, A. Kyriakis, A. Laasanen, V. Ladygin, E. Laird, G. Landsberg, A. Laszlo, C. Lawlor, D. Lazic, M. Lebeau, P. Lecomte, P. Lecoq, A. Ledovskoy, S.-W. Lee, G. Leshev, M. Lethuillier, L. Levchuk, S. W. Lin, W. Lin, S. Linn, A. L. Lintern, V. Litvine, D. Litvintsev, L. Litov, L. Lobolo, E. Locci, A. B. Lodge, E. Longo, D. Loukas, S. Los, V. Lubinsky, P. D. Luckey, V. Lukanin, W. Lustermann, C. Lynch, Y. Ma, E. Machado, H. Mahlke-Krueger, M. Maity, G. Majumder, M. Malberti, J. Malclès, D. Maletic, I. Mandjavidze, J. Mans, N. Manthos, Y. Maravin, C. Marchica, N. Marinelli, A. Markou, C. Markou, D. Marlow, P. Markowitz, M. Marone, G. Martinez, H. Mathez, V. Matveev, C. Mavrommatis, G. Maurelli, K. Mazumdar, P. Meridiani,
TL;DR: Simulation results show that compared with two typical MAC protocols for WSNs, sensor MAC and timeout MAC, G-MAC can increase system throughput, and decrease delay and packet-loss-rate, while maintaining relatively low energy consumption.
Abstract: In the traditional medium access control (MAC) protocols for wireless sensor networks (WSNs), energy consumption is traded for throughput and delay. However, in future WSNs, throughput and delay performance had better not be sacrificed for energy conservation. Here first, an incompletely cooperative game-theoretic heuristic-based constraint optimisation framework is introduced to achieve the goals of throughput, delay and energy conservation simultaneously. Then a simplified game-theoretic MAC (G-MAC) protocol is presented, which can be easily implemented in WSNs. Simulation results show that compared with two typical MAC protocols for WSNs, sensor MAC and timeout MAC, G-MAC can increase system throughput, and decrease delay and packet-loss-rate, while maintaining relatively low energy consumption.
11 Dec 2009
TL;DR: Results show that by this approach, discrete ray launching is suitable for radio wave propagation modelling and significant speedups are observed compared to traditional ray-based models via parallelization techniques such as multi-threading and distributed computing.
Abstract: Ray-based methods such as ray tracing and ray launching have been increasingly used in radio wave propagation modelling. Ray tracing is used for point-to-point multipath prediction (for few receivers) while ray launching, being more adaptable, is more suitable for multi-point prediction. However, ray launching suffers from angular dispersion which causes rays to miss pixels when the distance from the emitter increases. Several solutions such as beam tracing or ray splitting have been proposed to resolve this, but this paper presents a new approach, which is suitable for discrete ray launching, to avoid the problem. Results show that by this approach, discrete ray launching is suitable for radio wave propagation modelling. Significant speedups are observed compared to traditional ray-based models via parallelization techniques such as multi-threading and distributed computing. Complex channel characteristics due to multipaths in the urban environment can be obtained via this method.
Journal Article•
TL;DR: BODE index might have potential to be used as a sensitive tool to assess the status of quality of life and to monitor disease progression among stable COPD patients and is associated with SGRQ score cross-sectionally and longitudinally among stable CopD patients.
Abstract: BACKGROUND The body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index was shown at predicting the risk of death, exacerbation and disease severity among patients with COPD, but few studies verified relationship between BODE index and health related quality of life (HRQoL) among Chinese COPD patients. The objective of this study was to evaluate the relationship between BODE index and HRQoL in cross-sectional and longitudinal association analyses. METHODS A multi-center prospective cohort study was initially conducted in 491 stable COPD patients in Beijing, China. Health status (HRQoL) was assessed by St. George's Respiratory Questionnaire (SGRQ); the BODE index was calculated for each patient; dyspnea was assessed using the 5-grade Medical Research Council dyspnea scale. Other measurements included socio-demographic, body mass index (BMI), lung function test and 6-minute-walk test (6MWT). Patients were then followed monthly for 12 months. RESULTS Only 450 patients completed the 1-year follow up and were enrolled in our present analyses. Mean age was (65.2 +/- 10.6) years, men 309 (68.7%). The BODE index was categorized into 4 subgroups: 0 - 2, 3 - 4, 5 - 6 and 7 - 10. At baseline BODE index was gradually increased with baseline total SGRQ and SGRQ subscales (P trend < 0.001). For individual components of BODE index, with the decrease of airflow limitation, and 6MWD, and with the increase of Medical Research Council (MRC) dyspnea grade, total SGRQ and SGRQ subscales were increased correspondingly, P trend < 0.05, respectively. Similar association patterns were found between baseline BODE index and its individual components and mean SGRQ scores at the end of 1-year follow up. By multiple linear regression analyses, baseline BODE index was not only significantly associated with SGRQ score at baseline but also with SGRQ score at the end of 1-year follow up after adjustment for age, male, current smoking, betas being 0.434 and 0.378, respectively. CONCLUSIONS BODE index is associated with SGRQ score cross-sectionally and longitudinally among stable COPD patients. BODE index might have potential to be used as a sensitive tool to assess the status of quality of life and to monitor disease progression among stable COPD patients.