Operator Analysis of L=1 Baryon Masses in Large N_c QCD

We consider in detail the mass operator analysis for the nonstrange L=1 excited baryons in large N_c QCD. We present a straightforward procedure for constructing the large N_c baryon wavefunctions, and provide complete analytic expressions for the matrix elements of all the independent isosinglet mass operators. We discuss the relationship between the old-fashioned operator analyses based on nonrelativistic SU(6) symmetry and the modern large N_c approach, which has a firmer theoretical foundation. We then suggest a possible dynamical interpretation for the subset of operators preferred strongly by the data.Comment: 36 pages LaTe

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

WEB PAGES CLUSTER BASED ON THE RELATIONS OF MAPPING KEYWORDS TO ONTOLOGY CONCEPT HIERARCHY

In this paper, we present a related web page cluster method that not only considers the corresponding domain keywords on ontology but also analyzes semantic contents of web pages. First, the method embeds the corresponding domain ontology of search keyword to find web pages front the Internet. Next, consider the location of the keywords in the web pages, and relations between keywords and concepts in the domain ontology to find the features of the web pages. Then, the web pages were clustered based on the similarity values of mapping keywords concept-ontology level relations. Primary experimental results prove that our method is effective to find related web pages

Fuzzy Longitudinal Controller Design and Experimentation for Adaptive Cruise Control and Stop&Go

This paper presents a fuzzy longitudinal control system with car-following speed ranging from 0 to 120 km/h, thereby achieving the main functions of both adaptive cruise control (ACC) and Stop&Go control. A fuzzy longitudinal controller is synthesized by inputting the difference of the actual relative distance and the safe distance obtained from the preceding vehicle, and the relative speed, and then outputting the pulse-width-modulation (PWM) signal to control the output forces of the vacuum boosters. With the use of the high-level controller from dSPACE, the fuzzy control law is easily and rapidly implemented using Matlab/Simulink for the experimental car, and the controller's parameters can be changed and updated by analyzing data based on the relative distance using Lidar, the speed of the host vehicle, the opening of the throttle and the position of the braking pedal. For the sake of safe driving, experimental results are conducted by simulating the various possible car-following conditions for the ACC and Stop&Go controllers, thereby obtaining virtually relative distances and speeds to tune the controller's parameters and ensure the safety of the controller. Several car following experiments are conducted to show that the proposed fuzzy longitudinal controller is capable of achieving the requirements of comfort and safety, and giving a satisfactory performance at high and low speed conditions

Structure-reactivity probes for active site shapes of cholesterol esterase by carbamate inhibitors

4.4'-Biphenyl-di-N-butylcarbamate (1), (S)-1,1'-bi-2-naphthyl-2,2'-di-N-butylcarbama (S-2), (S)-1,1'-bi-2-naphthyl-2-N-butylcarbamate-2'-butyrate (S-3), 2,2'-biphenyl-di-N-butylcarbamate (4), 2,2'-biphenyl-2-N-octadecylcarbamate-2'-N-octylcarbamate (5), 2,2'-biphenyl-2-N-octadecylcarbamate-2'-N-phenylcarbamate (6), 2,2'-biphenyl-2-N-butylcarbamate-2'-butyrate (7), 2,2'-biphenyl-2-N-butylcarbamate-2'-ol (8), 2,2'-biphnyl-2-N-octylcarbamate-2'-ol (9), (R)-1,1'-bi-2-N-naphthyl-2-butylcarbamate-2'-ol (R-10), and glyceryl-1,2,3-tri-N-butylcarbarnate (11) are prepared and evaluated for their inhibition effects on porcine pancreatic cholesterol esterase. All inhibitors are irreversible inhibitors of the enzyme. Carbamates 1-3 and 7-10 are the first alkyl chain and esteratic binding site-directed irreversible inhibitors due to the fact that the reactivity of the enzyme is protected by the irreversible inhibitor, trifluoroacetophenone in the presence of these carbamates. Carbamate 1 is the least potent inhibitor for the enzyme probably due to the fact that the inhibitor molecule adopts a linear conformation and one of the carbamyl groups of the inhibitor molecule covalently interacts with the first alkyl chain binding site of the enzyme while the other carbamyl group of the inhibitor molecule exposes outside the active site. With near orthogonal conformations at the pivot bond of biaryl groups, one carbamyl group of carbamates S-2, S-3, and R-10 covalently binds to the first alkyl chain binding site of the enzyme while the other carbamyl, butyryl, or hydroxy group can not bind covalently to the second alkyl chain binding site probably due to the orthogonal conformations. Carbamates 4-9 and 11 are very potent inhibitors for the enzyme probably due to the fact that all these molecules freely rotate at the pivot bond of the biphenyl or glyceryl group and therefore can fit well into the bent-shaped first and second alkyl chains binding sites of the enzyme. Although, carbamates 4-6 and 11 are irreversible inhibitors of cholesterol esterase, the enzyme is not protected but further inhibited by trifluoroacetophenone in the presence of these carbamates. Therefore, carbamates 4-6 and 11 covalently bind to the first alkyl chain binding site of the enzyme by one of the carbamyl groups and may also bind to the second alkyl chain binding site of the enzyme by the second carbamyl group. Besides the bent-shaped conformation, the inhibition by carbamate 6 is probably assisted by a favorable pi-pi interaction between Phe 324 at the second alkyl chain binding site of the enzyme and the phenyl group of the inhibitor molecule. For cholesterol esterase, carbamates 8-10 are more potent than carbamates S-2, 4, and 5 probably due to the fact that the inhibitor molecules interact with the second alkyl chain binding site of the enzyme through a hydrogen bond between the phenol hydroxy group of the inhibitor molecules and the His 435 residue in that site. (C) 1999 Published by Elsevier Science B.V. All rights reserved