bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced Load Fan Performance Testing for Input Power Determination
Authors: Nuspl Steven P. , Gerhart Philip M.
Published: May 2009

The ASME Performance Test Code, PTC 11 Fans, is currently undergoing revision. While there are several changes being made, there are also new additions, the most notable of which is a method to measure input power at reduced fan loads. This information is often required to validate a power guarantee; a condition that presents a unique challenge because fan operation needs to be established at a specific flow and pressure rise that can be corrected to guarantee inlet conditions using the fan laws of similarity. Part 1 of this paper outlines a testing procedure to achieve results close to the specified condition. There is a very low probability that any particular test can be performed at the guarantee condition so several tests within acceptable bounds of the specified point are necessary. Part 2 of this paper discusses a multipoint, distance-weighted interpolation method for determining the final result.
Uncertainty Analysis in Fan Testing
Authors: Henry Ray E. , Jorgensen Robert , Gerhart Philip M.
Published: May 2009

The ASME performance test codes require an uncertainty analysis as part of a code test, and some codes require both a pre-test and a post-test uncertainty analysis. ASME PTC-19.1, Test Uncertainty provides the basic approach to conducting an uncertainty analysis. The individual test codes, such as ASME PTC-11, Fans, provide specific guidance for uncertainty analysis of tests of particular equipment or processes. The following issues related to an uncertainty analysis for a PTC-11 fan test are discussed. • Evaluating uncertainties for traverse measurements — Fan testing requires one or more traverses to measure flow rate as well as various pressures, temperatures, and gas composition. Evaluating and propagating the uncertainty associated with traverse point measurements to obtain overall uncertainty is explained. • Evaluating uncertainties for non-traverse measurements — Fan testing also requires the measurement of power input, fan speed, and atmospheric temperature and pressure. Evaluating the uncertainties in these quantities is discussed. • Propagating uncertainties of the measurements into the final results — An analytical method is compared to “dithering” to obtain a sensitivity factor. • Using a pre-test uncertainty analysis to optimize the test design — Examples are provided on how a pre-test uncertainty analysis can be used to reduce the uncertainties of a fan test. The results include results of sample pre-test and post-test uncertainty analyses for fans.
Performance Assessment of Cogeneration Systems in California
Authors: Chittory Kumar , Simons George , Souza Brad
Published: May 2009

Over the past several years, customer-sited cogeneration systems have been viewed as a way to mitigate electrical supply shortages. On the utility side, achieving this goal requires cogeneration systems to operate at a relatively high capacity factor, especially during peak periods. On the customer side, the cogeneration system must be capable of reducing operating costs, which can be accomplished by running the system at high operational efficiency and recovering available waste heat. Our firm has been evaluating customer-sited cogeneration systems installed under the Self Generation Incentive Program (SGIP). This paper will present the results of an in-depth performance evaluation conducted for the SGIP Working Group to evaluate the effectiveness of useful thermal energy recovery of on-site cogeneration systems that received incentives from the program. An earlier study investigated levels of energy efficiency and useful waste heat recovery achieved by cogeneration systems in the SGIP. This study raised some interesting questions regarding the actual operational efficiencies of cogeneration systems and low thermal heat recovery. By incorporating fuel consumption, thermal energy recovery and prime mover performance data obtained through the Program’s measurement and evaluation monitoring efforts, actual measured performance was compared to engineering estimates of performance for each project. Thermal heat recovery plays an important role in the overall performance of a cogeneration system. This paper will explore some of the key drivers behind the unexpectedly low thermal energy recovery and overall plant performance. Possible ways to improve the useful waste heat recovery will also be discussed. Regular maintenance and thorough monitoring of the cogeneration system has big impact on the performance. Because the performance data includes the actual timing (hour and month) of cogeneration system operation, the effects of this distributed generation resource is evaluated by taking into account the large differences between peak and offpeak energy costs and benefits. This program-level distributed generation analysis can help program designers and policy makers to understand the limitations of smaller cogeneration applications relative to those systems envisioned under Public Utility Regulatory Policy Act (PURPA) and thus may have important policy implications for the future of cogeneration and distributed generation programs throughout the U.S.
Maximizing Value of Existing Nuclear Power Plant Generating Assets: A Case Study
Authors: Sunder Raj Komandur S.
Published: May 2009

The nuclear power industry is presently witnessing a renaissance. Global warming, greenhouse effects, concerns with use of as well as rising costs of fossil fuels, the desire to be weaned from foreign oil are all factors driving the need for increased reliance on nuclear power. Consequently, nuclear power plant owners are seeking to maximize the value of their generating assets through various means: improved operation, performance, capacity, availability, reliability and efficiency; license renewals, and; power uprates. Capacity factors are currently averaging well over 90% and, forced outage rates have decreased significantly, reflecting the maturation of operating and maintenance practices. In recognition of low fuel and relatively stable operating costs of their nuclear facilities, nuclear power plant owners have not only applied for license renewals, but have also upgraded the operation and, added electrical generating capacity to the operating units. Using a case study, this paper describes current efforts in maximizing the value of existing nuclear power plant generating assets. The focus of the paper is on maximizing benefits through improved operations and performance.
The Testing of Gas Turbines
Authors: Boyce Meherwan P.
Published: May 2009

ASME codes cover testing of all types of gas turbines between the ASME PTC 22 and ASME PTC 55, which will be available by 2008. The testing of gas turbines in land-based units is handled in PTC 22, while the testing of Aircraft gas turbines is handled in PTC 55. The paper addresses the development of ASME Test Codes, and the testing of gas turbines for aircraft, power generation and mechanical drive gas turbines highlighting some of the many differences in the characteristics of both engines.
Main Steam Line Flow Measurement
Authors: Montgomery Mike , Ifft Stephen A.
Published: May 2009

Increasing energy costs and environmental pressures encourage steam turbine users to find the most economical and efficient operation points for their plant. Main steam flow to the turbine is one of the key measurements to determine turbine efficiency and performance. Conventional inferred mass flow measurements, using pressure readings from the turbine first stage, have inherent inaccuracies and assumptions that often lead to incorrect steam flow readings. If those reading accuracies can be improved, the turbine operator will see many advantages, including improved fuel intake and heat rate measurements, higher turbine efficiency over varying loads, better steam control, and increased power generation. Since fuel contributes almost 50% of the total variable cost of electricity generation, operators are discovering the cost benefit of adding direction main steam line flow measurement. This paper compares and contrasts various techniques for computing steam mass flows in utility boilers and outlines the operational benefits of using real time main steam line flowmeters over inferential steam flow computations. Also, a case study is presented which highlights the operational improvements of direct steam flow measurement.
Lon Protease Is Essential for Paradoxical Survival of
Escherichia coli
Exposed to High Concentrations of Quinolone
Authors: Malik Muhammad , Capecci Joseph , Drlica Karl
Published: May 2009

A deficiency of the
Escherichia coli
Lon protease blocked paradoxical survival occurring at very high nalidixic acid concentrations. The absence of Lon also blocked a parallel increase in cell lysate viscosity likely to reflect DNA size. Thus, Lon may participate in repairing quinolone-mediated DNA lesions formed at high drug concentrations.
Emergence of Quinolone-Resistant
Bordetella pertussis
in Japan
Authors: Ohtsuka Masayuki , Kikuchi Ken , Shimizu Kenichiro , Takahashi Namiko , Ono Yuka , Sasaki Takashi , Hiramatsu Keiichi
Published: May 2009

Six
Bordetella pertussis
strains isolated from children in Japan from 2004 to 2006 showed high-level resistance to nalidixic acid (NAL; MIC, >256 μg/ml) and decreased susceptibilities to fluoroquinolones. All of the NAL-resistant strains had the same D87G mutation in
gyrA
.
Novel Antiviral Agent DTriP-22 Targets RNA-Dependent RNA Polymerase of Enterovirus 71
Authors: Chen Tzu-Chun , Chang Hwan-You , Lin Pei-Fen , Chern Jyh-Haur , Hsu John Tsu-An , Chang Chu-Yi , Shih Shin-Ru
Published: May 2009

Enterovirus 71 (EV71) has emerged as an important virulent neurotropic enterovirus in young children. DTriP-22 (4{4-[(2-bromo-phenyl)-(3-methyl-thiophen-2-yl)-methyl]-piperazin-1-yl}-1-pheny-1
H
-pyrazolo[3,4-
d
]pyrimidine) was found to be a novel and potent inhibitor of EV71. The molecular target of this compound was identified by analyzing DTriP-22-resistant viruses. A substitution of lysine for Arg163 in EV71 3D polymerase rendered the virus drug resistant. DTriP-22 exhibited the ability to inhibit viral replication by reducing viral RNA accumulation. The compound suppressed the accumulated levels of both positive- and negative-stranded viral RNA during virus infection. An in vitro polymerase assay indicated that DTriP-22 inhibited the poly(U) elongation activity, but not the VPg uridylylation activity, of EV71 polymerase. These findings demonstrate that the nonnucleoside analogue DTriP-22 acts as a novel inhibitor of EV71 polymerase. DTriP-22 also exhibited a broad spectrum of antiviral activity against other picornaviruses, which highlights its potential in the development of antiviral agents.
Heteroresistance to Fluconazole in
Cryptococcus neoformans
Is Intrinsic and Associated with Virulence
Authors: Sionov Edward , Chang Yun C. , Garraffo H. Martin , Kwon-Chung Kyung J.
Published: May 2009

In 1999, heteroresistance to triazoles was reported in
Cryptococcus neoformans
strains isolated from an azole therapy failure case of cryptococcosis in an AIDS patient and in a diagnostic strain from a non-AIDS patient. In this study, we analyzed 130 strains of
C. neoformans
isolated from clinical and environmental sources before 1979, prior to the advent of triazoles, and 16 fluconazole (FLC)-resistant strains isolated from AIDS patients undergoing FLC maintenance therapy during 1990 to 2000. All strains isolated prior to 1979 manifested heteroresistance (subset of a population that grows in the presence of FLC) at concentrations between 4 and 64 μg/ml, and all 16 FLC-resistant AIDS isolates manifested heteroresistance at concentrations between 16 and 128 μg/ml. Upon exposure to stepwise increases in the concentration of FLC, subpopulations that could grow at higher concentrations emerged. Repeated transfer on drug-free media caused the highly resistant subpopulations to revert to the original level of heteroresistance. The reversion pattern fell into four categories based on the number of transfers required. The strains heteroresistant at ≥32 μg/ml were significantly more resistant to other xenobiotics and were also more virulent in mice than were those heteroresistant at ≤8 μg/ml. During FLC treatment of mice infected by strains with low levels of heteroresistance, subpopulations exhibiting higher levels of heteroresistance emerged after a certain period of time. The ABC transporter
AFR1
, known to efflux FLC, was unrelated to the heteroresistance mechanism. Our study showed that heteroresistance to azole is universal and suggests that heteroresistance contributes to relapse of cryptococcosis during azole maintenance therapy.
Activity of SQ641, a Capuramycin Analog, in a Murine Model of Tuberculosis
Authors: Nikonenko Boris V. , Reddy Venkata M. , Protopopova Marina , Bogatcheva Elena , Einck Leo , Nacy Carol A.
Published: May 2009

New delivery vehicles and routes of delivery were developed for the capuramycin analogue SQ641. While this compound has remarkable in vitro potency against
Mycobacterium tuberculosis
, it has low solubility in water and poor intracellular activity. We demonstrate here that SQ641 dissolved in the water-soluble vitamin E analogue α-tocopheryl polyethylene glycol 1000 succinate (TPGS) or incorporated into TPGS-micelles has significant activity in a mouse model of tuberculosis.
Activity of Telavancin against
Staphylococcus aureus
Strains with Various Vancomycin Susceptibilities in an In Vitro Pharmacokinetic/Pharmacodynamic Model with Simulated Endocardial Vegetations
Authors: Leonard Steven N. , Vidaillac Céline , Rybak Michael J.
Published: May 2009

We investigated the activity of telavancin, a novel lipoglycopeptide, alone and combined with gentamicin or rifampin (rifampicin) against strains of
Staphylococcus aureus
with various vancomycin susceptibilities. Strains tested included methicillin (meticillin)-resistant
S. aureus
(MRSA) 494, methicillin-sensitive
S. aureus
(MSSA) 1199, heteroresistant glycopeptide-intermediate
S. aureus
(hGISA) 1629, which was confirmed by a population analysis profile, and glycopeptide-intermediate
S. aureus
(GISA) NJ 992. Regimens of 10 mg/kg telavancin daily and 1 g vancomycin every 12 h were investigated alone and combined with 5 mg/kg gentamicin daily or 300 mg rifampin every 8 h in an in vitro model with simulated endocardial vegetations over 96 h. Telavancin demonstrated significantly greater killing than did vancomycin (
P
< 0.01) for all isolates except MRSA 494 (
P
= 0.07). Telavancin absolute reductions, in log
10
CFU/g, at 96 h were 2.8 ± 0.5 for MRSA 494, 2.8 ± 0.3 for MSSA 1199, 4.2 ± 0.2 for hGISA 1629, and 4.1 ± 0.3 for GISA NJ 992. Combinations of telavancin with gentamicin significantly enhanced killing compared to telavancin alone against all isolates (
P
< 0.001) except MRSA 494 (
P
= 0.176). This enhancement was most evident against hGISA 1629, where killing to the level of detection (2 log
10
CFU/g) was achieved at 48 h (
P
< 0.001). The addition of rifampin to telavancin resulted in significant (
P
< 0.001) enhancement of killing against only MSSA 1199. No changes in telavancin susceptibilities were observed. These results suggest that telavancin may have therapeutic potential, especially against strains with reduced susceptibility to vancomycin. Combination therapy, particularly with gentamicin, may improve bacterial killing against certain strains.
Safety and Pharmacokinetics of Chimeric Anti-Shiga Toxin 1 and Anti-Shiga Toxin 2 Monoclonal Antibodies in Healthy Volunteers
Authors: Bitzan Martin , Poole Ruth , Mehran Mariam , Sicard Eric , Brockus Catherine , Thuning-Roberson Claire , Rivière Marc
Published: May 2009

Shiga toxin (Stx)-producing
Escherichia coli
(STEC) causes hemorrhagic colitis and hemolytic-uremic syndrome (HUS). The rates of STEC infection and complications, including death, are highest among young children and elderly individuals. There are no causal therapies. Because Stx is the primary pathological agent leading to organ injury in patients with STEC disease, therapeutic antibodies are being developed to neutralize systemically absorbed toxin during the early phase of the infection. Two phase I, single-dose, open-label, nonrandomized studies were conducted to evaluate the safety and pharmacokinetics of the chimeric monoclonal antibodies (antitoxins) against Stx 1 and 2 (cαStx1 and cαStx2, respectively). In the first study, 16 volunteers received 1 or 3 mg/kg of body weight of cαStx1 or cαStx2 as a single, short (1-h) intravenous infusion (
n
= 4 per group). In a second study, 10 volunteers received a 1-h infusion of cαStx1 and cαStx2 combined at 1 or 3 mg/kg (
n
= 5 per group). Treatment-emergent adverse events were mild, resolved spontaneously, and were generally unrelated to the antibody infusion. No serious adverse events were observed. Human antichimeric antibodies were detected in a single blood sample collected on day 57. Antibody clearance was slightly greater for cαStx1 (0.38 ± 0.16 ml/h/kg [mean ± standard deviation]) than for cαStx2 (0.20 ± 0.07 ml/h/kg) (
P
= 0.0013,
t
test). The low clearance is consistent with the long elimination half-lives of cαStx1 (190.4 ± 140.2 h) and cαStx2 (260.6 ± 112.4 h;
P
= 0.151). The small volume of distribution (0.08 ± 0.05 liter/kg, combined data) indicates that the antibodies are retained within the circulation. The conclusion is that cαStx1 and cαStx2, given as individual or combined short intravenous infusions, are well tolerated. These results form the basis for future safety and efficacy trials with patients with STEC infections to ameliorate or prevent HUS and other complications.
Role for Toll-Like Receptor 2 in the Immune Response toStreptococcus pneumoniaeInfection in Mouse Otitis Media
Authors: Han Fengchan , Yu Heping , Tian Cong , Li Shengli , Jacobs Michael R. , Benedict-Alderfer Cindy , Zheng Qing Y.
Published: May 2009

Streptococcus pneumoniaeis the most common pathogen associated with otitis media. To examine the role of Toll-like receptor 2 (TLR2) in host defense againstStreptococcus pneumoniaeinfection in the middle ear, wild-type (WT; C57BL/6) and TLR2-deficient (TLR2−/−) mice were inoculated withStreptococcus pneumoniae(1 × 106CFU) through the tympanic membrane. Nineteen of 37 TLR2−/−mice showed bacteremia and died within 3 days after the challenge, compared to only 4 of 32 WT mice that died. Of those that survived, more severe hearing loss in the TLR2−/−mice than in the WT mice was indicated by an elevation in auditory-evoked brain stem response thresholds at 3 or 7 days postinoculation. The histological pathology was characterized by effusion and tissue damage in the middle ear, and in the TLR2−/−mice, the outcome of infection became more severe at 7 days. At both 3 and 7 days postchallenge, the TLR2−/−mice had higher blood bacterial titers than the WT mice (P< 0.05), and typical bacteria were identified in the effusion from both ears of both mouse groups by acridine orange staining. Moreover, by 3 days postchallenge, the mRNA accumulation levels of NF-κB, tumor necrosis factor alpha, interleukin 1β, MIP1α, Muc5ac, and Muc5b were significantly lower in the ears of TLR2−/−mice than in WT mice. In summary, TLR2−/−mice may produce relatively low levels of proinflammatory cytokines following pneumococcal challenge, thus hindering the clearance of bacteria from the middle ear and leading to sepsis and a high mortality rate. This study provides evidence that TLR2 is important in the molecular pathogenesis and host response to otitis media.
Insulin U-500 in severe insulin resistance in type 2 diabetes mellitus
Authors: Crasto W , Jarvis J , Hackett E , Nayyar V , McNally P G , Davies M J , Lawrence I G
Published: May 2009

Some patients with type 2 diabetes mellitus (T2DM) are profoundly insulin resistant and require large insulin doses to achieve optimal glycaemic control. However, large volumes of subcutaneous conventional U-100 insulin can cause discomfort at the injection site, resulting in poor concordance with insulin therapy. One therapeutic option is the use of U-500 insulin, thus reducing the insulin volume by 80%. This review will address the practical issues associated with the use of U-500, clinical efficacy and safety aspects of this concentrated insulin, which has an important role in a subgroup of patients with T2DM.
The preliminary development and testing of a global trigger tool to detect error and patient harm in primary-care records
Authors: de Wet C , Bowie P
Published: May 2009

Background

A multi-method strategy has been proposed to understand and improve the safety of primary care. The trigger tool is a relatively new method that has shown promise in American and secondary healthcare settings. It involves the focused review of a random sample of patient records using a series of “triggers” that alert reviewers to potential errors and previously undetected adverse events.

Aim

To develop and test a global trigger tool to detect errors and adverse events in primary-care records.

Method

Trigger tool development was informed by previous research and content validated by expert opinion. The tool was applied by trained reviewers who worked in pairs to conduct focused audits of 100 randomly selected electronic patient records in each of five urban general practices in central Scotland.

Results

Review of 500 records revealed 2251 consultations and 730 triggers. An adverse event was found in 47 records (9.4%), indicating that harm occurred at a rate of one event per 48 consultations. Of these, 27 were judged to be preventable (42%). A further 17 records (3.4%) contained evidence of a potential adverse event. Harm severity was low to moderate for most patients (82.9%). Error and harm rates were higher in those aged ⩾60 years, and most were medication-related (59%).

Conclusions

The trigger tool was successful in identifying undetected patient harm in primary-care records and may be the most reliable method for achieving this. However, the feasibility of its routine application is open to question. The tool may have greater utility as a research rather than an audit technique. Further testing in larger, representative study samples is required.
MANY BODY THEORY FOR QUARTETS, TRIONS, AND PAIRS IN LOW DENSITY MULTI-COMPONENT FERMI-SYSTEMS
Authors: SCHUCK P. , SOGO T. , RÖPKE G.
Published: May 2009

A selfconsistent many body approach for the description of gases with quartets, trions, and pairs is presented. Applications to 3D Fermi systems at low density are discussed.
ALPHA CLUSTERING AND MONOPOLE STRENGTHS IN LIGHT NUCLEI
Authors: YAMADA T. , FUNAKI Y. , HORIUCHI H. , IKEDA K. , TOHSAKI A.
Published: May 2009

Strengths of monopole excitation to cluster states are discussed in light nuclei. They are in general so strong to be comparable to the single particle strength and shares an appreciable portion of the sum rule value, in spite of large difference of the structure between the cluster state and the shell-model-like ground state. We point out that the essential reasons of the large strengths are twofold: One is the fact that the clustering degree of freedom is possessed even in simple shell model wave functions (this fact is indicated by Bayman-Bohr theorem), and the other is due to the ground-state correlation induced by the activation of the cluster degree of freedom originally involved in the ground state. They are demonstrated in the case of 16 O as a typical light nucleus. The present results imply that the measurement of strong monopole transitions or excitations is generally very useful for the study of cluster states.
FOLDING MODEL ANALYSIS AND CLUSTER STRUCTURE OF THE $^{12} {\rm{C(0}}_2^ + )$ STATE
Authors: TAKASHINA MASAAKI
Published: May 2009

We analyze the α inelastic scattering on 12 C by the coupled-channel calculation based on the folding model potential. We show that the ordinary folding model calculation tends to overestimate the [Formula: see text] inelastic angular distribution, and that this discrepancy is not due to the 3α breakup effect. In order to resolve this problem, we propose a folding procedure considering the well-developed 3α cluster structure of [Formula: see text].
SPECTROSCOPIC FACTORS IN 16O AND NUCLEON ASYMMETRY
Authors: BARBIERI C. , DICKHOFF W. H.
Published: May 2009

The self-consistent Green's functions method is employed to study the spectroscopic factors of quasiparticle states around 16,28 O and 40,60 Ca . The Faddeev random phase approximation (FRPA) is used to account for the coupling of particles with collective excitation modes. Results for 16 O are reviewed first. The same approach is applied to isotopes with large proton-neutron asymmetry to estimate its effect on spectroscopic factors. The results, based on the chiral N3LO force, exhibit an asymmetry dependence similar to that observed in heavy-ion knockout experiments but weaker in magnitude.
CLUSTER STRUCTURES IN 28Si
Authors: TANIGUCHI YASUTAKA , KANADA-EN'YO YOSHIKO , KIMURA MASAAKI
Published: May 2009

Positive-parity states of 28 Si are studied with antisymmetrized molecular dynamics and multi-configuration mixing focusing on clustering and deformations. By superposition of wave functions obtained by energy variation imposing constraints on quadrupole deformation parameter β and distance between α and 24 Mg , and 12 C and 16 O clusters, two oblate bands, two prolate bands and developed α-24 Mg band are obtained. It is found that cluster structure components are contained in those bands.
PRESENT STATUS AND FUTURE PROSPECTS OF HYPERNUCLEAR PHYSICS
Authors: TAMURA H.
Published: May 2009

In recent years, great progress has been made in hypernuclear physics through new experimental techniques as well as theoretical development. Precision γ-ray spectroscopy of hypernuclei has revealed fine structure of various light Λ hypernuclei. Introduction of the (π-, K+) reaction has opened a possibility of studying neutron-rich Λ hypernuclei. The J-PARC facility will allow us to accelerate these experimental studies of Λ hypernuclei and extend hypernuclear physics to double strangess nuclear systems.
FORMATION OF DEEPLY-BOUND K-pp STATE IN 3He(IN-FLIGHT K-, n) REACTION SPECTRUM
Authors: KOIKE TAKAHISA , HARADA TORU
Published: May 2009

The formation of a deeply-bound K-pp state by the 3 He (in-flight K-, n) reaction is investigated theoretically in a distorted-wave impulse approximation using the Green's function method. The expected inclusive and semi-exclusive spectra at pK- = 1.0 GeV / c and θn = 0∘ are calculated for the forthcoming J-PARC E15 experiment. We discuss these spectra with some K--"pp" optical potentials, taking into account the energy-dependence of the imaginary part of the potentials by a phase space suppression factor.
TDDFT APPROACH TO PHOTOABSORPTION IN EVEN-EVEN NUCLEI
Authors: NAKATSUKASA TAKASHI , INAKURA TSUNENORI , YABANA KAZUHIRO
Published: May 2009

We describe the principle of the time-dependent density-functional theory (TDDFT), as well as that of the density functional theory for a localized density and for a deformed density profile. The real-time real-space TDDFT is utilized to calculate photoabsorption cross sections for even-even nuclei. Results for prolate and oblate nuclei, 24 Mg and 28 Si , reproduce basic features of experimental data.
DEGENERATING CLUSTERS IN AN UNBOUND REGION OF 12Be
Authors: ITO MAKOTO
Published: May 2009

The generalized two-center cluster model (GTCM), which can treat various single particle configurations in general two center systems, is applied to the light neutron-rich system, 12 Be = α+α+4N. We discuss the change of the neutrons' configuration around two α-cores as a variation of an excitation energy. We found that the covalent, ionic and atomic configurations appear with a prominent degenerating feature above the α+8 He g.s. particle-decay threshold.
A REMARK ON THE DEVELOPMENT OF THE CLUSTER DYNAMICS IN NUCLEAR MANY BODY SYSTEM
Authors: IKEDA KIYOMI
Published: May 2009

We present a brief history of the structure study of 16 O as a typical example in the development of the cluster model theory over 50 years.
EPIDEMIOLOGY MODEL ON SHORTCUT AND SMALL WORLD NETWORKS
Authors: SHANKER O. , HOGG TAD
Published: May 2009

We show that the behavior of an epidemiology model depends sensitively on the shortcut density in the shortcut network. This is consistent with an earlier work on other processes on the shortcut network. We analytically study the reason for the sensitivity. The shortcut network is similar to the small world network, and it has the advantage that the model dependence on the shortcut density can be analytically studied. The model would be relevant to the spread of diseases in human, animal, plant or other populations, to the spread of viruses in computer networks, or to the spread of social contagion in social networks. It would also be relevant in understanding the variations in the load on routers connecting different computer networks, as the network topology gets extended by the addition of new links, and in analyzing the placement of certain special sensors in a sensor network laid out in a non-random way with some shortcut links.
A MODEL FOR CASCADING FAILURES IN COMPLEX NETWORKS WITH A TUNABLE PARAMETER
Authors: WANG JIANWEI , RONG LILI , ZHANG LIANG
Published: May 2009

In this paper, based on the local preferential redistribution rule of the load after removing a node, we propose a cascading model and explore cascading failures on four typical networks, i.e. the BA with scale-free property, the WS small-world network, the NW network and the ER random network. Assume that a failed node leads only to a redistribution of the load passing through it to its neighboring nodes. We find that all networks reach the strongest robustness level against cascading failures in the case of α=1, which is a tunable parameter in our model, where the robustness is quantified by the critical threshold Tc, at which a phase transition occurs from a normal state to collapse. To a constant network size, we further discuss the correlations between the average degree 〈k〉 and Tc, and draw the conclusion that Tc has a negative correlative with 〈k〉, i.e. the bigger the value of 〈k〉, the smaller the critical threshold Tc. These results may be very helpful for real-life networks to avoid cascading-failure-induced disasters.
A HAMILTONIAN FOR THE BOSON–BOSON INTERACTION BASED ON ELASTIC COUPLING THROUGH FLUX LINES
Authors: DOLOCAN VOICU , DOLOCAN ANDREI , DOLOCAN VOICU OCTAVIAN
Published: May 2009

We present a Hamiltonian for the boson–boson interaction, based on elastic coupling through flux lines. This Hamiltonian may be used to study polaritons and plasmons and likewise the cohesive energy in crystals of noble gases. The presented results for crystals of noble gases are in a good agreement with experimental data.
OPTIMAL CONSTRUCTION OF THE CITY VORONOI DIAGRAM
Authors: BAE SANG WON , KIM JAE-HOON , CHWA KYUNG-YONG
Published: May 2009

We address proximity problems in the presence of roads on the L1 plane. More specifically, we present the first optimal algorithm for constructing the city Voronoi diagram. We apply the continuous Dijkstra method to obtain an optimal algorithm for building a shortest path map for a given source, and then it extends to that for the city Voronoi diagram. Moreover, our algorithm can be extended to other generalized situations including metric spaces induced by roads and obstacles together.
RELATIONS BETWEEN TWO COMMON TYPES OF RECTANGULAR TILINGS
Authors: WANG YUSU
Published: May 2009

Partitioning a multi-dimensional data set (array) into rectangular regions subject to some constraints (error measures) is an important problem arising from applications in parallel computing, databases, VLSI design, and so on. In this paper, we consider two most common types of partitioning used in practice: the Arbitrary partitioning and (p × p) partitioning, and study their relationships under three widely used error metrics: Max-Sum, Sum-SVar, and Sum-SLift.
APPROXIMATION ALGORITHMS FOR THE EUCLIDEAN TRAVELING SALESMAN PROBLEM WITH DISCRETE AND CONTINUOUS NEIGHBORHOODS
Authors: ELBASSIONI KHALED , FISHKIN ALEKSEI V. , SITTERS RENÉ
Published: May 2009

In the Euclidean traveling salesman problem with discrete neighborhoods, we are given a set of points P in the plane and a set of n connected regions (neighborhoods), each containing at least one point of P. We seek to find a tour of minimum length which visits at least one point in each region. We give (i) an O(α)-approximation algorithm for the case when the regions are disjoint and α-fat, with possibly varying size; (ii) an O(α3)-approximation algorithm for intersecting α-fat regions with comparable diameters. These results also apply to the case with continuous neighborhoods, where the sought TSP tour can hit each region at any point. We also give (iii) a simple O( log n)-approximation algorithm for continuous non-fat neighborhoods. The most distinguishing features of these algorithms are their simplicity and low running-time complexities.
TOPOLOGY-GUIDED TESSELLATION OF QUADRATIC ElEMENTS
Authors: DILLARD SCOTT E. , NATARAJAN VIJAY , WEBER GUNTHER H. , PASCUCCI VALERIO , HAMANN BERND
Published: May 2009

Topology-based methods have been successfully used for the analysis and visualization of piecewise-linear functions defined on triangle meshes. This paper describes a mechanism for extending these methods to piecewise-quadratic functions defined on triangulations of surfaces. Each triangular patch is tessellated into monotone regions, so that existing algorithms for computing topological representations of piecewise-linear functions may be applied directly to the piecewise-quadratic function. In particular, the tessellation is used for computing the Reeb graph, a topological data structure that provides a succinct representation of level sets of the function.
Factors Affecting Customer Retention Toward Internet Banking in Malaysia
Authors: Ismail Hishamuddin Bin , Panni Mohammad Fateh Ali Khan
Published: May 2009

Information and communication technology (ICT) is not a strange medium anymore in business operation nowadays. Most businesses regardless of their industries try to equip themselves with the development of ICT. Polatoglu and Ekin (2001) viewed Internet banking as very attractive to banks and to consumers who have higher acceptance of new technology. The purpose of the study is to find out the extent of the effect of the customer demographics on the online customer retention of the internet banking services; the extent of the influence of the characteristics of innovation on customer retention of internet banking services. The study revealed that the demographic variables do not have any significant impact on the customer retention of the internet banking services. However, the study found that all the innovative characteristics like relative advantages, compatibility, trialability, observability and complexity are found to have significant association with the customer retention of internet banking services.
Automated Gene-Retrieval System for Biological Information Needs
Authors: Rahal Imad , Wang Baoying , Rahhal Riad
Published: May 2009

In this day and age, conducting a biological experiment is presumably a very expensive procedure largely owing to the highly sophisticated and expensive equipment necessitated by the process. Conceivably, being capable of isolating and focusing on a smaller set of imperative genes or gene products that are of high relevance to the experiment, pathway, or biological system under investigation is very desirable largely owing to the potential savings in experimental costs. In this work, we propose an intelligent information system capable of generating a ranked list of genes and gene products that are most pertinent to a given biological pathway, experiment or system (referred to as a biological context henceforth). We assume that the biological context of interest can be described by various textual query terms and phrases from the biological domain which, in turn, relate to various molecular functions, biological processes and cellular components of genes and their products. Intelligent text-based analyses and mining are utilised for this purpose by using the published literature, in the form of publication abstracts downloaded from PubMed, with the intention of ranking genes and gene products having identified relationships to the specified description terms based on the gene ontology (GO) standard. At this stage, our approach is capable of producing promising results given all surrounding restrictions, one of which is the lack of similar work in the literature. For demonstration purposes, we report experimental results on the molting regulation pathway in Drosophila melanogaster (fruit fly).
ON MODELINGModels of models
Authors: Dubberly Hugh
Published: May 2009

Editor's note:

This forum presents models relevant to interaction design and service design. It describes the models, how they might be used, and why they matter. It also describes the models' origins and contrasts related models.

In its first year, forum articles described models of innovation process, design process (Analysis-Synthesis Bridge), customer experience cycle, learning in design and product development, the trend from a mechanical to a biological frame in design (era analysis), design research types (map), and interaction types (taxonomy).

However, none of the articles presented a model of models. We correct that oversight here.
Hands-on oriented curriculum and laboratory development for embedded system design
Authors: Huang Yu-Lun , Hu Jwu-Sheng
Published: May 2009

As embedded systems are getting popular in industrial product designs, a dedicated teaching laboratory for embedded systems (EST Lab) has been setup for college and graduate students to get familiar with embedded system engineering and researches. In this paper, we present our experiences in embedded system education curriculum and teaching laboratory design carried out in the past few years. Accompanied by a series of courses with hands-on exercises, students can understand the whole picture of embedded systems in a more systematic way. To give students a comprehensive view of embedded systems, the curriculum includes not only embedded hardware architectures and operating systems but also embedded user-level software designs. We select the most popular and available open-source operating system, Linux 2.6, as the primary experimental platform for all laboratory practices. In addition to the course design, several research results derived from this laboratory are also presented in this paper.
Practical experience teaching embedded systems
Authors: Almeida Carlos
Published: May 2009

The area of embedded systems and their interconnection is of utmost importance nowadays. The technological evolution, and widespread use, of small electronic devices with processing and communication capabilities, creates the potential for the development of new applications in several different domains. Areas such as industrial control, automotive, home automation, surveillance systems, sensor networks applied to the monitoring of wild life, environment, or buildings, are examples of such potential and ubiquity.

The importance of this area can not be ignored in an Electrical and Computer Engineering Course. It is important to make students able to master the technologies related to embedded systems, including "hands-on" experience developing and testing real systems, and dealing with specific application environments with low resources and close hard-ware/software interaction.

This paper describes the author's experience teaching a course of embedded systems in an Electrical and Computer Engineering Course.
Fatty Acid–Derived Signals in Plant Defense
Authors: Kachroo Aardra , Kachroo Pradeep
Published: May 2009

Fatty acids (FAs) consist of long hydrophobic, often unbranched chains of hydrocarbons, with hydrophilic carboxylic acid groups at one end. They are an important source of reserve energy and essential components of membrane lipids in all living organisms. In plants, FA metabolic pathways play significant roles in pathogen defense. Historically, FAs were only assigned passive roles in plant defense such as biosynthetic precursors for cuticular components or the phytohormone jasmonic acid. However, recent discoveries demonstrate more direct roles for FAs and their breakdown products in inducing various modes of plant defenses. Both 16- and 18-carbon FAs participate in defense to modulate basal, effector-triggered, and systemic immunity in plants. Studies of FA metabolic mutants also reveal an active signaling role for the cuticle in plant defense. This review summarizes the current knowledge of the involvement of FAs, FA-derived oxylipins, and enzymes catalyzing FA metabolism in plant defense.
Electron Crystallography as a Technique to Study the Structure on Membrane Proteins in a Lipidic Environment
Authors: Raunser Stefan , Walz Thomas
Published: May 2009

The native environment of integral membrane proteins is a lipid bilayer. The structure of a membrane protein is thus ideally studied in a lipidic environment. In the first part of this review we describe some membrane protein structures that revealed the surrounding lipids and provide a brief overview of the techniques that can be used to study membrane proteins in a lipidic environment. In the second part of this review we focus on electron crystallography of two-dimensional crystals as potentially the most suitable technique for such studies. We describe the individual steps involved in the electron crystallographic determination of a membrane protein structure and discuss current challenges that need to be overcome to transform electron crystallography into a technique that can be routinely used to analyze the structure of membrane proteins embedded in a lipid bilayer.
Particle-Tracking Microrheology of Living Cells: Principles and Applications
Authors: Wirtz Denis
Published: May 2009

A multitude of cellular and subcellular processes depend critically on the mechanical deformability of the cytoplasm. We have recently introduced the method of particle-tracking microrheology, which measures the viscoelastic properties of the cytoplasm locally and with high spatiotemporal resolution. Here we establish the basic principles of particle-tracking microrheology, describing the advantages of this approach over more conventional approaches to cell mechanics. We present basic concepts of molecular mechanics and polymer physics relevant to the microrheological response of cells. Particle-tracking microrheology can probe the mechanical properties of live cells in experimentally difficult, yet more physiological, environments, including cells embedded inside a 3D matrix, adherent cells subjected to shear flows, and cells inside a developing embryo. Particle-tracking microrheology can readily reveal the lost ability of diseased cells to resist shear forces.
Imaging Transcription in Living Cells
Authors: Darzacq Xavier , Yao Jie , Larson Daniel R. , Causse Sébastien Z. , Bosanac Lana , de Turris Valeria , Ruda Vera M. , Lionnet Timothee , Zenklusen Daniel , Guglielmi Benjamin , Tjian Robert , Singer Robert H.
Published: May 2009

The advent of new technologies for the imaging of living cells has made it possible to determine the properties of transcription, the kinetics of polymerase movement, the association of transcription factors, and the progression of the polymerase on the gene. We report here the current state of the field and the progress necessary to achieve a more complete understanding of the various steps in transcription. Our Consortium is dedicated to developing and implementing the technology to further this understanding.
Analysis of a large cluster of SLC22 transporter genes, including novel USTs, reveals species-specific amplification of subsets of family members
Authors: Wu Wei , Baker Michael E. , Eraly Satish A. , Bush Kevin T. , Nigam Sanjay K.
Published: May 2009

When the organic anion transporter Oat1 was first identified as NKT (Lopez-Nieto CE, You G, Bush KT, Barros EJ, Beier DR, Nigam SK. J Biol Chem 272: 6471–6478, 1997), it was argued that it, together with Oct1, may be part of a larger subfamily (now known as SLC22) involved in organic ion and xenobiotic transport. The least studied among SLC22 transporters are the so-called unknown substrate transporters ( USTs). Here, five novel genes located in a cluster on mouse chromosome 19, immediately between Slc22a8 ( Oat3)/ Slc22a6 ( Oat1) and Slc22a19 ( Oat5), were identified as homologs of human USTs. These genes display preferential expression in liver and kidney, and one gene, AB056422, has several splicing variants with differential tissue expression and embryonic expression. Along with Slc22a6, Slc22a8, and Slc22a19, these Usts define the largest known cluster of mammalian Slc22 genes. Given the established functions of Oats, these genes may also be involved in organic anion transport. Usts have characteristic motifs and share a signature residue in the possible active site of transmembrane domain 7, a conserved, positively charged, amino acid, Arg356, possibly a site for interaction with organic anions. In certain species, Oat1 and Oat3 appeared to be highly conserved, whereas the Ust part of this cluster appeared to undergo repeated species-specific amplification, suggesting strong environmental selection pressure, and perhaps providing an explanation for copy number variation in the human locus. One Ust amplification in mouse appears to be recent. This cluster may be coordinately regulated and under selective pressure in a species-specific manner.
Growth of Solutions of Nonhomogeneous Linear Differential Equations
Authors: Wang Jun , Laine Ilpo
Published: May 2009

This paper is devoted to studying growth of solutions of linear differential
equations of type f(k) + Ak−1(z)f(k−1) + ⋯+A1(z)f′ + A0(z)f = H(z) where Aj (j = 0, …, k − 1) and H are entire functions of finite order.
Unsupervised Learning of Overlapping Image Components Using Divisive Input Modulation
Authors: Spratling M. W. , De Meyer K. , Kompass R.
Published: May 2009

This paper demonstrates that nonnegative matrix factorisation is mathematically related to a class
of neural networks that employ negative feedback as a mechanism of competition. This observation
inspires a novel learning algorithm which we call Divisive Input Modulation (DIM). The proposed
algorithm provides a mathematically simple and computationally efficient method for the unsupervised
learning of image components, even in conditions where these elementary features overlap
considerably. To test the proposed algorithm, a novel artificial task is introduced which is similar
to the frequently‐used bars problem but employs squares rather than bars to increase the degree of
overlap between components. Using this task, we investigate how the proposed method performs on
the parsing of artificial images composed of overlapping features, given the correct representation
of the individual components; and secondly, we investigate how well it can learn the elementary
components from artificial training images. We compare the performance of the proposed algorithm
with its predecessors including variations on these algorithms that have produced state‐of‐the‐art
performance on the bars problem. The proposed algorithm is more successful than its predecessors
in dealing with overlap and occlusion in the artificial task that has been used to assess performance.