Extra unit-speed machines are almost as powerful as speedy machines for flow time scheduling

We study online scheduling of jobs to minimize the flow time and stretch on parallel machines. We consider algorithms that are given extra resources so as to compensate for the lack of future information. Recent results show that a modest increase in machine speed can provide very competitive performance; in particular, using O(1) times faster machines, the algorithm SRPT (shortest remaining processing time) is 1-competitive for both flow time [C. A. Phillips et al., in Proceedings of STOC, ACM, New York, 1997, pp. 140-149] and stretch [W. T. Chan et al., in Proceedings of MFCS, Springer-Verlag, Berlin, 2005, pp. 236-247] and HDF (highest density first) is O(1)-competitive for weighted flow time [L. Becchetti et al., in Proceedings of RANDOM-APPROX, Springer-Verlag, Berlin, 2001, pp. 36-47]. Using extra unit-speed machines instead of faster machines to achieve competitive performance is more challenging, as a faster machine can speed up a job but extra unit-speed machines cannot. This paper gives a nontrivial relationship between the extra-speed and extra-machine analyses. It shows that competitive results via faster machines can be transformed to similar results via extra machines, hence giving the first algorithms that, using O(1) times unit-speed machines, are 1-competitive for flow time and stretch and O(1)-competitive for weighted flow time. © 2008 Society for Industrial and Applied Mathematics.published_or_final_versio

Photoelectrocatalytic oxidation of rhodamine B in aqueous solution using Ti/TiO?mesh photoelectrodes

Author name used in this publication: X. Z. LiAuthor name used in this publication: F. B. LiAuthor name used in this publication: C. L. Mak2001-2002 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Frequency-Reconfigurable Antenna using Metasurface

A frequency-reconfigurable antenna designed using metasurface (MS) to operate at around 5 GHz is proposed and studied. The frequency-reconfigurable metasurfaced (FRMS) antenna is composed of a simple circular patch antenna and a circular MS with the same diameter of 40 mm (0.67 λ) and implemented using planar technology. The MS is placed directly atop the patch antenna, making the FRMS antenna very compact and low profile with a thickness of only 3.048 mm (0.05 λ). The MS consists of rectangular-loop unit cells placed periodically in the vertical and horizontal directions. Simulation results show that the operating frequency of the antenna can be tuned by physically rotating the MS around the center with respect to the patch antenna. The MS placed atop the patch antenna behaves like a dielectric substrate and rotating the MS changes the equivalent relative permittivity of the substrate and hence the operating frequency of the FRMS antenna. Measured results show that the antenna has a tuning range from 4.76 to 5.51 GHz, a fractional tuning range of 14.6%, radiation efficiency and a realized peak gain of more than 80% and 5 dBi, respectively, across the tuning range. © 2013 IEEE.published_or_final_versio

Genetic transformation of Physcomitrella patens mediated by Agrobacterium tumefaciens

A simple efficient protocol for introducing exogenous gene from Agrobacterium tumfaciens into Physcomitrella patens was established. When the gametophores of gametophytes about 12 leaves wereinoculated into the wells of PP3 medium at 25°C under the continuous light energy of 30 mol m-2 s-1 from cool-white fluorescent lamps, they grew up to form many buds at about 11 days, then A. tumefaciens at OD600 0.3 was added into the whole wells for 4 times at an interval of 12 h for continuous co-cultivation. After about 17 days of co-culture, the new juvenile gametophytes about 12 leaves grew up and were incubated into PP3 medium containing 50 mg L-1 kanamycin for selection. 100% positiveplants could be obtained after 4 generations of selective culture. PCR analysis showed that gene Cameleon YC2.1 in A. tumefaciens was transferred into all detected plants of P. patens and southern blotting analysis confirmed that exogenous gene was integrated into genomic DNA at a single locus. The results facilitated to analyze genes from more plants via genetic transformation by this system

A RAMP marker linked to the tobacco black shank resistant gene

Bulk segregant analysis (BSA) and randomly amplified microsatellite polymorphism (RAMP) were employed to analyze F2 individuals of the Yunyan 317×Hubei 517 to screen and characterize molecularmarkers linked to black shank resistant gene. A total of 800 arbitrary decamer oligonucleotide primerpairs were used for RAMP analysis. Primer pair GT (CA) 4/S89, producing one RAMP marker GT (CA)4/S89550, was tightly linked to the black shank resistant gene. Results of Southern blot suggest that the fragment GT (CA) 4/S89550 was existed in Yunyan 317 and resistant plants, and absent in Hubei 517.Linkage analysis was carried out using marker GT (CA) 4/S89550 on 752 black shank high-resistant individuals of F2 progenies from crossing between Yunyan 317 and Hubei 517. Our results indicated thatthe genetic distances between GT (CA) 4/S89550 and black shank resistant gene was 1.4cM

Public knowledge of how to use an automatic external defibrillator in out-of-hospital cardiac arrest in Hong Kong

published_or_final_versio

MT1-MMP cleaves Dll1 to negatively regulate Notch signalling to maintain normal B-cell development

Notch signalling controls the differentiation of haematopoietic progenitor cells (HPCs). Here, we show that loss of membrane-type 1 matrix metalloproteinase (MT1-MMP, MMP14), a cell surface protease expressed in bone marrow stromal cells (BMSCs), increases Notch signalling in HPCs and specifically impairs B-lymphocyte development. When co-cultured with BMSCs in vitro, HPCs differentiation towards B lymphocytes is significantly compromised on MT1-MMP-deficient BMSCs and this defect could be completely rescued by DAPT, a specific Notch signalling inhibitor. The defective B-lymphocyte development could also be largely rescued by DAPT in vivo. MT1-MMP interacts with Notch ligand Delta-like 1 (Dll1) and promotes its cleavage on cell surface in BMSCs. Ectopic MT1-MMP cleaves Dll1 and results in diminished Notch signalling in co-cultured cells. In addition, recombinant MT1-MMP cleaves a synthetic Dll1 peptide at the same site where MT1-MMP cleaves Dll1 on the cell surface. Our data suggest that MT1-MMP directly cleaves Dll1 on BMSCs to negatively regulate Notch signalling to specifically maintain normal B-cell development in bone marrow. © 2011 European Molecular Biology Organization.postprin

Comparison of hydrogen port injection and direct injection (DI) in a single-cylinder dual-fuel diesel engine

Hydrogen direct injection (DI) in a dual-fuel diesel engine is a new technology that can resolve two major issues of its port injection counterpart - knocking and NOx emissions. Compared to widely studied hydrogen port injection in a diesel engine, the hydrogen DI concept executes a near top-dead centre (TDC) injection to cause hydrogen mixing-controlled combustion. The slower burning rate is expected to hinder a rapid pressure rise and subsequent pressure ringing (i.e. knocking) and to reduce NOx emissions, which are problematic in premixed combustion dominant, hydrogen port injection dual-fuel diesel engines. This study directly compares the in-cylinder pressure, efficiency and engine-out emissions of port injected and direct injected hydrogen-diesel dual-fuel combustion in the same engine. The tests were performed in a single-cylinder engine equipped with three injection systems including a hydrogen port injector, a hydrogen direct injector and a common-rail diesel direct injector. The engine was operated at intermediate load using a fixed total energy input of 820 J with hydrogen energy fraction of 50%. The results show that mixing-controlled combustion of the hydrogen in direct injection mode leads to lower in-cylinder pressure and thus lower engine efficiency. However, the severe pressure ringing observed for the hydrogen port injection is avoided and engine-out NOx emission is reduced, indicating the hydrogen DI operation is more stable, its combustion is cleaner and a higher hydrogen utilisation can be achieved

Psychological and demographic factors affecting household energy-saving intentions: A TPB-based study in northwest China

Changing energy consumption behavior is a promising strategy to enhance household energy efficiency and to reduce carbon emission. Understanding the role of psychological and demographic factors in the context of energy-conservation behaviors is critical to promote energy-saving behaviors in buildings. This study first proposes a theoretical framework built on the Theory of Planned Behavior (TPB). Based on the collected survey data from 207 families (553 residents) in three communities in Xi’an, a typical city in northwest China, the research examines how three standard TPB predictors, namely attitude, subjective norm, and perceived behavioral control, as well as their interactive effects and three socio-demographic factors (i.e., house ownership, education and household income) influence building occupants’ energy-saving intention at home. Through structural equation modeling and keyword analysis, this study reveals that two interaction terms, namely attitude and subjective norms, as well as attitude and perceived behavior control, significantly influence building occupants’ energy-saving intention. Furthermore, this study implies that household income may positively associate with occupants’ energy-saving intention. The model in this study would be conducive to architects and property managers to mitigate severe building energy overuse problem in design and operation stages. Based on a qualitative analysis, the study then discusses the limitations of the study and further research direction. The results of this study would be conducive to building designers and operators to develop customized architectural or informatic interventions and to mitigate the severe energy overuse problem in the residential sector in northwest China.</jats:p