354 research outputs found
A Robust Quantum Random Access Memory
A "bucket brigade" architecture for a quantum random memory of memory
cells needs times of quantum manipulation on control circuit nodes
per memory call. Here we propose a scheme, in which only average times
manipulation is required to accomplish a memory call. This scheme may
significantly decrease the time spent on a memory call and the average overall
error rate per memory call. A physical implementation scheme for storing an
arbitrary state in a selected memory cell followed by reading it out is
discussed.Comment: 5 pages, 3 figure
Finding Base-Station Locations in Two-Tiered Wireless Sensor Networks by Particle Swarm Optimization
In wireless sensor networks, minimizing power consumption to prolong network lifetime is very crucial. In the past, Pan et al. proposed two algorithms to find the optimal locations of base stations in two-tiered wireless sensor networks. Their approaches assumed the initial energy and the energy-consumption parameters were the same for all application nodes. If any of the above parameters were not the same, their approaches could not work. Recently, the PSO technique has been widely used in finding nearly optimal solutions for optimization problems. In this paper, an algorithm based on particle swarm optimization (PSO) is thus proposed for general power-consumption constraints. The proposed approach can search for nearly optimal BS locations in heterogeneous sensor networks, where application nodes may own different data transmission rates, initial energies and parameter values. Experimental results also show the good performance of the proposed PSO approach and the effects of the parameters on the results. The proposed algorithm can thus help find good BS locations to reduce power consumption and maximize network lifetime in two-tiered wireless sensor networks. Keywords: wireless sensor network, network lifetime, energy consumption, particle swarm optimization, base station
Kerker-Type Positional Disorder Immune Metasurfaces
Metasurfaces that can work without the rigorous periodic arrangement of
meta-atoms are highly desired by practical optical micro-nano devices. In this
work, we proposed two kinds of Kerker-type metasurfaces possessing positional
disorder immunity. The metasurfaces are composed of two different core-shell
cylinders satisfying the first and second Kerker conditions, respectively. Even
with large positional disorder perturbation of the meta-atoms, the metasurfaces
can still maintain the same excellent performances as periodic ones, such as
the total transmission and magnetic mirror responses. This disorder immunity is
due to the unidirectional forward and backward scatterings of a single
core-shell cylinder leading to very weak lateral couplings between neighboring
cylinders thus rarely affecting the multiple scatterings in the forward or
backward direction. In contrast, the dominant response of the disordered
non-Kerker-type metasurface decreases significantly. Our findings provide a new
idea for designing robust metasurfaces and extend the scope of metasurface
applications in sensing and communication under complex practical
circumstances.Comment: 18 pages, 9 figure
THE CORRELATION OF GOLF PUTTING CLUB HEAD VELOCITY AND GRIP FORCE FOR EACH PHASE
We investigate the correlation of golf putting club head velocity and grip force in different phases during the putting stroke. Five elite college players (handicap: 2~8) executed a putt as accurately as possible to reach a target distance of 12ft. The Novel System and were used to measure the grip force and club head velocity. The lowest club head velocity and grip force both occurred at address up to the top of backswing (phase I). The club head velocity and grip force started increasing during the downswing and reached its peak before impact (phase II), and decreased after impact to finish (phase III). The mean club head velocity and grip force for Phase I, II, III in order are 0.33m/s, 0.92m/s, 0.87m/s; 28.09N, 54.77N, 50.76N. Club head velocity was significantly correlated to grip force in phase II and III (r=0.937; r=0.866). The similar variation pattern of club head speed and grip force may give better control to the putter during the impact and produce more consistent putting stroke
Therapeutic protein expression platform of microbial system
A number of expression systems have been developed for the production of pharmaceutical products. Pichia pastoris and Escherichia coli expression system operate in our lab and express antibody fragment (scFv), cytokine, protein base adjuvant and vaccine and process enzyme. The expression platform are consisted of three part, first is strain generation , the second is fermentation process development in 250 ml fermentor and the last is process scale-up to 5 litter fermentor.
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3,5-Dinitrobenzoyl chloride
The carbonyl chloride group in the title compound, C7H3ClN2O5, is disordered over two orientations with occupancies of 0.505 (5) and 0.495 (5). The molecule is approximately planar, the dihedral angle between the carbonyl chloride plane and benzene ring being 9.6 (4)° in the major disorder component and 7.1 (4)° in the minor component. The nitro group at the 5-position is twisted, forming a dihedral angle of 6.7 (4)°. The crystal packing is stabilized by C—H⋯O hydrogen bonds
Gram level scFv expression platform of Phichi pastoris
The methylotrophic yeast Pichia pastoris secretion expression system has been developed for the antibody fragments (scFv) production platform. The platform includes three technology platforms, the first one is strain generation, the second is fermentation process development in 250 ml fermentor and the last is process scale up to 5 L. A recombinant scFv went through clone generation, include signal peptide tool box, normally yield 2.5 mg/L titer in deep well. Through the fermentation process development of induction medium composition and feeding strategy by Eppendorf Dasgip parallel 250 ml mini fermentor. During induction step, feeding 100% methanol as induction medium can only produce less than 50 mg/L scFv while feeding methanol-sorbitol mixture can significant increase the production yield to 306 mg/L in five days, about 6-folds increase in productivity. With the supply of additional nitrogen source during glycerol feeding step or at induction step, higher scFv production with 510 mg/L can be achieved. Thus, following the medium composition optimization, the production titer was improved 10 folds in 250 ml mini-fermentor stage. Moreover, when we switched the induction medium feeding strategy from DO-stat to the stepwise feeding, the titer increased form 510 mg/L to ~1000 mg/L and yielded another 2- folds improvement. During medium composition and feeding strategy optimization at 250 ml mini fermentor scale, the production titer could increase 20 folds. Overall, the production titer increased 400 folds from cell line generation to 250 ml fermentation parameter optimization. Furthermore, the process parameter can be scale-up to 5 L fernentor achieving \u3e 1 g/L. Recent progress to include BIP in the expression vector gave at least 2 fold improvement in scFv titer in shake flask, the new clone will be optimized in our established 250 ml and 5 L fermentation platform
Please click Additional Files below to see the full abstract
Gram Level scFv expression platform of Pichia pastoris
The methylotrophic yeast Pichia pastoris secretion expression system has been developed for the antibody fragments (scFv) production platform. The platform includes three technology platforms, the first one is strain generation, the second is fermentation process development in 250 ml fermentor and the last is process scale up to 5 L. A recombinant scFv went through clone generation, include signal peptide tool box, normally yield 2.5 mg/L titer in deep well. Through the fermentation process development of induction medium composition and feeding strategy by Eppendorf Dasgip parallel 250 ml mini fermentor. During induction step, feeding 100% methanol as induction medium can only produce less than 50 mg/L scFv while feeding methanol-sorbitol mixture can significant increase the production yield to 306 mg/L in five days, about 6-folds increase in productivity. With the supply of additional nitrogen source during glycerol feeding step or at induction step, higher scFv production with 510 mg/L can be achieved. Thus, following the medium composition optimization, the production titer was improved 10 folds in 250 ml mini-fermentor stage. Moreover, when we switched the induction medium feeding strategy from DO-stat to the stepwise feeding, the titer increased form 510 mg/L to ~1000 mg/L and yielded another 2- folds improvement. During medium composition and feeding strategy optimization at 250 ml mini fermentor scale, the production titer could increase 20 folds. Overall, the production titer increased 400 folds from cell line generation to 250 ml fermentation parameter optimization. Furthermore, the process parameter can be scale-up to 5 L fernentor achieving \u3e 1 g/L. Recent progress to include BIP in the expression vector gave at least 2 fold improvement in scFv titer in shake flask, the new clone will be optimized in our established 250 ml and 5 L fermentation platform.
Please click Additional Files below to see the full abstract
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