1,863 research outputs found
Interface-induced heavy-hole/light-hole splitting of acceptors in silicon
The energy spectrum of spin-orbit coupled states of individual sub-surface
boron acceptor dopants in silicon have been investigated using scanning
tunneling spectroscopy (STS) at cryogenic temperatures. The spatially resolved
tunnel spectra show two resonances which we ascribe to the heavy- and
light-hole Kramers doublets. This type of broken degeneracy has recently been
argued to be advantageous for the lifetime of acceptor-based qubits [Phys. Rev.
B 88 064308 (2013)]. The depth dependent energy splitting between the heavy-
and light-hole Kramers doublets is consistent with tight binding calculations,
and is in excess of 1 meV for all acceptors within the experimentally
accessible depth range (< 2 nm from the surface). These results will aid the
development of tunable acceptor-based qubits in silicon with long coherence
times and the possibility for electrical manipulation
A Study on Tourism Development Strategy of Kaohsiung City in Taiwan after Urban Style Regeneration
Urban tourism has gradually been emphasized in past years; especially, it is regarded as a savior of urban regeneration in old industrial cities. When losing the competitive advantages and getting declined, old industrial cities are facing the challenge of transformation. The development of urban tourism is considered as the opportunity of industrial cities in dark recession that they start to involve in the development of tourism. Analytic Hierarchy Process (AHP) is applied in this study to evaluate key success factors in the tourism development strategy of Kaohsiung City after the urban style regeneration. AHP is used for confirming the levels of various evaluation factors. The first hierarchy contains four evaluation dimensions, and 14 evaluation standards are covered in the second hierarchy. The results reveal the important sequence of four evaluation factors in the second hierarchy as (1) marketing activity, (2) management strategy, (3) recreational environment, and (4) infrastructure, where the importance of evaluation factors in the third hierarchy is sequenced as (1) urban attraction, (2) environmental facility maintenance, (3) celebrations, (4) local characteristics, and (5) natural landscape. The research results and suggestions in this study are expected to enhance the tourism development of Kaohsiung City in Taiwan after the urban style regeneration.
Keywords: urban style, tourism development strategy, key success factors, Delphi method, AH
Combating Cholera [version 1; peer review: 2 approved]
Cholera infections caused by the gamma-proteobacterium Vibrio cholerae have ravaged human populations for centuries, and cholera pandemics have afflicted every corner of the globe. Fortunately, interventions such as oral rehydration therapy, antibiotics/antimicrobials, and vaccines have saved countless people afflicted with cholera, and new interventions such as probiotics and phage therapy are being developed as promising approaches to treat even more cholera infections. Although current therapies are mostly effective and can reduce disease transmission, cholera outbreaks remain deadly, as was seen during recent outbreaks in Haiti, Ethiopia, and Yemen. This is due to significant underlying political and socioeconomic complications, including shortages of vaccines and clean food and water and a lack of health surveillance. In this review, we highlight the strengths and weaknesses of current cholera therapies, discuss emerging technologies, and argue that a multi-pronged, flexible approach is needed to continue to reduce the worldwide burden of cholera
A new approach to axial coupling constants in the QCD sum rule
We derive new QCD sum rules for the axial coupling constants by considering
two-point correlation functions of the axial-vector currents in a one nucleon
state. The QCD sum rules tell us that the axial coupling constants are
expressed by nucleon matrix elements of quark and gluon operators which are
related to the sigma terms and the moments of parton distribution functions.
The results for the iso-vector axial coupling constants and the 8th component
of the SU(3) octet are in good agreement with experiment.Comment: 10 pages, 1 figure include
Spontaneous Crystallization of Skyrmions and Fractional Vortices in the Fast-rotating and Rapidly-quenched Spin-1 Bose-Einstein Condensates
We investigate the spontaneous generation of crystallized topological defects
via the combining effects of fast rotation and rapid thermal quench on the
spin-1 Bose-Einstein condensates. By solving the stochastic projected
Gross-Pitaevskii equation, we show that, when the system reaches equilibrium, a
hexagonal lattice of skyrmions, and a square lattice of half-quantized vortices
can be formed in a ferromagnetic and antiferromagnetic spinor BEC, respetively,
which can be imaged by using the polarization-dependent phase-contrast method
Bacteraemia caused by Weissella confusa at a university hospital in Taiwan, 1997–2007
AbstractHuman infections caused by Weissella confusa are rarely reported. Ten patients with bacteraemia caused by W. confusa who were treated at a tertiary-care hospital in Taiwan during 1997–2007 were studied. All isolates were initially misidentified as various Lactobacillus and Leuconostoc species by two commercial automated identification methods, and were confirmed to be W. confusa by 16S rRNA sequencing analysis. MICs of these isolates for ten antimicrobial agents were determined by the agar dilution method. The characteristics of these patients included underlying malignancy (n = 4), presence of a central catheter (n = 6), surgery within the previous 3 months (n = 4) and concomitant polymicrobial bacteraemia (n = 5, 50%). Mortality was directly attributed to bacteraemia in two patients. All isolates exhibited high trimethoprim–sulphamethoxazole and ceftazidime MICs (≥128 mg/L) and were inhibited by linezolid, daptomycin, ceftobiprole and tigecycline at 4, 0.12, 2 and 0.12 mg/L, respectively. In conclusion, W. confusa should be included in the list of organisms causing bacteraemia in immunocompromised hosts. Novel antibiotics, including daptomycin, moxifloxacin, doripenem and tigecycline, exert good activity against W. confusa
Impact of measurement backaction on nuclear spin qubits in silicon
Phosphorus donor nuclear spins in silicon couple weakly to the environment
making them promising candidates for high-fidelity qubits. The state of a donor
nuclear spin qubit can be manipulated and read out using its hyperfine
interaction with the electron confined by the donor potential. Here we use a
master equation-based approach to investigate how the backaction from this
electron-mediated measurement affects the lifetimes of single and multi-donor
qubits. We analyze this process as a function of electric and magnetic fields,
and hyperfine interaction strength. Apart from single nuclear spin flips, we
identify an additional measurement-related mechanism, the nuclear spin
flip-flop, which is specific to multi-donor qubits. Although this flip-flop
mechanism reduces qubit lifetimes, we show that it can be effectively
suppressed by the hyperfine Stark shift. We show that using atomic precision
donor placement and engineered Stark shift, we can minimize the measurement
backaction in multi-donor qubits, achieving larger nuclear spin lifetimes than
single donor qubits
Detecting Action Items in Meetings
Abstract. We present a method for detecting action items in spontaneous meeting speech. Using a supervised approach incorporating prosodic, lexical and structural features, we can classify such items with a high degree of accuracy. We also examine how well various feature subclasses can perform this task on their own.
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