1,334 research outputs found
Radiative Tau Lepton Pair Production as a Probe of Anomalous Electromagnetic Couplings of the Tau
We calculate the squared matrix element for the process e+ e- --> tau+ tau-
gamma allowing for anomalous magnetic and electric dipole moments at the tau
tau gamma vertex. No interferences are neglected and no approximations of light
fermion masses are made. We show that anomalous moments affect not only the
cross section, but also the shape of the photon energy and angular
distributions. We also demonstrate that in the case of the anomalous magnetic
dipole moment, the contribution from interference involving Standard Model and
anomalous amplitudes is significant compared to the contribution from anomalous
amplitudes alone. A program to perform the calculation is available and it may
be employed as a Monte Carlo generator.Comment: 14 pages, 8 figures submitted to Nuclear Physics
Utilizing a Meso Scale Limited Dome Test to Study the Effect of Strain Rate on the Formability of Commercial Pure Titanium Grade Two Foil
Due to its hexagonal close-packed (HCP) crystal structures and limited slipping systems, commercial pure titanium (CP Ti) has a relatively low ductility at room temperature. In order to understand the effect of strain rate on formability of the as-received tempered CP Ti grade 2 foils with thickness of 38µm, a series of meso-limited dome height (meso-LDH) tests were designed and conducted at three punch speeds (0.01mm/sec, 12m/sec and 17m/sec) without lubricant at room temperature. The forming limit curves of the foil at three different punch speeds were obtained, and can be used right away for product design, process design and development, die design, and simulations etc. As discovered in this experimental study, the reasons why increasing strain rate can improve the formability are: n value increases with increasing strain rate, the temperature of part increases rapidly due to adiabatic effect, and the negative influence of friction can be reduced
THE SELF-LEADERSHIP AND EMPLOYMENT CONNECTION WITH JOB RESOURCES AS MEDIATOR WITHIN ITS IMPACT TOWARD PROACTIVE BEHAVIOUR
The study aims to examine the influence of self leadership on job resources which consist of skill variety, autonomy, and developmental opportunities, and the influence of job resources on work engagement, and the influence of work engagement on proactive behaviour. The research respondents were 57 employees of PT. Sayap Mas Utama Depo Bogor. To test the proposed hypothesis, SEM PLS analysis are used. The results show that self leadership have significant positive effect on job resources which consist of skill variety, autonomy, and developmental opportunities, and job resources have a significant positive effect on work engagement. Work engagement also shows a significant positive effect on proactive behaviour
Phase diagram for morphological transitions of wetting films on chemically structured substrates
Using an interface displacement model we calculate the shapes of thin
liquidlike films adsorbed on flat substrates containing a chemical stripe. We
determine the entire phase diagram of morphological phase transitions in these
films as function of temperature, undersaturation, and stripe widthComment: 15 pages, RevTeX, 7 Figure
The Significance of the -Numerical Range and the Local -Numerical Range in Quantum Control and Quantum Information
This paper shows how C-numerical-range related new strucures may arise from
practical problems in quantum control--and vice versa, how an understanding of
these structures helps to tackle hot topics in quantum information.
We start out with an overview on the role of C-numerical ranges in current
research problems in quantum theory: the quantum mechanical task of maximising
the projection of a point on the unitary orbit of an initial state onto a
target state C relates to the C-numerical radius of A via maximising the trace
function |\tr \{C^\dagger UAU^\dagger\}|. In quantum control of n qubits one
may be interested (i) in having U\in SU(2^n) for the entire dynamics, or (ii)
in restricting the dynamics to {\em local} operations on each qubit, i.e. to
the n-fold tensor product SU(2)\otimes SU(2)\otimes >...\otimes SU(2).
Interestingly, the latter then leads to a novel entity, the {\em local}
C-numerical range W_{\rm loc}(C,A), whose intricate geometry is neither
star-shaped nor simply connected in contrast to the conventional C-numerical
range. This is shown in the accompanying paper (math-ph/0702005).
We present novel applications of the C-numerical range in quantum control
assisted by gradient flows on the local unitary group: (1) they serve as
powerful tools for deciding whether a quantum interaction can be inverted in
time (in a sense generalising Hahn's famous spin echo); (2) they allow for
optimising witnesses of quantum entanglement. We conclude by relating the
relative C-numerical range to problems of constrained quantum optimisation, for
which we also give Lagrange-type gradient flow algorithms.Comment: update relating to math-ph/070200
Wurtzite Effects on Spin Splitting of GaN/AlN Quantum Wells
A new mechanism (DeltaC1-DeltaC3 coupling) is accounted for the spin
splitting of wurtzite GaN, which is originated from the intrinsic wurtzite
effects (band folding and structure inversion asymmetry). The band-folding
effect generates two conduction bands (DeltaC1 and DeltaC3), in which p-wave
probability has tremendous change when kz approaches anti-crossing zone. The
spin-splitting energy induced by the DeltaC1-DeltaC3 coupling and wurtzite
structure inversion asymmetry is much larger than that evaluated by traditional
Rashba or Dresselhaus effects. When we apply the coupling to GaN/AlN quantum
wells, we find that the spin-splitting energy is sensitively controllable by an
electric field. Based on the mechanism, we proposed a p-wave-enhanced
spin-polarized field effect transistor, made of InxGa1-xN/InyAl1-yN, for
spintronics application.Comment: 12 pages, 4 figures (total 16 pages
Electrochemical detection of low-copy number salivary RNA based on specific signal amplification with a hairpin probe
We developed a technique for electrochemical detection of salivary mRNA employing a hairpin probe (HP). Steric hindrance (SH) suppresses unspecific signal and generates a signal-on amplification process for target detection. The stem-loop configuration brings the reporter end of the probe into close proximity with the surface and makes it unavailable for binding with the mediator. Target binding opens the hairpin structure of the probe, and the mediator can then bind to the accessible reporter. Horseradish peroxidase is utilized to generate electrochemical signal. This signal-on process is characterized by a low basal signal, a strong positive readout and a large dynamic range. The SH is controlled via hairpin design and electrical field. By applying electric field control to HPs, the limit of detection of RNA is about 0.4 fM, which is 10 000-fold more sensitive than conventional linear probes. Endogenous Interleukin-8 mRNA is detected with the HP, and good correlation with the quantitative PCR technique is obtained. The resultant process allows a simple setup and by reducing the number of steps it is suited for the point-of-care detection of specific nucleic acid sequences from complex body fluids such as saliva
Anomalous k-dependent spin splitting in wurtzite AlxGa1-xN/GaN heterostructures
We have confirmed the k-dependent spin splitting in wurtzite AlxGa1-xN/GaN
heterostructures. Anomalous beating pattern in Shubnikov-de Haas measurements
arises from the interference of Rashba and Dresselhaus spin-orbit interactions.
The dominant mechanism for the k-dependent spin splitting at high values of k
is attributed to Dresselhaus term which is enhanced by the Delta C1-Delta C3
coupling of wurtzite band folding effect
Editorial: Observational studies in ADHD: the effects of switching to modified-release methylphenidate preparations on clinical outcomes and adherence
Patients with ADHD may have better adherence to treatment with modified-release methylphenidate (MPH-MR) formulations, which are taken once daily, compared with immediate-release (IR) formulations, which need to be taken several times a day. Data on long-term outcomes such as adherence may be lacking from randomised controlled trials as these are usually only short-term. Observational studies, if performed and reported appropriately, can provide valuable long-term data on such outcomes, as well as additional information on effectiveness and efficiency, from a real-life setting. By reviewing previous observational studies that have investigated switching treatment from MPH-IR to MPH-MR, results from a new, naturalistic observational study, the OBSEER study, are put into context. We conclude that, based on observational trial data, switching from MPH-IR to MPH-MR is a valid clinical approach, with the potential for improved clinical outcome and treatment adherence
Tool Support for Design Science Research—Towards a Software Ecosystem: A Report from a DESRIST 2017 Workshop
The information systems (IS) field contains a rich body of knowledge on approaches, methods, and frameworks that supports researchers in conducting design science research (DSR). It also contains some consensus about the key elements of DSR projects—such as problem identification, design, implementation, evaluation, and abstraction of design knowledge. Still, we lack any commonly accepted tools that address the needs of DSR scholars who seek to structure, manage, and present their projects. Indeed, DSR endeavors, which are often complex and multi-faceted in nature and involve various stakeholders (e.g., researchers, developers, practitioners, and others), require the support that such tools provide. Thus, to investigate the tools that DSR scholars actually need to effectively and efficiently perform their work, we conducted an open workshop with DSR scholars at the 2017 DESRIST conference in Karlsruhe, Germany, to debate 1) the general requirement categories of DSR tool support and 2) the more specific requirements. This paper reports on the results from this workshop. Specifically, we identify nine categories of requirements that fall into the three broad phases (pre-design, design, and post design) and that contribute to a software ecosystem for supporting DSR endeavors
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