905 research outputs found
Effect of Manganese Content on the Fabrication of Porous Anodic Alumina
The influence of manganese content on the formation of well-ordered porous anodic alumina was studied. Porous anodic alumina has been produced on aluminium substrate of different manganese content by single-step anodizing at 50 V in 0.3 M oxalic acid at 15°C for 60 minutes. The well-ordered pore and cell structure was revealed by subjecting the porous anodic alumina to oxide dissolution treatment in a mixture of chromic acid and phosphoric acid. It was found that the manganese content above 1 wt% impaired the regularity of the cell and pore structure significantly, which can be attributed to the presence of secondary phases in the starting material with manganese content above 1 wt%. The pore diameter and interpore distance decreased with the addition of manganese into the substrates. The time variation of current density and the thickness of porous anodic alumina also decreased as a function of the manganese content in the substrates
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Rapid high-dose cyclophosphamide as bridging treatment for advanced therapies in multiple myeloma
Patients with relapsed/refractory multiple myeloma proceeding with chimeric antigen receptor (CAR) T-cell therapy or bispecific antibodies (BsAb) may need bridging therapy to realize their benefits. We evaluated the efficacy and safety of rapid, peripheral, high-dose cyclophosphamide (TurboCy) in 15 patients intending to proceed with CAR T-cell therapy, BsAbs, or long-term regimens. The overall response rate was 80% and the clinical benefit rate was 100% in a heavily pretreated high-risk cohort. Cytopenias were common but no deaths occurred during bridging. All patients proceeded to their next line of intended therapy. TurboCy is an effective and safe bridging strategy
Evaluating the fabric performance and antibacterial properties of 3-D piezoelectric spacer fabric
The increasing need of on-demand power for enabling portable low-power devices and sensors has necessitated work in novel energy harvesting materials and devices. In a recent work, we demonstrated the production and suitability of three-dimensional (3-D) spacer all fibre piezoelectric textiles for converting mechanical energy into electrical energy for wearable and technical applications. The current work investigates the textile performance properties of these 3-D piezoelectric fabrics including porosity, air permeability, water vapour transmission and bursting strength. Furthermore, as these textiles are intended for wearable applications, we have assessed their wear abrasion and consequently provide surface resistance measurements which can affect the lifetime and efficiency of charge collection in the piezoelectric textile structures. The results show that the novel smart fabric with a measured porosity of 68% had good air (1855 l/m2/s) and water vapour permeability (1.34 g/m2/day) values, good wear abrasion resistance over 60,000 rotations applied by a load of 12 kPa and bursting strength higher than 2400 kPa. Moreover, the antibacterial activity of 3-D piezoelectric fabrics revealed that owing to the use of Ag/PA66 yarns, the textiles exhibit excellent antibacterial activity against not only Gram-negative bacteria E. coli but they are also capable of killing antibiotic methicillin-resistant bacteria S. aureus
Transit Timing Analysis in the HAT-P-32 System
We present the results of 45 transit observations obtained for the transiting exoplanet HATP- 32b. The transits have been observed using several telescopes mainly throughout the YETI (Young Exoplanet Transit Initiative) network. In 25 cases, complete transit light curves with a timing precision better than 1.4 min have been obtained. These light curves have been used to refine the system properties, namely inclination i, planet-to-star radius ratio Rp/Rs, and the ratio between the semimajor axis and the stellar radius a/Rs. First analyses by Hartman et al. suggests the existence of a second planet in the system, thus we tried to find an additional body using the transit timing variation (TTV) technique. Taking also the literature data points into account, we can explain all mid-transit times by refining the linear ephemeris by 21 ms. Thus, we can exclude TTV amplitudes of more than ∼1.5min
Generalized pricing formulas for stochastic volatility jump diffusion models applied to the exponential Vasicek model
Path integral techniques for the pricing of financial options are mostly
based on models that can be recast in terms of a Fokker-Planck differential
equation and that, consequently, neglect jumps and only describe drift and
diffusion. We present a method to adapt formulas for both the path-integral
propagators and the option prices themselves, so that jump processes are taken
into account in conjunction with the usual drift and diffusion terms. In
particular, we focus on stochastic volatility models, such as the exponential
Vasicek model, and extend the pricing formulas and propagator of this model to
incorporate jump diffusion with a given jump size distribution. This model is
of importance to include non-Gaussian fluctuations beyond the Black-Scholes
model, and moreover yields a lognormal distribution of the volatilities, in
agreement with results from superstatistical analysis. The results obtained in
the present formalism are checked with Monte Carlo simulations.Comment: 9 pages, 2 figures, 1 tabl
A_4 Symmetry and Lepton Masses and Mixing
Stimulated by Ma's idea which explains the tribimaximal neutrino mixing by
assuming an A_4 flavor symmetry, a lepton mass matrix model is investigated. A
Frogatt-Nielsen type model is assumed, and the flavor structures of the masses
and mixing are caused by the VEVs of SU(2)_L-singlet scalars \phi_i^u and
\phi_i^d (i=1,2,3), which are assigned to {\bf 3} and ({\bf 1}, {\bf 1}',{\bf
1}'') of A_4, respectively.Comment: 13 pages including 1 table, errors in Sec.7 correcte
Model for Particle Masses, Flavor Mixing, and CP Violation Based on Spontaneously Broken Discrete Chiral Symmetry as the Origin of Families
We construct extensions of the standard model based on the hypothesis that
the Higgs bosons also exhibit a family structure, and that the flavor weak
eigenstates in the three families are distinguished by a discrete chiral
symmetry that is spontaneously broken by the Higgs sector. We study in detail
at the tree level models with three Higgs doublets, and with six Higgs doublets
comprising two weakly coupled sets of three. In a leading approximation of
cyclic permutation symmetry the three Higgs model gives a ``democratic''
mass matrix of rank one, while the six Higgs model gives either a rank one mass
matrix, or in the case when it spontaneously violates CP, a rank two mass
matrix corresponding to nonzero second family masses. In both models, the CKM
matrix is exactly unity in leading approximation. Allowing small explicit
violations of cyclic permutation symmetry generates small first family masses
in the six Higgs model, and first and second family masses in the three Higgs
model, and gives a non-trivial CKM matrix in which the mixings of the first and
second family quarks are naturally larger than mixings involving the third
family. Complete numerical fits are given for both models, flavor changing
neutral current constraints are discussed in detail, and the issues of
unification of couplings and neutrino masses are addressed. On a technical
level, our analysis uses the theory of circulant and retrocirculant matrices,
the relevant parts of which are reviewed.Comment: Revtex, 59 pages including four tables at en
An FPTAS for Stochastic Unbounded Min-Knapsack Problem
In this paper, we study the stochastic unbounded min-knapsack problem
(). The ordinary unbounded min-knapsack problem states that:
There are types of items, and there is an infinite number of items of each
type. The items of the same type have the same cost and weight. We want to
choose a set of items such that the total weight is at least and the total
cost is minimized. The \prob~generalizes the ordinary unbounded min-knapsack
problem to the stochastic setting, where the weight of each item is a random
variable following a known distribution and the items of the same type follow
the same weight distribution. In \prob, different types of items may have
different cost and weight distributions. In this paper, we provide an FPTAS for
, i.e., the approximate value our algorithm computes is at
most times the optimum, and our algorithm runs in
time.Comment: 24 page
Seesaw Mass Matrix Model of Quarks and Leptons with Flavor-Triplet Higgs Scalars
In a seesaw mass matrix model M_f = m_L M_F^{-1} m_R^\dagger with a universal
structure of m_L \propto m_R, as the origin of m_L (m_R) for quarks and eptons,
flavor-triplet Higgs scalars whose vacuum expectation values v_i are
proportional to the square roots of the charged lepton masses m_{ei}, i.e. v_i
\propto \sqrt{m_{ei}}, are assumed. Then, it is investigated whether such a
model can explain the observed neutrino masses and mixings (and also quark
masses and mixings) or not.Comment: version accepted by EPJ
Absolute properties of the binary system BB Pegasi
We present a ground based photometry of the low-temperature contact binary BB
Peg. We collected all times of mid-eclipses available in literature and
combined them with those obtained in this study. Analyses of the data indicate
a period increase of 3.0(1) x 10^{-8} days/yr. This period increase of BB Peg
can be interpreted in terms of the mass transfer 2.4 x 10^{-8} Ms yr^{-1} from
the less massive to the more massive component. The physical parameters have
been determined as Mc = 1.42 Ms, Mh = 0.53 Ms, Rc = 1.29 Rs, Rh = 0.83 Rs, Lc =
1.86 Ls, and Lh = 0.94 Ls through simultaneous solution of light and of the
radial velocity curves. The orbital parameters of the third body, that orbits
the contact system in an eccentric orbit, were obtained from the period
variation analysis. The system is compared to the similar binaries in the
Hertzsprung-Russell and Mass-Radius diagram.Comment: 17 pages, 3 figures, accepted for Astronomical Journa
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