990 research outputs found
On the Z_p-ranks of tamely ramified Iwasawa modules
For a prime number p, we denote by K the cyclotomic Z_p-extension of a number
field k. For a finite set S of prime numbers, we consider the S-ramified
Iwasawa module which is the Galois group of the maximal abelian pro-p-extension
of K unramified outside S. This paper treats the case where S does not contain
p and k is the rational number field or an imaginary quadratic field. In this
case, we prove the explicit formulae for the free ranks of the S-ramified
Iwasawa modules as abelian pro-p groups, by using Brumer's p-adic version of
Baker's theorem on the linear independence of logarithms of algebraic numbers
Renormalised nonequilibrium quantum field theory: scalar fields
We discuss the renormalisation of the initial value problem in quantum field
theory using the two-particle irreducible (2PI) effective action formalism. The
nonequilibrium dynamics is renormalised by counterterms determined in
equilibrium. We emphasize the importance of the appropriate choice of initial
conditions and go beyond the Gaussian initial density operator by defining
self-consistent initial conditions. We study the corresponding time evolution
and present a numerical example which supports the existence of a continuum
limit for this type of initial conditions.Comment: 18 pages in revtex4, 5 figure
Alien Registration- De Salle, Maria L. (Rumford, Oxford County)
https://digitalmaine.com/alien_docs/12683/thumbnail.jp
Lyapunov Control on Quantum Open System in Decoherence-free Subspaces
A scheme to drive and manipulate a finite-dimensional quantum system in the
decoherence-free subspaces(DFS) by Lyapunov control is proposed. Control fields
are established by Lyapunov function. This proposal can drive the open quantum
system into the DFS and manipulate it to any desired eigenstate of the free
Hamiltonian. An example which consists of a four-level system with three
long-lived states driven by two lasers is presented to exemplify the scheme. We
have performed numerical simulations for the dynamics of the four-level system,
which show that the scheme works good.Comment: 5 pages, 6 figure
Diosgenin, a plant steroid, induces apoptosis in human rheumatoid arthritis synoviocytes with cyclooxygenase-2 overexpression
In the present study, we have shown for the first time that a plant steroid, diosgenin, causes an inhibition of the growth of fibroblast-like synoviocytes from human rheumatoid arthritis, with apoptosis induction associated with cyclooxygenase-2 (COX-2) up-regulation. Celecoxib, a selective COX-2 inhibitor, provoked a large decrease in diosgenin-induced apoptosis even in the presence of exogenous prostaglandin E(2), whereas interleukin-1β, a COX-2 inducer, strongly increased diosgenin-induced apoptosis of these synoviocytes. These findings suggest that the proapoptotic effect of diosgenin is associated with overexpression of COX-2 correlated with overproduction of endogenous prostaglandin E(2). We also observed a loss of mitochondrial membrane potential, caspase-3 activation, and DNA fragmentation after diosgenin treatment
pATsi: Paralogs and singleton genes from Arabidopsis thaliana
Arabidopsis thaliana is widely accepted as a model species in plant
biology. Its genome, due to its small size and diploidy, was the first
to be sequenced among plants, making this species also a reference for
plant comparative genomics. Nevertheless, the evolutionary mechanisms
that shaped the Arabidopsis genome are still controversial. Indeed,
duplications, translocations, inversions, and gene loss events that
contributed to the current organization are difficult to be traced. A
reliable identification of paralogs and single-copy genes is essential
to understand these mechanisms. Therefore, we implemented a dedicated
pipeline to identify paralog genes and classify single-copy genes into
opportune categories. PATsi, a web-accessible database, was organized to
allow the straightforward access to the paralogs organized into networks
and to the classification of single-copy genes. This permits to
efficiently explore the gene collection of Arabidopsis for evolutionary
investigations and comparative genomics
Post-transplant cerebral toxoplasmosis diagnosed by magnetic resonance imaging.
Cerebral toxoplasmosis is a rare late complication in allogeneic bone marrow transplanted patients. Neuroradiological findings may suggest the correct diagnosis. We report a patient in whom cerebral magnetic resonance imaging (MRI) showed a lesion characteristic of toxoplasmosis. Anti- toxoplasma treatment led to clinical and radiological improvement. MRI seems to be a valid tool for detection and follow-up of cerebral toxoplasmosis
An Assessment of Risk of Iodine Deficiency Among Pregnant Women in Sarawak, Malaysia
Previous findings from a state-wide Iodine Deficiency Disorders (IDD) study among pregnant women (PW) in Sarawak indicated that PW are at risk of IDD and further assessment is needed. This paper describes the methodology used in conducting this study for an assessment of risk of iodine deficiency among pregnant women in Sarawak, Malaysia. A total of 30 maternal child health care clinics (MCHCs) were selected using probability proportional to population size (PPS) sampling technique. The PW sample size was calculated based on 95% confidence interval (CI), relative precision of 5%, design effect of 2, anticipated IDD prevalence of 65.0% and non-response rate of 20%. Thus, the total sample size required was 750 (25 respondents per selected MCHC). The WHO Expanded Programme on Immunization (EPI) surveys approach was used to randomly select the first respondent and subsequent respondents were chosen until the required number of PW was met. The required data were obtained through: face-to-face interviews (socio-demographic and food frequency questionnaire), clinical assessments (thyroid size, and hyper/hypothyroidism) and biochemical analysis (urine and blood serum). A total of 677 PW responded in the study with a response rate of 90.2%. Majority of the PW were at second gravida, aged 25-29 years old and of Malay ethnicity. The methodology used in this study was based on International guidelines which may provide state's estimates. All the necessary steps were taken into consideration to ensure valid and reliable findings on current iodine status among PW
Long-Term Fluoride Release from Dental Resins Affects STRO-1+ Cell Behavior.
Fluoride-releasing restorative dental materials can be beneficial to remineralize dentin and help prevent secondary caries. However, the effects of fluoride release from dental materials on the activity of dental pulp stem cells are not known. Here we investigate whether different fluoride release kinetics from dental resins supplemented with modified hydrotalcite (RK-F10) or fluoride-glass filler (RK-FG10) could influence the behavior of a human dental pulp stem cell subpopulation (STRO-1(+) cells) known for its ability to differentiate toward an odontoblast-like phenotype. The 2 resins, characterized by similar physicochemical properties and fluoride content, exhibited different long-term fluoride release kinetics. Our data demonstrate that long-term exposure of STRO-1(+) cells to a continuous release of a low amount of fluoride by RK-F10 increases their migratory response to transforming growth factor β1 (TGF-β1) and stromal cell-derived factor 1 (SDF-1), both important promoters of pulp stem cell recruitment. Moreover, the expression patterns of dentin sialoprotein (dspp), dentin matrix protein 1 (dmp1), osteocalcin (ocn), and matrix extracellular phosphoglycoprotein (mepe) indicate a complete odontoblast-like cell differentiation only when STRO-1(+) cells were cultured on RK-F10. On the contrary, RK-FG10, characterized by an initial fluoride release burst and reduced lifetime of the delivery, did not elicit any significant effect on both STRO-1(+) cell migration and differentiation. Taken together, our results highlight the importance of taking into account fluoride release kinetics in addition to fluoride concentration when designing new fluoride-restorative materials
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