531 research outputs found
Statics and Dynamics of an Interface in a Temperature Gradient
The response and nonconserved dynamics of a two-phase interface in the
presence of a temperature gradient oriented normally to the interface are
considered. Two types of boundary conditions on the order parameter are
considered, and the structure of the effective free energy and the Langevin
equation for the collective coordinate specifying the interface position are
analyzed.Comment: 15 pages, Revtex 3.0, 5 figures available upon reques
Direct Integration and Non-Perturbative Effects in Matrix Models
We show how direct integration can be used to solve the closed amplitudes of
multi-cut matrix models with polynomial potentials. In the case of the cubic
matrix model, we give explicit expressions for the ring of non-holomorphic
modular objects that are needed to express all closed matrix model amplitudes.
This allows us to integrate the holomorphic anomaly equation up to holomorphic
modular terms that we fix by the gap condition up to genus four. There is an
one-dimensional submanifold of the moduli space in which the spectral curve
becomes the Seiberg--Witten curve and the ring reduces to the non-holomorphic
modular ring of the group . On that submanifold, the gap conditions
completely fix the holomorphic ambiguity and the model can be solved explicitly
to very high genus. We use these results to make precision tests of the
connection between the large order behavior of the 1/N expansion and
non-perturbative effects due to instantons. Finally, we argue that a full
understanding of the large genus asymptotics in the multi-cut case requires a
new class of non-perturbative sectors in the matrix model.Comment: 51 pages, 8 figure
Disease and Healing in Ancient Societies: Dental Calculus Residues and Skeletal Pathology Data Indicate Age- and Sex-Biased Medicinal Practices among Native Californians
The health of humans is intricately linked to the substances we ingest—both food and nondietary items. Adverse health outcomes related to smoking of such products as tobacco and other psychoactive substances are clearly established in modern populations but are less well understood for ancient communities. Grasping these dynamics is further complicated by the curative, religious, and medicinal context of many of these substances, which have often been commodified, refined, and altered in recent history. As part of a larger collaboration with the Muwekma Ohlone Tribe dedicated to understanding medicinal plant use among Native Californians, this article summarizes new metabolomic data from three Middle- and Late-Period ancestral heritage Ohlone sites: Thámien Rúmmeytak (CA-SCL-128), ’AyttakiÅ¡ ’Éete HiramwiÅ¡ Trépam-tak (CA-ALA-677/H), and SÃi Túupentak (CA-ALA-565/H). The authors used an ultra-performance liquid chromatography-mass spectrometry platform to analyze chemical residues from 95 human dental calculus samples from 50 burials. Using multivariate statistics, they coanalyzed demographic and skeletal pathology data with chemical residue profiles and considered skeletal markers for a series of oral and postcranial health conditions. Results indicate sex and age biases in consumption patterns. Periodontitis stands out as the most significant local factor for changes in the oral metabolome. However, while chemical markers of oral diseases may be related to pathogen activity, associations between residues and postcranial conditions such as osteoarthritis suggest traditional curative practices and the ingestion of medicinal substances. Hence, this study yields new insights into the broader context of illness and healing in the past
A Petal of the Sunflower: Photometry of the Stellar Tidal Stream in the Halo of Messier 63 (NGC 5055)
We present surface photometry of a very faint, giant arc feature in the halo
of the nearby spiral galaxy NGC 5055 (M63) that is consistent with being a part
of a stellar stream resulting from the disruption of a dwarf satellite galaxy.
This faint feature was first detected in early photographic studies by van der
Kruit (1979); more recently by Mart\'inez-Delgado et al. (2010) and as
presented in this work, the loop has been realized to be the result of a recent
minor merger through evidence obtained by deep images taken with a telescope of
only 0.16 m aperture. The stellar stream is confirmed in additional images
taken with the 0.5 m of the BlackBird Remote Observatory and the 0.8 m of the
McDonald Observatory. This low surface brightness structure around the disk of
the galaxy extends ~29 kpc from its center, with a projected width of 3.3 kpc.
The stream's morphology is consistent with that of the visible part of a
"great-circle" stellar stream originating from the accretion of a ~10^8 M_sun
dwarf satellite in the last few Gyr. The progenitor satellite's current
position and fate are not conclusive from our data. The color of the stream's
stars is consistent with Local Group dwarfs and is similar to the outer regions
of M63's disk and stellar halo. We detect other low surface brightness
"plumes"; some of these may be extended spiral features related to the galaxy's
complex spiral structure and others may be tidal debris associated with the
disruption of the galaxy's outer stellar disk as a result of the accretion
event. We differentiate between features related to the tidal stream and faint,
blue features in the outskirts of the galaxy's disk previously detected by the
GALEX satellite. With its highly warped HI gaseous disk (~20 deg), M63
represents one of several examples of an isolated spiral galaxy with a warped
disk showing strong evidence of an ongoing minor merger.Comment: 16 pages, 10 figures, 3 tables, Accepted for publication in The
Astronomical Journa
Assessment of ibrutinib plus rituximab in front-line CLL (FLAIR trial): study protocol for a phase III randomised controlled trial
Background Treatment of chronic lymphocytic leukaemia (CLL) has seen a substantial improvement over the last few years. Combination immunochemotherapy, such as fludarabine, cyclophosphamide and rituximab (FCR), is now standard first-line therapy. However, the majority of patients relapse and require further therapy, and so new, effective, targeted therapies that improve remission rates, reduce relapses, and have fewer side effects, are required. The FLAIR trial will assess whether ibrutinib plus rituximab (IR) is superior to FCR in terms of progression-free survival (PFS). Methods/design FLAIR is a phase III, multicentre, randomised, controlled, open, parallel-group trial in patients with previously untreated CLL. A total of 754 participants will be randomised on a 1:1 basis to receive standard therapy with FCR or IR. Participants randomised to FCR will receive a maximum of six 28-day treatment cycles. Participants randomised to IR will receive six 28-day cycles of rituximab, and ibrutinib taken daily for 6 years until minimal residual disease (MRD) negativity has been recorded for the same amount of time as it took to become MRD negative, or until disease progression. The primary endpoint is PFS according to the International Workshop on CLL (IWCLL) criteria. Secondary endpoints include: overall survival; proportion of participants with undetectable MRD; response to therapy by IWCLL criteria; safety and toxicity; health-related quality of life (QoL); and cost-effectiveness. Discussion The trial aims to provide evidence for the future first-line treatment of CLL patients by assessing whether IR is superior to FCR in terms of PFS, and whether toxicity rates are favourable. Trial registration ISRCTN01844152. Registered on 8 August 2014, EudraCT number 2013-001944-76. Registered on 26 April 2013
Intratumoral Delivery of Plasmid Interleukin-12 Via Electroporation Leads to Regression of Injected and Non-Injected Tumors in Merkel Cell Carcinoma
Purpose: Interleukin-12 (IL12) promotes adaptive type I immunity and has demonstrated antitumor efficacy, but systemic administration leads to severe adverse events (AE), including death. This pilot trial investigated safety, efficacy, and immunologic activity of intratumoral delivery of IL12 plasmid DNA (tavo) via in vivo electroporation (i.t.-tavo-EP) in patients with Merkel cell carcinoma (MCC), an aggressive virus-associated skin cancer.
Experimental Design: Fifteen patients with MCC with superficial injectable tumor(s) received i.t.-tavo-EP on days 1, 5, and 8 of each cycle. Patients with locoregional MCC (cohort A, N = 3) received one cycle before definitive surgery in week 4. Patients with metastatic MCC (cohort B, N = 12) received up to four cycles total, administered at least 6 weeks apart. Serial tumor and blood samples were collected.
Results: All patients successfully completed at least one cycle with transient, mild (grades 1 and 2) AEs and without significant systemic toxicity. Sustained (day 22) intratumoral expression of IL12 protein was observed along with local inflammation and increased tumor-specific CD8+ T-cell infiltration, which led to systemic immunologic and clinical responses. The overall response rate was 25% (3/12) in cohort B, with 2 patients experiencing durable clinical benefit (16 and 55+ months, respectively). Two cohort A patients (1 with pathologic complete remission) were recurrence-free at 44+ and 75+ months.
Conclusions: I.t.-tavo-EP was safe and feasible without systemic toxicity. Sustained local expression of IL12 protein and local inflammation led to systemic immune responses and clinically meaningful benefit in some patients. Gene electrotransfer, specifically i.t.-tavo-EP, warrants further investigation for immunotherapy of cancer
Structural properties of discs and bulges of early-type galaxies
We have used the EFAR sample of galaxies to study the light distributions of
early-type galaxies. We decompose the 2D light distribution of the galaxies in
a flattened spheroidal component with a Sersic radial light profile and an
inclined disc component with an exponential light profile. We show that the
brightest, bulge dominated elliptical galaxies have a fairly broad distribution
in the Sersic profile shape parameter n_B, with a median of about 3.7 and a
sigma of ~0.9. Other galaxies have smaller n_B values, meaning that spheroids
are in general less concentrated than the n_B=4 de Vaucouleurs-law profile.
The results of our light decompositions are robust, even though without
kinematic information we cannot prove that the spheroids and discs are really
pressure- and rotation-supported stellar systems. If we assume that the
detected spheroids and discs are indeed separate components, we can draw the
following conclusions: 1) the spheroid and disc scale sizes are correlated; 2)
bulge-to-total luminosity ratios, bulge effective radii, and bulge n_B values
are all positively correlated; 3) the bivariate space density distribution of
elliptical galaxies in the (luminosity, scale size)-plane is well described by
a Schechter luminosity function in and a log-normal scale-size distribution at
a given luminosity; 4) at the brightest luminosities, the scale size
distribution of elliptical galaxies is similar to those of bright spiral
galaxies; at fainter luminosities the elliptical scale size distribution peaks
at distinctly smaller sizes than the spiral galaxy distribution; and 5) bulge
components of early-type galaxies are typically a factor 1.5 to 2.5 smaller
than the disks of spiral galaxies, while disc components of early-type galaxies
are typically twice as large as the discs of spiral galaxies. [abridged]Comment: 16 pages, 18 figures. Accepted for publication in the MNRA
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