175 research outputs found
Stable iPEPO Tensor-Network Algorithm for Dynamics of Two-Dimensional Open Quantum Lattice Models
Being able to accurately describe the dynamics steady states of driven and/or dissipative but quantum correlated lattice models is of fundamental importance in many areas of science: from quantum information to biology. An efficient numerical simulation of large open systems in two spatial dimensions is a challenge. In this work, we develop a tensor network method, based on an infinite projected entangled pair operator ansatz, applicable directly in the thermodynamic limit. We incorporate techniques of finding optimal truncations of enlarged network bonds by optimizing an objective function appropriate for open systems. Comparisons with numerically exact calculations, both for the dynamics and the steady state, demonstrate the power of the method. In particular, we consider dissipative transverse quantum Ising, driven-dissipative hard-core boson, and dissipative anisotropic
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models in non-mean-field limits, proving able to capture substantial entanglement in the presence of dissipation. Our method enables us to study regimes that are accessible to current experiments but lie well beyond the applicability of existing techniques
Essential requirements for setting up a stem cell processing laboratory
The Graft Processing subcommittee of the Worldwide Network for Blood and Marrow Transplantation wrote this guideline to assist physicians and laboratory technologists with the setting up of a cell processing laboratory (CPL) to support a hematopoietic stem cell transplant program, thereby facilitating the start-up of a transplant program in a new location and improving patient access to transplantation worldwide. This guideline describes the minimal essential features of designing such a laboratory and provides a list of equipment and supply needs and staffing recommendations. It describes the typical scope of services that a CPL is expected to perform, including product testing services, and discusses the basic principles behind the most frequent procedures. Quality management (QM) principles specific to a CPL are also discussed. References to additional guidance documents that are available worldwide to assist with QM and regulatory compliance are also provided. © 2014 Macmillan Publishers Limited All rights reserved
Environmental variables, habitat discontinuity and life history shaping the genetic structure of Pomatoschistus marmoratus
Coastal lagoons are semi-isolated ecosystems
exposed to wide fluctuations of environmental conditions
and showing habitat fragmentation. These features may
play an important role in separating species into different
populations, even at small spatial scales. In this study, we
evaluate the concordance between mitochondrial (previous
published data) and nuclear data analyzing the genetic
variability of Pomatoschistus marmoratus in five localities,
inside and outside the Mar Menor coastal lagoon (SE
Spain) using eight microsatellites. High genetic diversity
and similar levels of allele richness were observed across
all loci and localities, although significant genic and
genotypic differentiation was found between populations
inside and outside the lagoon. In contrast to the FST values
obtained from previous mitochondrial DNA analyses
(control region), the microsatellite data exhibited significant
differentiation among samples inside the Mar Menor
and between lagoonal and marine samples. This pattern
was corroborated using Cavalli-Sforza genetic distances.
The habitat fragmentation inside the coastal lagoon and
among lagoon and marine localities could be acting as a
barrier to gene flow and contributing to the observed
genetic structure. Our results from generalized additive
models point a significant link between extreme lagoonal
environmental conditions (mainly maximum salinity) and
P. marmoratus genetic composition. Thereby, these environmental
features could be also acting on genetic structure
of coastal lagoon populations of P. marmoratus favoring
their genetic divergence. The mating strategy of P. marmoratus
could be also influencing our results obtained from
mitochondrial and nuclear DNA. Therefore, a special
consideration must be done in the selection of the DNA
markers depending on the reproductive strategy of the
species
Regulatory T cells and their role in rheumatic diseases: a potential target for novel therapeutic development
Regulatory T cells have an important role in limiting immune reactions and are essential regulators of self-tolerance. Among them, CD4+CD25high regulatory T cells are the best-described subset. In this article, we summarize current knowledge on the phenotype, function, and development of CD4+CD25high regulatory T cells. We also review the literature on the role of these T cells in rheumatic diseases and discuss the potential for their use in immunotherapy
A Multicenter Randomized Clinical Trial Evaluating Interleukin-2 Activated Hematopoietic Stem Cell Transplantation and Post-transplant IL-2 for High Risk Breast Cancer Patients
This Phase III randomized multicenter trial compared progression-free (PFS) and overall survival (OS) for autologous peripheral blood stem cell (aPBSC) transplantation with or without immunotherapy in high-risk breast cancer patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44232/1/10549_2005_Article_4445.pd
Life history and population genetic structure of sea stars from the family Asterinidae
Life history can influence population genetic variation by altering patterns of gamete union and dispersal. Sea stars from the family Asterinidae have evolved similar life histories multiple times in parallel including planktonic feeding larvae, planktonic non-feeding larvae, development in benthic egg masses, and viviparity. In this thesis I first examine the population genetic structure of a widespread planktotrophic asterinid sea star from the East Pacific (Patiria miniata). I use mitochondrial sequence markers to determine whether extrinsic factors such as vicariance or intrinsic properties such as dispersal mode are driving patterns of population genetic variation in this species. I then examine patterns of population genetic variation among eight additional asterinid species from Australia using a mixed species pool of genomic microsatellite markers. I use these microsatellite markers to characterize the genetic variation within groups of brooded offspring associated with the unusual life histories of two live bearing asterinids from the genus Parvulastra. Lastly, I examine the evolution of life history among the asterinids and use the phylogenetic relationships among species to examine the correlation between life history and population genetic structure in this group. Ultimately, I find that the degree to which intrinsic life history properties of asterinids and extrinsic factors contribute to population genetic variation varies among species and among clades. In P. miniata patterns of population genetic variation are influenced by both intrinsic and extrinsic factors. Using microsatellite markers I find that in general between-population genetic variation is high in benthic species (benthic egg laying and live bearing) relative to species with planktonic larvae and that genetic variation within populations is lower in benthic species relative to planktonic species. Lastly, I find that the degree to which phylogeny constrains the coevolution of population genetic structure and life history varies among life history characters and among-population genetic parameters. This thesis suggests that in many cases variation in life histories among a closely related group of marine species can predict patterns of population genetic variation. However, extrinsic factors can in some cases, act with or override life history characteristics in driving patterns of population genetic variation
Morphological and genetic variation indicate cryptic species within Lamarck’s little sea star, Parvulastra (=Patiriella) exigua
The asterinid sea star Parvulastra exigua (Lamarck) is a common member of temperate intertidal marine communities from geographically widespread sites around the southern hemisphere. Individuals from Australian populations lay benthic egg masses (through orally directed gonopores) from which nonplanktonic offspring hatch and metamorphose without a dispersing planktonic larval phase. Scattered reports in the taxonomic literature refer to a similar form in southern Africa with aborally directed gonopores (and possibly broadcast spawning of planktonic eggs and larvae); such differences would be consistent with cryptic species variation. Surveys of morphology and mtDNA sequences have revealed cryptic species diversity in other asterinid genera. Here we summarize the taxonomic history of Lamarck’s "Astérie exiguë" and survey morphological variation (the location of the gonopores) for evidence that some P. exigua populations include cryptic species with a different mode of reproduction. We found strong evidence for multiple species in the form of two phenotypes and modes of reproduction (oral and aboral gonopore locations) in populations from southern Africa and islands in the Atlantic and Indian oceans. Both modes of reproduction have broad geographic ranges. These results are consistent with previously published genetic data that indicate multiple species in African and island (but not Australian) populations
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