The Phoenicians in Arcadia Essai de Méthode en Mythologie Grecque: De l' Origine des Cultes Arcadiens: Victor Béraed. Paris: Thorin. 1894. 12fr.5O.

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Acoel and platyhelminth models for stem-cell research

Acoel and platyhelminth worms are particularly attractive invertebrate models for stem-cell research because their bodies are continually renewed from large pools of somatic stem cells. Several recent studies, including one in BMC Developmental Biology, are beginning to reveal the cellular dynamics and molecular basis of stem-cell function in these animals

Dividend Tax Capitalization and Liquidity

We provide a new explanation for cross-sectional variation in dividend tax capitalization. Our analysis is twofold. First, we conduct a theoretical analysis that shows that liquidity (illiquidity) mitigates (magnifies) the positive effect of dividend taxes on expected rates of return documented in prior literature. Second, we conduct an empirical analysis centered around the Jobs and Growth Tax Relief and Reconciliation Act of 2003, which reduced the difference between the maximum statutory dividend and capital gains tax rates, and find results consistent with our theory. We also provide results suggesting that institutional ownership’s mitigating effect on dividend tax capitalization documented in prior studies is attributable to stocks with greater institutional ownership being more liquid and not to the “marginal investor” being insensitive to dividend taxes

Acoel and Platyhelminth Models for Stem-cell Research

Acoel and platyhelminth worms are particularly attractive invertebrate models for stem-cell research because their bodies are continually renewed from large pools of somatic stem cells. Several recent studies, including one in BMC Developmental Biology, are beginning to reveal the cellular dynamics and molecular basis of stem-cell function in these animals. See research article http://www.biomedcentral.com/1471-213X/9/69. Adult somatic stem cells can play critical roles in postembryonic developmental processes such as tissue renewal, growth, repair, and regeneration [1]. Understanding how such cells are maintained and produce differentiated progeny is thus of general interest in developmental biology, in addition to being of clear biomedical relevance. Invertebrate models have great potential for elucidating the cellular and molecular basis of stem-cell function. However, in the main invertebrate models used for dissecting the details of animal development, including Drosophila and Caenorhabditis, adult somatic tissues are primarily post-mitotic and are largely or entirely devoid of adult stem cells, which limits the use of these established models for stem-cell research. Representatives of two groups of soft-bodied worms, the Acoela and the Platyhelminthes, possess large pools of adult somatic stem cells, making them useful invertebrate models for stem-cell biology. These organisms are now beginning to provide new insights into the cellular and molecular basis of adult stem-cell function

Staged inertial microfluidic focusing for complex fluid enrichment

Microfluidic inertial focusing reliably and passively aligns small particles and cells through a combination of competing inertial fluid forces. The equilibrium behavior of inertially focused particles in straight channels has been extensively characterized and has been shown to be a strong function of channel size, geometry and particle size. We demonstrate that channels of varying geometry may be combined to produce a staged device capable of high throughput particle and cell concentration and efficient single pass complex fluid enrichment. Straight and asymmetrically curved microchannels were combined in series to accelerate focusing dynamics and improve concentration efficiency. We have investigated single and multiple pass concentration efficiency and results indicate that these devices are appropriate for routine cell handling operations, including buffer exchange. We demonstrate the utility of these devices by performing a ubiquitous fluorescence staining assay on-chip while sacrificing very little sample or processing time relative to centrifugation. Staged concentration is particularly desirable for point of care settings in which more conventional instrumentation is impractical or cost-prohibitive.United States. Department of Defense (Congressionally Directed Medical Research Program, Prostate Cancer Research Program Award number W81XWH-13-1-0272)University of Wyoming. IDeA Networks of Biomedical Research Excellence (program P20RR016474)University of Wyoming. IDeA Networks of Biomedical Research Excellence (program P20GM103432)United States. Department of Defense (Congressionally Directed Medical Research Program, Prostate Cancer Research Program Award number W81XWH-13-1-0273)United States. National Aeronautics and Space Administration (Wyoming NASA Space Grant Consortium (NASA Grant #NNX10A095H))National Science Foundation (U.S.) (Wyoming Experimental Program to Stimulate Competitive Research (Grant EPS-0447681)

Community structure of soil fungi in a novel perennial crop monoculture, annual agriculture, and native prairie reconstruction

The use of perennial crop species in agricultural systems may increase ecosystem services and sustainability. Because soil microbial communities play a major role in many processes on which ecosystem services and sustainability depend, characterization of soil community structure in novel perennial crop systems is necessary to understand potential shifts in function and crop responses. Here, we characterized soil fungal community composition at two depths (0–10 and 10–30 cm) in replicated, long-term plots containing one of three different cropping systems: a tilled three-crop rotation of annual crops, a novel perennial crop monoculture (Intermediate wheatgrass, which produces the grain Kernza®), and a native prairie reconstruction. The overall fungal community was similar under the perennial monoculture and native vegetation, but both were distinct from those in annual agriculture. The mutualist and saprotrophic community subsets mirrored differences of the overall community, but pathogens were similar among cropping systems. Depth structured overall communities as well as each functional group subset. These results reinforce studies showing strong effects of tillage and sampling depth on soil community structure and suggest plant species diversity may play a weaker role. Similarities in the overall and functional fungal communities between the perennial monoculture and native vegetation suggest Kernza® cropping systems have the potential to mimic reconstructed natural systems

ヒト前立腺癌の進行モデルと新しい治療法

著者等はヒト前立腺癌の進展に関した2つの細胞モデルを開発した.LNCaP前立腺癌進展モデルは, 生体内での前立腺又は骨の間質細胞とLNCaP細胞との相互作用に基づいており, これによって腫瘍形成能と転移能を獲得したものである.派生株C4-2は去勢動物で容易に発育し, リンパ節, 精嚢腺, 骨に転移する.次のモデルARCaPは, 癌性腹水由来のヒト前立腺癌細胞で, アンドロゲン及びエストロゲンによって増殖を抑制され, 去勢下で腫瘍を形成した.ARCaPはアンドロゲン受容体及びPSAを低レベルで発現し, 同所移植によって肝, 腎, 骨等に高頻度で転移した.これらのモデルを用いて遺伝子治療の研究を行ったOur laboratory has developed two cellular models of human prostate cancer progression. The LNCaP prostate cancer progression model is based upon the well-known cellular interaction between human prostate or bone stromal cells and LNCaP cells in vivo. The marginally tumorigenic LNCaP cells acquired tumorigenic and metastatic potential upon cellular interaction with either prostate or bone fibroblasts. A subline termed C4-2 was observed to grow readily in castrated animals and acquired metastatic potential spreading from the primary tumor site to the lymph node, the seminal vesicles, and the axial skeleton, resulting in an intense osteoblastic reaction. The second model is ARCaP, where prostate cancer cells derived from the ascites fluid of a man with metastatic disease exhibited an Androgen- and estrogen-Repressed Prostate Cancer cell growth and tumor formation in either a hormone-deficient or a castrated environment. However, the growth of either the tumor cells in vitro or the tumors in vivo was suppressed by both estrogen and androgen. While the tumor cells expressed low levels of androgen receptor and prostate-specific antigen (PSA), they were highly metastatic when inoculated orthotopically. Distant metastases to a number of organs were detected, including the liver, lung, kidney, and bone. We have employed a human prostate cancer progression model as a system to study the efficacy of gene therapy. Results of the study show that whereas universal promoters, such as Cytomegalovirus (CMV) and Rous Sarcoma Virus (RSV) promoter-driven tumor suppressors (e.g. p53, p21, and p16), were effective in inhibiting prostate tumor growth, the advantages of driving the expression of therapeutic toxic genes using a tissue-specific promoter prostate-specific antigen (PSA) and a tumor--but not tissue-specific promoter, osteocalcin (OC), are preferred. In the case of the PSA promoter, we can achieve cell-kill in PSA-producing human prostate cancer cells. To circumvent the supporting role of bone stroma for prostate cancer epithelial growth, we have recently developed a novel concept where the expression of therapeutic toxic genes is driven by a tumor--but not a tissue-specific OC promoter. Osteocalcin-thymidine kinase (OC-TK) was found to efficiently eradicate the growth of osteosarcoma, prostate, and brain tumors both in vitro and in vivo. We observed that androgen-independent human prostate cancer cells lines expressed OC-TK at higher levels than androgen-dependent human prostate cancer cell lines. We have obtained data to suggest that Ad-OC-TK plus a pro-drug acyclovir (ACV) may be used as an effective therapy to treat prostate cancer bone metastasis in models where the growth of androgen-independent PC-3 and C4-2 tumors in the bone has occurred

Negative refraction using Raman transitions and chirality

We present a scheme that achieves negative refraction with low absorption in far-off resonant atomic systems. The scheme utilizes Raman resonances and does not require the simultaneous presence of an electric-dipole transition and a magnetic-dipole transition near the same wavelength. We show that two interfering Raman transitions coupled to a magnetic-dipole transition can achieve a negative index of refraction with low absorption through magnetoelectric cross-coupling. We confirm the validity of the analytical results with exact numerical simulations of the density matrix. We also discuss possible experimental implementations of the scheme in rare-earth metal atomic systems. The concept of negative refraction, which was first predicted by Veselago [1] more than four decades ago, has recently emerged as a very exciting field of science. In his seminal paper, Veselago argued that materials with simultaneously negative permittivity and permeability would acquire a negative index of refraction, n < 0 [1]. These materials exhibit many seemingly strange properties such as the electromagnetic vectors forming a left-handed triad (hence the term left-handed materials) and the Poynting vector being antiparallel to the k vector. Although the interest in these materials remained only a scientific curiosity for a long time, it is now understood that negative refraction may have important and far-reaching practical consequences. The key potential application for these materials was discovered in the year 2000 when Pendry predicted that a slab with a negative index of refraction, known as a perfect lens, can image objects with, in principle, unlimited resolution Materials with a negative index of refraction do not exist naturally, and thus they need to be artificially constructed. One approach is to artificially engineer periodic metal-dielectric structures with appropriate electric and magnetic resonances. These structures, termed metamaterials, typically have a characteristic periodicity scale smaller than the wavelength so that a nearly uniform electromagnetic response is obtained. Initial experiments have demonstrated negative refraction in the microwave region of the spectrum using metamaterials constructed from metal wires and split-ring resonators In this paper, we focus on atomic systems that are driven with lasers in their internal states so that negative refraction for a weak probe wave is achieved. The key advantages of using driven atomic systems as opposed to metamaterials are (i) using interference principles, one can obtain a negative index of refraction with negligible absorption; (ii) atomic systems are uniquely suited for achieving negative refraction at shorter and shorter wavelengths, particularly in the visible and ultraviolet regions of the spectrum; (iii) since negative refraction is achieved through manipulation of internal states, the properties of the material can be dynamically modified, opening an array of exciting applications including perfectlens switches. Despite these advantages, achieving negative refraction in atomic systems is a very challenging problem that has not yet been experimentally demonstrated due to several difficulties. All recent proposals require a strong electricdipole transition and a strong magnetic-dipole transition at almost exactly the same wavelength. It is difficult to satisfy this condition in real atomic systems. Furthermore, achieving negative permittivity and permeability simultaneously requires atomic densities greater than 10 18 cm −3 , which is impractical. We have recently suggested an approach that overcomes some of these difficulties 053836-

Abiotic and biotic context dependency of perennial crop yield

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Perennial crops in agricultural systems can increase sustainability and the magnitude of ecosystem services, but yield may depend upon biotic context, including soil mutualists, pathogens and cropping diversity. These biotic factors themselves may interact with abiotic factors such as drought. We tested whether perennial crop yield depended on soil microbes, water availability and crop diversity by testing monocultures and mixtures of three perennial crop species: a novel perennial grain (intermediate wheatgrass—Thinopyrum intermedium-- that produces the perennial grain Kernza®), a potential perennial oilseed crop (Silphium intregrifolium), and alfalfa (Medicago sativa). Perennial crop performance depended upon both water regime and the presence of living soil, most likely the arbuscular mycorrhizal (AM) fungi in the whole soil inoculum from a long term perennial monoculture and from an undisturbed native remnant prairie. Specifically, both Silphium and alfalfa strongly benefited from AM fungi. The presence of native prairie AM fungi had a greater benefit to Silphium in dry pots and alfalfa in wet pots than AM fungi present in the perennial monoculture soil. Kernza did not benefit from AM fungi. Crop mixtures that included Kernza overyielded, but overyielding depended upon inoculation. Specifically, mixtures with Kernza overyielded most strongly in sterile soil as Kernza compensated for poor growth of Silphium and alfalfa. This study identifies the importance of soil biota and the context dependence of benefits of native microbes and the overyielding of mixtures in perennial crops.Perennial Agricultural Project sponsored by the Malone Family Land Preservation FoundationNational Science Foundation (DEB-1556664, DEB- 1738041, OIA 1656006