14,199 research outputs found

    An Obstruction to Quantization of the Sphere

    Get PDF
    In the standard example of strict deformation quantization of the symplectic sphere S2S^2, the set of allowed values of the quantization parameter â„Ź\hbar is not connected; indeed, it is almost discrete. Li recently constructed a class of examples (including S2S^2) in which â„Ź\hbar can take any value in an interval, but these examples are badly behaved. Here, I identify a natural additional axiom for strict deformation quantization and prove that it implies that the parameter set for quantizing S2S^2 is never connected.Comment: 23 page. v2: changed sign conventio

    Unique Molecular Features in High-Risk Histology Endometrial Cancers

    Get PDF
    Endometrial cancer is the most common gynecologic malignancy in the United States and the sixth most common cancer in women worldwide. Fortunately, most women who develop endometrial cancer have low-grade early-stage endometrioid carcinomas, and simple hysterectomy is curative. Unfortunately, 15% of women with endometrial cancer will develop high-risk histologic tumors including uterine carcinosarcoma or high-grade endometrioid, clear cell, or serous carcinomas. These high-risk histologic tumors account for more than 50% of deaths from this disease. In this review, we will highlight the biologic differences between low- and high-risk carcinomas with a focus on the cell of origin, early precursor lesions including atrophic and proliferative endometrium, and the potential role of stem cells. We will discuss treatment, including standard of care therapy, hormonal therapy, and precision medicine-based or targeted molecular therapies. We will also discuss the impact and need for model systems. The molecular underpinnings behind this high death to incidence ratio are important to understand and improve outcomes

    Preliminary Canopy Removal Experiments in Algal Dominated Communities Low on the Shore and in the Shallow Subtidal on the Isle of Man

    No full text
    The algal dominated communities immediately above and below the low-water spring level on a moderately exposed Manx shore were investigated by canopy removal experiments. Fucus serratus, Laminaria digitata and L. hyperborea were removed. Competition was shown to be important in determining the zonation of L. digitata and the distribution along the wave exposure gradient of other species such as Alaria esculenta, Desmarestia aculeata and D. viridis, and L. saccharina. Many species of algal epiphytes were early colonizers of canopy removal areas suggesting that competition from canopy algae usually restricts them to an epiphytic habit. The results indicate that interactions between macrophytes are much more important than grazing in structuring these communities

    Time, institutional support and quality of decision making in child protection:A cross-country analysis

    Get PDF
    This paper examines perceptions of time and institutional support for decision making and staff confidence in child welfare staffs ultimate decisions – examining differences and similarities between and within the service-oriented Nordic countries (Norway and Finland) and the risk-oriented Anglo-American countries (England and California). The study identifies a high degree of work pressure across all the countries, lines of predominantly vertical institutional support and relatively high confidence in decisions. Finland stands out with higher perceived work pressure and with a horizontal support line, whereas England stands out with workers having a lower degree of confidence in their own and others’ decisions

    Rickettsial and Mollicute Infections in Hepatopancreatic Cells of Cultured Pacific White Shrimp (\u3ci\u3ePenaeus vannamei\u3c/i\u3e)

    Get PDF
    Infections by multiple species of bacteria occurred in hepatopancreatic epithelial cells of cultured Pacific white shrimp (Penaeus vannamei). Grossly, hepatopancreases of moribund shrimp were pale white. Light microscopically, hepatopancreatic tubules appeared atrophied and were associated with granulomas. Examination by scanning and transmission electron microscopy revealed heavy cytoplasmic infections by three forms of microorganisms: (1) a rickettsia-like bacterium, (2) a helical form of a mollicute-like bacterium, and (3) a filamentous mollicute-like bacterium. The rod-shaped rickettsia (900 nm long by 300 nm wide) appeared to be free in the cytoplasm and had both a plasma membrane and a cell wall. Neither form of mollicute possessed a cell wall. The helical mollicute was blunt at its wide end (about 260 nm in diameter) where it contained electron-lucent bodies. Helical turns along its tapered axis resembled those of a spiroplasma (the only helical form of mycoplasma in the class Mollicutes) or a spirochete. The helical bacterium did not possess periplasmic flagella characteristic of spirochetes, which lends support to its being a type of spiroplasma. The filamentous mollicute consisted of masses of short, branched filaments 60 nm wide with intermittent spherical dilations and terminal blebs on the branches. The presumed mollicutes have not been reported previously in crustaceans. Each bacterium, or concurrent infections of the bacteria, are pathogenic to cultured shrimp, could impact culture operations, and thus deserve more study
    • …
    corecore