The impact of histopathology and NAB2-STAT6 fusion subtype in classification and grading of meningeal solitary fibrous tumor/hemangiopericytoma.

Meningeal solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) is a rare tumor with propensity for recurrence and metastasis. Although multiple classification schemes have been proposed, optimal risk stratification remains unclear, and the prognostic impact of fusion status is uncertain. We compared the 2016 WHO CNS tumor grading scheme (CNS-G), a three-tier system based on histopathologic phenotype and mitotic count, to the 2013 WHO soft-tissue counterpart (ST-G), a two-tier system based on mitotic count alone, in a cohort of 133 patients [59 female, 74 male; mean age 54 years (range 20-87)] with meningeal SFT/HPC. Tumors were pathologically confirmed through review of the first tumor resection (n = 97), local recurrence (n = 35), or distant metastasis (n = 1). A STAT6 immunostain showed nuclear expression in 132 cases. NAB2-STAT6 fusion was detected in 99 of 111 successfully tested tumors (89%) including the single STAT6 immunonegative tumor. Tumors were classified by CNS-G as grade 1 (n = 43), 2 (n = 41), or 3 (n = 49), and by ST-G as SFT (n = 84) or malignant SFT (n = 49). Necrosis was present in 16 cases (12%). On follow-up, 42 patients had at least one subsequent recurrence or metastasis (7 metastasis only, 33 recurrence only, 2 patients had both). Twenty-nine patients died. On univariate analysis, necrosis (p = 0.002), CNS-G (p = 0.01), and ST-G (p = 0.004) were associated with recurrence-free (RFS) but not overall survival (OS). NAB2-STAT6 fusion type was not significantly associated with RFS or OS, but was associated with phenotype. A modified ST-G incorporating necrosis showed higher correlation with RFS (p = 0.0006) and remained significant (p = 0.02) when considering only the primary tumors. From our data, mitotic rate and necrosis appear to stratify this family of tumors most accurately and could be incorporated in a future grading scheme

String Theory and Quantum Chromodynamics

I review recent progress on the connection between string theory and quantum chromodynamics in the context of the gauge/gravity duality. Emphasis is placed on conciseness and conceptual aspects rather than on technical details. Topics covered include the large-Nc limit of gauge theories, the gravitational description of gauge theory thermodynamics and hydrodynamics, and confinement/deconfinement thermal phase transitions.Comment: 38 pages, 24 figures. Lectures given at the RTN Winter School on "Strings, Supergravity and Gauge Theories" at CERN on January 15-19, 200

Investigation Of Ions Accelerated Through Electrostatic Menisci In An Inductively Coupled Plasma

Plasmas are used in semiconductor fabrication as they allow for very precise control over processes such as etching and doping. This is achieved by extracting a beam of ions from the plasma to interact with and modify the surface of a silicon wafer. However, conventional fabrication methods are reaching spatial limitations as semiconductor features reach the atomic scale. Therefore, in order to better control the fabrication processes and facilitate the transition to three-dimensional architecture, a greater understanding of ion beam formation is needed. Ion beams are extracted at the boundary between the Debye sheath and an externally applied potential, which forms a unipolar sheath. This boundary, known as the plasma meniscus, is dependent on source parameters and acts as an electrostatic lens for ions that traverse it. This allows for control of ion beam properties through the adjustment of the source parameters that affect the meniscus. Presented here is an investigation into the plasma meniscus and the dependence of its topology on controllable source parameters. The plasma meniscus is formed by graphite extraction optics with a 5 mm square aperture for beam extraction. 12 mm from the aperture is an electrically isolated graphite wafer that is biased to different potentials. Laser induced fluorescence is employed to obtain ion velocity distribution functions: inside the inductively coupled plasma source, at the extraction aperture, and in the downstream ion beam. The use of the confocal telescope allows for first, non-perturbative measurements of ions inside an inductively coupled plasma source. The ion source power is varied (Pf = 1 kW, 2 kW, 3 kW, 4 kW) at different applied wafer bias voltages (Vb = 0 V, 1000 V, 2000 V, 3000 V). Ion temperature, velocity, and relative density are calculated from the ion velocity distribution functions. The ions\u27 speed increases as they travel through the source and form the beam. Additionally, there is a second population of ions that appears near the plasma meniscus. These ions form a beam halo, which hinders the creation of a uniform ion beam. This effect is mitigated at a sufficiently high bias voltage

Microcystin Prevalence throughout Lentic Waterbodies in Coastal Southern California.

Toxin producing cyanobacterial blooms have increased globally in recent decades in both frequency and intensity. Despite the recognition of this growing risk, the extent and magnitude of cyanobacterial blooms and cyanotoxin prevalence is poorly characterized in the heavily populated region of southern California. Recent assessments of lentic waterbodies (depressional wetlands, lakes, reservoirs and coastal lagoons) determined the prevalence of microcystins and, in some cases, additional cyanotoxins. Microcystins were present in all waterbody types surveyed although toxin concentrations were generally low across most habitats, as only a small number of sites exceeded California's recreational health thresholds for acute toxicity. Results from passive samplers (Solid Phase Adsorption Toxin Tracking (SPATT)) indicated microcystins were prevalent throughout lentic waterbodies and that traditional discrete samples underestimated the presence of microcystins. Multiple cyanotoxins were detected simultaneously in some systems, indicating multiple stressors, the risk of which is uncertain since health thresholds are based on exposures to single toxins. Anatoxin-a was detected for the first time from lakes in southern California. The persistence of detectable microcystins across years and seasons indicates a low-level, chronic risk through both direct and indirect exposure. The influence of toxic cyanobacterial blooms is a more complex stressor than presently recognized and should be included in water quality monitoring programs

Protection of the Stratospheric Ozone Layer and the Structure of International Environmental Lawmaking

The Vienna Convention of 1985, the Montreal Protocol of 1987, and the London Amendments and Adjustments of 1990 constitute an international response to the problem of the depletion of the ozone layer by chloroflourocarbons. This Article describes the organization of parties under this international framework, and discusses the adoption of reduction schedules with delayed phaseout plans for developing countries. The Article points out that international lawmaking differs from international environmental lawmaking in that the latter involves greater uncertainty about reality, requires participation by major contributors to the depletion of the ozone layer, and poses the problem of being either unmanageably broad in scope or piecemeal in approach. These differences suggest that the solution to the depletion of the ozone layer is an ongoing process of lawmaking which emphasizes participation, manageable negotiations, and holistic thinking. Additionally, halting the depletion of the ozone layer requires scholarly discourse to make future negotiations successful and to create a scheme for the implementation of reduction schedules

Microcystin Prevalence throughout Lentic Waterbodies in Coastal Southern California.

Toxin producing cyanobacterial blooms have increased globally in recent decades in both frequency and intensity. Despite the recognition of this growing risk, the extent and magnitude of cyanobacterial blooms and cyanotoxin prevalence is poorly characterized in the heavily populated region of southern California. Recent assessments of lentic waterbodies (depressional wetlands, lakes, reservoirs and coastal lagoons) determined the prevalence of microcystins and, in some cases, additional cyanotoxins. Microcystins were present in all waterbody types surveyed although toxin concentrations were generally low across most habitats, as only a small number of sites exceeded California's recreational health thresholds for acute toxicity. Results from passive samplers (Solid Phase Adsorption Toxin Tracking (SPATT)) indicated microcystins were prevalent throughout lentic waterbodies and that traditional discrete samples underestimated the presence of microcystins. Multiple cyanotoxins were detected simultaneously in some systems, indicating multiple stressors, the risk of which is uncertain since health thresholds are based on exposures to single toxins. Anatoxin-a was detected for the first time from lakes in southern California. The persistence of detectable microcystins across years and seasons indicates a low-level, chronic risk through both direct and indirect exposure. The influence of toxic cyanobacterial blooms is a more complex stressor than presently recognized and should be included in water quality monitoring programs