Parasitological examination of wasting disease in black abalone, Haliotis cracherodii : final report

Black abalone in southern California are afflicted with chronic intestinal infections of a rickettsia-like organism that causes a debilitating and fatal withering syndrome. The hematology of withered animals indicated that cellular degradation and apoptosis occurred in tandem with the · decline and catabolism of abalone tissues. Two types of hemocytes were found in the hemolymph. Type I and Type II Hyalinocytes were distinguished by subtle differences in their cytoplasmic vesicles. Densities of both types of hemocytes declined in abundance, and small, presumptive stem cells increased in abundance with the progression of the disease. No circulating granulocytes were present in hemolymph; but serous cells were present as fixed granulocytes in hemal spaces. Cellular inclusions, dying cells, and vacuolate cells increased in abundance with the disease. An evaluation of cellular immunity resulted in disparate findings associated with serum levels and types of buffer used. In the presence of micronutrients, and divalent metal ions, however, hemocytes from infected abalone showed increased degrees of phagocytosis (percent phagocytosis, and number of yeast particles per hemocyte) compared to hemocytes from uninfected animals. Experimental transmission of the disease was effected in healthy, unexposed abalone held together with asymptomatic, exposed abalone. Clinical signs of infection appeared after 180 days of cohabitation. The chronic nature of the disease progressed relatively unnoticed until 6 to 8 months when infected abalone began to show signs of withering. The withered condition represented an end stage of the disease and probably resulted from starvation caused by rickettsial disruption of the digestive processes

The Hyperparasite, Urosporidium spisuli sp. n. (Haplosporea), and Its Effects on the Surf Clam Industry

SSurf clams (Spisula solidissima) from along the Virginia and North Carolina coasts are infected with an immature anisakid nematode worm which does not cause economic concern until infected with the protozoan hyperparasite, Urosporidium spisuli sp. n. When the protozoan sporulates the spores give the worm a brownish-black appearance, thus making it readily visible in clam tissues. Light and electron microscope studies of the spores reveal characteristics which differentiate the protozoan from other species of Urosporidium. All spores are killed after 5 to 30 min at 100 C; therefore, the consumer would not ingest live spores when eating commercially prepared clam meat

Long-Term Multiwavelength Studies of High-Redshift Blazar 0836+710

Aims. The observation of gamma -ray flares from blazar 0836+710 in 2011, following a period of quiescence, offered an opportunity to study correlated activity at different wavelengths for a high-redshift (z=2.218) active galactic nucleus. Methods. Optical and radio monitoring, plus Fermi-LAT gamma-ray monitoring provided 2008-2012 coverage, while Swift offered auxiliary optical, ultraviolet, and X-ray information. Other contemporaneous observations were used to construct a broad-band spectral energy distribution. Results. There is evidence of correlation but not a measurable lag between the optical and gamma-ray flaring emission. On the contrary, there is no clear correlation between radio and gamma-ray activity, indicating radio emission regions that are unrelated to the parts of the jet that produce the gamma-rays. The gamma-ray energy spectrum is unusual in showing a change of shape from a power law to a curved spectrum when going from the quiescent state to the active state.Comment: 11 pages, 10 figures, Accepted for publication in A&

Detailed near-wake flowfield surveys with comparison to an Euler method of an aspect ratio 4 rectangular wing

An experimental investigation of the flowfield in the near-wake of an aspect ratio 4 rectangular wing was conducted, providing a complete detailed set of data for use in the validation of computational methods. An angle of attack of 8 degrees and two Reynolds numbers 530,000 and 391,000 were investigated using pitot and six-hole probes. In addition, two types of flow visualization were employed. The data presented includes contours of total pressure, mean velocity, flow angularity, and vorticity distribution data at five chordwise stations of the near-wake ranging from 0.167 to 5.00 chord lengths aft of the trailing edge. The experimental results were compared to the predicted results of a 2-D Euler numerical method. The results predicted by an Euler method failed to accurately define the flowfield. Tangential velocities remained relatively constant over the range of X/C considered though increased in angle of attack and Reynolds number did bring about corresponding increases. Axial velocities also increased with angle of attack and Reynolds number but showed greater sensitivity to increases in X/C. Graphic displays and contours of the total pressure data indicate that roll-up of the wing tip vortex is essentially complete one and one half chords downstream of the trailing edge

Supersymmetry, quark confinement and the harmonic oscillator

We study some quantum systems described by noncanonical commutation relations formally expressed as [q,p]=ihbar(I + chi H), where H is the associated (harmonic oscillator-like) Hamiltonian of the system, and chi is a Hermitian (constant) operator, i.e. [H,chi]=0 . In passing, we also consider a simple (chi=0 canonical) model, in the framework of a relativistic Klein-Gordon-like wave equation.Comment: To be published in Journal of Physics A: Mathematical and Theoretical (2007

Optical Absorption of CuO3_3 antiferromagnetic chains at finite temperatures

We use a high-statistic quantum Monte Carlo and Maximum Entropy regularization method to compute the dynamical energy correlation function (DECF) of the one-dimensional (1D) $S=1/2$ antiferromagnetic Heisenberg model at finite temperatures. We also present a finite temperature analytical ansatz for the DECF which is in very good agreement with the numerical data in all the considered temperature range. From these results, and from a finite temperature generalisation of the mechanism proposed by Lorenzana and Sawatsky [Phys. Rev. Lett. {\bf 74}, 1867 (1995)], we compute the line shape for the optical absorption spectra of multimagnon excitations assisted by phonons for quasi 1D compounds. The line shape has two contributions analogous to the Stokes and anti-Stokes process of Raman scattering. Our low temperature data is in good agreement with optical absorption experiments of CuO$_3$ chains in Sr$_2$CuO$_3$. Our finite temperature results provide a non trivial prediction on the dynamics of the Heisenberg model at finite temperatures that is easy to verify experimentally.Comment: 7 pages, 5 figure

Long-Term Multiwavelength Studies of High-Redshift Blazar 0836+710

Following gamma-ray flaring activity of high-redshift (z=2.218) blazar 0836+710 in 2011, we have assembled a long-term multiwavelength study of this object. Although this source is monitored regularly by radio telescopes and the Fermi Large Area Telescope, its coverage at other wavelengths is limited. The optical flux appears generally correlated with the gamma-ray flux, while little variability has been seen at X-ray energies. The gamma-ray/radio correlation is complex compared to some other blazars. As for many blazars, the largest variability is seen at gamma-ray wavelengths

Additional layers of gene regulatory complexity from recently discovered microRNA mechanisms

In recent years microRNAs have become recognized as pervasive, versatile agents of gene regulation. Some widely embraced rules involving Watson-Crick hybridization of microRNAs with mRNAs have generated great interest as scientists envision potential RNA cargoes for gene therapy and other experimental systems. However, while researchers ardently seek simplifying principles, nature seems very uncooperative. This article reviews some small RNA mechanisms that potentially regulate genes and which are not covered by previous microRNAs characterizations. In addition, we report here results of fluorescence microscopy experiments to directly demonstrate nuclear importation of small RNAs equal in length to typical mature microRNAs, implying that gene regulation at the locus of transcription might be possible

Higher Order Polarizabilities of the Proton

Compton scattering results are used to probe proton structure via measurement of higher order polarizabilities. Values for $\alpha_{E2}^p,\beta_{E2}^p,\alpha_{E\nu}^p,$ $\beta_{E\nu}^p$ determined via dispersion relations are compared to predictions based upon chiral symmetry and from the constituent quark model. Extensions to spin-polarizabilities are also discussed.Comment: 18 pages, revised version with one reference adde

MoonBEAM A Beyond Earth-Orbit GRB Detector for Multi-Messenger Astronomy

No abstract availabl