Pacific bonito management information document

Management of Pacific bonito in California is examined in this Management Information Document by a State-Federal team of scientists. Abundance of Pacific bonito in southern California has fallen dramatically between the 1963-1969 period and the 1974-1977 period. Since 1976 the commercia1 fleet has found few large fish in southern California, and has caught fish in the size range of 15 to 57 cm (1.2 to 4.7 pounds). This fact, coupled with the low abundance indices, point out the need for a more active management regime. To develop management measures for the California bonito fishery both a surplus yield analysis and a yield-per-recruit analysis were performed. A maximum sustained yield of 10,000 short tons was estimated for the fishery in southern California, while the whole fishery, including Baja California, has an estimated MSY of 13,000 tons. In order to achieve this level of catch, however, the stock abundance must be increased by a factor of five. Yield-per-recruit considerations suggest that a minimum size limit in the commercial fishery has two important effects. A three-pound size limit could result in a slight increase in yield-per-recruit. If the size limit is increased to 5 or 7.5 lbs, the yield-per-recruit would fall significantly. Offsetting the effect on yield-per-recruit, however, would be a substantial increase in average amount of spawning per recruit which should result in a proportional increase in recruitment. With the current depressed stock abundance both a reduced annual take and a minimum size limit on commercial catch would confer substantial benefits in the form of an increase in the future stock size. After considering seven different types of management measures, the team finds that three types -- an annual commercial catch quota, a commercial size limit, and a recreational bag limit -- appear desirable. Re-establishment of the stock in southern California was the major consideration in this evaluation because the stock is currently depressed. All segments of the fishery will benefit from a more abundant resource. The difficult issues for policy, however, concern the rate of rebuilding, the degree of risk that is acceptable, and the distribution of benefits among user groups. By judicious choice among the options discussed here, a variety of positions can be established with respect to these issues. The greater the size limit, for instance, the more benefit is provided the recreational sector while difficulties are imposed upon commercial fishermen. The higher the quotas adopted, the slower the stock rebuilding and the greater the risk of continued stock depletion. A final reconciliation of the management options involves social, political and legal considerations which must be thoroughly incorporated by decision-makers before adoption of a management plan. (93pp.

Far-infrared mapping of the starburst galaxy NGC 253 with ISOPHOT

A 180 micron map and strip maps at 120 and 180 microns were obtained for the edge-on starburst galaxy NGC 253 with ISOPHOT, the photometer on board the Infrared Space Observatory. We compare these observations with those obtained by IRAS at 60 micron and 100 micron and derive the far--infrared spectral energy distribution at different locations in the galaxy. There is evidence for the presence of cold dust (T < 20 K) both in the nucleus and in the disk. Extended emission dominated by cold dust is detected up to 15 arcmin (~ 10 kpc) along the major and minor axis; its spatial distribution is similar to that seen in the IRAS and ROSAT PSPC images. The emission along the minor axis is probably related to large-scale outflows of gas (superwinds) which originate in the nuclear starburst and maybe to star formation in the halo. The radial dependence of the dust temperature along the major axis is found using a radiative transfer code: we show that the dust scale length in the disk is ~ 40% larger than that of stars.Comment: 10 pages, 12 figures. Accepted for publication in Astronomy & Astrophysic

Overview of Organic Food Crop Systems in Hawaii

This publication presents results of a needs assessment (also called an industry analysis) conducted in mid-2007 for the organic food crop producers in Hawaii. Seventy-six people participated, completing a survey (instrument included in the document) and providing comments during assessment meetings. Bottlenecks (constraints) were identified and prioritized by the participants, and actions to alleviate them were proposed

Polarized Broad-Line Emission from Low-Luminosity Active Galactic Nuclei

In order to determine whether unified models of active galactic nuclei apply to low-luminosity objects, we have undertaken a spectropolarimetric survey of of LINERs and Seyfert nuclei at the Keck Observatory. The 14 objects observed have a median H-alpha luminosity of 8x10^{39} erg/s, well below the typical value of ~10^{41} erg/s for Markarian Seyfert nuclei. Polarized broad H-alpha emission is detected in three LINERs: NGC 315, NGC 1052, and NGC 4261. Each of these is an elliptical galaxy with a double-sided radio jet, and the emission-line polarization in each case is oriented roughly perpendicular to the jet axis, as expected for the obscuring torus model. NGC 4261 and NGC 315 are known to contain dusty circumnuclear disks, which may be the outer extensions of the obscuring tori. The detection of polarized broad-line emission suggests that these objects are nearby, low-luminosity analogs of obscured quasars residing in narrow-line radio galaxies. The nuclear continuum of the low-luminosity Seyfert 1 galaxy NGC 4395 is polarized at p = 0.67%, possibly the result of an electron scattering region near the nucleus. Continuum polarization is detected in other objects, with a median level of p = 0.36% over 5100-6100 A, but in most cases this is likely to be the result of transmission through foreground dust. The lack of significant broad-line polarization in most type 1 LINERs is consistent with the hypothesis that we view the broad-line regions of these objects directly, rather than in scattered light.Comment: 28 pages, including 3 tables and 16 figures. Uses the emulateapj latex style file. Accepted for publication in The Astrophysical Journa

Exceptional Response with Immunotherapy in a Patient with Anaplastic Thyroid Cancer

Chemotherapy with or without radiation is the standard therapy for anaplastic thyroid cancer (ATC), although the response rate is not high and not durable. We describe a 62-year-old male who was diagnosed with ATC and initially treated with a thyroidectomy and lymph node dissection, followed by chemotherapy. Next generation sequencing was then performed to guide therapy and the tumor was found to have BRAF and programmed death-ligand 1 (PD-L1) positivity that was subsequently treated with vemurafenib and nivolumab. This led to substantial regression of tumor nodules. Genomic sequencing-based approaches to identify therapeutic targets has potential for improving outcomes. Currently, the patient continues to be in complete radiographic and clinical remission 20 months after beginning treatment with nivolumab. KEY POINTS: Programmed death-1 (PD-1)/PD-L1 immunotherapy has shown evidence of durable responses in certain malignancies such as melanoma, lung cancer, and renal cell carcinoma.PD-L1 positive tumors promote autoimmunity against the tumor; therefore, PD-1/PD-L1 blockade may be beneficial.Molecular profiling could possibly result in improved targeted therapy for certain malignancies

Formation of Large-Scale Obscuring Wall and AGN Evolution Regulated by Circumnuclear Starbursts

By considering the radiative force by a circumnuclear starburst as well as an AGN, we analyze the equilibrium configuration and the stability of dusty gas in the circumnuclear regions. It is found that the radiative force by an intensive starburst can support a stable gaseous wall with a scale-height of several hundred parsecs. Moreover, by taking the simple stellar evolution in the starburst into account, we find that the covering factor of the wall decreases on a time-scale of several $10^7$ yr. The large-scale wall, if formed, works to obscure the nucleus due to the dust opacity. Hence, it is anticipated that the index of AGN type tends to shift from higher to lower in several $10^7$ yr according as the circumnuclear starburst becomes dimmer. On the other hand, if the AGN itself is brighter than the circumnuclear starburst (e.g. quasar case), no stable large-scale wall forms. In that case, the AGN is highly probably identified as type 1. The present mechanism may provide a physical explanation for the putative correlation between AGN type and host properties that Sy2's are more frequently associated with circumnuclear starbursts than Sy1's, whereas quasars are mostly observed as type 1 regardless of star-forming activity in the host galaxies.Comment: 10 pages, 3 figures, ApJ Letters in pres

Dephasing model for spatially extended atomic states in cyclotronlike resonances

In recent work, the formation of ring-shaped electron distributions for hydrogen atoms in resonant static magnetic-laser fields has exclusively been associated with the impact of relativity. In this note we will generalize this statement and show that the nonlinearity associated with the nuclear binding force can trigger similarly shaped steady-state charge clouds in atoms under suitable conditions. The dephasing model, based on modeling the quantum-mechanical state by a classical ensemble of quasiparticles evolving with slightly different cyclotron periods, can recover features, in the two lowest-order resonances as well as the Coulomb-field-induced charge distributions

Galaxy-galaxy weak-lensing measurement from SDSS: II. host halo properties of galaxy groups

As the second paper of a series on studying galaxy-galaxy lensing signals using the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), we present our measurement and modelling of the lensing signals around groups of galaxies. We divide the groups into four halo mass bins, and measure the signals around four different halo-center tracers: brightest central galaxy (BCG), luminosity-weighted center, number-weighted center and X-ray peak position. For X-ray and SDSS DR7 cross identified groups, we further split the groups into low and high X-ray emission subsamples, both of which are assigned with two halo-center tracers, BCGs and X-ray peak positions. The galaxy-galaxy lensing signals show that BCGs, among the four candidates, are the best halo-center tracers. We model the lensing signals using a combination of four contributions: off-centered NFW host halo profile, sub-halo contribution, stellar contribution, and projected 2-halo term. We sample the posterior of 5 parameters i.e., halo mass, concentration, off-centering distance, sub halo mass, and fraction of subhalos via a MCMC package using the galaxy-galaxy lensing signals. After taking into account the sampling effects (e.g. Eddington bias), we found the best fit halo masses obtained from lensing signals are quite consistent with those obtained in the group catalog based on an abundance matching method, except in the lowest mass bin. Subject headings: (cosmology:) gravitational lensing, galaxies: clusters: generalComment: 12 pages, 7 figures, submitted to Ap

Searching for galaxy clusters in the Kilo-Degree Survey

In this paper, we present the tools used to search for galaxy clusters in the Kilo Degree Survey (KiDS), and our first results. The cluster detection is based on an implementation of the optimal filtering technique that enables us to identify clusters as over-densities in the distribution of galaxies using their positions on the sky, magnitudes, and photometric redshifts. The contamination and completeness of the cluster catalog are derived using mock catalogs based on the data themselves. The optimal signal to noise threshold for the cluster detection is obtained by randomizing the galaxy positions and selecting the value that produces a contamination of less than 20%. Starting from a subset of clusters detected with high significance at low redshifts, we shift them to higher redshifts to estimate the completeness as a function of redshift: the average completeness is ~ 85%. An estimate of the mass of the clusters is derived using the richness as a proxy. We obtained 1858 candidate clusters with redshift 0 < z_c < 0.7 and mass 13.5 < log(M500/Msun) < 15 in an area of 114 sq. degrees (KiDS ESO-DR2). A comparison with publicly available Sloan Digital Sky Survey (SDSS)-based cluster catalogs shows that we match more than 50% of the clusters (77% in the case of the redMaPPer catalog). We also cross-matched our cluster catalog with the Abell clusters, and clusters found by XMM and in the Planck-SZ survey; however, only a small number of them lie inside the KiDS area currently available.Comment: 13 pages, 15 figures. Accepted for publication on Astronomy & Astrophysic