Statistics of Cosmological Black Hole Jet Sources: Blazar Predictions for GLAST

A study of the statistics of cosmological black-hole jet sources is applied to EGRET blazar data, and predictions are made for GLAST. Black-hole jet sources are modeled as collimated relativistic plasma outflows with radiation beamed along the jet axis due to strong Doppler boosting. The comoving rate density of blazar flares is assumed to follow a blazar formation rate (BFR), modeled by analytic functions based on astronomical observations and fits to EGRET data. The redshift and size distributions of gamma-ray blazars observed with EGRET, separated into BL Lac object (BL) and flat spectrum radio quasar (FSRQ) distributions, are fit with monoparametric functions for the distributions of the jet Lorentz factor \Gamma, comoving directional power l'_e, and spectral slope. A BFR factor ~10 x greater at z ~ 1 than at present is found to fit the FSRQ data. A smaller comoving rate density and greater luminosity of BL flares at early times compared to the present epoch fits the BL data. Based on the EGRET observations, ~1000 blazars consisting of ~800 FSRQs and FR2 radio galaxies and ~200 BL Lacs and FR1 radio galaxies will be detected with GLAST during the first year of the mission. Additional AGN classes, such as hard-spectrum BL Lacs that were mostly missed with EGRET, could add more GLAST sources. The FSRQ and BL contributions to the EGRET gamma-ray background at 1 GeV are estimated at the level of ~10 - 15% and ~2 - 4%, respectively. EGRET and GLAST sensitivities to blazar flares are considered in the optimal case, and a GLAST analysis method for blazar detection is outlined.Comment: 17 pages, 9 figures, ApJ, in press, v.660, May 1, 2007 (minor changes from previous version

Drugs In the Workplace: A Manager\u27s Guide

Drugs in the workplace is a growing problem that threatens a valuable human resource - the employee. Managers in the hospitality industry can take a proactive stance in meeting the problem head on. The authors discuss what managers can do

INTESTINAL PARASITISM AMONG JIREN ELEMENTARY AND JUNIOR SECONDARY SCHOOL STUDENTS IN SOUTH-WESTERN ETmOPIA

ABSTRACT: A cross-sectional survey on intestinal parasites was conducted in Jiren Elementary & Junior Secondary School, Jirnrna. A total of 301 stool specimens were collected by systematic random sampling from a total of 1626 population. The stools were examined for ova and parasites by direct saline suspension (wet mount) method. The result showed high prevalence rate of parasitic infection (68.4%). A total of 10 species were identified among which Ascaris lumbricoides was the leading (52.2%) followed by Triclluris trichiura (18.6%), while Schistosoma mansoni was the least (0.3 % ) .No statistically significant difference was seen in the prevalence rate of intestinal parasites by sex, (p>0.01). However, there is significant association between water source for drinking and parasitoses, (p < 0.01), where, unprotected source of water favouring infection of all infected. Most of the infected children (92.2%) were asymptomatic. It is suggested that affective PHC strategies, such as health education in schools, expansion of school health services and chemotherapy with broad spectrum anti- helrninthics should be (implimented). [Ethiop. i. Health Dev. 1994;8(1):37-41

The QSO evolution derived from the HBQS and other complete QSO surveys

An ESO Key programme dedicated to an Homogeneous Bright QSO Survey (HBQS) has been completed. 327 QSOs (Mb<-23, 0.3<z<2.2) have been selected over 555 deg^2 with 15<B<18.75. For B<16.4 the QSO surface density turns out to be a factor 2.2 higher than what measured by the PG survey, corresponding to a surface density of 0.013+/-.006 deg^{-2}. If the Edinburgh QSO Survey is included, an overdensity of a factor 2.5 is observed, corresponding to a density of 0.016+/-0.005 deg^{-2}. In order to derive the QSO optical luminosity function (LF) we used Monte Carlo simulations that take into account of the selection criteria, photometric errors and QSO spectral slope distribution. The LF can be represented with a Pure Luminosity Evolution (L(z)\propto(1+z)^k) of a two power law both for q_0=0.5 and q_0=0.1. For q_0=0.5 k=3.26, slower than the previous Boyle's (1992) estimations of k=3.45. A flatter slope beta=-3.72 of the bright part of the LF is also required. The observed overdensity of bright QSOs is concentrated at z<0.6. It results that in the range 0.3<z<0.6 the luminosity function is flatter than observed at higher redshifts. In this redshift range, for Mb<-25, 32 QSOs are observed instead of 19 expected from our best-fit PLE model. This feature requires a luminosity dependent luminosity evolution in order to satisfactorily represent the data in the whole 0.3<z<2.2 interval.Comment: Invited talk in "Wide Field Spectroscopy" (20-24 May 1996, Athens), eds. M. Kontizas et al. 6 pages and 3 eps figures, LaTex file, uses epfs.sty and crckapb.sty (included

Forage Bermudagrass: Selection, Establishment and Management

8 pp., 1 drawing, 6 tablesHybrid bermudagrass can produce high-quality forage, but as with any other crop, proper variety selection, soil preparation, planting, fertility, irrigation management, and timing of harvest are necessary to ensure the highest quality feed. This publication offers information on selecting the most suitable variety of bermudagrass; preparing the land; planting seed, sprigs, stolons, or tops; renovating bermudagrass fields; and managing and harvesting the crop

A review of studies on micellar enhanced ultrafiltration for heavy metals removal from wastewater

ABSTRACT Micellar enhanced ultrafiltration (MEUF) process has been used for the removal of copper, chromate, zinc, nickel, cadmium, serinium, arsenate and organics like phenol, o-cresol. This paper reviews various factors such as operating pressure, surfactant concentration, pH of solution, temperature, presence of non-ionic surfactant and salt, membrane type and its pore size and some inhibiting additives, competing metals on heavy metals and surfactants removals in the MEUF process. In this process, heavy metals removal reached over 99% at the initial concentration of up to 1 mM. Metals removal was enhanced by combining the MEUF treatment with electrolysis or with powdered activated carbon (PAC). Cetylperidinium Chloride (CPC) and Sodium dodecyl sulphate (SDS) surfactants removal from the MEUF permeate was also enhanced by the MEUF-ACF (activated carbon fibre) combined treatment. Surfactant has been recovered from the MEUF retentate solution by treating the retentate with HNO 3 , H 2 SO 4 , HCl, NaOH solution but retentate solution needs further treatment. Electrolysis was found better in the separation of metal and surfactant from the MEUF retentate solution. Further study on MEUF process is required for prolonging the experimental period for the heavy metals removal from wastewater. Investigation is also needed to treat highly concentrated solution, and to treat real wastewater

Emergency Alternative Crops for South Texas

8 pp., 2 tablesWhen hail, drought, flooding or untimely freezes destroy an established crop, planting an emergency alternative crop may be the producer's only hope for a profitable season. This publication helps producers determine which alternative crop is the best choice. Details are provided on soybeans, various types of peas, alyce clover, sorghums and other crops

Managing For High-quality Hay

4 pp., 4 tables, 1 figureThis publication highlights the factors determining hay quality and discusses fertility and water interaction, harvesting, quality losses and storage losses