Effect of Temperature on Development Rate and Survival of \u3ci\u3eNomophila Nearctica\u3c/i\u3e (Lepidoptera: Pyralidae)

Development of Nomophila nearctica was studied under six constant tempera- tures in controlled temperature cabinets. Developmental threshold temperatures for egg, larval, and prepupal-pupal stages were 8.9, 1l.5, and 9.2°C. The overall mean developmental threshold temperature for all stages was 9.9°C. Degree-day summa- tions, based on the above threshold temperatures, averaged 50, 304, and 181 DD for the egg, larval, and prepupal-pupal stages, respectively. Total heat units of 535 DD are required for development from oviposition to adult emergence. Head capsule measurements indicated six larval instars

A Laboratory Infection of Alfalfa Weevil, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae), Larvae With the Fungal Pathogen \u3ci\u3eZoophthora Phytonomi\u3c/i\u3e (Zygomycetes: Entomophthoraceae)

Larvae of the alfalfa weevil, Hypera postica, were infected by an in vitro colony of Zoophthora phytonomi. Two spore types (infective conidia, and resting spores) were produced from infection trials. The spore type produced may be influenced by the physiological state of the larvae. Trials using field collected larvae which would produce diapausing adults formed both conidia and resting spores. Trials using larvae from a nondiapausing colony, however, formed only resting spores

Variance and Skewness in the FIRST survey

We investigate the large-scale clustering of radio sources in the FIRST 1.4-GHz survey by analysing the distribution function (counts in cells). We select a reliable sample from the the FIRST catalogue, paying particular attention to the problem of how to define single radio sources from the multiple components listed. We also consider the incompleteness of the catalogue. We estimate the angular two-point correlation function $w(\theta)$, the variance $\Psi_2$, and skewness $\Psi_3$ of the distribution for the various sub-samples chosen on different criteria. Both $w(\theta)$ and $\Psi_2$ show power-law behaviour with an amplitude corresponding a spatial correlation length of $r_0 \sim 10 h^{-1}$Mpc. We detect significant skewness in the distribution, the first such detection in radio surveys. This skewness is found to be related to the variance through $\Psi_3=S_3(\Psi_2)^{\alpha}$, with $\alpha=1.9\pm 0.1$, consistent with the non-linear gravitational growth of perturbations from primordial Gaussian initial conditions. We show that the amplitude of variance and skewness are consistent with realistic models of galaxy clustering.Comment: 13 pages, 21 inline figures, to appear in MNRA

Comment on 'Quantum Backreaction on "Classical" Variables'

It is argued that the bracket of Anderson's canonical theory should have been antisymmetric otherwise serious controversies arise like violation of both hermiticity and the Leibniz rule of differentiation.Comment: 3 pages, LaTe

Disease as a Larval Mortality Factor in Alfalfa Weevil, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae) Populations in Illinois

During the 1974 growing season, larvae of the alfalfa weevil, Hypera postica (Gyllenhal), were examined for pathogens. Three larvae out of 715 examined were infected with a microsporidium. This infection was present in both Washington and Mason counties in Illinois

Epizootiology of the Fungal Pathogen, \u3ci\u3eZoophthora Phytonomi\u3c/i\u3e (Zygomycetes: Entomophthorales) in Field Populations of Alfalfa Weevil (Coleoptera: Curculionidae) Larvae in Illinois

The influence of the fungal pathogen, Zoophthora phytonomi, on larvae of the alfalfa weevil, Hypera postica, was studied in three alfalfa fields in Illinois. Disease epizootics occurred in all three fields and disease onset was ob- served within a fairly narrow range of degree day accumulations. At the height of each epizootic, percentages of infected larvae were between 80 and 100%, and the fungus contributed to the collapse of the weevil population in each field. Percent parasitism by the larval parasitoids, Bathyplectes cur­culionis and B. anurus, was lower in our fields than is common in mid-season alfalfa weevil populations and was sometimes correlated negatively with Zoophthora phytonomi infection levels, strongly implying negative interfer- ence between the parasitoids and the pathogen. Control potential of Zooph­thora phytonomi disease in alfalfa weevil larval populations is addressed

A New Microsporidium in Alfalfa Weevil Populations: Distribution and Characterization

A microsporidium species, not previously reported, was found infecting field populations of the alfalfa weevil, Hypera postica, in Illinois. The pathogen is widely distributed thoughout the state. Percent infection ranged from 1 % to 50% at different collection locations. Characteristics of the microsporidium and possible modes of transmission are presented

The Redshift Distribution of FIRST Radio Sources at 1 mJy

We present spectra for a sample of radio sources from the FIRST survey, and use them to define the form of the redshift distribution of radio sources at mJy levels.We targeted 365 sources and obtained 46 redshifts (13 per cent of the sample). We find that our sample is complete in redshift measurement to R $\sim 18.6$, corresponding to $z\sim 0.2$. Early-type galaxies represent the largest subset (45 per cent) of the sample and have redshifts 0.15\la z \la 0.5 ; late-type galaxies make up 15 per cent of the sample and have redshifts 0.05\la z \la 0.2; starbursting galaxies are a small fraction ($\sim 6$ per cent), and are very nearby (z\la 0.05). Some 9 per cent of the population have Seyfert1/quasar-type spectra, all at z\ga 0.8, and there are 4 per cent are Seyfert2 type galaxies at intermediate redshifts ($z\sim 0.2$). Using our measurements and data from the Phoenix survey, we obtain an estimate for $N(z)$ at $S_{1.4 \rm {GHz}}\ge 1$ mJy and compare this with model predictions. At variance with previous conclusions, we find that the population of starbursting objects makes up \la 5 per cent of the radio population at S $\sim 1$ mJy.Comment: 20 pages, sumbitted to MNRA

Radio Sources in the 2dF Galaxy Redshift Survey. I. Radio Source Populations

We present the first results from a study of the radio continuum properties of galaxies in the 2dF Galaxy Redshift Survey, based on thirty 2dF fields covering a total area of about 100 square degrees. About 1.5% of galaxies with b(J) < 19.4 mag are detected as radio continuum sources in the NRAO VLA Sky Survey (NVSS). Of these, roughly 40% are star-forming galaxies and 60% are active galaxies (mostly low-power radio galaxies and a few Seyferts). The combination of 2dFGRS and NVSS will eventually yield a homogeneous set of around 4000 radio-galaxy spectra, which will be a powerful tool for studying the distriibution and evolution of both AGN and starburst galaxies out to redshift z=0.3.Comment: 14 pages, 7 figures, accepted for publication in PAS