Development and testing of artificial membranes for rearing of Rhipicephalus microplus, the Southern Cattle Fever Tick

The southern cattle fever tick, Rhipicephalus microplus, is a livestock pest worldwide in tropical and subtropical climates, including South Texas, and can vector Babesia spp., the causal agents of bovine babesiosis. Artificial rearing methods for R. microplus are needed, especially for rearing specialist tick parasitoids that are under evaluation for classical biological control. In this study, we tested the efficiency of artificial feeding of R. microplus larvae, nymphs, and adults on a siliconized substrate (goldbeater’s membrane, lens paper, or Hemotek), or on nonsiliconized goldbeater’s membrane or Hemotek. Other variables tested were a warm water bath, incubator, positioning blood above or below ticks, using various attractants to stimulate attachment to membrane, incubating with or without 5% CO2, changing static blood once a day versus peristaltic pumping of blood, and using heparinized versus defibrinated blood. Peristaltic pumping of blood across the membrane inside the incubator significantly increased larval attachment. We found that up to 25% percent of these life stages would attach to the siliconized goldbeater’s membrane and feed, although none molted or completed their entire life cycle. A red color observable in the “fed” ticks’ legs seemed to indicate that bovine hemoglobin had penetrated the gut and entered the hemolymph of the ticks. We were successful rearing unfed nymphs to the engorged stage, which is the pre-requisite for rearing Ixoidiphagus tick parasitoids. Suggestions for future experimentation for rearing R. microplus on artificial membranes are discussed

Spectral UV measurements in Austria from 1994 to 2006: investigations of short- and long-term changes

The influence of variability of atmospheric parameters on short- and long-term changes of spectral UV irradiance measured at the Sonnblick observatory (47.03° N, 12.57° E, 3106 m) during the period from 1994 to 2006 is studied. Measurements were performed with the Brewer #093 single-monochromator spectrophotometer and with a Bentham DM 150 spectroradiometer (double-monochromator). <br> <br> The influence of ozone, albedo, snowline and clouds on UV variability is evaluated for each parameter separately using 10-year climatology. It is found that the effect of total ozone on short-term variability of UV irradiance at 305 nm can be more than 200% and on average more than 50%. Clouds can cause variability of 150% or more and on average 35%. Variability caused by albedo reaches a maximum of 32% in April (6% on average). In summer and autumn, total ozone and clouds strongly influence the variability of UV radiation, whereas in winter and spring ozone has the more pronounced effect. A decrease in snowline height from 3000 m to 800 m a.s.l. enhances the UV irradiance by a factor of 1.24 for clear sky conditions and by a factor of 1.7 for 8/8 cloud cover. <br> <br> Long-term trends are investigated for the time period from 1994 to 2006 based on clear-sky measurements, using the non-parametric Mann-Kendall trend test. Significant downward trends (99% confidence level) are found for solar zenith angle 55° at wavelengths from 305 nm to 324 nm and erythemally weighted irradiance according to CIE, which are caused by an increase in sunshine duration during periods of high total column ozone. Significant trends (90% confidence level) were also found for other combinations of wavelength and SZA

Biotic and abiotic factors influencing infestation levels of the arundo leafminer, Lasioptera donacis, in its native range in Mediterranean Europe

Lasioptera donacis is a biological control agent of Arundo donax, which is an invasive weed in the riparian hab-itats of the Rio Grande Basin of Texas and Northern Mexico. Field research was conducted in the native range of L. donacis in Mediterranean Europe to evaluate the biotic and abiotic factors that influence its local infestation levels. Lasioptera donacis feeding damage was documented on 40.4 and 67.8 % of dead and decaying leaf sheaths respectively across all sites. Lasioptera donacis was active in all locations including highly disturbed sites, but showed a slight preference for sites near running freshwater sources and lower infestation levels adjacent to salt water sources. The environmental preferences of L. donacis in Europe are similar to conditions in the Rio Grande Basin and Southwestern U.S. where A. donax is invasive

Arthropod abundance and diversity in street trees of south Texas, USA

In urban areas, street trees provide a variety of ecological services, including biodiversity conservation. In this study we examined arthropod diversity on native and non-native street trees sampled during the fall of 2010 and spring of 2011 in McAllen, Texas, one of the most rapidly growing urban areas in the country. Eighty-eight street trees were sampled by removing arthropods from the lower canopy foliage using a hand held vacuum. Arthropods were collected into nylon bags, identified to order, and counted by morphospecies. Overall, street trees supported a significant and diverse population of arthropods: a total of 1,971 arthropods were collected, from which 12 different orders and 102 different morphospecies were identified. We found arthropod abundance was higher on street trees native to the Lower Rio Grande Valley compared to non-native trees, especially for beetles, wasps, bees, ants, and spiders. This difference was particularly striking in spring when trees were flushed with new growth. The significant deficiency of arthropods on non-native trees is indicative of their relatively low value for maintaining entomological fauna. Local land managers who aim to include biodiversity conservation in their efforts thus should enhance the urban forest through the conservation of existing native remnant trees and promoting the use of native tree species in landscaping

The impact of omega-3 fatty acid use on the risk of atrial fibrillation in patients with cardiovascular disease

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Renormalized Harmonic-Oscillator Description of Confined Electron Systems with Inverse-Square Interaction

An integrable model for SU($\nu$) electrons with inverse-square interaction is studied for the system with confining harmonic potential. We develop a new description of the spectrum based on the {\it renormalized harmonic-oscillators} which incorporate interaction effects via the repulsion of energy levels. This approach enables a systematic treatment of the excitation spectrum as well as the ground-state quantities.Comment: RevTex, 7 page

Incidence of the Brown dog tick, Rhipicephalus sanguineus and its parasitoid, Ixodiphagus hookeri on dogs in South Texas

The southern cattle fever tick, Rhipicephalus microplus, is a livestock pest worldwide, including South Texas, and can vector Babesia spp.; the causal agents of bovine babesiosis. Its congener, the brown dog tick, Rhipicepha-lus sanguineus, is also common worldwide and is frequently parasitized by a wasp, Ixodiphagus hookeri. To better understand the life history and host location cues of parasitic wasps of ticks, which supports the cattle fever tick eradication program for R. microplus, we examined the incidence of R. sanguineus and its parasitoid I. hookeri. Dogs in Hidalgo County, TX were observed (n=624) from Oct 2018 to April 2019. Our results show that the sampled dogs had very low levels of R. sanguineus (1.89%) with 219 nymphs, and no parasitoids were recovered. We also found that R. sanguineus nymph incidence is significantly higher on female dogs and puppies than other classes of dogs

Horticultural technique for rearing and redistribution of the sessile biological control agent, Rhizaspidiotus donacis on its host plant, Arundo donax

Arundo donax, giant reed is an invasive weed in the riparian habitats of the Rio Grande Basin. A biological control program using specialist insects from the native range in Mediterranean Europe, including the arundo scale, Rhi-zaspidiotus donacis has been implemented. The arundo scale is a sessile insect that spends most of its life cycle affixed to its host plant, thus creating challenges for its rearing and redistribution to field sites. A horticultural technique was developed which allowed for rearing of the scale on small, potted A. donax microplants, which could later be transplanted to field sites. Female scale reach maturity on the microplants and produce mobile crawler scale, which move to adjacent uninfested A. donax plants. Arundo scale were established at 48 sites on the Rio Grande using microplants. This horticultural technique allows for movement of the arundo scale at any stage of its life cycle to field sites to conduct biological control programs for A. donax where it is invasive

A Combine On-Line Acoustic Flowmeter and Fluorocarbon Coolant Mixture Analyzer for The ATLAS Silicon Tracker

An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) to a blend containing 10-30% of C2F6 (hexafluoro-ethane) to reduce the evaporation temperature and better protect the silicon from cumulative radiation damage with increasing LHC luminosity. Central to this upgrade is a new acoustic instrument for the real-time measurement of the C3F8/C2F6 mixture ratio and flow. The instrument and its Supervisory, Control and Data Acquisition (SCADA) software are described in this paper. The instrument has demonstrated a resolution of 3.10-3 for C3F8/C2F6 mixtures with ~20%C2F6, and flow resolution of 2% of full scale for mass flows up to 30gs-1. In mixtures of widely-differing molecular weight (mw), higher mixture precision is possible: a sensitivity of < 5.10-4 to leaks of C3F8 into the ATLAS pixel detector nitrogen envelope (mw difference 160) has been seen. The instrument has many potential applications, including the analysis of mixtures of hydrocarbons, vapours for semi-conductor manufacture and anaesthesia