Poly(methyl methacrylate) synthetic grit formulations sustain the delivery of nicarbazin, a contraceptive agent, in pest waterfowl

Sixty-three mallards were fed one of ten poly(methyl methacrylate) based synthetic grit formulations containing varying concentrations of a proposed wildlife contraceptive (nicarbazin), plasticizer (acetyl tributylcitrate) and/or cross-linking agent (1,4-butanediol diacrylate). Release characteristics of the contraceptive agent were monitored for the purpose of developing a contraceptive formulation for control of pest waterfowl in urban settings. The addition of plasticizer increased the erosion rate (t1/2=0.97-2.85 days), cross-linking the polymer matrix slightly decreased the erosion rate (t1/2=4.45-5.05 days) and increasing the concentration of the contraceptive agent increased the erosion rate (t1/2= 3 . 3 and 9.9 days at 60% and 7.5% active ingredient. respectively). The larger and smaller grit pieces had longer half lives at 11.0 and 11.6 days, respectively while the mid sized grit had a half life of 4.95 days. Control grit had a half life of 12.7 days based on weight loss. Analysis of blood and feces for monitoring release from the grit and approximate indirect plasma levels of the active ingredient proved feasible

Poly(methyl methacrylate) synthetic grit formulations sustain the delivery of nicarbazin, a contraceptive agent, in pest waterfowl

Sixty-three mallards were fed one of ten poly(methyl methacrylate) based synthetic grit formulations containing varying concentrations of a proposed wildlife contraceptive (nicarbazin), plasticizer (acetyl tributylcitrate) and/or cross-linking agent (1,4-butanediol diacrylate). Release characteristics of the contraceptive agent were monitored for the purpose of developing a contraceptive formulation for control of pest waterfowl in urban settings. The addition of plasticizer increased the erosion rate (t1/2=0.97-2.85 days), cross-linking the polymer matrix slightly decreased the erosion rate (t1/2=4.45-5.05 days) and increasing the concentration of the contraceptive agent increased the erosion rate (t1/2= 3 . 3 and 9.9 days at 60% and 7.5% active ingredient. respectively). The larger and smaller grit pieces had longer half lives at 11.0 and 11.6 days, respectively while the mid sized grit had a half life of 4.95 days. Control grit had a half life of 12.7 days based on weight loss. Analysis of blood and feces for monitoring release from the grit and approximate indirect plasma levels of the active ingredient proved feasible

Determination of DiazaCon in Quail Feed and Quail Serum by Ion Pair Reversed-Phase Chromatography

Liquid chromatographic (LC) methods were developed for quantitating the potential avian contraceptive DiazaCon in quail feed and serum. DiazaCon was extracted from ground quail feed with basic n-butyl chloride. The n-butyl chloride extract was evaporated to dryness. The DiazaCon residues were dissolved in an aqueous methanolic ion pairing solution and quantitated by LC at 206 nm. Avian sera was combined with an equal volume of a pH 4 aqueous solution of ion pairing reagent and filtered to remove interfering proteins. DiazaCon was quantitated by LC. Mean recoveries for 500 and 2000 ppm fortified feed were 89.1 and 91.0%, respectively. The mean recovery for sera fortified at 5 levels ranging from 35 to 2000 ppm was 84.9%. Method limits of detection were approximately 14 and 13 ppm for feed and sera, respectively

Field Method for Analyzing Birds for Avicide 3-Chloro-P-Toluidine Hydrochloride

We developed a fast and simple method to detect presence or absence of DRC-1339 (CPTH: 3-Chloro-p-toluidine Hydrochloride) in birds that fed on DRC-1339 bait sites. We compared the effectiveness of the colorimetric method to the previously published analytical method using birds collected from DRC-1339 bait sites in Louisiana and Texas. We also conducted tests with caged red-winged blackbirds (Agelaius phoeniceus) to determine if time from consumption of DRC-1339-treated bait to death and time from death to colorimetric analysis affected test results. The colorimetric assay was effective in detecting the presence or absence of DRC-1339 in birds collected from bait sites. In the tests with caged birds, the method resulted in the detection of four grains of treated rice consumed up to 120 minutes post consumption, but failed to detect 1 grain of treated rice consumed at 120 minutes. Frozen samples of 4 treated consumed rice grains could be detected up to 90 days post collection

DEVELOPMENT OF A SYNTHETIC MATERIALS MIMIC FOR VULTURE OLFACTION RESEARCH

Since the early 1990\u27s, an increase in damage associated with the activities of black (Coragyps atratus) and turkey (Cathartes aura) vultures has been observed. These activities include extensive damage to real and personal property. Vultures display an affinity for objects made of synthetic materials such as vinyl or plastic, and frequently damage items such as seat cushions, roof shingles, and caulking sealant. To explore whether this behavior in vultures is olfactorily driven, volatile compounds emitted by 21 vulture-damaged objects were collected and analyzed using purge-and-trap gas chromatography/mass spectrometry. Results from these analyses were tabulated and the 27 most commonly occurring compounds were identified. Six of the vulture-damaged samples contained at least 23 of the 27 identified compounds, and hexanal, octanal, undecane, and nonanal were found in all 21 vulture-damaged samples. Using these data, a water-based emulsion containing the 27 most frequently observed compounds in the vulture-damaged samples was formulated to serve as a synthetic materials mimic (SMM). A sustained volatile release delivery system utilizing cellulose sponges was also developed, and used to deliver the SMM for bioassay trials examining the response of captive vultures to the SMM

Efficacy of ERL-4221 as an ovotoxin for feral pigs (\u3ci\u3eSus scrofa\u3c/i\u3e)

Context. The expansion of feral pig populations across the United States has increased the occurrence of damage and damage complaints.Newtechniques are needed to more effectively manage feral pig damage, including the development of fertility control agents. Aims. We aimed to assess the ovotoxic properties of ERL-4221 as a candidate fertility control agent for feral pigs. Methods. We conducted two palatability trials to determine ERL-4221 acceptance and one experimental trial with ERL- 4221 at the captive wildlife facility of Texas A&M University-Kingsville during 2008. Our experimental trial had three treatments, a control containing no ERL-4221, baits containing 16.0 mg ERL-4221 kg–1 bodyweight for 10 days, and baits containing 16.0 mg ERL-4221 kg–1 bodyweight for 20 days. Key results. Final body mass, total ovary mass, number of follicles and number of corpora lutea did not differ between treatments. Conclusions. We did not find it efficacious to orally deliver ERL-4221 to feral pigs to reduce fertility. Oral delivery is the most practical, cost-effective means of delivering fertility control agents to feral pigs and development of additional fertility control strategies are needed. Implications. Unless ovotoxic effects of ERL-4221 can be identified in feral pigs, along with a successful means of administration, other fertility control strategies may need to be explored, such as oocyte-secreted proteins that regulate follicular development

String-like Clusters and Cooperative Motion in a Model Glass-Forming Liquid

A large-scale molecular dynamics simulation is performed on a glass-forming Lennard-Jones mixture to determine the nature of dynamical heterogeneities which arise in this model fragile liquid. We observe that the most mobile particles exhibit a cooperative motion in the form of string-like paths (``strings'') whose mean length and radius of gyration increase as the liquid is cooled. The length distribution of the strings is found to be similar to that expected for the equilibrium polymerization of linear polymer chains.Comment: 6 pages of RevTex, 6 postscript figures, uses epsf.st

The Victorian Newsletter (Spring 1967)

The Victorian Newsletter is edited for the English X Group of the Modern Language Association by William E. Buckler, New York University, New York, N.Y. 10003

Regional Management Units for Marine Turtles: A Novel Framework for Prioritizing Conservation and Research across Multiple Scales

Background: Resolving threats to widely distributed marine megafauna requires definition of the geographic distributions of both the threats as well as the population unit(s) of interest. In turn, because individual threats can operate on varying spatial scales, their impacts can affect different segments of a population of the same species. Therefore, integration of multiple tools and techniques - including site-based monitoring, genetic analyses, mark-recapture studies and telemetry - can facilitate robust definitions of population segments at multiple biological and spatial scales to address different management and research challenges. Methodology/Principal Findings: To address these issues for marine turtles, we collated all available studies on marine turtle biogeography, including nesting sites, population abundances and trends, population genetics, and satellite telemetry. We georeferenced this information to generate separate layers for nesting sites, genetic stocks, and core distributions of population segments of all marine turtle species. We then spatially integrated this information from fine-to coarse-spatial scales to develop nested envelope models, or Regional Management Units (RMUs), for marine turtles globally. Conclusions/Significance: The RMU framework is a solution to the challenge of how to organize marine turtles into units of protection above the level of nesting populations, but below the level of species, within regional entities that might be on independent evolutionary trajectories. Among many potential applications, RMUs provide a framework for identifying data gaps, assessing high diversity areas for multiple species and genetic stocks, and evaluating conservation status of marine turtles. Furthermore, RMUs allow for identification of geographic barriers to gene flow, and can provide valuable guidance to marine spatial planning initiatives that integrate spatial distributions of protected species and human activities. In addition, the RMU framework - including maps and supporting metadata - will be an iterative, user-driven tool made publicly available in an online application for comments, improvements, download and analysis

Expression of NES-hTERT in Cancer Cells Delays Cell Cycle Progression and Increases Sensitivity to Genotoxic Stress

Telomerase is a reverse transcriptase associated with cellular immortality through telomere maintenance. This enzyme is activated in 90% of human cancers, and inhibitors of telomerase are currently in clinical trials to counteract tumor growth. Many aspects of telomerase biology have been investigated for therapy, particularly inhibition of the enzyme, but little was done regarding its subcellular shuttling. We have recently shown that mutations in the nuclear export signal of hTERT, the catalytic component of telomerase, led to a mutant (NES-hTERT) that failed to immortalize cells despite nuclear localization and catalytic activity. Expression of NES-hTERT in primary fibroblast resulted in telomere-based premature senescence and mitochondrial dysfunction. Here we show that expression of NES-hTERT in LNCaP, SQ20B and HeLa cells rapidly and significantly decreases their proliferation rate and ability to form colonies in soft agar while not interfering with endogenous telomerase activity. The cancer cells showed increased DNA damage at telomeric and extra-telomeric sites, and became sensitive to ionizing radiation and hydrogen peroxide exposures. Our data show that expression of NES-hTERT efficiently counteracts cancer cell growth in vitro in at least two different ways, and suggest manipulation with the NES of hTERT or its subcellular shuttling as a new strategy for cancer treatment