ABSTRACT
Soil and leaf populations of Bacillus thuringiensis (Bt) were monitored following aerial application of commercial Bt formulations at the rate of 72 billion international units per acre per year during a 5-year period. Data from soil sample spore counts suggested that Bt spores persisted in Wasatch forest soils for up to 2 years but they did not proliferate. Bt isolates were recovered from leaf samples 12 months post application from sprayed, previously sprayed and from nonsprayed areas. The frequency and diversity of Bt isolates recovered from leaves was independent of sample area spray history. In accordance with U.S. Forest Service criteria, aerial application of Bt during a 5-year period resulted in the eradication of gypsy moth (Lymantria dispar, L) from the Wasatch Front region of the Wasatch Mountain Range, Utah.
Subject(s)
Bacillus thuringiensis , Pesticide Residues , Spores, BacterialABSTRACT
The USDA Forest Service, even though a minor user of pesticides, has maintained an active program for understanding the performance, atomization, evaporation, efficacy, environmental fate, atmospheric dispersion, and environmental impact of chemical and biological insecticides. Since its self-imposed ban on use of dichloro diphenyl trichloroethane (DDT) in 1964, the USDA Forest Service has pursued insecticides that are less persistent and have reduced potential for impact on nontarget organisms, application technology that supports their efficient and efficacious use, and computer models that predict insecticide fate in the environment. This program has been active over the last 3 decades, beginning with research for chemical insecticide substitutes for DDT, progressing in time to biological insecticides and other biorational control agents. In our effort to make the less persistent insecticides work under forestry conditions, it was necessary to investigate insecticide monitoring, detection, and sampling methods; application systems; atmospheric influences; tank mixes and adjuvants; nozzles and atomization; evaporation; spray deposition and canopy penetration; biological response; and environmental fate. This paper reviews some of this work that might be applicable to mosquito control.
Subject(s)
Insect Control/methods , Insecticides , United States Department of Agriculture , Animals , United StatesABSTRACT
Flow of embolized carbonyl iron particles under the influence of a magnetic field was evaluated in vitro and in vivo. The magnetic force caused particles to form aggregates, obstructing tubing or vascular beds. In dogs, 0.5 cc of iron particles injectged into a renal artery under magnetic control caused total occlusion and necrosis; injection without magnetic control caused little damage and no change in function. There was little systemic toxicity. Injection of iron particles under magnetic control may be helpful in embolic arterial occlusion and localized irradiation, hyperthermia, and chemotherapy.
Subject(s)
Embolization, Therapeutic/methods , Iron , Magnetics , Organometallic Compounds , Animals , Diatrizoate , Dogs , In Vitro Techniques , Iron Carbonyl Compounds , Kidney/anatomy & histology , Kidney/diagnostic imaging , Kidney Diseases/therapy , Models, Biological , Rabbits , Radiography , Renal ArteryABSTRACT
Transcatheter hemostasis is applicable in a large variety of causes of genitourinary hemorrhage. The method is particularly useful in the management of trauma since temporary occlusion of the bleeding vessel usually produces cessation of hemorrhage without significant sacrifice of additional parenchyma. Control of arteriovenous fistulas requires an assessment of flow characteristics and careful tailoring of catheter and embolization technique; large emboli or glue is frequently required for occlusion of large fistulas, whereas small ones can be treated with Ivalon. Hemorrhage from renal or pelvic neoplasm is also effectively managed by transcatheter therapy.
Subject(s)
Embolization, Therapeutic/methods , Adenocarcinoma/therapy , Adult , Aged , Arteriovenous Fistula/therapy , Arteriovenous Malformations/therapy , Female , Hemorrhage/etiology , Hemorrhage/therapy , Humans , Kidney/injuries , Kidney Neoplasms/therapy , Male , Middle Aged , Pelvic Bones/injuries , Pelvis/blood supply , Renal Artery , Renal Veins , Urinary Catheterization/methods , Uterine Cervical Neoplasms/therapyABSTRACT
Colonic or ileal varices secondary to portal hypertension or superior mesenteric vein obstruction may present with significant hemorrhage which is difficult to diagnose by angiography. In a patient with lower gastrointestinal hemorrhage and colonic varices, a 99mTc-sulfur colloid scan demonstrated the varices and extravasation into the cecum. Extravasation was not demonstrable by angiography.
Subject(s)
Cecum/blood supply , Gastrointestinal Hemorrhage/diagnostic imaging , Varicose Veins/diagnostic imaging , Female , Gastrointestinal Hemorrhage/etiology , Humans , Middle Aged , Radionuclide Imaging , Varicose Veins/complicationsSubject(s)
Empty Sella Syndrome/diagnostic imaging , Adult , Female , Humans , Male , Tomography, X-Ray ComputedABSTRACT
A new free-standing library building, designed to integrate the collections serving interdisciplinary study in science and medicine, is described.