522 research outputs found
Biology and Management of the American Shad and Status of the Fisheries, Atlantic Coast of the United States, 1960
This paper summarizes current information on the American shad, Alosa sapidissima, and describes the species and its fishery. Emphasis is placed on (1) life history of the fish, (2) condition of the fishery by State and water areas in 1960 compared to 1896 when the last comprehensive description was made, (3) factors responsible for decline in abundance, and (4) management measures.
The shad fishery has changed little over the past three-quarters of a century, except in magnitude of yield. Types of shad-fishing gear have remained relatively unchanged, but many improvements have been made in fishing techniques, mostly to achieve economy.
In 1896 the estimated catch was more than 50 million pounds. New Jersey ranked first in production with about 14 million pounds, and Virginia second with 11 million pounds. In 1960 the estimated catch was slightly more than 8 million pounds. Maryland ranked first in production with slightly more than 1.5 million pounds, Virginia second with slightly less than 1.4 million pounds, and North Carolina third with about 1.3 million pounds.
Biological and economic factors blamed for the decline in shad abundance, such as physical changes in the environment, construction of dams, pollution, over-fishing, and natural cycles of abundance, are discussed. Also discussed are methods used for the rehabilitation and management of the fishery, such as artificial propagation, installation of fish-passage facilities at impoundments, and fishing regulations.
With our present knowledge, we can manage individual shad populations; but, we probably cannot restore the shad to its former peak of abundance
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Dosimetric comparison study between intensity modulated radiation therapy and three-dimensional conformal proton therapy for pelvic bone marrow sparing in the treatment of cervical cancer.
The objective was to compare intensity-modulated radiation therapy (IMRT) with 3D conformal proton therapy (3DCPT) in the treatment of cervical cancer. In particular, each technique's ability to spare pelvic bone marrow (PBM) was of primary interest in this study. A total of six cervical cancer patients (3 postoperative and 3 intact) were planned and analyzed. All plans had uniform 1.0 cm CTV-PTV margin and satisfied the 95% PTV with 100% isodose (prescription dose = 45 Gy) coverage. Dose-volume histograms (DVH) were analyzed for comparison. The overall PTV and PBM volumes were 1035.9 ± 192.2 cc and 1151.4 ± 198.3 cc, respectively. In terms of PTV dose conformity index (DCI) and dose homogeneity index (DHI), 3DCPT was slightly superior to IMRT with 1.00 ± 0.001, 1.01 ± 0.02, and 1.10 ± 0.02, 1.13 ± 0.01, respectively. In addition, 3DCPT demonstrated superiority in reducing lower doses (i.e., V30 or less) to PBM, small bowel and bladder. Particularly in PBM, average V10 and V20 reductions of 10.8% and 7.4% (p = 0.001 and 0.04), respectively, were observed. However, in the higher dose range, IMRT provided better sparing (> V30). For example, in small bowel and PBM, average reductions in V45 of 4.9% and 10.0% (p = 0.048 and 0.008), respectively, were observed. Due to its physical characteristics such as low entrance dose, spread-out Bragg peak and finite particle range of protons, 3DCPT illustrated superior target coverage uniformity and sparing of the lower doses in PBM and other organs. Further studies are, however, needed to fully exploit the benefits of protons for general use in cervical cancer
Research and Development of Automated Eddy Current Testing for Composite Overwrapped Pressure Vessels
Eddy current testing (ET) was used to scan bare metallic liners used in the fabrication of composite overwrapped pressure vessels (COPVs) for flaws which could result in premature failure of the vessel. The main goal of the project was to make improvements in the areas of scan signal to noise ratio, sensitivity of flaw detection, and estimation of flaw dimensions. Scan settings were optimized resulting in an increased signal to noise ratio. Previously undiscovered flaw indications were observed and investigated. Threshold criteria were determined for the system software's flaw report and estimation of flaw dimensions were brought to an acceptable level of accuracy. Computer algorithms were written to import data for filtering and a numerical derivative filtering algorithm was evaluated
Pesticide Ground Water Monitoring Project Phase VIII
During Phase VIII monitoring (March 24, 2000 to June 30, 2001 ), 86 samples were collected from 77 new wells and 9 samples were collected from wells with previous detectable herbicide
The Effects of Medium Chain Fatty Acids in Mash and Crumbled Pellet Diets on Growth Performance of Broilers
The objective of this experiment was to determine the effects of medium chain fatty acids (MCFA) in mash and crumbled pellet broiler diets. A total of 400 male chicks (Cobb 500; initial BW 0.092 lb) were housed in 4 Petersime batteries and used in an 18-d study. Treatments were randomly assigned to 80 cages within location block resulting in 8 cages per treatment with 5 chicks per cage at placement. Treatments were arranged in a 2 × 5 factorial with main effects of feed type (mash and crumbled pellet) and 0.5% MCFA inclusion (no inclusion, control; hexanoic acid, C6; octanoic acid, C8; decanoic acid, C10; and dodecanoic acid, C12). Fat inclusions in the diets were equalized using 0.5% soybean oil in the control diet. Prior to crumbling, diets were conditioned at 185°F for approximately 20 s and pelleted (CPM, model CL-5, Crawfordsville, IN) with a 5/32 × 7/8 in. ring die. Dietary treatments were fed for the full duration of the study. There was no evidence of feed form × MCFA interactions. From d 0 to 18, chicks fed pelleted diets had improved (P \u3c 0.001) body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR), and final BW compared to those fed mash diets. For the overall treatment period, there was no evidence of a MCFA effect (P \u3e 0.10) on broiler performance. Pelleting and crumbling feed improved growth performance regardless of MCFA inclusion. The MCFA inclusion did not positively influence growth performance of broilers
FishFace: interactive atlas of zebrafish craniofacial development at cellular resolution
Background: The vertebrate craniofacial skeleton may exhibit anatomical complexity and diversity, but its genesis and evolution can be understood through careful dissection of developmental programs at cellular resolution. Resources are lacking that include introductory overviews of skeletal anatomy coupled with descriptions of craniofacial development at cellular resolution. In addition to providing analytical guidelines for other studies, such an atlas would suggest cellular mechanisms underlying development. Description We present the Fish Face Atlas, an online, 3D-interactive atlas of craniofacial development in the zebrafish Danio rerio. Alizarin red-stained skulls scanned by fluorescent optical projection tomography and segmented into individual elements provide a resource for understanding the 3D structure of the zebrafish craniofacial skeleton. These data provide the user an anatomical entry point to confocal images of Alizarin red-stained zebrafish with transgenically-labelled pharyngeal arch ectomesenchyme, chondrocytes, and osteoblasts, which illustrate the appearance, morphogenesis, and growth of the mandibular and hyoid cartilages and bones, as viewed in live, anesthetized zebrafish during embryonic and larval development. Confocal image stacks at high magnification during the same stages provide cellular detail and suggest developmental and evolutionary hypotheses. Conclusion: The FishFace Atlas is a novel learning tool for understanding craniofacial skeletal development, and can serve as a reference for a variety of studies, including comparative and mutational analyses
DREADDs in Drosophila: A Pharmacogenetic Approach for Controlling Behavior, Neuronal Signaling, and Physiology in the Fly
SummaryWe have translated a powerful genetic tool, designer receptors exclusively activated by designer drugs (DREADDs), from mammalian systems to Drosophila melanogaster to selectively, rapidly, reversibly, and dose-dependently control behaviors and physiological processes in the fly. DREADDs are muscarinic acetylcholine G protein-coupled receptors evolved for loss of affinity to acetylcholine and for the ability to be fully activated by an otherwise biologically inert chemical, clozapine-N-oxide. We demonstrate its ability to control a variety of behaviors and processes in larvae and adults, including heart rate, sensory processing, diurnal behavior, learning and memory, and courtship. The advantages of this particular technology include the dose-responsive control of behaviors, the lack of a need for specialized equipment, and the capacity to remotely control signaling in essentially all neuronal and nonneuronal fly tissues
Morphine self-administration, food-reinforced, and avoidance behaviors in rhesus monkeys
1. A fixed interval-fixed ratio chain of behavior was maintained for periods as long as 6 months by intravenously administered morphine.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46396/1/213_2004_Article_BF00413045.pd
Talking Points on Publicly Engaged Scholarship at IUPUI
Talking Points on Publicly Engaged Scholarship at IUPUI
Informed by Public Scholarship at Indiana University-Purdue University Indianapolis, a concept paper written by the Faculty Learning Community (FLC) on Public Scholarship and refined through ongoing FLC work between 2015-18 in collaboration with faculty across the campus and with nationally-recognized scholars
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