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A Guide to the Larvae of the Nearctic Diamesinae (Diptera:Chironomidae) the Genera Boreoheptagyia, Protanypus, Diamesa, and Pseudokiefferiella

Description: From introduction: This review represents a consolidation of larval information not heretofore available in English. It utilizes modern nomenclature and keys the larvae of nine genera of the three above mentioned tribes (Protanypus, Boreoheptagyia and Diamesa).
Date: 1983
Creator: Doughman, Jan S.
Partner: UNT Libraries Government Documents Department

Spring Food Habits of Corydalus Cornutus L. in the Brazos River, Texas

Description: The objective of this study was to determine the kinds and numbers of food organisms consumed by Corydalus cornutus, and to investigate its periodicity of feeding during the spring months in the Brazos River, Palo Pinto County, Texas. A total of 468 larvae were collected at two-week intervals from February 29 to May 14, 1971. Larvae were taken at opportunity during three periods of the day, 6am.-12pm., 12pm.-6pm., and 6pm.-12am. A total of 23 different food items was observed in the 121 stomachs containing food. An expedient method of dissection of the digestive tract is included.
Date: August 1971
Creator: Friday, Gary P.
Partner: UNT Libraries

Powder-Post Damage by Lyctus Beetles to Seasoned Hardwood

Description: "The sapwood of seasoned hardwood material of all kinds, both finished and unfinished, especially of hickory, ash, and oak, is often ruined by yellowish-white grubs from one-eighth to one-fifth inch in length which burrow through the solid wood in all directions and convert it into powder. These grubs are the young, or larvae, of small, slender, somewhat flattened, reddish-brown to nearly black beetles, known as powder-post beetles.... The object of this bulletin is to describe the methods which have been found effective in preventing these losses and to induce a more general adoption of them throughout the United States as well as to show the character and extent of the damage." -- title page
Date: 1917
Creator: Hopkins, A. D. & Snyder, Thomas Elliott, b. 1885
Partner: UNT Libraries Government Documents Department

Evaluation of the Economic, Social, and Biological Feasibility of Bioconverting Food Wastes with the Black Soldier Fly (Hermetia illucens)

Description: Food waste in the waste stream is becoming an important aspect of integrated waste management systems. Current efforts are composting and animal feeding. However, these food waste disposal practices rely on slow thermodynamic processes of composting or finding farmers with domestic animals capable of consuming the food wastes. Bioconversion, a potential alternative, is a waste management practice that converts food waste to insect larval biomass and organic residue. This project uses a native and common non-pest insect in Texas, the black soldier fly, which processes large quantities of food wastes, as well as animal wastes and sewage in its larval stage. The goal of this research is to facilitate the identification and development of the practical parameters of bioconversion methods at a large cafeteria. Three major factors were selected to evaluate the practicality of a bioconversion system: (1) the biological constraints on the species; (2) the economic costs and benefits for the local community; (3) the perception of and interaction between the public and management agencies with respect to the bioconversion process. Results indicate that bioconversion is feasible on all levels. Larvae tolerate and consume food waste as well as used cooking grease, reducing the overall waste volume by 30-70% in a series of experiments, with an average reduction of 50%. The economical benefits are reduced collection costs and profit from the sale of pupae as a feedstuff, which could amount to as much as $1,200 per month under optimal conditions. Social acceptance is possible, but requires education of the public, specifically targeting school children. Potential impediments to social acceptance include historical attitudes and ignorance, which could be overcome through effective educational efforts.
Date: August 2004
Creator: Barry, Tami
Partner: UNT Libraries

The Catalpa Sphinx

Description: This report discusses the catalpa sphinx, a moth which in its larval or caterpillar stage of development is highly destructive to trees. Special attention is given to a discussion of this insect's life cycle and natural enemies as well as measures for controlling it.
Date: 1916
Creator: Howard, L. O. (Leland Ossian), 1857-1950 & Chittenden, F. H. (Frank Hurlbut), 1858-1929
Partner: UNT Libraries Government Documents Department

[Project Summary: Offshore Petroleum Platforms: Functional Significance for Larval Fish Across Longituinal and Latitudinal Gradients]

Description: Summary describing the work completed at Louisiana State University Coastal Fisheries Institute for 'Offshore Petroleum Platforms: Functional Significance for Larval Fish Across Longituinal and Latitudinal Gradients'. It includes background information on the project funding and sponsorship, goals, methodology, and findings.
Date: June 2002
Creator: Coastal Fisheries Institute, Louisiana State University
Partner: UNT Libraries Government Documents Department

Effects of Triclosan, Triclocarban, and Caffeine Exposure on the Development of Amphibian Larvae.

Description: Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated in three developmental stages of X. laevis, and in one developmental stage of B. woodhousii woodhousii, and R. sphenocephala. For most tissue and lipid uptake values, a significant increase was observed as exposure concentration increased. Tissue and lipid BCF values were dependent upon both stage and species. Chronic and acute effects of caffeine were determined in X. laevis larvae. Acute 96-hour LC50 values in four developmental stages were > 75,000 ug L-1 caffeine and heart rates were significantly different at the two earliest developmental stages. Larvae chronically exposed to caffeine reached metamorphosis at the same time as controls. Changes in ...
Date: August 2009
Creator: Palenske, Nicole Marie
Partner: UNT Libraries

Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami

Description: This study determined the effect of hypoxia on air-breathing onset and physiological and morphological characters in larvae of the air breathing fishes Trichopodus trichopterus and Betta splendens. Larvae were exposed intermittently (12/12 h daily) to 20, 17, and 14 kPa of PO2 from 1 to 40 days post-fertilization. Survival, onset of air breathing, wet body mass, O2, Pcrit were measured every 5 dpf. Hypoxia advanced by 4 days, and delayed by 9 days, the onset of air breathing in Betta and Trichopodus, respectively. Hypoxia increased larval body length, wet mass, and labyrinth organ respiratory surface of Betta, but did not affect these factors in Trichopodus. Hypoxic exposure increased O2 by 50-100% at each day throughout larval development in Betta, but had no effect on larval Trichopodus. Hypoxia decreased Pcrit in Betta by 37%, but increased Pcrit in Trichopodus by 70%. Larval Betta reared in hypoxia showed a modified heart rate:opercular rate ratio (3:1 to 2:1), but these changes did not occur in Trichopodus. Compared to Betta, the blood of Trichopodus had a higher P50 and much smaller Bohr and Root effects. These interspecific differences are likely due to ecophysiological differences: Betta is a non- obligatory air-breather after 36 dpf with a slow lifestyle reflected in its low metabolism, while Trichopodus is an obligatory air-breather past 32 dpf with an athletic fast lifestyle and accompanying high metabolism.
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Date: December 2015
Creator: Mendez Sanchez, Jose Fernando
Partner: UNT Libraries

Identification of Larval Pacific Lampreys (Lampetra Tridentata), River Lampreys (L. Ayresi) and Western Brook Lampreys (L. Richardson) and Thermal Requirements of Early Life History Stages of Lampreys : Annual Report 2002.

Description: Two fundamental aspects of lamprey biology were examined to provide tools for population assessment and determination of critical habitat needs of Columbia River Basin lampreys (the Pacific lamprey, Lampetra tridentata, and the western brook lamprey, L. richardsoni). In particular: (1) we examined the usefulness of current diagnostic characteristics in identification of larval lampreys, specifically pigmentation patterns, and collected material for development of meristic and morphometric descriptions of early life stages of lampreys, and (2) we examined the effects of temperature on survival and development of early life stages of Columbia River Basin lampreys.
Date: February 1, 2003
Creator: Meeuwig, Michael H.
Partner: UNT Libraries Government Documents Department

Influence of parental swimming stamina on the cardiac and metabolic performance of larval zebrafish (Danio rerio).

Description: Superior swimming stamina in adult fish is presumably passed on to their offspring, but the ontogeny of the appearance of superior stamina and the requisite enhanced cardio-respiratory support for locomotion in larval fishes has not been determined. Is the expression of the suite of parental traits enabling superior swimming stamina in their offspring dependent upon their achieving juvenile/adult morphology, or does it appear earlier in their larvae? To answer this, adults were classified into three groups based on swimming stamina, followed by measurement of length, mass, and width. Larval offspring from the two parental groups -high stamina larvae (HSL) and low stamina larvae (LSL)- were reared at 27°C in aerated water (21% O2). Routine and active heart rate, routine and active mass specific oxygen consumption were recorded through 21dpf, and cost of transport (COT) and factorial aerobic scope were derived from oxygen consumption measurements. Routine heart rate at 2dpf of LSL was 164 ± 1 b·min-1, compared to only 125 ± 2 b·min-1 for HSL. Routine heart rate subsequently peaked at 203 ± 1 b·min-1 at 5dpf in the HSL group, compared to 207 ± 1 b·min-1, at 4dpf in the LSP larvae. Active heart rate at 5 dpf of LSL was 218 ± 2 b·min-1 compared to 216 ± 2 b·min-1 for HSL. Active heart rate increased slightly to 227 ± 2 b·min-1 for LSL before decreasing again, while active heart rate remained relatively constant for HSL. Routine O2 consumption at 2dpf of HSL was 0.09 μmol·mg-1·hr-1, compared to 0.03 μmol·mg-1·hr-1 in LSL. Routine O2 consumption subsequently peaked at 0.70 μmol·mg-1·hr-1 at 9dpf in the HSL, compared to 0.71 μmol·mg-1·hr-1, at 9dpf in the LSL. These values dramatically decreased before leveling off at around 0.20 μmol·mg-1·hr-1 and 0.15 μmol·mg-1·h-1, respectively. Active O2 consumption at 5dpf for HSL was 0.38 ...
Date: May 2007
Creator: Gore, Matthew R.
Partner: UNT Libraries

The Chalcis-Fly in Alfalfa Seed

Description: "The clover-seed chalcis fly which is generally termed the alfalfa-seed chalcis-fly by alfalfa-seed growers, has been increasing so rapidly that its destructive work is now causing a large annual loss, and in some sections even threatening the production of alfalfa seed.... This bulletin will serve to give the alfalfa-seed grower a general knowledge of the chalcis-fly, together with such information as will direct him in adopting measures for reducing the large annual loss due to it work." -- p. 1-2
Date: 1914
Creator: Urbahns, Theodore Dietrich, 1880-
Partner: UNT Libraries Government Documents Department

The True Clothes Moths

Description: This report discusses three types of clothes moths: the case-making clothes moth, the webbing (or Southern) clothes moth, and the tapestry moth. The larvae of all three moths are known to destroy carpet, fur, and wool. Each type of moth is discussed with regard to its characteristics and habits, and methods of controlling them are suggested.
Date: 1915
Creator: Marlatt, C. L.
Partner: UNT Libraries Government Documents Department

Morphological and physiological developmental consequences of parental effects in the chicken embryo (Gallus gallus domesticus) and the zebrafish larva (Danio rerio).

Description: Cardiac, metabolic and growth response of early-stage chicken embryos to perturbations in yolk environment was investigated. Also, effects of parental hypoxia exposure on hypoxia resistance, thermal tolerance and body length of zebrafish larvae were investigated. In the first study, thyroxine, triiodothyronine and testosterone produced differential effects on heart rate and development rate of chicken embryos during the first 4 days of development. Triiodothyronine caused a dose-dependent increase in heart rate when applied at 40 or 70 hours of age, while thyroxine caused a dose-dependent increase in heart rate when applied at 40 hours only. Testosterone and propyl-thiouracil (deiodinase antagonist) did not have an effect on heart rate. Development rate was not changed by thyroxine, triiodothyronine, testosterone or propyl-thiouracil, which suggested that heart rate changes did not result from changes in embryo maturity. In the second study, chicken embryos exposed to yolks of different bird species during early-stage embryonic development showed changes in heart rate, mass-specific oxygen consumption and body mass that scaled with the egg mass, incubation period length, and yolk triiodothyronine and testosterone levels of the species from which yolk was derived. In the third study, this phenomenon was investigated between layer and broiler chickens. Heart rate, oxygen consumption and body mass of broiler and layer embryos were significantly changed by a breed-specific change in yolk environment. Yolk triiodothyronine and testosterone concentrations of broiler and layer eggs did not suggest that these hormones were responsible for physiological and morphological changes observed. The final study demonstrated that hypoxia resistance and body lengths, but not thermal tolerance of zebrafish larvae was increased by parental hypoxia exposure.
Date: August 2008
Creator: Ho, Dao H.
Partner: UNT Libraries

Identification of Larval Pacific Lampreys (Lampetra Tridentata), River Lampreys (L. Ayresi) and Western Brook Lampreys (L. Richardsoni) and Thermal Requirements of Early Life History Stages of Lampreys : Annual Report 2001.

Description: Lampreys inhabit temperate regions in both the northern and southern hemispheres. Typically, lampreys spawn in fresh water streams where, after hatching, larval lampreys (ammocoetes) burrow into soft substrate and spend an extended larval period filtering particulate matter from the water column. During this larval period, lampreys are characterized by greatly reduced subcutaneous eyes, reduced fins, unidirectional flow of water from the mouth through the gill pores for filter feeding, and the absence of tooth-like keratin plates (the structure most often used to differentiate lamprey species). After approximately three to seven years (Hardisty and Potter 1971a) lampreys go through a metamorphosis marked by drastic physiological and morphological changes. The resulting juvenile lampreys exhibit fully developed eyes, fins, and characteristic dentition patterns.
Date: January 1, 2002
Creator: Meeuwig, Michael H.
Partner: UNT Libraries Government Documents Department

Identification of Larval Pacific Lampreys (Lampetra tridentata), River Lampreys (L. ayresi), and Western Brook Lampreys (L. richardsoni) and Thermal Requirements of Early Life History Stages of Lampreys, Annual Report 2002-2003.

Description: Two fundamental aspects of lamprey biology were examined to provide tools for population assessment and determination of critical habitat needs of Columbia River Basin (CRB) lampreys (the Pacific lamprey, Lampetra tridentata, and the western brook lamprey, L. richardsoni). We evaluated the usefulness of current diagnostic characteristics for identification of larval lampreys (i.e., pigment patterns) and collected material for development of meristic and morphometric descriptions of early life stage CRB lampreys, and we determined the effects of temperature on survival and development of early life stage CRB lampreys. Thirty-one larval lampreys were collected from locations throughout the CRB and transported to the Columbia River Research Laboratory. Lampreys were sampled at six-week intervals at which time they were identified to the species level based on current diagnostic characteristics. Sampling was repeated until lampreys metamorphosed, at which time species identification was validated based on dentition, or until they died, at which time they were preserved for genetic examination. These lampreys were sampled 30 times with two individuals metamorphosing, both of which were consistently identified, and subsequently validated, as Pacific lampreys. Of the remaining lampreys, only one was inconsistently identified (Pacific lamprey in 83% of the sampling events and western brook lamprey in 17% of the sampling events). These data suggest that pigmentation patterns do not change appreciably through time. In 2001 and 2002 we artificially spawned Pacific and western brook lampreys in the laboratory to provide material for meristic and morphometric descriptions. We collected, digitized, preserved, and measured the mean chorion diameter of Pacific and western brook lamprey embryos. Embryos ranged in development from 1 d post fertilization to just prior to hatch, and were incubated at 14 C. Mean chorion diameter was greater and more variable for Pacific lampreys (mean {+-} SD; 1.468 {+-} 0.107 mm, N = 320) than for western ...
Date: January 1, 2004
Creator: Meeuwig, Michael
Partner: UNT Libraries Government Documents Department

Global F-theory GUTs

Description: We construct global F-theory GUT models on del Pezzo surfaces in compact Calabi-Yau fourfolds realized as complete intersections of two hypersurface constraints. The intersections of the GUT brane and the flavour branes as well as the gauge flux are described by the spectral cover construction. We consider a split S[U(4) x U(1){sub X}] spectral cover, which allows for the phenomenologically relevant Yukawa couplings and GUT breaking to the MSSM via hypercharge flux while preventing dimension-4 proton decay. General expressions for the massless spectrum, consistency conditions and a new method for the computation of curvature-induced tadpoles are presented. We also provide a geometric toolkit for further model searches in the framework of toric geometry. Finally, an explicit global model with three chiral generations and all required Yukawa couplings is defined on a Calabi-Yau fourfold which is fibered over the del Pezzo transition of the Fano threefold P{sup 4}.
Date: August 26, 2010
Creator: Blumenhagen, Ralph; /Munich, Max Planck Inst.; Grimm, Thomas W.; U., /Bonn; Jurke, Benjamin; /Munich, Max Planck Inst. et al.
Partner: UNT Libraries Government Documents Department