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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Symbola ad anatomiam vesicae natatoriae piscium ...

Berlak, Salomon, January 1834 (has links)
Inaug.-diss. Königsberg. / Vita.
2

Swim bladder morphology in chaetodontid butterflyfishes with a discussion of its bioacoustic significance

Woods, Christopher F. January 2006 (has links)
Thesis (M.S.)--Villanova University, 2006. / Biology Dept. Includes bibliographical references.
3

Argon-nitrogen ratios in the swimbladder of physostomous fishes with particular reference to the rainbow trout, Salmo gairdnerii

Buell, James Whitton, 1944- 06 1900 (has links)
ix, 128 leaves, : ill. Thesis (Ph.D.)--University of Oregon, 1973 Vita Bibliography: l. [122]-128
4

In vivo and in vitro studies on the metabolism of the swimbladder gas gland of the bluegill sunfish /

Deck, James Emerson January 1969 (has links)
No description available.
5

Swimbladder morphology and buoyancy of Northeastern Pacific myctophids

Butler, John Lawton 18 December 1970 (has links)
Of the common adult lanternfishes found off Oregon, two species have fat-invested swimbladders (Stenobrachius leucopsarus Eigenmann and Eigenmann 1890 and Stenobrachius nannochir Gilbert 1891), two species have reduced swimbladders (Lampanyctus ritteri Gilbert 1915 and Lampanyctus galis Gilbert 1891), two species have gas-filled swimbladders ((Protomyctophum thomp soni (Chapman 1944)) and (Protomyctophum crockeri (Bolin 1939)). Adult Diaphus theta Eigenrnann and Eigenmann 1891 and adult Tarletonbeania crenularis Jordan and Gilbert 1880 however, have either gas-filled or reduced swimbladders. Small individuals of all the above species have gas-filled swimbladders. The primary buoyancy mechanism is lipids for large S. leucopsarus, S. nannochir, L. ritteri andD. theta, is reduction of dense material for large L. regalis, and is gas for all juveniles and for P. thompsoni, P. crockeri and some adult T. crenularis and D. theta. / Graduation date: 1971
6

Rates of swim bladder parasite infection and PIT tag retention in upstream migrant American eels of the Upper Potomac River drainage

Zimmerman, Jennifer L. January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vii, 67 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references.
7

Some functions of the swimbladder and its ducts in Atlantic and Pacific herring

Brawn, Vivien Mavis January 1964 (has links)
The swimbladder of Atlantic and Pacific herring has a pneumatic duct arising from the stomach caecum and a direct posterior opening to the exterior. The thesis is advanced that these peculiarities are associated with differences in function which may be related to the life of the herring. Herring obtain swimbladder gas by swallowing air at the surface but not by secretion or bacterial gas generation over one week. Gas release from the swimbladder through the posterior duct occurs in response to pressure reduction, sympathomimetic drugs and atropine and is inhibited by spinal section or brain removal suggesting a gas release mechanism involving the central nervous system. Gas loss through the pneumatic duct is prevented by the swimbladder valve which opens in response to adrenalin. The swimbladder responds to adrenalin by moving its contained gas anteriorly and to pilocarpine by increasing internal gas pressure. The pneumatic duct, normally fluid filled, controls the applied pressure at which gas flow in either direction starts and finishes. This duct mechanically prevents the entry of particulate matter from the stomach and is able to remove air bubbles leaving a mean net force of 3.2 dynes/ml downwards to be compensated for by movements of the fish. As the herring swimbladder functions as a hydrostatic organ the low skeletal body content and high fat content results in a low swimbladder volume, so reducing the change in density with depth, an advantage to a fish undergoing diurnal vertical migrations. It was calculated that herring of Passamaquoddy Bay, N.B. can descend to their median daytime depth of 10 metres in August and 35 metres in February for sinking factors of 1016 and 1018 respectively. Predation may be reduced by the ability of herring to complete air uptake rapidly, to move upward without restriction by expelling any excess gas through the posterior duct and to liberate gas in times of stress in response to adrenaline so increasing body density and permitting rapid downward movement. Thus in many ways the herring because of its anatomical modifications has been able to adapt the physostome condition successfully to its marine environment. / Science, Faculty of / Zoology, Department of / Graduate
8

Molecular authentication of three traditional Chinese medicines: crocodile meat, fish air-bladder and radix stellariae.

January 2007 (has links)
Cheung, Chun Wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 111-128). / Abstracts in English and Chinese. / Acknowledgement --- p.ii / Abstract --- p.iv / 摘要 --- p.vii / Table of content --- p.ix / List of Figures --- p.xvii / List of Tables --- p.xix / Abbreviations --- p.xxi / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Complementary and Alternative Medicine (CAM) and Traditional Chinese Medicine (TCM) --- p.1 / Chapter 1.2 --- The development of Traditional Chinese Medicine --- p.2 / Chapter 1.3 --- Quality control of Traditional Chinese Medicine --- p.3 / Chapter 1.4 --- Problems of adulteration --- p.5 / Chapter 1.4.1 --- Confusion by common names --- p.5 / Chapter 1.4.2 --- Erroneous and intentional adulteration --- p.6 / Chapter 1.5 --- Authentication of Traditional Chinese Medicine using DNA techniques --- p.7 / Chapter 1.6 --- Crocodile meat --- p.10 / Chapter 1.6.1 --- Crocodile meat as Traditional Chinese Medicine --- p.10 / Chapter 1.6.2 --- Crocodile meat as exotic meat --- p.10 / Chapter 1.6.3 --- Effects of crocodile meat on mice --- p.12 / Chapter 1.6.4 --- Adulteration of crocodile meat in Hong Kong --- p.13 / Chapter 1.6.5 --- Authentication of crocodile meat --- p.14 / Chapter 1.6.5.1 --- SCAR analysis --- p.14 / Chapter 1.6.5.2 --- 12S and 16S ribosomal DNA --- p.14 / Chapter 1.7 --- Fish air-bladder --- p.15 / Chapter 1.7.1 --- Fish air-bladder as Traditional Chinese Medicine --- p.15 / Chapter 1.7.2 --- A case study --- p.16 / Chapter 1.7.3 --- Authentication of fish air-bladder --- p.17 / Chapter 1.8 --- Radix Stellariae --- p.18 / Chapter 1.8.1 --- Stellaria dichotoma L. var. lanceolata Bge --- p.18 / Chapter 1.8.2 --- Radix Stellariae as Traditional Chinese Medicine --- p.19 / Chapter 1.8.3 --- Chemicals in Radix Stellariae and their uses --- p.19 / Chapter 1.8.4 --- Adulteration of Radix Stellariae --- p.20 / Chapter 1.8.5 --- Authentication of Radix Stellariae --- p.21 / Chapter 1.8.5.1 --- Internal Transcribed Spacers (ITS) --- p.21 / Chapter 1.8.5.2 --- trnH-psbA intergenic spacer --- p.23 / Chapter 1.9 --- Objectives --- p.25 / Chapter Chapter 2. --- Materials and Methods --- p.26 / Chapter 2.1 --- Samples used in the study --- p.26 / Chapter 2.1.1 --- Crocodile and monitor lizard samples --- p.26 / Chapter 2.1.2 --- Sequence from NCBI database --- p.26 / Chapter 2.1.3 --- Fish air-bladder samples --- p.30 / Chapter 2.1.4 --- Radix Stellariae samples and samples of related species --- p.33 / Chapter 2.1.5 --- Sequences from NCBI database --- p.33 / Chapter 2.2 --- Reagents and equipments --- p.36 / Chapter 2.2.1 --- Sample preparation and DNA extraction --- p.36 / Chapter 2.2.2 --- Polymerase Chain Reaction --- p.38 / Chapter 2.2.3 --- Agarose gel electrophoresis and Gene Clean --- p.39 / Chapter 2.2.4 --- Cloning --- p.40 / Chapter 2.2.5 --- Cycle sequencing --- p.41 / Chapter 2.3 --- Experimental procedures --- p.42 / Chapter 2.3.1 --- Sample preparation --- p.42 / Chapter 2.3.2 --- DNA extraction --- p.42 / Chapter 2.3.3 --- Polymerase Chain Reaction --- p.44 / Chapter 2.3.4 --- Agarose gel electrophoresis --- p.47 / Chapter 2.3.5 --- Gene Clean --- p.47 / Chapter 2.3.6 --- Cloning --- p.48 / Chapter 2.3.7 --- Cycle sequencing and sequence analyses --- p.51 / Chapter Chapter 3. --- Crocodile meat - Results and Discussion --- p.54 / Chapter 3.1 --- Results --- p.54 / Chapter 3.1.1 --- SCAR analysis --- p.54 / Chapter 3.1.2 --- Sequence analyses --- p.55 / Chapter 3.1.3 --- The dendrograms --- p.56 / Chapter 3.2 --- Discussion --- p.60 / Chapter 3.2.1 --- SCAR as a quick and inexpensive method for the authentication of crocodile meat --- p.60 / Chapter 3.2.2 --- DNA sequencing - A useful tool to identify the source species of the crocodile meat --- p.61 / Chapter 3.2.3 --- Adulteration of crocodile meat in Hong Kong --- p.63 / Chapter 3.2.4 --- Source species of the genuine crocodile meats and the adulterants --- p.63 / Chapter 3.2.5 --- Regulation of labeling of food in Hong Kong --- p.69 / Chapter 3.2.6 --- Source species of the lizard head and tail from AFCD --- p.69 / Chapter 3.3 --- Summary --- p.70 / Chapter Chapter 4. --- Fish air-bladders - Results and Discussion --- p.72 / Chapter 4.1 --- Results --- p.72 / Chapter 4.1.1 --- Identities of sample BH and F1 --- p.73 / Chapter 4.1.2 --- Identity of sample BS --- p.74 / Chapter 4.1.3 --- Identities of samples GD and ZG --- p.74 / Chapter 4.1.4 --- Identity of sample GG --- p.74 / Chapter 4.1.5 --- "Identities of samples HB, HT and SH" --- p.75 / Chapter 4.1.6 --- Identity of sample JL --- p.75 / Chapter 4.1.7 --- Identity of sample MS --- p.76 / Chapter 4.1.8 --- Identity of sample RE --- p.76 / Chapter 4.2 --- Discussion --- p.77 / Chapter 4.2.1 --- Sample RE was confirmed to have originated from rabbit ears --- p.77 / Chapter 4.2.2 --- Identities of the dry fish air-bladders sold in Hong Kong --- p.79 / Chapter 4.2.3 --- Identities of the fresh fish air-bladders sold in Hong Kong --- p.82 / Chapter 4.2.4 --- Limitations of the use of DNA sequences for source species identification --- p.83 / Chapter 4.2.5 --- Variation in prices of fish air-bladders --- p.87 / Chapter 4.3 --- Summary --- p.88 / Chapter Chapter 5. --- Radix Stellariae - Results and Discussion --- p.89 / Chapter 5.1 --- Results --- p.89 / Chapter 5.1.1 --- Sequence analyses --- p.90 / Chapter 5.1.2 --- The dendrograms --- p.90 / Chapter 5.2 --- Discussion --- p.97 / Chapter 5.2.1 --- Identities of the samples obtained from the market --- p.97 / Chapter 5.2.2 --- Identity of sample Sdl4 --- p.97 / Chapter 5.2.3 --- Identities of samples Sd02R and Sd04 --- p.100 / Chapter 5.2.4 --- Myosoton aquaticum in the Stellaria-Myosoton clade --- p.104 / Chapter 5.2.5 --- Medicinal uses of the substitutes of Radix Stellariae --- p.105 / Chapter 5.3 --- Summary --- p.106 / Chapter Chapter 6. --- Conclusion --- p.107 / Reference --- p.111 / Appendix 1. 12S rDNA sequences of crocodilian and Varanus species obtained from NCBI database for sequence analyses --- p.129 / Appendix 2. 16S rDNA sequences of crocodilian and Varanus species obtained from NCBI database for sequence analyses --- p.130 / "Appendix 3. ITS sequences of the species in the genera Arenaria, Myosoton, Silene, and Stellaria obtained from NCBI database for sequence analyses" --- p.131 / Appendix 4. 7rnH-psbA intergenic spacer sequences of Silene species obtained from NCBI database for sequence analyses --- p.132 / Appendix 5. Sequence alignment of 12S rRNA gene sequences of crocodile and monitor lizard samples --- p.133 / Appendix 6. Sequence alignment of 16S rRNA gene sequences of crocodile and lizard samples --- p.141 / Appendix 7. Sequence alignment of coxl sequences of fish air-bladder samples --- p.149 / Appendix 8. Sequence alignment of 12S rRNA gene sequences of fish air-bladder samples --- p.151 / Appendix 9. Sequence alignment of 16S rRNA gene sequences of fish air-bladder samples --- p.153 / Appendix 10. Sequence alignment of coxl region of Vibrio parahaemolyticus and the coxl primers --- p.155 / Appendix 11. Sequence alignment of ITS sequences of Radix Stellariae and related samples --- p.156 / Appendix 12. Sequence alignment of trnH-psbA of Radix Stellariae and related samples --- p.163 / Appendix 13. Search results of coxl sequences of the fish air-bladder samples in BOLD-IDS --- p.167 / Appendix 14. Search results of coxl sequences of the fish air-bladder samples in NCBI nucleotide BLAST --- p.168 / Appendix 15. Search results of 12S rDNA sequences of the fish air-bladder samples in NCBI nucleotide BLAST --- p.169 / Appendix 16. Search results of 16S rDNA sequences of the fish air-bladder samples in NCBI nucleotide BLAST --- p.170 / Appendix 17. Sequence similarities (%) of coxl sequences of the fish air-bladder samples --- p.171 / Appendix 18. Sequence similarities (%) of 12S rDNA sequences of the fish air-bladder samples --- p.172 / Appendix 19. Sequence similarities (%) of 16S rDNA sequences of the fish air-bladder samples --- p.173
9

Acoustic investigations on bearded goby and jellyfish in the northern Benguela ecosystem

Uumati, Martha January 2013 (has links)
Historically the nutrient rich Benguela ecosystem supported large stocks of commercially important fish which sustained the Namibian fishing sector. Recently, non-exploited species i.e. bearded goby (Sufflogobius bibarbatus) and jellyfish (Chrysaora fulgida and Aequorea forskalea) have become more apparent and are described as key-species in this ecosystem. Empirical evidence for understanding the stock abundance and dynamics of S. bibarbatus and jellyfish are still sparse, as research focus has been mainly on commercially important fish. The abundance of these non-exploited species in relation to the environment and commercial species are also not well understood. Lack of methods to effectively assess jellyfish and S. bibarbatus have furthermore limited our knowledge. Acoustics can cover large water volumes and observe many trophic groups and interactions simultaneously hence currently proposed as the most reliable observation tool available to remotely study multiple species that are overlapping and widely distributed in marine ecosystems. For acoustic assessments using echo sounders, the ability to detect, identify and distinguish targets from each other and the echo ability (target strength: TS) of individual targets is pivotal to convert acoustic data from a calibrated system into significant biological measures. The lack of effective acoustic identification (ID) techniques and knowledge about TS of species may limit the application of acoustics. The swimbladder generally contributes more than 90% to the backscattered energy from fish, which makes knowledge of the swimbladder vital for understanding the acoustic properties of a fish. Prior to this study, the presence or absence of a swimbladder within S. bibarbatus has been uncertain. This thesis is an exploratory study addressing 1) the acoustic identification challenge of species in aggregating in mixed assemblages and 2) the acoustic characteristics of the target species. The latter two are of essence to assess the biomass, distributions and ecological interactions of these non-exploited. The multiple frequency data (18, 38, 70, 120 and 200 kHz) and trawl data used in this study were collected on a survey conducted by the RV G.O.Sars during April 2008 in the northern Benguela. Fifteen validated assumed to be ‘single species' trawl and acoustic datasets were selected and used in the application and developing of ID techniques. Traditional acoustic identification techniques (Sᵥ-differencing and relative frequency response r(f)) were adopted and found ineffective as standalones to discriminate the species under study. The overlaps in the Sᵥ differences of the three species complicated separation. A multivariate statistical approach, Linear Discriminant Analysis (LDA) was applied to predict which of the variables s[subscript(A)], S[subscript(A)], Δs[subscript(A)] and r(f) discriminated the three species groups from each other with a higher accuracy. It was found that by combining backscattering strength S[subscript(A)] and r(f) a correct classification accuracy of up to 95% could be obtained. Limitation is that the LDA technique as any classification method is not applicable in “real time” during surveys. A new technique, here within referred to as the Separator Technique, which incorporates the standard techniques, LDA results, a novel r(f) similarity comparison technique and a threshold s[subscript(A)] response technique was established. The effectiveness of the Separator Technique is in the recognition of similarities and stability in frequency response by simple correlation of the observed frequency response at systematic Sᵥ-threshold levels. Accurate acoustic classification depends on good and valid training datasets and there has so far not been a simple way of acoustically detecting if the selected assumed “pure” datasets is contaminated or not. Only available reliable source are the trawl samples. The r(f) similarity comparison method showed that some of the assumed ‘single species' trawls were mixed and that presence of <1% of strong scatterers could mask a weaker scatterer. By evaluating the threshold s[subscript(A)] frequency response, the proportion of thresholded backscattering could be quantified. A frequency which is more appropriate for the acoustic assessment of the respective species in mixed aggregations could also be identified. Further improvements of the Separator Technique are required in terms of the precise Sᵥ-cut levels. The presence of S. bibarbatus' swimbladder was confirmed from two thawed specimens. From further investigations on 26 dissections of sampled S. bibarbatus, the swimbladder was identified as a physoclist (closed swimbladder) with an extensive gas gland, and its morphology was roughly described as prolate spheroid shaped and with about 5ᴼ negatively tilted compared fish vertebra. This means that the strongest echo from a goby will be found when the fish is at about 5ᴼ head down relative to the horizontal. The in situ TS of 8 cm sized S. bibarbatus and the two jellyfish species: C. fulgida [umbrella diameter: 21.7 cm] and A. forskalea [16 cm] at multiple frequencies (18, 38, 70, 120 and 200 kHz) was estimated. At 38 kHz, the TS was -53 dB for S. bibarbatus, -58 dB for A. forskalea and -66 dB for C. fulgida. The single echo detection (SED) approach which is assumed to be a more accurate method for estimating TS than the previously applied methods for jellyfish. The TS results for S. bibarbatus are of similar magnitude to other published TS values of C. fulgida. This suggests that estimates of jellyfish may be overestimated due to inaccuracies in target identification. This thesis established the acoustic characteristics of jellyfish and S. bibarbatus within the northern Benguela which makes it possible to acoustically assess and monitor jellyfish and/or fish. The identification technique though still in early phases of development, can be applied to enhance quality of training datasets (samples) used in classification. This piece of work can reduce variability in biomass estimates that arises from masking or misclassification of echoes.

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