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Salmon: A Scientific MemoirIsabella, Jude 28 August 2013 (has links)
The reason for this story was to investigate a narrative that is important to the identity of North America’s Pacific Northwest Coast – a narrative that revolves around wild salmon, a narrative that always seemed too simple to me, a narrative that gives salmon a mythical status, and yet what does the average person know about this fish other than it floods grocery stores in fall and tastes good. How do we know this fish that supposedly defines the natural world of this place?
I began my research as a science writer, inspired by John Steinbeck’s The Log from the Sea of Cortez, in which he writes that the best way to achieve reality is by combining narrative with scientific data. So I went looking for a different story from the one most people read about in popular media, a story that’s overwhelmingly about conflict: I searched for a narrative that combines the science of what we know about salmon and a story of the scientists who study the fish, either directly or indirectly. I tried to follow Steinbeck’s example and include the narrative journeys we take in understanding the world around us, the journeys that rarely make it into scientific journals.
I went on about eight field trips with biology, ecology, and archaeology lab teams from the University of British Columbia and Simon Fraser University in Vancouver, with the Department of Fisheries and Oceans onboard the Canadian Coast Guard Ship the W.E. Ricker, and an archaeological crew from the Laich-Kwil-Tach Treaty Society in Campbell River, B.C.
At the same time, I was reading a number of things, including a 1938 dissertation by anthropologist Homer Barnett from the University of Oregon titled The Nature and Function of the Potlatch, a 2011 book by economist Ronald Trosper at the University of Arizona, Resilience, Reciprocity and Ecological Economics, and works by psychologist Douglas Medin at Northwestern University and anthropologist Scott Atran at the University of Michigan, written over the past two decades, particular paying attention to their writings on taxonomy and folkbiology.
My conclusions surprised me, a little. / Graduate / 0329 / 0324 / 0391
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Invasion dynamics of a non-indigenous bivalve, Nuttallia obscurata, (Reeve 1857), in the Northeast PacificDudas, Sarah 31 December 2005 (has links)
This thesis describes how life history characteristics of the varnish clam (Nuttallia
obscurata), and interactions with the physical environment and other species, have
contributed to its successful invasion in coastal British Columbia. Lab and field
experiments were conducted to investigate varnish clam larval ecology (i.e. larval rearing
experiments), adult population dynamics (i.e. annual population surveys, mark-recapture
and length-frequency analysis, growth modeling) and ecological interactions with native
species (i.e. predator/prey preference feeding trials). Using these results, a matrix
demographic model was developed to determine which life history stage contributes the
most to varnish clam population growth.
Larval rearing experiments indicated that temperature and salinity tolerances of varnish
clam larvae are comparable to native species, however the planktonic phase is slightly
longer (3-8 weeks). Based on local oceanographic circulation, varnish clam larvae have
the potential to disperse throughout their entire geographic range in just one reproductive
season. Varnish clam population surveys revealed spatiotemporal variation in density and
size. No relationships were evident between varnish clam density and the number or
density of co-occurring bivalve species. Length-frequency analysis suggested that
recruitment varies among sites, with high post-settlement mortality coinciding with high
recruitment. The presence of similar recruitment pulses at geographically separate sites
indicates regional scale processes may influence recruitment. Individual growth rates
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varied among sites, with higher growth corresponding to lower population densities and
water temperature. Monthly survival rates ranged from 0.81 – 0.99 and were lower for
clams 10-30 mm. Predator/prey preference feeding trials showed that crabs prefer
varnish clams to local species when clam burial depth is limited. Crabs therefore have
the potential to influence varnish clam distributions, particularly on beaches where the
varnish clam is unable to bury deeply. Based on matrix demographic analysis, adult
survival (e.g. clams ≥ 40 mm) is the most crucial factor for varnish clam population
growth, and drives the observed population growth differences between sites. This study
of the varnish clam invasion demonstrates that its success lies in both species (e.g.
lengthy planktonic phase, high survival) and regional (e.g. favourable ocean circulation
patterns for rapid dispersal) characteristics. Measures to reduce introductions should be
targeted in areas where introductions are likely to have the furthest reaching impacts.
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Bioanalytical Applications of Intramolecular H-Complexes of Near Infrared Bis(Heptamethine Cyanine) DyesKim, Junseok 15 July 2008 (has links)
This dissertation describes the advantages and feasibility of newly synthesized near-infrared (NIR) bis-heptamethine cyanine (BHmC) dyes for non-covalent labeling schemes. The NIR BHmCs were synthesized for biomolecule assay. The advantages of NIR BHmCs for biomolecule labeling and the instrumental advantages of the near-infrared region are also demonstrated. Chapter 1 introduces the theory and applications of dye chemistry. For bioanalysis, this chapter presents covalent and non-covalent labeling. The covalent labeling depends on the functionality of amino acids and the non-covalent labeling relies on the binding site of a protein. Due to the complicated binding process in non-covalent labeling, this chapter also discusses the binding equilibria in spectroscopic and chromatographic analyses. Chapter 2 and 3 evaluate the novel BHmCs for non-covalent labeling with human serum albumin (HSA) and report the influence of micro-environment on BHmCs. The interesting character of BHmCs in aqueous solutions is that the dyes exhibit non- or low-fluorescence compared to their monomer counterpart, RK780. It is due to their H-type closed clam-shell form in the solutions. The addition of HSA or organic solvents opens up the clam-shell form and enhances fluorescence. The binding equilibria are also examed. Chapter 4 provides a brief introduction that summaries the use of capillary electrophoresis (CE), and offers a detailed instrumentation that discusses the importance and advantage of a detector in NIR region for CE separation. Chapter 5 focuses on the use of NIR cyanine dyes with capillary electrcophoresis with near-infrared laser induce fluorescence (CE-NIR-LIF) detection. The NIR dyes with different functional groups show that RK780 is a suitable NIR dye for HSA labeling. The use of BHmCs with CE-NIR-LIF reduces signal noises that are commonly caused by the interaction between NIR cyanine dyes and negatively charged capillary wall. In addition, bovine carbonic anhydrase II (BCA II) is applied to study the influence of hydrophobicity on non-covalent labeling. Finally, chapter 6 presents the conformational dependency of BHmCs on the mobility in capillary and evaluates the further possibility of BHmCs for small molecule detection. Acridine orange (AO) is used as a sample and it breaks up the aggregate and enhances fluorescence. The inserted AO into BHmC changes the mobility in capillary, owing to the conformational changes by AO.
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Corbicula fluminea Invasion as a Secondary Effect of Hydrilla verticillata Management via Triploid Grass Carp (Ctenopharyngodon idella)Holbrook, David Lee 12 1900 (has links)
A study of Asian clam (Corbicula fluminea Müller) colonization in relation to changes in aquatic vegetation community as a result of management of Hydrilla verticillata (L. f.) Royle with grass carp was conducted at the Lewisville Aquatic Ecosystem Research Facility (LAERF), Lewisville, TX, from April 2015 through October 2016. Percent vegetation cover, C. fluminea abundance and water quality metrics (pH, turbidity, conductivity, DO, calcium, chlorophyll a) from 16 experimental subjects were analyzed. Treatments included four replicated grass carp stocking densities; 1-control with no fish stocked (n = 4), 2-low density of 40-43 fish per vegetated ha (n = 4), 3-medium density of 72-81 fish per vegetated ha (n = 4) and 4-high density of 110-129 fish per vegetated ha (n = 4). Data analysis showed statistical significance in the relation of C. fluminea abundance to percent vegetation cover (multiple linear regression, r2 = 0.820), grass carp stocking densities (two-way analysis of variance, p = <0.001) and chlorophyll a (multiple linear regression, r2 = 0.339). Findings of this research indicate the possibility that management of hydrilla had enabled establishment of secondary invasive species.
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Heavy metal fractionation studies in tidal sediment cores in the clam farms from Tan Thanh commune, Go Cong dong district, Tien Giang province, VietnamNguyen, Mai Lan 27 February 2019 (has links)
This paper introduces the results from a study on the distribution of heavy metals in chemical fractions in tidal sediment cores at four sample stations inside the baby clam breeding plain, inside the harvested clam breeding plain, and on the frontier between the plains in the clam farms in Tan Thanh commune, Go Cong Dong district, Tien Giang province, Vietnam. The partitioning of metals among the compartments of the sediment’s solid phase was investigated indirectly by selective sequential extraction of substances that are water-soluble, exchangeable, bound to carbonates, bound to Mn oxides, bound to amorphous Fe oxides, bound to crystalline Fe oxides, associated with organics and residual. In case of investigated heavy metals (HM), the concentrations of Zn and Hg exceeded the National Technical Regulation on Sediment Quality QCVN 43:2012/BTNMT by 1.12 - 3.53 times and 26.58 - 171.96 times, respectively. The highest HMs concentration was found in the oxidable fraction (more than 60%). The data demonstrates the important role of organic matters in the oxidable condition at the surficial sediment layer. Besides the oxidable fraction, high HMs concentrations were measured also in the residual fraction. The HMs content present in the solid residue also indicates the level of contamination in the river system: the greater the percentage of HMs present in the solid residue, the lesser the pollution in the environment because this solid residue involves components that can not be remobilized. The HMs concentrations depending on the depth of the sediment indicate that clam’s digestive activity or the decomposition of tissue and shell of clams possibly affects the content of HMs. / Bài báo giới thiệu các kết quả nghiên cứu về sự phân bố kim loại nặng dưới các dạng liên kết khác nhau trong các mẫu lõi trầm tích tại các bãi nuôi nghêu giống, bãi nuôi nghêu sau khi đã thu hoạch, và ranh giới giữa các bãi nuôi nghêu tại xã Tân Thành, huyện Gò Công Đông, tỉnh Tiền Giang, Việt Nam. Các dạng pha liên kết bao gồm: 1.pha hòa tan; 2. pha trao đổi; 3.liên kết với các bô nát; 4. liên kết với Man gan ô xít; 5. liên kết với sắt ô xít vô định hình; 6. liên kết với sắt ô xít dạng tinh thể; 7. liên kết với thành phần hữu cơ và; 8. Phần bã rắn. Trong các kim loại nặng (KLN) được phân tích, hàm lượng Zn và Hg vượt quá tiêu chuẩn cho phép QCVN 43:2012/BTNMT lần lượt từ 1,12 – 3,53 và 24,58 – 171,96 lần. Hàm lượng KLN tồn tại nhiều nhất dưới dạng liên kết với các thành phần có khả năng ô xi hóa với tỉ lệ hơn 60% chỉ ra vai trò của thành phần hữu cơ trong điều kiện ô xi hóa tại lớp trầm tích tầng mặt. Sau các thành phần có khả năng ôxi hóa, các KLN hiện diện trong phần bã rắn nhiều hơn trong các pha khác. Sự có mặt của KLN trong phần bã rắn chỉ ra mức độ ô nhiễm của hệ thống sông: càng nhiều phần trăm KLN có mặt trong phần bã rắn, càng ít ô nhiễm trong môi trường bởi phần bã rắn này liên quan đến các thành phần không thể bị rửa tách. Sự phụ thuộc theo độ sâu của hàm lượng kim loại nặng đưa ra khả năng về sự ảnh hưởng của hoạt động tiêu hóa và quá trình phân hủy của nghêu lên hàm lượng kim loại nặng.
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Politické programy české reprezentace ve druhé polovině 19. století / Political programmes of the Czech representation in the second half of the 19th centuryZikmund, Michal January 2016 (has links)
The thesis Political Programmes of the Czech Representation in the Second Halve of the 19th Century focuses on both programme documents and actual work of Czech political parties, whether more or less institutionalized, between the years 1848 (March Revolution) and 1918 (the downfall of Austria-Hungary). At first it summarizes the historical development in the respective period (Chapter 1), next, it analyses programmes of political parties in three broadly defined topics: 1) Organisation of the empire, question of the Czech State Right (Chapter 2); 2) Constitutionalism, civil rights and role of a citizen (Chapter 3) and 3) National matters (Chapter 4). The attitudes about each of these areas of the following political parties are defined: Bohemian nobility, National Party (till 1874) or Old Czechs (since then), Young Czechs, Social Democrats, Agrarians, Catholic parties, National Socialists, Progress parties and parties of the Radical State Right, Realists and Anarchists. For the conclusion, the author of the thesis attempts to characterise and evaluating the Czech political representation, as well as its importance for the development since 1918.
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