Effects of astaxanthin on Brachionus manjavacas (Rotifera) population growth          下载免费PDF全文

Rachel K Johnston  Emma J Siegfried  Terry W Snell  John Carberry  Matthew Carberry  Cody Brown  Shereen Farooq 《Aquaculture Research》2018,49(6):2278-2287

Astaxanthin is a red secondary carotenoid and powerful antioxidant that is used in aquaculture to enhance colour and improve fish health. Brachionid rotifers are often used as a live feed for larval fish, but do not contain endogenous carotenoids. However, they can be enriched with astaxanthin through their diet and transfer it to larval predators. When supplemented with 2 μg/ml astaxanthin oleoresin extracted from the green alga Haematococcus pluvialis, Brachionus manjavacas rotifer cultures reached significantly higher population densities and maintained them for longer. Furthermore, data are presented that exposure to oleoresin or pure astaxanthin enhances rotifer resistance to oxidative stress, a common cause for the collapse of rotifer mass cultures. Astaxanthin can be visualized in the gut of the rotifers, allowing the time course of uptake to be estimated by image analysis. Using this method, it was found that accumulation of astaxanthin in the rotifer gut saturates after 1.5 hr of exposure. The bioactive dose of astaxanthin oleoresin for rotifers was found to be 1–20 μg/ml. Astaxanthin concentration in rotifer tissues was measured using absorbance spectrophotometry. It was found that treating rotifers with 20 μg/ml for 24 hr; the concentration of astaxanthin absorbed into rotifer tissues was 2.6 mg/g. Overall, these experiments indicate that astaxanthin extracted from H. pluvialis can be used to improve the productivity and stability of rotifer mass cultures by increasing oxidative stress resistance and enhance the nutritional content of rotifers for larval fish.  相似文献   

周末去天津散步     

Emma 《百姓》2009,(8):54-56

天津对于北京人来说,是个伸腿儿就能到,但却与北京有着不同气质的另一城.周末去天津,看看老房子,听听老段子,轻松一日游,花不了几个钱,又别有一番味道.  相似文献   

Observing fish interactions with marine energy turbines using acoustic cameras     

Emma Cotter  Garrett Staines 《Fish and Fisheries》2023,24(6):1020-1033

Marine current energy converters such as tidal and riverine turbines have the potential to provide reliable, clean power. The risk of collision of fishes with marine energy turbines is not yet well understood, in part due to the challenges associated with observing fish at turbine sites. Turbidity and light availability can limit the effectiveness of optical sensors like video cameras, motivating the use of acoustic cameras for this task. However, challenges persist in collecting and interpreting data acquired from acoustic cameras. Given the limited number of turbine deployments to date, it is prudent to draw on the application of acoustic cameras to monitor fish in other scenarios. This article synthesizes their use for other fisheries applications to inform best practices and set realistic expectations for the results of acoustic camera monitoring at turbine sites. We discuss six key tasks performed with acoustic cameras: detecting objects, identifying objects as fish, counting fish, measuring fish, classifying fish taxonomically and analysing fish behavior. Specific challenges to monitoring fish at turbine sites are discussed. This article is intended to serve as a reference for researchers, regulators and marine energy developers on effective use of acoustic cameras to monitor fish at turbine sites. The studies detailed in this article provide evidence that, in some scenarios, acoustic cameras can be used to inform the risk of fish collision with marine energy turbines but doing so requires careful study design and data processing.  相似文献   

Adaptation strategies of the Icelandic horse with induced forelimb lameness at walk,trot and tölt     

Ineke H. Smit  Elin Hernlund  Emma Persson-Sjodin  Sigridur Björnsdóttir  Helga Gunnarsdottir  Vikingur Gunnarsson  Marie Rhodin  Filipe M. Serra Braganca 《Equine veterinary journal》2024,56(3):617-630

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Immunochemical and Electrophoretic Analysis of the Modification of Wheat Proteins in Extruded Flour Products     

Michael A. K. Partridge  Yan Jiang  John H. Skerritt  Karen M. Schaich 《Cereal Chemistry》2003,80(6):791-798

Antibodies specific for wheat proteins were used to identify protein fractions modified during extrusion of Hard Red Spring wheat flour (14% protein) under four different combinations of extrusion conditions (18 and 24% feed moisture and 145 and 175°C die temperature). Antibody binding was assessed on immunoblots of proteins extracted from flour and extrudates separated by SDS‐PAGE. Antibodies to high molecular weight glutenin subunits (HMW‐GS) and to B‐group low molecular weight glutenin subunits (LMW‐GS) recognized intact subunits from both flour and extrudates. Antibodies to C‐group LMW‐GS had diminished binding to extruded proteins. Glutenin‐specific antibodies also recognized protein in the extrudates migrating as a smear at molecular weights higher than intact subunits, indicating cross‐linked proteins. Antibodies recognized albumins or globulins in flour but not in extrudates, evidence that these fractions undergo significant modification during extrusion. Acid‐PAGE and antibody reaction of gliadins extracted in 1M urea and in 70% ethanol revealed total loss of cysteine‐containing α, β, γ‐gliadins but no obvious effects on sulfur‐poor ω‐gliadins, suggesting gliadin modification involves replacing intramolecular disulfides with intermolecular disulfide cross‐links. Identifying protein fractions modified during different extrusion conditions may provide new options for tailoring extrusion to achieve specific textural characteristics.  相似文献   

Characterizing seabird bycatch in the eastern Australian tuna and billfish pelagic longline fishery in relation to temporal,spatial and biological influences     

Rowan Trebilco  Rosemary Gales  Emma Lawrence  Rachael Alderman  Graham Robertson  G. Barry Baker 《水产资源保护:海洋与淡水生态系统》2010,20(5):531-542

• 1. Seabirds killed incidentally in Australia's eastern tuna and billfish (ETBF) longline fishery between September 2001 and June 2006 were examined to evaluate species composition and to relate, where possible, capture events to operational and environmental factors.
• 2. During this period 2.129 million hooks on 2202 shots were observed, and 369 birds were reported killed. The majority (78%) of these were flesh‐footed shearwaters (Puffinus carniepes), 53% of which were male and 44% female. Smaller numbers of medium to large sized albatrosses (Diomedeidae, predominantly female) and other shearwaters (Puffinus spp.) and petrels (Pterodroma spp.) dominated the remainder of the bycatch.
• 3. Of the 369 birds reported taken as bycatch, 280 were available for necropsy, and species identifications performed in situ by observers were assessed. While observer identifications were generally correct for common species, performance was poor for less common ones.
• 4. The geographical location (latitude) of shots, season, time of day at which shots were set, and bait type and life status (dead or alive) influenced the seabird bycatch rate. The majority of captures (87% overall) occurred between 30 and 35°S, with bycatch being lowest in winter, and remaining at similar levels across the other seasons.
• 5. The use of live fish bait was generally associated with increased captures of both seabirds overall, and flesh‐footed shearwaters in particular. Copyright © 2010 John Wiley & Sons, Ltd.

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Synergistic and Additive Effects of Three High Molecular Weight Glutenin Subunit Loci. II. Effects on Wheat Dough Functionality and End‐Use Quality     

H. L. Beasley  S. Uthayakumaran  F. L. Stoddard  S. J. Partridge  L. Daqiq  P. Chong  F. Bks 《Cereal Chemistry》2002,79(2):301-307

Understanding the relationship between basic and applied rheological parameters and the contribution of wheat flour protein content and composition in defining these parameters requires information on the roles of individual flour protein components. The high molecular weight glutenin subunit (HMW‐GS) proteins are major contributors to dough strength and stability. This study focused on eight homozygous wheat lines derived from the bread wheat cvs. Olympic and Gabo with systematic deletions at each of three HMW‐GS encoding gene loci, Glu‐A1, Glu‐B1, and Glu‐D1. Flour protein levels were adjusted to a constant 9% by adding starch. Functionality of the flours was characterized by small‐scale methods (2‐g mixograph, microextension tester). End‐use quality was evaluated by 2‐g microbaking and 10‐g noodle‐making procedures. In this sample set, the Glu‐D1 HMW‐GS (5+10) made a significantly larger contribution to dough properties than HMW‐GS coded by Glu‐B1 (17+18), while subunit 1 coded by Glu‐A1 made the smallest contribution to functionality. These differences remained after removing variations in glutenin‐to‐gliadin ratio. Correlations showed that both basic rheological characteristics and protein size distributions of these flours were good predictors of several applied rheological and end‐use quality tests.  相似文献   

Movement,depth distribution and survival of spinetail devilrays (Mobula japanica) tagged and released from purse‐seine catches in New Zealand          下载免费PDF全文

Malcolm P. Francis  Emma G. Jones 《水产资源保护:海洋与淡水生态系统》2017,27(1):219-236

Methionine as a safe and effective novel biorational mosquito larvicide     

Emma NI Weeks  Julie Baniszewski  Salvador A Gezan  Sandra A Allan  James P Cuda  Bruce R Stevens 《Pest management science》2019,75(2):346-355

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Development of Immediate Release Tablets Containing Calcium Lactate Synthetized from Black Sea Mussel Shells     

Magdalena Mititelu  Elena Moro&#x;an  Anca Cecilia Nicoar&#x;  Ana Andreea Sec&#x;reanu  Adina Magdalena Musuc  Irina Atkinson  Jeanina Pandele Cusu  George Mihai Niulescu  Emma Adriana Ozon  Iulian Sarbu  Teodora Dalila Balaci 《Marine drugs》2022,20(1)

Nowadays, the use of marine by-products as precursor materials has gained great interest in the extraction and production of chemical compounds with suitable properties and possible pharmaceutical applications. The present paper presents the development of a new immediate release tablet containing calcium lactate obtained from Black Sea mussel shells. Compared with other calcium salts, calcium lactate has good solubility and bioavailability. In the pharmaceutical preparations, calcium lactate was extensively utilized as a calcium source for preventing and treating calcium deficiencies. The physical and chemical characteristics of synthesized calcium lactate were evaluated using Fourier Transform Infrared Spectroscopy, X-ray diffraction analysis and thermal analysis. Further, the various pharmacotechnical properties of the calcium lactate obtained from mussel shells were determined in comparison with an industrial used direct compressible Calcium lactate DC (PURACAL^®). The obtained results suggest that mussel shell by-products are suitable for the development of chemical compounds with potential applications in the pharmaceutical domain.  相似文献