The effect of temperature on the energy budget of the Manila clam, <Emphasis Type="Italic">Ruditapes philippinarum</Emphasis>     

Kyung Nam Han  Soon Woo Lee  Soon Young Wang 《Aquaculture International》2008,16(2):143-152

In this study, the energy budget of the Manila clam, Ruditapes philippinarum, was evaluated after one-week acclimation periods at 5, 10, 15, 20, and 25°C. Small clams (151 ± 12 mg DW) and large clams (353 ± 16 mg DW) were fed with the microalgae, Isochrysis galbana. Filtration rate, ingestion rate, assimilation efficiency, oxygen-consumption rate, and ammonia excretion rate were measured. Both filtration rate and ingestion rate of small and large clams were found to be related to temperature. The highest Q ₁₀ values were measured in the range 15–20°C for both small and large clams. Assimilation efficiency of both small and large clams was not significantly influenced by temperature, although the maximum mean values were detected at 20°C. Oxygen consumption rate and ammonia excretion rate of small and large clams were found to be related directly to temperature over the entire range, with a maximum being detected at 25°C. The highest Q ₁₀ value was estimated in the range 10–15°C with regard to oxygen consumption rate, and in the range of 15–20°C with regard to ammonia excretion rate. Scope for growth (SFG) was positive at all temperatures, achieving a maximum value at 20°C in both small and large clams, primarily as a consequence of the enhanced ingestion rate which offset the concomitant elevation in the metabolic rate. In this study we have estimated the thermal optimum for this species at 20°C.  相似文献   

Exploring the efficacy of vaccine techniques in juvenile sablefish,Anoplopoma fimbria          下载免费PDF全文

Mary R. Arkoosh  Joseph P. Dietrich  Mary Beth Rew  Wendy Olson  Graham Young  Frederick W. Goetz 《Aquaculture Research》2018,49(1):205-216

Wild sablefish, Anoplopoma fimbria, are a valuable commercial species whose populations are declining. Fortunately, sablefish are excellent species for commercial aquaculture. Sablefish raised under high‐density conditions in the marine environment require the use of efficacious vaccines to control disease. Sablefish impacted by disease in net pens may have poor flesh quality and high mortality during grow‐out. As a result, disease can cause financial hardship for sablefish aquaculture operators. The efficacy of a multivalent vaccine preparation for sablefish, administered either by intraperitoneal (i.p.) injection or by immersion, against atypical and typical Aeromonas salmonicida, the causative agents of atypical and typical furunculosis, respectively, was examined. A. salmonicida can affect sablefish at any age and size. Consequently, an efficacious vaccine that can be appropriately and optimally administered to all life stages is desirable. Sablefish vaccinated by immersion at ~1.5 or ~4.5 g with a whole‐cell multivalent vaccine were not protected against either typical or atypical A. salmonicida. Factors that may have contributed to the ineffectiveness of the immersion vaccine are discussed. By contrast, the relative per cent survival (RPS) or potency of the whole‐cell multivalent vaccine injected i.p. in juvenile sablefish at ~50 g against typical and atypical A. salmonicida was 94.3% and 81.7% respectively. The high RPS values indicated that the vaccine successfully initiated an immune response in sablefish upon a second encounter with the pathogen.  相似文献   

Characterization of phytochemicals and antioxidant activities of a purple tomato (Solanum lycopersicum L.)     

Li H  Deng Z  Liu R  Young JC  Zhu H  Loewen S  Tsao R 《Journal of agricultural and food chemistry》2011,59(21):11803-11811

A newly developed nongenetically modified purple tomato V118 was investigated for its phytochemical compositions and antioxidant activities. A highly efficient and sensitive UPLC method was developed for both the phenolics and carotenoids, which showed that in addition to the phytochemicals commonly known for tomatoes, V118 had a unique composition of anthocyanins. The total carotenoid content of V118 was 234.78 μg/g dry weight (DW), and the total phenolic content was 659.11 mg GAE/100 g DW. The antioxidant activities of the lipophilic extract as measured by the PCL and ORAC-L assays were 30.11 μmol TE/g DW and 11.97 μmol TE/g DW, respectively, while the hydrophilic extracts as determined by the ORAC-H and FRAP assays were 323.23 μmol TE/g DW and 54.95 μmol AAE/g DW, respectively. The LC-MS study showed three major anthocyanins, which were mainly acylglycosides of petunidin and malvidin. This study showed that purple tomatoes such as V118 possess additional phytochemicals like anthocyanins, which can potentially have added health benefits.  相似文献   

Diesel and glyphosate price changes benefit the economics of conservation tillage versus traditional tillage     

Elizabeth L. Nail  Douglas L. Young  William F. Schillinger   《Soil & Tillage Research》2007,94(2):321-327

Recent increases in diesel price and decreases in glyphosate [N-(phosphonomethyl) glycine] price should favor the profitability and farmer acceptance of herbicide-intensive conservation tillage systems versus fuel-intensive traditional tillage (TT) systems. Profitability results from a long-term field experiment that compared TT, minimum tillage (MT), and delayed minimum tillage (DMT) systems for winter wheat–(Triticum aestivum L.)summer fallow in eastern Washington, USA were calculated using both 1998 and 2005 input prices. Net returns for the MT and DMT systems increased by US$ 6.37 and 6.30 (rotational ha)⁻¹, respectively, and net returns to the TT system decreased by US$ 2.36 (rotational ha)⁻¹ when 2005 versus 1998 prices were used. Here, rotational ha equals 0.5 ha fallow and 0.5 ha wheat. Focusing on the dominant crop of soft white winter wheat (SWWW), the 2005 price hikes pushed diesel costs up for all systems, from US$ 6.81 (rotational ha)⁻¹ for DMT to US$ 9.00 (rotational ha)⁻¹ for TT. The cost of diesel for the conservation tillage systems, relative to the cost for TT, decreased by US$ 1.50–2.20 (rotational ha)⁻¹. The conservation tillage systems accrue greater savings from the price reduction in glyphosate because they consume more of this herbicide. An unanticipated result was that relative cost savings from price changes in N fertilizer rivaled those from diesel and glyphosate because anhydrous NH₃–N was exclusively used in the experiment for TT and aqueous NH₃–N for MT and DMT. The price of anhydrous NH₃–N increased from US$ 0.55 kg⁻¹ in 1998 to 0.85 kg⁻¹ in 2005, a 56% increase. Aqueous NH₃–N only increased from $0.75 kg⁻¹ in 1998 to 0.85 kg⁻¹ in 2005, a 15% increase. The greater price increase for anhydrous NH₃–N penalized the TT system because of its use of this fertilizer. If the same source of N fertilizer were used on all three tillage systems, this fertilizer cost effect would disappear. Nonetheless, the conservation tillage systems still retained a statistically significant profitability advantage over TT even if the same fertilizer was used throughout. The sharp price increase for diesel and the concurrent price decrease for glyphosate herbicide favored the conservation tillage systems over TT in this study. Results provide strong evidence for the superior profitability of conservation tillage winter wheat–summer fallow under current economic conditions.  相似文献   

Papaya seed represents a rich source of biologically active isothiocyanate   总被引：1，自引：0，他引：1  

Nakamura Y  Yoshimoto M  Murata Y  Shimoishi Y  Asai Y  Park EY  Sato K  Nakamura Y 《Journal of agricultural and food chemistry》2007,55(11):4407-4413

In the present study, papaya (Carica papaya) seed and edible pulp were carefully separated and then the contents of benzyl isothiocyanate and the corresponding glucosinolate (benzyl glucosinolate, glucotropaeolin) quantified in each part. The papaya seed with myrosinase inactivation contained >1 mmol of benzyl glucosinolate in 100 g of fresh seed. This content is equivalent to that of Karami daikon (the hottest Japanese white radish) or that of cress. The papaya seed extract also showed a very high activity of myrosinase and, without myrosinase inactivation, produced 460 micromol of benzyl isothiocyanate in 100 g of seed. In contrast, papaya pulp contained an undetectable amount of benzyl glucosinolate and showed no significant myrosinase activity. The n-hexane extract of the papaya seed homogenate was highly effective in inhibiting superoxide generation and apoptosis induction in HL-60 cells, the activities of which are comparable to those of authentic benzyl isothiocyanate.  相似文献   

The Use of Biofilters to Reduce Atmospheric Methane Emissions from Landfills: Part I. Biofilter Design     

Park  So Young  Brown  K. W.  Thomas  J. C. 《Water, air, and soil pollution》2004,155(1-4):63-85

Previous laboratory research has shown that biofilters have the potential to reduce CH₄ emissions from landfills by as much as 83%. However, to achieve this level of CH₄ reduction biofilters must be properly designed. The present study was conducted to develop a method for properly designing biofilters based on landfill size and location. A quadratic equation was developed to describe the dependence of CH₄ oxidation rate in a sandy loam textured soil as a function of soil temperature, soil moisture and ammonium nitrogen concentration. Using this equation and the average monthly soil temperature and moisture contents for the largest cities of each of the 48 contiguous states, the monthly CH₄ oxidation rate at each location was calculated. Then, assuming a standard landfill depth of 27.6 m, and a standard area of 121,500 m², the required biofilter size was calculated. Finally, the ratio of biofilter size to landfill size was calculated. Design calculations for biofilters located in the states of Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina and Texas where the CH₄ oxidation rates are relatively high throughout the year indicate that the necessary biofilter sizes are small. In addition, biofilters in these states may be expected to be effective throughout the year. In contrast, the calculations indicated biofilter systems in the states of Idaho, Minnesota and North Dakota will have much lower efficiencies during much of the year due to unfavorable soil moisture and temperature ranges. Given proper design, installation and management, a biofilter should be capable of achieving a significant reduction in atmospheric CH₄ emission as compared to emissions from the same landfill without a biofilter.  相似文献   

Variation and correlation analysis of flavonoids and carotenoids in Korean pigmented rice (Oryza sativa L.) cultivars     

Kim JK  Lee SY  Chu SM  Lim SH  Suh SC  Lee YT  Cho HS  Ha SH 《Journal of agricultural and food chemistry》2010,58(24):12804-12809

Flavonoids and carotenoids of pigmented rice ( Oryza sativa L.), including five black cultivars and two red cultivars, from Korea were characterized to determine the diversity among the phytochemicals and to analyze the relationships among their contents. Black cultivars were higher in flavonoids and carotenoids than the red and white cultivars. The profiles of eight phytochemicals identified from the rice grains were subjected to principal component analysis (PCA) to evaluate the differences among cultivars. PCA could fully distinguish between these cultivars. The Heugjinjubyeo (BR-1) and Heugseolbyeo (BR-2) cultivars were separated from the others based on flavonoid and carotenoid concentrations. Flavonoid contents had a positive correlation with carotenoid contents among all rice grains. The BR-1 and BR-2 cultivars appear to be good candidates for future breeding programs because they have simultaneously high flavonoid and carotenoid contents.  相似文献   

Interactions and self-organization in the soil-microbe complex   总被引：6，自引：0，他引：6  

Young IM  Crawford JW 《Science (New York, N.Y.)》2004,304(5677):1634-1637

Soil is the most complicated biomaterial on the planet. As with any material, the physical habitat is of prime importance in determining and regulating biological activity. However, until recently the opaque nature of soil has meant that any interrogation of its interior architecture has been relatively rudimentary, restricted to simple qualitative expressions of the physical heterogeneity that fail to relate to any specific function. However, new techniques and insights into the biophysical and biochemical processes of this inner space are leading to the developments of theoretical frameworks and experimental approaches that will allow us to sustainably manage Earth's most important resource. We introduce the concept that the soil-microbe system is self-organized and suggest new priorities for research based on an integrative approach that combines biochemistry and biophysics.  相似文献   

Fabrication of electropsun PLGA and small intestine submucosa-blended nanofibrous membranes and their biocompatibility for wound healing     

Kihoon Kim  Jong Yoon Lee  Hyun Kim  Jaiho Shin  Yongwon Shin  Young Tai Yoo  Hwi-Yool Kim 《Fibers and Polymers》2017,18(2):231-239

In recent decades, tremendous research has focused on the production of nanoscale fibers using synthetic polymers, with the goal of fabricating nanofibrous scaffolds for wound healing. However, the hydrophobicity of such polymers typically hinders attachment and proliferation of the cells. In this study, we combined poly-d,l-lactide-co-glycolide (PLGA) and small intestine submucosa (SIS) to fabricate blended nanofibers for wound healing by electrospinning. PLGA and SIS were dissolved in 1,1,1,3,3,3-hexafluoro isopropanol to produce different weight ratios of PLGA/SIS-blended nanofibrous membranes (NFM). Physicochemical characterization of the electrospun NFM was performed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, water contact angle analysis, degradation test and tensile testing. The PLGA/SIS-blended NFM showed improved hydrophilicity and tensile strength. Better infiltration, attachment and proliferation of rat granulation fibroblasts of PLGA/SIS-blended NFMs compared to PLGA NFMs were identified by morphological differences determined by SEM and a water-soluble tetrazolium salt assay kit. Based on our results, the PLGA/SIS blended NFMs were found to be suitable for use as a potential material for wound dressing.  相似文献   

Responses of surface SOC to long‐term experimental warming vary between different heath types in the high Arctic tundra     

Ji Young Jung  Anders Michelsen  Mincheol Kim  Sungjin Nam  Niels M. Schmidt  Sujeong Jeong  Yong‐Hoe Choe  Bang Yong Lee  Ho Il Yoon  Yoo Kyung Lee 《European Journal of Soil Science》2020,71(4):752-767

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