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551.
Background
Two economic factors make watermelon worthy of consideration as a feedstock for ethanol biofuel production. First, about 20% of each annual watermelon crop is left in the field because of surface blemishes or because they are misshapen; currently these are lost to growers as a source of revenue. Second, the neutraceutical value of lycopene and L-citrulline obtained from watermelon is at a threshold whereby watermelon could serve as starting material to extract and manufacture these products. Processing of watermelons to produce lycopene and L-citrulline, yields a waste stream of watermelon juice at the rate of over 500 L/t of watermelons. Since watermelon juice contains 7 to 10% (w/v) directly fermentable sugars and 15 to 35 μmol/ml of free amino acids, its potential as feedstock, diluent, and nitrogen supplement was investigated in fermentations to produce bioethanol. 相似文献552.
Uricase. Subunit composition and resistance to denaturants 总被引:3,自引:0,他引:3
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554.
J F Collawn H Donato J K Upshur W W Fish 《Comparative biochemistry and physiology. B, Comparative biochemistry》1985,81(4):901-904
Ferritin was isolated from human liver and spleen. Reversed phase high performance liquid chromatography of the ferritin subunits from each tissue yielded the same three chromatographic fractions. Physical and chemical characterization of the three fractions indicated that they represented at least two, perhaps three, chemically distinct subunits. 相似文献
555.
556.
A Baculovirus was found in larvae of the pitcher plant mosquito Wyeomyia smithii. This virus is similar in size and appearance to Baculoviruses from other mosquitoes. A unique feature of the virus is the formation of polymorphic inclusions. The prepatent period for this virus in W. smithii is 3–5 days. 相似文献
557.
Fledgling Bachman’s Sparrows in a longleaf pine ecosystem: survival,movements, and habitat selection
Alexander C. Fish Christopher S. DePerno Jessica M. Schillaci Christopher E. Moorman 《Journal of Field Ornithology》2020,91(4):354-366
Fledgling ecology remains understudied for many passerine species, yet information about the fledgling life stage is critical for understanding full-annual life cycles and population recruitment. We examined the survival, habitat selection, and movements of fledgling Bachman’s Sparrows (Peucaea aestivalis) in a longleaf pine-wiregrass (Pinus palustris-Aristida stricta) community managed with frequent prescribed fire. We captured and marked 36 fledglings on the day of fledging and used radio-telemetry to relocate them daily until independence during three breeding seasons (2014–2016). We visually confirmed the status of fledglings as live or dead during daily relocations and determined causes of mortality. We measured vegetation characteristics at fledgling locations and compared them to the characteristics of vegetation at the locations of adult males. We used a Known Fates analysis in Program MARK to estimate fledgling survival, and generalized linear mixed effect models to determine habitat selection. Estimated fledgling survival until independence was 0.31 (SE = 0.08), with most mortality during the first 4 d post-fledging. Fledglings with longer wing chords had higher rates of survival than those with shorter wing chords, possibly due to an increased ability to evade predators. Fledgling movements were restricted primarily to natal territories. Fledgling Bachman’s Sparrows were located in areas with greater woody plant, forb, and grass cover and less bare ground than available in natal territories. Similar to fledglings of other songbirds, understory woody and herbaceous plants appear to provide critical cover for fledgling Bachman’s Sparrows, and maintenance of such cover should receive consideration in management plans for longleaf pine communities. 相似文献
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559.
A thermotolerant species of Phormidium produced extracellular anti-microbial material during batch culture. Although this material was inactive when screened against a number of other cyanobacteria, it inhibited the growth of a wide range of Gram-positive and Gram-negative heterotrophic bacteria, Candida albicans and Cladosporium resinae.The authors are with the Department of Biological Sciences, University of Dundee, Dundee DD1 4HN, UK 相似文献
560.
Clades with taxa that have multiple locomotor adaptations represent a direct way to test the relationship between adaptation
and integration. If integration is influenced by functional requirements, integration should be most apparent where selection
is strongest and less evident where selection has been relaxed. If integration is primarily regulated by genetic constraints,
integration should be present irrespective of selection pressures. Here we use patterns of integration in the strepsirrhine
fore- and hind limbs as a test case. Strepsirrhine locomotion is relatively well-studied, and there are multiple clades that
share different locomotor modes. We found that quadrupeds have greater limb integration than vertical leapers. These results
suggest that variation can be expressed if selection for integration is relaxed. However, an unexpected pattern was revealed,
in which there appears to be some broader regulatory mechanism controlling overall limb integration. Our tests identified
a strong correlation between integration of the forelimb and integration of the hind limb. This broader mechanism may be evidence
of the primitive genetic control of limb integration. 相似文献