THE TEACHING OF ELEMENTARY DYNAMICS     

Cain W 《Science (New York, N.Y.)》1916,44(1123):23-24

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Woody and herbaceous competition effects on the growth of naturally regenerated loblolly and shortleaf pines through 11 years     

Cain  Michael D. 《New Forests》1997,14(2):107-125

Four levels of vegetative competition were used to quantify the growth of loblolly and shortleaf pines (Pinus taeda L. and P. echinata Mill.) in naturally regenerated, even-aged stands on the Upper Coastal Plain of southeastern Arkansas, USA. Treatments included: (1) no competition control, (2) woody competition control, (3) herbaceous competition control, and (4) total control of nonpine vegetation. After pines became established from natural seeding, herbicides were used to control herbaceous plants for 4 consecutive years and woody plants for 5 consecutive years. Even though 89% of crop pines on untreated check plots were free-to-grow 11 years after establishment, crop pines on vegetation control plots were larger (P<0.001) in mean dbh, total height, and volume per tree. From age 5 through 11 years, crop pine diameter growth increased on woody control plots and decreased on herbaceous control plots because of hardwood competition in the latter treatment. At age 11, crop pine volume production averaged 207 m³/ha on total control plots, 158 m³/ha on herbaceous control plots, 130 m³/ha on woody control plots, and 102 m³/ha on untreated check plots.  相似文献   

Genotypic relatedness and antimicrobial resistance of Staphylococcus schleiferi in clinical samples from dogs in different geographic regions of the United States          下载免费PDF全文

Darcie A. Kunder  Christine L. Cain  Kathleen O'Shea  Stephen D. Cole  Shelley C. Rankin 《Veterinary dermatology》2015,26(6):406-e94

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Crystallization behavior and texture of trans-containing and trans-free palm oil based confectionery fats     

De Graef V  Foubert I  Smith KW  Cain FW  Dewettinck K 《Journal of agricultural and food chemistry》2007,55(25):10258-10265

The objective of this study was to gain insight into the role of trans fatty acids in determining the crystallization behavior and texture of palm-based confectionery fats. Therefore, the isothermal crystallization behavior of two series, each of three fats, one trans-containing and one trans-free, was examined by pNMR, DSC, and rheology. Furthermore, the hardness of these samples was examined at three different storage times at 10 degrees C. All of the trans free samples showed a two-step crystallization at 10 degrees C which is hypothesized to be an alpha-mediated beta' crystallization for two of the samples and a fractionated crystallization in the beta' polymorph for the third, while the trans-containing fats crystallized in a single step, probably a direct beta' crystallization. The trans-containing fat series clearly crystallized faster than the trans-free fat series and also yielded higher hardness values at all storage times investigated. The presence of trans fatty acids seems to reduce the effect of compositional variations on the crystallization process. For the trans free fats, chemical composition was much more critical in determining the crystallization rate, the SFC, and the final hardness value.  相似文献   

Evaluation of a boat-mounted electro-trawl as a commercial harvesting system for crawfish     

C.Dean Cain  James W. Avault 《Aquacultural Engineering》1983,2(2):135-152

Field experiments were conducted to ascertain if trawling utilizing electrical currents was an effective method of harvesting crawfish.Results suggest that catch efficiency relative to vegetation density is more dependent upon trawl mechanical ability than on relative crawfish abundance. Catch is also dependent upon trawling speed, water depth and time of trawling. Trawling consistently yielded higher catches per area than did conventional traps. Unmarketable individuals and mortality were no different for the two gear types.Trawling could be an effective supplemental harvesting method, but additional work needs to be performed to alleviate electrical and mechanical problems before economic efficiency can be realistic.  相似文献   

Characterization of serum and mucosal antibody responses and relative per cent survival in rainbow trout, Oncorhynchus mykiss (Walbaum), following immunization and challenge with Flavobacterium psychrophilum   总被引：1，自引：0，他引：1  

B R LaFrentz  S E LaPatra  G R Jones  J L Congleton  B Sun  K D Cain 《Journal of fish diseases》2002,25(12):703-713

Serum and mucosal antibody responses of juvenile rainbow trout, Oncorhynchus mykiss, were characterized by enzyme‐linked immunosorbent assay (ELISA) following immunization with various preparations of formalin‐killed Flavobacterium psychrophilum cells. The protective nature of these preparations was then determined by immunizing rainbow trout fry and challenging with the bacterium. Juvenile rainbow trout immunized intraperitoneally (i.p.) with formalin‐killed F. psychrophilum emulsified with Freund's complete adjuvant (FCA), and i.p. with formalin‐killed F. psychrophilum either with or without culture supernatant generated significant serum antibody responses by 6 and 9 weeks, respectively. Significant mucosal antibody responses were detected by 9 weeks only in fish immunized i.p. with killed F. psychrophilum/FCA. Following immunization and bacterial challenge of rainbow trout fry, protective immunity was conferred in F. psychrophilum/FCA and saline/FCA groups with relative per cent survival values of up to 83 and 51, respectively. Significant protection was not observed in treatment groups immunized by immersion or i.p. without adjuvant at the challenge doses tested. Results suggest that stimulation of non‐specific immune factors enhances the ability of fish to mount a protective immune response, but specific antibody appears necessary to provide near complete protection. In this study, an ELISA was developed to monitor anti‐F. psychrophilum antibody production in trout. The relationship of such responses to protective immunity suggests that future vaccination strategies against coldwater disease may require stimulation of both the innate and adaptive arms of the immune response.  相似文献   

Elizabeth Finnis: Reimaging marginalized foods: global processes,local places     

Taylor Cain 《Agriculture and Human Values》2014,31(4):689-690

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Quantitative PCR demonstrates a positive correlation between a Rickettsia-like organism and severity of strawberry disease lesions in rainbow trout, Oncorhynchus mykiss (Walbaum)     

Lloyd SJ  LaPatra SE  Snekvik KR  Cain KD  Call DR 《Journal of fish diseases》2011,34(9):701-709

Strawberry disease (SD) is an inflammatory skin disorder in rainbow trout, Oncorhynchus mykiss (Walbaum). The aetiology of SD is unknown although the 16S rDNA sequence of a Rickettsia-like organism (RLO) has been associated with SD lesions using a nested PCR assay. In this study, we developed a Taqman quantitative PCR assay (qPCR) that targeted the RLO 16S rDNA sequence to examine the distribution of RLO relative to lesion status. We compared 18 lesion samples from 13 fish representing high or low lesion severity as judged by gross examination. QPCR results showed that there was a higher number of RLO sequences in high severity lesions (mean of 12,068 copies) compared with fewer copies of RLO sequence in low severity lesions (mean of 3287 copies, P = 0.012). Grossly normal skin samples (n = 13) from SD-affected fish were all negative by qPCR except two samples (121 and 139 copies). The qPCR assay described herein is a useful tool to investigate the role of RLO in SD in the absence of a culture system for RLO. Our results demonstrate a positive correlation between copy number and lesion severity consistent with the hypothesis that the RLO is the aetiologic agent of SD.  相似文献   

The effect of sample storage on the extraction of Cu,Zn, Fe,Mn and organic material from oxidized estuarine sediments     

Elizabeth A. Thomson  Samuel N. Luoma  Daniel J. Cain  Christopher Johansson 《Water, air, and soil pollution》1980,14(1):215-233

Concentrations of extractable Cu, Zn, Fe and Mn in oxidized estuarine sediment are influenced by the manner and time of storage between collection and extraction. No storage method tested completely preserves the initial chemical and physical characteristics of the sediment. Freezing or (for some extractions) drying are adequate methods of storage if sediments are to be extracted only with acids. However, if a variety of extractants is to be used, extractions should be conducted as soon as practical after collection.  相似文献   

Palynological Studies at Sodon Lake: I. Size-Frequency Study of Fossil Spruce Pollen     

Cain SA 《Science (New York, N.Y.)》1948,108(2796):115-117

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