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41.
Luther Tweeten 《Agriculture and Human Values》1987,4(1):66-74
the personality of the farm sector is basically healthy and has many of the favorable attributes embodied in the image of the family farmer as self-reliant and independent; and as committed to fair play, due process, and democratic ideals. But a darker side of the farm personality traits has emerged in the course of American history. Social scientists for the most part have given little attention to negative personality traits of farmers and the goals, values, and beliefs that underlie these negative traits. The purpose of this essay is to address the issue. The conclusion is that social scientists must confront myths that may have made life tolerable for many farmers but also have provided a psychological and ideological climate where paranoia, scapegoating, violence, armed confrontation, intimidation, and fear reflect the dark side of the farm personaility. 相似文献
42.
Histologically, multiple wart-like papules or hyperkeratotic plaques on the ear pinnae from 4 dogs were characterized as idiopathic benign lichenoid keratosis. Common histologic features included a discrete lesion of irregular and papillated epidermal hyperplasia with a moderate diffuse lichenoid interface inflammatory infiltrate consisting of lymphocytes and plasma cells. There was also focal hydropic degeneration of the epidermal basal cell layer, pigmentary incontinence, and mixed orthokeratotic and parakeratotic hyperkeratosis. In all 4 dogs, the pinnal lesions were unilateral and asymptomatic. Complete surgical excision was curative. 相似文献
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44.
Irradiation of semen doses with LED‐based red light in a photo chamber does not improve in vitro quality of thermically stressed boar spermatozoa 下载免费PDF全文
A Luther X Le Thi J Schäfer M Schulze D Waberski 《Reproduction in domestic animals》2018,53(4):1016-1019
Recent reports indicate that stimulation of liquid‐stored boar semen with red LED‐based light improves sperm quality and reproductive performance in sow herds. So far, in vitro data after LED stimulation of whole semen doses are lacking. In this study, the effect of LED light exposure on the in vitro quality of boar spermatozoa after storage and thermic incubation was examined. Boar semen doses were stored at 17°C (n = 10) or 5°C (n = 6) in Beltsville Thawing Solution extender and then exposed to red LED light using a commercial photo chamber. During a subsequent long‐term incubation at 38°C, neither sperm kinematic parameters nor mitochondria function or membrane integrity differed between control and treated samples (p > .05). It is concluded that stimulation of semen doses in the LED‐photo chamber does not improve quality of thermically stressed boar sperm in vitro. Other than the sperm traits tested here might be involved in the previously reported improvement of in vivo fertility. 相似文献
45.
46.
Moore J Hao Z Zhou K Luther M Costa J Yu LL 《Journal of agricultural and food chemistry》2005,53(17):6649-6657
Consumers' desires to either reduce the risk of or manage a specific health condition through improved diet have stimulated the research of agricultural products for their potential health beneficial components such as tocopherols and natural antioxidants. Soft wheat is one of the major crops in Maryland, with little information available about its potentially beneficial components. This study examined eight selected Maryland-grown soft wheat varieties or experimental lines for their potential beneficial components including tocopherols, carotenoids, total phenolics and phenolic acids and their antioxidant properties, including Fe(2+) chelating capacity and free radical scavenging activities against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*) ), radical cation ABTS(*)(+), and oxygen radical (ORAC). The results showed that all tested soft wheat grain samples contained alpha-tocopherol, with a range of 3.4-10.1 microg/g. Lutein was the primary carotenoid present in the grain samples at a level of 0.82-1.14 microg/g, along with significant amounts of zeaxanthin and beta-carotene. Vanillic, syringic, p-coumaric, and ferulic acids were found in soluble free, soluble conjugated, and insoluble bound forms in the grain extracts, with ferulic acid as the predominant phenolic acid. The eight soft wheat varieties differed in their antioxidant properties. The tested wheat grain samples exhibited ED(50) values against DPPH(*) of 23-27 mg of grain equiv/mL, ORAC of 32.9-48 micromol of Trolox equiv (TE)/g, and ABTS(*)(+) scavenging capacity of 14.3-17.6 micromol of TE/g. These data suggest the possibility of producing soft wheat varieties rich in selected health beneficial factors for optimum human nutrition though breeding programs. 相似文献
47.
The effectiveness of measuring petiole sap nitrate-nitrogen concentration (PSNC) using ion selective electrode (ISE) has been scrutinized due to claims that PSNC poorly predicts leaf tissue nitrogen concentration (LTNC) or crop yield. This study evaluated the relationship among PSNC, LTNC, and marketable yield of tomato (Solanum lycopersicum L.). Two tomato trials were conducted using seepage irrigation and controlled-release fertilizer (CRF) in fall 2011 and 2012. At 15 days intervals, six most recently mature leaves were collected to measure PSNC and LTNC. PSNC and LTNC declined throughout the growing seasons, but PSNC was affected by weather. PSNC and LTNC were correlated (P = 0.0001, r = 0.38), though not meaningfully. PSNC and LTNC correlated negatively and positively with crop yield in most correlations, respectively. Correlations of CRFs and soluble fertilizers (SFs) separately, did not improve relationships. Measuring LTNC may be a more reliable nutrient management tool compared to PSNC measured using an ISE. 相似文献
48.
Streptococcus uberis is a significant cause of bovine mastitis throughout the world. Previous work from our laboratory demonstrated that S. uberis adhesion molecule (SUAM) is an important factor in adherence to and internalization of S. uberis into bovine mammary epithelial cells. Antibodies directed against SUAM significantly reduced bacterial adherence to and internalization into bovine mammary epithelial cells implying that SUAM is surface exposed. Objectives of this research were to: (1) predict surface exposed peptides, and (2) select peptide sequences for production of synthetic peptides with the final aim of evaluating their role in adherence and internalization and immunogenic potential. The Kyte/Doolittle hydropathicity prediction method; Chou/Fasman β-turn prediction method; and output from Coils, Paircoil and MultiCoil scores for prediction of secondary and tertiary structures were used. Prediction algorithms resulted in identification of five overlapping regions of the SUAM sequence with the most hydrophilic valleys and the highest peaks for β-turns. The five 15-mer SUAM epitopes selected by bioinformatic analysis were produced to evaluate the immunogenic value and pathogenic role of these putative domains. Peptides were bound to fluorescent latex beads, incubated with MAC-T bovine mammary epithelial cells, and internalization into MAC-T cells was evaluated using confocal laser and transmission electron microscopy. All peptides evaluated induced some degree of internalization of fluorescent beads into MAC-T cells; however, 2 peptides induced significantly more internalization of fluorescent beads than the other peptides evaluated. These peptides, designated III and IV, were located in the central region of SUAM, between two coiled-coil regions. Convalescent sera were tested against these biotinylated peptides for SUAM specific immune response using an indirect ELISA format. Among the 5 peptides evaluated, peptides I, II and V elicited significant serological response suggesting that the N-terminal region (peptide I), central region (peptide II) and C-terminal region (peptide V) are immunodominant epitopes of SUAM. Results will be useful to design immunotherapeutic tools based on immunodominant epitopes. 相似文献
49.
From tides to mixing along the Hawaiian ridge 总被引:2,自引:0,他引:2
Rudnick DL Boyd TJ Brainard RE Carter GS Egbert GD Gregg MC Holloway PE Klymak JM Kunze E Lee CM Levine MD Luther DS Martin JP Merrifield MA Moum JN Nash JD Pinkel R Rainville L Sanford TB 《Science (New York, N.Y.)》2003,301(5631):355-357
The cascade from tides to turbulence has been hypothesized to serve as a major energy pathway for ocean mixing. We investigated this cascade along the Hawaiian Ridge using observations and numerical models. A divergence of internal tidal energy flux observed at the ridge agrees with the predictions of internal tide models. Large internal tidal waves with peak-to-peak amplitudes of up to 300 meters occur on the ridge. Internal-wave energy is enhanced, and turbulent dissipation in the region near the ridge is 10 times larger than open-ocean values. Given these major elements in the tides-to-turbulence cascade, an energy budget approaches closure. 相似文献
50.
Cheng Z Zhou H Luther M Yin JJ Yu LL 《Journal of agricultural and food chemistry》2008,56(13):5033-5042
Three wheat antioxidant fractions were investigated for their potential effects on oxygen diffusion-concentration products in liposomes prepared with egg yolk phosphatidycholine (yolk PC) and rat liver PC (liver PC), using the electron spin resonance (ESR) oximetry method with 2,2'-azobis(2-aminopropane) dihydrochloride (AAPH) and 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN) as radical generators. Both water-soluble wheat antioxidant (WWA) and the second lipophilic antioxidant (LWA2) fractions were able to inhibit oxygen diffusion-concentration product induced by either AAPH or AMVN. The first lipophilic wheat antioxidant (LWA1) fraction only showed antioxidant activity in yolk PC liposomes with AAPH as the radical initiator but had pro-oxidant activity under other testing conditions. Both liposome composition and radical initiator altered the antioxidative properties of WWA, LWA1, and LWA2. WWA also showed the strongest DPPH(*) scavenging capacity on a per grain weight basis. HPLC analysis showed that WWA had a much higher level of total phenolic acids, which may partially explain their antioxidant properties. In addition, wheat antioxidants significantly down-regulated the mRNA of HMG-CoA reductase, the key enzyme for cholesterol biosynthesis, and up-regulated the mRNA of cholesterol 7alpha-hydroxylase (CYP7A1), the key enzyme for cholesterol metabolism, in primary rat hepatocytes. These data indicated the potential of wheat antioxidants in reducing the risk of atherosclerosis through multimechanisms. 相似文献