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31.
M. Andrew Holowchak 《Agriculture and Human Values》2011,28(4):497-506
Scholars today are divided on the motivation behind what is often called Jefferson’s “moral agrarianism”. On the one hand,
some scholars take Jefferson at his word when he mentions that agrarianism is a moral vision. For these individuals, Jefferson’s
agrarianism is a moral vision and an indispensible part of the good life. On the other hand, other scholars maintain that
Jefferson’s moral agrarianism is merely a bit of propaganda that insidiously sheaths a political or economic ideal. For them,
Jefferson is through and throughout a politician, and expressions of agrarianism as a moral ideal amount to mere cant. In
this paper, I examine arguments for and against Jefferson’s moral agrarianism. I defend the position that Jefferson was an
aboveboard moral agrarianist and that the ideal of agrarianism was not just one that was suited for Americans, given their
surfeit of land and want of laborers, but an ideal that also applied universally. I end with thoughts on Jefferson’s recognition
of the rise of manufacturing in American cities throughout his life. 相似文献
32.
This study was carried out to optimize dyeing conditions of unripe Citrus Unshiu extract on silk fabric and to evaluate antimicrobial
activity of the dyed fabric for its potential use as a functional natural dye. Unripe fruits of Citrus Unshiu in Jeju Island,
Korea, extracted in 80 % Ethanol solution to final solid dye powder were dyed on silk fabric under a variety of conditions
such as dye bath concentrations, temperature, and dyeing duration together with mordanting. Dyeing fastness properties to
washing, rubbing, perspiration, and light were tested and the antimicrobial activities of the dyed fabric against Staphylococcus
aureus and Klebsiella pneumoniae were investigated quantitatively. As results, the fabric showed the maximum dye uptake (K/S) under the conditions of 80 °C for temperature, 30 min for duration, and 600 % (o.w.f.) for dye concentration. Both pre-
and post-mordanting seemed not to be effective on increasing K/S values of the dyed silk fabrics under the optimum dyeing conditions. Fastness ratings to washing, rubbing, and perspiration
were all very good (4–5 grades) for both 300 and 600 % dyed silk fabrics. Excellent antimicrobial activities over 99 % reduction
rate against two both bacteria were exhibited for all of dyed fabrics undergone more than 300 % of dye concentration. From
these results, it was concluded that the dye concentration of 300 % of unripe Citrus Unshiu could be employed to produce antimicrobial
silk fabric. Furthermore, to get more saturated shades on the fabric by the citrus, higher dye concentration such as 600 %
was available as well. 相似文献
33.
34.
Arne Stensvand Håvard Eikemo Robert C. Seem David M. Gadoury 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(1):173-178
Darkness suppresses ascospore release in Venturia inaequalis, but the impact of light levels during the extended twilight and dusk that typify Nordic spring conditions is poorly understood.
Volumetric spore traps were operated at two different locations in Norway over several years. During the season of asocspore
release (approximately 1 April to 30 June), on 25 occasions when rain started during night (after 23:00 h and before 04:00 h)
and leaves remained wet until at least midnight the following day, the cumulative percentage of spores trapped at sunrise
did not exceed 1%, irrespective of temperature. Three hours after sunrise, cumulative ascospore release reached 0.8%, 3.0%,
and 8.1% at temperatures of 0 to 5°C, 5 to 10°C, and >10°C, respectively, and 50% release occurred at 11, 9, and 8 h after
sunrise. Additional field and laboratory studies indicated that the protracted dawn and dusk of Nordic latitudes, either alone
or in combination with low temperatures, does not substantially alter previously reported patterns of ascospore release. 相似文献
35.
Donna S. Smith Solke H. De Boer 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(3):405-412
A previously published TaqMan PCR test for R. solanacearum race 3 biovar 2 was modified to enable both the validation of negative results and the confirmation of positive results in
a closed-tube system. Negative results were validated through the use of a reaction control plasmid, designated pRB2C2, which
was designed to generate a 94bp product using the same amplimers targeting the primary diagnostic 68bp sequence in R. solanacearum race 3 biovar 2 DNA. SYBR Green was included in the reaction mix to facilitate the identification of post-reaction products
using melt peak analysis. The 94bp reaction control had a melt peak temperature of about 90°C, while the diagnostic target
amplicon had a melt peak temperature of about 83°C; thus positive results could be easily confirmed and distinguished from
the reaction control product. Addition of pRB2C2 at 100 copies per reaction had no effect on the sensitivity of the TaqMan
assay for R. solanacearum race 3 biovar 2, and the modified assay successfully detected R. solanacearum race 3 biovar 2 in infected, asymptomatic tomato stems and leaves as well as in potato tubers and stems. 相似文献
36.
37.
38.
In Western Kenya, smallholder dairy production is becoming incrementally commercialized through the commodification and sale of milk through formal market channels. While commercialization is often construed as a way to boost rural livelihoods through increased income from milk, emerging evidence suggests that married women are not directly benefiting from formal milk market participation. This critical issue of gender power imbalance has been framed by development interventions in economic efficiency and social justice perspectives, but thus far interventions in the sector have not addressed how underlying social-market mechanisms embedded in gendered ideology influence smallholder engagement in dairy commercialization. Drawing on feminist theories of power and social embeddedness, this study investigates how gendered power relationships materialize and influence formal milk marketing engagement and practices in Western Kenya. Facilitated discussion groups with smallholder farmers revealed the gendered ideologies and norms that ascribe masculinized meaning to cattle, milk, and commercial enterprise. Key informant interviews with commercial dairy management and farmers were used to identify current practices for increasing women’s formal market participation—namely, direct payments to women for milk deliveries. Findings from this study indicate that cattle and formal dairy market participation are imbued with gendered meaning that create legitimacy around men’s privilege over dairy proceeds. Interventions in the sector aimed at addressing gender power imbalances must acknowledge this dynamic, and accept the social trade-offs and gendered costs of dairy commercialization. 相似文献
39.
Luz Yineth Ortiz-Rojas Giovanni Chaves-Bedoya 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(4):883-894
Papaya ringspot virus is an RNA virus that belongs to the genus Potyvirus, family Potyviridae and affects both papaya and cucurbits, causing great economic losses. PRSV isolates are divided into biotypes P and W; both biotypes naturally infect plants in the family Cucurbitaceae, whereas the P type also naturally infects papaya (Carica papaya L). In the present study, we report the full-length genome sequence of two PRSV-P isolates sampled from the Campo Hermoso (PRSV-CH) and Villa del Rosario (PRSV-VR) localities in Norte de Santander, Colombia. The genomes of these PRSV isolates are 10,326 nt in length and have a predicted ORF of 3344 aa. The identity among Colombian PRSV isolates is 96.9% and 97.3% at the nucleotide and deduced amino acid levels, respectively. PRSV isolates from China had the lowest identity at 78.3% and 89.2% (nucleotide-amino acid), whereas the highest identities were detected in PRSV isolates from Mexico, Venezuela and Hawaii. At the polyprotein level, the amino acid composition surrounding the active polyprotein cleavage sites differ in the Colombian PRSV sequences. The predicted cleavage site in P1/HC-Pro is LEQY/N – LEQY/S instead of MEQY/N. Both of the Colombian PRSV isolates have a putative recombination event in the P1 coding region, which is common in all PRSV isolates from the American continent. The new full-length PRSV sequences from Colombia provide a better understanding of the dynamics of papaya ringspot virus infections in papaya in Colombia and worldwide. 相似文献
40.