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11.
《Food Control》2017
To test the market viability of a non-GMO topical RNAi insect control, we conducted a Willingness-To-Pay (WTP) survey in the USA, Canada, Australia, France, and Belgium to elicit whether consumers need a premium or discount for: (1) a hypothetical GMO rice variety using the Bacillus thuringiensis (Bt) gene for insect control; and (2) a hypothetical non-GMO rice variety using topical RNAi spray for insect control. The survey was designed based on a Multiple Price List (MPL) format where respondents selected their preferred insect control technology; i.e., conventional, GMO Bt, or non-GMO RNAi, at different prices. Participants' responses were analyzed using an interval regression model to generate WTP premiums and discounts for each country with control variables for demographic influences. Further, we asked consumers their Willingness-To-Consume (WTC) food produced with GM and RNAi technologies respectively and evaluated WTC differences using a McNemar matched pairs test in each country. The results from our study clearly show that: (1) consumers in the USA, Canada, Australia, and France still require a discount for rice produced with topical RNAi compared to conventionally-produced rice (p < 0.05), (2) consumers in the USA, Canada, Australia, France, and Belgium would need an additional 30–40% discount to purchase Bt rice over rice produced with topical RNAi (p < 0.05), and (3) consumers in all countries were more willing to consume rice produced with non-GM RNAi than with GM Bt technology (p < 0.05). These findings suggest consumers differentiate among biotechnology solutions and consumers may prefer topical RNAi insect control to transgenic GMO insecticides. 相似文献
12.
PODEM,FANandSOCRATESalgorithmsallpresentafewstrategiesacceleratingthetestpatterngenerationbasedoncircuitstructure.PODEMalgo rithm[1]introducesbacktrackingtechnology,anditre ferstestgenerationtoanimplicitenumerationprobleminn dimensionalspacesuchthatitbrea… 相似文献
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Emine Kaplanoglu Igor Kolotilin Rima Menassa Cam Donly 《International journal of molecular sciences》2022,23(7)
Plant-mediated RNA interference (RNAi) holds great promise for insect pest control, as plants can be transformed to produce double-stranded RNA (dsRNA) to selectively down-regulate insect genes essential for survival. For optimum potency, dsRNA can be produced in plant plastids, enabling the accumulation of unprocessed dsRNAs. However, the relative effectiveness of this strategy in inducing an RNAi response in insects using different feeding mechanisms is understudied. To investigate this, we first tested an in vitro-synthesized 189 bp dsRNA matching a highly conserved region of the v-ATPaseA gene from cotton mealybug (Phenacoccus solenopsis) on three insect species from two different orders that use leaf-chewing, lacerate-and-flush, or sap-sucking mechanisms to feed, and showed that the dsRNA significantly down-regulated the target gene. We then developed transplastomic Micro-tom tomato plants to produce the dsRNA in plant plastids and showed that the dsRNA is produced in leaf, flower, green fruit, red fruit, and roots, with the highest dsRNA levels found in the leaf. The plastid-produced dsRNA induced a significant gene down-regulation in insects using leaf-chewing and lacerate-and-flush feeding mechanisms, while sap-sucking insects were unaffected. Our results suggest that plastid-produced dsRNA can be used to control leaf-chewing and lacerate-and-flush feeding insects, but may not be useful for sap-sucking insects. 相似文献
15.
苟素 《纺织高校基础科学学报》2011,24(2):250-252,269
Vk∈ N+,l<k≤9,数列{a(k,n)}称作Smarandache kn数字数列,如果该数列中的每一个数都可以分成两部分,那么第二部分是第一部分的k倍,例如3n数字数列{α(3,n)}定义为{13,26,39,412,515,618,721,824,…}.利用初等及组合方法研究Smarandache kn数字数列... 相似文献
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Siyuan Zhou Shiowshuh Sheen Yu‐Hsin Pang LinShu Liu Kit L. Yam 《Journal of food science》2013,78(5):M725-M730
Salmonella contamination on raw shrimp is a big food safety concern in the United States currently. This research evaluated the inhibition effects of vapor phase thymol, modified atmosphere (MA), and their combination against Salmonella spp. on raw shrimp. Growth profiles of a Salmonella spp. cocktail (6 strains), inoculated onto the surface of raw shrimp, treated with vapor phase thymol at 3 levels (0, 0.8, and 1.6 mg/L), or MA (59.5% CO2 + 39.5% N2 + 1% O2), both alone and in combination, at 3 temperatures (8, 12, and 16 ºC), were determined. Lag time and maximum growth rate of Salmonella spp. under each treatment were obtained using Baranyi and Roberts models. Results indicated that both vapor phase thymol and MA treatments alone inhibited the growth potential of Salmonella spp. effectively, extending the lag time by 10% to 100% and reducing the maximum growth rate by 14% to 71% compared with controlled samples at experimental temperatures (8, 12, and 16 ºC). Combination treatments of vapor phase thymol and MA exhibited greater inhibition effectiveness than each individual treatment and a synergistic antimicrobial effectiveness could be observed on the lag time extension. To the maximum, at 12 ºC, lag time of Salmonella spp. was extended 59.6% more by the combination treatment of 0.8 mg/L thymol + MA (36.97 h) than those effects combined from 0.8 mg/L thymol treatment and MA treatment alone (23.16 h in total). This combination strategy could be potentially utilized for Salmonella inhibition during the long distance and temperature‐abused raw shrimp import process. Practical Application The vapor phase thymol + MA combination strategy could be potentially applied in temperature‐abused and long‐distance raw shrimp import process to retard the Salmonella spp. growth, therefore reducing its import rejection rate as well as enhancing its food safety level to the consumers’ concerns. 相似文献
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针对标准遗传算法用于K-means优化聚类存在的问题,提出了一种基于组合优化方法的K-means聚类算法.实验结果表明:基于组合优化方法的K-means优化聚类算法效率较高,结果较好. 相似文献
18.
纯梁油田两种破乳剂联用的高含水原油热-化学破乳技术 总被引:3,自引:0,他引:3
纯梁油田各油气所产原油的油质(含蜡量),含水率及油温不同,将13种商品破乳剂用于纯梁各油区原油及混合油的破乳,筛选出了4种性能优良的破乳剂。将这4种破乳剂两两复配,用于混合油的破乳,最后筛选出以改性咪唑啉为起始剂的高聚物类破乳剂BSH-06和以改性树脂为起始剂的嵌段聚醚类破乳剂BCL-405。实施了联合使用这两种破乳剂的原油热-化学破乳脱水现场试验;在纯东集油计量站,在油温35℃,原油含蜡15%-20%的高含水量油中加入BSH-06,在纯西集油计量站,在油温55℃,原油含量20%,乳化水含量高的原油中加入BCL-405,加量100-80mg/L,在长3-4km的管道输送过程中破乳,在原油处理站两种原油混合后进入一级,二级沉降罐,沉降时间约4h,油水分离,原油含水降至≤0.5%,可以不再进行电脱水而直接外输,脱出污水含油量<100mg/L。这种不同原油各用合适的破乳剂管道破乳,混合沉降脱水的热-化学破乳脱水技术,已在纯梁油田广泛应用。 相似文献
19.
Priti Tagde Agnieszka Najda Kalpana Nagpal Giriraj T. Kulkarni Muddaser Shah Obaid Ullah Sebastian Balant Md. Habibur Rahman 《International journal of molecular sciences》2022,23(5)
Breast cancer is one of the most common types of cancer among women globally. It is caused by mutations in the estrogen/progesterone receptors and conventional treatment methods are commonly utilized. About 70–80 percent of individuals with the early-stage non-metastatic disease may be cured. Conventional treatment is far less than the optimal ratio, as demonstrated through the high mortality rate of women with this cancer. However, conventional treatment methods like surgery, radiotherapy, and chemotherapy are not as effective as expected and lead to concerns about low bioavailability, low cellular uptake, emerging resistance, and adverse toxicities. A nanomedicine-based approach is a promising alternative for breast cancer treatment. The present era is witnessing rapid advancements in nanomedicine as a platform for investigating novel therapeutic applications and modern intelligent healthcare management strategies. This paper focuses on nanomedicine-based therapeutic interventions that are becoming more widely accepted for improving treatment effectiveness and reducing undesired side effects in breast cancer patients. By evaluating the state-of-the-art tools and taking the challenges involved into consideration, various aspects of the proposed nano-enabled therapeutic approaches have been discussed in this review. 相似文献