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141.
142.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing the global coronavirus disease 2019 (COVID-19) pandemic. Because complete elimination of SARS-CoV-2 appears difficult, decreasing the risk of transmission is important. Treatment with 0.1 and 0.05 ppm ozone gas for 10 and 20 hr, respectively, decreased SARS-CoV-2 infectivity by about 95%. The magnitude of the effect was dependent on humidity. Treatment with 1 and 2 mg/L ozone water for 10 s reduced SARS-CoV-2 infectivity by about 2 and 3 logs, respectively. Our results suggest that low-dose ozone, in the form of gas and water, is effective against SARS-CoV-2.  相似文献   
143.
Cytotechnology - Bone mass is regulated by osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Osteoporosis is a bone metabolism disorder in which bone mass decreases due to...  相似文献   
144.
Purpose

Bio-based recycling systems and agricultural production using recycled materials are often evaluated separately. This study performs an environmental and socio-economic life cycle assessment (LCA) of a food waste treatment and spinach farming system in Japan. The environmental and economic tradeoffs of introducing a recycling system and the net environmental benefit of the substitution of market fertilizer considering operation changes are also examined.

Methods

Three scenarios were developed and compared. In the conventional (CV) scenario, food waste is collected, incinerated, and disposed of in landfill, and the farmer uses market organic fertilizer. The on-site composting (OC) scenario processes food waste using an on-site garbage disposer and transports compost to a nearby spinach farmer. Food waste in the centralized composting (CC) scenario is transported to a centralized composting facility and resultant compost is sent to the farm. Primary data were obtained from field experiments and interviews. Non-greenhouse gas (GHG) emissions from the field and nitrogen leaching to water systems were simulated using the denitrification–decomposition (DNDC) model.

The environmental LCA targeted climate change, eutrophication, and waste landfill. An input–output analysis estimated socio-economic indicators, namely gross added value and employment inducement effect.

Results and discussion

The scenario with the lowest impact is the CC scenario. Climate change and eutrophication impacts are highest in the OC scenario and waste landfill impacts are most significant in the CV scenario. The weighted impact by LIME2 can be reduced by 47% in the CC scenario and 17% in the OC scenario due to the recycling of food waste instead of dumping in the landfill. The difference in socio-economic indicators between the scenarios was relatively small, although the CV scenario encouraged more employment. The substitution effect of composting, as well as the environmental impact reduction of replacing market organic fertilizer with compost, will result in 28.7% of the avoided impacts in GHG emissions.

Conclusions

Both composting scenarios are feasible from an environmental and socio-economic perspective when compared with conventional organic production, although there is a tradeoff between waste landfill and GHG emissions for the on-site composting system. However, the OC scenario needs to save electricity to improve its environmental competitiveness with the CV scenario. When considering the substitution effect of composting, it is recommended to take into account that agricultural operation also changes.

  相似文献   
145.
146.
Abstract

2-Bromoadenosine-substituted analogues of 2–5A, p5′A2′p-5′A2′p5′(br2A), p5′(br2A)2′p5′A2′p5′A, and p5′(br2A)2′p5′(br2A)2′p-S′(br2A), were prepared via a modification of a lead ion-catalyzed ligation reaction and were subsequently converted into the corresponding 5′-triphosphates. Both binding and activation of human recombinant RNase L by various 2-bromoadenosine-substituted 2–5A analogues were examined. Among the 2-bromoadenosine-substituted 2–5A analogues, the analogue with 2-bromoadenosine residing in the 2′-terminal position, p5′A2′p5′A2′p-5′(br2A), showed the strongest binding affinity and was as effective as 2–5A itself as an activator of RNase L. The CD spectrum of p5′A2′p-5′A2′p5′(br2A) was superimposable on that of p5′A2′p5′A2′p5′A, indicative of an anti orientation about the base-glycoside bonds as in naturally occurring 2–5A.  相似文献   
147.
Abstract

We have demonstrated that antisense phosphorothioate oligonucleotides (S-ODNs) inhibit influenza virus A replication in MDCK cells. Phosphorothioate and liposomally encapsulated oligonucleotides with two target sites (PB1 and PB2) were synthesized and tested for virus-induced cytopathogenicity effects by a MTT assay using MDCK cells. The liposomally encapsulated S-ODNs complementary to the sites of the PB2-AUG initiation codon showed highly inhibitory effects. On the other hand, the inhibitory effect of the liposomally encapsulated S-ODNs targeted to PB1 was considerably decreased in comparison with the PB2 target sites. The liposomally encapsulated oligonucleotides exhibited higher inhibitory activity than the free oligonucleotides. The activities of the modified oligonucleotides are effectively enhanced by using the liposomal carrier.  相似文献   
148.
Abstract

Incorporation of an azobenzene-4,4′-diamide group via a linker arm into the 3′-hydroxyl function of one oligonucleotide segment and the 5′-OH of other oligonucleotide has been described. The binding of the oligonucleotides containing the azobenzene linker was investigated by UV melting behaviors. The azobenzene linker has been shown to be useful as an effective bridge for stabilizing hairpin duplex and triplex.  相似文献   
149.
Quantitative trait locus (QTL) analyses have greatly enhanced our understanding of complex traits in rice (Oryza sativa). In parallel, the development of introgression lines has provided a powerful tool for elucidation of complicated genetic networks and identification of QTL. We recently developed a biotron breeding system that allows rapid indoor cultivation of rice plants. The system, however, has two relatively weak points in its application to marker-assisted breeding in rice: first, variation in generation times among cultivars; second, the low number of seeds produced by crosses. To compensate for these weaknesses, we propose utilizing cytoplasmic male sterility (CMS) and restorer (Rf) lines with a cv. Nipponbare genetic background. Through use of the Nipponbare genetic background, rice generation times of 2 months can be achieved regardless of any differences in the genetic background of the donor rice plant. This CMS–Rf system confers a high yield of hybrid seeds, avoids the need for emasculation and precludes accidental crosses. Our results demonstrate that this new methodology can markedly accelerate many different aspects of rice research, especially in functional genomics. The combination of biotron breeding system, early flowering habit and CMS will be of great value for screening candidate genes associated with QTL and for introducing useful QTL into elite cultivars.  相似文献   
150.
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