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951.
952.
Maya Almaraz Maegen Simmonds F. Garrett Boudinot Alan V. Di Vittorio Nina Bingham Sat Darshan S. Khalsa Steven Ostoja Kate Scow Andrew Jones Iris Holzer Erin Manaigo Emily Geoghegan Heath Goertzen Whendee L. Silver 《Global Change Biology》2023,29(21):5988-5998
The ongoing climate crisis merits an urgent need to devise management approaches and new technologies to reduce atmospheric greenhouse gas concentrations (GHG) in the near term. However, each year that GHG concentrations continue to rise, pressure mounts to develop and deploy atmospheric CO2 removal pathways as a complement to, and not replacement for, emissions reductions. Soil carbon sequestration (SCS) practices in working lands provide a low-tech and cost-effective means for removing CO2 from the atmosphere while also delivering co-benefits to people and ecosystems. Our model estimates suggest that, assuming additive effects, the technical potential of combined SCS practices can provide 30%–70% of the carbon removal required by the Paris Climate Agreement if applied to 25%–50% of the available global land area, respectively. Atmospheric CO2 drawdown via SCS has the potential to last decades to centuries, although more research is needed to determine the long-term viability at scale and the durability of the carbon stored. Regardless of these research needs, we argue that SCS can at least serve as a bridging technology, reducing atmospheric CO2 in the short term while energy and transportation systems adapt to a low-C economy. Soil C sequestration in working lands holds promise as a climate change mitigation tool, but the current rate of implementation remains too slow to make significant progress toward global emissions goals by 2050. Outreach and education, methodology development for C offset registries, improved access to materials and supplies, and improved research networks are needed to accelerate the rate of SCS practice implementation. Herein, we present an argument for the immediate adoption of SCS practices in working lands and recommendations for improved implementation. 相似文献
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Summary Histophotometric examination was carried out on nuclei of lymphocytes in human peripheral blood, which were subjected to various tests in order to assess the acrolein-Schiff method as a possible DNA specific reaction, in comparison with the traditional Feulgen reaction. Special attention was paid to the degree of difference between responses attributable to a direct Schiff reaction obtained in the fraction of nuclear proteins after treatment with acrolein. From the results obtained it appears that an acrolein-Schiff reaction, following extraction of proteins, may be considered a qualitative reaction for DNA. Our findings also show that there is no relationship between the degree of response to the acrolein-Schiff reaction and that to the Feulgen reaction, which is to be expected in view of the different mechanisms of the two reactions. 相似文献
955.
Dr. Giancarlo Pizza Dimitri Viza Caterina De Vinci Aldopaolo Palareti Diego Cuzzocrea Vittorio Fornarola Roberto Baricordi 《Biotherapy》1996,9(1-3):67-72
Forty-four patients suffering from genital (22) and labial (22) herpes were orally treated with HSV-1/2-specific transfer
factor(TF). TF was obtained by in vitro replication of a HSV-1/2-specific bovine dialysable lymphocyte extract. Treatment
was administered bi-weekly the first 2 weeks, and then weekly for 6 months, most patients received 2–3 courses. The total
observation period for all patients before treatment was 26660 days, with 544 relapses, and a relapse index of 61.2, whereas
the cumulative observation period during and after treatment was 16945 days, with a total of 121 relapsing episodes and a
cumulative RI of 21.4 (P<0.0001). Results were equally significant when the 2 groups of patients (labial and genital) were
considered separately. These observations confirm previous results obtained with bovine HSV-specific TF, and warrant further
studies to establish HSV-specific TF as a choice of treatment for preventing herpes recurrences. 相似文献
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Vittorio Gremigni 《Journal of morphology》1976,149(2):265-277
Oogenesis of the fresh-water triclad Dugesia dorotocephala has been studied by electron microscopical methods, with particular regard to the genesis and composition of the so-called “Balbiani body.” Its origin is clearly recognizable in young oocytes where the few mitochondria present seem to gather at the level of the perinuclear ooplasm. Here they surround dense masses of finely granular, fibrillar material probably coming from the nucleus. During the previtelloge ic period, mitochondria rapidly increase in number while the dense masses progressively dissolve. In the vitellogenic oocytes the Balbiani body shows its final configuration: it appears as a large area (up to 15-20 pm in diameter) consisting of innumerable densely packed mitochondria, some smooth vesicles and free ribosomes. This aggregate of cytoplasmic organelles remains unmodified in the mature oocytes. The function of the “Balbiani body” of D. dorotocephala is as yet unclear; it can only be asserted that it is not correlated with yolk production in which the endoplasmic reticulum and the Golgi complex are involved. 相似文献
960.