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931.
Andrew Buskell 《Biology & philosophy》2016,31(3):435-446
Morin has written a rich and valuable book. Its main aim is to isolate the factors involved in maintaining behavioural lineages over time, and to understand how these factors might interact. In doing so, it takes issue with the abstract and idealised models and arguments of dual-inheritance theorists, which are alleged in this account to rely on an overly simplistic notion of imitative learning. Morin’s book is full of ethnographic, anthropological, and psychological research, and there is much to commend in it. However, Morin’s arguments against the dual-inheritance theorists are less convincing when put under scrutiny, and his positive picture which includes appeals to ostensive communication, intrinsic appeal and cultural attraction has some difficulties. I argue that when we contrast dual-inheritance theorists and Morin, we find that there may be fewer differences and greater commonalities than Morin’s book might suggest. 相似文献
932.
Torben Greve 《Acta veterinaria Scandinavica》2004,45(Z1):S13
Xenotransplantation of organs from the large domestic species will only be successful if the donor animals have been genetically modified, in particular regarding the α-Gal epitope, certain human complements (CD55 and CD59) and/or H-transferase. This requires, among other things, major embryo-technological efforts, and the rate of success is still far from an acceptable level in the domestic species. It is currently poor, but the progress is very good. In this brief review certain embryo-technological problems will be addressed with the focus on the pig as potential organ donor. In addition, certain views of the Danish ad hoc Committee on Gene Technology on xenotransplantation will be presented in this context as they are supposed to mirror the concern and the views of the issues important for the public and each individual. 相似文献
933.
Molecular tools were used to evaluate the hybrid status of a specimen with intermediate colour pattern between Halichoeres bivittatus and Halichoeres garnoti from Belize. Phylogenetic analyses of the two species, eight Halichoeres species from new and old world lineages and two outgroups showed that the study species are closely related and that H. garnoti is the maternal contributor to the putative hybrid specimen, based on partial mitochondrial COI data. Direct sequencing of
Intron 1 of the nuclear ribosomal protein S7 identified H. bivittatus as sister to H. garnoti with the putative hybrid specimen in an intermediate position, due to heterozygosity at nucleotides alternatively fixed in
the two putative parent species. This is consistent with the hybrid status of the specimen, with parental contributions from
both H. garnoti and H. bivittatus. These results, combined with no evidence of introgression between the two parent species (based on the mtDNA and the single
investigated nuclear marker) and the biogeography and ecology of these species suggests that this is a rare event with minimal
evolutionary implications. 相似文献
934.
Gerald Busch 《Bioenergy Research》2012,5(3):584-605
Based on regional stakeholder preferences and planning guidelines as allocation criteria for SRC, this study aims at providing
a transparent approach to evaluate multiple environmental effects and the regional significance of SRC systems. Using the
example of two poplar SRC-systems (4-year rotation, 9-year rotation) the potential effects on ground water supply, wind erosion,
and biodiversity aspects are evaluated in comparison to arable land for two selected municipalities in the district of Uelzen,
Germany. Building on fuzzy membership functions and simple fuzzy-logic rules, the qualitative multi-criteria assessment is
transparent and easily to adapt. This approach is transferable to other regions and spatial levels, since it derives from
commonly available data and scientific evidence. Results show that implementation of SRC could provide multiple beneficial
environmental effects, especially in areas with low landscape heterogeneity. The tools provided allow for a multi-criteria
evaluation of environmental effects, and reveal the sensitivity to distinct allocation patterns. Physiographical conditions
of the study area implicate a preference for mini-SRC systems. This is supported by smaller decline of annual deep percolation
water compared to maxi-SRC. On average, decline in groundwater recharge of mini-SRC (92mm a−1) is comparable to irrigated arable land (80mm a−1), which is common practice in the study area. Currently, the utilization of beneficial environmental SRC effects is quite
limited, since only 3 % of arable land is suitable for SRC implementation regarding farmers’ preferences for SRC allocation.
Allocation preferences could however change substantially with increasing incentives for SRC, e.g., due to regional bioenergy
schemes or “Greening” initiatives within the European Common Agricultural Policy, which is to be reformed by 2013. 相似文献
935.
Paul Bangirana Peter Allebeck Michael J Boivin Chandy C John Connie Page Anna Ehnvall Seggane Musisi 《BMC neurology》2011,11(1):96
Background
Infection with severe malaria in African children is associated with not only a high mortality but also a high risk of cognitive deficits. There is evidence that interventions done a few years after the illness are effective but nothing is known about those done immediately after the illness. We designed a study in which children who had suffered from severe malaria three months earlier were enrolled into a cognitive intervention program and assessed for the immediate benefit in cognitive, academic and behavioral outcomes. 相似文献936.
937.
Tipu Muhammad Imran Ashraf Muhammad Yasin Sarwar Nadeem Akhtar Muhammad Shaheen Muhammad Rashid Ali Sajjad Damalas Christos A. 《Journal of Plant Growth Regulation》2021,40(2):774-786
Journal of Plant Growth Regulation - Nickel (Ni) element is strongly phytotoxic at high concentrations for several plants, but due to its dual behavior and complicated chemistry, it has received... 相似文献
938.
Xue Bessie Su Menglu Wang Claudia Schaffner Olga O. Nerusheva Dean Clift Christos Spanos David A. Kelly Michael Tatham Andreas Wallek Yehui Wu Juri Rappsilber A. Arockia Jeyaprakash Zuzana Storchova Ronald T. Hay Adle L. Marston 《The Journal of cell biology》2021,220(7)
During mitosis, sister chromatids attach to microtubules from opposite poles, called biorientation. Sister chromatid cohesion resists microtubule forces, generating tension, which provides the signal that biorientation has occurred. How tension silences the surveillance pathways that prevent cell cycle progression and correct erroneous kinetochore–microtubule attachments remains unclear. Here we show that SUMOylation dampens error correction to allow stable sister kinetochore biorientation and timely anaphase onset. The Siz1/Siz2 SUMO ligases modify the pericentromere-localized shugoshin (Sgo1) protein before its tension-dependent release from chromatin. Sgo1 SUMOylation reduces its binding to protein phosphatase 2A (PP2A), and weakening of this interaction is important for stable biorientation. Unstable biorientation in SUMO-deficient cells is associated with persistence of the chromosome passenger complex (CPC) at centromeres, and SUMOylation of CPC subunit Bir1 also contributes to timely anaphase onset. We propose that SUMOylation acts in a combinatorial manner to facilitate dismantling of the error correction machinery within pericentromeres and thereby sharpen the metaphase–anaphase transition. 相似文献
939.
940.
Dr Christos A. Kontogiorgis Yanan Xu Dimitra Hadjipavlou-Litina Yuan Luo 《Free radical research》2013,47(10):1168-1180
The role of oxidative stress and free radicals in the development of Alzheimer's disease (AD) has been the focus of many recent studies. The role of hydrogen peroxide (H2O2) in AD is thought to be associated with Aβ (amyloid – β) damage in cells. A number of coumarin derivatives were previously found to be potent anti-inflammatory and antioxidant agents. Herein, these coumarin derivatives were tested as H2O2 scavengers with the DCF assay using two types of neuronal cells: (a) wild type (N2a) neuroblastoma cells and (b) APP/PS1 transgenic cell line expressing Aβ. Their scavenging activity was varied between the types of cell cultures and it was found to be concentration and time dependent in the mutant cells. Their protective role against cell death further supports this notion. These results suggest that these compounds could be used as a template in the design of new molecules with a possible role in AD. 相似文献