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61.
Lysine succinylation is a post-translational modification which alters protein function in both physiological and pathological processes. Mindful that it requires succinyl-CoA, a metabolite formed within the mitochondrial matrix that cannot permeate the inner mitochondrial membrane, the question arises as to how there can be succinylation of proteins outside mitochondria. The present mini-review examines pathways participating in peroxisomal fatty acid oxidation that lead to succinyl-CoA production, potentially supporting succinylation of extramitochondrial proteins. Furthermore, the influence of the mitochondrial status on cytosolic NAD+ availability affecting the activity of cytosolic SIRT5 iso1 and iso4—in turn regulating cytosolic protein lysine succinylations—is presented. Finally, the discovery that glia in the adult human brain lack subunits of both alpha-ketoglutarate dehydrogenase complex and succinate-CoA ligase—thus being unable to produce succinyl-CoA in the matrix—and yet exhibit robust pancellular lysine succinylation, is highlighted. 相似文献
62.
Nitrogen dynamics during the seed-filling period in safflower under dryland Mediterranean conditions
Koutroubas Spyridon D. Damalas Christos A. Fotiadis Sideris 《Nutrient Cycling in Agroecosystems》2021,121(2-3):271-282
Nutrient Cycling in Agroecosystems - Precise knowledge of safflower (Carthamus tinctorius L.) nitrogen (N) dynamics is essential to optimize crop nutrition and minimize environmental impacts of... 相似文献
63.
The five papers in this special issue are extended versions of papers presented at the Hot Chips conference in August 1008. 相似文献
64.
We consider the notion of strong equivalence [V. Lifschitz, D. Pearce, A. Valverde, Strongly equivalent logic programs, ACM Transactions on Computational Logic 2 (4) (2001) 526-541] of normal propositional logic programs under the infinite-valued semantics [P. Rondogiannis, W.W. Wadge, Minimum model semantics for logic programs with negation-as-failure, ACM Transactions on Computational Logic 6 (2) (2005) 441-467] (which is a purely model-theoretic semantics that is compatible with the well-founded one). We demonstrate that two such programs are strongly equivalent under the infinite-valued semantics if and only if they are logically equivalent in the corresponding infinite-valued logic. In particular, we show that strong equivalence of normal propositional logic programs is decidable, and more specifically coNP-complete. Our results have a direct implication for the well-founded semantics since, as we demonstrate, if two programs are strongly equivalent under the infinite-valued semantics, then they are also strongly equivalent under the well-founded semantics. 相似文献
65.
Haris Doukas Alexandra G. Papadopoulou Christos Nychtis John Psarras Nicole van Beeck 《Renewable & Sustainable Energy Reviews》2009,13(3):682-688
The European Union (EU) from the beginning of 2007 has focused its emphasis on the development of a new policy that puts energy back at the heart of EU action. Indeed, it has very often been stated that the difficulty and complexity of achieving green energy targets in the EU will require strengthened measures to promote implementation of new energy technologies (NET), as well as measures to support the related energy Research and Technology Development (R&TD). Often forgotten is the fact, that most of all, a European-wide co-ordinated forum is needed to continuously develop and sophisticate the monitoring and methodology results, bringing together specialised statisticians, energy researchers and experts on energy socio-economics. Today a nebulous picture prevails on the existence of categorized data with regards to energy Research and Technology Development (R&TD) expenditure. In this context, aim of this paper is the presentation of energy R&TD data collection strategies, as well as the related findings for the Greek energy market. 相似文献
66.
Christos Baloukas Author Vitae Jose L. Risco-Martin Author Vitae Christophe Poucet Author Vitae Lazaros Papadopoulos Author Vitae Juan Lanchares Author Vitae 《Journal of Systems and Software》2009,82(4):590-602
Modern multimedia application exhibit high resource utilization. In order to efficiently run this kind of applications in embedded systems, the dynamic memory subsystem needs to be optimized. A key role in this optimization is played by the dynamic data structures that reside in every real-life application. This paper presents a novel and automated way to optimize dynamic data structures. The search space is pruned using genetic algorithms that converge to the best multilayered data structure implementation for the targeted applications. 相似文献
67.
A new approach is presented for elastic registration of medical images, and is applied to magnetic resonance images of the brain. Experimental results demonstrate very high accuracy in superposition of images from different subjects. There are two major novelties in the proposed algorithm. First, it uses an attribute vector, i.e., a set of geometric moment invariants (GMIs) that are defined on each voxel in an image and are calculated from the tissue maps, to reflect the underlying anatomy at different scales. The attribute vector, if rich enough, can distinguish between different parts of an image, which helps establish anatomical correspondences in the deformation procedure; it also helps reduce local minima, by reducing ambiguity in potential matches. This is a fundamental deviation of our method, referred to as the hierarchical attribute matching mechanism for elastic registration (HAMMER), from other volumetric deformation methods, which are typically based on maximizing image similarity. Second, in order to avoid being trapped by local minima, i.e., suboptimal poor matches, HAMMER uses a successive approximation of the energy function being optimized by lower dimensional smooth energy functions, which are constructed to have significantly fewer local minima. This is achieved by hierarchically selecting the driving features that have distinct attribute vectors, thus, drastically reducing ambiguity in finding correspondence. A number of experiments demonstrate that the proposed algorithm results in accurate superposition of image data from individuals with significant anatomical differences. 相似文献
68.
69.
Moderate levels of reactive oxygen species (ROS) have been implicated as second messengers in a number of biochemical pathways, and in animal cells have been associated with the activation of the heat shock response (HSR). Here, using an intracellular probe, we demonstrate that differential accumulation of ROS in the yeast Saccharomyces cerevisiae is strongly associated with differential induction of an HS reporter gene over a range of heat shock temperatures. There was a good correlation between cellular ROS levels and the levels of HS-induced reporter gene expression between 37 degrees C and 44 degrees C, both reaching maximal values at 41 degrees C. Furthermore, the addition of 150 microM H2O2 to the yeast cells during heat treatment resulted in a 3 degrees C decrease in the temperature required for maximal induction of the HS expression vector--an increased HS sensitivity that corresponded to a concomitant increase in ROS levels at these lower HS temperatures. Conversely, cells treated with 10 mM of the antioxidant ascorbic acid required a temperature that was 2 degrees C above that required in untreated controls for maximal induction of the HS expression vector. This decreased HS sensitivity corresponded to a decrease in ROS levels at these higher HS temperatures. Finally, cell viability assays reveal that intrinsic thermotolerance remains high in control cells despite concomitant decreases in HS-reporter gene expression and ROS accumulation between 41 degrees C and 44 degrees C. We conclude that the sensitivity of the yeast HSR is strongly associated with ROS accumulation, and suggest that ROS-mediated signalling ensures cooperation between the HS and the antioxidant responses. 相似文献
70.
Determining correspondence in 3-D MR brain images using attribute vectors as morphological signatures of voxels 总被引:3,自引:0,他引:3
Finding point correspondence in anatomical images is a key step in shape analysis and deformable registration. This paper proposes an automatic correspondence detection algorithm for intramodality MR brain images of different subjects using wavelet-based attribute vectors (WAVs) defined on every image voxel. The attribute vector (AV) is extracted from the wavelet subimages and reflects the image structure in a large neighborhood around the respective voxel in a multiscale fashion. It plays the role of a morphological signature for each voxel, and our goal is, therefore, to make it distinctive of the respective voxel. Correspondence is then determined from similarities of AVs. By incorporating the prior knowledge of the spatial relationship among voxels, the ability of the proposed algorithm to find anatomical correspondence is further improved. Experiments with MR images of human brains show that the algorithm performs similarly to experts, even for complex cortical structures. 相似文献