1,171 research outputs found
The Universal Property of the Entropy Sum of Black Holes in All Dimensions
It is proposed by Cvetic et al [Phys. Rev. Lett. 106 (2011) 121301] that the
product of all horizon areas for general rotating multi-change black holes has
universal expressions independent of the mass. When we consider the product of
all horizon entropies, however, the mass will be present in some cases, while
another new universal property [JHEP 1401 (2014) 031] is preserved, which is
more general and says that the sum of all horizon entropies depends only on the
coupling constants of the theory and the topology of the black hole. The
property has been studied in limited dimensions and the generalization in
arbitrary dimensions is not straight-forward. In this Letter, we prove a useful
formula, which makes it possible to investigate this conjectured universality
in arbitrary dimensions for the maximally symmetric black holes in general
Lovelock gravity and gravity. We also propose an approach to compute the
entropy sum of general Kerr-(anti-)de-Sitter black holes in arbitrary
dimensions. In all these cases, we prove that the entropy sum only depends on
the coupling constants and the topology of the black hole.Comment: 16 pages,no figures;v2: 17 pages, references added, minor
corrections/modifications; v3: 16 pages, added references, correct some
expressons, added equation (16) to make the context more clear, to appear in
PL
VMT-Adapter: Parameter-Efficient Transfer Learning for Multi-Task Dense Scene Understanding
Large-scale pre-trained models have achieved remarkable success in various
computer vision tasks. A standard approach to leverage these models is to
fine-tune all model parameters for downstream tasks, which poses challenges in
terms of computational and storage costs. Recently, inspired by Natural
Language Processing (NLP), parameter-efficient transfer learning has been
successfully applied to vision tasks. However, most existing techniques
primarily focus on single-task adaptation, and despite limited research on
multi-task adaptation, these methods often exhibit suboptimal training and
inference efficiency. In this paper, we first propose an once-for-all Vision
Multi-Task Adapter (VMT-Adapter), which strikes approximately O(1) training and
inference efficiency w.r.t task number. Concretely, VMT-Adapter shares the
knowledge from multiple tasks to enhance cross-task interaction while preserves
task-specific knowledge via independent knowledge extraction modules. Notably,
since task-specific modules require few parameters, VMT-Adapter can handle an
arbitrary number of tasks with a negligible increase of trainable parameters.
We also propose VMT-Adapter-Lite, which further reduces the trainable
parameters by learning shared parameters between down- and up-projections.
Extensive experiments on four dense scene understanding tasks demonstrate the
superiority of VMT-Adapter(-Lite), achieving a 3.96%(1.34%) relative
improvement compared to single-task full fine-tuning, while utilizing merely
~1% (0.36%) trainable parameters of the pre-trained model.Comment: Accepted to AAAI202
2-Methylsulfanyl-4-(3-pyridyl)pyrimidine
In the title compound, C10H9N3S, the dihedral angle between the aromatic rings is 8.09 (14)°. In the crystal, a C—H⋯N interaction links the molecules, forming chains
Research into the impact of an imbalanced teaching-academic research evaluation system on the quality of higher education: based on the mediation effect of the sense of belonging to a university
University faculties are duty-bound to shoulder the functions of both teaching and doing scientific research, but they have been repeatedly criticized for emphasizing research over teaching. The current study analyzes the imbalance between teaching and scientific research in faculty evaluation system from three aspects through both quality study and quantity study: the evaluation subject, the weights difference in promotion, and the prediction of salary. Based on that, the influential effects of unbalanced evaluation system on long-term development of education has been explored. The current study also puts forward the moderating effect of the sense of belonging to colleges and universities. The result shows organizational belonging can significantly weaken the negative effects of the unbalanced evaluation system on education. Based on this, this paper makes further suggestions on the construction of university faculties’ evaluation system and the promotion of their sense of belonging
PPR proteins in plants: roles, mechanisms, and prospects for rice research
Pentatricopeptide repeat (PPR) proteins constitute one of the largest protein families in land plants, with over 300 members in various species. Nearly all PPR proteins are nuclear-encoded and targeted to the chloroplast and mitochondria, modulating organellar gene expression by participating in RNA metabolism, including mRNA stability, RNA editing, RNA splicing, and translation initiation. Organelle RNA metabolism significantly influences chloroplast and mitochondria functions, impacting plant photosynthesis, respiration, and environmental responses. Over the past decades, PPR proteins have emerged as a research focus in molecular biology due to their diverse roles throughout plant life. This review summarizes recent progress in understanding the roles and molecular mechanisms of PPR proteins, emphasizing their functions in fertility, abiotic and biotic stress, grain quality, and chloroplast development in rice. Furthermore, we discuss prospects for PPR family research in rice, aiming to provide a theoretical foundation for future investigations and applications
Realization of multiple topological states and topological phase transitions in (4,0) carbon nanotube derivatives
Exploring various topological states (TS) and topological phase transitions
(TPT) has attracted great attention in condensed matter physics. However, so
far, there is rarely a typical material system that can be used as a platform
to study the TS and TPT as the system transforms from one-dimensional (1D)
nanoribbons to two-dimensional (2D) sheet then to three-dimensional (3D) bulk.
Here, we first propose that some typical TS in 1D, 2D, and 3D systems can be
realized in a tight-binding (TB) model. Following the TB model and further
based on first-principles electronic structure calculations, we demonstrate
that the structurally stable (4,0) carbon nanotube derivatives are an ideal
platform to explore the semiconductor/nodal-point semimetal states in 1D
nanoribbons [1D-(4,0)-C16H4 and 1D-(4,0)-C32H4], nodal-ring semimetal state in
2D sheet [2D-(4,0)-C16], and nodal-cage semimetal state in 3D bulk
[3D-(4,0)-C16]. Furthermore, we calculate the characteristic band structures
and the edge/surface states of 2D-(4,0)-C16 and 3D-(4,0)-C16 to confirm their
nontrivial topological properties. Our work not only provides new excellent 2D
and 3D members for the topological carbon material family, but also serves as
an ideal template for the study of TS and TPT with the change of system
dimension.Comment: 17 pages, 7 figure
Valine induces inflammation and enhanced adipogenesis in lean mice by multi-omics analysis
IntroductionThe branched-chain amino acids (BCAAs) are essential to mammalian growth and development but aberrantly elevated in obesity and diabetes. Each BCAA has an independent and specific physio-biochemical effect on the host. However, the exact molecular mechanism of the detrimental effect of valine on metabolic health remains largely unknown.Methods and resultsThis study showed that for lean mice treated with valine, the hepatic lipid metabolism and adipogenesis were enhanced, and the villus height and crypt depth of the ileum were significantly increased. Transcriptome profiling on white and brown adipose tissues revealed that valine disturbed multiple signaling pathways (e.g., inflammation and fatty acid metabolism). Integrative cecal metagenome and metabolome analyses found that abundances of Bacteroidetes decreased, but Proteobacteria and Helicobacter increased, respectively; and 87 differential metabolites were enriched in several molecular pathways (e.g., inflammation and lipid and bile acid metabolism). Furthermore, abundances of two metabolites (stercobilin and 3-IAA), proteins (AMPK/pAMPK and SCD1), and inflammation and adipogenesis-related genes were validated.DiscussionValine treatment affects the intestinal microbiota and metabolite compositions, induces gut inflammation, and aggravates hepatic lipid deposition and adipogenesis. Our findings provide novel insights into and resources for further exploring the molecular mechanism and biological function of valine on lipid metabolism
Plasma Lipoprotein-associated Phospholipase A2 in Patients with Metabolic Syndrome and Carotid Atherosclerosis
<p>Abstract</p> <p>Background</p> <p>Lipoprotein-associated phospholipase A<sub>2 </sub>(Lp-PLA<sub>2</sub>) is a recently identified and potentially useful plasma biomarker for cardiovascular and atherosclerotic diseases. However, the correlation between the Lp-PLA<sub>2 </sub>activity and carotid atherosclerosis remains poorly investigated in patients with metabolic syndrome (MetS). The present study aimed to evaluate the potential role of Lp-PLA<sub>2 </sub>as a comprehensive marker of metabolic syndrome in individuals with and without carotid atherosclerosis.</p> <p>Methods</p> <p>We documented 118 consecutive patients with MetS and 70 age- and sex-matched healthy subjects served as controls. The patients were further divided into two groups: 39 with carotid plaques and 79 without carotid plaques to elucidate the influence of Lp-PLA<sub>2 </sub>on carotid atherosclerosis. The plasma Lp-PLA<sub>2 </sub>activity was measured by using ELISA method and carotid intimal-media thickness (IMT) was performed by ultrasound in all participants.</p> <p>Results</p> <p>Lp-PLA<sub>2 </sub>activity was significantly increased in MetS subgroups when compared with controls, and was higher in patients with carotid plaques than those without plaques (<it>P </it>< 0.05). Furthermore, we found that significant difference in Lp-PLA<sub>2 </sub>was obtained between patients with three and four disorders of metabolic syndrome (<it>P </it>< 0.01). Age (β = 0.183, <it>P </it>= 0.029), LDL-cholesterol (β = 0.401, <it>P </it>= 0.000) and waist-hip ratio (β = 0.410, <it>P </it>= 0.000) emerged as significant and independent determinants of Lp-PLA<sub>2 </sub>activity. Multiple stepwise regression analysis revealed that LDL-cholesterol (β = 0.309, <it>P </it>= 0.000), systolic blood pressure (β = 0.322, <it>P </it>= 0.002) and age (β = 0.235, <it>P </it>= 0.007) significantly correlated with max IMT, and Lp-PLA<sub>2 </sub>was not an independent predictor for carotid IMT.</p> <p>Conclusions</p> <p>Lp-PLA<sub>2 </sub>may be a modulating factor for carotid IMT via age and LDL-cholesterol, not independent predictor in the pathophysiological process of carotid atherosclerosis in patients with MetS.</p
Treatment and observation of postvitrectomy diabetic vitreous haemorrhage in patients with PDR
AIM: To discuss the treatment and to evaluate the therapeutic effect by reviewing a group of postvitrectomy diabetic vitreous haemorrhage(PDVH)cases after vitrectomy for proliferative diabetic retinopathy(PDR). METHODS: Retrospective analysis of 12 cases of 12 PDR patients with PDVH in our hospital from September 2015 to June 2017. First, conservative treatment was performed and then surgical treatments were performed on patients with large amount of bleeding and poor effect of conservative treatment(including anterior chamber flushing, vitreous lavage, vitrectomy, or combination of cataract surgery). The patients were observed and analyzed during and after surgeries. RESULTS: The mean duration between the first surgery and PDVH ranged from 1d to 10mo(mean 61.58±92.69d). The cases of early and late PDVH was 8 eyes and 4 eyes, respectively. Two eyes were treated with conservative treatment and the bleeding were absorbed after 2wk-1mo. Ten eyes without obvious improvement after treatment or intraocular pressure(IOP)increased again received surgical treatment, in which 2 eyes were treated with simple anterior chamber flushing, 8 eyes underwent vitreous lavage(2 eyes combined with cataract surgery, 1 eyes combined with silicone oil injection). Seven eyes received supplementary photocoagulation. Till the last follow-up, all vitreous haemorrhages resolved, and 9 eyes had better visual acuity. CONCLUSION: PDVH can be induced by various reasons and appropriate measures should be taken by regulating blood glucose, improving operative skills and timely symptomatic treatments to improve the visual acuity
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