7,966 research outputs found

    Mutual correlation in the shock wave geometry

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    We probe the shock wave geometry with the mutual correlation in a spherically symmetric Reissner Nordstr\"om AdS black hole on the basis of the gauge/gravity duality. In the static background, we find that the regions living on the boundary of the AdS black holes are correlated provided the considered regions on the boundary are large enough. We also investigate the effect of the charge on the mutual correlation and find that the bigger the value of the charge is, the smaller the value of the mutual correlation will to be. As a small perturbation is added at the AdS boundary, the horizon shifts and a dynamical shock wave geometry forms after long time enough. In this dynamic background, we find that the greater the shift of the horizon is, the smaller the mutual correlation will to be. Especially for the case that the shift is large enough, the mutual correlation vanishes, which implies that the considered regions on the boundary are uncorrelated. The effect of the charge on the mutual correlation in this dynamic background is found to be the same as that in the static background.Comment: 10 page

    Sperm Nuclear Transfer and Transgenic Production in the Fish Medaka

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    Sperm nuclear transfer or intracytoplasmic sperm injection (ICSI) is a powerful assisted reproductive technology (ART) for treating human male infertility. Controversial reports of increased birth defects have raised concerns about the ART's safety. The cause for birth defects, however, has remained elusive for analysis in human because of the sample size, male infertility genetics, physiological heterogeneity and associated procedures such as embryo manipulations. Animal models are required to evaluate factors leading to the increased birth defects. Here we report the establishment of medakafish model for ICSI and transgenic production. This small laboratory fish has high fecundity and easy embryology. We show that ICSI produced a 5% high percentage of fertile animals that exhibited both paternal and maternal contribution as evidenced by the pigmentation marker. Furthermore, when sperm were pre-incubated with a plasmid ubiquitously expressing RFP and subjected to ICSI, 50% of sperm nuclear transplants showed germline transmission. We conclude that medaka is an excellent model for ICSI to evaluate birth defects and that sperm nuclear transfer can mediate stable gene transfer at high efficiency. Although more demanding for experimentation, sperm-mediated transgenesis should be particularly applicable for aquaculture species with a lengthy generation time and/or a large adult body size

    Impact of Sucrose Addition on the Physiochemical Properties and Volatile Compounds of “Shuangyou” Red Wines

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    “Shuangyou,” a Vitis amurensis Rupr. variety, is widely cultivated in northeastern and western China. Its berries have high acidity and low sugar content. In this study, different proportions of sucrose were added to the must samples during fermentation to investigate the effect of sugar on the physicochemical properties and volatile compounds of “Shuangyou” wines. The addition of sucrose significantly improved yeast growth and alcohol production, altered the color qualities, and slightly decreased titratable acidity during fermentation. The highest tested proportion of added sucrose resulted in the highest maximum yeast counts and final ethanol concentrations. Moreover, 37 volatile compounds (esters, alcohols, fatty acids, ketones, and aldehydes) were identified and quantified by solid-phase microextraction with gas chromatography-mass spectrometry. The concentrations of these compounds were correlated with the addition of sucrose. Furthermore, the addition of 100 g/L sucrose was sufficient for improving the concentrations of the aromatic compounds. The increase in ester, alcohol, and fatty acid concentration led to a positive OAVs impact (odor activity value > 1) at the end of fermentation

    Internal structure of hairy rotating black holes in three dimensions

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    We construct hairy rotating black hole solutions in three dimensional Einstein gravity coupled to a complex scalar field. When we turn on a real and uniform source on the dual CFT, the black hole is stationary with two Killing vectors and we show that there is no inner horizon for the black hole and the system evolves smoothly into a Kasner universe. When we turn on a complex and periodic driving source on the dual CFT with a phase velocity equal to the angular velocity of the black hole, we have a time-dependent black hole with only one Killing vector. We show that inside the black hole, after a rapid collapse of the Einstein-Rosen bridge, oscillations of the scalar field follow. Then the system evolves into the Kasner epoch with possible Kasner inversion, which occurs in most of the parameter regimes. In both cases, one of the metric fields obeys a simple relation between its value at the horizon and in the Kasner epoch.Comment: 35 pages, 14 figure

    PROTINFO: new algorithms for enhanced protein structure predictions

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    We describe new algorithms and modules for protein structure prediction available as part of the PROTINFO web server. The modules, comparative and de novo modelling, have significantly improved back-end algorithms that were rigorously evaluated at the sixth meeting on the Critical Assessment of Protein Structure Prediction methods. We were one of four server groups invited to make an oral presentation (only the best performing groups are asked to do so). These two modules allow a user to submit a protein sequence and return atomic coordinates representing the tertiary structure of that protein. The PROTINFO server is available at

    Early Functional and Cognitive Declines Measured by Auditory-Evoked Cortical Potentials in Mice With Alzheimer’s Disease

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    Alzheimer’s disease (AD) is characterized by a progressive loss of memory and cognitive decline. However, the assessment of AD-associated functional and cognitive changes is still a big challenge. Auditory-evoked cortical potential (AECP) is an event-related potential reflecting not only neural activation in the auditory cortex (AC) but also cognitive activity in the brain. In this study, we used the subdermal needle electrodes with the same electrode setting as the auditory brainstem response (ABR) recording and recorded AECP in normal aging CBA/CaJ mice and APP/PS1 AD mice. AECP in mice usually appeared as three positive peaks, i.e., P1, P2, and P3, and three corresponding negative peaks, i.e., N1, N2, and N3. In normal aging CBA mice, the early sensory peaks P1, N1, and P2 were reduced as age increased, whereas the later cognitive peaks N2, P3, and N3 were increased or had no changes with aging. Moreover, the latency of the P1 peak was increased as age increased, although the latencies of later peaks had a significant reduction with aging. In AD mice, peak P1 was significantly reduced in comparison with wild-type (WT) littermates at young ages, proceeding AD phenotype presentation. In particular, the later cognitive peak P3 was diminished after 3 months old, different from the normal aging effect. However, the latencies of AECP peaks in AD mice generally had no significant delay or changes with aging. Finally, consistent with AECP changes, the accumulation of amyloid precursor protein (APP) at the AC was visible in AD mice as early as 2 months old. These data suggest that AECP could serve as an early, non-invasive, and objective biomarker for detecting AD and AD-related dementia (ADRD)

    Sequencing and phylogenetic analysis of the wsp gene of Wolbachia in three geographic populations of an oak gall wasp, Andricus mairei (Hymenoptera: Cynipidae), from Hunan, South China

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    To understand the effects of Wolbachia in Andricus mairei Kieffer , an oak gall wasp ( Cynipini, Cynipidae) that forms clusters of up to 30 monothalamous galls in the catkins of Quercus glandulifera var. brevipetiolata Nakai, we examined the presence and infection frequency of Wolbachia in three widely separated geographic populations of A. mairei in Hunan Province, South China, using polymerase chain reaction and sequence determination of the wsp gene of Wolbachia from the three populations. Our survey results showed that Wolbachia infection rates were unusually high in the three test populations : 100% for the male wasps from all populations , while 100% , 100% and 80% for the Yueyang, Changsha and Shaoyang populations of the female wasps, respectively. The sequencing results showed that the gene from all the three populations is 561 bp in length. Comparison with the wsp gene sequences in A. mairei and Neuroterus macropterus , Biorhiza pallida , Andricus solitarius ( strain 1 ) and Synergus crassicornis revealed a 95% identity. The phylogenie relationship of Wolbachia strains in Cynipidae with the known wsp sequences indicated that the Wolbachia strain of A. mairei is closely related to that of N. macropterus , B. pallida, A. solitarius ( strain 1 ) , and S. crassicornis , and belongs to the A group. We also discovered strikingly male-biased sex ratios in all the test populations: females only accounted for 15.3%, 12. 1%, and 19. 8% of the Yueyang, Changsha, and Shaoyang populations, respectively, indicating the extremely male-biased sex ratios. These results suggest that the symbiosis of Wolbachia with A. mairei does not induce parthenogenesis in A. mairei, which can not be properly explained and is worth further investigation

    ProKD: An Unsupervised Prototypical Knowledge Distillation Network for Zero-Resource Cross-Lingual Named Entity Recognition

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    For named entity recognition (NER) in zero-resource languages, utilizing knowledge distillation methods to transfer language-independent knowledge from the rich-resource source languages to zero-resource languages is an effective means. Typically, these approaches adopt a teacher-student architecture, where the teacher network is trained in the source language, and the student network seeks to learn knowledge from the teacher network and is expected to perform well in the target language. Despite the impressive performance achieved by these methods, we argue that they have two limitations. Firstly, the teacher network fails to effectively learn language-independent knowledge shared across languages due to the differences in the feature distribution between the source and target languages. Secondly, the student network acquires all of its knowledge from the teacher network and ignores the learning of target language-specific knowledge. Undesirably, these limitations would hinder the model's performance in the target language. This paper proposes an unsupervised prototype knowledge distillation network (ProKD) to address these issues. Specifically, ProKD presents a contrastive learning-based prototype alignment method to achieve class feature alignment by adjusting the distance among prototypes in the source and target languages, boosting the teacher network's capacity to acquire language-independent knowledge. In addition, ProKD introduces a prototypical self-training method to learn the intrinsic structure of the language by retraining the student network on the target data using samples' distance information from prototypes, thereby enhancing the student network's ability to acquire language-specific knowledge. Extensive experiments on three benchmark cross-lingual NER datasets demonstrate the effectiveness of our approach.Comment: AAAI 202
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