175 research outputs found
Execution and authentication of function queries
We introduce a new query primitive called Function Query (FQ). An FQ operates on a set of math functions and retrieves the functions whose output with a given input satisfies a query condition (e.g., being among top-k, within a given range). While FQ finds its natural uses in querying a database of math functions, it can also be applied on a database of discrete values. We show that by interpreting the database as a set of user-defined functions, FQ can retrieve the information like existing analytic queries such as top-k query and scalar product query and even more. Our research addresses the challenges of FQ execution and authentication. The former is how to minimize the computation and storage costs in processing an FQ, whereas the latter, how to verify that the result of an FQ returned by a potentially untrustworthy server is indeed correct. Our solutions are inspired from the observations that 1) the intersections of a set of continuous functions partition their domain into a number of subdomains, and 2) in each of these subdomains, the functions can be sorted based on their output. We prove the correctness of the proposed techniques and evaluate their performance through analysis, prototyping, and experiments using both synthetic and real-world data. In all settings, our techniques exhibit excellent performance. In addition to FQ, our research has developed another query primitive called Improvement Query, which we also include in this dissertation
Algebraic fibre spaces with strictly nef relative anti-log canonical divisor
Let be a projective klt pair, and a fibration to a
smooth projective variety with strictly nef relative anti-log canonical
divisor . We prove that is a locally constant fibration
with rationally connected fibres, and the base is a canonically polarized
hyperbolic projective manifold. In particular, when is a single point, we
establish that is rationally connected. Moreover, when and
is strictly nef, we prove that is ample, which
confirms the singular version of a conjecture of Campana-Peternell for
threefolds.Comment: 24 page
Genomic evidence of adaptive evolution in the reptilian SOCS gene family
The suppressor of the cytokine signaling (SOCS) family of proteins play an essential role in inhibiting cytokine receptor signaling by regulating immune signal pathways. Although SOCS gene functions have been examined extensively, no comprehensive study has been performed on this gene family’s molecular evolution in reptiles. In this study, we identified eight canonical SOCS genes using recently-published reptilian genomes. We used phylogenetic analysis to determine that the SOCS genes had highly conserved evolutionary dynamics that we classified into two types. We identified positive SOCS4 selection signals in whole reptile lineages and SOCS2 selection signals in the crocodilian lineage. Selective pressure analyses using the branch model and Z-test revealed that these genes were under different negative selection pressures compared to reptile lineages. We also concluded that the nature of selection pressure varies across different reptile lineages on SOCS3, and the crocodilian lineage has experienced rapid evolution. Our results may provide a theoretical foundation for further analyses of reptilian SOCS genes’ functional and molecular mechanisms, as well as their roles in reptile growth and development
Comparative Metabolomics Revealed Metabolite Differences in Bamboo Shoots (Chimonobambusa tumidissinoda Hsueh & T. P. Yi ex Ohrnberger) at Different Growth Stages
In order to explore the dynamic changes and stage specificity of metabolites in bamboo shoots during its growth, widely targeted metabolomics based on ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was used to analyze fresh bamboo shoots harvested at heights of 10 and 25 cm. The results showed that a total of 875 metabolites belonging to 13 categories were identified from bamboo shoots, including sugars, alcohols and flavonoids, whose relative contents significantly increased in 25 cm-high bamboo shoots. Moreover, the results of multivariate statistical analyses showed that the metabolites in bamboo shoots had an obvious stage specificity. Totally 283 significantly differential metabolites were identified between the two growth stages, of which 102 metabolites were annotated to 82 metabolic pathways. The contents of 20 major nutrients did not significantly differ between the two growth stages; however, the contents of metabolites related to taste, flavor and bioactive function were higher, while the content of bitter compounds was lower in the 25 cm-high bamboo shoots. Therefore, compared with the 10 cm-high bamboo shoots, the 25 cm-high bamboo shoots have a higher comprehensive economic value and are more suitable for harvesting. The results of this study can provide a theoretical reference for the comprehensive development and sustainable utilization of Chimonobambusa tumidissinoda
Genome-wide identification of TCP transcription factors and their potential roles in hydrolyzable tannin production in Quercus variabilis cupule
Hydrolyzable tannins (HTs) have garnered significant attention due to their proven beneficial effects in the clinical treatment of various diseases. The cupule of Chinese cork oak (Quercus variabilis Blume) has been used as raw material of traditional medicine for centuries for its high content of HTs. Previous studies have identified UGT84A13 as a key enzyme in the HT biosynthesis pathway in Q. variabilis, but the transcriptional regulation network of UGT84A13 remains obscure. Here, we performed a comprehensive genome-wide identification of the TCP transcription factors in Q. variabilis, elucidating their molecular evolution and gene structure. Gene expression analysis showed that TCP3 from the CIN subfamily and TCP6 from the PCF subfamily were co-expressed with UGT84A13 in cupule. Further functional characterization using dual-luciferase assays confirmed that TCP3, rather than TCP6, played a role in the transcriptional regulation of UGT84A13, thus promoting HT biosynthesis in the cupule of Q. variabilis. Our work identified TCP family members in Q. variabilis for the first time, and provided novel insights into the transcriptional regulatory network of UGT84A13 and HT biosynthesis in Q. variabilis, explaining the reason why the cupule enriches HTs that could be used for traditional medicine
Current situation, bottlenecks, and path options for the development of capital flows and integration in the Yangtze River Delta region
IntroductionCapital plays a crucial role in the development of regional economies, especially in low-income regions where it acts as a primary driver of economic growth. Efficient capital flow is essential for optimizing resource allocation and facilitating the development of integrated capital markets. This passage introduces the topic of capital, capital flow, and capital market integration and highlights their significance in regional development.MethodsTo gain a comprehensive understanding of capital flow and integration in the Yangtze River Delta region, the researchers conducted a connotative analysis. They constructed indicators from various aspects, including social fixed asset investment, bank capital flow, government transfer payments, social financing structure, and foreign direct investment. By utilizing these indicators, the researchers aimed to assess the current situation and identify bottlenecks related to capital flow and integration. Additionally, they drew on experiences from foreign capital flow and integration development to enrich their analysis.ResultsThe analysis revealed several primary bottlenecks affecting capital flow and integration in the Yangtze River Delta region. These bottlenecks include an unsound banking management system, the presence of government competition and administrative barriers, and shortcomings within listed companies. The results highlight the specific challenges that hinder the smooth functioning and integration of capital in the region.DiscussionTo promote the development of capital flows and integration in the Yangtze River Delta region, the researchers propose various recommendations. These suggestions include promoting the development of listed companies, establishing a robust banking management model, improving relevant government policies, and optimizing the investment environment. These recommendations serve as important guidelines for policymakers to enhance capital flow and integration in the Yangtze River Delta city cluster. Furthermore, they emphasize the need to strengthen financial supervision and improve institutional mechanisms within the three provinces and one city comprising the region
Significance of research on natural products from marine-derived Aspergillus species as a source against pathogenic bacteria
Bacterial infections pose a significant clinical burden on global health. The growing incidence of drug-resistant pathogens highlights the critical necessity to identify and isolate bioactive compounds from marine resources. Marine-derived fungi could provide novel lead compounds against pathogenic bacteria. Due to the particularity of the marine environment, Aspergillus species derived from marine sources have proven to be potent producers of bioactive secondary metabolites and have played a considerable role in advancing drug development. This study reviews the structural diversity and activities against pathogenic bacteria of secondary metabolites isolated from marine-derived Aspergillus species over the past 14 years (January 2010–June 2024), and 337 natural products (including 145 new compounds) were described. The structures were divided into five major categories—terpenoids, nitrogen-containing compounds, polyketides, steroids, and other classes. These antimicrobial metabolites will offer lead compounds to the development and innovation of antimicrobial agents
Execution and authentication of function queries
We introduce a new query primitive called Function Query (FQ). An FQ operates on a set of math functions and retrieves the functions whose output with a given input satisfies a query condition (e.g., being among top-k, within a given range). While FQ finds its natural uses in querying a database of math functions, it can also be applied on a database of discrete values. We show that by interpreting the database as a set of user-defined functions, FQ can retrieve the information like existing analytic queries such as top-k query and scalar product query and even more. Our research addresses the challenges of FQ execution and authentication. The former is how to minimize the computation and storage costs in processing an FQ, whereas the latter, how to verify that the result of an FQ returned by a potentially untrustworthy server is indeed correct. Our solutions are inspired from the observations that 1) the intersections of a set of continuous functions partition their domain into a number of subdomains, and 2) in each of these subdomains, the functions can be sorted based on their output. We prove the correctness of the proposed techniques and evaluate their performance through analysis, prototyping, and experiments using both synthetic and real-world data. In all settings, our techniques exhibit excellent performance. In addition to FQ, our research has developed another query primitive called Improvement Query, which we also include in this dissertation.</p
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