41 research outputs found
Pentacarbonyl-1κ2 C,2κ3 C-(4-iodophenyl isocyanide-1κC)(μ-propane-1,3-dithiolato-1:2κ4 S,S′:S,S′)iron(I)(Fe—Fe)
In the title compound, [Fe2(C7H4IN)(C3H6S2)(CO)5], the Fe—Fe distance of 2.5156 (11) Å compares well with that in related model structures. The phenyl isocyanide ligand is in the basal position and trans to the S atoms of the propanedithiolate ligand due to steric hindrance. The crystal structure features C—H⋯O interactions
A knowledge graph empowered online learning framework for access control decision-making
Knowledge graph, as an extension of graph data structure, is being used in a wide range of areas as it can store interrelated data and reveal interlinked relationships between different objects within a large system. This paper proposes an algorithm to construct an access control knowledge graph from user and resource attributes. Furthermore, an online learning framework for access control decision-making is proposed based on the constructed knowledge graph. Within the framework, we extract topological features to represent high cardinality categorical user and resource attributes. Experimental results show that topological features extracted from knowledge graph can improve the access control performance in both offline learning and online learning scenarios with different degrees of class imbalance status
Auditor of State Mary Mosiman today released a reaudit report on the Mason City Community School District (District) for the period July 1, 2014 through June 30, 2015. The reaudit also covered items applicable to the years ended June 30, 2016 and June 30, 2017.
Auditor of State Mary Mosiman today released a reaudit report on the Mason City Community School District (District) for the period July 1, 2014 through June 30, 2015. The reaudit also covered items applicable to the years ended June 30, 2016 and June 30, 2017
Primer registro de anomalía intersexual gonadal de Trachurus mediterraneus (Steindachner, 1868) desde el Mar de Alborán.
El objetivo principal de este trabajo es dar a conocer el primer registro de una anomalía intersexual gonadal de Trachurus mediterraneus desde el mar de Alborán (Mediterráneo occidental). Este espécimen es el primer registro de intersexualidad para un jurel en
el mundo.Postprin
A Study of the Impact of COVID-19 on Urban Contact Networks in China Based on Population Flows
The emergence and enduring diffusion of COVID-19 has had a dramatic impact on cities worldwide. The scientific aim of this study was to introduce geospatial thinking to research related to infectious diseases, while the practical aim was to explore the impact on population movements and urban linkages in the longer term following a pandemic outbreak. Therefore, this study took 366 cities in China as the research subjects while exploring the relationship between urban contact and the outbreak of the pandemic from both national and regional perspectives using social network analysis (SNA), Pearson correlation analysis and multi-scale geographically weighted regression (MGWR) modeling. The results revealed that the number of COVID-19 infections in China fluctuated with strain variation over the study period; the urban contact network exhibited a significant trend of recovery. The pandemic had a hindering effect on national urban contact, and this effect weakened progressively. Meanwhile, the effect exhibited significant spatial heterogeneity, with a weakening effect in the eastern region ≈ northeast region > central region > western region, indicating a decreasing phenomenon from coastal to inland areas. Moreover, the four major economic regions in China featured border barrier effects, whereby urban contact networks constituted by cross-regional flows were more sensitive to the development of the pandemic. The geostatistical approach adopted in this study related to infectious disease and urban linkages can be used in other regions, and its findings provide a reference for China and other countries around the world to respond to major public health events
A Systemic Review and Meta-analysis of the Effect of SARS-CoV-2 Infection on Sperm Parameters
Objective. Several studies examined the putative effects of SARS-CoV-2 infection on sperm parameters. However, the results remain controversial. In this study, we conducted the most up-to-date systematic review and meta-analysis to investigate the effect of SARS-CoV-2 infection on sperm quality in COVID-19-positive and COVID-19-negative male participants. Method. Seven databases were searched for literature released through June 10, 2022, containing estimates for the outcomes of interest. Using a random-effects model (REM) or a fixed-effects model (FEM), we analyzed the pooled results. The quality of all included studies was assessed by the Newcastle-Ottawa scale. In addition, we performed a quantitative and subgroup analysis of semen data across all included studies. Results. Fourteen studies were extracted from 10 publications, involving a total of 1174 participates for meta-analysis. Sperm parameters of 521 COVID-19 male patients and 653 controls were analyzed. In 8 case-control studies, the pooled mean difference (MD) of total sperm motility was -5.37% (95% confidence interval (CI): -8.47 to -2.28; p<0.05), suggesting that total motility was significantly impaired in male COVID-19 cases. Subgroup analysis showed a significant decrease in semen volume, sperm concentration, and total motility in 238 patients with a recovery time of less than 90 days. Moreover, in the other 6 included pre- to post-COVID-19 studies, the pooled MDs of sperm concentration, total sperm count, total motility, progressive motility, and normal morphology were −6.54×106/ml (95% CI: -10.27 to -2.81; p<0.05), −38.89×106 (95% CI: -59.20 to -18.58; p<0.05), -7.21% (95% CI: -14.36 to -0.07; p<0.05), -5.12% (95% CI: -8.71 to -1.53; p<0.05), and -1.52% (95% CI: -2.88 to -0.16; p<0.05), respectively, which indicate SARS-CoV-2 infection significantly affected these five sperm parameters. Conclusion. Our results revealed that SARS-CoV-2 infection was significantly correlated with decreased sperm quality. Of six sperm parameters, total motility and sperm concentration were the most significantly decreased parameters. These results suggest a possible negative influence of SARS-CoV-2 infection on testicular function and male fertility. Given the potential detrimental effect of SARS-CoV-2 on semen quality, male reproductive health should be monitored closely in patients with COVID-19. This trial is registered with CRD42021275823
Green, Rapid, and Universal Preparation Approach of Graphene Quantum Dots under Ultraviolet Irradiation
It
is of great significance and importance to explore a mild, clean,
and highly efficient universal approach for the synthesis of graphene
quantum dots. Herein, we introduced a new green, rapid, and universal
preparation approach for graphene quantum dots via the free-radical
polymerization of oxygen-containing aromatic compounds under ultraviolet
irradiation. This approach had a high yield (86%), and the byproducts
are only H<sub>2</sub>O and CO<sub>2</sub>. The obtained graphene
quantum dots were well-crystallized and showed remarkable optical
and biological properties. The colorful, different-sized graphene
quantum dots can be used in fluorescent bioimaging in vitro and in
vivo. This approach is suitable not only for the preparation of graphene
quantum dots but also for heteroatom-doped graphene quantum dots
OsLG3 contributing to rice grain length and yield was mined by Ho-LAMap
Abstract Background Most agronomic traits in rice are complex and polygenic. The identification of quantitative trait loci (QTL) for grain length is an important objective of rice genetic research and breeding programs. Results Herein, we identified 99 QTL for grain length by GWAS based on approximately 10 million single nucleotide polymorphisms from 504 cultivated rice accessions (Oryza sativa L.), 13 of which were validated by four linkage populations and 92 were new loci for grain length. We scanned the Ho (observed heterozygosity per locus) index of coupled-parents of crosses mapping the same QTL, based on linkage and association mapping, and identified two new genes for grain length. We named this approach as Ho-LAMap. A simulation study of six known genes showed that Ho-LAMap could mine genes rapidly across a wide range of experimental variables using deep-sequencing data. We used Ho-LAMap to clone a new gene, OsLG3, as a positive regulator of grain length, which could improve rice yield without influencing grain quality. Sequencing of the promoter region in 283 rice accessions from a wide geographic range identified four haplotypes that seem to be associated with grain length. Further analysis showed that OsLG3 alleles in the indica and japonica evolved independently from distinct ancestors and low nucleotide diversity of OsLG3 in indica indicated artificial selection. Phylogenetic analysis showed that OsLG3 might have much potential value for improvement of grain length in japonica breeding. Conclusions The results demonstrated that Ho-LAMap is a potential approach for gene discovery and OsLG3 is a promising gene to be utilized in genomic assisted breeding for rice cultivar improvement