Telomerase RNA TLC1 Shuttling to the Cytoplasm Requires mRNA Export Factors and Is Important for Telomere Maintenance

SummaryTelomerases protect the ends of linear chromosomes from shortening. They are composed of an RNA (TLC1 in S. cerevisiae) and several proteins. TLC1 undergoes several maturation steps before it is exported into the cytoplasm to recruit the Est proteins for complete assembly. The mature telomerase is subsequently reimported into the nucleus, where it fulfills its function on telomeres. Here, we show that TLC1 export into the cytoplasm requires not only the Ran GTPase-dependent karyopherin Crm1/Xpo1 but also the mRNA export machinery. mRNA export factor mutants accumulate mature and export-competent TLC1 RNAs in their nuclei. Moreover, TLC1 physically interacts with the mRNA transport factors Mex67 and Dbp5/Rat8. Most importantly, we show that the nuclear export of TLC1 is an essential step for the formation of the functional RNA containing enzyme, because blocking TLC1 export in the mex67-5 xpo1-1 double mutant prevents its cytoplasmic maturation and leads to telomere shortening

Analysis on Parameters of Regeneration Subsystem in Liquid Desiccant Dehumidification Systems

Along with the widely use in industries and lives, the dehumidification systems have consumed a large amount of energy. Fortunately, the application of liquid desiccant dehumidification system can greatly reduce the consumption of high-grade energies. To improve the advantages of liquid desiccant system compared with the conventional dehumidification system, one of the key measures is to increase the efficiency of the regeneration sub-system. In this study, models for the regeneration tower and counter-current heat exchanger, which are recognized by previous experiments, are employed and the corresponding VC++ computer program modules are used to describe the heat and mass transfer processes between the liquid desiccant solution and moist air in the regenerator and the heat transfer process in heat exchanger respectively. The orthogonal design is used to arrange the numerical experiment. The results are analyzed by the method of variance analysis to determine the relative significance of operating parameters and the interactions between them. The analysis on the influence factors shows that for the evaporation rate of water vapor in the regenerator, the important parameters are the inlet temperature and concentration of the solution, the mass flow ratio of dry air to dehydrated desiccant, and the NTU of the regenerator. For the regeneration efficiency, the mass flow ratio of dry air to dehydrated desiccant, the NTU of the regenerator and inlet temperature of solution are important parameters. There is no interaction that influences the evaporation rate of water vapor and the regeneration efficiency significantly

承德普陀宗乘之庙石质文物现状问题及对策

The Putuo Zongcheng Temple is the largest temple in the outer eight temples of “Chengde Mountain Resort and Outer Eight Temples”. It preserves a large number of stone cultural relics and has a high historical, artistic and scientific value. Under the influence of long-term natural environment and human production activities, these cultural stone relics have experienced climatic diseases to varying degrees, which seriously endanger the life of cultural relics and require maintenance and urgent protection. It is essential to conduct systematic and detailed disease investigation and analysis before repairing and protecting these stone artifacts.   In May 2007, July 2012 and August 2016, I went to the Putuo Zongcheng Temple in Chengde three times to investigate it. This document systematically analyzes the existing types of diseases and the causes of these diseases by investigating the current status of the preservation of stone artifacts in Putuo Zongcheng Temple. The main reasons are natural and environmental factors, and propose countermeasures to improve the status of stone cultural relics. The statistics of these diseases can provide an investigation and theoretical basis for the protection and restoration later.  El Templo Putuo Zongcheng es el templo más grande en los ocho templos exteriores de " Residencia de Montaña de Chengde y Ocho Templos Exteriores". Conserva una gran cantidad de reliquias culturales de piedra y tiene un alto valor histórico, artístico y científico. Bajo la influencia del medio ambiente natural a largo plazo y las actividades de producción humana, estas reliquias culturales de piedra han experimentado enfermedades climáticas en diversos grados, que ponen en peligro la vida de las reliquias culturales y requieren mantenimiento y protección urgente. Es esencial realizar una investigación y análisis sistemáticos y detallados de la enfermedad antes de reparar y proteger estos artefactos de piedra.   En mayo de 2007, julio de 2012 y agosto de 2016, fui al Templo Putuo Zongcheng en Chengde tres veces para investigar su estado de conservación. Este documento analiza sistemáticamente los tipos existentes de enfermedades y las causas de estas enfermedades al investigar el estado actual de la preservación de los artefactos de piedra en el Templo Putuo Zongcheng. Las razones principales son factores naturales y ambientales, y proponen contramedidas para mejorar el estado de las reliquias culturales de piedra. Las estadísticas de estas enfermedades pueden proporcionar una investigación y una base teórica para la protección y restauración posteriormente

Theoretical analysis of a membrane-based cross-flow liquid desiccant system

Liquid desiccant air dehumidification has become one of the most widely used dehumidification technologies with advantages of high efficiency, no liquid condensate droplets and capability of energy storage. In this paper a cross-flow mathematical model is developed for a single layer membrane unit. The governing equations are solved iteratively by finite difference method. The performance analysis is carried out for a small-scale membrane-based dehumidification module consisting of 8 air channels and 8 solution channels. The influences of main design parameters on system effectiveness are evaluated. These include air flow rate (NTU), solution to air mass flow rate ration (m*) and solution inlet temperature and concentration. It is revealed that higher sensible and latent effectiveness can be achieved with larger NTU and m*. Increasing solution concentration can also improve the dehumidification effect

Chiral metallo-supramolecular complexes selectively recognize human telomeric G-quadruplex DNA

Here, we report the first example that one enantiomer of a supramolecular cylinder can selectively stabilize human telomeric G-quadruplex DNA. The P-enantiomer of this cylinder has a strong preference for G-quadruplex over duplex DNA and, in the presence of sodium, can convert G-quadruplexes from an antiparallel to a hybrid structure. The compound's chiral selectivity and its ability to discriminate quadruplex DNA have been studied by DNA melting, circular dichroism, gel electrophoresis, fluorescence spectroscopy and S1 nuclease cleavage. The chiral supramolecular complex has both small molecular chemical features and the large size of a zinc-finger-like DNA-binding motif. The complex is also convenient to synthesize and separate enantiomers. These results provide new insights into the development of chiral anticancer agents for targeting G-quadruplex DNA

Theoretical analysis of a membrane-based cross-flow liquid desiccant system

Liquid desiccant air dehumidification has become one of the most widely used dehumidification technologies with advantages of high efficiency, no liquid condensate droplets and capability of energy storage. In this paper a cross-flow mathematical model is developed for a single layer membrane unit. The governing equations are solved iteratively by finite difference method. The performance analysis is carried out for a small-scale membrane-based dehumidification module consisting of 8 air channels and 8 solution channels. The influences of main design parameters on system effectiveness are evaluated. These include air flow rate (NTU), solution to air mass flow rate ration (m*) and solution inlet temperature and concentration. It is revealed that higher sensible and latent effectiveness can be achieved with larger NTU and m*. Increasing solution concentration can also improve the dehumidification effect

MiR-384 is associated with renal damage in lupus nephritis via regulation of TET3 expression

Purpose: To investigate the correlations between miR-384 expression and renal damage in lupus nephritis (LN).Methods: Lupus nephritis and normal tissues were collected during surgery. The relative miR-384 expression was evaluated by extracting RNA and performing quantitative real time PCR (qRT-PCR) assays. Expression of ten-eleven translocation (TET3) mRNA and protein were measured by qRT-PCR and western blotting, respectively. The 24-h urine protein, serum complement C3, and serum creatinine were determined using commercial enzyme-linked immunosorbent assay (ELISA) kits. TargetScan and luciferase assays were used to validate the binding site for miR-384 and its target mRNA. Relationships among miR-384, TET3, and renal damage were analyzed by Spearman rank-order correlation coefficients.Results: MiR-384 expression increased in LN tissues and was positively correlated with the activity index (AI) and chronicity index of LN, whereas miR-384 expression and serum complement C3 were negatively correlated. Positive correlations were observed between miR-384 expression and 24-h urine protein, serum creatinine, and systemic lupus erythematosus disease AI. TargetScan and luciferaseassays indicated that the TET3 3′-UTR was the direct target of miR-384. MiR-384 upregulation inhibited TET3 mRNA and protein  expression, and was negatively associated with renal damage in LN.Conclusion: MiR-384 upregulation contributes to renal damage in LN by targeting the 3′-UTR of TET3 mRNA, suggesting that miR-384 is a potential biomarker and therapeutic target in LN. Keywords: MiR-384, Renal damage, Lupus nephritis, Ten-eleven translocation, TET

Preparation and properties of antistatic high-strength aramid III/MWCNTs-OH fibers

Composite fibers made from aramid III and hydroxylated multiwalled carbon nanotubes (MWCNTs-OH) combine the excellent mechanical and electrical properties of both components, resulting in strong antistatic performance. However, it is of paramount importance to ensure the homogeneous dispersion of multi-walled carbon nanotubes functionalized with hydroxyl groups (MWCNTs-OH) within the aramid III spinning solution and optimize the compatibility between the two constituents to augment the overall performance of the composite fibers. To this end, this investigation successfully accomplished the dispersion of MWCNTs-OH in the spinning solution and probed the dispersion mechanism using molecular dynamics simulations. Moreover, composite fibers, comprising 2.4 weight percent MWCNTs-OH, were initially fabricated using the wet spinning method. These fibers displayed a uniform texture and a tensile strength of 1.210 GPa, signifying a noteworthy enhancement of 113.25% in comparison to the strength prior to modification. With respect to thermal behavior, the fibers exhibited a mass reduction of 21.24% within the temperature range of 0°C–538°C. In the temperature interval from 538°C to 800°C, the mass loss diminished to 10.31%, representing a substantial 71.03% reduction when compared to the unmodified state. Remarkably, even when subjected to temperatures exceeding 800°C, the composite fibers retained a residual mass of 68.45%, indicating a notable 61.17% increase from their initial condition. In terms of electrical properties, the fibers exhibited a specific resistance (ρ) of 3.330 × 109 Ω cm, demonstrating effective antistatic behavior. In summary, the antistatic composite fibers studied in this paper can effectively mitigate the hazards of static electricity in various applications, including military protection and engineering equipment in both military and civilian fields