A multiscale non-orthogonal model for tensile properties of uncoated and coated F-12 aramid fabric

Coated F-12 aramid fabric can be used as the balloon envelopes material because of the high strength and light weight performance. In this paper, a multiscale non-orthogonal material model was established to capture the tensile properties of F-12 fabric with and without polyethylene terephthalate-aluminum (PET-Al) coating. Off-axial monotonic tensile tests were carried out to validate the material model. The nonlinearity and anisotropic properties of the coated and uncoated fabrics were investigated. In this model, the stress was obtained based on the equilibrium equations and yarn constitutive model in mesoscale. The mesoscale configuration was observed through optical microscope and SEM. The material orientation was aligned with the yarn directions and the stress was updated in real time. The material model was implemented by user material subroutine in ABAQUS and simulate fabric off-axial tensile test. In addition, a theory model to calculate the elastic property of the fabric was also set up using the mesoscale deformation mechanism. The simulation results were compared with the test and theory results. Results suggest that simulation results were agree well with test results. The fabrics were nearly linearity in weft direction, while the stressstrain curve exhibited obvious nonlinearity in warp direction. The tensile modulus of the fabric showed orthotropic behaviour rather than the strength. The coating can affect the strength and failure model of F-12 fabric. Yarn slip was the mostly failure model in uncoated fabric while break in coated fabric. Research in this study provides certain reference in analysis and design for balloon envelops

Development and Validation of an Effective CRISPR/Cas9 Vector for Efficiently Isolating Positive Transformants and Transgene-Free Mutants in a Wide Range of Plant Species

The CRISPR/Cas9 technique is a highly valuable tool in creating new materials for both basic and applied researches. Previously, we succeeded in effectively generating mutations in Brassica napus using an available CRISPR/Cas9 vector pKSE401, while isolation of Cas9-free mutants is laborious and inefficient. Here, we inserted a fluorescence tag (sGFP) driven by the constitutive 35S promoter into pKSE401 to facilitate a visual screen of mutants. This modified vector was named pKSE401G and tested in several dicot plant species, including Arabidopsis, B. napus, Fragaria vesca (strawberry), and Glycine max (soybean). Consequently, GFP-positive plants were readily identified through fluorescence screening in all of these species. Among these GFP-positive plants, the average mutation frequency ranged from 20.4 to 52.5% in Arabidopsis and B. napus with stable transformation, and was 90.0% in strawberry and 75.0% in soybean with transient transformation, indicating that the editing efficiency resembles that of the original vector. Moreover, transgene-free mutants were sufficiently identified in Arabidopsis in the T2 generation and B. napus in the T1 generation based on the absence of GFP fluorescence, and these mutants were stably transmissible to next generation without newly induced mutations. Collectively, pKSE401G provides us an effective tool to readily identify positive primary transformants and transgene-free mutants in later generations in a wide range of dicot plant species

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

A multiscale non-orthogonal model for tensile properties of uncoated and coated F-12 aramid fabric

Coated F-12 aramid fabric can be used as the balloon envelopes material because of the high strength and light weight performance. In this paper, a multiscale non-orthogonal material model was established to capture the tensile properties of F-12 fabric with and without polyethylene terephthalate-aluminum (PET-Al) coating. Off-axial monotonic tensile tests were carried out to validate the material model. The nonlinearity and anisotropic properties of the coated and uncoated fabrics were investigated. In this model, the stress was obtained based on the equilibrium equations and yarn constitutive model in mesoscale. The mesoscale configuration was observed through optical microscope and SEM. The material orientation was aligned with the yarn directions and the stress was updated in real time. The material model was implemented by user material subroutine in ABAQUS and simulate fabric off-axial tensile test. In addition, a theory model to calculate the elastic property of the fabric was also set up using the mesoscale deformation mechanism. The simulation results were compared with the test and theory results. Results suggest that simulation results were agree well with test results. The fabrics were nearly linearity in weft direction, while the stressstrain curve exhibited obvious nonlinearity in warp direction. The tensile modulus of the fabric showed orthotropic behaviour rather than the strength. The coating can affect the strength and failure model of F-12 fabric. Yarn slip was the mostly failure model in uncoated fabric while break in coated fabric. Research in this study provides certain reference in analysis and design for balloon envelops

Catalpol Induces Neuroprotection and Prevents Memory Dysfunction through the Cholinergic System and BDNF

To investigate the role and mechanism of catalpol on neuroprotective effects and memory enhancing effects simultaneously, neuroprotective effects of catalpol were assessed by neurological deficits score, TTC staining, and cerebral blood flow detecting. Morris water maze was employed to investigate its effects on learning and memory and then clarify its possible mechanisms relating the central cholinergic system and BDNF. Edaravone and oxiracetam were used for positive control drugs based on its different action. Results showed that catalpol and edaravone significantly facilitated neurological function recovery, reduced infarction volume, and increased cerebral blood flow in stroke mice. Catalpol and oxiracetam decreased the escape latency significantly and increased the numbers of crossing platform obviously. The levels of ACh, ChAT, and BDNF in catalpol group were increased in a dose-dependent manner, and AChE declined with a U-shaped dose-response curve. Moreover, the levels of muscarinic AChR subtypes M1 and M2 in hippocampus were considerably raised by catalpol. These results demonstrated that catalpol may be useful for neuroprotection and memory enhancement, and the mechanism may be related to the central cholinergic system

Three new species of Pinelema from caves in Guangxi, China (Araneae, Telemidae)

Three new Pinelema species, P. cunfengensis Zhao & Li, sp. n. (♂♀), P. podiensis Zhao & Li, sp. n. (♂♀), and P. qingfengensis Zhao & Li, sp. n. (♂♀), are described from the Guangxi Zhuang Autonomous Region of China, bringing the total number of Pinelema species to eight. All occur in Yunnan Province or the Guangxi Zhuang Autonomous Region. The male palp of Telemidae was studied for the first time using scanning electron microscope