Locomotion analysis and optimization of actinomorphic robots with soft arms actuated by shape memory alloy wires

This article presents the locomotion analysis and optimization of actinomorphic soft robots, which are composed of soft arms actuated by shape memory alloy wires. The soft arm that is a composite modular structure is actuated by a self-sensing feedback control strategy. A theoretical model was established to describe the deformation of the soft arm, combining the Euler-Bernoulli beam model of the soft arm with the constitutive model and the heat transfer model of the shape memory alloy wire. The kinematics of the actinomorphic soft robot was analyzed using the modified Denavit-Hartenberg method, and the motion equation of the actinomorphic soft robot was presented based on the quasi-static hypothesis. Results show that the actinomorphic soft robot moves with a zig-zag pattern. The locomotion of four actinomorphic soft robots with three to six arms was analyzed, and the gait parameters of each locomotion type were optimized. The optimization results indicate that the three-arm actinomorphic robot with certain gait parameters has the best performance and achieves a maximum stride length of 75 mm. A series of experiments were conducted to investigate the movement performance of the three-arm actinomorphic robot in various environments

Identification of a novel MYC target gene set signature for predicting the prognosis of osteosarcoma patients

Osteosarcoma is a primary malignant tumor found mainly in teenagers and young adults. Patients have very little long-term survival. MYC controls tumor initiation and progression by regulating the expression of its target genes; thus, constructing a risk signature of osteosarcoma MYC target gene set will benefit the evaluation of both treatment and prognosis. In this paper, we used GEO data to download the ChIP-seq data of MYC to obtain the MYC target gene. Then, a risk signature consisting of 10 MYC target genes was developed using Cox regression analysis. The signature indicates that patients in the high-risk group performed poorly. After that, we verified it in the GSE21257 dataset. In addition, the difference in tumor immune function among the low- and high-risk populations was compared by single sample gene enrichment analysis. Immunotherapy and prediction of response to the anticancer drug have shown that the risk signature of the MYC target gene set was positively correlated with immune checkpoint response and drug sensitivity. Functional analysis has demonstrated that these genes are enriched in malignant tumors. Finally, STX10 was selected for functional experimentation. STX10 silence has limited osteosarcoma cell migration, invasion, and proliferation. Therefore, these findings indicated that the MYC target gene set risk signature could be used as a potential therapeutic target and prognostic indicator in patients with osteosarcoma

Mining the candidate genes of rice panicle traits via a genome-wide association study

Panicle traits are important for improving the panicle architecture and grain yield of rice. Therefore, we performed a genome-wide association study (GWAS) to analyze and determine the genetic determinants of five panicle traits. A total of 1.29 million single nucleotide polymorphism (SNP) loci were detected in 162 rice materials. We carried out a GWAS of panicle length (PL), total grain number per panicle (TGP), filled grain number per panicle (FGP), seed setting rate (SSR) and grain weight per panicle (GWP) in 2019, 2020 and 2021. Four quantitative trait loci (QTLs) for PL were detected on chromosomes 1, 6, and 9; one QTL for TGP, FGP, and GWP was detected on chromosome 4; two QTLs for FGP were detected on chromosomes 4 and 7; and one QTL for SSR was detected on chromosome 1. These QTLs were detected via a general linear model (GLM) and mixed linear model (MLM) in both years of the study period. In this study, the genomic best linear unbiased prediction (BLUP) method was used to verify the accuracy of the GWAS results. There are nine QTLs were both detected by the multi-environment GWAS method and the BLUP method. Moreover, further analysis revealed that three candidate genes, LOC_Os01g43700, LOC_Os09g25784, and LOC_Os04g47890, may be significantly related to panicle traits of rice. Haplotype analysis indicated that LOC_Os01g43700 and LOC_Os09g25784 are highly associated with PL and that LOC_Os04g47890 is highly associated with TGP, FGP, and GWP. Our results offer essential genetic information for the molecular improvement of panicle traits. The identified candidate genes and elite haplotypes could be used in marker-assisted selection to improve rice yield through pyramid breeding

Chemiluminescence determination of surfactant Triton X-100 in environmental water with luminol-hydrogen peroxide system

<p>Abstract</p> <p>Background</p> <p>The rapid, simple determination of surfactants in environmental samples is essential because of the extensive use and its potential as contaminants. We describe a simple, rapid chemiluminescence method for the direct determination of the non-ionic surfactant Triton X-100 (polyethylene glycol tert-octylphenyl ether) in environmental water samples. The optimized experimental conditions were selected, and the mechanism of the Luminol-H₂O₂-Triton X-100 chemiluminesence system was also studied.</p> <p>Results</p> <p>The novel chemiluminescence method for the determination of non-ionic surfactant Triton X-100 was based on the phenomenon that Triton X-100 greatly enhanced the CL signal of the luminol-H₂O₂system. The alkaline medium of luminol and the pH value obviously affected the results. Luminol concentration and hydrogen peroxide concentration also affected the results. The optimal conditions were: Na₂CO₃being the medium, pH value 12.5, luminol concentration 1.0 × 10^-4mol L^-1, H₂O₂concentration 0.4 mol L^-1. The possible mechanism was studied and proposed.</p> <p>Conclusion</p> <p>Under the optimal conditions, the standard curve was drawn up and quotas were evaluated. The linear range was 2 × 10^-4g·mL^-1-4 × 10^-2g·mL^-1(w/v), and the detection limit was 3.97 × 10^-5g·mL^-1Triton X-100 (w/v). The relative standard deviation was less than 4.73% for 2 × 10^-2g·mL^-1(w/v) Triton X-100 (n = 7). This method has been applied to the determination of Triton X-100 in environmental water samples. The desirable recovery ratio was between 96%–102% and the relative standard deviation was 2.5%–3.3%. The luminescence mechanism was also discussed in detail based on the fluorescence spectrum and the kinetic curve, and demonstrated that Triton X-100-luminol-H₂O₂was a rapid reaction.</p

Vehicle Routing Problem with Uncertain Demands: An Advanced Particle Swarm Algorithm

The Vehicle Routing Problem (VRP) has been thoroughly studied in the last decades. However, the main focus has been on the deterministic version where customer demands are fixed and known in advance. Uncertainty in demand has not received enough consideration. When demands are uncertain, several problems arise in the VRP. For example, there might be unmet customers¿ demands, which eventually lead to profit loss. A reliable plan and set of routes, after solving the VRP, can significantly reduce the unmet demand costs, helping in obtaining customer satisfaction. This paper investigates a variant of an uncertain VRP in which the customers¿ demands are supposed to be uncertain with unknown distributions. An advanced Particle Swarm Optimization (PSO) algorithm has been proposed to solve such a VRP. A novel decoding scheme has also been developed to increase the PSO efficiency. Comprehensive computational experiments, along with comparisons with other existing algorithms, have been provided to validate the proposed algorithms.Moghaddam, BF.; Ruiz García, R.; Sadjadic, SJ. (2012). Vehicle Routing Problem with Uncertain Demands: An Advanced Particle Swarm Algorithm. Computers and Industrial Engineering. 62(1):306-317. doi:10.1016/j.cie.2011.10.001S30631762

Small but Heavy Role: MicroRNAs in Hepatocellular Carcinoma Progression

Hepatocellular carcinoma (HCC), which accounts for 85–90% of primary liver cancer, is the fifth most common malignant tumor and the third leading cause of cancer-related deaths worldwide, but the pathological mechanism of HCC is still not fully elucidated. miRNAs are evolutionarily endogenous small noncoding RNAs that negatively regulate gene expression via posttranscriptional inhibition or target mRNA degradation in several diseases, especially human cancer. Therefore, discovering the roles of miRNAs is appealing to scientific researchers. Emerging evidence has shown that the aberrant expressions of numerous miRNAs are involved in many HCC biological processes. In hepatocarcinogenesis, miRNAs with dysregulated expression can exert their function as oncogenes or tumor suppressors depending on their cellular target during the cell cycle, and in tumor development, differentiation, apoptosis, angiogenesis, metastasis, and progression of the tumor microenvironment. In this review, we summarize current findings on miRNAs and assess their functions to explore the molecular mechanisms of tumor progression in HCC

Hereditary Nonpolyposis Colorectal Cancer and Cancer Syndromes: Recent Basic and Clinical Discoveries

Approximately one-third of individuals diagnosed with colorectal cancer have a family history of cancer, suggesting that CRCs may result from a heritable component. Despite the availability of current gene-identification techniques, only 5% of all CRCs emerge from well-identifiable inherited causes for predisposition, including polyposis and nonpolyposis syndromes. Hereditary nonpolyposis colorectal cancer represents a large proportion of cases, and robustly affected patients are at increased risk for early onset, synchronous, and metachronous colorectal malignancies and extracolonic malignancies. HNPCC encompasses several cancer syndromes, such as Lynch syndrome, Lynch-like syndrome, and familial colorectal cancer type X, which have remarkable clinical presentations and overlapping genetic profiles that make clinical diagnosis a challenging task. Therefore, distinguishing between the HNPCC disorders is crucial for physicians as an approach to tailor different recommendations for patients and their at-risk family members according to the risks for colonic and extracolonic cancer associated with each syndrome. Identification of these potential patients through epidemiological characteristics and new genetic testing can estimate the individual risk, which informs appropriate cancer screening, surveillance, and/or treatment strategies. In the past three years, many appealing and important advances have been made in our understanding of the relationship between HNPCC and CRC-associated syndromes. The knowledge from the genetic profile of cancer syndromes and unique genotype-phenotype profiles in the different syndromes has changed our cognition. Therefore, this review presents and discusses HNPCC and several common nonpolyposis syndromes with respect to molecular phenotype, histopathologic features, and clinical presentation

Tunable smart digital structure (SDS) to modularly assemble soft actuators with layered adhesive bonding

Many shape memory alloy (SMA)-based soft actuators have specific composite structures and manufacture processes, and are therefore unique. However, these exclusive characteristics limit their capabilities and applications, so in this article a soft and smart digital structure (SDS) is proposed that acts like a modular unit to assemble soft actuators by a layered adhesive bonding process. The SDS is a fully soft structure that encapsulates a digital skeleton consisting of four groups of parallel and independently actuated SMA wires capable of outputting a four-channel tunable force. The layered adhesive bonding process modularly bonds several SDSs with an elastic backbone to fabricate a layered soft actuator where the elastic backbone is used to recover the SDSs in a cooling process using the SMA wires. Two kinds of SDS-based soft actuators were modularly assembled, an actuator, SDS-I, with a two-dimensional reciprocal motion, and an actuator, SDS-II, capable of bi-directional reciprocal motion. The thermodynamics and phase transformation modeling of the SDS-based actuator were analyzed. Several extensional soft actuators were also assembled by bonding the SDS with an anomalous elastic backbone or modularly assembling the SDS-Is and SDS-IIs. These modularly assembled soft actuators delivered more output channels and a complicated motion, e.g., an actinomorphic soft actuator with four SDS-Is jumps in a series of hierarchical heights and directional movement by tuning the input channels of the SDSs. This result showed that the SDS can modularly assemble multifarious soft actuators with diverse capabilities, steerability and tunable outputs

Behavior-Based Pricing of Organic and Conventional Agricultural Products Based on Green Subsidies

This study considers two types of consumers: those without preference difference, and those that prefer organic agricultural products. It constructs two two-stage hoteling behavior-based pricing models and solves for the optimal loyalty price and poaching price of the two types of enterprises. It analyzes the influence of subsidies on the pricing of the two types of products and corporate profits. The study also undertakes numerical simulation for further analysis, finding that green subsidies are negatively correlated with the loyalty price and poaching price of organic agricultural products, but that they will not affect the difference between the two types of prices. When the inherited market of organic agricultural products is dominant, the size of green subsidy affects the relationship between the prices of the two types of products. However, when organic agricultural products do not dominate the initial market, green subsidies do not affect the size of the relationship between the two prices of the two types of products. When the initial market position of organic agricultural products is different, the types of competing customers are different between the two types of enterprises, and the intensity of competition will increase with the increase of subsidies. Green subsidies increase the profits of organic agricultural enterprises and reduce the profits of conventional agricultural enterprises