Pathway analysis following association study

Genome-wide association studies often emphasize single-nucleotide polymorphisms with the smallest p-values with less attention given to single-nucleotide polymorphisms not ranked near the top. We suggest that gene pathways contain valuable information that can enable identification of additional associations. We used gene set information to identify disease-related pathways using three methods: gene set enrichment analysis (GSEA), empirical enrichment p-values, and Ingenuity pathway analysis (IPA). Association tests were performed for common single-nucleotide polymorphisms and aggregated rare variants with traits Q1 and Q4. These pathway methods were evaluated by type I error, power, and the ranking of the VEGF pathway, the gene set used in the simulation model. GSEA and IPA had high power for detecting the VEGF pathway for trait Q1 (91.2% and 93%, respectively). These two methods were conservative with deflated type I errors (0.0083 and 0.0072, respectively). The VEGF pathway ranked 1 or 2 in 123 of 200 replicates using IPA and ranked among the top 5 in 114 of 200 replicates for GSEA. The empirical enrichment method had lower power and higher type I error. Thus pathway analysis approaches may be useful in identifying biological pathways that influence disease outcomes

Improving human-robot interactivity for tele-operated industrial and service robot applications

In industrial robotics applications, teach pendant has been widely used by human operators to pre-define action trajectories for robot manipulators to execute as primitives. This hard-coding approach is only good for low-mix-highvolume jobs with sparse trajectory way-points. In this paper, we present a novel industrial robotic system designed for applications where human-robot interaction is key for efficient execution of actions such as high-mix-low-volume jobs. The proposed system comprises a robot manipulator that controls a tool (such as a soldering iron) to interact with the required workpiece, a networking server for remote tele-operation, and an integrated user interface that allows the human operator to better perceive the remote operation and to execute actions with greater ease. A user study is conducted to understand the merits of the proposed system. Results indicate that human can operate the system with ease and complete tasks more quickly and that the system can improve application efficiency

Multi-threshold second-order phase transition

We present a theory of the multi-threshold second-order phase transition, and experimentally demonstrate the multi-threshold second-order phase transition phenomenon. With carefully selected parameters, in an external cavity diode laser system, we observe second-order phase transition with multiple (three or four) thresholds in the measured power-current-temperature three dimensional phase diagram. Such controlled death and revival of second-order phase transition sheds new insight into the nature of ubiquitous second-order phase transition. Our theory and experiment show that the single threshold second-order phase transition is only a special case of the more general multi-threshold second-order phase transition, which is an even richer phenomenon.Comment: 5 pages, 3 figure

Cell Cycle Arrest Induces Lipid Droplet Formation and Confers Ferroptosis Resistance

How cells coordinate cell cycling with cell survival and death remains incompletely understood. Here, we show that cell cycle arrest has a potent suppressive effect on ferroptosis, a form of regulated cell death induced by overwhelming lipid peroxidation at cellular membranes. Mechanistically, cell cycle arrest induces diacylglycerol acyltransferase (DGAT)-dependent lipid droplet formation to sequester excessive polyunsaturated fatty acids (PUFAs) that accumulate in arrested cells in triacylglycerols (TAGs), resulting in ferroptosis suppression. Consequently, DGAT inhibition orchestrates a reshuffling of PUFAs from TAGs to phospholipids and re-sensitizes arrested cells to ferroptosis. We show that some slow-cycling antimitotic drug-resistant cancer cells, such as 5-fluorouracil-resistant cells, have accumulation of lipid droplets and that combined treatment with ferroptosis inducers and DGAT inhibitors effectively suppresses the growth of 5-fluorouracil-resistant tumors by inducing ferroptosis. Together, these results reveal a role for cell cycle arrest in driving ferroptosis resistance and suggest a ferroptosis-inducing therapeutic strategy to target slow-cycling therapy-resistant cancers

Boosting the piezoelectric property of relaxor ferroelectric single crystal via active manipulation of defect dipole polarization

To further enhance the property of piezoelectric materials is of great significance to improve the overall performance of electro-mechanical devices. Here in this work, we propose a thermal annealing and high temperature poling approach to achieve significantly enhanced piezoelectricity in Pb(In1/2Nb1/2)O3[sbnd]Pb(Mg1/3Nb2/3)O3[sbnd]PbTiO3 (PIN-PMN-PT) crystals with a morphotropic phase boundary (MPB) composition. The main idea of our approach is to realize a more sufficiently polarized crystal via active manipulation of defects and orientation of defect polarization. Manipulation of defect dipoles by the high temperature poling is proved by the piezo-response force microscopy. Finally, a d33 of 3 300 pC/N and a SE of 0.25% are obtained, nearly 60% higher than that of conventionally poled crystals. Moreover, such a boosting of piezoelectric property is obtained under a maintained Curie temperature. Our research not only reveals the active control of defect dipole via modified poling method in the PIN-PMN-PT crystal, but also provides a feasible strategy to further improve the property of piezoelectric materials. © 2022 The AuthorsS20212BDH80017; 2017ktpt-21, 2018TD-024; National Natural Science Foundation of China, NSFC: 51761145024, 51772239, 52102143, 62001369This work is supported by the National Nature Science Foundation of China (Grant Nos. 52102143 , 51772239 , 62001369 and 51761145024 ), Shaanxi province project ( 2017ktpt-21 and 2018TD-024 ), Jiangxi Technological Innovation Guidance Science and Technology Plan (Grant No. S20212BDH80017 )

Realization of vertically aligned, ultra-high aspect ratio InAsSb nanowires on graphite

The monolithic integration of InAs1–xSbx semiconductor nanowires on graphitic substrates holds enormous promise for cost-effective, high-performance, and flexible devices in optoelectronics and high-speed electronics. However, the growth of InAs1–xSbx nanowires with high aspect ratio essential for device applications is extremely challenging due to Sb-induced suppression of axial growth and enhancement in radial growth. We report the realization of high quality, vertically aligned, nontapered and ultrahigh aspect ratio InAs1–xSbx nanowires with Sb composition (xSb(%)) up to ∼12% grown by indium-droplet assisted molecular beam epitaxy on graphite substrate. Low temperature photoluminescence measurements show that the InAs1–xSbx nanowires exhibit bright band-to-band related emission with a distinct redshift as a function of Sb composition providing further confirmation of successful Sb incorporation in as-grown nanowires. This study reveals that the graphite substrate is a more favorable platform for InAs1–xSbx nanowires that could lead to hybrid heterostructures possessing potential device applications in optoelectronics