Qualitative analysis on the diffusive Holling-Tanner predator-prey model

We consider the diffusive Holling–Tanner predator–prey model subject to the homogeneous Neumann boundary condition. We first apply Lyapunov function method to prove some global stability results of the unique positive constant steadystate. And then, we derive a non-existence result of positive non-constant steady-states by a novel approach that can also be applied to the classical Sel’kov model to obtain the non-existence of positive non-constant steady-states if 0 < p ≤ 1

Vanishing diffusion limit and boundary layers for a nonlinear hyperbolic system with damping and diffusion

We consider an initial and boundary value problem for a nonlinear hyperbolic system with damping and diffusion. This system was derived from the Rayleigh–Benard equation. Based on a new observation of the structure of the system, two identities are found; then, the following results are proved by using the energy method. First, the well-posedness of the global large solution is established; then, the limit with a boundary layer as some diffusion coefficient tending to zero is justified. In addition, the $L^2$ convergence rate in terms of the diffusion coefficient is obtained together with the estimation of the thickness of the boundary layer

HIV associated cell death: Peptide-induced apoptosis restricts viral transmission.

The human immunodeficiency virus (HIV) is still a global pandemic and despite the successful use of anti-retroviral therapy, a well-established cure remains to be identified. Viral modulation of cell death has a significant role in HIV pathogenesis. Here we sought to understand the major mechanisms of HIV- induced death of lymphocytes and the effects on viral transmission. Flow cytometry analysis of lymphocytes from five latent HIV-infected patients, and HIV IIIB-infected MT2 cells demonstrated both necrosis and apoptosis to be the major mechanisms of cell death in CD4+ and CD4-/CD8- lymphocytes. Significantly, pro-apoptotic tumor necrosis factor (TNF) peptide (P13) was found to inhibit HIV-related cell death and reduced viral transmission. Whereas pro-necrotic TNF peptide (P16) had little effect on HIV-related cell death and viral transmission. Understanding mechanisms by which cell death can be manipulated may provide additional drug targets to reduce the loss of CD4+ cells and the formation of a viral reservoir in HIV infection

Research Progress of Ionic Thermoelectric Materials for Energy Harvesting

Thermoelectric material is a kind of functional material that can mutually convert heat energy and electric energy. It can convert low-grade heat energy (less than 130°C) into electric energy. Compared with traditional electronic thermoelectric materials, ionic thermoelectric materials have higher performance. The Seebeck coefficient can generate 2–3 orders of magnitude higher ionic thermoelectric potential than electronic thermoelectric materials, so it has good application prospects in small thermoelectric generators and solar power generation. According to the thermoelectric conversion mechanism, ionic thermoelectric materials can be divided into ionic thermoelectric materials based on the Soret effect and thermocouple effect. They are widely used in pyrogen batteries and ionic thermoelectric capacitors. The latest two types of ionic thermoelectric materials are in this article. The research progress is explained, and the problems and challenges of ionic thermoelectric materials and the future development direction are also put forward

Small RNA zippers lock miRNA molecules and block miRNA function in mammalian cells.

MicroRNAs (miRNAs) loss-of-function phenotypes are mainly induced by chemically modified antisense oligonucleotides. Here we develop an alternative inhibitor for miRNAs, termed \u27small RNA zipper\u27. It is designed to connect miRNA molecules end to end, forming a DNA-RNA duplex through a complementary interaction with high affinity, high specificity and high stability. Two miRNAs, miR-221 and miR-17, are tested in human breast cancer cell lines, demonstrating the 70∼90% knockdown of miRNA levels by 30-50 nM small RNA zippers. The miR-221 zipper shows capability in rescuing the expression of target genes of miR-221 and reversing the oncogenic function of miR-221 in breast cancer cells. In addition, we demonstrate that the miR-221 zipper attenuates doxorubicin resistance with higher efficiency than anti-miR-221 in human breast cancer cells. Taken together, small RNA zippers are a miRNA inhibitor, which can be used to induce miRNA loss-of-function phenotypes and validate miRNA target genes

Qualitative analysis on the diffusive Holling–Tanner predator–prey model

We consider the diffusive Holling–Tanner predator–prey model subject to the homogeneous Neumann boundary condition. We first apply Lyapunov function method to prove some global stability results of the unique positive constant steady-state. And then, we derive a non-existence result of positive non-constant steady-states by a novel approach that can also be applied to the classical Sel'kov model to obtain the non-existence of positive non-constant steady-states if $0<p\leq 1$

Long non‑coding RNA linc00239 promotes malignant behaviors and chemoresistance against doxorubicin partially via activation of the PI3K/Akt/mTOR pathway in acute myeloid leukaemia cells

Long non-coding RNAs (lncRNAs) are known to be involved in the processes of tumourigenesis and malignant behaviours in many types of cancer, including acute myeloid leukaemia (AML). Accumulating evidence has revealed that novel lncRNAs exerted critical roles in these processes. In the present study, we investigated the effects of lncRNA linc00239 (NR_026774.1), which is 662 nucleotides (nt) in length and was found to be upregulated in AML patients, on malignant behaviours and chemosensitivity in AML cells, including KG-1 and HL-60. linc00239 expression was detected in KG-1 and HL-60 cells by quantitative PCR and northern blotting, and it was found that linc00239 is detectable by both of these assays. After knockdown or overexpression of linc00239 in AML cells, the results revealed that the presence of linc00239 promoted proliferation, colony formation and migration ability. Furthermore, the presence of linc00239 increased chemoresistance to doxorubicin in AML cells partially by preventing doxorubicin-induced apoptotic cell death. It was also determined that the presence of linc00239 was related to activation of the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway. Inhibition of PI3K/Akt/mTOR using 1 µM NVP-BEZ235 (BEZ) abolished the inhibitory effect of linc00239 on chemosensitivity and the preventative effect on doxorubicin-induced cell death. Collectively, our data revealed that linc00239 is a novel tumour promoter in AML cells and indicated that it is a potential therapeutic target

JOINT DESIGN AND MOTION RESEARCH OF ENTERTAINMENT ANTHROPOMORPHIC ROBOT

Joint design and motion research is key to the design and research of entertainment Anthropomorphic robot,It direct impact on attitude and balance of robot motion. So,we focus on research Joint structure design and joint movement. Joint of robot hand and foot is designed by human engineering principle and finite element analysis method. Solution of joint position and velocity is obtained base on establishing joint coordinates and calculation. Effective solve robot movement in the process of stability with analysis of the balance of motion. Find a way to achieve robot walking,turning and lateral movement and other humanoid movements by the study the effect of the slip and calculation of the sliding force. A fixed frequency current control method is proposed,and realized robot key gait planning