On endo-homology of complexes of graphs

AbstractLet L be a subcomplex of a complex K. If the homomorphism from inclusion i∗:Hq(L)→Hq(K) is an isomorphism for all q ⩾ 0, then we say that L and K are endo-homologous. The clique complex of a graph G, denoted by C(G), is an abstract complex whose simplices are the cliques of G. The present paper is a generalization of Ivashchenko (1994) along several directions. For a graph G and a given subgraph F of G, some necessary and sufficient conditions for C(G) to be endo-homologous to C(F) are given. Similar theorems hold also for the independence complex I(G) of G, where I(G) − C(Gc), the clique complex of the complement of G

The Relationship of Pyroptosis-Related Genes, Patient Outcomes, and Tumor-Infiltrating Cells in Bladder Urothelial Carcinoma (BLCA)

Introduction: The role of pyroptosis and its effects on tumor-infiltrating cells (TICs) in the pathogenesis and treatment outcomes of patients with bladder urothelial carcinoma (BLCA) remains unclear.Methods: We conducted a bioinformatics analysis on the pyroptosis-related genes (PRGs) and TICs using data from public domains, and evaluated their impact on the pathogenesis and clinical outcomes of BLCA patients. A risk score based on PRGs and a prognostic risk model that incorporated patient demographics, tumor characteristics, and differentially expressed genes (DEGs) were developed.Results: Twenty-three DEGs of 52 PRGs were identified in BLCA and normal samples from the TCGA database. Missense mutations and single nucleotide polymorphisms in PRGs are the most common genetic abnormalities. Patients with high PRG risk scores showed an inferior survival compared to those with low risk scores. The prognostic risk model based on patient demographics, tumor characteristics, and DEGs showed good predictive values for patient survival at 1, 3, and 5 years in BLCA patients. Caspase-8 (CASP8) was the only intersection gene of the prognostic genes, DEGs, and different genes expressed in tissue. Patients with a high CASP8 expression had improved survival, and an increased CASP8 expression level was observed in activated CD4 memory T cells, follicular T helper cells, resting NK cells, M0 macrophages, and activated dendritic cells. CASP8 expression also showed a positive correlation with the IL7R expression—a key cell marker of CD4 memory T cells. CASP8 expression also showed correlations with immune checkpoints (PDCD1, CD274, and CTLA4) and response to immune checkpoint inhibitors.Conclusion: Our data suggest that PRGs, especially CASP8, showed strong associations with patient outcomes and TICs in BLCA. If validated, these results could potentially aid in the prognostication and guide treatment in BLCA patients

Robust Sliding Mode Predictive Control of Uncertain Networked Control System with Random Time Delay

This paper proposes a sliding mode predictive controller with a new robust global sliding surface for a certain networked control system with random time delay, mismatched parametric uncertainty, and external disturbances. First, the model of the networked control system is established, based on which linear transformation is made to get a new form of the system which does not have time delay term in expression. Then a global sliding surface is proposed followed by the sufficient condition given in the form of linear matrix inequality (LMI) to guarantee system stability and robustness. Subsequently, a sliding mode predictive controller is proposed with modified reaching law as its reference trajectory and the rolling optimization method is combined to provide optimal control input for each step so that chattering can be minimized. Finally, simulations have been made and the results indicate the advantages of the proposed controller in the aspect of convergence speed, chattering suppression, and robustness to uncertainties

Fabrication and Characterization of Short Silicon Nitride Fibers from Direct Nitridation of Ferrosilicon in N2 Atmosphere

Short silicon nitride fibers were fabricated by direct nitridation of ferrosilicon in N2 atmosphere, and their structure and possible growth mechanism were characterized and investigated. The rod-like fibers which were α-Si3N4 with a low degree of crystallization and a high aspect ratio had a diameter of about 4 μm and a length close to a few millimeters. Belt-like fibers with a width about 5 μm and a thickness about 1 μm were also found in the nitrides. Scanning electron microscope (SEM), transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM), and selected area electron diffraction (SAED) investigations indicated that the fibers were single-crystalline α-Si3N4 with few amorphous distributed in the edge region, and the fibers grew by vapor–liquid–solid (VLS) mechanism

Thermodynamics of the production of condensed phases in the CVD process of B<i style="mso-bidi-font-style:normal">_x</i>C with BCl₃-C₃H₆ (propylene)-H₂ precursors

465-472The temperature, pressure and the molar ratio of the injected gas mixture for the deposition of the condensed phases in the CVD process of BxC with BCl3-C3H6 (propylene)-H2 precursors are investigated in detail thermodynamically with a revised database including 329 species. The results show that the composition of the condensed phases is quite sensitive to both temperature and the molar ratios of BCl3/(BCl3+C3H6) and H2/(BCl3+C3H6) while it is less sensitive to pressure. The ideal conditions for the deposition of BxC are BCl3/(BCl3+C3H6) ratio within 0.88~0.92, H2/(BCl3+C3H6) ratio within 10~105.2 and temperature above 1100 K at lower pressures. The co-deposition of C or B with BxC is mainly controlled by the ratios of BCl3/(BCl3+C3H6) and H2/(BCl3+C3H6). The co-deposition of C with BxC should be in low BCl3/(BCl3+C3H6) (0.0~0.88) and H2/(BCl3+C3H6) (10-22.4) ratios while the co-deposition of B with BxC needs higher BCl3/(BCl3+C3H6) (0.92~1.0) and H2/(BCl3+C3H6) (104~105) ratios

Piecewise Adaptive Sliding Mode Control for Aeroengine Networked Control Systems with Resource Constraints

Within the future application of wireless network for the aeroengine control problem, resource constraints (caused by the limitation of hardware) and network traffic restriction must be considered as one of the difficulties to be solved; thus, the network connection and transmission efficiency can be ensured. With focus on the problem of active packed dropout, a MEF-TOD (Maximum Error First-Try Once Discard) scheduling based network parameter and sliding mode joint design method has been proposed. First, a scheduling protocol strained control system and network parameter joint model have been established based on MEF-TOD scheduling strategy, taking sampling period and data packet capacity as unknown network parameters. Subsequently, considering the influence of scheduling strategy, a sliding surface containing a compensation term has been designed, and then a sliding mode parameter and unknown network parameter heuristic joint design method has been developed. Finally, an attenuation factor based piecewise adaptive sliding mode strategy has been designed considering the influence of sampling period on system performance. Simulation results indicate that the joint design method can obtain the network parameter group which has the minimum performance function upper bound, thus achieving relatively high network utilization. The proposed piecewise adaptive sliding mode controller has good dynamic performance and is robust to the packet dropout problem caused by network scheduling and can effectively suppress chattering

Vacuum conditions for tunable wettability transition on laser ablated Ti-6Al-4V alloy surfaces

This work investigates the mechanism of the controllable wettability transition on laser ablated Ti-6Al-4V alloy surfaces with the vacuum treatment. The effects of surface morphologies, vacuum conditions and joint mechanisms are discussed. To achieve stable and controllable wettability transitions, the laser ablated Ti-6Al-4V alloy surfaces were placed in a low vacuum environment to adsorb non-polar organic molecules. The sample appeared an unstable wettability transition, which manifested itself as a change in the apparent contact angle (ACA) with time. High vacuum conditions can accelerate the assembly of organic molecules on the sample surface and achieve a stable wettability transition. Furthermore, by varying the surface morphologies of laser ablated Ti-6Al-4V alloy and the adsorption time of organic molecules, stable and controllable wettability transitions can be achieved at high vacuum conditions