Fault-tolerant topology in the wireless sensor networks for energy depletion and random failure

Nodes in the wireless sensor networks （WSNs） are prone to failure due to energy depletion and poor environment, which could have a negative impact on the normal operation of the network. In order to solve this problem, in this paper, we build a fault-tolerant topology which can effectively tolerate energy depletion and random failure. Firstly, a comprehensive failure model about energy depletion and random failure is established. Then an improved evolution model is presented to generate a fault-tolerant topology, and the degree distribution of the topology can be adjusted. Finally, the relation between the degree distribution and the topological fault tolerance is analyzed, and the optimal value of evolution model parameter is obtained. Then the target fault-tolerant topology which can effectively tolerate energy depletion and random failure is obtained. The performances of the new fault tolerant topology are verified by simulation experiments. The results show that the new fault tolerant topology effectively prolongs the network lifetime and has strong fault tolerance.

Synergetic lethal energy depletion initiated by cancer cell membrane camouflaged nano-inhibitor for cancer therapy

Mitochondrial bioenergy plays a vital role in the occurrence and development of cancer.Although strategies to impede mitochondrial energy supply have been rapidly developed,the anticancer efficacy is still far from satisfactory,mainly attributed to the hybrid metabolic pathways of mitochondrial oxidative phosphorylation(OXPHOS)and glycolysis.Herein,we construct a cancer cell membrane camouflaged nano-inhibitor,mTPPa-Sy nanoparticle(NP),which co-encapsulates OXPHOS inhibitor(mitochondrial-targeting photosensitizers:TPPa)and glycolysis inhibitor(syrosingopine(Sy))for synergistically blocking the two different energy pathways.The mTPPa-Sy NPs exhibit precision tumor-targeting due to the high affinity between the biomimic membrane and the homotypic cancer cells.Under laser irradiation,the mitochondrial-targeting TPPa,which is synthesized by conjugating pyropheophorbide a(PPa)with triphenylphosphin,produces excessive reactive oxygen species(ROS)and further disrupts the OXPHOS.Interestingly,OXPHOS inhibition reduces O_(2) consumption and improves ROS production,further constructing a closed-loop OXPHOS inhibition system.Moreover,TPPa-initiated OXPHOS inhibition in combination with the Sytriggered glycolysis inhibition results in lethal energy depletion,significantly suppressing tumor growth even after a single treatment.Our findings highlight the necessity and effectiveness of synergetic lethal energy depletion,providing a prospective strategy for efficient cancer therapy.

Monte Carlo simulation of prompt γ-ray spectra from depleted uranium under D-T neutron irradiation and electron recoil spectra in a liquid scintillator detector

To overcome the problem of inefficient computing time and unreliable results in MCNP5 calculation, a two-step method is adopted to calculate the energy deposition of prompt γ-rays in detectors for depleted uranium spherical shells under D-T neutron irradiation. In the first step, the γ-ray spectrum for energy below 7 MeV is calculated by MCNP5 code; secondly, the electron recoil spectrum in a BC501 A liquid scintillator detector is simulated based on EGSnrc Monte Carlo Code with the γ-ray spectrum from the first step as input. The comparison of calculated results with experimental ones shows that the simulations agree well with experiment in the energy region 0.4–3 MeV for the prompt γ-ray spectrum and below 4 MeVee for the electron recoil spectrum. The reliability of the two-step method in this work is validated.