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The main objective of this paper is to consider model averaging methods for kriging models. This paper proposes a Mallows model averaging procedure for the orthogonal kriging model and demonstrate the asymptotic optimality of the model averaging estimators in terms of mean square error. Simulation studies are conducted to evaluate the performance of the proposed method and compare it with the competitors to demonstrate its superiority. The authors also analyse a real dataset for an illustration. [ABSTRACT FROM AUTHOR]

Nowadays, the intelligent transportation system (ITS) has developed prosperously all over the world. As a key technique in ITS, vehicular ad-hoc network (VANET) supports fast transmitting while bringing security problems simultaneously. To ensure efficiency, those unprotected data transmitting at a high speed can be easily eavesdropped on or forged, which will badly damage the ITS. To authenticate the identities of the vehicles in VANETs, signatures with certificates are often employed in historical research, but seldom study discusses the protection of generated data or mutual authentication between participants in VANETs. In order to tackle the problems above, we propose a new mutual authentication scheme for VANET where the private data can be kept away from attackers. In our scheme, the corresponding manager of each region can deal with the dynamic information of vehicles. The security analysis is also carried out and shown to emphasize the reliability of the scheme, such as anonymity, unlinkability and resistance to replay attacks, etc. Besides the resistance to different attacks, the real-time information secrecy can also be protected in our scheme, which is not achieved in the compared schemes. Moreover, the performance evaluation and simulation with NS-3 show that the packet delivery ratio reaches over 99% in most of the application scenarios, which proves that the scheme is efficient and practical. [ABSTRACT FROM AUTHOR]

Non-adiabatic behaviour induced by the chorus-electron interaction is an important contributor to the radiation belt dynamics, and largely relies on wave frequency distribution. During the geomagnetic storm on August 2, 2016, upper-band, lower-band and extremely low frequency (ELF) chorus waves were simultaneously observed within one orbit period of the Van Allen Probe B. Numerical simulations are performed to investigate the electron evolution by the observed chorus with different frequencies. The results show that various frequency chorus waves have different effects on electron dynamics. For chorus in the range f≈0.3fce−0.7fce, energy diffusion is the dominant process in electron evolutions. For chorus in the range 0.1fce⩽f⩽0.25fce, the pitch angle diffusion tends to be comparable to energy diffusion for Ek>0.5 MeV. For ELF chorus below 0.1fce, the pitch angle diffusion rate is much above the energy diffusion rate, leading to potential scattering losses. [ABSTRACT FROM AUTHOR]

Enormous efforts have been made to target metabolic dependencies of cancer cells for developing new therapies. However, the therapeutic efficacy of glycolysis inhibitors is limited due to their inability to elicit cell death. Hexokinase 2 (HK2), via its mitochondrial localization, functions as a central nexus integrating glycolysis activation and apoptosis resilience. Here we identify that K63-linked ubiquitination by HectH9 regulates the mitochondrial localization and function of HK2. Through stable isotope tracer approach and functional metabolic analyses, we show that HectH9 deficiency impedes tumor glucose metabolism and growth by HK2 inhibition. The HectH9/HK2 pathway regulates cancer stem cell (CSC) expansion and CSC-associated chemoresistance. Histological analyses show that HectH9 expression is upregulated and correlated with disease progression in prostate cancer. This work uncovers that HectH9 is a novel regulator of HK2 and cancer metabolism. Targeting HectH9 represents an effective strategy to achieve long-term tumor remission by concomitantly disrupting glycolysis and inducing apoptosis. Cancer cells develop specific metabolic adaptations. Here, the authors show that in prostate cancer models, the ubiquitin ligase Hect9 promotes tumor growth by accelerating glucose metabolism via ubiquitination of Hexokinase 2, a central regulator of glycolysis. [ABSTRACT FROM AUTHOR]

Lung cancer is currently the leading cause of cancer-related death in worldwide, non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancers. Surgery, platinum-based chemotherapy, molecular targeted agents and radiotherapy are the main treatment of NSCLC. With the strategies of treatment constantly improving, the prognosis of NSCLC patients is not as good as before, new sort of treatments are needed to be exploited. Programmed death 1 (PD-1) and its ligand PD-L1 play a key role in tumor immune escape and the formation of tumor microenvironment, closely related with tumor generation and development. Blockading the PD-1/PD-L1 pathway could reverse the tumor microenvironment and enhance the endogenous antitumor immune responses. Utilizing the PD-1 and/or PD-L1 inhibitors has shown benefits in clinical trials of NSCLC. In this review, we discuss the basic principle of PD-1/PD-L1 pathway and its role in the tumorigenesis and development of NSCLC. The clinical development of PD-1/PD-L1 pathway inhibitors and the main problems in the present studies and the research direction in the future will also be discussed. [ABSTRACT FROM AUTHOR]