A survey of powertrain configuration studies on hybrid electric vehicles
Authors: Zhuang, Weichao; Li (Eben), Shengbo; Zhang, Xiaowu; Kum, Dongsuk; Song, Ziyou; Yin, Guodong; Ju, Fei
Global warming, air pollution, and fuel depletion have accelerated the deployment of hybrid electric vehicles (HEVs). Apart from the energy management, the configuration of hybrid powertrains plays a central role in achieving better fuel economy and enhanced drivability. This paper comparatively summarizes the configurations, modeling, and optimization techniques of HEVs. Four types of hybrid powertrain configurations available in the market, i.e., series, parallel, power-split and multi-mode, are introduced firstly, followed by their state-of-the-art and pros/cons. Among all configurations, multi-mode hybrid powertrains are observed to have the potential for utilizing the benefits of the other three types by switching the operating modes. Subsequently, the configuration generation and modeling techniques are summarized. By adopting the automated modeling method, the entire design space can be explored exhaustively, and 14 feasible configuration types are classified based on the binary tree. Finally, the research gaps and future trends of HEV configuration studies are discussed.
CRISPR-CAS Replacing Antiviral Drugs against HIV: An Update
CRITICAL REVIEWS IN EUKARYOTIC GENE EXPRESSION
Authors: Hashmat, Rabia; Yousaf, Muhammad Zubair; Rahman, Ziaur; Anjum, Khalid Mahmood; Yaqub, Atif; Imran, Muhammad
Various antiretroviral drugs do not kill or cure the human immunodeficiency virus (IIIV) but do prevent the replication of the virus. The combination of antiretroviral drugs is known as highly active antiretroviral therapy (HAART). Current drug therapies effectively suppress HEV-1 replication but do not inactivate the provirus that persists in latent reservoirs. Guide RNA (gRNA)-directed CRISPR/Cas9 system can be used for sequence-specific attacks on this proviral DNA. The biggest achievement might be the complete elimination of HIV from infected cells. A study revealed that the tail injection, in transgenic mice and rats having HIV-1 genome, of an adenoassociated virus (AAV) vector expressing a short version of the Cas9 endonuclease (saCas9) and the gRNAs resulted in the cleavage of integrated HIV-1 DNA and excision of a DNA fragment spanning between the LTR and Gag gene in the spleen, liver, heart, kidney, and circulating lymphocytes. HIV-1 has capacity to escape the attack on its genome from most of inhibitors. Thus, to achieve successful antiretroviral treatment, combinations of several antiviral therapies have been applied that are based on two important facts. The first is that multiple drugs lead to synergistic or additive inhibition, and the second is that the combinational therapy increases chances of drug resistance. The success that has been achieved with the help of the genetically engineered tool CRISPR is that dCas9 protein alone can efficiently silence viral gene expression in bacteria with sgRNA. All the reported investigations have indicated that CRISPR/Cas9 can be used as immune machinery into human cells in the form of novel antivirus tools.