Speed and accuracy of protein synthesis are fundamental parameters for the fitness of living cells, the quality control of translation, and the evolution of ribosomes. The ribosome developed complex mechanisms that allow for a uniform recognition and selection of any cognate aminoacyl-tRNA (aa-tRNA) and discrimination against any near-cognate aa-tRNA, regardless of the nature or position of the...

Deregulation of precursor mRNA splicing is associated with many illnesses and has been linked to age-related chronic diseases. Here we review recent progress documenting how defects in the machinery that performs intron removal and controls splice site selection contribute to cellular senescence and organismal aging. We discuss the functional association linking p53, IGF-1, SIRT1, and ING-1 spl...

The energy efficiency, greenhouse gas (GHG) emissions, and carbon efficiency of paddy rice production were analysed in Sari in the Mazandaran province of Iran during 2011–2012. Data was collected through questionnaires and interviews with paddy producers. The results showed that the net energy gain was 27,932 MJ ha-1 and energy efficiency was 1.83 during production. The results o...

Larger testes are considered the quintessential adaptation to sperm competition. However, the strong focus on testis size in evolutionary research risks ignoring other potentially adaptive features of testicular function, many of which will also be shaped by post-mating sexual selection. Here we advocate a more integrated research programme that simultaneously takes into account the development...

Selection of each major type of Reciprocating, Rotary, Centrifugal and axial Compressor is briefly reviewed. It ls explained how the nondimensional scales of Specific Speed and Speclfic Diameter can be used to select any of the above configuration of Compression machinery at its optimum efficiency range. The paper presents the approach of Engineers Constructors in selecting compressors in petro...

farm machinery managers often need to make complex economic decisions on machinery replacement. repair and maintenance costs can have significant impacts on this economic decision. the farm manager must be able to predict farm machinery repair and maintenance costs. this study aimed to identify a regression model that can adequately represent the repair and maintenance costs in terms of machine...

in this paper the use of farm machinery in sugar beet farms in farsprovince was studied. the necessary data, with two-stage cluster sampling method in fasa, eghlid and darab cities on 2004- 2005 were collected. from 203 farmers selected for the study. 113 of them were in high level mechanization group and 90 of them were in low level mechanization group. in this study, the effect of farm machin...

With the improvement of complexity and reliability mechanical equipment, it has been difficult for commonly used variational modal decomposition method vibration signal rotating machinery to meet current practical engineering requirements. In order further improve adaptability, processing efficiency, robustness fault diagnosis methods, a collaborative hybrid element heuristic multiobjective opt...