Determination of protection range of mining upper protective layers and its numerical simulation

Aiming at the limitation of the traditional method for determination of protection region, combined with the actual situation of a mine, a new method for determination of protection region was put forward （including the protection of working face layout and development direction）, that is, gas flow observation analysis on the spot and gas content contrast method. The protection region was determined by gas flow observation analysis, gas content contrast, and computer numerical simulation combined with engineering practice. In the process of gas content test, the fixed sampling method ＂big hole drill reaming, small orifice drill rod connected with core tube＂ was employed. The results show that the determined protection region is in accordance with the actual site situation. The fixed sampling method ensures the accuracy of gas measurement of gas content.

Medullary thyroid cancer:single-cell transcriptome and tumor evolution

Background Medullary thyroid cancer(MTC)is a rare neuroendocrine tumor that originates from the parafollicular C cells of thyroid gland.Understanding the fundamental pathophysiology of MTC is essential for clinical manage-ment.Single-cell RNA sequencing(scRNA-seq)technology is a powerful tool for identifying distinct cell types,offering a new biological foundation for comprehending the MTC ecosystem and developing precise treatment.Methods Formalin fixed and paraffin-embedded(FFPE)samples of primary and adjacent non-cancerous tissues of three MTC cases were collected,and single-cell transcriptome data of MTC were obtained by using scRNA-seq technology.Annotated cell subpopulations were categorized and functionally enriched by principal component analysis,differential gene expression,and cell clustering analysis,to explore the biological process of tumor evolution that may be involved in each cell subpopulation.The copy number variation(CNV)profile was used to distinguish the malignancy of parafollicular thyroid cells,and the evolutionary trajectories of normal cells and tumor cells were revealed by the proposed time series analysis.The highly expressed genes in each cell subpopulation were analyzed by the FindAllMarker function of Seurat software,and verified by immunohistochemistry and fluorescence in situ hybridization.The prognostic value of specific cell subtypes was validated using large-scale public datasets.Results A total of 32,544 cells were obtained from the MTC tissue samples and 11,751 cells from the adjacent non-cancerous samples,which were classified into 7 heterogenous subpopulations by using R package of Seurat mod-ule.Copy number variations(CNVs)were significantly higher in tumor tissues than in adjacent non-tumor samples,predominantly enriched in subtypes C2 and C4.In addition,the pseudo-time for trajectory analysis suggested that the evolution of MTC tumor cells might begin with the C2 subtype,then transition to the early cancer sub-group C3,and further differentiate into four major malignant cell subpopulations C0,C1,C5 and C6.Survival analysis of a thyroid cancer cohort using the TCGA dataset revealed that high expression of genes linked to the C0 subcluster was correlated with poorer overall survival compared to low expression.Immunohistochemical staining showed that MAP3K4 was highly expressed in MTC tissues compared to adjacent non-cancerous tissues.Fluorescence in situ hybridization also confirmed the amplification of these two genes in MTC samples.Conclusions By conducting scRNA-seq on FFPE samples,we mapped the single-cell transcriptome of MTC,uncov-ering the tumor heterogeneity and unique biological features of each cellular subpopulation.The biological roles of identified tumor cell subpopulations such as C0 and C3 subtypes of parafollicular cells suggested the potential to discover new therapeutic targets and biomarkers for MTC,providing valuable insights for future translational and clinical research.

Mate choice decisions by searchers

For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the as- sumption that searchers--and, for applied purposes, researchers--assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to de- rive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formu- lated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. More general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 （2）： 184-199, 2013].