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Statistical inference for high-dimensional survival data is important for obtaining valid scientific results in many research areas, including biomedical studies and financial risk management. In this paper, a novel framework for feature selection in Cox model is proposed, which achieves false discovery rate (FDR) control asymptotically. The key step is to construct a sequence of ranking statistics based on two independent estimators of the regression coefficients. The FDR control is reached by choosing a data-driven threshold along the ranking of symmetric-based statistics. The de-sparsified estimator and uneven data splitting strategy are employed to improve the robustness of variable selection results and the power in finite sample analysis. We establish the asymptotic FDR control property for the proposed approach at any designated level. Extensive simulation studies and an empirical application on a P2P loan dataset confirm the robustness of the proposed method in FDR control, and show that it often leads to higher power among competitors. [ABSTRACT FROM AUTHOR]

Due to extensive introduction and breeding, the taxonomic relationships of Lonicera L. are unclear. Alternative scientific methods are needed to explore the classification of these new Lonicera. In this paper, the pollen morphology characteristics, karyotype features, and floral and fruit pigment components of 13 taxa of Lonicera were analyzed by means of scanning electron microscopy, karyotype analysis, High Performance Liquid Chromatography Mass Spectrometry (HPLC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS). The 13 representatives of Lonicera were divided into groups of four, three, three and three taxa through the analysis of pollen morphology characteristics, karyotype features, floral composition and fruit pigment composition, respectively. Lonicera ruprechtiana and Lonicera tatarica always clustered together. Five hybrids, including Lonicera korolkow × Lonicera maackii and Lonicera korolkow × Lonicera tatarica No. 8 can generally be clustered with their parents. These results indicate that the analysis of pollen morphology characteristics, karyotype features, and floral and fruit pigment composition has value and significance for the study of systematic classification and relationships, and the conclusions of this study partially support morphological taxonomy. [ABSTRACT FROM AUTHOR]

In vegetable production, Chinese cabbage can readily accumulate cadmium (Cd) into its edible parts and exceed food safety standards. However, there are still some ecotypes that respond differently to cadmium stress. This study aimed to investigate the differences of Cd-induced (0, 10, 50, 100, 200 µM) response under hydroponic culture between two Chinese cabbage ecotypes which were promoted in northeastern China from the characteristics of biomass, uptake kinetic, accumulation, and initial oxidative stress. In this paper, it was confirmed that Jinfeng (JF) was a Cd-tolerant cultivar and had low Cd accumulation in edible part, while Qiutian (QT) was Cd-sensitive, exhibiting a faster Cd uptake rate but lacking effective Cd detoxication mechanisms, and was severely damaged by 10 µM Cd treatment. Conversely, even at a high Cd concentration of 200 µM, Jinfeng had weaker biomass inhibition, lower root Cd affinity, more difficult root-to-leaf translocation, and stronger antioxidant enzyme activity than Qiutian. In conclusion, Jinfeng can endure mild Cd stress (<10 µM), and Qiutian can be used as a Cd indicator. This study provides reliable materials and related data support for vegetable production in areas with mild Cd pollution. Novelty statement: This work further investigates the unique features of low-Cd accumulator in Chinese cabbage (Brassica pekinensis L.) seedlings as an interesting material for vegetable production in areas with mild Cd pollution. It also explains the differences between Cd-tolerant and Cd-sensitive cultivars under different cadmium stress levels and how these differences can alter their response. With the increase of Cd concentration, Cd-tolerant cultivars compared to Cd-sensitive cultivars showed less biomass decrease, lower accumulation, lower TF, more chemically stable Cd in roots and more active antioxidant enzymes under the same Cd stress level. With the development of seedlings, the uptake of Cd in roots and the translocation to the leaves were effectively restricted by the poor Cd affinity of roots, the conversion of Cd chemical forms and the promotion of antioxidase activities, in a Cd-tolerant low accumulator, Jinfeng. [ABSTRACT FROM AUTHOR]

We examine diversification when cryptocurrencies are included in investment portfolios, around China prohibiting initial coin offerings on 4 September 2017. We discover, once we account for liquidity, that all portfolio diversification benefits of cryptocurrencies are eliminated. [ABSTRACT FROM AUTHOR]

In this article, we empirically examine the cryptocurrency market reaction to china prohibiting initial coin offerings, on the 4 September 2007 for the 100 largest cryptocurrencies. The announcement has a significant negative but temporary impact on cryptocurrency returns and liquidity. [ABSTRACT FROM AUTHOR]

The purpose of this cross-sectional study was to compare teacher candidates' sense of self-efficacy across institutions and at two different points within the teacher preparation program. Teacher candidate characteristics such as age and hometown were also explored in relation to reported levels of self-efficacy. Data in this study were collected from 143 teacher candidates enrolled at three Midwest institutions utilizing the Teachers' Sense of Efficacy Scale (TSES). Data analysis identified no statistically significant differences in teacher candidates' self-efficacy across three institutions, at two different points in the teacher preparation program, or based on age or hometown. Rasch results indicated that the TSES was invariant across age and teacher preparation programs. Implications for future research and teacher education are discussed. [ABSTRACT FROM AUTHOR]

A general multi-scale strategy is presented for modeling the mechanical environment of a group of neurons that were embedded within a collagenous matrix. The results of the multi-scale simulation are used to estimate the local strains that arise in neurons when the extracellular matrix is deformed. The distribution of local strains was found to depend strongly on the configuration of the embedded neurons relative to the loading direction, reflecting the anisotropic mechanical behavior of the neurons. More importantly, the applied strain on the surrounding extracellular matrix is amplified in the neurons for all loading configurations that are considered. In the most severe case, the applied strain is amplified by at least a factor of 2 in 10% of the neurons' volume. The approach presented in this paper provides an extension to the capability of past methods by enabling the realistic representation of complex cell geometry into a multi-scale framework. The simulation results for the embedded neurons provide local strain information that is not accessible by current experimental techniques. [ABSTRACT FROM AUTHOR]

Transmissible gastroenteritis virus (TGEV) infection causes acute enteritis in swine of all ages, and especially in suckling piglets. Small intestinal inflammation is considered a central event in the pathogenesis of TGEV infections, and nuclear factor-kappa B (NF-κB) is a key transcription factor in the inflammatory response. However, it is unclear whether NF-κB is crucial for inducing inflammation during a TGEV infection. Our results show that NF-κB was activated in swine testicular (ST) cells and intestinal epithelial cell lines J2 (IPEC-J2) cells infected with TGEV, which is consistent with the up-regulation of pro-inflammatory cytokines. Treatment of TGEV-infected ST cells and IPEC-J2 cells with the NF-κB-specific inhibitor caused the down-regulation of pro-inflammatory cytokine expression, but did not significantly affect TGEV replication. Individual TGEV protein screening results demonstrated that Nsp2 exhibited a high potential for activating NF-κB and enhancing the expression of pro-inflammatory cytokines. Functional domain analyzes indicated that the first 120 amino acid residues of Nsp2 were essential for NF-κB activation. Taken together, these data suggested that NF-κB activation was a major contributor to TGEV infection-induced inflammation, and that Nsp2 was the key viral protein involved in the regulation of inflammation, with amino acids 1-120 playing a critical role in activating NF-κB. Abbreviations: TCID50: 50% tissue culture infectious dose; DMEM: Dulbecco's Modified Eagle Medium; eNOS: Endothelial nitric oxide synthase; FBS: fetal bovine serum; IFA: Indirect immunofluorescence; IκB: inhibitor of nuclear factor kappa-B; IL: interleukin; IPEC-J2: intestinal epithelial cell lines J2; IKK: IκB kinase; Luc: luciferase reporter gene; mAbs: monoclonal antibodies; MOI: multiple of infection; Nsp: nonstructural protein; NF-κB: nuclear factor-kappa ; ORFs: open reading frames; PBS: phosphate-buffered saline; p65 p-p65: phosphorylated; RT-PCR: reverse transcription PC; SeV: Sendai virus; ST: swine testicular; TGEV: Transmissible gastroenteritis virus; TNF-α: tumor necrosis factor α; UV-TGEV: Ultraviolet light-inactivated TGEV; ZnF: zinc finger [ABSTRACT FROM AUTHOR]

Soil fauna is an important component in soil ecosystems. This study tested whether conservation tillage or conventional tillage of a black soil (Udic Mollisol) field in Northeast China could affect its soil fauna communities. Two different conservation tillage systems, no-tillage (NT) and reduced tillage (RT), as well as a conventional rotary tillage system (CT), were chosen for this study. There were 4562 individuals isolated from this study, which included two orders and 35 families. Acariformes was the most abundant family and represented 91.56% of the total faunal abundance. The abundance and the number of faunal families were higher in conservation tillage systems than in the CT. The RT system had the highest individual number of soil fauna among three tillage methods. The faunal accumulation in the soil surface also was significantly higher in the two conservation tillage systems than in the CT. Our results indicate that the conservation tillage systems could protect the soil fauna in the soil ecosystem better than the CT. [ABSTRACT FROM AUTHOR]