Relationships between ionospheric parameters derived from ionosonde observations and characteristics of post-sunset GHz scintillation during high solar activities(2012−2013)at Sanya(18.3°N,109.6°E),China

In this study,we present characteristics of post-sunset GHz scintillation occurrence and their correlations with ionospheric parameters derived from ionosonde observations in high solar activity years(2012−2013)of solar cycle 24 at Sanya(18.3°N,109.6°E;dip lat.:12.8°N),China.The analyzed data include the F_(2)-layer’s critical frequency(foF_(2)),peak height(h_(m)F_(2)),and minimum virtual height(h’F),as well as the scale height around the F_(2)-layer peak(H_(m)),and virtual height(h’F_(5))and true height(hF_(5))measured at 5 MHz.We have investigated relationships between the equinoctial asymmetry of these scintillations and these ionospheric parameters.In addition,we calculate the growth rates of Rayleigh−Taylor instability on the basis of the ionosonde measurements and theoretical models,respectively.We find that the equinoctial asymmetry of scintillation onset time is associated with the scale length of the vertical electron density gradient(L),which has been shown to affect the growth of Rayleigh−Taylor instability at the bottom of the F-layer.The seasonal variations of foF_(2),H_(m)and scale length of vertical electron density gradient appear to cause the seasonal variations of scintillation occurrence;the equinoctial asymmetry of scintillation occurrence rate over low latitudes appears to be related to background electron density and vertical drifts in the F-layer around time of sunset.Further study is required to explain the observed correlational weakness in low latitudes between scintillation strength,represented by the daily maximum S4,and daily maximum values of foF_(2),h_(m)F_(2),h’F,H_(m),and also the drifts.

基于模式产地的分子证据澄清南平鳞毛蕨的分类学地位

地球上有多少物种一直以来都是人们极度关注的问题,而存疑物种是造成该问题难以解决的重要阻碍之一。目前,模式标本是存疑物种得以确定的唯一凭证标准,然而,因其特殊的分类学地位而难以进行有效的观察和研究。因此,前往模式产地寻找存疑物种的原始信息成为最有效的替代途径。随着分子生物学,特别是DNA条形码技术在物种分类与鉴定中的广泛应用,准确而快速鉴定存疑物种成为可能。以存疑物种——南平鳞毛蕨(Dryopteris yenpingensis)为例,利用来自模式产地的分子数据进行DNA条形码分析,并结合形态学特征澄清了南平鳞毛蕨的分类学地位,确定南平鳞毛蕨与荔波鳞毛蕨(D.liboensis)为同一物种,同意将荔波鳞毛蕨作为其异名。研究结果和方法可为今后澄清更多存疑物种的分类学地位提供参考。

基于孢子形态和分子证据探讨鳞盖蕨属(碗蕨科)系统分类

孢粉学是解决植物分类中疑难类群物种微形态分化的重要方法,随着分子系统学的发展,结合这两门学科的优势可以更加有效地解决疑难类群的分类学问题.鳞盖蕨属(Microlepia)是一个分类困难的疑难类群,采用孢粉学与分子系统学一一对应的方法,以及居群取样方式,选取280份样本,联合4个叶绿体片段(rbcL、trnL-F、psbA-trnH和rps4),采用最大似然法和贝叶斯法构建该属的系统发生关系,在此基础上对凭证标本中100份材料的孢子进行观察和分析.综合分子系统学和孢粉学的研究结果,得出结论;(1)在形态学研究中广泛被接受的15个物种得到了单系支持,并厘清了分类困难的复合群;(2)发现边缘鳞盖蕨(M.marginata)可能存在隐性种;(3)建议恢复过去归并处理为异名的瑶山鳞盖蕨(M.yaoshanica)、罗浮鳞盖蕨(M.Iofoushanensis)、四川鳞盖蕨(M.szechuanica)以及滇西鳞盖蕨(M.subspeluncae);(4)提出鳞盖蕨属可能存在杂交现象;(5)提出鳞盖蕨属完整的属下分类建议.

Homeobox B8 Targets Sterile Alpha Motif Domain-Containing Protein 9 and Drives Glioma Progression

Gliomas are the most commonly occurring tumors of the central nervous system. Glioblastoma multiforme (GBM) is the most malignant and aggressive brain cancer in adults. Further understanding of the mechanisms underlying the aggressive nature of GBM is urgently needed. Here we identified homeobox B8(HOXB8), a member of the homeobox family, as a crucial contributor to the aggressiveness of GBM. Data mining of publicly accessible RNA sequence datasets and our patient cohorts confirmed a higher expression of HOXB8 in the tumor tissue of GBM patients, and a strong positive correlation between the expression level and pathological grading of tumors and a negative correlation between the expression level and the overall survival rate. We next showed that HOXB8 promotes the proliferation and migration of glioblastoma cells and is crucial for the activation of the PI3K/AKT pathway and expression of epithelial–mesenchymal transition-related genes, possibly through direct binding to the promoter of SAMD9 (Sterile Alpha Motif Domain-Containing Protein 9) and activating its transcription. Collectively, we identified HOXB8 as a critical contributor to the aggressiveness of GBM, which provides insights into a potential therapeutic target for GBM and opens new avenues for improving its treatment outcome.

Mitochondria as the Essence of Yang Qi in the Human Body

The concept of Yang Qi in Traditional Chinese Medicine(TCM)has many similarities with mitochondria in modern medicine.Both are indispensable to human beings and closely related to life and death.This article discusses the similarities in various aspects between mitochondria and Yang Qi,including body temperature,aging,newborns,circadian rhythm,immunity,and meridian.It is well-known that Yang Qi is vital for human health.Interestingly,decreased mitochondrial function is thought to be key to the development of various diseases.Here,we further explain diseases induced by Yang Qi deficiency,such as cancer,chronic fatigue syndrome,sleep disorder,senile dementia,and metabolic diseases,from the perspective of mitochondrial function.We aim to establish similarities and connections between two important concepts,and hope our essay can stimulate further discussion and investigation on unifying important concepts in western medicine and alternative medicine,especially TCM,and provide unique holistic insights into understanding human health.

When the Exotic Met the Erotic： The Representation of the Foreign in Ruyijun zhuan and ＂Jinhailing zongyu wangshen＂

Erotic fiction produced during the 16th and the early 17th centuries used different strategies to create settings for subversive sexual desires. This article examines one of these strategies： Authors of Ming erotic stories often associated the sexual expressions that challenged the existing social order with portrayals of the foreign. This article demonstrates that historical accounts and literary traditions informed the representations of the foreign in Ming erotic stories produced during the mid- and late Ming period through the examination ofRuyijun zhuan and ＂Jinhailing zongyu wangshen.＂ I argue that both narratives exoticized the erotic in order to exclude unsettling elements of sexual desire from China. However, due to their different views of sexual desire, they depicted the foreign differently. This paper concludes that the different strategies for appropriating sexual desire into foreign settings may be related to the historical contexts within which the two works of fiction were created.