The geography of Canadian interlocking directorates: how do they relate to brain circulation?

This study examines the spatiality of interlocking directorates of Canadian companies, with particular emphasis given to international interlocks. From a geographical standpoint, do these connections to foreign firms reinforce the importance of Canada’s top corporate cities as ‘gateways’ to international business? Is there a geography associated with the interlocking to these gateway cities? Findings build on James O. Wheeler’s body of research focused on corporate headquarters. This study is placed within the context of the current economic geography dialogue. Particular focus is placed on Saxenian’s theory of brain circulation, wherein she argues that individuals with international experience serve as brokers linking domestic businesses with those in distant regions. A further purpose of this study then is to examine Saxenian’s argument in the context of Canadian corporations. First, is there a geographical association between directors’ foreign educations and where Canadian firms are interlocked to internationally? Second, the corporate performance of Canadian firms interlocked internationally will be measured against those firms that are not. It seems logical to assume that increased connections would yield more diverse and rich knowledge, which could lead to better decisions, and thus corporate performance, in today’s global world. But does it? This study finds that being linked to an international company through a common director did translate into more profitability for Canadian firms. Findings also revealed a geographical link between international interlocks and a director’s foreign education. However, when Canadian firms were interlocked with an international company with a director who had international education, greater profits did not necessarily result.     

益气活血方对射血分数保留型心力衰竭患者血清BNP、hs-CRP及心功能的影响

目的：观察益气活血方对射血分数保留型心力衰竭（HFpEF）患者进行干预后,其心功能、脑钠肽（BNP）、超敏C反应蛋白（hs-CRP）的变化情况。方法：将84 例HFpEF患者按照随机数字表法分为治疗组和对照组,每组各42 例。对照组采用西医标准化治疗方案,治疗组在对照组基础上给予益气活血方治疗,2组疗程均为4周。观察2组治疗前后心功能指标［包括心室收缩末期内径（LVESD）、左心室舒张末期内径（LVEDD）、左室射血分数（LVEF）、6 min步行试验（6MWT）］、BNP及hs-CRP的变化,并评价综合疗效。结果：总有效率治疗组为90.48%（38/42）,对照组为80.95%（34/42）,2组比较,差异有统计学意义（P＜0.05）。治疗后2组LVESD、LVEDD及血清BNP、hs-CRP水平均较治疗前降低,LVEF较治疗前升高,6MWT较治疗前增加,且治疗组各项指标改善情况均优于对照组,差异均有统计学意义（P＜0.05）。结论：益气活血方能够抑制HFpEF患者体内BNP和hs-CRP的表达,改善心功能指标,增加6MWT距离。     

二、三倍体牙鲆肌肉和脑组织实时定量PCR内参基因的筛选及鉴定

多倍体诱导会造成物种中不同基因的表达水平变化不同,以内参基因作为对照的相对实时定量PCR是检测基因表达水平变化的一种高效方法,这就需要对多倍体中的内参基因进行筛选以获得较适宜的参比基因.本研究以二倍体和三倍体牙鲆肌肉和脑组织为对象,以绝对定量及2-ΔCt等方法分析管家基因18S rRNA、β-肌动蛋白基因(β-acti...     

头颅CT造影增强扫描技术临床应用价值

目的 探讨头颅CT增强造影扫描技术在临床应用价值。材料与方法 着重分析48例病例在CT造影增强扫描后的影像表现。结果 病灶均匀一致性强化8袋子例，环状强化9例，点状强化7例，结节状强化12例，不规则强化7例，强化不明显5例，脑膜或小脑幕强化结构清晰38例。结论 头颅CT增强造影扫描能够提高病变的密度分辨力，有利于明确病变的定位和定性，为临床提供更多的重要信息。     

Relationships between ultrapotassic and carbonate-rich volcanic rocks in central Italy: petrogenetic and geodynamic implications

The Pleistocene intra-Apennine volcanic (IAV) centres occurring east of the potassium-rich Roman comagmatic province show variable petrological and geochemical composition. Some rocks have a strongly undersaturated ultrapotassic kamafugitic affinity with K₂O/Na₂O=8–20, whereas the rocks from the southern center of Mt. Vulture are still strongly undersaturated in silica but are enriched in both Na₂O and K₂O with K/Na around unity. Carbonate-rich pyroclastic rocks, believed to represent carbonatitic magmas, are found in the IAV centers. Kamafugites have high abundances of LILE and high LILE/HFSE ratios, and their incompatible element patterns resemble closely those of ultrapotassic rocks from the adjoining Roman province. The Vulture volcanics also display high contents of LILE, but their LILE/HFSE ratios are intermediate between intraplate alkaline rocks and kamafugites. The carbonate-rich rocks exhibit an exotic mineralogy and high enrichments in LILE, which speaks for a carbonatitic affinity. However, they have similar incompatible element patterns but consistently lower abundances of almost all the elements than the associated silicate volcanics. These data favour the hypothesis that the IAV carbonate rocks may represent mixtures of silicate magmas and geochemically depleted carbonate material. The sedimentary carbonates that crop out extensively along the Apennine chain may be the source of barren carbonate material. Overall, geochemical data of IAV centres and of the rocks from the Roman province display strong geochemical and isotopic evidence of being generated in an upper mantle that was modified by addition of upper crustal material brought down by subduction processes. A possible exception is represented by Mt. Vulture which, however, occurs east of the main axis of the Apennines, on the western margin of the foreland Adria plate. The occurrence of strongly undersaturated alkaline rocks requires magma generation at high pressures and . This is in agreement with the hypothesis that subduction processes under the Apennines occurred by consumption of poorly hydrated thinned or delaminated continental crust.     

从测绘学到地球空间信息智能服务科学

回顾了从传统测绘学到当今地球空间信息智能服务科学的60年发展历程;总结了测绘学从模拟到解析再到数字化发展的3个重要阶段;介绍了GNSS、RS与GIS(3S)集成,从而形成了地球空间信息学的兴起;分析了数字地球时代地球空间信息学的发展,进而论述了当今智慧地球时代地球空间信息科学走向实时智能服务的最新进展,并对"互联网+"空间信息智能服务的3个发展水平进行了重点论述。可以肯定,在大数据时代传统的测绘学必将集通信、导航、遥感、人工智能、虚拟现实和脑认知科学之大成,发展成为地球空间信息智能服务科学,为富国强军与利民作出应有的贡献。     

牙鲆gnrh基因的表达分析

本文通过qPCR方法,研究了我国重要海水鱼类——牙鲆（Paralichthys olivaceus）雌、雄成体组织以及性腺分化期的脑、性腺中gnrh1、gnrh2和gnrh3的表达水平。结果显示,gnrh1分布于所有检测的组织：在脑、垂体、肾脏和肝脏中高表达,在性腺中表达相对较低;gnrh2则在雌、雄性的肝脏以及雄性的肠、肾脏、眼睛和头肾中;而gnrh3只在雄性的肾脏、眼睛和肌肉中检测到微弱表达。人工诱导的牙鲆雌核发育鱼苗分别用17β-雌二醇（E₂）和17α-甲基睾酮（MT）处理,使其分化为雌性或雄性个体表型。在性腺分化期的脑中,gnrh1的表达呈现上升趋势,在全长（total length,TL）4 cm鱼苗中,E₂组的表达显著高于MT组（P<0.05）;gnrh2在2 cm TL时E₂组显著高于MT组（P<0.05）,随后在E₂和对照组的表达水平均出现下降趋势;gnrh3在2 cm TL时E₂和对照组的表达均显著高于MT组（P<0.05）,自6 cm TL时MT和E₂组的表达开始下降。在性腺中,三种gnrh在性腺分化前2 cm TL表达量都相对较高,随后呈现下降趋势。综上,推测牙鲆gnrh1可能参与了性腺分化的启动、分化过程及性腺发育,gnrh2主要参与了性腺分化的启动,gnrh3主要参与了性腺分化的启动和分化过程。     

MSCTA在颅内动脉瘤诊断中的应用

目的：探讨多层螺旋CT血管成像在颅内动脉瘤的诊断中的应用。方法：收集经手术证实或DSA的颅内动脉瘤31例,所有的病例均行多层螺旋CT血管成像。CTA通过采取VR、MIP及CPR等后处理重建技术,实现脑内血管重现,展现颅内血管的真实情况。20例行手术治疗,11例行DSA检查。结果：本组31例,共36个颅内动脉瘤。29例单...     

Morphological and histological changes in the brains of turbot (Scophthalmus maximus) with gonadal development

The brain plays a critical role in controlling reproduction through the hypothalamus-pituitary-gonadal (HPG) axis in vertebrates. Turbot (Scophthalmus maximus) has become an economically important marine fish in Europe and North China. Previous research investigating turbot reproduction has focused on the role of the HPG axis in regulating egg and sperm production. However, the morphology and histology of the organs in the HPG axis have not been studied. In this study, we investigated the morphology and histology of brains in female and male turbot at different stages of gonadal development. The results showed that the brains of both female and male turbot were composed of seven parts that are typical of advanced teleosts: the telencephalon, diencephalon, cerebellum, hypothalamus, pituitary gland, myelencephalon, and olfactory bulbs. The telencephalon was well-developed and contained five distinct lobes, with the contiguous diencephalon at the caudal portion. The torus longitudinales and rostral torus semicircularis of the mesencephalon flattened along the dorsal surface, and the rostral corpus cerebellum was located in the dorsal portion. The actual total brain volume in mature males was significantly greater (p<0.05) than that of females with gonadal development. Notably, the pituitary volume in male turbot significantly increased (p<0.05) from immature to mature stage, but this difference did not occur in females. The data together illustrate a distinct sex difference in the turbot brain during gonadal development, providing insight into their HPG axes.     

Identification and distribution of gonadotropin-releasing hormone-like peptides in the brain of horseshoe crab Tachypleus tridentatus

Gonadotropin-releasing hormone(GnRH) is a crucial peptide for the regulation of reproduction.Using immunological techniques,we investigated the presence of GnRH in horseshoe crab Tachypleus tridentatus.Octopus GnRH-like immunoreactivity,tunicate GnRH-like immunoreactivity,and lamprey GnRH-like immunoreactivity were detected in the neurons and fibers of the protocerebrum.However,no mammal GnRH-like immunoreactivity or lamprey GnRH-Ш-like immunoreactivity was observed.Our results suggest that a GnRH-like factor,an ancient peptide,existed in the brain of T.tridentatus and may be involved in the reproductive endocrine system.