Detecting intentional herding: what lies beneath intraday data in the spanish stock market

This paper examines the intentional herd behaviour of market participants using a new bootstrap-based approach that compares the scaled cross-sectional deviation of returns in the intraday market with the cross-sectional deviation of returns of an “artificially created” market free of intentional herding effects. The analysis is carried out for both the overall market and a sample of the most representative. The results show that the Spanish market exhibits a significant intraday herding effect that is not detected using other traditional measures when familiar stocks are analysed. Furthermore, it is suggested that herding is likely to be better revealed using intraday data.Behaviour, finance, time series

Identités de passage en Méditerranée au cours de l'ère moderne

Version pré-printL'emprunt d'une fausse identité peut être lié à une situation passagère, et l'imposture vouée à disparaître, ou bien construite pour durer, constituant les bases d'une nouvelle existence. Dans le cadre de la conflictualité maritime en Méditerranée durant l'ère moderne, l'usage d'identités d'emprunt a-t-il constitué un terrain d'imbrication entre Islam et Chrétienté ? L'espace maritime méditerranéen au XVIIe et au XVIIIe siècles offre un terrain de choix pour l'étude de la dissimulation. Les archives espagnoles se réfèrent à de nombreuses situations où " les usagers de la mer " camouflent, détournent ou usurpent des marques d'appartenance, des signes ou des indices identitaires. Stratégies offensives tout autant que défensives, ces techniques ne sont le monopole d'aucun belligérant, qu'il soit chrétien ou musulman

Differential sensitivity of Glioma stem cells to Aurora kinase A inhibitors: implications for stem cell mitosis and centrosome dynamics

Glioma stem-cell-like cells are considered to be responsible for treatment resistance and tumour recurrence following chemo-radiation in glioblastoma patients, but specific targets by which to kill the cancer stem cell population remain elusive. A characteristic feature of stem cells is their ability to undergo both symmetric and asymmetric cell divisions. In this study we have analysed specific features of glioma stem cell mitosis. We found that glioma stem cells appear to be highly prone to undergo aberrant cell division and polyploidization. Moreover, we discovered a pronounced change in the dynamic of mitotic centrosome maturation in these cells. Accordingly, glioma stem cell survival appeared to be strongly dependent on Aurora A activity. Unlike differentiated cells, glioma stem cells responded to moderate Aurora A inhibition with spindle defects, polyploidization and a dramatic increase in cellular senescence, and were selectively sensitive to Aurora A and Plk1 inhibitor treatment. Our study proposes inhibition of centrosomal kinases as a novel strategy to selectively target glioma stem cells

Hypoxia-inducible factor 1 alpha is required for the tumourigenic and aggressive phenotype associated with Rab25 expression in ovarian cancer

The small GTPase Rab25 has been functionally linked to tumour progression and aggressiveness in ovarian cancer and promotes invasion in three-dimensional environments. This type of migration has been shown to require the expression of the hypoxia-inducible factor 1 alpha (HIF-1α). In this report we demonstrate that Rab25 regulates HIF-1α protein expression in an oxygen independent manner in a panel of cancer cell lines. Regulation of HIF-1α protein expression by Rab25 did not require transcriptional upregulation, but was dependent on de novo protein synthesis through the Erbb2/ERK1/2 and p70S6K/mTOR pathways. Rab25 expression induced HIF-1 transcriptional activity, increased cisplatin resistance, and conferred intraperitoneal growth to the A2780 cell line in immunocompromised mice. Targeting HIF1 activity by silencing HIF-1β re-sensitised cells to cisplatin in vitro and reduced tumour formation of A2780-Rab25 expressing cells in vivo in a mouse ovarian peritoneal carcinomatosis model. Similar effects on cisplatin resistance in vitro and intraperitoneal tumourigenesis in vivo were obtained after HIF1b knockdown in the ovarian cancer cell line SKOV3, which expresses endogenous Rab25 and HIF-1α at atmospheric oxygen concentrations. Our results suggest that Rab25 tumourigenic potential and chemoresistance relies on HIF1 activity in aggressive and metastatic ovarian cancer. Targeting HIF-1 activity may potentially be effective either alone or in combination with standard chemotherapy for aggressive metastatic ovarian cancer

Utilizing Training and Educational Materials to Increase Hand Hygiene Compliance of Healthcare Providers Participating in Cesarean Sections

Surgical site infections (SSIs) are one of the most common complications of Cesarean section (C-section) procedures. The incidence of SSIs after C-section procedures at Hospital X has increased in each of the past three years. The Labor and Delivery (L&D) unit at Hospital X performs approximately 4,500 C-sections each year. Observation of these procedures illustrated a lack of adhesion to hand hygiene policies and protocols. This quality improvement project involved informing staff members of the poor hand hygiene compliance rates, and re-educating them regarding proper hand hygiene behavior using flyers, emails, and addressing them at shift change. Data collection focused on hand hygiene compliance among staff members involved in the C-section procedure. Staff members were observed entering and exiting the operating room to determine if they performed hand hygiene upon entry or exit. Hand hygiene compliance increased by 8.8% among all staff members. Obstetric (OB) nurse hand hygiene compliance increased by 28.6%. While overall hand hygiene compliance increased, it was not statistically significant; however, the increase in OB nurse compliance is statistically significant. Implementation of educating the OB nurses proved to be successful, and future interventions were recommended to continue to monitor and improve hand hygiene compliance

Henri Temianka Correspondence; (natividad)

https://digitalcommons.chapman.edu/temianka_correspondence/2520/thumbnail.jp

Role of SNARE Proteins in Natriuretic Peptide Secretion by the Heart

The hormones atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are stored and secreted by cardiac myocytes. To date, there is little information reported regarding the cellular mechanisms regulating the release of these hormones. Recent studies have identified soluble N-ethyl-maleimide-sensitive-fusion attachment protein receptors (SNAREs) in the trafficking, docking and fusion of ANP and BNP secretory vesicles. In this study, I characterized the expression profiles of the three SNARE proteins (syntaxin 5A, syntaxin 18, and SNAP29), implicated in constitutive exocytosis, in atrial and ventricular cardiac myocytes. My results suggest that syntaxin 5A, syntaxin 18 and SNAP29 are not important in the constitutive secretion of ANP and may play a role in another protein trafficking pathway. Syntaxin 1A and SNAP25, two SNARE proteins previously characterized in atrial cardiac myocytes, form a complex in adults that has been implicated in the exocytosis of ANP. I investigated the protein expression and promoter activity of these two SNARE proteins in neonatal and adult atrial and ventricular cardiac myocytes. The functional role of syntaxin 1A and SNAP25 was assessed using botulinum neurotoxin C (BoNT/C) and BoNT/A which cleave these SNARE proteins, respectively. Treatment of cardiac myocytes with BoNT/A and BoNT/C suggest that syntaxin 1A and SNAP25 regulate ANP secretion in neonatal cardiac myocytes, albeit low levels. Lastly, I examined the influence of forskolin and phorbol myristate acetate (PMA) on the syntaxin 1A and SNAP25 promoter. The lack of effect of these agents on gene reporter activity suggests that the CRE element in the syntaxin 1A and SNAP25 promoter do not significantly affect transcriptional activity. Overall, my studies demonstrate the developmental changes in SNARE protein expression in the heart, and their potential role in ANP secretion