Market trend, company size and microstructure characteristics of intraday stock price formations

The purpose of this study is to investigate whether there are certain price patterns during the trading session in the Athens Stock Exchange (ASE). We investigate statistically the series of stock returns, the volatility of stock returns and trading volume. In our analysis we use data from two different time periods; a period of rising prices (“bull” market) and a period of declining stock prices (“bear” market). We also use different categories of shares i.e. blue chips, medium capitalization stocks and small capitalization stocks. Our results indicate that there exist specific intraday patterns. The explanation of the revealed patterns can be based on investor sentiment and stock market microstructure characteristics.peer-reviewe

An investigation of price - volume intraday patterns under "Bull" and "Bear" market conditions

There has been a common belief among stock market practitioners that stock prices move along with trading volume creating certain patterns in price and volume formation. Nevertheless, the above argument was hardly recognised by the academic community since for a number of years statistical results indicated that the stock market is an efficient market i.e. a market where past available information is of no use in predicting future returns profitably, and/or non rational factors do not influence stock prices; The last decade the research for market efficiency was expanded and the use of new large data sets and advanced techniques indicated deviations from the predictions of the Efficient Market Hypothesis (E.M.H.). This study investigates whether there exists a relationship between stock returns and trading volume in the Athens Stock Exchange (A.S.E.) and if such a relationship forms evidence against the E.M.H. We believe that we add to the research in this area since we use intraday data and investigate for a possible relationship under different market states and for different categories of shares.peer-reviewe

Poisson-Schroedinger-Continuity two-dimensional analysis of both short (ballistic) and long (drift-diffusion) III-V FETs

It was recently shown that the quantum mechanical results of the Landauer theory of conduction, applied to a simple one-layer channel FET, can be recast in the traditional drift-diffusion form but with the mobility and injection velocity redefined in a new context. Based on that, we have performed two-dimensional Poisson-Schrödinger-Continuity calculations for both long drift-diffusion and short ballistic quantum well FETs. Very good agreement with many-layer, state-of-the-art InGaAs devices has been achieved provided that only one parameter, the saturation velocity υsat of the mobility function, is rescaled so that our calculated drain current agrees with the experimental value at very large gate voltages VG. This single value of υsat has been used at all other VG. Our calculations are not only a test of the equivalence described above but valuable information about the sub-threshold regime and especially the leakage currents is obtained. This information is usually absent in rigorous Landauer-type - or equivalently non-equilibrium Green's functions - calculations which are performed in simplified FET systems

Scale invariance of a diodelike tunnel junction

We measure the current vs voltage (I-V) characteristics of a diodelike tunnel junction consisting of a sharp metallic tip placed at a variable distance d from a planar collector and emitting electrons via electric-field assisted emission. All curves collapse onto one single graph when I is plotted as a function of the single scaling variable Vd^{-\lambda}, d being varied from a few mm to a few nm, i.e., by about six orders of magnitude. We provide an argument that finds the exponent {\lambda} within the singular behavior inherent to the electrostatics of a sharp tip. A simulation of the tunneling barrier for a realistic tip reproduces both the scaling behavior and the small but significant deviations from scaling observed experimentally.Comment: 6 pages, 6 figures. Accepted for publication in Physical Review

Prognostic stratification of patients with advanced renal cell carcinoma treated with sunitinib: comparison with the Memorial Sloan-Kettering prognostic factors model

<p>Abstract</p> <p>Background</p> <p>The treatment paradigm in advanced renal cell carcinoma (RCC) has changed in the recent years. Sunitinib has been established as a new standard for first-line therapy. We studied the prognostic significance of baseline characteristics and we compared the risk stratification with the established Memorial Sloan Kettering Cancer Center (MSKCC) model.</p> <p>Methods</p> <p>This is a retrospective analysis of patients treated in six Greek Oncology Units of HECOG. Inclusion criteria were: advanced renal cell carcinoma not amenable to surgery and treatment with Sunitinib. Previous cytokine therapy but no targeted agents were allowed. Overall survival (OS) was the major end point. Significance of prognostic factors was evaluated with multivariate cox regression analysis. A model was developed to stratify patients according to risk.</p> <p>Results</p> <p>One hundred and nine patients were included. Median follow up has been 15.8 months and median OS 17.1 months (95% CI: 13.7-20.6). Time from diagnosis to the start of Sunitinib (<= 12 months vs. >12 months, p = 0.001), number of metastatic sites (1 vs. >1, p = 0.003) and performance status (PS) (<= 1 vs >1, p = 0.001) were independently associated with OS. Stratification in two risk groups ("low" risk: 0 or 1 risk factors; "high" risk: 2 or 3 risk factors) resulted in distinctly different OS (median not reached [NR] vs. 10.8 [95% confidence interval (CI): 8.3-13.3], p < 0.001). The application of the MSKCC risk criteria resulted in stratification into 3 groups (low and intermediate and poor risk) with distinctly different prognosis underlying its validity. Nevertheless, MSKCC model did not show an improved prognostic performance over the model developed by this analysis.</p> <p>Conclusions</p> <p>Studies on risk stratification of patients with advanced RCC treated with targeted therapies are warranted. Our results suggest that a simpler than the MSKCC model can be developed. Such models should be further validated.</p

Development and Validation of Risk Prediction Models for Cardiovascular Events in Black Adults: The Jackson Heart Study Cohort

Cardiovascular risk assessment is a fundamental component of prevention of cardiovascular disease (CVD). However, commonly used prediction models have been formulated in primarily or exclusively white populations. Whether risk assessment in black adults is dissimilar to that in white adults is uncertain

Potential value of PTEN in predicting cetuximab response in colorectal cancer: An exploratory study

<p>Abstract</p> <p>Background</p> <p>The epidermal growth factor receptor (EGFR) is over-expressed in 70–75% of colorectal adenocarcinomas (CRC). The anti-EGFR monoclonal antibody cetuximab has been approved for the treatment of metastatic CRC, however tumor response to cetuximab has not been found to be associated with EGFR over-expression by immunohistochemistry (IHC). The aim of this study was to explore EGFR and the downstream effector phosphatase and tensin homologue deleted on chromosome 10 (PTEN) as potential predictors of response to cetuximab.</p> <p>Methods</p> <p>CRC patients treated with cetuximab by the Hellenic Cooperative Oncology group, whose formalin-fixed paraffin-embedded tumor tissue was available, were included. Tissue was tested for EGFR and PTEN by IHC and fluorescence in situ hybridization (FISH).</p> <p>Results</p> <p>Eighty-eight patients were identified and 72 were included based on the availability of tissue blocks with adequate material for analysis on them. All patients, except one, received cetuximab in combination with chemotherapy. Median follow-up was 53 months from diagnosis and 17 months from cetuximab initiation. At the time of the analysis 53% of the patients had died. Best response was complete response in one and partial response in 23 patients. In 16 patients disease stabilized. Lack of PTEN gene amplification was associated with more responses to cetuximab and longer time to progression (p = 0.042).</p> <p>Conclusion</p> <p>PTEN could be one of the molecular determinants of cetuximab response. Due to the heterogeneity of the population and the retrospective nature of the study, our results are hypothesis generating and should be approached with caution. Further prospective studies are needed to validate this finding.</p

Demographic and Clinical Factors Associated With SARS-CoV-2 Spike 1 Antibody Response Among Vaccinated US Adults: the C4R Study

This study investigates correlates of anti-S1 antibody response following COVID-19 vaccination in a U.S. population-based meta-cohort of adults participating in longstanding NIH-funded cohort studies. Anti-S1 antibodies were measured from dried blood spots collected between February 2021-August 2022 using Luminex-based microsphere immunoassays. Of 6245 participants, mean age was 73 years (range, 21-100), 58% were female, and 76% were non-Hispanic White. Nearly 52% of participants received the BNT162b2 vaccine and 48% received the mRNA-1273 vaccine. Lower anti-S1 antibody levels are associated with age of 65 years or older, male sex, higher body mass index, smoking, diabetes, COPD and receipt of BNT16b2 vaccine (vs mRNA-1273). Participants with a prior infection, particularly those with a history of hospitalized illness, have higher anti-S1 antibody levels. These results suggest that adults with certain socio-demographic and clinical characteristics may have less robust antibody responses to COVID-19 vaccination and could be prioritized for more frequent re-vaccination