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Using proprietary account-level transaction data in the futures market where day traders are self-declared ex ante, this study investigates whether day traders enhance price discovery at the market level. From a natural classification of day traders, we find that heterogeneous day traders have differential effects on price discovery. Self-declared day traders, who benefit from low margin requirement, do not improve price discovery measured by information share. In contrast, non-declared traders, who are not self-declared as day traders, improve price discovery. Their positive impacts on price discovery are particularly significant during periods of high volatility and arrival of new information. Overall, a margin stimulating policy may encourage more day trading, but may also attract overconfident investors, especially inexperienced ones, and who do not enhance price discovery.

It had not been reported that myocardial scar shown on gated myocardial perfusion SPECT (GMPS) might reduce after cardiac resynchronization therapy (CRT). In this study, we aim to investigate the clinical impact and characteristic of scar reduction (SR) after CRT. Sixty-one heart failure patients following standard indication for CRT received twice GMPS as pre- and post-CRT evaluations. The patients with an absolute reduction of scar ≥ 10% after CRT were classified as the SR group while the rest were classified as the non-SR group. The SR group (N = 22, 36%) showed more improvement on LV function (∆LVEF: 18.1 ± 12.4 vs 9.4 ± 9.9 %, P = 0.007, ∆ESV: − 91.6 ± 52.6 vs − 38.1 ± 46.5 mL, P < 0.001) and dyssynchrony (ΔPSD: − 26.19 ± 18.42 vs − 5.8 ± 23.0°, P < 0.001, Δ BW: − 128.7 ± 82.8 vs − 25.2 ± 109.0°, P < 0.001) than non-SR group (N = 39, 64%). Multivariate logistic regression analysis showed baseline QRSd (95% CI 1.019-1.100, P = 0.006) and pre-CRT Reduced Wall Thickening (RWT) (95% CI 1.016-1.173, P = 0.028) were independent predictors for the development of SR. More than one third of patients showed SR after CRT who had more post-CRT improvement on LV function and dyssynchrony than those without SR. Wider QRSd and higher RWT before CRT were related to the development of SR after CRT.

Background 18F-FDG PET/CT has been wildly used in cancer screening. However, FDG accumulates not only in malignant lesions but also in inflammatory processes, which are frequently observed in normal subjects. We investigated PET/CT images in healthy subjects and identified the correlation between quantitative values of images and clinical characteristics. Method 105 subjects undergoing PET/CT scans for health examinations were retrospectively collected. The standardized uptake value (SUVmax) in the nasopharyngeal (NP) region, neck lymph nodes (LNs), palatine tonsil, mediastinal or pulmonary LNs were evaluated. The correlation between the SUVmax and the clinical variables was assessed. Results There is strong negative correlation between the SUVmax of palatine tonsils and age (p =0.0004), strong positive correlation between the SUVmax of mediastinal LNs and age (p =0.0004). There’s positive correlation between the SUVmax of palatine tonsils and cholesterol (p =0.03), the SUVmax of neck LNs and serum CRP level (p = 0.04). Conclusion Age may have different effect on SUVmax of palatine tonsils and mediastinal LNs. While serum level of Cholesterol and CRP may be related to higher FDG uptake. Understanding clinical characteristics of subjects may help the interpretation of PET/CT images for cancer screening.

Background F-18 Fluorodeoxyglucose positron emission tomography with computed tomography (FDG PET/CT) is a powerful tool in oral cancer. However, the oral cavity is a small cavity with complex components. An invasive cancer or post-therapy change frequently cause difficulty in interpretation. In this study, we established a tongue depressor (TD)-assisted FDG PET/CT protocol to solve this problem. Methods We enrolled 264 patients with oral cancers. Early and delayed images were acquired in each FDG PET/CT examination. A wooden tongue depressor was placed either between buccal mucosa and teeth or between tongue border and teeth in delayed image. TD placed delayed image was compared with early images to analyze the extent of tumor. The discrimination ratio (DR) of the tumor was calculated as: (images that can clearly distinguish features /all images) × 100%. Results In tongue cancer group, the DR of the tumors were 26.1% on early images and 99.3% on TD placed delayed images (p

Background and purpose: Histone deacetylase (HDAC) inhibitors (HDIs) were shown to modulate the epithelial-mesenchymal transition (EMT) progression and inhibit the migration and invasion of cancer cells. Emerging as a novel class of anti-cancer drugs, HDIs have attracted much attention in the field of drug discovery. This study aimed to the underlying mechanisms of Honokiol in preventing the metastatic dissemination of gastric cancer cells by inhibiting HDAC3 activity/expression.Experimental Approach: Clinical pathological analysis was performed to determine the relationship between HDAC3 and tumor progression. The effects of Honokiol on pharmacological characterization, functional, transcriptional activities, organelle structure changes, and molecular signalings were analyzed using binding assays, Differential Scanning Calorimetry, luciferase reporter assay, HDAC3 activity, ER stress response element activity, transmission electron microscopy, immune-blotting and Wnt/b-catenin activity assays. The in vivo effects of Honokiol on peritoneal dissemination were determined by a mouse model and detected by the PET/CT tomography.Key Results: HDAC3 over-expression was correlated with poor prognosis. Honokiol significantly abolished HDAC3 activity (Y298) via inhibition of NFκBp65/CEBPb signaling, which was reversed by the over-expression of plasmids of NFκBp65/CEBPb. Honokiol-inhibited NFκBp65/CEBPb activation could be reversed by 4-phenylbutyric acid (a chemical chaperone) and calpain-2 gene silencing. Honokiol increased ER stress markers and inhibited EMT-associated epithelial markers, but decreased Wnt/β-catenin activity. Suppression of HDAC3 by both Honokiol and HDAC3 gene silencing decreased cell migration and invasion in vitro and metastasis in vivo. Conclusions and Implications: Honokiol acts by suppressing HDAC3-mediated EMT and metastatic signaling. By prohibiting HDAC3, metastatic dissemination of gastric cancer may be blocked.

Background and purpose Histone deacetylase (HDAC) inhibitors (HDIs) can modulate the epithelial-mesenchymal transition (EMT) progression and inhibit the migration and invasion of cancer cells. Emerging as a novel class of anti-cancer drugs, HDIs are attracted much attention in the field of drug discovery. This study aimed to discern the underlying mechanisms of Honokiol in preventing the metastatic dissemination of gastric cancer cells by inhibiting HDAC3 activity/expression. Experimental approach Clinical pathological analysis was performed to determine the relationship between HDAC3 and tumor progression. The effects of Honokiol on pharmacological characterization, functional, transcriptional activities, organelle structure changes, and molecular signaling were analyzed using binding assays, differential scanning calorimetry, luciferase reporter assay, HDAC3 activity, ER stress response element activity, transmission electron microscopy, immune-blotting, and Wnt/β-catenin activity assays. The in vivo effects of Honokiol on peritoneal dissemination were determined by a mouse model and detected by PET/CT tomography. Key results HDAC3 over-expression was correlated with poor prognosis. Honokiol significantly abolished HDAC3 activity (Y298) via inhibition of NFκBp65/CEBPβ signaling, which could be reversed by the over-expression of plasmids of NFκBp65/CEBPβ. Treatments with 4-phenylbutyric acid (a chemical chaperone) and calpain-2 gene silencing inhibited Honokiol-inhibited NFκBp65/CEBPβ activation. Honokiol increased ER stress markers and inhibited EMT-associated epithelial markers, but decreased Wnt/β-catenin activity. Suppression of HDAC3 by both Honokiol and HDAC3 gene silencing decreased cell migration and invasion in vitro and metastasis in vivo. Conclusions and implications Honokiol acts by suppressing HDAC3-mediated EMT and metastatic signaling. By prohibiting HDAC3, metastatic dissemination of gastric cancer may be blocked. Graphical abstract Conceptual model showing the working hypothesis on the interaction among Honokiol, HDAC3, and ER stress in the peritoneal dissemination of gastric cancer. Honokiol targeting HDAC3 by ER stress cascade and mitigating the peritoneal spread of gastric cancer. Honokiol-induced ER stress–activated calpain activity targeted HDAC3 and blocked Tyr298 phosphorylation, subsequently blocked cooperating with EMT transcription factors and cancer progression. The present study provides evidence to demonstrate that HDAC3 is a positive regulator of EMT and metastatic growth of gastric cancer cells. The findings here imply that overexpressed HDAC3 is a potential therapeutic target for honokiol to reverse EMT and prevent gastric cancer migration, invasion, and metastatic dissemination. • Honokiol significantly abolished HDAC3 activity on catalytic tyrosine 298 residue site. In addition, Honokiol-induced ER stress markedly inhibited HDAC3 expression via inhibition of NFκBp65/CEBPβ signaling. • HDAC3, which is a positive regulator of metastatic gastric cancer cell growth, can be significantly inhibited by Honokiol. • Opportunities for HDAC3 inhibition may be a potential therapeutic target for preventing gastric cancer metastatic dissemination.

Transthyretin cardiac amyloidosis (ATTR-CM) is an increasingly recognized cause of heart failure with preserved ejection fraction. Favorable prognosis depends on early diagnosis and correct treatment strategy. Among patients for whom there is a high clinical suspicion of cardiac amyloidosis, (99m)Tc-labeled bone avid scintigraphy including (99m)Tc-pyrophosphate (PYP) scintigraphy may be of diagnostic and prognostic importance. Various international guidelines support the non-biopsy diagnosis of ATTR-CM using (99m)Tc-PYP scintigraphy, yet emphasize the gap in standardization of acquisition and imaging analysis protocols, as well as the appropriateness of its clinical use. Therefore, a joint expert consensus has been reached by the Taiwan Society of Cardiology and the Society of Nuclear Medicine of the Republic of China, to advocate for the application of (99m)Tc-PYP scintigraphy in the diagnosis of ATTR-CM. This article aims to highlight the recommendations on image acquisition, qualitative and quantitative assessments of cardiac (99m)Tc-PYP uptake, and diagnostic algorithms. We hope the implementation of these recommendations in Taiwan will facilitate the process and enhance the diagnostic rate of ATTR-CM.

Gated myocardial perfusion SPECT (GMPS) provides a one-stop-shop evaluation for cardiac resynchronization therapy (CRT). However, conflicting results have been observed regarding whether the baseline left-ventricular (LV) mechanical dyssynchrony as assessed by phase analysis on GMPS was predictive of therapeutic response to CRT. Since dyssynchrony parameters by phase analysis spuriously increased by scarred myocardium, the purpose of this study was to explore the value of dyssynchrony after stripping off the scar region in correlation to mechanical response to CRT. Forty-seven patients following standard indications for CRT received GMPS with phase analysis as pre-CRT evaluation. A decrease of end-systolic volume (ESV) > 15% on follow-up echocardiography after CRT was considered as a mechanical response to CRT. Myocardial regions with less than 50% of maximal activity on GMPS were considered as a scar. The phase standard deviation (PSD) and histogram bandwidth (BW) without or with stripping off scar were assessed by phase analysis of GMPS and were used for evaluation of LV dyssynchrony of all myocardium or only the viable myocardium, respectively. No significant difference was noted between mechanical responders (31 of 47 patients, 66%) and nonresponders ( 16 of 47 patients, 34%) for PSD (48.6° ± 19.4° vs 43.9° ± 20.7°, p = 0.46) and BW (225° ± 91.1° vs 163.5° ± 94.6°, p = 0.38) of the entire myocardium. However, responders had significantly larger PSD (40.5° ± 15.7° vs 30.5° ± 13.2°, p = 0.03) and borderlinely larger BW (215° ± 91.2° vs. 139.5° ± 78.2°, p = 0.05) than non-responders after stripping off scar. Logistic regression analysis showed that scar area and PSD after stripping off scar were independent predictors of mechanical response. Our result showed that LV dyssynchrony of the entire myocardium did not predict response to CRT. However, LV dyssynchrony only in the viable myocardium was a significant predictor of CRT mechanical response.

This paper studies how to retrieve aggregate information from the trading volume of Taiwan composite stock index options (TXO) with better quality by modifying the two option-information aggregation methods introduced in Holowczak et al. (2014). To study an emerging market such as the Taiwan options market, whose major players are retail investors, we take into consideration the retail participation rate and the trading distribution across moneyness, in addition to factors such as option market depth, liquidity, and investors' trading purposes, as discussed in Holowczak et al. (2014). Retail investors, who are generally less well-informed, have traded mainly nearby TXO options with expirations of less than one month. Therefore, the weights of nearby contracts should be reduced. Furthermore, both institutions and retail investors have traded more at near-the-money TXO options, and consequently the weights of in-the-money options and out-of-the-money options should be discounted to accommodate the uneven option trading across moneyness. In addition, we find that there is a dichotomy in the information roles of out-of-the-money options: the information content of their trades is higher (lower) when market volatility increases (decreases). Based on this finding, we establish a VIX-adjusted put-call ratio which increases (decreases) the weight of out-of-the-money options when the market VIX is larger (smaller) than its previous average level. Our model, as revised for an emerging market such as the Taiwan options market, has outperformed in explaining contemporaneous price changes and has shown very good predictive ability for large downside market moves.

Using account-level transaction data in options and futures markets, we investigate the existence of market manipulation, which is the ability of large traders to trade strategically, impacting prices and making abnormal profits. First, large trader’s option positions have a quantity impact on the underlying asset’s price. Second, large traders generate significantly positive alphas from trading options and futures. Among the different investor types, proprietary dealers generate the largest positive alphas. Third, these abnormal returns are consistent with strategic trading and cross-market manipulation. The evidence supports market manipulation across the options and futures markets, but not within the futures market itself.

We analyze the complete tick-level stock trading records at the Taiwan Stock Exchange and explore what factors are principally associated with stock price jumps in high frequency. Among the potential candidate variables suggested in the literature, liquidity proxies appear to be primarily associated with signed jumps in high frequency. The results from the least absolute shrinkage and selection operator (LASSO), the elastic net method, and principal component analysis further show that liquidity issues are more important than information or sentiment in understanding sudden and discontinuous price innovations to financial assets in high frequency.

Our study tries to propose a method that can rapidly process and calibrate data sets through our previous dynamic programming (DP) tool, manually adjust error-heavy labels, and then train neural network models to accurately segment gated SPECT MPI images. Lastly, LV contours can be accurately determined on the gated SPECT MPI images and corresponding LV volumes can also be evaluated. First, we used our previous DP-based tool to coarsely determine the myocardial profiles on SPECT MPI images. In order to obtain a more accurate LV volumes and LVEF, it was also necessary to manually adjust the profiles that do not meet the clinical requirements. Then the results of manual adjustment were used as the ground truths to train the end-to-end full convolution neural networks by deep learning (DL). The method proposed in this paper was evaluated with the Dice similarity coefficient and Hausdorff distance, and the results showed that the proposed method had a high similarity with the ground truth. The LV volumes and LVEFs estimated by different methods were calculated separately and compared each other, and the experimental results showed that the performance of the proposed DL-based method was superior to that of the DP-based method and close to that of QGS program. As a quantitative analysis tool, the proposed DL-based method is fully automatic and more accurate in the evaluation of LV volumes and LVEFs, so it is expected that the DL-based method may have a wide application prospect in clinical practices.

This paper studies the presence of informed trading in Taiwan stock index options (TXO) and analyzes the informational role of foreign institutions in incorporating information into Taiwan stock index futures (TX). We have found that only the option-induced part (OOI) of the total TX order imbalance can predict future TX prices, and the OOI calculated from open-buy TXO, defined by Ni et al. (2008), provides incremental predictability. This finding shows that the price predictability stems from the information flow resulting from option transactions rather than from liquidity pressure. We conclude further that option transactions from foreign institutions provide the most significant predictability, out-of-the-money option transactions in particular. These empirical results show that option transactions conducted by foreign institutions have played the primary role in conveying the information inherent in the TXO market to the TX market, foreign institutions being delta-informed traders. Retail investors, the major players in both the TXO and TX markets, have done almost nothing of significance with regard to TXO information transmission into the TX market, with the exception of some near-the-money and out-of-the-money options.

This study recalibrates corporate bond idiosyncratic risks in an international context. By applying a statistically powerful risk decomposition scheme, the authors show that diversification is significantly improved by the addition of a global risk benchmark. They construct a long-run stationary yield spread decomposition scheme that further provides a better diversification effect. In addition to global liquidity and default risk factors, a country-specific default risk component is included, and all of them are free of measurement or availability issues. The idiosyncratic risk component is estimated as a fixed effect along with all the parameter estimates, rather than separately from an exogenous generating process. The linear model is simple, yet it can be easily and promptly applied by practitioners.

There is increasing global incidence of highly metastatic melanoma and therapeutic strategies like those focusing on the downstream beta-catenin/MITF axis of invading melanoma cells are urgently needed. Targeting endoplasmic reticulum (ER) stress can promote cancer cell death and inhibit epithelial mesenchymal transition (EMT) in metastatic tumors. This study aimed to determine if Honokiol could promote ER stress-dependent apoptosis and regulate metastatic melanoma. The therapeutic efficacy of Honokiol was assessed using the highly metastatic melanoma xenograft mouse model for peritoneal metastasis and evaluated by computed tomography imaging. The ER stress marker, Calpain-10, delineated a novel proteolytic cleavage enzyme, while CHOP/GADD153-regulated apoptosis was used for gene silencing to determine the role of the β-catenin/MITF axis in melanoma cells. The results showed that Honokiol effectively decreased peritoneal dissemination and organ metastasis via ER stress activation and EMT marker inhibition. Knockdown Calpain-10 or CHOP/GADD153 blocked all of the biological effects in Honokiol-induced β-catenin/MITF cleavage, ERSE or TCF/LEF luciferase activity, and β-catenin kinase activity. These findings suggest that Honokiol can significantly thwart the progression of highly metastatic melanoma using the β-catenin/MITF axis via prompt Calpain-10 and CHOP/GADD153 regulated cascades.

This paper investigates comparative information advantage for foreign and domestic institutions on Taiwan's index options by examining the intraday information content of limit orders placed by foreign and domestic institutions, respectively. The height and length of limit order book provided by either foreign or domestic institutions exhibit predictive power on subsequent price changes in options, especially for put options. The information advantage is more significant for foreign institutions with respect to both call and put options. On the other hand, the results are mixed when order imbalance is used as the proxy of information on limit order book. Foreign institutions outperform domestic institutions for put options, not call options. Order imbalance, ignoring differential aggressiveness of limit orders, fails to capture comparative information advantage for foreign institutions. The superior information advantage for foreign institutions persists during the financial tsunami of 2008–2009 and periods of substantial price changes.

This study provides a theoretical model and empirical analysis to jointly examine the information, financing and agency effects, the three channels through which the stock market can actively influence corporate investment decisions and firm performance. First, stock market affects corporate investments, and such impact varies with different market valuation measures, types of investments and firm characteristics. Second, stock market valuation affects investments through the channel of corporate financing, supporting the financing hypothesis. Third, stock market-driven investments have differential impacts on the future operating performance of firms. Investments driven by market valuation of firm-specific information have a positive effect on future performance. In contrast, investments driven by market-wide sentiment have a negative effect on future performance. Fourth, consistent with the information hypothesis, market-driven investments are value-enhancing for firms with better external monitoring by...

This paper investigates the relationship between individuals’ net trading and stock price movements before and after annual earnings announcements for the Taiwan Stock Exchange. We conduct an event study on the effects of pre-event individual trade imbalances on pre- and post-announcement abnormal returns. With a unique and comprehensive dataset, we accurately classify executed orders by aggressiveness of order price. The evidence indicates that while individuals, as a group, are not informed about impending earnings announcements, individuals who place aggressive orders are informed as their net trading coincides with contemporaneous and future stock returns. Aggressive individuals lose their edge during the financial crisis. More importantly, the advantage (disadvantage) for individuals who adopt aggressive (passive) orders weakens when foreign institutions own concentrated equity in firms. We also find that net individual trading contains information about abnormal returns that either past returns or volume does not subsume. Controlling for past returns, trading volume and volatility, or using an alternative measure of net individual trading does not change our conclusions.

This paper investigates the role of liquidity provisions played by individual investors prior to dividend announcements in Taiwan. We first document a positive relationship between aggregate individual trading before dividend announcements and abnormal stock returns in the one month after the events. We find that this positive relationship varies with liquidity. We then decompose the abnormal returns following the event into information and liquidity provision components. The information component is not significant at all, but the liquidity component is positively significant, which shows that it is individual investors’ provisions of liquidity to institutional investors prior to dividend announcements that drives the positive relationship between pre-event individual trading and post-event returns.

Biokinetic model of Tc-99m MIBI for eight patients undergone myocardial perfusion examination was studied using gamma camera and MATLAB program. A six-compartment model was adopted to interpret the metabolic mechanism of each patient. Within the model framework, the respective set of simultaneous differential equations was solved by a self-developed program run in MATLAB. The experimental results exhibited a good fit with the theoretical predictions via the model. The average biological half-lives of body fluid, heart, thyroid, liver, GI Tract and remainder were assessed as [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text][Formula: see text]h, respectively. A dimensionless AT index of disagreement between the experimental data and MATLAB optimal solution was proposed of validating the applied acquisition system and analytical method feasibility. An AT of zero implies a perfect agreement between the theoretical and empirical results, while averages of the derived AT were fluctuated from 3 [Formula: see text] 2 to [Formula: see text] for five compartments. The proposed refined equation estimated the internal dose from gamma-ray as [Formula: see text][Formula: see text]mSv for eight patients according to a fast screening method, which defined human body as a spherical ball to simplify the calculation in reality. The proposed MATLAB-based fitting of in-vivo data with the theoretical results was instrumental for assessing the radiation dose received by the Tc-99m MIBI scan participants.

We conducted a clinical trial to analyze human serum containing carbamazepine by using the differential pulse voltammetry (DPV) method with a glassy carbon electrode, and compared it with the fluorescence polarization immunoassay (FPIA). Thirty patients, who visited our hospital to have their serum carbamazepine level checked, were enrolled. Ten mL of venous blood was collected from each patient and analyzed by DPV and FPIA methods. The correlation between the carbamazepine concentrations determined by DPV and FPIA was good, with an RSQ of 0.998. The similarity of the results indicates that these two methods can be used interchangeably. The DPV method using a glassy carbon electrode may be a potential alternative method to determine the carbamazepine level in human serum.

This study examines the relationships between the herding of various investor groups andtrading noise in the Taiwan stock market to determine whether any of the investor groupstend to herd rationally. The study uses a unique and comprehensive data set on intradaytransactions and limit order books of the Taiwan Stock Exchange (TWSE). We calculate thehigh-frequency herding measures and trading noise in a call auction market. We find thatinstitutional investors are likely to be informed traders and herd rationally based on superiorinformation. Institutional investors’ herding has a negative impact on trading noise. Theirbuy (sell) herding predicts positive (negative) future market returns. By contrast, the herdingof individual investors tends to contain limited information, as it increases trading noise; thebuy (sell) herding of individuals is negatively correlated with future market returns. Thesefindings are more significant for stocks with higher turnover.Keywords Trading noise; Herding; Institutional investors; Individual investors; Intradaytransactions.JEL Classification: G1, G12, G14, G15, L11*Acknowledgements: The authors thank the editors and the two anonymous referees for theirconstructive comments. The authors also acknowledge the financial support from NationalScience Council of Taiwan (Grant no. NSC 99-2410-H-032-030-), as well as the Taiwan StockExchange for data support.**Corresponding author: Shih-Chuan Tsai, 11F-2, No.18, Jin-Shan South Road, Section 2,Taipei, Taiwan. Tel: +886-277343299, Fax: +886-2-23222668. email: chuant@ntnu.edu.tw.

In this study, we employ a statistical arbitrage approach to demonstrate that momentum investment strategy tend to work better in periods longer than six months, a result different from findings in past literature. Compared with standard parametric tests, the statistical arbitrage method produces more clearly that momentum strategies work only in longer formation and holding periods. Also they yield positive significant returns in an up market, but negative yet insignificant returns in a down market. Disposition and over-confidence effects are important factors contributing to the phenomenon. The over-confidence effect seems to dominate the disposition effect, especially in an up market. Moreover, the over-confidence investment behavior of institutional investors is the main cause for significant momentum returns observed in an up market. In a down market, the institutional investors tend to adopt a contrarian strategy while the individuals are still maintaining momentum behavior within shorter periods. The behavior difference between investor groups explains in part why momentum strategies work differently between up and down market states. Robustness tests confirm that the momentum returns do not come from firm size, overlapping execution periods, market states definition or market frictions.

The purpose of the present study was to conduct a systematic review and meta-analysis of the published literature to assess the diagnostic performance of FDG-PET or PET/CT in the detection of recurrent colorectal cancer (CRC) rising in patients with elevated CEA. The authors conducted a systematic MEDLINE search of published articles. Two reviewers independently assessed the methodological quality of each study. We estimated pooled sensitivity and specificity and positive and negative likelihood ratios, and summary receiver-operating characteristic curves in the detection of recurrent CRC in patients with elevated CEA. Eleven studies with a total of 510 patients met the inclusion criteria. One hundred and six patients (106/510 = 20.8 %) had true-negative FDG-PET (PET/CT) results in detection of recurrent CRC when rising CEA. The pooled estimates of sensitivity and specificity and positive and negative likelihood ratios of FDG-PET in the detection of tumor recurrence in CRC patients with elevated CEA were 90.3 % (95 % CI, 85.5–94.0 %), 80.0 % (95 % CI, 67.0–89.6 %), 2.88 (95 % CI, 1.37–6.07), and 0.12 (95 % CI, 0.07–0.20), respectively. The pooled estimates of sensitivity and specificity and positive and negative likelihood ratios of FDG-PET/CT in the detection of tumor recurrence in CRC patients with elevated CEA were 94.1 % (95 % CI, 89.4–97.1 %), 77.2 % (95 % CI, 66.4–85.9 %), 4.70 (95 % CI, 0.82–12.13), and 0.06 (95 % CI, 0.03–0.13), respectively. Whole-body FDG-PET and PET/CT are valuable imaging tools for the assessment of patients with suspected CRC tumor recurrence based on the increase of CEA.

We set out in this study to examine advantaged investors' order choices by computing gains and losses from executed orders in a pure order-driven stock market, the Taiwan Stock Exchange. We carry out an event study on the profitability of order categories around annual earnings announcements. We use a unique and extremely comprehensive dataset which can accurately classify executed orders by order size and aggressiveness for each investor group. We find that, as a group, individual investors are less informed about imminent corporate earnings announcements and the related value implications. Domestic institutions with better local connections have access to privileged information, resulting in significant trading profits in the pre-event window. Informed domestic institutions tend to employ large-sized orders to take up all of the available liquidity. Although limited in terms of private information, foreign institutions with superior expertise accrue profits by trading conservatively through the use of small- to medium-sized orders and less aggressive prices. Order flows are more serially correlated in the pre-event period, especially medium-sized orders from foreign institutions. The results are robust after controlling for various market condition variables. They also hold to different lengths of pre-event window and in the absence of price impacts.

The use of prednisolone is one major risk factor for osteonecrosis in patients with systemic lupus erythematosus. Bone scintigraphy can be a diagnostic tool for early diagnosis. We present a case who had collar osteophytes at the bilateral femoral heads, which mimicked osteonecrosis in the planar bone scintigram. An SPECT/CT scan avoided this pitfall and increased the diagnostic accuracy for osteonecrosis.

A 53-year-old female patient suffered from pain in almost her entire body, particularly the joints. Chest computed tomography revealed multiple lymphadenopathies over cervical, mediastinal, and axillary areas. A fluorine-18-deoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed increased FDG uptake in many lymph nodes and the spleen. Lymphoma was suspected. However, the result of a biopsy showed no malignancy, and the gallium-67 citrate scan showed no gallium-avid tumor throughout the whole body. Adult-onset Still's disease was diagnosed and the patient responded well to steroid therapy. The follow-up PET/CT six months later showed complete remission of the FDG-avid lesions seen in the previous PET/CT. Our study suggests that FDG PET/CT combined with gallium-67 scan may be helpful in diagnosing patients with adult-onset Still's disease. In addition, the use of FDG PET/CT alone may be useful for the evaluation of disease distribution, disease activity, and therapeutic response.

This paper examines the role of institutional investors in improving firm performance through the channel of corporate investment decisions. We find that the interaction effect between institutional ownership and capital expenditures is significantly related to firm performance. We examine this relationship for different types of institutional investors, and find that investment advisors are most effective monitors in improving firm performance through corporate investment. Moreover, we find that the monitoring role of institutional investors becomes more important when internal governance is weak. Institutional ownership and other forms of corporate governance mechanisms (including CEO incentive compensation and control, shareholder right provisions, and board of director monitoring) operate as substitutes, rather than complements, in improving capital expenditure decisions. Copyright © 2012 ASAC. Published by John Wiley & Sons, Ltd. Resume Cet article examine le role que les investisseurs institutionnels jouent dans l'amelioration de la performance des entreprises a travers les decisions de placement des societes. Il montre que l'effet d'interaction entre la propriete institutionnelle et les depenses en capital est fortement lie a la performance d'entreprise. L'examen de cette relation pour differents types d'investisseurs institutionnels revele que les conseillers en investissement sont les mieux places pour veiller a l'amelioration de la performance d'entreprise a travers les placements de la societe. Il ressort des resultats que le role de surveillance attribue aux investisseurs institutionnels gagne en importance lorsque la gouvernance interne devient faible. La propriete institutionnelle et les autres formes de mecanismes de gouvernance d'entreprise (y compris le controle des PDG et les compensations qui leur sont accordees, les dispositions relatives au droit des actionnaires, le suivi du conseil d'administration) fonctionnent non pas comme de supplements, mais plutot comme des substituts dans l'amelioration des decisions de depense en capital.Copyright © 2012 ASAC. Published by John Wiley & Sons, Ltd.

This study shows that trading causes friction in the market. However, when the market opens, trading of individuals removes market friction, while that of institutional trading does not. The situation during the rest of the day is just the opposite. The uneven behavior of trading noise across investors and time of day makes it a specific, rather than general, transaction cost, contrary to Stoll's (2000) finding. Intraday trading activity sup- presses both order width and depth, as proxies for trading intensity, and therefore creates noise or friction in the market. Our findings support the proposed financial transaction tax in the European Union. Trading in markets involves general transaction costs applicable to the entire market, as well as specific costs borne only by certain investors. The former causes friction in trading, which could be noise, as argued in Stoll (2000), or herding out of information cascades (see, among others, Avery and Zemsky 1998; Banerjee 1992; Bikhchandani et al. 1992; Nofsinger and Sias 1999). The latter could also take the form of information asymmetry, as discussed by Admati (1991), Diamond and Verrecchia (1981), Easley and O'Hara (1992), Easley et al. (1997), Glosten and Milgrom (1985), and Kyle (1985). This study addresses the role of trading noise as friction affecting market participants, especially in the presence of trading concentration. Our interest is in whether trading activity itself adds to or drives down this friction, and how the relationship is affected by investor type, market capitalization of stocks, and time of day the trading takes place. If trading brings friction, then our findings provide support for a financial transaction tax, which is encountering much resistance. We attempt to verify in this study whether trading noise really qualifies as a general transaction cost, that is, as market-wide friction, in an intraday framework. It has been well documented (Amihud and Mendelson 1987; Stoll 2000; Stoll and Whaley 1990) that stock return volatility is the highest right after the market opens. Stoll (2000) sug- gests that the high volatility is caused by friction, a general transaction cost for everyone in the market. Alternatively, Lakonishok et al. (1992) and Wermers (1999) stress that volatility is closely related to information-induced herding behavior. However, Lin et al. (2012) argue that a comparative advantage in search cost dictates a polarization of trading activity across investors, firm size, and time of day. Hu (2006) applies a return decomposition mechanism to conclude that specific transaction costs cause the market to be the most volatile at opening, since frictional noises are the smallest during the day. We adopt this concept but attempt to identify its driving factors.

This paper examines the effect of incorporating liquidity into the Nelson-Siegel-Svensson model from the perspective of out-of-sample forecasting ability and trading performance. The liquidity consideration reduces the distortion from concentrated trading activities and significantly increases the forecasting ability of the dynamic curve-fitting model. Taking liquidity into account can improve the risk-adjusted returns of a trading strategy developed from the forecasting error series. The improvement in the forecasting ability and the trading performance is consistent across different sets of parameter values and different bond issues, and it becomes more substantial when the forecasting period expands.

In this study, we analyze investor trading behavior based not on information-related assumptions but on the search model of Vayanos and Wang (2007). Our study shows that search cost dictates trading polarization across investors, firm size, and time of day. We find that individual investors prefer to trade at market open, while institutional investors trade more heavily near market close. Trading costs indicate that it is less costly for institutional investors to trade large cap stocks at market close than at open. Search cost is related significantly to order-based market liquidity measures depending on time of day, market capitalizations, and investor type.

Hemorrhoids are very common in adults. The data regarding the incidence of high 2-fluoro-2-deoxy-D: -glucose (FDG) uptake in hemorrhoids is incomplete. In this study, we evaluated FDG uptake in hemorrhoids and calculated the rate of high FDG uptake in these lesions.One hundred and seventy six subjects who undertook whole body FDG-PET for health screening examination were investigated retrospectively. All patients had colonoscopy and 156 subjects were found to have hemorrhoids and 20 had no hemorrhoids. Quantitative analysis of FDG uptake in the anal region was performed by calculating the maximum standard uptake value (SUV(max)).The SUV(max) ranged from 1.8 to 4.1 (2.8 ± 0.6) for normal subjects and ranged from 1.4 to 8.3 (2.9 ± 0.8) for patients with hemorrhoids. No statistical difference was noted between these two groups using a Student's t-tests. If the highest SUV(max), which was 4.1 in normal subjects, was used as a cutoff, 5.1% (8/156) hemorrhoid patients had a SUV(max) greater than 4.1.Hemorrhoids can be one possible cause of focal high FDG uptake in the rectum.

This article examines the impact of the 2007–2009 Global Financial Crisis on the interrelationships among global stock markets and the informational role of the TED spread as perceived credit risk. The current crisis originated from the dominant US market has a prompt and pervasive spillover effect into other global markets. Using the Vector Autoregressive (VAR) model, Granger causality test, cointegrating Vector Error Correction Model (VECM), we document enhanced leadership of the US market with respect to UK, Hong Kong, Japan, Australia, Russia and China markets during the crisis. Consistent with the contagion theory, the interdependence among international stock markets becomes stronger in the crisis. The TED spread serves as a leading ‘fear’ indicator and adjusts to new information rapidly during the crisis. While the impact of orthogonalized shocks from the US market on other global markets increases by at least two times during the crisis, the impact of orthogonalized shocks from the TED spread on g...

PurposeThe purpose of this paper is to examine the ways in which stock market valuation and managerial incentives jointly affect merger and acquisition (M&A) decisions and post‐M&A performance, and to provide new evidence on the agency implications where such acquisitions are driven by the stock market.Design/methodology/approachUtilizing all publicly‐traded US firms in the NYSE, AMEX and NASDAQ during the period from 1992 to 2005 (excluding financial and utility firms), obtained from COMPUSTAT, CRSP, I/B/E/S, and the M&A database provided by SDC Platinum, this paper adopts a two‐stage approach: the first stage, predicts the probability of an M&A based on the market valuation variables; the second stage, regresses the post‐M&A firm performance on the predicted probability of a merger or acquisition from the first stage and other control variables.FindingsMarket valuation has a significant influence on corporate acquisition decisions, particularly for those firms whose compensation packages include less managerial equity ownership, more executive stock options and no long‐term incentive plans, and in those firms where CEOs are serving on the board of directors. The value‐destroying acquisitions made by these types of managers are likely to be financed using the firms' stocks, executed with high premiums and undertaken during periods of high market valuation.Originality/valueThe main finding suggests that market‐driven acquisitions could be value destroying when managers engage in opportunistic acquisitions for reasons of self‐interest. Managerial myopia, overconfidence, misaligned incentives, empire‐building motives and poor corporate governance can all exacerbate the agency problem of market‐driven acquisitions.

This paper provides new evidence on the relations between managerial and institutional ownerships and firm performance. These relations are found to be affected by firm’s stock price informativeness and corporate governance. Based on a sample of US firms from NYSE, AMEX, and NASDAQ between 1989 and 2006, we document three important findings. First, managerial ownership and firm future performance are non-linearly related; the positive relation is stronger for firms with less informative prices or more agency problems. This finding suggests that poor governance and uninformative price increase the importance of managerial value creation for their firms by improving internal governance. Second, institutional ownership has a significant positive impact on firm future performance, with larger impact for firms with less informative prices or good governance. However, institutional ownership, which reflects external monitoring, has a weaker positive effect compared to managerial ownership, which controls for internal governance. Third, the interaction between managerial ownership and institutional ownership has a significant positive impact on firm future performance, suggesting that there are synergistic effects of internal and external corporate governance mechanisms in improving firm value.

This paper develops a dynamic model of the financing and operating decisions of firms in the presence of information asymmetry. When the value of growth opportunities is not fully recognized, securities are undervalued, thus influencing the financing and investment decisions. The agency-based underinvestment problem is re-examined under information asymmetry. For firms with greater growth opportunities, the investment distortion resulting from information asymmetry is especially significant. Information asymmetry also increases the expected bankruptcy cost. The cost of information asymmetry in terms of both the firm value and the information spread under the optimal capital structure could be substantial.

PURPOSE Renal biopsy is crucial for management of lupus nephritis. However, it is invasive and can cause bleeding and infection. In our previous study, we developed a semiquantitative method for gallium renal imaging and demonstrated a good correlation between the left kidney-to-spine ratio (K/S ratio) and the results of renal biopsy. However, the accuracy of left K/S ratio is compromised by the variation of spinal gallium uptake, especially in patients with extraordinarily high or low gallium uptakes in the spine. In this study, we developed an absolute quantitative method and compared the results of quantitative gallium images, semiquantitative gallium images, visual methods, and renal biopsies. METHODS Thirty-four patients with lupus nephritis were enrolled and underwent renal biopsy to determine activity index (AI) and chronicity index. A delayed 48-hour gallium scan was also performed and interpreted by visual, semiquantitative, and absolute quantitative methods. For absolute quantitative analysis, a standard solution with activities of approximately 555 KBq (15 μCi) was prepared and poured into a 5-mL tube, which was placed close to the patient. ROIs were drawn around the outer edge of the left kidney as well as around the outer edges of the standard. A kidney uptake index (KUI) was calculated, and the results were compared with K/S ratio, visual grading, and renal biopsies. RESULTS Kidney uptake index had the best correlation with AI among the 3 methods using Spearman rank correlation test. The Spearman R values were 0.78, 0.71, and 0.61 for KUI, K/S ratio and visual grading, respectively. Chronicity index did not correlate well with the results of any of the 3 methods. In addition, AI was significantly higher in patients with a KUI equal to or greater than 1.5, when compared with patients with a KUI lower than 1.5 (P = 0.00001 by Mann-Whitney U test). Using a K/S ratio of 0.95 as a cutoff value, AI also showed a statistically significant difference with P = 0.0001. When a visual grading of 2 was used as a cutoff value, P = 0.0008. The difference in AI was most significant when the statistical value was based on the KUI. CONCLUSIONS The KUI showed better correlation with the results of renal biopsy than the K/S ratio and the visual grading. We suggest that the KUI from the absolute quantitative renal gallium scintigraphy may be a useful parameter for evaluating the disease activity in lupus nephritis.

Indium-111 and 99mTc have been proposed for colonic transit study, but 111In is expensive and the half-life of 99mTc is too short for the study. Gallium-67 citrate is inexpensive and has a suitable half-life. In our previous study, we successfully labeled 67Ga-citrate activated charcoal, and the labeling efficiency exceeded 91% after a 96 hour incubation period. In this work, we evaluated the influence of the size of activated charcoal particles on the labeling efficiency with 67Ga-citrate. The data showed that the influence of particle size on the labeling efficiency of activated charcoal with 67Ga was insignificant. Both sizes of activated charcoal particles can be used for labeling with 67Ga in colonic transit study.

Firms alter investing decisions when there is debt in the capital structure. Security design features can exacerbate the situation. This article studies how strategic debt service may affect investment distortions resulting from debt financing in a dynamic framework. When the production decision involves an expansion option, the shareholders’ option to strategically default on the outstanding debt eliminates bankruptcy costs but, in contrast to previous literature where production decisions are fixed, leads to suboptimal investing decisions. This is due to higher wealth transfers from shareholders to debt holders upon exercise of the growth option. Strategic debt service, therefore, may reduce the value of the firm. The setting of an endogenous production set offers a potential explanation for empirical observations of wide credit spreads and low leverage.