News Sentiment and the Investor Fear Gauge

This note examines the relationship between aggregate news sentiment and changes in the implied volatility index (VIX). A significant negative contemporaneous relationship between changes in VIX and news sentiment is discovered. The relationship is asymmetric whereby changes in VIX are larger following the release of negative news items

(WP 2011-01) It Takes Two: The Incidence and Effectiveness of co-CEOs

This study examines the phenomenon of co-CEOs within publicly traded firms. Although shared executive leadership is not widespread, it occurs within some very prominent firms. We find that co-CEOs generally complement each other in terms of educational background or executive responsibilities. Our results show that firms most likely to appoint co-CEOs have lower leverage, a more limited firm focus, less independent board structure, fewer advising directors, lower institutional ownership and greater levels of merger activity. The governance structure of co-CEO firms suggest that co-CEOships can serve as an alternative governance mechanism, with co-CEO mutual monitoring substituting for board or external monitoring and co-CEO complementary skills substituting for board advising. An event study indicates that the market reacts positively to appointments of co-CEOs while a propensity score analysis shows that the presence of co-CEOs increases firm valuation

Non-Diversifiable Volatility Risk and Risk Premiums at Earnings Announcements

This study seeks to determine whether earnings announcements pose non-diversifiable volatility risk that commands a risk premium. We find that investors anticipate some earnings announcements to convey news that increases market return volatility and pay a premium to hedge this non-diversifiable risk. In particular, we find evidence of risk premiums embedded in prices of firms' traded options that are significantly positively associated with the extent to which the firms' earnings announcements pose non-diversifiable volatility risk. In addition, we find that volatility risk premiums are concentrated among bellwether firms and result in predictable variation in option straddle returns around earnings announcements. Taken together, our findings show that some earnings announcements pose non-diversifiable volatility risk that commands a risk premium

COVID-19 and venous thromboembolism: A narrative review

COVID-19 (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) is associated with coagulopathy through numerous mechanisms. The reported incidence of venous thromboembolism (VTE) in hospitalized patients with COVID-19 has varied widely, and several meta-analyses have been performed to assess the overall prevalence of VTE. The novelty of this coronavirus strain along with its unique mechanisms for microvascular and macrovascular thrombosis has led to uncertainty as to how to diagnose, prevent, and treat thrombosis in patients affected by this virus. This review discusses the epidemiology and pathophysiology of thrombosis in the setting of SARS-CoV-2 infection along with an updated review on the preventative and treatment strategies for VTE associated with SARS-CoV-2 infection

Isolated Hepatic Tuberculosis: an uncommon presentation of a common entity.

Hepatic tuberculosis is commonly encountered in patients with widespread miliary disease. Isolated affection of the liver is extremely rare. We present a case of a young woman who presented with a subacute afebrile hepatic failure. Investigations including a liver biopsy proved that the presentation was due to granulomatous hepatitis secondary to mycobacterial infection of the liver. It is important that tuberculosis be kept in mind especially in endemic areas even in atypical clinical scenarios by clinicians, radiologists, and pathologists. Use of anti-tuberculous drugs in such cases is usually successful and must be instituted early

Proline accumulation and nitrate reductase activity in contrasting sorghum lines during mid-season drought stress

Six lines of sorghum (Sorghum bicolor L. Moench) with differing drought resistance (IS 22380, ICSV 213, IS 13441 and SPH 263, resistant and IS 12739 and IS 12744, susceptible) were grown under field conditions in the semi-arid tropics and analysed for proline and nitrate reductase activity (NRA; EC 1.6.6.1) during a mid-season drought. The resistant lines accumulated high levels of proline, while the susceptible lines showed no significant proline accumulation. Most of the proline was accumulated after growth of the plants had ceased. In a separate greenhouse experiment, most of the proline was found in the green rather than the fired portions of leaves. The levels returned to that of irrigated controls within 5 days of rewatering. Proline levels increased as leaf water potential and relative water content fell, and there was no apparent difference among the different sorghum lines with change in plant water status. Susceptible lines accumulated less proline than resistant lines as leaf death occurred at higher water potentials. Proline accumulation may, however, contribute to the immediate recovery of plants from drought. Leaf NRA reached high levels at about 35 days after sowing in both the stressed and irrigated plants, after which it declined. The decline in NRA was more pronounced in the stressed than in the irrigated plants and closely followed changes in the growth rate. Upon rewatering, NRA increased several-fold in all the lines and, in contrast to proline accumulation, genotypic differences in NRA were small, both during stress and upon rewatering. The high sensitivity of NRA to mild drought stress was reflected in the rapid decline of activity with small changes in leaf water potential and relative water content. The results are discussed in the light of a possible role for proline during recovery from drought, and the maintenance of NRA during stress and its recovery upon rewaterin

Cortical Venous Thrombosis

Background Our study retrospectively reviewed the presentation, neuro-radiological findings, and outcomes of eight adult patients presenting at our institution with subarachnoid haemorrhage (SAH), which was subsequently proven to be due to cortical venous thrombosis (CVT). Methods We reviewed the case records and neuroimaging findings of eight patients diagnosed with SAH and CVT over a span of two years at our institution, a tertiary care centre in Western India. All details pertaining to their presentation, clinical findings, neuroimaging, management, and outcome following therapy with anticoagulants were collected until patient discharge. Results There were a total of eight patients, with the average age being 34 years (range 25–42). Only one patient was female. Six patients had a history of recent binge drinking. None of the patients had a past or family history of common risk factors for thrombosis. All patients presented acutely, with headache (n=6) and seizures (n=6) being the most common presenting features, occurring in three-quarters of the patients examined. Non-contrast computed tomography (NCCT) was the initial imaging study for all but one of the patients and showed cortical SAH (cSAH) without basilar haemorrhage. Magnetic resonance imaging/magnetic resonance venography (MRI/MRV) confirmed the underlying CVT. Unfractionated heparin was used in all cases. Seven patients improved and were discharged on oral anticoagulation. The eighth patient died. Conclusion Localised cSAH with sparing of basal cisterns can be a presentation for CVT. In patients with cSAH, MRI/MRV can be useful to make a diagnosis of CVT. Anticoagulation for CVT, even in the presence of SAH was related to seven out of eight patients being discharged

The Arabidopsis

The integration of cell division in root growth and development requires mediation of developmental and physiological signals through regulation of cyclin-dependent kinase activity. Cells within the pericycle form de novo lateral root meristems, and D-type cyclins (CYCD), as regulators of the G(1)-to-S phase cell cycle transition, are anticipated to play a role. Here, we show that the D-type cyclin protein CYCD2;1 is nuclear in Arabidopsis thaliana root cells, with the highest concentration in apical and lateral meristems. Loss of CYCD2;1 has a marginal effect on unstimulated lateral root density, but CYCD2;1 is rate-limiting for the response to low levels of exogenous auxin. However, while CYCD2;1 expression requires sucrose, it does not respond to auxin. The protein Inhibitor-Interactor of CDK/Kip Related Protein2 (ICK2/KRP2), which interacts with CYCD2;1, inhibits lateral root formation, and ick2/krp2 mutants show increased lateral root density. ICK2/KRP2 can modulate the nuclear levels of CYCD2;1, and since auxin reduces ICK2/KRP2 protein levels, it affects both activity and cellular distribution of CYCD2;1. Hence, as ICK2/KRP2 levels decrease, the increase in lateral root density depends on CYCD2;1, irrespective of ICK2/CYCD2;1 nuclear localization. We propose that ICK2/KRP2 restrains root ramification by maintaining CYCD2;1 inactive and that this modulates pericycle responses to auxin fluctuations

Outcomes of patients with hematologic malignancies and COVID-19: A systematic review and meta-analysis of 3377 patients

Outcomes for patients with hematologic malignancy infected with COVID-19 have not been aggregated. The objective of this study was to perform a systematic review and meta-analysis to estimate the risk of death and other important outcomes for these patients. We searched Pubmed and EMBASE up to August 20, 2020, to identify reports of patients with hematologic malignancy and COVID-19. The primary outcome was a pooled mortality estimate, considering all patients and only hospitalized patients. Secondary outcomes included risk of ICU admission and ventilation in hospitalized patients. Subgroup analyses included mortality stratified by age, treatment status, and malignancy subtype. Pooled prevalence, risk ratios (RR), and 95% confidence intervals (CI) were calculated using a random-effects model. 34 adult and 5 pediatric studies (3377 patients) from Asia, Europe, and North America were included (14/34 adult studies included only hospitalized patients). The risk of death amongst adult patients was 34% (95% CI 28-39, N=3240) in this sample of predominantly hospitalized patients. Patients aged >60 years had a significantly higher risk of death than patients 60 years have significantly higher mortality, and pediatric patients appear to be relatively spared. Recent cancer treatment does not appear to significantly increase the risk of death

Impact of mild thrombocytopenia on bleeding and recurrent thrombosis in cancer

Thrombocytopenia occurs frequently in patients with cancer-associated thrombosis (CAT), however prospective evaluation of clinical outcomes following randomization to anticoagulants is limited. The HOKUSAI VTE Cancer study was a randomized, open-label, non-inferiority, phase III trial comparing dalteparin with edoxaban in CAT patients. This post hoc analysis of Hokusai VTE Cancer Study was performed to compare outcomes in patients with platelet count ≤100x109/L at one or more specified time points (baseline, 1-month, or 3-month) versus those without thrombocytopenia. Cumulative incidences at 180 days were calculated with death as a competing risk. The primary outcome was major bleeding; secondary outcomes were clinically relevant non-major bleeding (CRNMB), recurrent thrombosis, and survival. The analysis included 1,045 patients with primarily solid tumor malignancies (89%), median age 65 years, and 52% male. The thrombocytopenia group comprised 9.6% (N=101) of the cohort and relative to the non-thrombocytopenia cohort (N=944), experienced significantly higher major bleeding (9.0% vs. 4.0%, sub-distribution hazard ratio [SHR] =2.4; P=0.02) and CRNMB (17.9% vs. 9.6%, SHR=2.0; P=0.01). Thrombocytopenia did not impact recurrent venous thromboembolic event (VTE) (9.8% vs. 7.4%, SHR=1.3; P=0.37) nor overall mortality (21.8% vs. 26.0%, HR=0.9; P=0.48). Major bleeding was higher in patients with thrombocytopenia and gastrointestinal malignancies receiving edoxaban versus dalteparin (16.8% vs. 0; P<0.01) but similar for patients with other malignancies (P=0.30). In patients with hematologic malignances and thrombocytopenia major bleeding was higher for patients receiving dalteparin compared to edoxaban (19.0% vs. 0; P<0.01). Mild thrombocytopenia was associated with a doubling in risk of major hemorrhage in patients receiving anticoagulation for CAT. Bleeding risk for edoxaban and dalteparin varied in gastrointestinal and hematologic malignances in patients with thrombocytopenia (clinicaltrails gov. Identifier: NCT02073682)