Search

The interfacial compatibility between the graphite/carbon black composite counter electrode (Gr/CB CE) and the perovskite layer is a crucial determinant of the performance of the hole-transport-layer-free carbon-based perovskite solar cells, and judicious selection of the Gr/CB CE application method is essential for achieving an optimum contact. In this work, three different types of Gr/CB CEs application methods are investigated: (1) deposition of Gr/CB on the fluorine-doped tin oxide (FTO) substrate, followed by clamping to the perovskite layer, (2) direct deposition of Gr/CB onto the perovskite layer, and (3) deposition of Gr/CB onto the PbI

Heart failure represents a major global cause of morbidity and mortality. Ivabradine is a selective funny current (If) inhibitor, which acts on the sinoatrial node, resulting in a reduction in heart rate. Ivabradine is currently licensed for use in patients with symptomatic heart failure with reduced ejection fraction and a heart rate persistently at least 70 beats per minute in spite of otherwise optimal prognostic heart failure pharmacotherapy. In this review article, we examine the mechanism of action of ivabradine, evaluate the clinical trials underpinning its application in heart failure and discuss its current recommended clinical use in this capacity.

Background Navigated total hip arthroplasty (THA) can employ intra-osseous pins through a separate incision to secure reference arrays to the iliac crest. This study is the first to investigate the consequences of pin use in THA in vivo. Methods A prospective, consecutive series of 43 patients presenting for navigated THA were included. Two temporary 125 × 4 mm Schanz screws were inserted into the iliac crest for the attachment of a reference array. Telephone follow-up occurred at 6 and 12 weeks post-operatively. Patients were asked about pain, interference with daily activities, how often the wound was noticed, and duration of discomfort. Patient body mass index was recorded. Results The follow-up rate was 100%. Pin site pain at any time post-operatively was reported by 24 patients (56%). This improved to 30%, 9%, and 2% at 3, 6, and 12 weeks, respectively. On average, pain lasted for 16 days total. The most common complaints after pain were clothing discomfort (23%), pain when wearing a belt (12%), or pain when mobilizing (9%). For the majority (98%) of patients, all symptoms had resolved by 12 weeks. There was no nerve injury, pin site fracture, infection, or screw breakage. Patients with body mass index greater than 30 kg/m2 were up to 3 times more likely to experience pin site pain (P = .05), and had a longer duration of pain (P = .04). Conclusion Surgeons and patients should be aware that using navigational pins for array fixation carries low complication rates but often will cause pain and irritation that resolves in the short term.

Machine learning models used for energy conversion system optimization cannot extrapolate outside the bounds of training data and often produce physically unrealistic results when making predictions in regions of sparse training data. The toy model concept introduced in this work allows machine learning models to extrapolate to some extent and also reduces the possibility of physically unrealistic results. It uses physics to shrink the model input (feature space) of data-based models, so that extrapolations in the data-based feature space tend to become interpolations in the physics-based (toy variable) feature space. The physics-based model can be any model or experiment that can shrink the feature space without affecting interpolation and is termed a ‘toy model’ because it does not need to be accurate or make predictions of interest. The concept has been applied to model experimental data obtained from three complex systems: a. Aerodynamic forces on a spinning and vibrating baseball with inclined axis of rotation (toy model: CFD model), b. Hydraulic turbine efficiency (toy model: PIV images of flow through stationary blades), and c. Combustion generated engine emissions (toy model: system-level 1-D model). All extrapolations were converted into interpolations for the first two systems while a 75% conversion was achieved for the emission predictions. The engine toy model produced 736,281 possible feature spaces from which one unique feature space was chosen for every prediction based on agreement between different machine learning algorithms. It is shown that the ability of the toy variables to reorganize the data is important, while their accuracy is relatively unimportant. The toy model concept was demonstrated to work with neural networks and regression, and can be used to increase model robustness or reduce training data requirements.

Nanostructured WO3 electrodes coated with BiVO4 are known to be among the best performing BiVO4-based photoanodes for photoelectrochemical water splitting. However, record performance is only achieved using intricate and costly electrode fabrication processes; when lower-cost, more scalable methods are used, performance drops significantly. Here, we show that a low-cost successive ionic layer adsorption and reaction method, which has received relatively little attention for the preparation of BiVO4, can be used to convert nanoporous WO3 films prepared by spin coating into high-performance WO3/BiVO4 photoanodes. After treatment with a cobalt phosphate co-catalyst, optimized WO3/BiVO4 photoanodes can reach water oxidation photocurrent densities of up to ~3.4 mA cm-2, with a photocurrent onset potential of ~0.56 V vs. RHE. Furthermore, an investigation by impedance spectroscopy showed that the electron diffusion length in both types of film is longer than the film thickness, which is an important requirement for an efficient nanostructured electrode. These results highlight the role that simple deposition methods such as SILAR can play in the preparation of nanocomposite photoanodes for PEC applications.

Current National Market System rules do not recognize odd lots in the protected intermarket quote. Thus, liquidity demanders can receive worse prices than they would receive if odd lots were protected. The effect of ignoring odd lots is magnified because off-exchange trades (over one-third of total volume) benchmark executions against the protected quote. The authors identify time intervals with an unprotected odd lot limit order at a price better than the protected quote and examine trades during those intervals for 10 high-priced stocks during one week in 2015. They find over 406,000 intervals, representing 37% of sample stock trading time, in which an odd lot order betters the protected quote. Examining trades within these intervals, they find nearly 55,000 cases in which the trade price is worse than the odd lot price. In total, the price disimprovement in their 10 stocks is $554,675 for the week examined. This previously undocumented trading cost is associated with the corporate decision not to split a stock’s price in a market in which odd lot orders are excluded from the protected quote.

Fees charged by U.S. equity exchanges for services such as non-core market data, connectivity, and co-location have become controversial. Recently, the Securities and Exchange Commission required the exchanges justify hundreds of past fee increases. In their defense, exchanges argue that the fees that they charge are constrained by competition for order flow between the three major exchange families. To the authors’ knowledge, no extant work associates fee changes with exchange revenues. We gather fee increases and exchange financial statement information between 2006 and 2016 to examine the relation between fees and revenues. We find that, when statistically significant, revenue increases with fee increases without a consistently strong volume effect, which suggests that any decrease in subscriptions due to fee increases is more than offset by the revenue increase from the remaining subscribers.

Most financial security trading venues prioritize competing liquidity providers with price-time priority; entities displaying the best-priced limit order earliest trade with the next opposite-sided liquidity-demanding order. The New York Stock Exchange (NYSE) rule putting traders “on parity” is a vestige of the traditional floor-based trading model and favors floor-based traders. Parity requires that orders from floor brokers, the designated market maker, and the top of the electronic limit order book trade together. That is, floor trading interests can trade ahead of equally priced, previously arriving orders in the limit order book. The NYSE posits that floor traders provide valuable services to the investing public and one approach to remunerating them for these services is deviating from strict time priority. The cost of the potential benefits of the NYSE’s business model is not transparent. Our research is an initial attempt to quantify this cost.

Introduction Accurate prosthetic cup placement is important in total hip arthroplasty (THA) and can be influenced by patient positioning. This study aims to assess the accuracy of patient positioning prior to THA, describe a new technique of assessment, and evaluate the influence of body mass index (BMI) on positioning error. Methods A consecutive series of 37 patients undergoing unilateral THA were investigated. After patient positioning in lateral decubitus, a lateral fluoroscopic image through the table was taken. The C-arm of the image intensifier was manipulated in 2 planes (coronal, transverse) until a perfect lateral view of the pelvis was obtained, defined as when the native acetabulae were superimposed. Degrees of positioning error in the 2 planes were recorded, along with patient BMI. Results There were 6 patients (16%) positioned within 2° of true lateral in both planes. A further 21 patients (57%) had an error of 5° or more in at least 1 plane. Mean absolute positioning error was 3.0° (SD 2.2°; range 0°-9°) and 3.0° (SD 3.2°; range 0°-13°) in the transverse and coronal planes respectively. Pelvic adduction in the coronal plane was 4.5 fold more likely than abduction (49% vs. 11%). Correlation was shown between patient BMI and the combined error in the 2 planes (R = 0.48, p = 0.001). Discussion Fluoroscopic positioning assessment prior to THA demonstrates that significant malpositioning is common and more likely with increasing BMI. This technique may be particularly useful for patients with a BMI of >30 kg m-2.

In Canada, most jurisdictions have experienced stagnation or even increases in traffic injuries lately, leading to reconsider prevention strategies. The Swedish approach ‘Vision Zero’, as stated in its name, aims to reduce the number of fatal and serious road collisions to zero. First introduced 20 years ago, it represent a turning point in the way we view road safety around the world. In the last years, major Canadian cities and provinces adopted this approach. However, it is not clear how they will adapt it to the North American context, nor how stakeholders collaborate together within the Vision Zero framework to ensure the reduction in traffic injuries. This project explore the multi-sectoral content of Canadian Vision Zero initiatives using three sources: official documents from jurisdictions involved in VZ; content of a workshop held in 2017 on VZ implementation (discussions on: actors, data, indicators and methods needed, 50 participants); and interviews with key stakeholders in five cities (Vancouver, Calgary, Edmonton, Toronto, Montreal). Preliminary results show that there is no consistent method to implement VZ plans or measure their impacts on road safety: while some jurisdictions have more formal action plans, targets and dedicated resources, other have included the VZ approach within their transportation plans. Despite the fact that participants suggested a wide range of actors (from provincial health authorities to cycling advisory groups and auto manufacturer) who should be involved, very few of the actual initiatives includes a broad range of actors outside the municipal level. Our research also confirms the need for more ccoordination between actors: the alignment of their data (including standardization and data sharing) and expertise around common indicators will be necessary to effectively meet the goals of Vision Zero.

Design can be either transferred as knowledge, conveyed as understanding, or only evoked as mood. Engineering students must recapture the enjoyment of making things'' guided by specific human needs and decisions refined by education and experience. (DF)

We exploit information in option prices in order to study whether the ex post responsiveness of stock prices to earnings information is reflected from an ex ante, firm- and quarter-specific perspective. Specifically, we develop a measure of anticipated information content (AIC) that isolates the forecasted magnitude of the stock market’s reaction to earnings information. We find that the AIC positively correlates with the ex post magnitude of the stock market sensitivity to unexpected earnings, increases with earnings persistence, firm growth prospects, the richness of firms’ information environments and the presence of (and changes in) sophisticated ownership, and decreases with discount rates. Our paper sheds light on the role that earnings information plays in shaping option-market behavior and offers researchers an option-market approach to studying the responsiveness of stock prices to earnings information.

Theory suggests that reputations allow nonanonymous markets to attenuate adverse selection in trading. We identify instances in which New York Stock Exchange (NYSE) stocks experience trading floor relocations. Although specialists follow the stocks to their new locations, most brokers do not. We find a discernable increase in liquidity costs around a stock's relocation that is larger for stocks with higher adverse selection and greater broker turnover. We also find that floor brokers relocating with the stock obtain lower trading costs than brokers not moving and brokers beginning trading post-move. Our results suggest that reputation plays an important role in the NYSE's liquidity provision process. KLEIN (1997) DOCUMENTS THAT REPUTATION HAS PLAYED A ROLE in facilitating trade since at least the Middle Ages by reducing information asymmetries between buyers and sellers. Diamond (1991), Boot, Greenbaum, and Thakor (1993), and Wilner (2000) model reputation's role in various financial market settings. Despite its perceived importance, there is little direct empirical evidence as to the economic value of relationships in financial markets. DeJong, Forsythe, and Lundholm (1985) and others find that reputation matters in experimental markets, but it is difficult to generalize these results. Carter and Manaster (1990) find that an underwriter's reputation is associated with returns of initial public equity offerings, but there seems to be no evidence of reputation effects in secondary equity markets.1 Here, we use a natural experiment to evaluate the

In 2001, the Securities and Exchange Commission (SEC) required market centers to publish monthly execution-quality reports in an effort to spur competition for order flow between markets. Using samples of stocks trading on several markets, we investigate whether past execution quality affects order-routing decisions and whether the new disclosure requirements influence this relationship. We find that routing decisions are associated with execution quality; markets reporting low execution costs and fast fills subsequently receive more orders. Moreover, the reports themselves appear to provide information that was unavailable previously. Our results are consistent with active competition for order flow that can be influenced by public disclosure. (JEL G24, G28, K22)

The development of a series of GABA(A) alpha2/alpha3 subtype selective pyridazine based benzodiazepine site agonists as anxiolytic agents with reduced sedative/ataxic potential is described, including the discovery of 16, a remarkably alpha3-selective compound ideal for in vivo study. These ligands are antagonists at the alpha1 subtype, with good CNS penetration and receptor occupancy, and excellent oral bioavailability.

Imidazo[1,2-a]pyrimidines and imidazo[1,2-b][1,2,4]triazines are ligands for the benzodiazepine binding site of GABA(A) receptors that are functionally selective for the alpha2/alpha3 subtypes over the alpha1 subtype. SAR studies to optimise this functional selectivity, pharmacokinetic and behavioural data are described.

We examine the components of displayed (quoted) liquidity and the amount of non-displayed liquidity on the NYSE for a sample of non-US stocks. Consistently with prior work, non-US stocks have less displayed liquidity than similar US stocks. Extending prior research, we find that this is true both in the limit order book and on the floor. As Domowitz et al. [Domowitz, I., Glen, J., Madhavan, A., 1998. International cross-listing and order flow migration: Evidence from and emerging market. Journal of Finance 53, 2001–2027] posit, non-US stocks from transparent/linked home markets have more displayed NYSE liquidity when the home market is open but non-US stocks from opaque/non-linked home markets have more NYSE displayed liquidity when the home market is closed. Non-US and US stocks have similar supplies of non-displayed liquidity, consistent with the idea that the conditional nature of non-displayed liquidity allows NYSE traders to mitigate adverse selection problems inherent in trading non-US stocks. Our results imply that non-US stocks have less total (displayed plus non-displayed) liquidity than US stocks.

In its response to the 1975 Congressional mandate to implement a national market system for financial securities, the Securities and Exchange Commission (SEC) initially exempted the option market. Recent dramatic changes in the structure of the option market prompted the SEC to revisit this issue. We examine a sample of actively traded, multiply listed equity options to ask whether this market’s characteristics appear consistent with the goals of producing economically efficient transactions and facilitating “best execution.” We find marked changes between June 2000, when quotes are often ignored, and January 2002, when the market more closely resembles a national market. EQUITY OPTION TRADING CHANGED dramatically with the beginning of vigorous competition for order flow in many actively traded options during August 1999; the

We use NYSE system order data to conduct a controlled experiment examining changes in trader behavior, displayed liquidity supply, and execution quality around the reduction in the minimum price variation to $0.01. Although traders do not substantially reduce their use of traditional limit orders in favor of market orders or non-displayed orders, they do decrease limit order size and cancel limit orders more frequently after decimals than before. These changes in order submission strategy appear to result in less displayed liquidity throughout the limit order book more than 15 cents from the quote midpoint. This reduction in displayed liquidity, however, does not manifest itself in poor execution quality. Even for large system orders, traditional execution quality is not worse with decimals than with fractions.

The extant execution quality literature generally suggests that brokers routing orders away from the NYSE might not fulfill their fiduciary best execution responsibility. This conclusion is drawn by comparing execution prices across trading venues and presumes that other execution-quality characteristics are equivalent. Using order audit-trail data, we find evidence that retail market orders obtain better trade prices on the NYSE but faster executions, more depth improvement, and order-flow payment at Trimark Securities, a Nasdaq dealer. Thus, non-price dimensions of execution quality are not equivalent across trading venues. Furthermore, considering order flow payments, brokers obtain better net prices with Trimark. If brokers pass enough of these payments through to investors in the form of lower commissions and/or better services, then investors also obtain better net prices with Trimark. Our results suggest that it may be misleading to evaluate execution quality or to base policy decisions on comparisons focusing on only execution prices.

Traditional price improvement improperly assesses large orders’ execution quality by ignoring additional liquidity depth-exceeding orders receive at the quoted price and viewing orders that “walk the book” as “disimproved”. Ignoring this additional liquidity is particularly problematic when assessing execution quality in markets with significant non-displayed liquidity. To correct this deficiency, we modify the price benchmark used to determine whether an order is price improved by making the benchmark a function of the order's size relative to the quoted depth. We document that the differences between conventional price improvement and our measure, adjusted price improvement, can be dramatic and show that the difference depends on trading volume, stock price, and volatility.

We examine the impact deciding to route limit orders away from the New York Stock Exchange (NYSE) has on three dimensions of execution quality with methodologies controlling for market conditions and order submission strategies. Overall differences in limit order execution quality between regional stock exchanges and the NYSE are small, suggesting that the order routing decision may not affect retail limit order traders substantively. Conditioning on the distance between the limit order's price and prevailing quotes, however, reveals systematic differences in execution quality. This implies that brokers can strategically route limit orders to improve retail limit order execution quality. Copyright 2002, Oxford University Press.

An 81-year-old man presented with sudden-onset slurred speech and right-sided weakness commencing 2 hours previously. Initial National Institute of Health Stroke Scale score was 13. Non-contrast CT brain scan excluded haemorrhage, and he received intravenous thrombolysis. Medical history included tissue aortic valve replacement. On arrival, his temperature was 38°C. Two hours after thrombolysis he had two seizures, and his Glasgow Coma Scale score dropped from 15/15 to 6/15 (breakdown: eyes 1, voice 1, motor 4). Repeat CT demonstrated a left middle cerebral artery territory infarct, and he was transferred to the intensive care unit (figure 1 …

We use market-order data to determine execution quality on the NYSE, four regional stock exchanges, and the Nasdaq InterMarket. We examine a sample period after the reduction in the minimum price variation and after the SEC imposed new order-handling rules, and analyze dimensions of execution quality in addition to trade prices. We find that in the postreform environment, the NYSE offers execution prices that are more favorable to the investor. However, the regional exchanges and the InterMarket offer executions that are faster and that more frequently allow investors to execute orders with sizes exceeding the quoted depth at the quoted price.

Benveniste et al. J. Financial Econom. 32 (1992) 61–86 argue that repeatedly dealing with the same brokers allows market makers to know when brokers exploit private information. This suggests that broker identity may allow market makers to differentiate between customers when pricing market-making services even when market makers can provide separate quoted prices for each order size. Estimates of a major Nasdaq dealer's gross trading revenue vary substantively among routing brokers after controlling for order size. Furthermore, these differences exhibit a degree of stability over time. This suggests that market makers may effectively enforce clientele pricing schedules in a world where security prices are quoted without a minimum price variation and the limit order book is available to all market participants.

We study the division of market-making revenue among dealer, broker, and trader. When Knight Securities, a major Nasdaq dealer, interacts with market orders in actively traded stocks during the fourth quarter of 1996, we estimate that its revenue is $0.057 per share. Knight pays brokers at least $0.025 per share (44% of revenue) for orders. To examine whether brokers appear to share these payments with traders, we compare net trading costs (trade price net of commissions) for traders using brokers routing Knight orders with estimated net trading costs for traders using the only discount broker we can determine did not directly receive market-making revenue. We find that the net trading cost of the broker refusing order-flow payments does not dominate the net trading cost of all brokers selling order flow to Knight. This finding suggests that order-flow payments do not unambiguously harm traders and challenges the conclusions of extant studies using only trade prices to assess market quality.

Merrill Lynch's decision to redirect order flow in exchange-listed equity securities from regional exchanges to the New York Stock Exchange (NYSE) provides an opportunity to examine (1) whether order flow affects market makers' spread-setting behavior and (2) whether brokers can capture liquidity-cost differences between market centers for their customers. Merrill's market-order customers appear to obtain better prices on the NYSE than on the regionals. Consistently with market microstructure theory, the NYSE's quoted spread for stocks affected by Merrill's decision falls relative to a control sample and decreases absolutely for a subsample of stocks we believe most sensitive to order-flow distribution. Journal of Economic Literature Classification Numbers: D40, G10.