Novel, congenital iliac arterial anatomy: Absent common iliac arteries and left internal iliac artery.

Congenital anomalies of the iliac arterial system are rare and can be associated with ischemia. With an increase in vascular imaging and interventions, such anomalies are likely to be encountered with greater frequency. We present the case of a 25-year-old female who was incidentally found to have absence of the common iliac arteries bilaterally and the left internal iliac artery, a constellation not previously reported in the literature. We present relevant imaging findings, review embryonic vascular development, and discuss potential clinical implications

The impact of tax policy on corporate debt in a developing economy: A study of unquoted Indian companies

Taxation has potentially important implications for corporate behaviour. However, there have been few studies of the impact of taxation on companies in developing countries, and fewer still concerned with unquoted companies. In this paper, we study the impact of tax policy on the financial decisions of a sample of unquoted companies in India during the period 1989-99 when tax rates were generally reduced as part of a wider programme of financial liberalization. We examine the impact of the tax regime on company financing decisions, within the context of a model of company leverage, controlling for non-tax influences suggested by the theory of corporate finance. The analysis is carried out using a balanced panel consisting of the published accounts of 97 Indian unquoted companies which reported continuously during 1989-99. The model is estimated using GMM. Estimates of the impact of the 1990s tax reforms are derived, and implications for policy are drawn.India, corporate finance, taxation

The variational solution of the problem of plane poiseuille flow with flexible walls

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Counting, Fanout, and the Complexity of Quantum ACC

We propose definitions of \QAC^0, the quantum analog of the classical class \AC^0 of constant-depth circuits with AND and OR gates of arbitrary fan-in, and \QACC[q], the analog of the class \ACC[q] where \Mod_q gates are also allowed. We prove that parity or fanout allows us to construct quantum \MOD_q gates in constant depth for any $q$, so \QACC[2] = \QACC. More generally, we show that for any $q,p > 1$, \MOD_q is equivalent to \MOD_p (up to constant depth). This implies that \QAC^0 with unbounded fanout gates, denoted \QACwf^0, is the same as \QACC[q] and \QACC for all $q$. Since \ACC[p] \ne \ACC[q] whenever $p$ and $q$ are distinct primes, \QACC[q] is strictly more powerful than its classical counterpart, as is \QAC^0 when fanout is allowed. This adds to the growing list of quantum complexity classes which are provably more powerful than their classical counterparts. We also develop techniques for proving upper bounds for \QACC^0 in terms of related language classes. We define classes of languages \EQACC, \NQACC and \BQACC_{\rats}. We define a notion of $\log$-planar \QACC operators and show the appropriately restricted versions of \EQACC and \NQACC are contained in \P/\poly. We also define a notion of $\log$-gate restricted \QACC operators and show the appropriately restricted versions of \EQACC and \NQACC are contained in \TC^0

Improving Canada's Immigration Policy

As labour markets change, the question arises whether Canada’s immigration policy – and our “point system” in particular – is doing a good job of identifying potential immigrants who will fare well on arrival in Canada.economic growth and innovation, immigration point system, Canadian immigration policy

The Impact of the Suspension of Opening and Closing Call

A hotly debated issue in the market microstructure literature is the effectiveness of call auctions as against continuous trading systems. In this paper we investigate this issue by studying the impact of the suspension of opening and closing call auctions by the National Stock Exchange of India in 1999. We compare the volatility, efficiency and liquidity (VEL) of securities in the market before and after suspension, and estimate the value of the auctions to traders by carrying out an event study. Contrary to expectation, we find that VEL factors improved following the suspension, and the CARs were significant but were not uniformly positive or negative. As a partial explanation for these results, we find that less liquid stocks traded less in the auctions than did other securities, especially at the opening, and they experienced the most gains following the suspension. This suggests that less liquid stocks did not gain the expected benefits from the auctions, and therefore that it cannot be assumed that a call auction system will improve share trading in a less liquid emerging market. Future research in this area will need to pay attention to the composition of the shares being traded and to the nature of the trading process in different shares in the market.Call Auctions, stock markets, National Stock Exchange of India

An Analysis of the Impacts of Non-Synchronous Trading On

The serial correlation effects which non-synchronous trading can induce in financial data have been documented by various researchers. In this paper we investigate non-synchronous trading effects in terms of the predictability that may be induced in the values of stock indices. This analysis is applied to emerging-market data, on the grounds that such markets might be less liquid and thus prone to a higher degree of non- synchronous trading. We use both a daily data set and a higher frequency one, since the latter is a prerequisite for capturing intra-day variations in trading activity. When considering one-minute interval data, we obtain clear evidence of predictability between indices with different degrees of non-synchronous trading. We then propose a simple test to infer whether such predictability is mainly attributable to non- synchronous trading or an actual delayed adjustment on part of traders. The results obtained from an intra-day analysis suggest that the former cause seems a better explanation for the observed predictability. Future research in this area is needed to shed light on the degree of data predictability which may be exclusively attributed to non-synchronous trading, and how empirical results may be influenced by the chosen data frequency.Non-Synchronous Trading, Stock Markets, National Stock Exchange of India, High-Frequency Data.