Miracle-dz/UniFAR-FTUs huggingface dataset:
Corrective feedback to spoken errors in adult ESL classrooms

This study investigates the attitudes and practice of second language teachers in regard to corrective feedback on learners' spoken errors. In particular, it examines frequency and types of corrective feedback to adult learners of English as a second language in a Melbourne language centre. It relates individual teachers' patterns of corrective feedback to the context of the teaching program and to teachers' attitudes to second language learning and teaching. The study is based mainly on observational classroom data and interviews. Ten lessons, each averaging fifty minutes in length, were recorded over a period of seven months. Two kinds of classes were observed, five classes for immigrant learners and five classes for international student learners. The five teachers who taught the classes were interviewed during the period of lesson recordings. Lesson analysis is based on the Error Treatment Sequence (Lyster and Ranta 1997). Results of this study are compared with those found by Lyster and Ranta in their study of corrective feedback in French immersion classrooms. The key similarity of the two studies lies in the proportion of different types of feedback. In particular, the recast occurs as the most commonly used feedback type in both studies. The key difference between the results of the two studies is in the relative frequency of corrective feedback. Learner errors are given feedback only about half as frequently in this study as in the immersion study. Possible reasons for this difference are discussed. Detailed interviews with teachers in the study show that teachers' attitudes are mostly predictive of their classroom practice, and that teachers' background and experience can be related to their attitudes. The study supports the revised version of the Interaction Hypothesis (Long 1996) in showing that corrective feedback exists in usable form in instructed settings, and that learners make use of it.
Comparison of Intraarterial and Intravenous Thrombolysis for Ischemic Stroke With Hyperdense Middle Cerebral Artery Sign

Background and Purpose— It is unclear whether intraarterial (IAT) or intravenous (IVT) thrombolysis is more effective for ischemic stroke with hyperdense middle cerebral artery sign (HMCAS) on computed tomography (CT). The aim of this study was to compare IAT and IVT in stroke patients with HMCAS. Methods— Comparison of data from 2 stroke units with similar management of stroke associated with HMCAS, except that 1 unit performed IAT with urokinase and the other IVT with plasminogen activator. Time to treatment was up to 6 hours for IAT and up to 3 hours for IVT. Outcome was measured by mortality and the modified Rankin Scale (mRS), dichotomized at 3 months into favorable (mRS 0 to 2) and unfavorable (mRS 3 to 6). Results— One hundred twelve patients exhibited a HMCAS, 55 of 268 patients treated with IAT and 57 of 249 patients who underwent IVT. Stroke severity at baseline and patient age were similar in both groups. Mean time to treatment was longer in the IAT group (244±63 minutes) than in the IVT group (156±21 minutes; P=0.0001). However, favorable outcome was more frequent after IAT (n=29, 53%) than after IVT (n=13, 23%; P=0.001), and mortality was lower after IAT (n=4, 7%) than after IVT (n=13, 23%; P=0.022). After multiple regression analysis IAT was associated with a more favorable outcome than IVT (P=0.003) but similar mortality (P=0.192). Conclusion— In this observational study intraarterial thrombolysis was more beneficial than IVT in the specific group of stroke patients presenting with HMCAS on CT, even though IAT was started later. Our results indicate that a randomized trial comparing both thrombolytic treatments in patients with middle cerebral artery occlusion is warranted.
Fitness consequences of occasional outcrossing in a functionally asexual plant (Oenothera biennis).

Many clonal organisms occasionally outcross, but the long-term consequences of such infrequent events are often unknown. During five years, representing three to five plant generations, we followed 16 experimental field populations of the forb, Oenothera biennis, originally planted with the same 18 original genotypes. Oenothera biennis usually self fertilizes, which, due to its genetic system (permanent translocation heterozygosity), results in seeds that are clones of the maternal plant. However, rare outcrossing produces genetically novel offspring (but without recombination or increased heterozygosity). We sought to understand whether novel genotypes produced through natural outcrossing had greater fecundity or different multigenerational dynamics compared to our original genotypes. We further assessed whether any differences in fitness or abundances through time between original and novel genotypes were exaggerated in the presence vs. absence of insect herbivores. Over the course of the experiment, we genotyped >12,500 plants using microsatellite DNA markers to identify and track the frequency of specific genotypes and estimated fecundity on a subset (>3,000) of plants. The effective outcrossing rate was 7.3% in the first year and ultimately 50% of the plants were of outcrossed origin by the final year of the experiment. Lifetime fruit production per plant was on average 32% higher across all novel genotypes produced via outcrossing compared to the original genotypes, and this fecundity advantage was significantly enhanced in populations lacking herbivores. Among 43 novel genotypes that were abundant enough to phenotype with replication, plants produced nearly 30% more fruits than the average of their specific two parental genotypes, and marginally more fruits (8%) than their most fecund parent. Mean per capita fecundity of novel genotypes predicted their relative frequencies at the end of the experiment. Novel genotypes increased more dramatically in herbivore-present compared to suppressed populations (45% vs. 27% of all plants), countering the increased competition from dandelions (Taraxacum officinale) that resulted from herbivore suppression. Increased interspecific competition likely also lead to the lower realized fitness of novel vs. original genotypes in herbivore-suppressed populations. These results demonstrate that rare outcrossing and the generation of novel genotypes can create high-fecundity progeny, with the biotic environment influencing the dynamical outcome of such advantages.
Remission rate after thymectomy in myasthenia gravis when the bias of immunosuppressive therapy is eliminated

The clinical course of all 86 myasthenia gravis (MG) patients who were thymectomised at Sahlgrenska Hospital between 1955 and 1980 was evaluated in order to estimate what the rate of complete clinical remission (with or without anticholinesterase medication) would be without immunosuppressive (IS) therapy; 19 of 73 patients without thymoma received IS therapy. A suitable way of dissociating the course after thymectomy from the influence of IS therapy is the Markov method. The calculated probability of remission was 0.18, 0.35, 0.43, 0.53 and 0.56 in the 0–1, 2–3, 4–5, 5–10 and more than 10‐year periods after thymectomy. A similar result (53 ± 7%) was obtained by a life‐table method with censoring of IS‐treated patients when they received such therapy. Time to remission was significantly shorter for patients with age of MG onset before 35 years. Timing of IS therapy after thymectomy is discussed, considering the post‐thymectomy remission rate.
An Efficient Controller for SV-PWM VSI Based on the Multivariable Structure Function

In this paper a novel control strategy for pulse-widh modulated voltage source inverters (PWM VSI) is presented. It is based on a linear, diagonal, low order, minimum-phase, fixed, and stable multivariable controller. It is obtained via individual channel design (ICD), a new framework that allows analysis and synthesis of multivariable control systems by means of the multivariable structure function (MSF). Such controller generates the appropriate reference voltage signals for the power inverter via a space-vector PWM (SV-PWM), which in turn provides the voltage signals for the terminals of an induction motor. The theoretical principles behind this control strategy are summarised for completeness. The similarities and differences between some current loop controllers found in literature and the scheme here proposed are discussed. In order to show the ICD controller performance a digital simulation is included. Moreover, it is also shown through the MSF that the dynamical system structure is not sensible to rotor speed or parameter variations. Therefore, it is possible to design a fixed linear robust controller for the whole speed range. Such solution is feasible for engineering applications due to its simplicity and robustness.
Which Firms Follow the Market? An Analysis of Corporate Investment Decisions

We test whether stock market mispricing or private investor information in stock prices affects corporate investment. We develop an econometric methodology that disentangles stock-price movements that are relevant for investment from those that are not. We combine this decomposition with proxies for private information and mispricing to devise unbiased tests for the effects of mispricing and information on investment. We depart from much of the literature by finding that stock market mispricing does not affect investment, especially that of large firms and firms subject to mispricing. In contrast, we confirm previous evidence that managers incorporate private investor information when making investment decisions. The Author 2010. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org. , Oxford University Press.
Online Markov Decision Processes With Kullback–Leibler Control Cost

This paper considers an online (real-time) control problem that involves an agent performing a discrete-time random walk over a finite state space. The agent's action at each time step is to specify the probability distribution for the next state given the current state. Following the setup of Todorov, the state-action cost at each time step is a sum of a state cost and a control cost given by the Kullback-Leibler (KL) divergence between the agent's next-state distribution and that determined by some fixed passive dynamics. The online aspect of the problem is due to the fact that the state cost functions are generated by a dynamic environment, and the agent learns the current state cost only after selecting an action. An explicit construction of a computationally efficient strategy with small regret (i.e., expected difference between its actual total cost and the smallest cost attainable using noncausal knowledge of the state costs) under mild regularity conditions is presented, along with a demonstration of the performance of the proposed strategy on a simulated target tracking problem. A number of new results on Markov decision processes with KL control cost are also obtained.
Common Risk Factors in Currency Markets

We identify a "slope" factor in exchange rates. High interest rate currencies load more on this slope factor than low interest rate currencies. This factor accounts for most of the cross-sectional variation in average excess returns between high and low interest rate currencies. A standard, no-arbitrage model of interest rates with two factors--a country-specific factor and a global factor--can replicate these findings, provided there is sufficient heterogeneity in exposure to global or common innovations. We show that our slope factor identifies these common shocks, and we provide empirical evidence that it is related to changes in global equity market volatility. By investing in high interest rate currencies and borrowing in low interest rate currencies, U.S. investors load up on global risk. The Author 2011. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com. , Oxford University Press.
Chemokines, selectins and intracellular calcium flux: temporal and spatial cues for leukocyte arrest

Leukocyte trafficking to acute sites of injury or infection requires spatial and temporal cues that fine tune precise sites of firm adhesion and guide migration to endothelial junctions where they undergo diapedesis to sites of insult. Many detailed studies on the location and gradient of chemokines such as IL-8 and other CXCR ligands reveal that their recognition shortly after selectin-mediated capture and rolling exerts acute effects on integrin activation and subsequent binding to their ligands on the endothelium, which directs firm adhesion, adhesion strengthening, and downstream migration. In this process, G-protein coupled receptor (GPCR) signaling has been found to play an integral role in activating and mobilizing intracellular stores of calcium, GTPases such as Rap-1 and Rho and cytokeletal proteins such as Talin and F-actin to facilitate cell polarity and directional pseudopod formation. A critical question remaining is how intracellular Ca2+ flux from CRAC channels such as Orai1 synergizes with cytosolic stores to mediate a rapid flux which is critical to the onset of PMN arrest and polarization. Our review will highlight a specific role for calcium as a signaling messenger in activating focal clusters of integrins bound to the cytoskeleton which allows the cell to attain a migratory phenotype. The precise interplay between chemokines, selectins, and integrins binding under the ubiquitous presence of shear stress from blood flow provides an essential cooperative signaling mechanism for effective leukocyte recruitment.
Hormonal control of growth in the infant rat.

To obtain information on pituitary control of growth in infant rats, we employed a hypophysectomy technique which can be used on 4- to 6-day-old pups with an 80% success rate. A 30–50% reduction in body weight gain and a 30–40% decrease in tail growth were observed in the pups after hypophysectomy. The following hormone replacement injections were administered from days 7–15: ovine GH (oGH) or PRL (oPRL), at 1 or 4 μg/g BW, alone and in combination; T4 (40 ng/g for 4 days then 8 ng/g for 4 days) alone or in combination with the low dose of oPRL and/or oGH; and rat pituitary homogenate at 10 and 100 jug wet weight/g BW. Neither dose of oPRL increased weight gain or tail growth significantly. The high dose of oGH restored body weight gain and tail growth to 95% and 80%, respectively, of that in the sham controls. The low dose of GH increased both parameters to 75% of the sham values. Responses to injections of PRL and GH combined were intermediate between those of the hormones alone. T4 alone had no effect .
Vitamin Supplementation as Possible Prophylactic Treatment against Migraine with Aura and Menstrual Migraine

Migraine is the most common form of headache disorder globally. The etiology of migraine is multifactorial, with genetic components and environmental interactions considered to be the main causal factors. Some researchers postulate that deficits in mitochondrial energy reserves can cause migraine or an increase in homocysteine levels can lead to migraine attacks; therefore, vitamins could play a vital role in migraine prevention. For instance, riboflavin influences mitochondrial dysfunction and prevents migraine. Genes such as flavoenzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), especially the C677T variant, have been associated with elevated plasma levels of homocysteine and migraine with aura. Homocysteine catalyzation requires the presence of vitamins B6, B12, and folic acid, which can decrease the severity of migraine with aura, making these vitamins potentially useful prophylactic agents for treating migraine with aura. Menstrual migraine, on the other hand, is associated with increased prostaglandin (PG) levels in the endometrium, indicating a role for vitamin E, which is an anti-PG. Vitamin C can also be used as a scavenger of reactive oxygen species for treating neurogenic inflammation in migraine patients. This paper reviews possible therapies based on vitamin supplementation for migraine prophylaxis, focusing on migraine with aura and menstrual migraine.
Acute abdominal aortic aneurysms: cost analysis of endovascular repair and open surgery in hemodynamically stable patients with 1-year follow-up.

PURPOSE To retrospectively assess the in-hospital and 1-year follow-up costs of endovascular aneurysm repair and conventional open surgery in patients with acute infrarenal abdominal aortic aneurysm (AAA) by using a resource-use approach. MATERIALS AND METHODS Institutional Review Board approval was obtained, and informed consent was waived. In-hospital costs for all consecutive patients (61 men, six women; mean age, 72.0 years) who underwent endovascular repair (n = 32) or open surgery (n = 35) for acute infrarenal AAA from January 1, 2001, to December 31, 2004, were assessed by using a resource-use approach. Patients who did not undergo computed tomography before the procedure were excluded from analysis. One-year follow-up costs were complete for 30 patients who underwent endovascular repair and for 34 patients who underwent open surgery. Costs were assessed from a health care perspective. Mean costs were calculated for each treatment group and were compared by using the Mann-Whitney U test (alpha = .05). The influence of clinical variables on the total in-hospital cost was investigated by using univariate and multivariate analyses. Costs were expressed in euros for the year 2003. RESULTS Sex, age, and comorbidity did not differ between treatment groups (P > .05). The mean total in-hospital costs were lower for patients who underwent endovascular repair than for those who underwent open surgery (euro20 767 vs euro35 470, respectively; P = .004). The total costs, including those for 1-year follow-up, were euro23 588 for patients who underwent endovascular repair and euro36 448 for those who underwent open surgery (P = .05). The results of multivariate analysis indicated that complications had a significant influence on total in-hospital cost; patients who had complications incurred total in-hospital costs that were 2.27 times higher than those for patients who had no complications. CONCLUSION Total in-hospital costs and total overall costs, which included 1-year follow-up costs, were lower in patients with acute AAA who underwent endovascular repair than in those who underwent open surgery.
A Geometry Study on the Capacity of Wireless Networks via Percolation

We study the effect of various geometries on the capacity of wireless networks via percolation, which was not considered much before. Percolation theory was first applied to derive an achievable rate 1/√n in [5] by constructing a highway system, in contrast with the previous result Θ(1/√n log n) in [6], where n is the number of the nodes. While a highway system that consists of both horizontal and vertical edge-disjoint paths exists in a square network, B. Liu et al. in [1] pointed out that the horizontal paths will disappear if the width of a strip network is increasing more slowly than \log n. In this paper, first we take a deeper look at the percolation in a strip network. We discover that when a highway system exists, the capacity is restricted by the maximum length of the sides. Moreover, a sub-highway system is still in presence when the highway system disappears. Secondly, we consider the situations in a triangle network. Conditions that percolation highway exists in it, and the achievable rate for a triangle network are discussed. We find that corner effect can be a bottleneck of the capacity. By combining the achievable rate of the former networks, we attribute the variance between them to their symmetry discrepancies. Finally, we turn to the capacity of three dimensional (3D) networks via percolation. The whole study shows that geometric symmetry plays a significant role in the percolation and the capacity, thereby shedding a light on the network design and the scheduling.
Geometric Langlands in prime characteristic

Let $G$ be a semi-simple algebraic group over an algebraically closed field $k$ , whose characteristic is positive and does not divide the order of the Weyl group of $G$ , and let $\breve{G}$ be its Langlands dual group over $k$ . Let $C$ be a smooth projective curve over $k$ of genus at least two. Denote by $\operatorname{Bun}_{G}$ the moduli stack of $G$ -bundles on $C$ and $\operatorname{LocSys}_{\breve{G}}$ the moduli stack of $\breve{G}$ -local systems on $C$ . Let $D_{\operatorname{Bun}_{G}}$ be the sheaf of crystalline differential operators on $\operatorname{Bun}_{G}$ . In this paper we construct an equivalence between the bounded derived category $D^{b}(\operatorname{QCoh}(\operatorname{LocSys}_{\breve{G}}^{0}))$ of quasi-coherent sheaves on some open subset $\operatorname{LocSys}_{\breve{G}}^{0}\subset \operatorname{LocSys}_{\breve{G}}$ and bounded derived category $D^{b}(D_{\operatorname{Bun}_{G}}^{0}\text{-}\text{mod})$ of modules over some localization $D_{\operatorname{Bun}_{G}}^{0}$ of $D_{\operatorname{Bun}_{G}}$ . This generalizes the work of Bezrukavnikov and Braverman in the $\operatorname{GL}_{n}$ case.
Reproducibility and Validity of the Myotest for Measuring Step Frequency and Ground Contact Time in Recreational Runners

Abstract The purpose of this study was to assess the reproducibility (test-retest reliability and agreement) and concurrent validity of the Myotest for measuring step frequency (SF) and ground contact time (GCT) in recreational runners. Based on a within-subjects design (test and retest), SF and GCT of 14 participants (11 males, 3 females) were measured at three different running speeds with the Myotest during two test sessions. SF and GCT were also assessed with a foot-mounted accelerometer (Gold Standard, previously validated by comparing to force plate data) during the first test session. Levels of test-retest reliability and concurrent validity were expressed with intraclass correlation coefficients (ICC), agreement with standard errors of measurement (SEM). For SF, test-retest reliability (ICC’s > 0.75) and agreement of the Myotest were considered as good at all running speeds. For GCT, test-retest reliability was found to be moderate at a running speed of 14 km/h and poor at speeds of 10 and 12 km/h (ICC < 0.50). Agreement of the Myotest for GCT at all three running speeds was considered not acceptable given the SEM’s calculated. Concurrent validity of the Myotest with the foot-mounted accelerometer (Gold Standard) at all three running speeds was found to be good for SF (ICC’s > 0.75) and moderate for GCT (0.50 < ICC’s < 0.75). The conclusion of our study is that estimates obtained with the Myotest are reproducible and valid for SF but not for GCT.