Pseudo-continuous ASL

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Influence of different isoflurane anesthesia protocols on murine cerebral hemodynamics measured with pseudo-continuous arterial spin labeling

Influence of different isoflurane anesthesia protocols on murine cerebral hemodynamics measured with pseudo-continuous arterial spin labeling

In this work we provide the first comprehensive assessment of CBF and CVR in the mouse brain under different anesthetic regimes using pseudocontinuous ASL‐MRI in C57BL/6 J mice. In particular, given the prevalence and unique perks of isoflurane anesthesia, we compare three distinct isoflurane ‐based protocols: (i) a free‐breathing isoflurane protocol with doses that reflect commonly used isoflurane concentrations in mouse brain MRI studies, 9,19 defined henceforth as the “medium‐dose” protocol; (ii) the protocol described by Wells et al, 18 where a relatively low dose of isoflurane was used for both induction and maintenance, defined henceforth as the “low‐dose” protocol; and (iii) a medium‐dose isoflurane protocol with mechanical ventilation to counteract the respiratory depressive effect. Additionally, we compare the three isoflurane pro- tocols with a medetomidine anesthesia protocol, which is known to be vasoconstrictive. Furthermore, we evaluate the low ‐dose and ventilated isoflurane protocols in a second mouse strain, partly on a C3H/HeJ background, a strain with known respiratory anomalies. 20
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ICA-based denoising for ASL perfusion imaging

ICA-based denoising for ASL perfusion imaging

All scans were acquired using a 3.0T Siemens Verio scanner (Siemens Healthcare, Erlangen, Germany). ASL data were acquired using the following protocol: pseudo-continuous ASL; single-shot EPI readout; TR/ TE 5386/14 m s; 3.4x3.4  4.5 mm; 24 slices using a matrix size 64x64; alternating control and label pairs acquired after 1.8 s of labeling at 5 different post-labeling delays: 400, 800, 1200, 1600, 2000 m s, varied in a looped fashion and repeated 6 times (total volumes acquired 60); background suppression (WET presaturation and two global inversion pulses with timings calculated as per Okell et al. (2013) 6 ); and, total acquisition time ¼ 4 min 30 s. A calibration image with identical readout parameters, but with no background suppression or ASL labelling, was
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Simultaneous measurement of brain perfusion and labeling efficiency in a single pseudo-continuous arterial spin labeling scan

Simultaneous measurement of brain perfusion and labeling efficiency in a single pseudo-continuous arterial spin labeling scan

Arterial spin labeling (ASL) is an MR technique for noninva- sive and quantitative measurement of cerebral blood flow (CBF) by using the arterial blood as an endogenous tracer (1,2). Pseudo-continuous ASL (pCASL) is now the most widely accepted ASL approach mainly due to its high signal-noise-ratio (SNR) and easy implementation on clini- cal MR scanners without the need of additional hardware (3). In principle, the labeling (or inversion) of pCASL is achieved by applying a long series of short RF pulses in combination with a net mean gradient in the slice selection direction that manipulates the phase of the flowing spins resulting in a pseudo-adiabatic, flow-driven inversion. Con- sequently, its efficiency is vulnerable to factors like flow velocity and field inhomogeneities (4,5), and may vary among arteries, scans, and subjects. Careful optimization of the pCASL sequence can minimize such effects (6–8), albeit not prevent them completely. Because the measured CBF values scale linearly with the labeling efficiency, it is one of the most important parameters to estimate to allow accurate CBF quantification of pCASL perfusion scans (3).
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5 Steps to Fluency with Start ASL

5 Steps to Fluency with Start ASL

As the founder of StartASL.com , the leading online resource for ASL and Deaf Culture, Michelle has tremendous insight into this unique community. Michelle earned a Bachelor’s Degree in Deaf Studies, with an emphasis in teaching, from one of the nation’s premier programs at California State University, Northridge.

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Gesture and ASL L2 Acquisition 1

Gesture and ASL L2 Acquisition 1

might be possible to devise strategies to tap into this pre-existing visual-spatial knowledge in order to facilitate the acquisition of the use of space in ASL. Although, to our knowledge, there are no previous studies that look systematically at manual co-speech gesture as a predictor for ASL aptitude, McIntire & Snitzer Reilly (1988) examined whether the communicative facial expressions that are naturally used by people who use a spoken language are transferred into ASL facial grammar. Their study concludes that while preexisting affective facial expression does serve as a transition in acquiring non-manual grammar in ASL, the learner must first go through a reanalysis stage in which previous knowledge is processed as being linguistically meaningful. This reanalysis process seems to be necessary both for adults L2 learners and for infant L1 learners.
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Detection of Major ASL Sign Types in Continuous Signing For ASL Recognition

Detection of Major ASL Sign Types in Continuous Signing For ASL Recognition

This is a first step towards creating a complete system for real-time sign recognition that leverages the linguistic prop- erties of the distinct sign classes. Incorporation of such linguistic information would 1) lead to improvements in the segmentation itself, and 2) be used for sign identifica- tion within the segmented regions. There is considerable research on recognition strategies for fingerspelled signs (Rioux-Maldague and Giguere, 2014; Kim et al., 2013; Pugeault and Bowden, 2011; Ricco and Tomasi, 2009, e.g.). For lexical signs, linguistic constraints on the rela- tionships between the start and end handshapes of a given sign, and between the handshapes used on the left and right hands, have already been demonstrated to improve accu- racy of handshape recognition (a crucial linguistic com- ponent) (Dilsizian et al., 2014). Work is now in progress on incorporating 3D tracking of hands, arms, and upper body to exploit the motion properties of lexical signs for sign identification (Dilsizian et al., 2016). This approach, sensitive to the fundamentally different internal structure of distinct sign types, holds great promise for recognition of large-scale vocabulary from continuous signing.
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Unsupervised Learning of Prosodic Boundaries in ASL

Unsupervised Learning of Prosodic Boundaries in ASL

UNSUPERVISED LEARNING OF PROSODIC BOUNDARIES IN ASL 61 8 Conclusion We have offered the first unsupervised systems to learn aspects of prosodic phrasing in a sign lan- guage. Both unsupervised systems recover reasonable parameters and have predictive performance on par with supervised systems, but adding a dependency between adjacent states does not improve performance. Furthermore, the overall predictive performance of even the supervised system is lower than what has previously been reported for similar models applied to English. One possible explanation is differences between the data sets, such as the more formal production of radio speech or the high rate of constructed action in the narratives, which may show similar cues to phrase-final signs. Another confound comes from the additional part-of-speech information available in previ- ous research on English but unavailable in our study. Perhaps the most exciting possibility is that additional cues or more complex combinations of known cues can mark prosodic phrasing. While further work on I-phrase final cues in ASL is necessary, the success of such simple systems at deter- mining cue distributions sheds light on how infants might learn the prosodic system without explicit instruction.
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ASL, second generation application management

ASL, second generation application management

In the present hectic time on the market and in organizations is hard to gain a clear understanding into the desired ICT-support on long term (10 years). Therefore, there is little sense in the design of a complete blueprint for the ICT-structure. The emphasis should be on a stepwise growth path from the existing situation to a new situation, which will probably be changed after a couple of years on its turn. The scope of the ACM, Applications Cycle Management, processes that are defined in ASL is the next 3-5 years. They can lead tot improvement activities on a comparable or even longer term.
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ASL and DSC MRI of brain tumors

ASL and DSC MRI of brain tumors

Abstract : Purpose : Arterial spin labeling (ASL) is an alternative method to Dynamic susceptibility contrast (DSC) perfusion MRI for brain tumors. However, ASL cerebral blood flow (CBF) can be easily affected by transit time. DSC MRI derived time to maximum of the residue function (Tmax) is possible to assess the transit time on ASL. Methods : Thirty patients with brain tumors were studied using ASL and DSC MRI. The relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), Tmax, and mean transit time (MTT) were obtained from DSC MRI. The ratios of the parameters were analyzed. Results : ASL CBF ratio correlated with the DSC rCBF ratio (r = 0.78, p 0.001) and rCBV ratio (r = 0.74, p 0.001). There was a moderate correlation between ASL CBF ratio and Tmax ratio (r = -0.43, p 0.05) in brain tumors. Conclusions : ASL CBF strongly correlated with DSC rCBF and rCBV. In addition, a negative correlation was found between ASL CBF and Tmax in brain tumors, indicating that these parameters would be affected by transit time. This may explain why ASL CBF is different from DSC rCBF and rCBV. The decreased DSC Tmax value may suggest high vascularity in a tumor. J. Med. Invest. 63 : 175-181, August, 2016
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ASL Lesson Plans for the Deaf Classroom

ASL Lesson Plans for the Deaf Classroom

The province of British Columbia International Curriculum guide reports that approximately 10 percent of the population of North America has some degree of hearing loss (and, for many of these people, ASL is the language of choice), it is likely that students will encounter someone whose language is ASL. ASL is a complete and complex language with its own grammatical rules and syntax, which are not based on, nor derived from, any spoken or written language. It is one of the many sign languages used around the world. ASL, like the majority of world languages, has no written form. It is an integral part of North American Deaf culture and community. Individuals who are deaf have traditionally been seen by non-deaf people as members of a disabled group. However, Deaf culture values deafness not as a disability but rather as a characteristic of a community’s cohesive cultural identity. A key feature of this cohesive culture is its language, ASL. Since the work of the linguist William Stokoe in 1960, ASL has been recognized as a complex rule-governed visual language. Deaf culture, like all cultures, is based on a community of people who use the same language to communicate, and ASL reflects the values and norms for interaction within that cultural language group.
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American Sign Language and ASL Linguistics

American Sign Language and ASL Linguistics

A group of Deaf people who uses American Sign Language, lives by a set of norms and values of the Deaf community, shares the Deaf heritage and traditions, and involves as a member of [r]

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Russia and the IMF: pseudo lending for pseudo reforms

Russia and the IMF: pseudo lending for pseudo reforms

Failure to regain macro-economic stability during the first years after liberalisation attracted sharp criticism of the IMF from various quarters. This is not to say that the successive Russian governments are immune of criticism. Their chief fault lies in the chronic refusal to reform. In addition, reluctance of the G7 to get involved in reforms and provide financial assistance to Russia when most needed is equally to blame. Moreover, a snail pace of the World Bank involvement also contributed to failure. Even so, both, the Russian government and the IMF, were accused of squandering one after another opportunity to stabilise Russia with disastrous consequences for the welfare of the Russian people. Critics charged that these two, of which the IMF was a typical representative of the West, have never missed opportunity to miss opportunity in Russia (Sachs, 1997). During this time, a common understanding between the West and the Russian government, via the IMF, was maintained. The West would pretend to aid the Russians while they would pretend to stabilise (Granvile, 1995). Likewise, IMF promised loans and Russian government promised reforms. This turned out to be a pseudo lending for pseudo reforms.
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Demonstration of pseudo-ductility in unidirectional hybrid composites made of discontinuous carbon/epoxy and continuous glass/epoxy plies

Demonstration of pseudo-ductility in unidirectional hybrid composites made of discontinuous carbon/epoxy and continuous glass/epoxy plies

composites was usually observed in the form of a significant load drop at the low strain fibre failure in unidirectional (UD) interlayer hybrid composites, which is the baseline for improvement in this study. The most straightforward interply (or interlayer) hybridi- sation [5] was performed within this study because this method showed promising scope for pseudo-ductility [13] and it can be rea- lised using existing prepreg materials which keeps specimen manufacturing simple. Strong potential for demonstrating pseu- do-ductility while maintaining high performance in UD composites was shown earlier by the authors [13–15] using emerging thin ply prepregs to suppress delamination in interlayer hybrid configura- tions. The main focus of researchers investigating thin-ply compos- ites was to explore the change in damage modes due to more dispersed lay-up designs [16–18]. Their main conclusion is that the onset of damage is delayed in thin-ply composites because pre- mature matrix cracking and delaminations can be suppressed due to the low energy release rate of thin plies in static loading, but the final failure in general becomes more brittle. Thin-ply laminates also show less interlaminar but more fibre damage under impact [19]. The suppression of delaminations can be exploited in thin- ply UD interlayer hybrid composites [13] to make the pull-out of the broken low strain material stable. One issue with the thin ply hybrids presented in [13] is, that the resulting carbon/glass volume ratio is relatively low if the thickness limit of around 85 l m for that specific material combination is kept and standard thickness glass plies are used. In order to overcome this limitation, a UD partially discontinuous architecture with a discontinuous carbon and continuous glass layers is proposed here which will be called the discontinuous hybrid configuration in the rest of the paper. The
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New Types of Pseudo Ideals in Pseudo Q-algebra

New Types of Pseudo Ideals in Pseudo Q-algebra

Neggers J., Ahn. S. S., Kim H. S., at 2001 introduced the class of Q-algebras, (1). Georgescu G. and Iorgulescu A., at the same time introduced pseudo BCK-algebras as an extension of BCK- algebras, (2). Dudek. W. A. and Jun. Y. B., at 2008 introduced pseudo BCI-algebras as a natural generalization of BCI-algebras and of pseudo BCK- algebras, (3). Walendziak A., at 2015 defined pseudo BCH-algebras and considered ideals in such algebras, (4). Jun. Y. B., Kim. H. S. and Ahn. S.S., at 2016 introduced pseudo Q-algebra as a generalization of Q-algebra, and structures of pseudo ideal and pseudo atom in a pseudo Q- algebra, (5). The aim of this paper is to introduce new types of pseudo ideals and also some of theorems and we make clear it relationships with pseudo ideal in pseudo Q-algebra.
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Running head: FINGERSPELLING IN ASL DISCOURSE 1

Running head: FINGERSPELLING IN ASL DISCOURSE 1

When fingerspelling is rapid, individual letters are not crisply articulated usually because of increased speed. Letters may not become fully formed and may assimilate into one another or into the handshape of a surrounding sign. Rapid fingerspelling usually occurs if a fingerspelled word is repeated in a communication event. The first time it is produced carefully, but once the audience recognizes it, it may be produced rapidly. The shape and movement will be maintained so the word is still recognizable even if letters are assimilated and produced hastily (Ross, 2004). Rapid fingerspelling may be difficult for students of ASL and interpreters to perceive without practice. If attention is paid to catch the shape and movement of the initial careful fingerspelling, provided this is intentionally articulated, reception and comprehension will be easier.
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On Pseudo Regular and Pseudo Irregular Bipolar Fuzzy Graphs

On Pseudo Regular and Pseudo Irregular Bipolar Fuzzy Graphs

Abstract. In this paper, pseudo regular bipolar fuzzy graphs, pseudo irregular bipolar fuzzy graphs, highly pseudo irregular bipolar fuzzy graphs, totally pseudo regular bipolar fuzzy graphs, pseudo totally irregular bipolar fuzzy graphs, highly pseudo totally irregular bipolar fuzzy graphs are introduced and some properties of its properties are discussed.

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Motivation and second language learning: Implications for ASL

Motivation and second language learning: Implications for ASL

Motivation and Second Language Research Related to the study of L2 learning, motivation is defined by Gardner as, "the combination of effort plus desire to achieve the goal of learning t[r]

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The Acquisition of Synonyms in American Sign Language (ASL): Toward a Further Understanding of the Components of ASL Vocabulary Knowledge

The Acquisition of Synonyms in American Sign Language (ASL): Toward a Further Understanding of the Components of ASL Vocabulary Knowledge

The current results are in line with previous studies showing that DCHP who are not exposed to good language models at an early age are at risk of reduced language ability in ASL (Mayberry, Lock, and Kazmi 2002; Mayberry 1992; Mayberry and Eichen 1991). Our results further indicate that compensating for this deficit is difficult even after years of ASL exposure and use in adulthood. These findings raise the question of how consistent and rich the ASL input is for Deaf children in the educational system. One could argue that DCHP are not proficient in ASL and that English is instead their dominant language. These results do not support this assumption, however, as the performance on the synonym task was found to correlate with that of reading comprehension of English (r = 0.51, p < .01) (Hoffmeister 2000), showing that the DCHP did not perform better in English than they did in ASL. These results show the critical importance for Deaf children of early language input that consists of consistent and high-quality sign language.
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ASL Camguard Introduces a Full Range of Products.

ASL Camguard Introduces a Full Range of Products.

It’s the start of a new year and new chapter for CamGuard users. ASL has introduced an expanded line of CamGuard products tailored to enhance automobile, marine and small engine oils. It seems many pilots use CamGuard Aviation in their other engines anyway, so Ed Kollin, ASL’s technical guru, formulated the optimum CamGuard blend for each of these applications.

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COST AID ASL post- processing Workshop

COST AID ASL post- processing Workshop

Now   we   have   a   relative   perfusion   image   we   want   to   do   some   very   basic   quantification.  For  this  we  will  use  a  separate  calibration  image  (calibhead)  that   was   acquired   using   exactly   the   same   parameters   as   the   ASL   data,   but   with   a   longer  TR  (6  s  in  this  case)  and  no  background  suppression  (assuming  that  it  was   applied  to  the  main  data):  

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