Behavioral and genetic color vision evaluation of an albino male capuchin monkey (Sapajus apella).

Albinism is a rare phenotype that affects the pigmentation in eyes, hair, and skin. The effects of albinism in color vision are still unclear. Our study aimed to evaluate the color vision phenotype and genotype of an albino capuchin monkey. An adult albino male capuchin monkey (Sapajus apella) had the L and M opsin gene analyzed, and was trained in a behavioral task of color discrimination. Color discrimination thresholds were determined along 20 chromatic axes around the background chromaticity. A color discrimination ellipse was drawn by interpolation among these thresholds. The albino monkey's behavioral color discrimination ellipse showed poor discrimination along the red-green axis indicating a deutan phenotype. Genetic analysis revealed only the presence of the L gene in the albino monkey. This result did not differ from that obtained with ten previously tested non-albino monkeys. Behavioral and molecular analyses agreed that the albino capuchin monkey had color vision similar to that of non-albino dichromat monkeys, suggesting no influence of albinism on color discrimination.

A Note on the Voice Mismatch Asymmetry in Ellipsis.

Theories of ellipsis differ in the identity condition claimed to hold between an antecedent and an elided constituent. A syntactic identity condition leads to the prediction that syntactic mismatches between an antecedent and elided constituent should give rise to a penalty, and that penalty should be greater than in corresponding examples without ellipsis. Further, if syntactic mismatches are ungrammatical, violating the syntactic identity condition, then in effect they are speech errors and would be expected to be rated higher when a passive clause antecedes an active elided VP than vice versa because people misremember passives as actives more often the reverse. A written acceptability judgment study crossed the voice of the antecedent clause (active/passive), the voice of the ellipsis clause (active/passive) and ellipsis/non-ellipsis in the final clause. Results indicate a syntactic mismatch lowers acceptability in examples with elided VPs but not examples with overt VPs, as predicted by theories with a syntactic identity condition. Passive-active mismatches were rated better than active-passive ones, especially with ellipsis, as predicted by a speech error/repair approach to mismatches. This result eliminates any concern that the appearance of a voice asymmetry might only be due to some incompatibility between VP ellipsis and passive voice.

Ellipsis and Coreference Resolution in a Computerized Virtual Patient Dialogue System.

This paper describes the design of an ellipsis and coreference resolution module integrated in a computerized virtual patient dialogue system. Real medical diagnosis dialogues have been collected and analyzed. Several groups of diagnosis-related concepts were defined and used to construct rules, patterns, and features to detect and resolve ellipsis and coreference. The best F-scores of ellipsis detection and resolution were 89.15 % and 83.40 %, respectively. The best F-scores of phrasal coreference detection and resolution were 93.83 % and 83.40 %, respectively. The accuracy of pronominal anaphora resolution was 92 % for the 3rd-person singular pronouns referring to specific entities, and 97.31 % for other pronouns.

Identifying non-elliptical entity mentions in a coordinated NP with ellipses.

Named entities in the biomedical domain are often written using a Noun Phrase (NP) along with a coordinating conjunction such as 'and' and 'or'. In addition, repeated words among named entity mentions are frequently omitted. It is often difficult to identify named entities. Although various Named Entity Recognition (NER) methods have tried to solve this problem, these methods can only deal with relatively simple elliptical patterns in coordinated NPs. We propose a new NER method for identifying non-elliptical entity mentions with simple or complex ellipses using linguistic rules and an entity mention dictionary. The GENIA and CRAFT corpora were used to evaluate the performance of the proposed system. The GENIA corpus was used to evaluate the performance of the system according to the quality of the dictionary. The GENIA corpus comprises 3434 non-elliptical entity mentions in 1585 coordinated NPs with ellipses. The system achieves 92.11% precision, 95.20% recall, and 93.63% F-score in identification of non-elliptical entity mentions in coordinated NPs. The accuracy of the system in resolving simple and complex ellipses is 94.54% and 91.95%, respectively. The CRAFT corpus was used to evaluate the performance of the system under realistic conditions. The system achieved 78.47% precision, 67.10% recall, and 72.34% F-score in coordinated NPs. The performance evaluations of the system show that it efficiently solves the problem caused by ellipses, and improves NER performance. The algorithm is implemented in PHP and the code can be downloaded from https://code.google.com/p/medtextmining/.

Predicting contrast in sentences with and without focus marking.

How do we know when a contrast is coming? This study explores the prediction of parallel contrastive phrases, especially NPs, in sentences with and without overt focus marking. A written sentence-completion questionnaire with clauses followed by the conjunction "but" compared unmarked initial clauses to ones with the focus marker "only" on the subject or object. Both conditions with "only" elicited more contrasts overall than the condition without focus marking, and many of the contrasts were with the focus-marked NP. While the baseline (no-only) condition had full clauses for half of the completions, subject focus increased clausal completions and object focus increased negative ellipsis completions ("not"+NP structures), both changes in syntax which make a contrast with the marked NP easy. The production of negative ellipsis sentences primarily in the object-focus condition suggests that the object bias of these sentences in comprehension could relate to their being used more frequently with this meaning. Finally, the overall pattern of results shows that overt marking of contrastive focus increases continuations with contrasts, and the conjunction "but" does not reliably predict explicitly-stated contrasts within a sentence without overt focus marking.

Elliptical Responses to Direct and Indirect Requests for Information.

We present two studies examining the factors that lead speakers to produce elliptical responses to requests for information. Following Clark and Levelt and Kelter, experimenters called businesses and asked about their closing time (e.g., Can you tell me what time you close?). Participants provided the requested information in full sentence responses (We close at 9) or elliptical responses (At 9). A reanalysis of data from previous experiments using this paradigm shows that participants are more likely to produce an elliptical response when the question is a direct request for information (What time do you close?) than when the question is an indirect request for information (Can you tell me what time you close?). Participants were less likely to produce an elliptical response when they began their answer by providing a yes/no response (e.g., Sure . . . we close at 9). A new experiment replicated these findings, and further showed that elliptical responses were less likely when (1) irrelevant linguistic content was inserted between the question and the participant's response, and (2) participants verbalized signs of difficulty retrieving the requested information. This latter effect is most prominent in response to questions that are seen as very polite (May I ask you what time you close?). We discuss the role that the recoverability of the intended meaning of the ellipsis, the accessibility of potential antecedents for the ellipsis, pragmatic factors, and memory retrieval play in shaping the production of ellipsis.

Incremental structure building in the processing of ellipsis.

This article presents the results of two experiments conducted to examine how ellipsis sites are processed during the processing of backward sluicing, which is superficially similar to non-sluicing wh-filler-gap dependencies. Previous studies on long-distance wh-filler-gap dependencies established that the processing of these dependencies is sensitive to the syntactic structure of materials within the dependency: CP vs. NP. Results from two maze experiments show that backward sluicing processing is sensitive to the same structural factors, confirming that the same processing mechanism underlies both constructions. We suggest that an active search mechanism is operating at the core for these structures and with the interaction of the ellipsis-specific mechanism, e.g., a word-by-word copying mechanism, the parser builds antecedent structure within the ellipsis site incrementally during the processing of backward sluicing.

The role of L1 in L2 speech production at different stages of L2 development: Evidence from L2 Chinese oral production of verb-phrase ellipsis by English and Korean speakers.

The article reports on an empirical study investigating the role of L1 at the initial and developmental stages of L2 speech production. It examines two types of Chinese verb- phrase-ellipsis, ΣP-ellipsis licensed by the auxiliary shi 'BE' and vP-ellipsis licensed by the other auxiliaries, in 45 English and 45 Korean adult speakers' L2 Chinese speech production. An elicited imitation task was administered to L2 learners at beginner, intermediate and advanced Chinese proficiency levels. L1 influence is not observed at beginner levels, but it appears at intermediate and advanced levels, L1 influence disappears at different time in English and Korean learners' oral production of verb-ellipsis and ΣP-ellipsis. It is proposed that the absence of L1 influence at beginner levels is due to a breakdown of syntax-stylistics interface and beginners' difficulty in implementing checking and deleting operations in their L2 oral production. The different timings of the disappearance of L1 influence in the two language groups at advanced levels is attributed to interactions between the persistence of L1 influence and the computational complexity involved in the target elliptical structures.

The Role of UID for the Usage of Verb Phrase Ellipsis: Psycholinguistic Evidence From Length and Context Effects.

We investigate the underexplored question of when speakers make use of the omission phenomenon verb phrase ellipsis (VPE) in English given that the full form is also available to them. We base the interpretation of our results on the well-established information-theoretic Uniform Information Density (UID) hypothesis: Speakers tend to distribute processing effort uniformly across utterances and avoid regions of low information by omitting redundant material through, e.g., VPE. We investigate the length of the omittable VP and its predictability in context as sources of redundancy which lead to larger or deeper regions of low information and an increased pressure to use ellipsis. We use both naturalness rating and self-paced reading studies in order to link naturalness patterns to potential processing difficulties. For the length effects our rating and reading results support a UID account. Surprisingly, we do not find an effect of the context on the naturalness and the processing of VPE. We suggest that our manipulation might have been too weak or not effective to evidence such an effect.

Predictable Words Are More Likely to Be Omitted in Fragments-Evidence From Production Data.

Instead of a full sentence like Bring me to the university (uttered by the passenger to a taxi driver) speakers often use fragments like To the university to get their message across. So far there is no comprehensive and empirically supported account of why and under which circumstances speakers sometimes prefer a fragment over the corresponding full sentence. We propose an information-theoretic account to model this choice: A speaker chooses the encoding that distributes information most uniformly across the utterance in order to make the most efficient use of the hearer's processing resources (Uniform Information Density, Levy and Jaeger, 2007). Since processing effort is related to the predictability of words (Hale, 2001) our account predicts two effects of word probability on omissions: First, omitting predictable words (which are more easily processed), avoids underutilizing processing resources. Second, inserting words before very unpredictable words distributes otherwise excessively high processing effort more uniformly. We test these predictions with a production study that supports both of these predictions. Our study makes two main contributions: First we develop an empirically motivated and supported account of fragment usage. Second, we extend previous evidence for information-theoretic processing constraints on language in two ways: We find predictability effects on omissions driven by extralinguistic context, whereas previous research mostly focused on effects of local linguistic context. Furthermore, we show that omissions of content words are also subject to information-theoretic well-formedness considerations. Previously, this has been shown mostly for the omission of function words.

"The tiger is hitting! the duck too!" 3-year-olds can use prosodic information to constrain their interpretation of ellipsis.

This work aims to investigate French children's ability to use phrasal boundaries for disambiguation of a type of ambiguity not yet studied, namely stripping sentences versus simple transitive sentences. We used stripping sentences such as "[Le tigre tape]! [Le canard aussi]!" ("[The tiger is hitting]! [The duck too]!", in which both the tiger and the duck are hitting), which, without the prosodic information, would be ambiguous with a transitive sentence such as "[Le tigre] [tape le canard aussi]!" ("[The tiger] [is hitting the duck too]!", in which the tiger is hitting the duck). We presented 3-to-4-year-olds and 28-month-olds with one of the two types of sentence above, while they watched two videos side-by-side on a screen: one depicting the transitive interpretation of the sentences, and another depicting the stripping interpretation. The stripping interpretation video showed the two characters as agents of the named action (e.g. a duck and a tiger hitting a bunny), and the transitive interpretation video showed only the first character as an agent, and the second character as a patient of the action (e.g. the tiger hitting the duck and the bunny). The results showed that 3-to-4-year-olds use prosodic information to correctly distinguish stripping sentences from transitive sentences, as they looked significantly more at the appropriate video, while 28-month-olds show only a trend in the same direction. While recent studies demonstrated that from 18 months of age, infants are able to use phrasal prosody to guide the syntactic analysis of ambiguous sentences, our results show that only 3-to-4-year-olds were able to reliably use phrasal prosody to constrain the parsing of stripping sentences. We discuss several factors that can explain this delay, such as differences in the frequency of these structures in child-directed speech, as well as in the complexity of the sentences and of the experimental task. Our findings add to the growing body of evidence on the role of prosody in constraining parsing in young children.

Reduced NP comparatives in Korean and their implications.

In this paper, I examine a novel type of comparative construction in Korean, namely, reduced NP comparatives (RNC), and consider its implications. On the surface, RNC may appear to be a case of the usual NP comparative construction in that two NPs are involved. But, unlike typical NP comparatives, the element bearing the marker of the standard of comparison in RNC does not directly participate in the comparison, i.e., there is a mismatch between the standard and pivot. I argue this is due to the fact that the standard is reduced to leave only the pivot on the surface, hence the name "reduced" NP comparatives. I also argue that one of the factors that determines the availability of RNC is the notion of comparability, which is based on whether or not the compared elements can be associated with the same scale, where the scale is part of the semantics of the gradable predicate (Cf. Kennedy 2009). The interesting twist is that RNC is possible only if the relevant elements are not comparable with each other, i.e., they should denote different types of objects that cannot be associated with the same scale. Adopting Merchant's (The syntax of silence: sluicing, islands, and the theory of ellipsis. Oxford University Press, Oxford, 2001, Linguist Philos 27:661-738, 2004, J Greek Linguist 9:134-164, 2009, among others) move-and-delete approach to various ellipsis constructions, I propose a move-and-delete analysis of RNC, where the pivot undergoes movement, followed by deletion of the rest of the standard. The discussion also has implications for NP-ellipsis in Korean.

A graph-based method for reconstructing entities from coordination ellipsis in medical text.

OBJECTIVE: Coordination ellipsis is a linguistic phenomenon abound in medical text and is challenging for concept normalization because of difficulty in recognizing elliptical expressions referencing 2 or more entities accurately. To resolve this bottleneck, we aim to contribute a generalizable method to reconstruct concepts from medical coordinated elliptical expressions in a variety of biomedical corpora. MATERIALS AND METHODS: We proposed a graph-based representation model and built a pipeline to reconstruct concepts from coordinated elliptical expressions in medical text (RECEEM). There are 4 modules: (1) identify all possible candidate conjunct pairs from original coordinated elliptical expressions, (2) calculate coefficients for candidate conjuncts using the embedding model, (3) select the most appropriate decompositions by global optimization, and (4) rebuild concepts based on a pathfinding algorithm. We evaluated the pipeline's performance on 2658 coordinated elliptical expressions from 3 different medical corpora (ie, biomedical literature, clinical narratives, and eligibility criteria from clinical trials). Precision, recall, and F1 score were calculated. RESULTS: The F1 scores for biomedical publications, clinical narratives, and research eligibility criteria were 0.862, 0.721, and 0.870, respectively. RECEEM outperformed 2 previously released methods. By incorporating RECEEM into 2 existing NLP tools, the F1 scores increased from 0.248 to 0.460 and from 0.287 to 0.630 on concept mapping of 1125 coordination ellipses. CONCLUSIONS: RECEEM improves concept normalization for medical coordinated elliptical expressions in a variety of biomedical corpora. It outperformed existing methods and significantly enhanced the performance of 2 notable NLP systems for mapping coordination ellipses in the evaluation. The algorithm is open sourced online (https://github.com/chiyuan1126/RECEEM).

Processing gapping: Parallelism and grammatical constraints.

This study aims to test two hypotheses about the online processing of Gapping: whether the parser inserts an ellipsis site in an incremental fashion in certain coordinated structures (the Incremental Ellipsis Hypothesis), or whether ellipsis is a late and dispreferred option (the Ellipsis as a Last Resort Hypothesis). We employ two offline acceptability rating experiments and a sentence fragment completion experiment to investigate to what extent the distribution of Gapping is controlled by grammatical and extra-grammatical constraints. Furthermore, an eye-tracking while reading experiment demonstrated that the parser inserts an ellipsis site incrementally but only when grammatical and extra-grammatical constraints allow for the insertion of the ellipsis site. This study shows that incremental building of the Gapping structure follows from the parser's general preference to keep the structure of the two conjuncts maximally parallel in a coordination structure as well as from grammatical restrictions on the distribution of Gapping such as the Coordination Constraint.

Clinical hemodialysis experience with percutaneous arteriovenous fistulas created using the Ellipsys® vascular access system.

INTRODUCTION: The aim of this study is to report our clinical hemodialysis experience using a percutaneous arteriovenous fistula (pAVF) created with the Ellipsys® vascular access system. This pAVF device creates a permanent AVF anastomosis between the proximal radial artery (PRA) and the deep communicating vein (DCV) in the proximal forearm. METHODS: The medical records of all patients with a pAVF were retrospectively reviewed. The clinical data analyzed included reliability of pAVF use, quality of dialysis, rate and success of puncture, and pAVF related complications, along with incidence of subsequent interventions. FINDINGS: Between May 2017 and November 2018, 34 patients had a pAVF created with technical success in 33 patients (97%). Twenty-eight out of 34 (82%) patients had successful two-needle cannulation within 10 days to 6 weeks after pAVF creation. The mean Kt/v was 1.6 (1.2-2) and the average recirculation was 10%. Fifteen patients (44%) needed no further access intervention. Twelve patients (35%) required an additional procedure to assist maturation of the pAVF in order to facilitate puncture. The average blood flow measured at the brachial artery, before the first cannulation, was 850 ml/min. From causes unrelated to the procedure, four patients died during the follow-up study. Two patients required revision to a surgical AVF. None of the pAVFs developed aneurysmal degeneration steal syndrome, or high access flow related issues. DISCUSSION: The Ellipsys® pAVF offers a safe and functional vascular access for hemodialysis. Advantages included prompt access maturation, avoidance of high flow AVFs, and a simple nonsurgical procedure with high patient satisfaction. Functional outcomes are equivalent and likely better than surgical fistulas. There appears to be less aneurysmal degeneration and need for future re-intervention. Objective dialysis parameters indicate excellent quality of hemodialysis for the patient.

Correlate not optional: PP sprouting and parallelism in "much less" ellipsis.

Clauses that are parallel in form and meaning show processing advantages in ellipsis and coordination structures (Frazier et al. 1984; Kehler 2000; Carlson 2002). However, the constructions that have been used to show a parallelism advantage do not always require a strong semantic relationship between clauses. We present two eye tracking while reading studies on focus-sensitive coordination structures, an understudied form of ellipsis which requires the generation of a contextually salient semantic relation or scale between conjuncts. However, when the remnant of ellipsis lacks an overt correlate in the matrix clause and must be "sprouted" in the ellipsis site, the relation between clauses is simplified to entailment. Instead of facilitation for sentences with an entailment relation between clauses, our online processing results suggest that violating Parallelism is costly, even when doing so could ease the semantic relations required for interpretation.

Zero-Adjective Contrast in Much-less Ellipsis: The Advantage for Parallel Syntax.

This paper explores the processing of sentences with a much less coordinator (I don't own a pink hat, much less a red one). This understudied ellipsis sentence, one of several focus-sensitive coordination structures, imposes syntactic and semantic conditions on the relationship between the correlate (a pink hat) and remnant (a red one). We present the case of zero-adjective contrast, in which an NP remnant introduces an adjective without an overt counterpart in the correlate (I don't own a hat, much less a red one). Although zero-adjective contrast could in principle ease comprehension by limiting the possible relationships between the remnant and correlate to entailment, we find that zero-adjective contrast is avoided in production and taxing in online processing. Results from several studies support a processing model in which syntactic parallelism is the primary guide for determining contrast in ellipsis structures, even when violating parallelism would assist in computing semantic relationships.

Information Structure Preferences in Focus-Sensitive Ellipsis: How Defaults Persist.

We compare the roles of overt accent and default focus marking in processing ellipsis structures headed by focus-sensitive coordinators (such as Danielle couldn't pass the quiz, let alone the final/Kayla). In a small auditory corpus study of radio transcripts, we establish that such structures overwhelmingly occur with contrastive pitch accents on the correlate and remnant ( the quiz and the final, or Danielle and Kayla), and that there is a strong bias to pair the remnant with the most local plausible correlate in production. In two auditory naturalness ratings experiments, we observe that marking a non-local correlate with contrastive pitch accent moderates, but does not fully overturn, the bias for local correlates in comprehension. We propose that the locality preference is due to a sentence-final default position for sentence accent, and that auditory processing is subject to "enduring focus," in which default positions for focus continue to influence the focus structure of the sentence even in the presence of overt accents. The importance of these results for models of auditory processing and of the processing of remnants in ellipsis structures is discussed.

Keep it local (and final): Remnant preferences in "let alone" ellipsis.

The let alone construction (John can't run a mile, let alone a marathon) differs from standard coordination structures (with and or but) by requiring ellipsis of the second conjunct--for example, a marathon is the remnant of an elided clause [[see text] a marathon]. In support of an ellipsis account, a corpus study of British and American English finds that let alone exhibits a Locality bias, as the second conjunct preferentially contrasts with the nearest lexical item of the same syntactic type. Two self-paced reading studies show that the Locality bias is active during online processing, but must be reconciled with indicators of semantic contrast and discourse information. Further, a sentence-rating study shows that the Locality bias interacts with a Finality bias that favours placing the let alone phrase at the end of a clause, which sometimes necessitates a nonlocal contrast. Together, the results show how a general bias in ellipsis for local contrasts is affected by discourse demands, such as the need for scalar contrast imposed by let alone, thereby offering a window into how possibly divergent syntactic and discourse constraints impact sentence processing.

Filling the Silence: Reactivation, not Reconstruction.

In a self-paced reading experiment, we investigated the processing of sluicing constructions ("sluices") whose antecedent contained a known garden-path structure in German. Results showed decreased processing times for sluices with garden-path antecedents as well as a disadvantage for antecedents with non-canonical word order downstream from the ellipsis site. A post-hoc analysis showed the garden-path advantage also to be present in the region right before the ellipsis site. While no existing account of ellipsis processing explicitly predicted the results, we argue that they are best captured by combining a local antecedent mismatch effect with memory trace reactivation through reanalysis.