145 research outputs found

    The past tense inflection project (PTIP): speeded past tense inflections, imageability ratings, and past tense consistency measures for 2,200 verbs

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    Abstract The processes involved in past tense verb generation have been central to models of inflectional morphology. However, the empirical support for such models has often been based on studies of accuracy in past tense verb formation on a relatively small set of items. We present the first largescale study of past tense inflection (the Past Tense Inflection Project, or PTIP) that affords response time, accuracy, and error analyses in the generation of the past tense form from the present tense form for over 2,000 verbs. In addition to standard lexical variables (such as word frequency, length, and orthographic and phonological neighborhood), we have also developed new measures of past tense neighborhood consistency and verb imageability for these stimuli, and via regression analyses we demonstrate the utility of these new measures in predicting past tense verb generation. The PTIP can be used to further evaluate existing models, to provide well controlled stimuli for new studies, and to uncover novel theoretical principles in past tense morphology. Keywords Verb processing . Megastudy . Past tense inflection . Item-level variance . Verb consistency . Verb imageability A long-standing question in language acquisition and inflectional morphology is how individuals produce the past tense form of a verb. Past tense inflection (PTI), like spelling-to-sound conversion in English, is quasiregular, meaning that a set of generally applicable descriptive rules are useful for most verbs (e.g., add -ed to the stem form), but there are also some irregular forms (e.g., dodid) and subregularities (as in the eep-ept past tense family: sleep-slept, weep-wept, keep-kept, etc.). Indeed, past tense inflection has been a central focus of the debate between parallel distributed models Although there has been extensive theoretical work in the area of past tense verb generation, experimental work examining response times (RTs) has been relatively limited. For example, in the stem inflection task, participants are asked to produce the past tense (real or hypothetical) of a target verb or novel nonword (e.g., Only a few previous studies of past tense verb inflection have used RT as a dependent variable: Joanisse and Seidenberg One way to address the discrepancies among previous studies, as well as the limitations associated with factorial designs employing relatively few stimuli, is to sample a much larger set of items from the language. Megastudies include stimuli on the order of thousands, rather than 50 to 100, and allow for the effects of variables to be modeled continuously rather than categorically (see In addition to providing a large database of response latencies and accuracies for past tense verb inflection, we also developed two new measures that are important to consider in past tense inflection, consistency and imageability. Similar to the spelling-to-sound consistency measure that has been well-studied in visual word recognition research The second variable that we measured was imageability. Imageability is a variable that reflects the extent to which 152 Behav Res (2013) 45:151-159 one is able to form a mental image of a word, and indeed many imageability norms are already available (e.g., The present study is based on 89 participants' accuracy and RTs for a past tense inflection task with 2,200 verbs. Each participant produced responses to 888 items. For each verb in the PTIP database, we included measures of RT, accuracy, and regularization errors (e.g., saying GRINDED for GRIND), along with the new imageability and consistency measures described above. The PTIP database is useful in examining the specific effects of predictor variables on RT and accuracy and allows for detailed item-level predictions. It is available as supplementary materials with this article for researchers who plan to examine other theoretical questions about past tense inflection, or are hoping to select well-controlled and well-examined stimuli for new studies. These data will serve as both a reference and an impetus for further research in the domain of past tense inflection. Experiment 1 The first experiment was conducted in order to collect imageability rating norms for the verbs in the PTIP database. Method Participants A group of 218 participants were recruited via Amazon's Mechanical Turk (AMT; see Materials The 2,200 words from the PTIP database (see below), plus another 112 words for use in another study, were divided into eight lists of 289 items each. The eight lists were presented as separate jobs in AMT. Procedure Each participant completed one list of the rating task, which was presented in Adobe Flash and appeared after a consent screen in the AMT job description. The instructions were the same as those used in Results The ratings were aggregated across participants for each item (excluding "do not know" responses), so that one mean imageability value was calculated for each verb. These values were used in Experiment 2 (see below). The mean rating across all verbs was 4.28 (SD 0 0.92), and the mean RT across all verbs was 3,191 ms (SD 0 1,695). The overall split-half reliability was r 0 .80, p < .001. Experiment 2 Method Participants A group of 113 native English-speaking college students from the Washington University subject pool participated in Behav Res (2013) 45:151-159 153 the study. After eliminating extreme outliers (less than 80 % accuracy overall; four participants) or participants whose data were subject to recording error (missing sound files from which to code accuracy-20 participants), 89 participants contributed to the final database

    The first consensus statement on revisional bariatric surgery using a modified Delphi approach

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    Background: Revisional bariatric surgery (RBS) constitutes a possible solution for patients who experience an inadequate response following bariatric surgery or significant weight regain following an initial satisfactory response. This paper reports results from the first modified Delphi consensus-building exercise on RBS. Methods: We created a committee of 22 recognised opinion-makers with a special interest in RBS. The committee invited 70 RBS experts from 27 countries to vote on 39 statements concerning RBS. An agreement amongst ≄ 70.0% experts was regarded as a consensus. Results: Seventy experts from twenty-seven countries took part. There was a consensus that the decision for RBS should be individualised (100.0%) and multi-disciplinary (92.8%). Experts recommended a preoperative nutritional (95.7%) and psychological evaluation (85.7%), endoscopy (97.1%), and a contrast series (94.3%). Experts agreed that Roux-Y gastric bypass (RYGB) (94.3%), One anastomosis gastric bypass (OAGB) (82.8%), and single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) (71.4%) were acceptable RBS options after gastric banding (84.3%). OAGB (84.3%), bilio-pancreatic diversion/duodenal switch (BPD/DS) (81.4%), and SADI-S (88.5%) were agreed as consensus RBS options after sleeve gastrectomy. lengthening of bilio-pancreatic limb was the only consensus RBS option after RYGB (94.3%) and OAGB (72.8%). Conclusion: Experts achieved consensus on a number of aspects of RBS. Though expert opinion can only be regarded as low-quality evidence, the findings of this exercise should help improve the outcomes of RBS while we develop robust evidence to inform future practice

    Physics and Applications of Laser Diode Chaos

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    An overview of chaos in laser diodes is provided which surveys experimental achievements in the area and explains the theory behind the phenomenon. The fundamental physics underpinning this behaviour and also the opportunities for harnessing laser diode chaos for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient test-bed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.Comment: Published in Nature Photonic

    Perioperative outcome of laparoscopic left lateral liver resection is improved by using a bioabsorbable staple line reinforcement material in a porcine model

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    Hypothesis Laparoscopic liver surgery is significantly limited by the technical difficulty encountered during transection of substantial liver parenchyma, with intraoperative bleeding and bile leaks. This study tested whether the use of a bioabsorble staple line reinforcement material would improve outcome during stapled laparoscopic left lateral liver resection in a porcine model. Study design A total of 20 female pigs underwent stapled laparoscopic left lateral liver resection. In group A (n = 10), the stapling devices were buttressed with a bioabsorbable staple line reinforcement material. In group B (n = 10), standard laparoscopic staplers were used. Operative data and perioperative complications were recorded. Necropsy studies and histopathological analysis were performed at 6 weeks. Data were compared between groups with the Student's t-test or the chi-square test. Results Operating time was similar in the two groups (64 +/- 11 min in group A versus 68 +/- 9 min in group B, p = ns). Intraoperative blood loss was significantly higher in group B (185 +/- 9 mL versus 25 +/- 5 mL, p <0.05). There was no mortality. There was no morbidity in the 6-week follow-up period; however, two animals in group B had subphrenic bilomas (20%) at necropsy. At necropsy, methylene blue injection via the main bile duct revealed leakage from the biliary tree in four animals in group B and none in group A (p <0.05). Histopathological examination of the resection site revealed minor abnormalities in group A while animals in group B demonstrated marked fibrotic changes and damaged vascular and biliary endothelium. Conclusion Use of a bioabsorbable staple line reinforcement material reduces intraoperative bleeding and perioperative bile leaks during stapled laparoscopic left lateral liver resection in a porcine model

    Metabolic and Bariatric Surgery in Patients with Obesity Class V (BMI > 60 kg/m2): a Modified Delphi Study

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    Background: Metabolic and bariatric surgery (MBS) is the preferred method to achieve significant weight loss in patients with Obesity Class V (BMI > 60 kg/m2). However, there is no consensus regarding the best procedure(s) for this population. Additionally, these patients will likely have a higher risk of complications and mortality. The aim of this study was to achieve a consensus among a global panel of expert bariatric surgeons using a modified Delphi methodology. Methods: A total of 36 recognized opinion-makers and highly experienced metabolic and bariatric surgeons participated in the present Delphi consensus. 81 statements on preoperative management, selection of the procedure, perioperative management, weight loss parameters, follow-up, and metabolic outcomes were voted on in two rounds. A consensus was considered reached when an agreement of ≄ 70% of experts' votes was achieved. Results: A total of 54 out of 81 statements reached consensus. Remarkably, more than 90% of the experts agreed that patients should be notified of the greater risk of complications, the possibility of modifications to the surgical procedure, and the early start of chemical thromboprophylaxis. Regarding the choice of the procedure, SADI-S, RYGB, and OAGB were the top 3 preferred operations. However, no consensus was reached on the limb length in these operations. Conclusion: This study represents the first attempt to reach consensus on the choice of procedures as well as perioperative management in patients with obesity class V. Although overall consensus was reached in different areas, more research is needed to better serve this high-risk population.info:eu-repo/semantics/publishedVersio

    Adjustable Intragastric Balloons: A 12-Month Pilot Trial in Endoscopic Weight Loss Management

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    Intragastric balloons are associated with (1) early period intolerance, (2) diminished effect within 3–4 months, and (3) bowel obstruction risk mandating removal at 6 months. The introduction of an adjustable balloon could improve comfort and offer greater efficacy. A migration prevention function, safely enabling prolonged implantation, could improve efficacy and weight maintenance post-extraction. The first implantations of an adjustable balloon with an attached migration prevention anchor are reported. The primary endpoint was the absence of bowel perforation, obstruction, or hemorrhage. Eighteen patients with mean BMI of 37.3 were implanted with the Spatz Adjustable Balloon system (ABS) for 12 months. Balloon volumes were adjusted for intolerance or weight loss plateau. Mean weight loss at 24 weeks was 15.6 kg with 26.4% EWL (percent of excess weight loss) and 24.4 kg with 48.8% EWL at 52 weeks. Sixteen adjustments were successfully performed. Six downward adjustments alleviated intolerance, yielding additional mean weight loss of 4.6 kg. Ten upward adjustments for weight loss plateau yielded a mean additional weight loss of 7 kg. Seven balloons were removed prematurely. Complications necessitating early removal included valve malfunction (1), gastritis (1), Mallory–Weiss tear (1), NSAID (2× dose/2 weeks) perforating ulcer (1), and balloon deflation (1). Two incidents of catheter shear from the chain: one passed uneventfully and one caused an esophageal laceration without perforation during extraction. The Spatz ABS has been successfully implanted in 18 patients. (1) Upward adjustments yielded additional weight loss. (2) Downward adjustments alleviated intolerance, with continued weight loss. (3) Preliminary 1-year implantation results are encouraging

    Prevalence, symptoms and management of uterine fibroids: an international internet-based survey of 21,746 women

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    <p>Abstract</p> <p>Background</p> <p>In 2009 the Uterine Bleeding and Pain Women's Research Study (UBP-WRS) was conducted interviewing 21,479 women across 8 countries in order to gain patient-based prevalence data on uterine pain and bleeding indications and investigate uterine symptoms and women's treatment experiences. This article shows relevant results of the study for the indication uterine fibroids providing data on self-reported prevalence, symptomatology and management of uterine fibroids.</p> <p>Methods</p> <p>2,500 women (USA: 4,500 women) in each country (Brazil, Canada, France, Germany, Italy, South Korea, the UK, the USA) completed an online survey. Women included were in their reproductive age (age group 15-49 years; USA: 18-49 years) and had ever experienced menstrual bleedings. Quotas were applied for age, region, level of education and household income of respondents. Variables have been analyzed descriptively and exploratory statistical tests have been performed.</p> <p>Results</p> <p>The self-reported prevalence of uterine fibroids ranged from 4.5% (UK) to 9.8% (Italy), reaching 9.4% (UK) to 17.8% (Italy) in the age group of 40-49 years. Women with a diagnosis of uterine fibroids reported significantly more often about bleeding symptoms than women without a diagnosis: heavy bleedings (59.8% vs. 37.4%), prolonged bleedings (37.3% vs. 15.6%), bleeding between periods (33.3% vs. 13.5%), frequent periods (28.4% vs. 15.2%), irregular and predictable periods (36.3% vs. 23.9%). Furthermore women with diagnosed uterine fibroids reported significantly more often about the following pain symptoms: pressure on the bladder (32.6% vs. 15.0%), chronic pelvic pain (14.5% vs. 2.9%), painful sexual intercourse (23.5% vs. 9.1%) and pain occurring mid-cycle, after and during menstrual bleeding (31.3%, 16.7%, 59.7%, vs. 17.1%, 6.4%, 52.0%). 53.7% of women reported that their symptoms had a negative impact on their life in the last 12 month, influencing their sexual life (42.9%), performance at work (27.7%) and relationship & family (27.2%).</p> <p>Conclusions</p> <p>Uterine fibroid is a common concern in women at fertile age causing multiple bleeding and pain symptoms which can have a negative impact on different aspects in women's life.</p

    IFSO (International Federation for Surgery of Obesity and Metabolic Disorders) Consensus Conference Statement on One-Anastomosis Gastric Bypass (OAGB-MGB): Results of a Modified Delphi Study

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    Background: One-anastomosis gastric bypass (OAGB-MGB) is currently the third performed primary bariatric surgical procedure worldwide. However, the procedure is hampered by numerous controversies and there is considerable variability in surgical technique, patient selection, and pre- and postoperative care among the surgeons performing this procedure. This paper reports the results of a modified Delphi consensus study organized by the International Federation for Surgery of Obesity and Metabolic Disorders (IFSO). Methods: Fifty-two internationally recognized bariatric experts from 28 countries convened for voting on 90 consensus statements over two rounds to identify those on which consensus could be reached. Inter-voter agreement of ≄ 70% was considered consensus, with voting participation ≄ 80% considered a robust vote. Results: At least 70% consensus was achieved for 65 of the 90 questions (72.2% of the items), 61 during the first round of voting and an additional four in the second round. Where consensus was reached on a binary agree/disagree or yes/no item, there was agreement with the statement presented in 53 of 56 instances (94.6%). Where consensus was reached on a statement where options favorable versus unfavorable to OAGB-MGB were provided, including statements in which OAGB-MGB was compared to another procedure, the response option favorable to OAGB-MGB was selected in 13 of 23 instances (56.5%). Conclusion: Although there is general agreement that the OAGB-MGB is an effective and usually safe option for the management of patients with obesity or severe obesity, numerous areas of non-consensus remain in its use. Further empirical data are needed
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