Deep neural networks (DNNs) have been playing a significant role in acoustic modeling. Convolutional neural networks (CNNs) are the advanced version of DNNs that achieve 4–12% relative gain in the ...word error rate (WER) over DNNs. Existence of spectral variations and local correlations in speech signal makes CNNs more capable of speech recognition. Recently, it has been demonstrated that bidirectional long short-term memory (BLSTM) produces higher recognition rate in acoustic modeling because they are adequate to reinforce higher-level representations of acoustic data. Spatial and temporal properties of the speech signal are essential for high recognition rate, so the concept of combining two different networks came into mind. In this paper, a hybrid architecture of CNN-BLSTM is proposed to appropriately use these properties and to improve the continuous speech recognition task. Further, we explore different methods like weight sharing, the appropriate number of hidden units, and ideal pooling strategy for CNN to achieve a high recognition rate. Specifically, the focus is also on how many BLSTM layers are effective. This paper also attempts to overcome another shortcoming of CNN, i.e. speaker-adapted features, which are not possible to be directly modeled in CNN. Next, various non-linearities with or without dropout are analyzed for speech tasks. Experiments indicate that proposed hybrid architecture with speaker-adapted features and maxout non-linearity with dropout idea shows 5.8% and 10% relative decrease in WER over the CNN and DNN systems, respectively.
Background
Standard surgical training has traditionally been one of apprenticeship, where the surgical trainee learns to perform surgery under the supervision of a trained surgeon. This is ...time‐consuming, costly, and of variable effectiveness. Training using a virtual reality simulator is an option to supplement standard training. Virtual reality training improves the technical skills of surgical trainees such as decreased time for suturing and improved accuracy. The clinical impact of virtual reality training is not known.
Objectives
To assess the benefits (increased surgical proficiency and improved patient outcomes) and harms (potentially worse patient outcomes) of supplementary virtual reality training of surgical trainees with limited laparoscopic experience.
Search methods
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE and Science Citation Index Expanded until July 2012.
Selection criteria
We included all randomised clinical trials comparing virtual reality training versus other forms of training including box‐trainer training, no training, or standard laparoscopic training in surgical trainees with little laparoscopic experience. We also planned to include trials comparing different methods of virtual reality training. We included only trials that assessed the outcomes in people undergoing laparoscopic surgery.
Data collection and analysis
Two authors independently identified trials and collected data. We analysed the data with both the fixed‐effect and the random‐effects models using Review Manager 5 analysis. For each outcome we calculated the mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals based on intention‐to‐treat analysis.
Main results
We included eight trials covering 109 surgical trainees with limited laparoscopic experience. Of the eight trials, six compared virtual reality versus no supplementary training. One trial compared virtual reality training versus box‐trainer training and versus no supplementary training, and one trial compared virtual reality training versus box‐trainer training. There were no trials that compared different forms of virtual reality training. All the trials were at high risk of bias. Operating time and operative performance were the only outcomes reported in the trials. The remaining outcomes such as mortality, morbidity, quality of life (the primary outcomes of this review) and hospital stay (a secondary outcome) were not reported.
Virtual reality training versus no supplementary training: The operating time was significantly shorter in the virtual reality group than in the no supplementary training group (3 trials; 49 participants; MD ‐11.76 minutes; 95% CI ‐15.23 to ‐8.30). Two trials that could not be included in the meta‐analysis also showed a reduction in operating time (statistically significant in one trial). The numerical values for operating time were not reported in these two trials. The operative performance was significantly better in the virtual reality group than the no supplementary training group using the fixed‐effect model (2 trials; 33 participants; SMD 1.65; 95% CI 0.72 to 2.58). The results became non‐significant when the random‐effects model was used (2 trials; 33 participants; SMD 2.14; 95% CI ‐1.29 to 5.57). One trial could not be included in the meta‐analysis as it did not report the numerical values. The authors stated that the operative performance of virtual reality group was significantly better than the control group.
Virtual reality training versus box‐trainer training: The only trial that reported operating time did not report the numerical values. In this trial, the operating time in the virtual reality group was significantly shorter than in the box‐trainer group. Of the two trials that reported operative performance, only one trial reported the numerical values. The operative performance was significantly better in the virtual reality group than in the box‐trainer group (1 trial; 19 participants; SMD 1.46; 95% CI 0.42 to 2.50). In the other trial that did not report the numerical values, the authors stated that the operative performance in the virtual reality group was significantly better than the box‐trainer group.
Authors' conclusions
Virtual reality training appears to decrease the operating time and improve the operative performance of surgical trainees with limited laparoscopic experience when compared with no training or with box‐trainer training. However, the impact of this decreased operating time and improvement in operative performance on patients and healthcare funders in terms of improved outcomes or decreased costs is not known. Further well‐designed trials at low risk of bias and random errors are necessary. Such trials should assess the impact of virtual reality training on clinical outcomes.
Background Failures in nontechnical and teamwork skills frequently lie at the heart of harm and near-misses in the operating room (OR). The purpose of this systematic review was to assess the impact ...of nontechnical skills on technical performance in surgery. Study Design MEDLINE, EMBASE, PsycINFO databases were searched, and 2,041 articles were identified. After limits were applied, 341 articles were retrieved for evaluation. Of these, 28 articles were accepted for this review. Data were extracted from the articles regarding sample population, study design and setting, measures of nontechnical skills and technical performance, study findings, and limitations. Results Of the 28 articles that met inclusion criteria, 21 articles assessed the impact of surgeons' nontechnical skills on their technical performance. The evidence suggests that receiving feedback and effectively coping with stressful events in the OR has a beneficial impact on certain aspects of technical performance. Conversely, increased levels of fatigue are associated with detriments to surgical skill. One article assessed the impact of anesthesiologists' nontechnical skills on anesthetic technical performance, finding a strong positive correlation between the 2 skill sets. Finally, 6 articles assessed the impact of multiple nontechnical skills of the entire OR team on surgical performance. A strong relationship between teamwork failure and technical error was empirically demonstrated in these studies. Conclusions Evidence suggests that certain nontechnical aspects of performance can enhance or, if lacking, contribute to deterioration of surgeons' technical performance. The precise extent of this effect remains to be elucidated.
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GEOZS, NUK, OILJ, SBJE, UL, UPUK
This paper provides the first systematic analysis of performance patterns for emerging funds and managers in the hedge fund industry. Emerging funds and managers have particularly strong financial ...incentives to create investment performance and, because of their size, may be more nimble than established ones. Performance measurement, however, needs to control for the usual biases afflicting hedge fund databases. After adjusting for such biases and using a novel event time approach, we find strong evidence of outperformance during the first two to three years of existence. Each additional year of age decreases performance by 42 basis points, on average. Cross-sectionally, early performance by individual funds is quite persistent, with early strong performance lasting for up to five years.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
OBJECTIVE:This study evaluates whether video-based coaching can enhance laparoscopic surgical skills performance.
BACKGROUND:Many professions utilize coaching to improve performance. The sports ...industry employs video analysis to maximize improvement from every performance.
METHODS:Laparoscopic novices were baseline tested and then trained on a validated virtual reality (VR) laparoscopic cholecystectomy (LC) curriculum. After competence, subjects were randomized on a 1:1 ratio and each performed 5 VRLCs. After each LC, intervention group subjects received video-based coaching by a surgeon, utilizing an adaptation of the GROW (Goals, Reality, Options, Wrap-up) coaching model. Control subjects viewed online surgical lectures. All subjects then performed 2 porcine LCs. Performance was assessed by blinded video review using validated global rating scales.
RESULTS:Twenty subjects were recruited. No significant differences were observed between groups in baseline performance and in VRLC1. For each subsequent repetition, intervention subjects significantly outperformed controls on all global rating scales. Interventions outperformed controls in porcine LC1 Global Operative Assessment of Laparoscopic Skills(20.5 vs 15.5; P = 0.011), Objective Structured Assessment of Technical Skills(21.5vs 14.5; P = 0.001), and Operative Performance Rating System(26 vs 19.5; P = 0.001) and porcine LC2 Global Operative Assessment of Laparoscopic Skills(28 vs 17.5; P = 0.005), Objective Structured Assessment of Technical Skills(30 vs 16.5; P < 0.001), and Operative Performance Rating System(36 vs 21; P = 0.004). Intervention subjects took significantly longer than controls in porcine LC1 (2920 vs 2004 seconds; P = 0.009) and LC2 (2297 vs 1683; P = 0.003).
CONCLUSIONS:Despite equivalent exposure to practical laparoscopic skills training, video-based coaching enhanced the quality of laparoscopic surgical performance on both VR and porcine LCs, although at the expense of increased time. Video-based coaching is a feasible method of maximizing performance enhancement from every clinical exposure.
Abstract Background Validated methods of objective assessments of surgical skills are resource intensive. We sought to test a web-based grading tool using crowdsourcing called Crowd-Sourced ...Assessment of Technical Skill. Materials and methods Institutional Review Board approval was granted to test the accuracy of Amazon.com's Mechanical Turk and Facebook crowdworkers compared with experienced surgical faculty grading a recorded dry-laboratory robotic surgical suturing performance using three performance domains from a validated assessment tool. Assessor free-text comments describing their rating rationale were used to explore a relationship between the language used by the crowd and grading accuracy. Results Of a total possible global performance score of 3–15, 10 experienced surgeons graded the suturing video at a mean score of 12.11 (95% confidence interval CI, 11.11–13.11). Mechanical Turk and Facebook graders rated the video at mean scores of 12.21 (95% CI, 11.98–12.43) and 12.06 (95% CI, 11.57–12.55), respectively. It took 24 h to obtain responses from 501 Mechanical Turk subjects, whereas it took 24 d for 10 faculty surgeons to complete the 3-min survey. Facebook subjects (110) responded within 25 d. Language analysis indicated that crowdworkers who used negation words (i.e., “but,” “although,” and so forth) scored the performance more equivalently to experienced surgeons than crowdworkers who did not ( P < 0.00001). Conclusions For a robotic suturing performance, we have shown that surgery-naive crowdworkers can rapidly assess skill equivalent to experienced faculty surgeons using Crowd-Sourced Assessment of Technical Skill. It remains to be seen whether crowds can discriminate different levels of skill and can accurately assess human surgery performances.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Historically the elderly have been under-represented in non-ST-elevation myocardial infarction (NSTEMI) management trials.
The aim of this trial was to demonstrate that an intervention-guided ...strategy is superior to optimal medical therapy (OMT) alone for treating NSTEMI in elderly individuals.
Patients (≥80 years, chest pain, ischaemic ECG, and elevated troponin) were randomised 1:1 to an intervention-guided strategy plus OMT versus OMT alone. The primary endpoint was a composite of all-cause mortality and non-fatal myocardial reinfarction at 1 year. Ethics approval was obtained by the institutional review board of every recruiting centre.
From May 2014 to September 2018, 251 patients (n=125 invasive vs n=126 conservative) were enrolled. Almost 50% of participants were female. The trial was terminated prematurely due to slow recruitment. A Kaplan-Meier estimate of event-free survival revealed no difference in the primary endpoint at 1 year (invasive 18.5% 23/124 vs conservative 22.2% 28/126; p=0.39). No significant difference persisted after Cox proportional hazards regression analysis (hazard ratio 0.79, 95% confidence interval 0.45-1.35; p=0.39). There was greater freedom from angina at 3 months (p<0.001) after early intervention but this was similar at 1 year. Both non-fatal reinfarction (invasive 9.7% 12/124 vs conservative 14.3% 18/126; p=0.22) and unplanned revascularisation (invasive 1.6% 2/124 vs conservative 6.4% 8/126; p=0.10) occurred more frequently in the OMT alone cohort.
An intervention-guided strategy was not superior to OMT alone to treat very elderly NSTEMI patients. The trial was underpowered to demonstrate this definitively. Early intervention resulted in fewer cases of reinfarction and unplanned revascularisation but did not improve survival.
Surgical training has traditionally been one of apprenticeship, where the surgical trainee learns to perform surgery under the supervision of a trained surgeon. This is time consuming, costly, and of ...variable effectiveness. Training using a virtual reality simulator is an option to supplement standard training.
To determine whether virtual reality training can supplement or replace conventional laparoscopic surgical training (apprenticeship) in surgical trainees with limited or no prior laparoscopic experience.
We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and grey literature until March 2008.
We included all randomised clinical trials comparing virtual reality training versus other forms of training including video trainer training, no training, or standard laparoscopic training in surgical trainees with little or no prior laparoscopic experience. We also included trials comparing different methods of virtual reality training.
We collected the data on the characteristics of the trial, methodological quality of the trials, mortality, morbidity, conversion rate, operating time, and hospital stay. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. For each outcome we calculated the standardised mean difference with 95% confidence intervals based on intention-to-treat analysis.
We included 23 trials with 612 participants. Four trials compared virtual reality versus video trainer training. Twelve trials compared virtual reality versus no training or standard laparoscopic training. Four trials compared virtual reality, video trainer training and no training, or standard laparoscopic training. Three trials compared different methods of virtual reality training. Most of the trials were of high risk of bias. In trainees without prior surgical experience, virtual reality training decreased the time taken to complete a task, increased accuracy, and decreased errors compared with no training; virtual reality group was more accurate than video trainer training group. In the participants with limited laparoscopic experience, virtual reality training reduces operating time and error better than standard in the laparoscopic training group; composite operative performance score was better in the virtual reality group than in the video trainer group.
Virtual reality training can supplement standard laparoscopic surgical training of apprenticeship and is at least as effective as video trainer training in supplementing standard laparoscopic training. Further research of better methodological quality and more patient-relevant outcomes are needed.
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NUK, OILJ, UL, UM, UPUK, VSZLJ
Abstract We demonstrate a novel link between skilled immigration restrictions, corporate innovation, and industry consolidation. Binding restrictions on H1B visas are a shock to firms’ R&D labor ...supply, leading firms to shift R&D expenditures and employees overseas. Organizationally and financially constrained firms are less able to adjust to the restrictions. They reduce basic research and patenting, are less able to acquire other firms for intellectual property, and are more likely to exit. Industry concentration and firm-level markups increase when firms are better able to adjust. This increase in market power is an unintended consequence of skilled immigration restrictions.
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