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Practice in the simulated environment can improve surgical skills. However, the transfer of open complex surgical skills to the operating room is unclear. This study evaluated the effect of resident operative performance following a simulation experience on a hand-sewn small bowel anastomosis and determined the impact of utilizing proficiency-based training. Nine categorical interns performed a hand-sewn small bowel anastomosis in the operating room prior to (pre-test) and following (post-test) a 3-h simulation training session with an assessment at the end. Participants were randomly assigned to 1of 2 simulation training groups: proficiency-based or standard. Operative performance was videotaped. 2 independent, blinded faculty surgeons assessed performances by a global rating scale. Pre- and post-confidence levels were obtained on a 5-point Likert scale. Overall, pre-test and post-test operative performance was similar (3 [IQR, 2.5 –3.5] versus 3 [IQR, 3 –3], P = 0.59). Furthermore, no difference was observed in the post-test performance with proficiency-based or standard training (3 [IQR, 3 –3] versus 3 [IQR, 3 –3], P = 0.73). Self-reported confidence with the skills, however, significantly improved (median 1 versus 4, P = 0.007). In this prospective, randomized study, we did not observe an improvement in operative performance following simulation instruction and assessment, with both training groups. Overcoming barriers to skills transfer will be paramount in the future to optimize simulation training in general surgery. These findings highlight the importance of continued study for the ideal conditions and timing of technical skills training. [ABSTRACT FROM AUTHOR]

Contests are widely used as mechanisms to incentivize efforts in various contexts, from research innovation to athletic and employee performance. This paper builds an analytical model and provides empirical evidence to assess the effectiveness of a large-scale, real-world residential energy conservation contest in Vietnam. The model suggests that contests offering multiple prizes and requiring a minimum amount of effort can effectively promote conservation. It also identifies factors that influence the conservation effort, such as the cost of effort, size of prizes, and types of contestants. To empirically estimate the effect of the energy conservation contest, this paper uses a unique confidential dataset of monthly residential electricity usage with over 45 million observations. The results indicate that the contest significantly reduced electricity consumption among contestants, and the effect of the contest could persist for months after its conclusion, leading to an average abatement cost of $27 per ton of CO2 emissions. [ABSTRACT FROM AUTHOR]

• Generative activities (e.g., diagramming) after reading possibly improve monitoring. • We tested if feedback (correct diagram) further improves monitoring and text comprehension. • Participants adapted judgements of learning after receiving a correct diagram. • Diagramming + feedback improved monitoring accuracy and text comprehension. • Standards helped identify mistakes and prepare for the comprehension test. Accurate self-monitoring of text comprehension is critical for effective self-regulated learning from texts. Unfortunately, it has been repeatedly shown that students' monitoring of their text comprehension is often inaccurate, which can subsequently lead to inaccurate regulation and ineffective restudy decisions. Previous research provided evidence that completing causal diagrams at a delay after text reading (i.e., diagramming) can help to improve students' monitoring of text comprehension. However, even after diagramming, there is still substantial room for improvement. The current studies therefore aimed to test whether providing feedback in the form of a correctly completed diagram (i.e., performance standard) would further increase students' monitoring accuracy. In Study 1, 79 participants (aged 18–23) made judgements of learning under four conditions: I. No-Diagram (control), II. Standard-Only, III. Diagramming-Only, or IV. Diagramming + Standard. In each condition, students studied a text, made a judgement of learning before and after the experimental tasks, and completed a comprehension test at the end of each of the (overall six) trials. Results showed that only Diagramming + Standard improved monitoring accuracy and text comprehension. In Study 2, 20 undergraduate students (aged 18–23) completed the Diagramming + Standard condition while their eye movements were tracked and subsequently replayed for cued retrospective verbal reporting. The findings suggest that students used the standards to identify mistakes and improve their monitoring and text comprehension. [ABSTRACT FROM AUTHOR]

In recent times, the vibro-impact nonlinear energy sink (VINES) has emerged as a promising passive mechanism for vibration mitigation in engineering systems. The VINES system consists of a ball traveling within a cavity of an externally excited linear oscillator (LO). The ball impacts either end of the cavity, transferring energy from the LO to the ball and mitigating excess oscillations of the LO. Earlier studies of VINES analyzed scenarios with the mass of the ball to be small relative to the LO, with low forcing amplitude near the resonant frequency of the LO. Improvements in targeted energy transfer (TET), observed for an increased mass of the ball, motivate an investigation of VINES for larger mass ratios, using a recently developed semi-analytical map-based approach that provides the exact solution without the limitations of previous analyses. Complementary analytical and numerical approaches treat larger mass ratios and higher amplitudes of the external harmonic excitation for forcing frequencies away from the natural frequency of the LO, identifying parameter regimes for efficient and inefficient performance based on standard measures of energy transfer. The analysis identifies multiple regions for the desired behavior with two alternating impacts per forcing period and provides relevant stability conditions. Numerical results indicate chattering behavior in regimes where energy transfer is minimal, yielding performance that appears similar to resonance. This phenomenon can be directly related to the passive nature of the VINES design, where the natural frequency of the VINES system decreases as the mass of the ball, and thus that of the system, increases. Then the peak response of the LO is shifted away from its resonant frequency, allowing excellent energy transfer to be realized there. • Derived a semi-analytical map-based approach from the exact solutions for VINES system. • Investigation of efficient energy transfer through VINES for a wide range of parameter values, not necessarily small. • Analyzed the influence of excitation amplitude, impact phase and mass ratio. • Analyzed performance of VINES when system exhibits alternate chattering-type behavior. • Observed efficient TET away from the resonating frequency. [ABSTRACT FROM AUTHOR]

We present a new convolution layer for deep learning architectures which we call QuadConv — an approximation to continuous convolution via quadrature. Our operator is developed explicitly for use on non-uniform, mesh-based data, and accomplishes this by learning a continuous kernel that can be sampled at arbitrary locations. Moreover, the construction of our operator admits an efficient implementation which we detail and construct. As an experimental validation of our operator, we consider the task of compressing partial differential equation (PDE) simulation data from fixed meshes. We show that QuadConv can match the performance of standard discrete convolutions on uniform grid data by comparing a QuadConv autoencoder (QCAE) to a standard convolutional autoencoder (CAE). Further, we show that the QCAE can maintain this accuracy even on non-uniform data. In both cases, QuadConv also outperforms alternative unstructured convolution methods such as graph convolution. • A new convolution layer for deep learning architectures with unstructured data. • Convolutional operator learns a continuous kernel and a quadrature rule. • Convolutional layer used within autoencoders for unstructured PDE data compression. • Method leads to similar accuracy to CNN autoencoder on equivalent structured data. [ABSTRACT FROM AUTHOR]

Local and systemic contamination caused by metal ions leaching from medical device materials is a significant and continuing health problem. The increasing need for verification and validation, and the imposition of stringent government regulations to ensure that the products comply with the quality, safety, and performance standards, have led regulatory bodies worldwide to strongly recommend the use of modeling and simulation tools to support medical device submissions. A previously published physiologically based toxicokinetic (PBTK) model, is here expanded and enriched by an additional separate tissue compartment to better resemble normal physiology and by the introduction of time-dependent functions to describe all biokinetic parameters. The new model is exercised in conjunction with state-of-the-art probabilistic, Monte Carlo methodology to calculate the predictions' confidence intervals and incorporate variability associated with toxicological biodistribution studies. The quantitative consistency of the model-derived predictions is validated against reported data following the implantation of nickel-containing cardiovascular devices in humans and minipigs. Finally, a new methodology for compartmental toxicological risk assessment is presented that can be used for forward or reverse dosimetry. Our work is aimed at providing a computational tool to optimize the device design characteristics and safeguard that the substances released do not exceed permissible exposure limits. [Display omitted] • A compartmental PBTK model is proposed for Ni leaching from cardiovascular stents. • Method for calculating the confidence intervals for the model-derived predictions. • Demonstrated prognostic conformity with reported in vivo measurements. • Toxicological risk assessment for individual organs/tissues and biofluids. • Static in vitro immersion tests are proven inadequate to estimate in vivo release. [ABSTRACT FROM AUTHOR]

• We investigated the inversion principle in children with mathematical learning disabilities (MLD). • Arithmetic problems were presented in 2 presentation modes (symbolic or picture). • MLD children were able to use the inversion principle in picture mode only. • MLD children achieved performance equal to typically developing children in this mode. Numerical inversion is the ability to understand that addition is the opposite of subtraction and vice versa. Three-term arithmetic problems can be solved without calculation using this conceptual shortcut. To verify that this principle is used, inverse problems (a + b − b) can be compared with standard problems (a + b − c). If this principle is used, performance on inverse problems will be higher than performance on standard problems because no calculation is required. To our knowledge, this principle has not been previously studied in children with mathematical learning disabilities (MLD). Our objectives were (a) to study whether 10-year-olds with MLD are able to use this conceptual principle in three-term arithmetic problems and (b) to evaluate the impact of the presentation mode. A total of 64 children with or without MLD solved three-term arithmetic problems (inverse and standard) in two presentation modes (symbolic and picture). The results showed that even though children with MLD have difficulties in performing arithmetic problems, they can do so when the inverse problem is presented with pictures. The picture presentation mode allowed children with MLD to efficiently identify and use the conceptual inversion shortcut and thus to achieve a similar performance to that of typically developing children. These results provide interesting perspectives for the care of children with MLD. [ABSTRACT FROM AUTHOR]