Bin Zheng - Academia.edu (original) (raw)

Papers by Bin Zheng

Studies in health technology and informatics, 2006

An approach to enhance navigation task performance is to integrate sensory guidance (virtual fixt... more An approach to enhance navigation task performance is to integrate sensory guidance (virtual fixtures) into a virtual training system. To evaluate the effects of adding virtual fixtures to skill acquisition, 32 subjects were required to use a PHANToM input device, to transport a virtual object through a computer generated 3-D graphic maze. Subjects practiced navigation under 4 conditions: the maze was augmented with either a graphic fixture (G), attractive force field (F), both graphic and force field (GF), or no (N) virtual fixture. Fifteen practice trials were given before subjects were transferred to a situation with no virtual fixtures. Results showed that the implementation of the force field assisted task performance during practice; however, it failed to show positive transfer effects. In contrast, adding a graphic fixture to the virtual maze helped subjects to define the optimal pathway throughout navigation, which facilitated skill acquisition.

PsycEXTRA Dataset

Kinematics of reaching and grasping are observed for prehension performed by the hand (natural pr... more Kinematics of reaching and grasping are observed for prehension performed by the hand (natural prehension) and with a simple grasper held in the hand (remote prehension). Remote prehension is executed with a longer movement time, lower movement speed, extended deceleration phase and a relatively larger peak aperture compared to natural prehension. The kinematic changes in remote prehension are more pronounced when adults reached and grasped an object placed on a narrow than a wide base. Results suggested that the indirect and incomplete proprioception and sensorimotor integration with tool use are the main problems for movement control in remote manipulation. Implications of this study are discussed for design of tools and a safe work environment for tool use.

Biosensors

Pattern recognition using surface Electromyography (sEMG) applied on prosthesis control has attra... more Pattern recognition using surface Electromyography (sEMG) applied on prosthesis control has attracted much attention in these years. In most of the existing methods, the sEMG signal during the firmly grasped period is used for grasp classification because good performance can be achieved due to its relatively stable signal. However, using the only the firmly grasped period may cause a delay to control the prosthetic hand gestures. Regarding this issue, we explored how grasp classification accuracy changes during the reaching and grasping process, and identified the period that can leverage the grasp classification accuracy and the earlier grasp detection. We found that the grasp classification accuracy increased along the hand gradually grasping the object till firmly grasped, and there is a sweet period before firmly grasped period, which could be suitable for early grasp classification with reduced delay. On top of this, we also explored corresponding training strategies for bette...

Proceedings of the 30th ACM Conference on User Modeling, Adaptation and Personalization

A large part of health education involves acquiring operational skills that require continued coo... more A large part of health education involves acquiring operational skills that require continued cooperation from the sense of sight. Traditional skill-training systems heavily rely on post-task evaluation and cannot automatically identify the tacit knowledge (e.g., visual attention allocation) that is used to support the decisionmaking and tool manipulation process. Recent research has started addressing this issue by identifying learner behaviours to understand learner needs and respond with personalized real-time support. To enable this type of adaptivity when training people in how to give injections, we conducted a study to investigate user's visual attention. We analyzed the eye-tracking data of 8 skilled medical practitioners and 10 student nurses from when they were performing an injection task on a simulated abdominal pad. Differences in the detected visual attention and eye-scan patterns across expertise levels create an opportunity for using overlay models or other diagnosis approaches to provide adaptive support to nurse trainees. CCS CONCEPTS • Human-centered computing → Human computer interaction (HCI); HCI design and evaluation methods; User models.

Cancer Management and Research, 2020

Background: Gastric cancer (GC) is a highly occurring cancer with poor prognosis. Reports indicat... more Background: Gastric cancer (GC) is a highly occurring cancer with poor prognosis. Reports indicate that long non-coding RNA (LncRNA) potentially regulates tumor progression. Herein, we aim to explore the effect of LncRNA AC118344.1 on the progression of gastric cancer. Methods: Overexpression and knockout experiments were used to clarify the potential molecular signaling mechanisms induced by AC118344.1. CCK-8, transwell and in vivo metastasis assay were used to detect the function of AC118344.1 in AGS and SGC-7901 cells. Additionally, shRNA silencing techniques, qRT-PCR and Western blot assay were used to explore the relationship between AC118344.1, AKT2, and its downstream molecules. Results: Upregulating the expression of AC118344.1 induces cell proliferation, invasion in vitro, and lung metastasis in vivo whereas downregulating the expression of AC118344.1 inhibits these effects. Besides, silencing the expression of AC118344.1 downregulated the expression of AKT2 in both the two cells. On the other hand, silencing the expression of AKT2 by shRNA was unable to downregulate the expression of AC118344.1 in both the gastric cancer cells. Also, AC118344.1 regulated AKT2 via its downstream molecules including HK2 and MMP2. Conclusion: AC118344.1 promotes gastric cancer cell proliferation and invasion and lung metastasis in nude mice by upregulating the expression of AKT2 and its downstream molecules (HK2 and MMP2). Therefore, our findings provide a novel mechanism of the AC118344.1-AKT2-HK2/MMP2 axis in regulating the development of gastric cancer cells.

IEEE journal of translational engineering in health and medicine, 2018

The objective of this paper was to examine the changes in applied force and rate of chest compres... more The objective of this paper was to examine the changes in applied force and rate of chest compression (CC) during 5 min of CC with a target CC rate of 90/min (CC90) or 120/min (CC120) with and without metronome guidance during simulated neonatal cardiopulmonary resuscitation (CPR). We performed a randomized controlled manikin trial. Fourteen neonatal resuscitation program providers performed CC90 and CC120 with or without a metronome in a randomized order. Peak and residual leaning force and CC rate each minute of CPR were analyzed with Friedman's analysis of variance (ANOVA) (within interventions) and two-way repeated measures ANOVA (between interventions). There was a large variability in force application, with no difference between groups. Peak and residual leaning forces in CC90 and CC120 did not change with time with or without a metronome. The CC rate increased with time in all groups except CC90 without a metronome. In conclusion, neither the target CC rate nor using a m...

Journal of Medical Systems, 2016

We introduce a smart sensor-based motion detection technique for objective measurement and assess... more We introduce a smart sensor-based motion detection technique for objective measurement and assessment of surgical dexterity among users at different experience levels. The goal is to allow trainees to evaluate their performance based on a reference model shared through communication technology, e.g., the Internet, without the physical presence of an evaluating surgeon. While in the current implementation we used a Leap Motion Controller to obtain motion data for analysis, our technique can be applied to motion data captured by other smart sensors, e.g., OptiTrack. To differentiate motions captured from different participants, measurement and assessment in our approach are achieved using two strategies: (1) low level descriptive statistical analysis, and (2) Hidden Markov Model (HMM) classification. This article is part of the Topical Collection on Education & Training

Surgical Endoscopy, 2009

Background Laparoscopic instruments are rigid and thus cannot provide the degrees of freedom (DOF... more Background Laparoscopic instruments are rigid and thus cannot provide the degrees of freedom (DOF) needed by a surgeon in certain situations. A new generation of laparoscopic instruments with the ability to articulate their end effectors is available. Although these instruments offer the flexibility needed to perform complex tasks in a constricted surgical site, their control may be hampered by their increased complexity. Methods This study compared the task performance between articulating and conventional laparoscopic instruments. Surgeons with extensive laparoscopic experience (8 experts) and staff with no surgical experience (8 novices) were recruited for the test. Both groups were required to perform three standardized tasks (peg transfer, left-to-right suturing, and up-and-down suturing) in a bench top model using conventional and articulating instruments. Performance was scored using a standardized 100-point scale based on movement speed and accuracy. After the initial trials with conventional and articulating instruments, each participant was given a short orientation on how to use the articulating instrument advantageously. The participant then was retested with the articulating instrument. Results As expected, the expert group scored significantly better than the novice group (p \ 0.001). The combined data from both groups showed better performance with the conventional instruments than with the articulating instruments (p = 0.074). The experts maintained their proficient laparoscopic performance using conventional instruments in their first attempts with the articulating instruments (91 vs. 84), whereas the novices had greater difficulty with the articulating instruments than with the conventional instruments (46 vs. 59). After a short orientation, however, the novices outscored the expert group in terms of net improvement in performance with the articulating instrument (27 vs. 1% improvement). Conclusion Experienced surgeons are readily able to transfer their skills from conventional to articulating laparoscopic instruments. To speed the learning process, the use of articulating instruments can be started at an early stage of surgical training.

Surgical Innovation, 2015

Introduction. Eye tracking has been widely used in studying the eye behavior of surgeons in the p... more Introduction. Eye tracking has been widely used in studying the eye behavior of surgeons in the past decade. Most eye-tracking data are reported in a 2-dimensional (2D) fashion, and data for describing surgeons’ behaviors on stereoperception are often missed. With the introduction of stereoscopes in laparoscopic procedures, there is an increasing need for studying the depth perception of surgeons under 3D image-guided surgery. Methods. We developed a new algorithm for the computation of convergence points in stereovision by measuring surgeons’ interpupillary distance, the distance to the view target, and the difference between gaze locations of the 2 eyes. To test the feasibility of our new algorithm, we recruited 10 individuals to watch stereograms using binocular disparity and asked them to develop stereoperception using a cross-eyed viewing technique. Participants’ eye motions were recorded by the Tobii eye tracker while they performed the trials. Convergence points between norma...

Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, 2014

Pupil size is known to correlate with the changes of cognitive task workloads, but how the pupil ... more Pupil size is known to correlate with the changes of cognitive task workloads, but how the pupil responds to requirements of basic goal-directed motor tasks involved in human-machine interactions is not yet clear. This work conducted a user study to investigate the pupil dilations during aiming in a tele-operation setting, with the purpose of better understanding how the changes in task requirements are reflected by the changes of pupil size. The task requirements, managed by Fitts' index of difficulty (ID), i.e. the size and distance apart of the targets, were varied between tasks, and pupil responses to different task IDs were recorded. The results showed that pupil diameter can be employed as an indicator of task requirements in goal-directed movements-higher task difficulty evoked higher valley to peak pupil dilation, and the peak pupil dilation occurred after a longer delay. These findings contribute to the foundation for developing methods to objectively evaluate interactive task requirements using pupil parameters during goal-directed movements in HCI.

Proceedings of the Symposium on Eye Tracking Research and Applications, 2014

Novices were trained to perform a unimanual peg transport task in a laparoscopic training box wit... more Novices were trained to perform a unimanual peg transport task in a laparoscopic training box with an illuminated interior displayed on a monitor. Subjects were divided into two groups; one group was verbally instructed to direct their gaze at distant targets, while the other group had their gaze behaviour implicitly manipulated using distant target illumination. Both groups achieved similar task completion times post-training and developed peripheral vision strategies leading to delayed foveation on targets until the instrument was closer to its destination, although the ability to focus on targets earlier during manual movements as done by an expert surgeon was quickly regained by the verbal instruction group post-training. This suggests that care should be taken when employing visual attention cuing methods such as target highlighting for training eye-hand coordination skills, as simple verbal instruction may be sufficient to help trainees to adopt more expert-like gaze behaviours.

Proceedings of the Symposium on Eye Tracking Research and Applications, 2014

Pupil size is known to correlate with changes of cognitive task workloads, but the pupillary resp... more Pupil size is known to correlate with changes of cognitive task workloads, but the pupillary response to requirements of basic goaldirected motor tasks is not yet clear, although pointing with tools is a ubiquitous human task. This work describes a user study to investigate the pupil dilations during aiming in two tele-operation tasks with different target settings, one aiming at targets with different sizes located at constant distance apart, and the other aiming at targets varying in different distances. The task requirements in each task were defined by Fitts' index of difficulty (ID). The purpose of this work is to further explore how the changes in task requirements are reflected by the changes of pupil size, i.e., whether the pupil responds to either target size or target distance, or to both of them. Pupil responses to different task IDs were recorded in each task. The results showed that the pupil responds to the changes of ID, not just to the change of target size. This implies that pupil diameter can be employed as an indicator of task requirement in goal-directed movements, because higher task difficulty evoked higher peak pupil dilation which occurred with longer delay. These findings can be used for detailed understanding of eye-hand coordination mechanisms in interactive systems and contribute to the foundation for developing methods to objectively evaluate interactive task requirements using pupil parameters during goal-directed movements.

Proceedings of the Symposium on Eye Tracking Research and Applications, 2012

For gaze-based training in surgery to be meaningful, the similarity between a trainee's gaze and ... more For gaze-based training in surgery to be meaningful, the similarity between a trainee's gaze and an expert's gaze during performance of surgical tasks must be assessed. As it is difficult to record two people's gaze simultaneously, we produced task videos made by experts, and measured the amount of overlap between the gaze path of the expert surgeon and third-party observers while watching the videos. For this investigation, we developed a new, simple method for displaying and summarizing the proportion of time during which two observers' points of gaze on a common stimulus were separated by no more than a specified visual angle. In a study of single-observer self-review and multiple-observer initial view of a laparoscopic training task, we predicted that selfreview would produce the highest overlap. We found relatively low overlap between watchers and the task performer; even operators with detailed task knowledge produce low overlap when watching their own videos. Conversely, there was a high overlap among all watchers. Results indicate that it may be insufficient to improve trainees' eye-hand coordination by just watching a video. Gaze training will need to be integrated with other teaching methods to be effective.

Simulation in Healthcare: The Journal of the Society for Simulation in Healthcare, 2012

The rapid uptake of simulation-based education has led to the development of simulation programs ... more The rapid uptake of simulation-based education has led to the development of simulation programs and centers all around the world. Unfortunately, many of these centers are functioning as localized silos and not taking advantage of the potential for collaboration with other regional centers to promote interprofessional education. In the province of British Columbia (BC), Canada, 38 institutions, including health care authorities, universities, colleges, and other health-related organizations, have participated in assessing the use of simulation in BC and in developing a provincial model that enables collaboration and interprofessional learning at the provincial level. This article describes methods and results of a needs assessment and discusses an interprofessional simulation in health care educational model that provides access for all health care professionals in BC regardless of their geographic location and/or institutional affiliation. We anticipate that this information will be useful to and supportive of others in developing simulation collaborations in their respective regions.

Surgical Innovation, 2008

and ineffective teamwork have been identified as the primary source of many adverse medical outco... more and ineffective teamwork have been identified as the primary source of many adverse medical outcomes. 7 Conversely, effective communication has been shown to reduce medical errors. 8 We report a prospective study on the impact of verbal communication on team performance for a surgical team performing laparoscopic tasks in a simulated training system. In this study, the team performance was analyzed between 2 laparoscopic groups comprised of personnel with minimal laparoscopic skills. The feedback group was provided with sufficient verbal instruction, and feedback from an instructor, was compared with the control group with minimal or no feedback. Our hypothesis was that team performance in the surgical teams with sufficient verbal instruction, and feedback would be more efficient than teams with minimal or no verbal information. Methods Participants and Study Groups A total of 24 dyad teams were recruited from Minimally Invasive Surgery Program of Legacy Health System A ccording to the American College of Surgeons, adverse outcomes remain as a source of patient morbidity, excess cost, and litigation. 1 Recent studies on adverse events in medical practice have revealed a weak link between the increase of surgeons' technical skills and a decrease of incidence of surgical errors. The occurrence of medical errors is more strongly associated with failures of nontechnical skills of the surgeons. 2-4 These nontechnical skills include communication, decision making, situational awareness, and teamwork. 3 Failures of communication in surgery contribute up to 43% of surgical errors. 5 One multicenter study on patient outcomes in the intensive care unit showed that part of the difference in mortality was directly related to the level of interaction and coordination between staff. 6 Poor communication skills The impact of verbal communication on laparoscopic team performance was examined. A total of 24 dyad teams, comprisied of residents, medical students, and office staff, underwent 2 team tasks using a previously validated bench model. Twelve teams (feedback groups) received instant verbal instruction and feedback on their performance from an instructor which was compared with 12 teams (control groups) with minimal or no verbal feedback. Their performances were both video and audio taped for analysis. Surgical backgrounds were similar between feedback and control groups. Teams with more verbal feedback achieved significantly better task performance (P = .002) compared with the control group with less feedback. Impact of verbal feedback was more pronounced for tasks requiring team cooperation (aiming and navigation) than tasks depending on individual skills (knotting). Verbal communication, especially the instructions and feedback from an experienced instructor, improved team efficiency and performance.

Surgical Endoscopy, 2013

Background Previous studies on surgical team composition have shown that surgical team size had a... more Background Previous studies on surgical team composition have shown that surgical team size had an independent impact on surgical performance in US and Canadian hospitals. We aimed to investigate the impact of team composition on surgical performance in two Chinese hospitals. Methods General surgery procedures performed from April 2011 to June 2012 were retrospectively reviewed to record the number of attendees in the operating room (OR) and the procedure time (PT). Results A total of 1,900 valid procedures, mostly laparoscopic, were performed during the study period. The mean PT was 90.5 min. On average, there were a total of 6 (range = 3-8) team members per procedure: 3 (range = 1-5) surgeons, 2 nurses, and 1 anesthesiologist. Unlike the data reported for the US and Canada, the number of nurses and anesthesiologists remained stable in most cases, whereas the number of surgeons differed by procedure. Multiple-regression analysis revealed that both the complexity of the operation and the team size significantly affected PT. When procedure complexity and patient condition were kept constant, adding one team member in our data analysis predicted an increase of 34.7 min in the PT. Conclusion The surgical team size has a measurable effect on PT. Aside from surgical complexity, the team composition and member stability affected PT in the OR. Optimizing surgical teams and developing a strategy to maintain team stability are of great importance for improving OR efficiency.

Surgical Endoscopy, 2012

Background In preparing for the fundamentals of laparoscopic surgery (FLS) exam, residents usuall... more Background In preparing for the fundamentals of laparoscopic surgery (FLS) exam, residents usually adopt a self-learning strategy where practice time can be managed with more flexibility. However, with this self-learning strategy, there is a lack of direct supervision from experts and residents risk understudying for this high-stakes exam. Our objective is to determine study goals for effective selfguided practice for the FLS manual skills tasks that will result in passing the examination. Methods FLS manual skills data for all PGY-5 residents during 2009-2010 was supplied by the FLS administrative office. Descriptive statistics were performed, and data were regrouped by the pass/fail results of the exam. The minimum practice time requirement for passing each manual skills task is reported in order to guide practice. Results 1,047 proctored FLS exams were completed by 2009-2010 residents. Mean task time achieved by all residents was 84 ± 31 s for peg transfer, 139 ± 54 s for pattern cut, 78 ± 29 s for endoloop, 158 ± 66 s for extracorporeal suturing, and 168 ± 77 s for intracorporeal suturing. In the pass group (n = 988), mean time to complete each task was 80 s for peg transfer, 134 s for pattern cut, 75 s for endoloop, 148 s for extracorporeal suturing, and 160 s for intracorporeal suturing. Calculations suggest a self-study goal for each task of 53 s for peg transfer, 50 s for pattern cut, 87 s for endoloop, 99 s for extracorporeal suturing, and 96 s for intracorporeal suturing. If a resident can reliably achieve these results during self-study, they have an 84 % chance of passing the exam. Conclusions Residents preparing to take the FLS exam can refer to data presented in this study to set practice goals. Referring to these data-based practice goals will help residents to improve their chances of passing this highstakes exam.

Surgical Endoscopy, 2009

Background This video-aided observational study was conducted to examine team cooperation among s... more Background This video-aided observational study was conducted to examine team cooperation among surgeons in a surgical team built up with different time lengths. We predicted that the surgeons in a team that has longer teamwork experience would perform more anticipatory movements than surgeons in a surgical team that is newly formed. Methods Laparoscopic Nissen fundoplication cases were videotaped with both surgical view and the OR view. An anticipatory movement was identified when a surgeon manually provided direct assistance for an upcoming task without a request by other surgeons in the team. Result A total of 28 cases of laparoscopic Nissen fundoplication were videotaped and analyzed. Fifteen operations were performed by surgeons collaborating as a team for 10 weeks, in contrast to 13 operations performed by surgeons paired up for less than 5 weeks. Significantly more anticipatory movements were performed by the surgeons in the dedicated team (22 counts) than by those in the developing team (19 counts, p = 0.029). However, the OR time was not significantly different (dedicated team = 111 min, developing team = 115 min, p = 0.611) between the two teams which suggests that other types of coordination would also influence surgical teamwork. Conclusion Working in a team allows surgeons to develop sophisticated cognition to anticipate an upcoming task and provide assistance without verbal communication. The greater number of anticipatory movements observed in the dedicated surgical team suggests that anticipatory movement can be a valuable measure for team cooperation. Further research with a larger number of cases is needed to see whether performance of more anticipatory movements does shorten OR time.

Studies in health technology and informatics, 2006

An approach to enhance navigation task performance is to integrate sensory guidance (virtual fixt... more An approach to enhance navigation task performance is to integrate sensory guidance (virtual fixtures) into a virtual training system. To evaluate the effects of adding virtual fixtures to skill acquisition, 32 subjects were required to use a PHANToM input device, to transport a virtual object through a computer generated 3-D graphic maze. Subjects practiced navigation under 4 conditions: the maze was augmented with either a graphic fixture (G), attractive force field (F), both graphic and force field (GF), or no (N) virtual fixture. Fifteen practice trials were given before subjects were transferred to a situation with no virtual fixtures. Results showed that the implementation of the force field assisted task performance during practice; however, it failed to show positive transfer effects. In contrast, adding a graphic fixture to the virtual maze helped subjects to define the optimal pathway throughout navigation, which facilitated skill acquisition.

PsycEXTRA Dataset

Kinematics of reaching and grasping are observed for prehension performed by the hand (natural pr... more Kinematics of reaching and grasping are observed for prehension performed by the hand (natural prehension) and with a simple grasper held in the hand (remote prehension). Remote prehension is executed with a longer movement time, lower movement speed, extended deceleration phase and a relatively larger peak aperture compared to natural prehension. The kinematic changes in remote prehension are more pronounced when adults reached and grasped an object placed on a narrow than a wide base. Results suggested that the indirect and incomplete proprioception and sensorimotor integration with tool use are the main problems for movement control in remote manipulation. Implications of this study are discussed for design of tools and a safe work environment for tool use.

Biosensors

Pattern recognition using surface Electromyography (sEMG) applied on prosthesis control has attra... more Pattern recognition using surface Electromyography (sEMG) applied on prosthesis control has attracted much attention in these years. In most of the existing methods, the sEMG signal during the firmly grasped period is used for grasp classification because good performance can be achieved due to its relatively stable signal. However, using the only the firmly grasped period may cause a delay to control the prosthetic hand gestures. Regarding this issue, we explored how grasp classification accuracy changes during the reaching and grasping process, and identified the period that can leverage the grasp classification accuracy and the earlier grasp detection. We found that the grasp classification accuracy increased along the hand gradually grasping the object till firmly grasped, and there is a sweet period before firmly grasped period, which could be suitable for early grasp classification with reduced delay. On top of this, we also explored corresponding training strategies for bette...

Proceedings of the 30th ACM Conference on User Modeling, Adaptation and Personalization

A large part of health education involves acquiring operational skills that require continued coo... more A large part of health education involves acquiring operational skills that require continued cooperation from the sense of sight. Traditional skill-training systems heavily rely on post-task evaluation and cannot automatically identify the tacit knowledge (e.g., visual attention allocation) that is used to support the decisionmaking and tool manipulation process. Recent research has started addressing this issue by identifying learner behaviours to understand learner needs and respond with personalized real-time support. To enable this type of adaptivity when training people in how to give injections, we conducted a study to investigate user's visual attention. We analyzed the eye-tracking data of 8 skilled medical practitioners and 10 student nurses from when they were performing an injection task on a simulated abdominal pad. Differences in the detected visual attention and eye-scan patterns across expertise levels create an opportunity for using overlay models or other diagnosis approaches to provide adaptive support to nurse trainees. CCS CONCEPTS • Human-centered computing → Human computer interaction (HCI); HCI design and evaluation methods; User models.

Cancer Management and Research, 2020

Background: Gastric cancer (GC) is a highly occurring cancer with poor prognosis. Reports indicat... more Background: Gastric cancer (GC) is a highly occurring cancer with poor prognosis. Reports indicate that long non-coding RNA (LncRNA) potentially regulates tumor progression. Herein, we aim to explore the effect of LncRNA AC118344.1 on the progression of gastric cancer. Methods: Overexpression and knockout experiments were used to clarify the potential molecular signaling mechanisms induced by AC118344.1. CCK-8, transwell and in vivo metastasis assay were used to detect the function of AC118344.1 in AGS and SGC-7901 cells. Additionally, shRNA silencing techniques, qRT-PCR and Western blot assay were used to explore the relationship between AC118344.1, AKT2, and its downstream molecules. Results: Upregulating the expression of AC118344.1 induces cell proliferation, invasion in vitro, and lung metastasis in vivo whereas downregulating the expression of AC118344.1 inhibits these effects. Besides, silencing the expression of AC118344.1 downregulated the expression of AKT2 in both the two cells. On the other hand, silencing the expression of AKT2 by shRNA was unable to downregulate the expression of AC118344.1 in both the gastric cancer cells. Also, AC118344.1 regulated AKT2 via its downstream molecules including HK2 and MMP2. Conclusion: AC118344.1 promotes gastric cancer cell proliferation and invasion and lung metastasis in nude mice by upregulating the expression of AKT2 and its downstream molecules (HK2 and MMP2). Therefore, our findings provide a novel mechanism of the AC118344.1-AKT2-HK2/MMP2 axis in regulating the development of gastric cancer cells.

IEEE journal of translational engineering in health and medicine, 2018

The objective of this paper was to examine the changes in applied force and rate of chest compres... more The objective of this paper was to examine the changes in applied force and rate of chest compression (CC) during 5 min of CC with a target CC rate of 90/min (CC90) or 120/min (CC120) with and without metronome guidance during simulated neonatal cardiopulmonary resuscitation (CPR). We performed a randomized controlled manikin trial. Fourteen neonatal resuscitation program providers performed CC90 and CC120 with or without a metronome in a randomized order. Peak and residual leaning force and CC rate each minute of CPR were analyzed with Friedman's analysis of variance (ANOVA) (within interventions) and two-way repeated measures ANOVA (between interventions). There was a large variability in force application, with no difference between groups. Peak and residual leaning forces in CC90 and CC120 did not change with time with or without a metronome. The CC rate increased with time in all groups except CC90 without a metronome. In conclusion, neither the target CC rate nor using a m...

Journal of Medical Systems, 2016

We introduce a smart sensor-based motion detection technique for objective measurement and assess... more We introduce a smart sensor-based motion detection technique for objective measurement and assessment of surgical dexterity among users at different experience levels. The goal is to allow trainees to evaluate their performance based on a reference model shared through communication technology, e.g., the Internet, without the physical presence of an evaluating surgeon. While in the current implementation we used a Leap Motion Controller to obtain motion data for analysis, our technique can be applied to motion data captured by other smart sensors, e.g., OptiTrack. To differentiate motions captured from different participants, measurement and assessment in our approach are achieved using two strategies: (1) low level descriptive statistical analysis, and (2) Hidden Markov Model (HMM) classification. This article is part of the Topical Collection on Education & Training

Surgical Endoscopy, 2009

Background Laparoscopic instruments are rigid and thus cannot provide the degrees of freedom (DOF... more Background Laparoscopic instruments are rigid and thus cannot provide the degrees of freedom (DOF) needed by a surgeon in certain situations. A new generation of laparoscopic instruments with the ability to articulate their end effectors is available. Although these instruments offer the flexibility needed to perform complex tasks in a constricted surgical site, their control may be hampered by their increased complexity. Methods This study compared the task performance between articulating and conventional laparoscopic instruments. Surgeons with extensive laparoscopic experience (8 experts) and staff with no surgical experience (8 novices) were recruited for the test. Both groups were required to perform three standardized tasks (peg transfer, left-to-right suturing, and up-and-down suturing) in a bench top model using conventional and articulating instruments. Performance was scored using a standardized 100-point scale based on movement speed and accuracy. After the initial trials with conventional and articulating instruments, each participant was given a short orientation on how to use the articulating instrument advantageously. The participant then was retested with the articulating instrument. Results As expected, the expert group scored significantly better than the novice group (p \ 0.001). The combined data from both groups showed better performance with the conventional instruments than with the articulating instruments (p = 0.074). The experts maintained their proficient laparoscopic performance using conventional instruments in their first attempts with the articulating instruments (91 vs. 84), whereas the novices had greater difficulty with the articulating instruments than with the conventional instruments (46 vs. 59). After a short orientation, however, the novices outscored the expert group in terms of net improvement in performance with the articulating instrument (27 vs. 1% improvement). Conclusion Experienced surgeons are readily able to transfer their skills from conventional to articulating laparoscopic instruments. To speed the learning process, the use of articulating instruments can be started at an early stage of surgical training.

Surgical Innovation, 2015

Introduction. Eye tracking has been widely used in studying the eye behavior of surgeons in the p... more Introduction. Eye tracking has been widely used in studying the eye behavior of surgeons in the past decade. Most eye-tracking data are reported in a 2-dimensional (2D) fashion, and data for describing surgeons’ behaviors on stereoperception are often missed. With the introduction of stereoscopes in laparoscopic procedures, there is an increasing need for studying the depth perception of surgeons under 3D image-guided surgery. Methods. We developed a new algorithm for the computation of convergence points in stereovision by measuring surgeons’ interpupillary distance, the distance to the view target, and the difference between gaze locations of the 2 eyes. To test the feasibility of our new algorithm, we recruited 10 individuals to watch stereograms using binocular disparity and asked them to develop stereoperception using a cross-eyed viewing technique. Participants’ eye motions were recorded by the Tobii eye tracker while they performed the trials. Convergence points between norma...

Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, 2014

Pupil size is known to correlate with the changes of cognitive task workloads, but how the pupil ... more Pupil size is known to correlate with the changes of cognitive task workloads, but how the pupil responds to requirements of basic goal-directed motor tasks involved in human-machine interactions is not yet clear. This work conducted a user study to investigate the pupil dilations during aiming in a tele-operation setting, with the purpose of better understanding how the changes in task requirements are reflected by the changes of pupil size. The task requirements, managed by Fitts' index of difficulty (ID), i.e. the size and distance apart of the targets, were varied between tasks, and pupil responses to different task IDs were recorded. The results showed that pupil diameter can be employed as an indicator of task requirements in goal-directed movements-higher task difficulty evoked higher valley to peak pupil dilation, and the peak pupil dilation occurred after a longer delay. These findings contribute to the foundation for developing methods to objectively evaluate interactive task requirements using pupil parameters during goal-directed movements in HCI.

Proceedings of the Symposium on Eye Tracking Research and Applications, 2014

Novices were trained to perform a unimanual peg transport task in a laparoscopic training box wit... more Novices were trained to perform a unimanual peg transport task in a laparoscopic training box with an illuminated interior displayed on a monitor. Subjects were divided into two groups; one group was verbally instructed to direct their gaze at distant targets, while the other group had their gaze behaviour implicitly manipulated using distant target illumination. Both groups achieved similar task completion times post-training and developed peripheral vision strategies leading to delayed foveation on targets until the instrument was closer to its destination, although the ability to focus on targets earlier during manual movements as done by an expert surgeon was quickly regained by the verbal instruction group post-training. This suggests that care should be taken when employing visual attention cuing methods such as target highlighting for training eye-hand coordination skills, as simple verbal instruction may be sufficient to help trainees to adopt more expert-like gaze behaviours.

Proceedings of the Symposium on Eye Tracking Research and Applications, 2014

Pupil size is known to correlate with changes of cognitive task workloads, but the pupillary resp... more Pupil size is known to correlate with changes of cognitive task workloads, but the pupillary response to requirements of basic goaldirected motor tasks is not yet clear, although pointing with tools is a ubiquitous human task. This work describes a user study to investigate the pupil dilations during aiming in two tele-operation tasks with different target settings, one aiming at targets with different sizes located at constant distance apart, and the other aiming at targets varying in different distances. The task requirements in each task were defined by Fitts' index of difficulty (ID). The purpose of this work is to further explore how the changes in task requirements are reflected by the changes of pupil size, i.e., whether the pupil responds to either target size or target distance, or to both of them. Pupil responses to different task IDs were recorded in each task. The results showed that the pupil responds to the changes of ID, not just to the change of target size. This implies that pupil diameter can be employed as an indicator of task requirement in goal-directed movements, because higher task difficulty evoked higher peak pupil dilation which occurred with longer delay. These findings can be used for detailed understanding of eye-hand coordination mechanisms in interactive systems and contribute to the foundation for developing methods to objectively evaluate interactive task requirements using pupil parameters during goal-directed movements.

Proceedings of the Symposium on Eye Tracking Research and Applications, 2012

For gaze-based training in surgery to be meaningful, the similarity between a trainee's gaze and ... more For gaze-based training in surgery to be meaningful, the similarity between a trainee's gaze and an expert's gaze during performance of surgical tasks must be assessed. As it is difficult to record two people's gaze simultaneously, we produced task videos made by experts, and measured the amount of overlap between the gaze path of the expert surgeon and third-party observers while watching the videos. For this investigation, we developed a new, simple method for displaying and summarizing the proportion of time during which two observers' points of gaze on a common stimulus were separated by no more than a specified visual angle. In a study of single-observer self-review and multiple-observer initial view of a laparoscopic training task, we predicted that selfreview would produce the highest overlap. We found relatively low overlap between watchers and the task performer; even operators with detailed task knowledge produce low overlap when watching their own videos. Conversely, there was a high overlap among all watchers. Results indicate that it may be insufficient to improve trainees' eye-hand coordination by just watching a video. Gaze training will need to be integrated with other teaching methods to be effective.

Simulation in Healthcare: The Journal of the Society for Simulation in Healthcare, 2012

The rapid uptake of simulation-based education has led to the development of simulation programs ... more The rapid uptake of simulation-based education has led to the development of simulation programs and centers all around the world. Unfortunately, many of these centers are functioning as localized silos and not taking advantage of the potential for collaboration with other regional centers to promote interprofessional education. In the province of British Columbia (BC), Canada, 38 institutions, including health care authorities, universities, colleges, and other health-related organizations, have participated in assessing the use of simulation in BC and in developing a provincial model that enables collaboration and interprofessional learning at the provincial level. This article describes methods and results of a needs assessment and discusses an interprofessional simulation in health care educational model that provides access for all health care professionals in BC regardless of their geographic location and/or institutional affiliation. We anticipate that this information will be useful to and supportive of others in developing simulation collaborations in their respective regions.

Surgical Innovation, 2008

and ineffective teamwork have been identified as the primary source of many adverse medical outco... more and ineffective teamwork have been identified as the primary source of many adverse medical outcomes. 7 Conversely, effective communication has been shown to reduce medical errors. 8 We report a prospective study on the impact of verbal communication on team performance for a surgical team performing laparoscopic tasks in a simulated training system. In this study, the team performance was analyzed between 2 laparoscopic groups comprised of personnel with minimal laparoscopic skills. The feedback group was provided with sufficient verbal instruction, and feedback from an instructor, was compared with the control group with minimal or no feedback. Our hypothesis was that team performance in the surgical teams with sufficient verbal instruction, and feedback would be more efficient than teams with minimal or no verbal information. Methods Participants and Study Groups A total of 24 dyad teams were recruited from Minimally Invasive Surgery Program of Legacy Health System A ccording to the American College of Surgeons, adverse outcomes remain as a source of patient morbidity, excess cost, and litigation. 1 Recent studies on adverse events in medical practice have revealed a weak link between the increase of surgeons' technical skills and a decrease of incidence of surgical errors. The occurrence of medical errors is more strongly associated with failures of nontechnical skills of the surgeons. 2-4 These nontechnical skills include communication, decision making, situational awareness, and teamwork. 3 Failures of communication in surgery contribute up to 43% of surgical errors. 5 One multicenter study on patient outcomes in the intensive care unit showed that part of the difference in mortality was directly related to the level of interaction and coordination between staff. 6 Poor communication skills The impact of verbal communication on laparoscopic team performance was examined. A total of 24 dyad teams, comprisied of residents, medical students, and office staff, underwent 2 team tasks using a previously validated bench model. Twelve teams (feedback groups) received instant verbal instruction and feedback on their performance from an instructor which was compared with 12 teams (control groups) with minimal or no verbal feedback. Their performances were both video and audio taped for analysis. Surgical backgrounds were similar between feedback and control groups. Teams with more verbal feedback achieved significantly better task performance (P = .002) compared with the control group with less feedback. Impact of verbal feedback was more pronounced for tasks requiring team cooperation (aiming and navigation) than tasks depending on individual skills (knotting). Verbal communication, especially the instructions and feedback from an experienced instructor, improved team efficiency and performance.

Surgical Endoscopy, 2013

Background Previous studies on surgical team composition have shown that surgical team size had a... more Background Previous studies on surgical team composition have shown that surgical team size had an independent impact on surgical performance in US and Canadian hospitals. We aimed to investigate the impact of team composition on surgical performance in two Chinese hospitals. Methods General surgery procedures performed from April 2011 to June 2012 were retrospectively reviewed to record the number of attendees in the operating room (OR) and the procedure time (PT). Results A total of 1,900 valid procedures, mostly laparoscopic, were performed during the study period. The mean PT was 90.5 min. On average, there were a total of 6 (range = 3-8) team members per procedure: 3 (range = 1-5) surgeons, 2 nurses, and 1 anesthesiologist. Unlike the data reported for the US and Canada, the number of nurses and anesthesiologists remained stable in most cases, whereas the number of surgeons differed by procedure. Multiple-regression analysis revealed that both the complexity of the operation and the team size significantly affected PT. When procedure complexity and patient condition were kept constant, adding one team member in our data analysis predicted an increase of 34.7 min in the PT. Conclusion The surgical team size has a measurable effect on PT. Aside from surgical complexity, the team composition and member stability affected PT in the OR. Optimizing surgical teams and developing a strategy to maintain team stability are of great importance for improving OR efficiency.

Surgical Endoscopy, 2012

Background In preparing for the fundamentals of laparoscopic surgery (FLS) exam, residents usuall... more Background In preparing for the fundamentals of laparoscopic surgery (FLS) exam, residents usually adopt a self-learning strategy where practice time can be managed with more flexibility. However, with this self-learning strategy, there is a lack of direct supervision from experts and residents risk understudying for this high-stakes exam. Our objective is to determine study goals for effective selfguided practice for the FLS manual skills tasks that will result in passing the examination. Methods FLS manual skills data for all PGY-5 residents during 2009-2010 was supplied by the FLS administrative office. Descriptive statistics were performed, and data were regrouped by the pass/fail results of the exam. The minimum practice time requirement for passing each manual skills task is reported in order to guide practice. Results 1,047 proctored FLS exams were completed by 2009-2010 residents. Mean task time achieved by all residents was 84 ± 31 s for peg transfer, 139 ± 54 s for pattern cut, 78 ± 29 s for endoloop, 158 ± 66 s for extracorporeal suturing, and 168 ± 77 s for intracorporeal suturing. In the pass group (n = 988), mean time to complete each task was 80 s for peg transfer, 134 s for pattern cut, 75 s for endoloop, 148 s for extracorporeal suturing, and 160 s for intracorporeal suturing. Calculations suggest a self-study goal for each task of 53 s for peg transfer, 50 s for pattern cut, 87 s for endoloop, 99 s for extracorporeal suturing, and 96 s for intracorporeal suturing. If a resident can reliably achieve these results during self-study, they have an 84 % chance of passing the exam. Conclusions Residents preparing to take the FLS exam can refer to data presented in this study to set practice goals. Referring to these data-based practice goals will help residents to improve their chances of passing this highstakes exam.

Surgical Endoscopy, 2009

Background This video-aided observational study was conducted to examine team cooperation among s... more Background This video-aided observational study was conducted to examine team cooperation among surgeons in a surgical team built up with different time lengths. We predicted that the surgeons in a team that has longer teamwork experience would perform more anticipatory movements than surgeons in a surgical team that is newly formed. Methods Laparoscopic Nissen fundoplication cases were videotaped with both surgical view and the OR view. An anticipatory movement was identified when a surgeon manually provided direct assistance for an upcoming task without a request by other surgeons in the team. Result A total of 28 cases of laparoscopic Nissen fundoplication were videotaped and analyzed. Fifteen operations were performed by surgeons collaborating as a team for 10 weeks, in contrast to 13 operations performed by surgeons paired up for less than 5 weeks. Significantly more anticipatory movements were performed by the surgeons in the dedicated team (22 counts) than by those in the developing team (19 counts, p = 0.029). However, the OR time was not significantly different (dedicated team = 111 min, developing team = 115 min, p = 0.611) between the two teams which suggests that other types of coordination would also influence surgical teamwork. Conclusion Working in a team allows surgeons to develop sophisticated cognition to anticipate an upcoming task and provide assistance without verbal communication. The greater number of anticipatory movements observed in the dedicated surgical team suggests that anticipatory movement can be a valuable measure for team cooperation. Further research with a larger number of cases is needed to see whether performance of more anticipatory movements does shorten OR time.