Lab-on-a-chip biophotonics: its application to assisted reproductive technologies

Lai, David,Smith, Gary D.,Takayama, Shuichi Wiley (John WileySons) 2012 Journal of biophotonics Vol.5 No.8

<P>With the benefits of automation, sensitivity and precision, microfluidics has enabled complex and otherwise tedious experiments. Lately, lab-on-a-chip (LOC) has proven to be a useful tool for enhancing non-invasive assisted reproductive technology (ART). Non-invasive gamete and embryo assessment has largely been through periodic morpohological assessment using optical microscopy and early LOC ART was the same. As we realize that morphological assessment is a poor indication of gamete or embryo health, more advanced biophotonics has emerged in LOC ART to assay for metabolites or gamete separation via optoelectrical tweezers. Off-chip, even more advanced biophotonics with broad spectrum analysis of metabolites and secretomes has been developed that show even higher accuracy to predicting reproductive potential. The integration of broad spectrum metabolite analysis into LOC ART is an exciting future that merges automation and sensitivity with the already highly accurate and strong predictive power of biophotonics.</P>

East Meets West: An Ancient Game Sheds New Light on US-Asian Strategic Relations

( David Lai ),( Gary W Hamby ) 한국국방연구원 2002 The Korean Journal of Defense Analysis Vol.14 No.1

It is widely shared that Pacific Asia is emerging as the powerhouse of the 21st century. This region has the enduring Sinic culture that holds profound philosophical, political, and strategic thoughts that set the nations in this region apart from the rest of the world community, especially the US-led West. The United States seeks to establish a strategic edge and productive relations with the nations in this region. For this foreign policy to bear fruit, the United States must, among other things, follow Sun Zi`s advice to learn more about Asian society. In one particular aspect, the United States will be better served to supplement its traditional Western approach, one that is under the influence of poker- and chess-like logic, with a wei qi-based Asian strategy of international relations. A little knowledge of the ancient board game wei qi will take US national leaders a long way in achieving the US foreign policy objectives. The game of wei qi is a significant part of many Asian cultures and greatly influences their geopolitical thinking and behavior. It bears striking resemblance to international relations and warfare. The wei qi-based strategy to international affairs follows clearly an Asian way that emphasizes the interplay of yin and yang. It also exemplifies the Chinese military classics to a remarkable extent. The wei qi concept is not available in Western military strategic thought and literature. It is, after all, a different game.

Use of graded responsibility and common entrustment considerations among United States emergency medicine residency programs

Jason Lai,Benjamin Holden Schnapp,David Simon Tillman,Mary Westergaard,Jamie Hess,Aaron Kraut 한국보건의료인국가시험원 2020 보건의료교육평가 Vol.17 No.-

Purpose: The Accreditation Council for Graduate Medical Education (ACGME) requires all residency programs to provide increasing autonomy as residents progress through training, known as graded responsibility. However, there is little guidance on how to implement graded responsibility in practice and a paucity of literature on how it is currently implemented in emergency medicine (EM). Wesought to determine how EM residency programs apply graded responsibility across a variety of activities and to identify which considerations are important in affording additional responsibilities to trainees. Methods: We conducted a cross-sectional study of EM residency programs using a 23-question survey that was distributed by email to162 ACGME-accredited EM program directors. Seven different domains of practice were queried. Results: We received 91 responses (56.2% response rate) to the survey. Among all domains of practice except for managing critically illmedical patients, the use of graded responsibility exceeded 50% of surveyed programs. When graded responsibility was applied,post-graduate year (PGY) level was ranked an “extremely important” or “very important” consideration between 80.9% and 100.0% ofthe time. Conclusion: The majority of EM residency programs are implementing graded responsibility within most domains of practice. Whendecisions are made surrounding graded responsibility, programs still rely heavily on the time-based model of PGY level to determineadvancement.

Development of a Child Detection System with Artifcial Intelligence Using Object Detection Method

S. N. David Chua,S. F. Lim,S. N. Lai,T. K. Chang 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.6

The issue of children dying due to vehicular heatstroke has raised signifcant concerns of public interest. The advancement of artifcial intelligence (AI) technology, particularly in image classifcation and object detection, could be applied to overcome the current faws of the vehicular occupant detection devices that often failed to serve as a triggering system to caretakers. In this paper, a technique for child detection with transfer learning is proposed. A real-time child detection system that consisted of a camera as an input medium, a classifer to detect the presence of a child and a triggering system in audio and visual forms was established. The modern convolutional object detector, SSD Mobilenet v1 was trained with Microsoft Common Objects in Context (MS COCO) dataset as a starting point of the training process. The model was then assessed and retrained to possess the ability to classify human into an adult or a child. The accuracy of the model was measured by counting the percentage of pixels labelled correctly per class. Based on the mean Average Precision (mAP), the detection system achieved an overall precision of 0.969 and the experimental results obtained showed a precision of 0.883, giving an error of less than ten percent.

United States vs. North Korea in No-Limit Poker: Alligator Blood or Dead Money?

( Wade R Smith ),( David Lai ) 한국국방연구원 2005 The Korean Journal of Defense Analysis Vol.17 No.2

"Listen, here`s the thing. If you can`t spot the sucker in your first halfhour at the table, then you are the sucker." This line from Mike McDermott, a high-stakes poker genius in the popular movie "Rounders," highlights the fact that when playing no-limit poker, knowing your opponents is much more important than the strength of the cards you are dealt. In many respects, U.S.-North Korea confrontation over the past fifty-some years resembles no-limit poker play. The problem is that many in the U.S. national political and defense circles do not see it; therefore allowing North Korea to take advantage of it and confront the superpower on an equal footing. The lens of no-limit poker provides an attractive and easily understood tool for analysis and explanation of the historical U.S.-North Korean confrontation. However, it does not provide a useful means for solving the confrontation. The United States must recognize the deficiency of the no-limit poker lens and find a more productive method for dealing with North Korea.

Developmental competence of porcine parthenogenetic embryos relative to embryonic chromosomal abnormalities

Hao, Yan-Hong,Lai, Liang-Xue,Liu, Zhong-Hua,Im, Gi-Sun,Wax, David,Samuel, Melissa,Murphy, Clifton N.,Sutovsky, Peter,Prather, Randall S. Wiley Subscription Services, Inc., A Wiley Company 2006 Molecular reproduction and development Vol.73 No.1

<P>Parthenogenetically activated (PA) embryos exhibit delayed development, a lower blastocyst rate, and less successful development in vitro compared to in vitro fertilized (IVF) embryos. To investigate the possible mechanisms for unsuccessful parthenogenetic development, this study analyzed the chromosome abnormalities and developmental potential of porcine PA embryos. Mature oocytes were electrically activated and cultured in Porcine Zygote Medium-3 (PZM<SUB>3</SUB>) supplemented with 3 mg/ml BSA for 6, 7, or 8 days. The percentage of PA blastocysts was lower than that of IVF embryos on days 6 and 7 (16.4 ± 7.4 vs. 28.7 ± 3.7; 10.9 ± 2.8 vs. 21.5 ± 4.7, P < 0.05; respectively), and the PA blastocysts had significantly fewer nuclei than IVF blastocysts (23.2 ± 1.8 vs. 29.7 ± 0.8; 29.7 ± 3.3 vs. 32.0 ± 2.4, P < 0.05). The percentage of abnormal PA embryos (including embryos with condensed nuclei, arrested embryos and fragmented embryos) was higher than that of IVF embryos (PA: 52.9 ± 12.8 vs. 16.4 ± 7.4 on day 6), and increased with culture time (71.9 ± 12.1 vs. 10.9 ± 2.8. on day 7,and 75.0 ± 22.6 vs. 12.1 ± 2.3 on day 8, P < 0.05). The Day-6 PA blastocysts (n = 147) were divided into three classes according to the total number of nuclei (<20, 20–39, >40) and into three groups according to the morphological diameter (<150, 150–180, >180 µm). Of the haploid blastocysts, 56.1% had less than 20 nuclei, and 71.5% were less than 150 µm in diameter. Of all (114) blastocysts suitable for analysis, 55.5% displayed chromosomal abnormalities. Among chromosomal abnormalities in PA blastocysts, haploid blastocysts were most prevalent (43.6%), while polyploidy (4.4%) and mixoploidy (7.7%) embryos were less prevalent. Chromosomal abnormalities of porcine PA embryos might contribute to a higher rate of abnormal embryonic development. We suggest that a careful consideration should be given when using the blastocysts with smaller size, and establishing the optimum culture condition for PA embryos development in vitro. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc.</P>

Nucleation and Aggregative Growth of Palladium Nanoparticles on Carbon Electrodes: Experiment and Kinetic Model

Kim, Yang-Rae,Lai, Stanley C. S.,McKelvey, Kim,Zhang, Guohui,Perry, David,Miller, Thomas S.,Unwin, Patrick R. American Chemical Society 2015 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.119 No.30

<P>The mechanism and kinetics of the electrochemical nucleation and growth of palladium (Pd) nanoparticles (NPs) on carbon electrodes have been investigated using a microscale meniscus cell on both highly oriented pyrolytic graphite (HOPG) and a carbon-coated transmission electron microscopy (TEM) grid. Using a microscale meniscus cell, it is possible to monitor the initial stage of electrodeposition electrochemically, while the ability to measure directly on a TEM grid allows subsequent high-resolution microscopy characterization which provides detailed nanoscopic and kinetic information. TEM analysis clearly shows that Pd is electrodeposited in the form of NPs (approximately 1–2 nm diameter) that aggregate into extensive nanocrystal-type structures. This gives rise to a high NP density. This mechanism is shown to be consistent with double potential step chronoamperometry measurements on HOPG, where a forward step generates electrodeposited Pd and the reverse step oxidizes the surface of the electrodeposited Pd to Pd oxide. The charge passed in these transients can be used to estimate the amounts of NPs electrodeposited and their size. Good agreement is found between the electrochemically determined parameters and the microscopy measurements. A model for electrodeposition based on the nucleation of NPs that aggregate to form stable structures is proposed that is used to analyze data and extract kinetics. This simple model reveals considerable information on the NP nucleation rate, the importance of aggregation in the deposition process, and quantitative values for the aggregation rate.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2015/jpccck.2015.119.issue-30/acs.jpcc.5b03513/production/images/medium/jp-2015-03513y_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp5b03513'>ACS Electronic Supporting Info</A></P>

A comparison of 6 osteoporosis risk assessment tools among postmenopausal women in Kuala Lumpur, Malaysia

Li Shean Toh,Pauline Siew Mei Lai,David Bin-Chia Wu,Brian G. Bell,Cuu Phuong Linh Dang,Bee Yean Low,Kok Thong Wong,Giuseppe Guglielmi,Claire Anderson 대한골다공증학회 2019 Osteoporosis and Sarcopenia Vol.5 No.3

Objectives: To compare and assess the performance of 6 osteoporosis risk assessment tools for screening osteoporosis in Malaysian postmenopausal women. Methods: Six osteoporosis risk assessments tools (the Simple Calculated Osteoporosis Risk Estimation [SCORE], the Osteoporosis Risk Assessment Instrument, the Age Bulk One or Never Estrogen, the body weight, the Malaysian Osteoporosis Screening Tool, and the Osteoporosis Self-Assessment Tool for Asians) were used to screen postmenopausal women who had not been previously diagnosed with osteoporosis/osteopenia. These women also underwent a dual-energy X-ray absorptiometry (DXA) scan to confirm the absence or presence of osteoporosis. Results: A total of 164/224 participants were recruited (response rate, 73.2%), of which only 150/164 (91.5%) completed their DXA scan. Sixteen participants (10.7%) were found to have osteoporosis, whilst 65/150 (43.3%) were found to have osteopenia. Using precision-recall curves, the recall of the tools ranged from 0.50 to 1.00, whilst precision ranged from 0.04 to 0.14. The area under the curve (AUC) ranged from 0.027 to 0.161. The SCORE had the best balance between recall (1.00), precision (0.04e0.12), and AUC (0.072e0.161). Conclusions: We found that the SCORE had the best balance between recall, precision, and AUC among the 6 screening tools that were compared among Malaysian postmenopausal women.

Safety and efficacy of target controlled infusion administration of propofol and remifentanil for moderate sedation in non-hospital dental practice

Douglas Lobb,Masoud MiriMoghaddam,Don Macalister,David Chrisp,Graham Shaw,Hollis Lai 대한치과마취과학회 2023 Journal of Dental Anesthesia and Pain Medicine Vol.23 No.1

Background: Fearful and anxious patients who find dental treatment intolerable without sedative and analgesic support may benefit from moderate sedation. Target controlled infusion (TCI) pumps are superior to bolus injection in maintaining low plasma and effect-site concentration variability, resulting in stable, steady-state drug concentrations. We evaluated the safety and efficacy of moderate sedation with remifentanil and propofol using TCI pumps in non-hospital dental settings. Methods: A prospective chart review was conducted on 101 patients sedated with propofol and remifentanil using TCI pumps. The charts were completed at two oral surgeons and one general dentist's office over 6 months. Hypoxia, hypotension, bradycardia, and over-sedation were considered adverse events and were collected using Tracking and Reporting Outcomes of Procedural Sedation (TROOPS). Furthermore, patient recovery time, sedation length, drug dose, and patient satisfaction questionnaires were used to measure sedation effectiveness. Results: Of the 101 reviewed sedation charts, 54 were of men, and 47 were of women. The mean age of the patients was 40.5 ±18.7 years, and their mean BMI was 25.6 ± 4.4. The patients did not experience hypoxia, bradycardia, and hypotension during the 4694 min of sedation. The average minimum Mean Arterial Pressure (MAP) and heartbeats were 75.1 mmHg and 60.4 bpm, respectively. 98% of patients agreed that the sedation technique met their needs in reducing their anxiety, and 99% agreed that they were satisfied with the sedation 24 hours later. The average sedation time was 46.9 ± 55.6 min, and the average recovery time was 12.4 ± 4.4 min. Remifentanil and propofol had mean initial effect-site concentration doses of 0.96 µ/.ml and 1.0 ng/ml respectively. The overall total amount of drug administered was significantly higher in longer sedation procedures compared to shorter ones, while the infusion rate decreased as the procedural stimulus decreased. Conclusion: According to the results of this study, no patients experienced adverse events during sedation, and all patients were kept at a moderate sedation level for a wide range of sedation times and differing procedures. The results showed that TCI pumps are safe and effective for administering propofol and remifentanil for moderate sedation in dentistry.

Evaluation of the applicability of deep breathing test in the diagnosis of hypertension with white-coat effect in Chinese patients in primary care

Kam Sum Chan,Kit Ping Loretta Lai,Pang Fai Chan,Man Hei Matthew Luk,Vai Kiong David Chao 대한고혈압학회 2019 Clinical Hypertension Vol.25 No.2

Purpose: The current gold standard for the diagnosis of white-coat effect is by the 24-h ambulatory blood pressure monitoring (ABPM) which may not be readily available in every primary care setting. Previous studies had shown that deep breathing, through modulating the baroreceptor reflex sensitivity to vagal stimulation over 30 to 60 s, was useful in detection of the white-coat effect. The aim of our study was to evaluate the diagnostic accuracy of the deep breathing test (DBT) as compared with the gold standard of ABPM in the diagnosis of hypertension with white-coat effect in Chinese patients in primary care. Methods: This cross sectional study recruited 178 consecutive, eligible, consented, hypertensive patients receiving treatment at a local public primary care Hypertension Clinic. The diagnostic accuracy of the DBT in all recruited patients, patients not taking beta-adrenergic blockers and patients with different clinic SBP cut-off before the DBT by means of area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive and negative predictive values was evaluated. Results: The results for the ROC curves for systolic and diastolic BP changes after the DBT were statistically insignificant. The ROC curve was statistically significant for SBP change in patients not taking beta-adrenergic blockers and with pre-DBT clinic SBP ≥ 165 mmHg (ROC curve area of 0.719, 95% CI 0.53 to 0.91, p = 0.04). The corresponding sensitivity and specificity of the DBT were 40.9 and 90.9% respectively if SBP drop was > 30 mmHg. Conclusion: The DBT, even though could not be clinically applied to all patients, was proven to be a potential screening and diagnostic test for white-coat effect in Chinese hypertensive patients with a pre-test SBP of ≥165 mmHg and who were not taking beta-adrenergic blockers. Trial registration: This study was approved by Kowloon East Cluster/ Kowloon Central Cluster Research Ethics Committee/Institutional Review Board of Hospital Authority of Hong Kong under the registration KC/KE-16-0084/ER-3.