A*STAR Joint Council Office

In this paper, we present an experimental investigation of a water pipeline leak detection system based on a low-cost, tiny-sized hydrophone sensor fabricated using the microelectromechanical system (MEMS) technologies. A 10 × 10 element arrayed MEMS hydrophone device with chip size of 3.5 × 3.5 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> was used in the experiment. The hydrophone device is packaged with a customized on-board preamplification circuit using an acoustic transparent material. The overall package size of the MEMS hydrophone is Φ1.2 × 2.5 cm. The packaged MEMS hydrophone achieves an acoustic sensitivity of -180 dB (re: 1 V/μPa), a bandwidth from 10 Hz to 8 kHz, and a noise resolution of around 60 dB (re: 1 μPa/√Hz) at 1 kHz. A section of ductile iron water pipeline with an internal diameter of 10 cm, wall thickness of 0.73 cm, and length of 30 m is constructed as the test bed for the water leak detection. Two different leak sizes with leak flow rates of about 30 and 180 L/min are designed along the pipe, which is pressurized at 3.2 bar. Analysis of the transient signals and spectrograms shows that the MEMS hydrophone can capture the key acoustic information of the water leak, i.e., identifying the leak and locating the leak position. The measurement results demonstrate the feasibility to construct an affordable, highly efficient, real-time, and permanent in-pipe pipeline health monitoring network based on the MEMS hydrophones due to their high performance, low cost, and tiny size.

There is an urgent need for industrial Internet of things (IoT) solutions to deploy a smart hydrophone sensor grid to monitor pipeline health and to provide an accurate prediction in the event of any leakage. One solution is to develop an IoT water leakage detection system consisting of an interface to capture acoustic signals from aluminum nitride (AlN)-based micro-machined infrasonic hydrophone sensors that are fed as inputs and predict an approximate leak location as a form of output. Micro-electro-mechanical systems (MEMS) are particularly useful for IoT applications with low power consumption and small device footprint. Data analytics including characterization, pre/post processing are applied to determine the leaks. In this work, we have developed the process flow and algorithm to detect pipe leakage occurrence and pinpoint the location accurately. Our approach can be implemented to detect leaks for different pipe lengths, diameters and materials.

INTRODUCTION: Asian patients may have more difficulty seeking help for their sexual problems because of a largely conservative culture. Residents from both obstetrics and gynecology (OBGYN) and family medicine (FM) departments are ideally placed to address sexual problems. AIM: This survey explored the experience of residents from OBGYN and FM in managing sexual problems and their views on training in sexual medicine (SM). METHOD: An anonymized questionnaire collecting data on trainee characteristics, exposure to male and female sexual problems, and training in SM was sent to all FM and OBGYN residents in Singapore. These residents had completed their medical registration with the Singapore Medical Council and were at various stages of specialty training in both FM and OBGYN residency programs in Singapore. MAIN OUTCOME MEASURE: Trainees' exposure to male and female sexual problems and their views on training in Sexual Medicine. RESULTS: The overall response from the survey was 63.5% (122/192)-54% (70/129) and 69% (52/75) of FM and OBGYN residents responded, respectively. 63% were female, with 22% being senior residents, and 55% attended Singaporean medical schools. About one quarter (30/122) of the respondents encountered patients with sexual problems at least monthly. Most would refer these patients directly to specialists, psychologists, and sex therapists. More than 80% of residents were not confident in managing sexual problems in either sex (89% for male problems; 83% for female problems). Among the recognized categories, only 30% felt confident to manage erectile dysfunction, 26% for vaginismus, while less than 10% felt confident to manage libido, arousal, or orgasm disorders. 95% of the residents agreed that SM should be part of both training curricula, with 70% and 25% suggesting at junior and senior residency, respectively. 93% of them were interested to obtain further knowledge and skills in SM through their core training curriculum and from seminars. CONCLUSIONS: This survey reported a significant number of residents in OBGYN and FM departments are regularly exposed to patients with sexual problems but lack the skills to manage them. OBGYN residents were more familiar with managing female sexual problems while FM residents tend to have more experience in male sexual problems. Almost universally, the residents in FM and OBGYN were very keen to acquire skills in SM, and the results support the incorporation of appropriate knowledge and skills into both national residency program curricula. Huang Z, Choong DS, Ganesan AP, et al. A Survey on the Experience of Singaporean Trainees in Obstetrics/Gynecology and Family Medicine of Sexual Problems and Views on Training in Sexual Medicine. J Sex Med 2019;8:107-113.

Abstract The need to reduce ship emissions and the increase in fuel oil prices has driven the interest in incorporating alternative energy solutions to traditional power systems in the maritime industry. In this paper, a hybrid energy system of liquified natural gas (LNG) and batteries for a tugboat is developed and studied. The flexibility of the load allocation is believed to reduce fuel consumption and emission as the tugboats with dynamic power profiles benefited from splitting the load among the multiple power sources. The hybrid system model is created in MATLAB/Simulink®. In addition, fuel data recorded from an operational diesel propulsion tugboat is used where the generated operational data are replicated in the Simulink model before any further analysis and comparisons are conducted. The LNG-hybrid system is tested in three different configurations without the battery in both fixed speed and variable speed, and with a battery. The daily fuel cost, CO2 emissions, energy efficiency operation indicator (EEOI) and CII ratings are then calculated for the different configurations in three different operation cases for comparison studies. The results demonstrate that an average reduction of CO2 by 64.7% and a lowering average of daily fuel cost by 67.5% for an LNG battery hybrid tugboat are achieved as compared to a diesel system.

There is an urgent need for industrial IoT solutions to deploy a smart hydrophone sensor grid to monitor pipeline health and to provide an accurate prediction in the event of any leakage. One solution is to develop an IoT water leakage detection system consisting of an interface to capture acoustic signals from aluminum nitride (AlN) based micro-machined infrasonic hydrophone sensors that are fed as inputs and predicts an approximate leak location as a form of output. MEMS (Microwww.videleaf.com electro-mechanical system) are particular useful for IOT applications with low power consumption and small device footprint. Data analytics including characterization, pre/post processing are applied to determine the leaks. In this work, we have developed the process flow and algorithm to detect pipe leakage occurrence and pinpoint the location accurately. Our approach can be implemented to detect leaks for different pipe lengths, diameters and materials.

Damage accumulation is widely accepted as the central dogma of ageing, and it has been a long-standing belief that tobacco smokers must experience a faster rate of ageing than non-smokers. It is therefore puzzling as to why proportional hazard model is a popular choice in longitudinal studies given that its assumption assumes a constant hazard with increasing time. If the rate of ageing is accelerated, the hazard gradient of smokers d(log(μ(x)))/dx obtained from frailty parametric fit has to be steeper than non-smokers. This study examines the relative derivative for mortality d(log(μ(x)))/dx of British doctors born 1900-1909, and obtained estimates indicate that the rate of ageing is similar between smokers and non-smokers. A brief theorem is also elaborated to present the difference in life-years gained from interventions and policies by life-detrimental risk exposure; e.g. smokers 0.8; non-smokers 5.3 mins/day. The controversial assumption made in the central dogma of ageing, heterogeneity axiom and the application of proportional hazard models are unveiled in this condensed parametric analyses.

Advancements in ultrasonic imaging sensors (UISs), such as improvements in cost-effectiveness, low power consumption, and suitability for challenging environments, have been useful for drone navigation. However, existing microelectromechanical systems (MEMS) transducer arrays suffer from limitations due to the non-uniform stress distribution of the thin-film layers, which changes the resonant frequency of devices. To address this, a novel sector slitted transducer design was proposed, which enhances the acoustic pressure output while maintaining mechanical stability and reduces the sensitivity of the resonant frequency to residual stresses. In this study, finite element analysis was used to model the slitted transducer design, which demonstrated minimal variation in resonant frequencies under different stress conditions. The MEMS transducer array simulations have displayed effective beam-steering capabilities using different phase profiles and validation of performance metrics through the Fresnel and Fraunhofer diffraction propagations. Both the imaging resolution and signal-to-noise ratio (SNR) of the array were evaluated over various distances. The figures-of-merit (FoM) of the sector-slitted design indicate that the transducer array is 1.6 to 30 times smaller than existing designs while being able to generate 26 to 965 times greater acoustic pressure than the other designs reported in the literature. Thus, the array promises enhanced performance in 3D range-finding and imaging applications for drones and mobile devices, offering compactness and efficiency. Future applications could leverage these advancements to improve autonomous navigation and environmental sensing in complex scenarios.

Background: LMNA-related Dilated Cardiomyopathy (LMNA-related DCM) is an aggressive type of DCM caused by pathogenic mutations in the LMNA gene that comprises 5-6% of genetic DCM cases. NVC-001 is an adeno-associated virus (serotype 9) gene-therapy vector encoding a truncated form of the naturally occurring human SUN1 protein (dnSUN1) that is being developed as a new treatment for LMNA-related DCM patients. Here we report the results of preclinical pharmacology, safety and biodistribution studies of NVC-001 that support a first-in-human clinical trial of NVC-001, which is a multicenter, non-randomized, open-label, ascending-dose Phase 1/2 study to assess the safety, tolerability and preliminary efficacy of NVC-001 in LMNA-related DCM patients. Methods: In vitro proof-of-concept studies were performed in human induced pluripotent stem cell (iPSC)-derived cardiomyocytes harboring the N195K pathogenic LMNA mutation. In vivo proof of concept studies were performed in a high-fidelity Lmna conditional deletion mouse model of LMNA DCM. Nonclinical biodistribution and safety of NVC-001 were assessed in both diseased and healthy mice, as well as in non-human primates. Results: NVC-001 successfully targeted the LINC complex in iPSC-derived human cardiomyocytes and rescued the arrhythmia phenotype of the N195K mutation. In the Lmna -deletion mouse model of LMNA DCM, NVC-001 treatment led to 8-fold longer survival in treated LMNA DCM mice (&gt;300 days) compared to untreated mice (&lt; 40 days), accompanied by halting of disease progression as indicated by stabilization of left ventricular function, rescue of conduction-system disease, and reduction in myocardial fibrosis. In biodistribution and safety studies in diseased and healthy mice and in cynomolgus monkeys, dnSUN1 transgene expression was restricted to the myocardium as intended with minimal to no expression in other tissues. No NVC-001-related clinical or histopathological adverse findings were observed at any dose level tested in diseased and healthy mice, or in cynomolgus monkeys. Conclusion: Collectively, these studies confirmed the transduction, target engagement and potential disease-modifying efficacy of NVC-001 in human target cells and in a LMNA DCM disease model. These data, together with the absence of adverse findings in multiple species, support investigation of NVC-001 in human LMNA-related DCM patients in a first-in-human adaptive-design Phase 1/2 clinical trial to be conducted in the US and in Europe.