Tiny Piezoelectric Multi-Layered Actuators with Application in a Compact Camera Module—Design, Fabrication, Assembling and Testing Issues

Piezoelectric actuators with multi-layer structures have largely gained attention from academic and industry experts. This is due to its distinctive advantages of fast response time, huge generative force and the inherent good planar electromechanical coupling factor, as well as other mechanical qualities. Typically, lead zirconate titanate (PZT) is one of the most represented piezoelectric ceramic materials that have been used for multi-layer piezoelectric actuators. Piezoelectric multi-layered actuators (PMLAs) were developed vigorously in the past decades due to the emergence of portable devices, such as smartphones with a highly compact camera module (CCM) and an image stabilizer (IS). This study reviewed the progress made in the field of PMLA applications, with a particular focus on the miniaturized dimensions and associated generated output force, speed and maximum output power requirement for various loads. Several commercial attempts, such as Helimorph, Lobster and the two-degrees-of-freedom ultrasonic motor (USM), were investigated. The proposed simple bimorph and multi-layer bimorph USMs experimentally showed thrust as high as 3.08 N and 2.57 N with good free speed and structural thicknesses of 0.7 and 0.6 mm, respectively. When compared with the other 14 reported linear USMs, they ranked as the top 1 and 2 in terms of the thrust-to-volume ratio. The proposed design shows great potential for cellphone camera module application, especially in moving sensor image stabilization. This study also provided outlooks for future developments for piezoelectric materials, configurations, fabrication and applications

The DOE Grand Challenge in Computational Accelerator Physics

Introduction Particle accelerators are playing an increasingly important role in basic and applied science. For example, many countries are now involved in efforts aimed at developing accelerator-driven technologies for transmutation of radioactive waste, disposal of plutonium, energy production, and production of tritium. Additionally, next-generation spallation neutron sources based on similar technology will play a major role in materials science and biological science research. Finally, other types of accelerators such as the Large Hadron Collider (LHC), the Next Linear Collider (NLC), and fourth-generation light sources will have a significant impact on basic and applied scientific research. For all of these projects, high-resolution modeling far beyond that which has ever been performed by the accelerator community is required to reduce cost and technological risk, and to improve accelerator efficiency, performance, and reliability. Indeed, such modeling is essential t

Asian Plantain (Plantago asiatica) Essential Oils Suppress 3- Hydroxy-3-Methylglutaryl-Co-Enzyme A Reductase Ex- pression

Asian plantain (Plantago asiatica) essential oil (PAEO) contains multiple bioactive compounds, but its potential effects on lipid metabolism have not been examined. PAEO was found to be mostly composed of oxygenated monoterpenes, with linalool as the major component (82·5 %, w/w), measured using GC -MS. Incubation of 0 -200 mg PAEO/ml with HepG2 cells for 24 h resulted in no significant toxicity. Incubation with 0·2 mg PAEO/ml altered the expression of LDL receptor (þ 83 %; P,0·05) and 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase (2 37 %; P, 0·05), as assessed using RT-PCR. LDL oxidation was markedly inhibited by PAEO treatment due to the prevalence of linalool compounds in PAEO. Oral administration of PAEO for 3 weeks in C57BL/6 mice significantly reduced plasma total cholesterol and TAG concentrations by 29 and 46 %, respectively. The mRNA (þ58 %; P, 0·05), but not protein, levels of the LDL receptor were significantly higher, whereas both mRNA and protein levels of HMG-CoA reductase were significantly lower (246 and 211 %, respectively; P,0·05) in the liver of PAEO-fed than of control mice. The mRNA levels of CYP7A1 were marginally reduced in HepG2 cells, but not in mouse liver after PAEO treatment. Thus, PAEO may have hypocholesterolaemic effects by altering the expression of HMG-CoA reductase. Reduced TAG and oxidised LDL may provide additional cardiovascular protective benefits. Plantago asiatica: Essential oils: Cholesterol: 3-Hydroxy-3-methyl-glutaryl-co-enzyme A reductase: Low-density lipoprotein-receptor: Triacylglycerols CHD is a major cause of death in developed societies 1 . Elevated LDL-cholesterol and TAG levels are both independent risk factors for CHD 2 -4 . In addition, the presence of oxidised LDL accelerates atherogenesis 5

Preliminary Study on Characteristics of Atmospheric Polycyclic Aromatic Hydrocarbons in a Mega-city

Air pollutants are an important environmental concern particularly for the mega-city which has various pollutant sources. As a preliminary study, we investigated the levels of criteria air pollutants (SO2, CO, NO2, O3, PM2.5, and PM10) and polycyclic aromatic hydrocarbons (PAHs) in Busan, Korea during April~November 2010. Among the 16 US-EPA priority PAHs, 13 PAHs excluding naphthalene, acenaphthylene, and acenaphthene were quantified. The levels of gaseous and particulate PAHs were 1.58~9.52 ng/m3 (mean: 4.77 ng/m3) and 0.98~5.21 ng/m3 (mean: 2.84 ng/m3), respectively. PAHs were positively correlated with SO2, NO2, and PM2.5, suggesting that they had common emission sources. According to a pollution rose diagram, PAHs and criteria air pollutants seemed to be influenced by major wind directions, but this effect was not so significant due to geographical characteristics. On the basis of this study, the spatial distribution of PAHs can be simulated with those of criteria air pollutants.clos

Non-Laboratory-Based Risk Prediction Tools for Undiagnosed Pre-Diabetes: A Systematic Review

Early detection of pre-diabetes (pre-DM) can prevent DM and related complications. This review examined studies on non-laboratory-based pre-DM risk prediction tools to identify important predictors and evaluate their performance. PubMed, Embase, MEDLINE, CINAHL were searched in February 2023. Studies that developed tools with: (1) pre-DM as a prediction outcome, (2) fasting/post-prandial blood glucose/HbA1c as outcome measures, and (3) non-laboratory predictors only were included. The studies’ quality was assessed using the CASP Clinical Prediction Rule Checklist. Data on pre-DM definitions, predictors, validation methods, performances of the tools were extracted for narrative synthesis. A total of 6398 titles were identified and screened. Twenty-four studies were included with satisfactory quality. Eight studies (33.3%) developed pre-DM risk tools and sixteen studies (66.7%) focused on pre-DM and DM risks. Age, family history of DM, diagnosed hypertension and obesity measured by BMI and/or WC were the most common non-laboratory predictors. Existing tools showed satisfactory internal discrimination (AUROC: 0.68–0.82), sensitivity (0.60–0.89), and specificity (0.50–0.74). Only twelve studies (50.0%) had validated their tools externally, with a variance in the external discrimination (AUROC: 0.31–0.79) and sensitivity (0.31–0.92). Most non-laboratory-based risk tools for pre-DM detection showed satisfactory performance in their study populations. The generalisability of these tools was unclear since most lacked external validation