385 research outputs found

    Electrochemical impedimetric biosensor based on a nanostructured polycarbonate substrate

    Get PDF
    This study integrates the techniques of nanoelectroforming, hot-embossing, and electrochemical deposition to develop a disposable, low-cost, and high sensitivity nanostructure biosensor. A modified anodic aluminum oxide barrier-layer surface was used as the template for thin nickel film deposition. After etching the anodic aluminum oxide template off, a three-dimensional mold of the concave nanostructure array was created. The fabricated three-dimensional nickel mold was further used for replica molding of a nanostructure polycarbonate substrate by hot-embossing. A thin gold film was then sputtered onto the polycarbonate substrate to form the electrode, followed by deposition of an orderly and uniform gold nanoparticle layer on the three-dimensional gold electrode using electrochemical deposition. Finally, silver nanoparticles were deposited on the uniformly deposited gold nanoparticles to enhance the conductivity of the sensor. Electrochemical impedance spectroscopy analysis was then used to detect the concentration of the target element. The sensitivity of the proposed scheme on the detection of the dust mite antigen, Der p2, reached 0.1 pg/mL

    Development of a Piezoelectric Vacuum Sensing Component for a Wide Pressure Range

    Get PDF
    In this study, we develop a clamped-clamped beam-type piezoelectric vacuum pressure sensing element. The clamped-clamped piezoelectric beam is composed of a PZT layer and a copper substrate. A pair of electrodes is set near each end. An input voltage is applied to a pair of electrodes to vibrate the piezoelectric beam, and the output voltage is measured at the other pair. Because the viscous forces on the piezoelectric beam vary at different air pressures, the vibration of the beam depends on the vacuum pressure. The developed pressure sensor can sense a wide range of pressure, from 6.5 × 10(-6) to 760 Torr. The experimental results showed that the output voltage is inversely proportional to the gas damping ratio, and thus, the vacuum pressure was estimated from the output voltage

    Trogodišnji trend promjena tjelesne pripremljenosti i indeksa tjelesne mase u učenika u dobi od 12 do 16 godina s ekstremnim indeksima tjelesne mase

    Get PDF
    The aim of this study was to investigate a three-year development in BMI and physical fitness of schoolchildren aged 12-16 years with extreme weight status. Taiwan Physical Fitness Test Battery, assessing aerobic fitness (1600-meter walk/run test), power (standing long jump), muscular endurance (sit-up), and flexibility (sit-and-reach) in 16,945 boys, was implemented in September from the year 2006 till 2008. Overweight and underweight were defined by the baseline BMI data values that fall within the highest and lowest 5% of their age population, whereas the BMI data values that fall within one standard deviation of the mean was considered “normal” in this study. The results showed that BMI of schoolchildren in 2006 was ~2–3 kg/m2 above the national average reported in 1993. All physical fitness components in the overweight group were substantially poorer than those in the normal group. Yet, these fitness parameters were improved over the three years in all groups. BMI in the underweight group increased at a faster rate than that in the normal and overweight groups. No difference was found in the jumping distance between the underweight and normal groups. Aerobic fitness in the underweight group was superior but flexibility and muscular endurance were slightly lower than those in the normal group. BMI of Taiwan schoolchildren increased substantially from 1993 to 2006 but leveled off from 2006 to 2008. Underweight schoolchildren during the growing period should not a priori be considered as physically weaker or unfit individuals.Cilj je ovog istraživanja bio ustanoviti trogodišnji trend razvoja indeksa tjelesne mase (ITM) i tjelesne pripremljenosti u učenika, u dobi između 12 i 16 godina, s ekstremnim vrijednostima tjelesne težine. Tajvanski sklop testova za tjelesnu pripremljenosti (Taiwan Physical Fitness Test Battery), koja uključuje procjenu aerobne pripremljenosti (test hodanja/ trčanja na 1600 metara), eksplozivne snage (skok u dalj s mjesta), mišićne izdržljivosti (podizanje trupa iz ležanja na leđima) i fleksibilnosti (sjed-i-dohvat), primijenjen je od 2006 do 2008 godine u mjesecu rujnu na uzorku od 16.945 dječaka. Preteški (overweight) i prelagani (underweight) ispitanici bili su definirani prema inicijalnoj vrijednosti ITM-a za dobnu skupinu populacije ispitanika kao oni koji se ubrajaju među 5% s najvišim odnosno najnižim vrijednostima ITM. Ispitanici koji su se nalazili unutar jedne standardne devijacije smatrali su se „normalnima“. Rezultati su pokazali da je ITM tajvanskih učenika u 2006. godini bio za ~2–3kg/m2 veći od nacionalnog prosjeka objavljenog 1993. godine. Sve varijable tjelesne pripremljenosti u grupi prekomjerno teških bile su značajno lošije u odnosu na rezultate koje su postigli ispitanici u normalnoj grupi. Ipak, rezultati su se u svim mjerenim varijablama u svim grupama poboljšali tijekom 3 godine mjerenja. ITM je u grupi nedovoljno teških porastao većom brzinom nego u grupama normalnih i prekomjerno teških učenika. Nije utvrđena značajna razlika u rezultatima skoka u dalj s mjesta između grupa nedovoljno teških i normalnih ispitanika. Nedovoljno teški ispitanici imali su najbolje rezultate u aerobnoj izdržljivosti u odnosu na ostale grupe, dok su u fleksibilnosti i mišićnoj izdržljivosti bili nešto slabiji nego ispitanici u normalnoj grupi. ITM je u tajvanske djece značajno porastao u razdoblju od 1993. do 2006. godine, ali je i stagnirao u razdoblju od 2006. do 2008. godine. Nedovoljno teška djeca ne bi se smjela a priori smatrati fizički slabijom ili nespremnom tijekom perioda odrastanja

    Konsep Demokrasi Politik Dalam Islam

    Full text link
    Coexistence of chronic rhinosinusitis (CRS) with asthma appears to impair asthma control. Type-2 innate lymphoid cells (ILC2s) respond to the cytokines of thymic stromal lymphopoietin (TSLP), interleukin (IL)-25 and IL-33, thus contributing to airway diseases such as CRS and asthma. We investigate whether the augmented Th2-cytokines in CRS might be related to sinonasal tract ILC2s corresponding to enhanced IL-25, IL-33 and TSLP release in severe asthmatics, and be involved in asthma control. Twenty-eight asthmatics (12 non-severe and 16 severe) with CRS receiving nasal surgery were enrolled. The predicted FEV1 inversely associated with CRS severity of CT or endoscopy scores. Higher expression of Th2-driven cytokines (IL-4, IL-5, IL-9, and IL-13), TSLP, IL-25 and IL-33 in nasal tissues was observed in severe asthma. Severe asthmatics had higher ILC2 cell counts in their nasal tissues. ILC2 counts were positively correlated with Th2-cytokines. Nasal surgery significantly improved asthma control and lung function decline in severe asthma and CRS. The higher expression of IL-33/ILC2 axis-directed type 2 immune responses in nasal tissue of CRS brought the greater decline of lung function in severe asthma. ILC2-induced the upregulated activity of Th2-related cytokines in asthmatics with CRS may contribute to a recalcitrant status of asthma control

    Effects of corner frequency on bandwidth and resonance amplitude in designing

    Get PDF
    ABSTRACT In the last decade, Lead Zirconate Titanate Oxide (PZT) thin-film actuators have received increasing attention because of their high frequency bandwidth, large actuation strength, fast response, and small size. The PZT film thickness is usually less than several microns as opposed to hundreds of microns for bulk PZT patches that are commercially available. As a result, PZT thin-film actuators pose unique vibration issues that do not appear in actuators with bulk PZT. Two major issues affecting actuator performance are the frequency bandwidth and the resonance amplitude. As an electromechanical device, a PZT thin-film actuator's bandwidth and resonance amplitude depend not only on the lowest natural frequency ! " n of the actuator's mechanical structure but also on the corner frequency

    Poly[[aqua­(μ5-3,4,5,6-tetra­carb­oxy­cyclo­hexane-1,2-dicarboxyl­ato)strontium] monohydrate]

    Get PDF
    In the title compound, {[Sr(C12H10O12)(H2O)]·H2O}n, the SrII ion is coordinated by six O atoms of five symmetry-related 3,4,5,6-tetra­carb­oxy­cyclo­hexane-1,2-dicarboxyl­ate ligands and one water mol­ecule in a slightly distorted monocapped trigonal–prismatic environment. The ligands bridge the SrII ions, forming a two-dimensional structure. In the crystal, O—H⋯O hydrogen bonds further connect the structure into a three-dimensional network. The H atoms of two of the carboxyl groups were refined as half-occupancy
    corecore