High Sensitivity,Wearable, Piezoresistive Pressure Sensors Based on Irregular Microhump Structures and Its Applications in Body Motion Sensing

A pressure sensor based on irregular microhump patterns has been proposed and developed. The devices show high sensitivity and broad operating pressure regime while comparing with regular micropattern devices. Finite element analysis (FEA) is utilized to confirm the sensing mechanism and predict the performance of the pressure sensor based on the microhump structures. Silicon carbide sandpaper is employed as the mold to develop polydimethylsiloxane (PDMS) microhump patterns with various sizes. The active layer of the piezoresistive pressure sensor is developed by spin coating PEDOT:PSS on top of the patterned PDMS. The devices show an averaged sensitivity as high as 851 kPa^?1, broad operating pressure range (20 kPa), low operating power (100 nW), and fast response speed (6.7 kHz). Owing to their flexible properties, the devices are applied to human body motion sensing and radial artery pulse. These flexible high sensitivity devices show great potential in the next generation of smart sensors for robotics, real‐time health monitoring, and biomedical applications.     

Enhanced analyte detection using in-source fragmentation of field asymmetric waveform ion mobility spectrometry-selected ions in combination with time-of-flight mass spectrometry

Miniaturized ultra high field asymmetric waveform ion mobility spectrometry (FAIMS) is used for the selective transmission of differential mobility-selected ions prior to in-source collision-induced dissociation (CID) and time-of-flight mass spectrometry (TOFMS) analysis. The FAIMS-in-source collision induced dissociation-TOFMS (FISCID-MS) method requires only minor modification of the ion source region of the mass spectrometer and is shown to significantly enhance analyte detection in complex mixtures. Improved mass measurement accuracy and simplified product ion mass spectra were observed following FAIMS preselection and subsequent in-source CID of ions derived from pharmaceutical excipients, sufficiently close in m/z (17.7 ppm mass difference) that they could not be resolved by TOFMS alone. The FISCID-MS approach is also demonstrated for the qualitative and quantitative analysis of mixtures of peptides with FAIMS used to filter out unrelated precursor ions thereby simplifying the resulting product ion mass spectra. Liquid chromatography combined with FISCID-MS was applied to the analysis of coeluting model peptides and tryptic peptides derived from human plasma proteins, allowing precursor ion selection and CID to yield product ion data suitable for peptide identification via database searching. The potential of FISCID-MS for the quantitative determination of a model peptide spiked into human plasma in the range of 0.45-9.0 μg/mL is demonstrated, showing good reproducibility (%RSD < 14.6%) and linearity (R(2) > 0.99).     

Turbine airfoil degradation in the persian gulf war

Helicopter turbine engines used in the Desert Shield and Desert Storm operations experienced excessive sand ingestion. Fine particles were able to bypass filters and proceed through the combustor or cooling gaspaths. The first-stage turbine vanes were impacted with viscous silicate particles, forming a deposit on the leading-edge root platform and resulting in overheating and oxidation. The chemistry of the raw sand determines that of the ingested powders, the deposits, and the material reactions.     

Recommending Personalized POIs from Location Based Social Network

Location based social networks (LBSNs) provide location specific data generated from smart phone into online social networks thus people can share their points of interest (POIs).POI collections are complex and can be influenced by various factors,such as user preferences,social relationships and geographical influence.Therefore,recommending new locations in LBSNs requires to take all these factors into consideration.However,one problem is how to determine optimal weights of influencing factors in an algorithm in which these factors are combined.The user similarity can be obtained from the user check-in data,or from the user friend information,or based on the different geographical influences on each user's check-in activities.In this paper,we propose an algorithm that calculates the user similarity based on check-in records and social relationships,using a proposed weighting function to adjust the weights of these two kinds of similarities based on the geographical distance between users.In addition,a non-parametric density estimation method is applied to predict the unique geographical influence on each user by getting the density probability plot of the distance between every pair of user's check-in locations.Experimental results,using foursquare datasets,have shown that comparisons between the proposed algorithm and the other five baseline recommendation algorithms in LBSNs demonstrate that our proposed algorithm is superior in accuracy and recall,furthermore solving the sparsity problem.     

应用于高温气体过滤的烧结金属过滤器

在应用于化学加工、石油炼制、石油化工和基础重工业生产的众多工业气体过滤的气固分离中,烧结金属过滤系统被证实是一种高效、可靠和经济的选择。叙述了工业应用的,特别是要求半固定过滤的在高温高压下腐蚀环境中应用的烧结金属粉末或者烧结金属纤维过滤器的优点,讨论了所选应用领域,包括流化催化裂化(FCC)和连续催化重整/脱硫(CCR)的过滤器的操作和性能。     

Increased disruption of sperm plasma membrane at sperm immobilization promotes dissociation of perinuclear theca from sperm chromatin after intracytoplasmic sperm injection in pigs

The effects of sperm-immobilization methods on decondensation of sperm chromatin and retention of subacrosomal sperm perinuclear theca (SAR-PT) after intracytoplasmic sperm injection (ICSI) were examined in pigs. Sperm membrane damage caused by different immobilization methods by rubbing with a micropipette without piezo pulses (R), or with a low (L) or high (H) intensity of piezo pulses while rubbing, was assessed by the time required for staining of sperm heads with eosin Y solution. The average time for staining of sperm heads immobilized by the R, L or H treatments was 76, 41 or 26 s, respectively. The fertilization rate following ICSI was increased by sperm immobilization by piezo pulses compared with R, but increased intensity of pulses from L to H did not cause further improvements (29, 48 and 47%, respectively). An immunofluorescence study revealed that H immobilization promoted the dissociation of SAR-PT from sperm chromatin compared with L and R, and it increased the frequency of male pronuclear formation in which chromatin appeared uniformly decondensed. With in vitro fertilization (IVF), SAR-PT disassembled coordinately with sperm chromatin decondensation and it was not detectable around male pronuclei. This was different from most of the oocytes after ICSI in which remnants SAR-PT were detected adjacent to male pronuclei. We concluded that increased damage on the sperm plasma membrane at immobilization improved fertilization rates and decondensation of sperm chromatin after ICSI due to the accelerated dissociation of SAR-PT from the sperm nucleus. Also, the behavior of SAR-PT after ICSI was different from that observed in oocytes after IVF.     

Evaluation of layout and atmospheric stability effects in wind farms using large‐eddy simulation

Large‐eddy simulation (LES) has been used previously to study the effect of either configuration or atmospheric stability on the power generated by large wind farms. This is the first study to consider both stability and wind farm configuration simultaneously and methodically with LES. Two prevailing wind directions, two layouts (turbines aligned versus staggered with respect to the wind) and three stabilities (neutral and moderately unstable and stable) were evaluated. Compared with neutral conditions, unstable conditions led to reduced wake losses in one configuration, to enhanced wake losses in two and to unchanged wake losses in one configuration. Conversely, stable conditions led to increased wake losses in one, decreased wake losses in two and unchanged wake losses in one configuration. Three competing effects, namely, rates of wake recovery due to vertical mixing, horizontal spread of wakes and localized regions of acceleration caused by multiple upstream wakes, were identified as being responsible for the observed trends in wake losses. The detailed flow features responsible for these non‐linear interactions could only be resolved by the LES. Existing analytical models ignore stability and non‐linear configuration effects, which therefore need to be incorporated. Copyright © 2017 John Wiley & Sons, Ltd.     

Subject Choice and Occupational Aspirations among Pupils at Girls' Schools

Various studies have found that British girls' curriculum subject preferences and future aspirations have changed and diversified in recent years. Other work has suggested that girls educated in single-sex schools might have a different (perhaps less gender-stereotypical) experience of education in comparison with their contemporaries at co-educational schools. This article draws on a study of the preferences of girls in English single-sex schools to explore these issues of subject choice and occupational aspiration further. It is argued that, like girls in mixed-sex secondary schools, single-sex schoolgirls' subject preferences have become more diverse and less gender-stereotypical than was the case twenty years ago. But where single-sex schoolgirls might have been expected to rate maths and science more highly than their counterparts in mixed-sex schools, the reverse was the case. Our findings support the argument that girls are now significantly more academically focused and ambitious for their future occupations than they were twenty years ago. However, we argue that a gender dichotomy remains evident in the types of future occupation chosen by girls.