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In this paper, we investigate the higher-order linear differential equations with meromorphic coefficients. We improve and extend a result of M.S. Liu and C.L. Yuan, by using the estimates for the logarithmic derivative of a transcendental meromorphic function due to Gundersen, and the extended Winman-Valiron theory which proved by J. Wang and H.X. Yi. In addition, we also consider the nonhomogeneous linear differential equations. [ABSTRACT FROM AUTHOR]

We investigated experimentally the spectra of MBSL in sodium chloride water solution with krypton as dissolved gas. We observed and compared the spectra of hydroxyl ion at 310 nm and that of sodium atom at 589 nm. It has been found that under the same experimental condition, the intensity of sodium atom spectra is obviously higher than that of the hydroxyl ion spectra, and is more sensitive to the experimental condition. The krypton content, the concentration of sodium chloride solution, and the driving sound pressure obviously affect the spectra intensity in certain range. [ABSTRACT FROM AUTHOR]

In the paper, we use the theory of normal family to study the problem on entire function that share a finite non-zero value with their derivatives and prove a uniqueness theorem which improve the result of J.P. Wang and H.X. Yi. [ABSTRACT FROM AUTHOR]

A very-low-cost wireless personal area network (WPAN) receiver implemented in 0.25-µm CMOS technology consumes 17mW of power and occupies an area of 0.66 mm². Simplicity in the physical layer, which still supports the 1-Mb/s requirement, allows for power savings in the receive front-end. A new coding scheme permits the integration of a high-pass filter to mitigate DC offset and 1/f noise. A linear front-end eliminates the external band-preselect filter. This die area is the smallest reported for Bluetooth-class front-ends. [ABSTRACT FROM AUTHOR]

A frequency-synthesis technique which extracts the Nth harmonic from an N-stage oscillator is presented. This technique enables significant power savings in the prescaler of a frequency synthesizer. The maximum achievable voltage swing from such an oscillator is estimated. To study this technique, a multiply-by-3 circuit with two 180°-coupled single-ended three-stage ring oscillators has been fabricated in 0.24-μm CMOS, designed to work in the 902-928-MHz ISM band (U.S. and Canada). It provides two outputs: one at the normal operating frequency of the oscillator and the other at three times that frequency. The circuit can work at voltages as low as 1.3 V, while consuming 210 μA of current. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study aimed to quantify total lymphatic fluid spaces of the inner ears volumetrically in the dog in order to find a correlation between the lymphatic volume of the inner ears and motion sickness susceptibility. METHODS: A total of 16 healthy adult Beagle dogs were used to delineate the lymphatic fluid spaces of inner ears by magnetic resonance imaging with a 3-dim ensio nal-c onstr uctiv e interference steady-state sequence. Manual segmentation was applied for 3-dimensional reconstruction and volumetric quantification of total lymphatic space. The susceptibility of Beagle dogs to motion sickness was judged by latency of vomiting during rotatory stimulus. RESULTS: The volume range of total fluid space in the vestibule and cochlea of Beagle dogs is 55.07 ± 6.2 mm3. There is no significant difference in the total lymphatic volume of bilateral inner ears between 2 different motion sickness susceptibility groups (i.e., sensitive group and insensitive group), but the difference of lymphatic volume in the cochlea and vestibule between bilateral inner ears in insensitive group is greater than that of sensitive group. Moreover, a significant positive correlation was found between bilateral inner ear difference in lymphatic volume and vomiting latency. CONCLUSION: Magnetic resonance imaging could be used as a method to evaluate the inner ear lymphatic fluid volume of Beagle dogs with different susceptibilities to motion sickness, through which we found that motion sickness susceptibility is related to the difference in lymphatic volume in the vestibule and cochlea between bilateral inner ears, and the larger the volume difference, the lower the susceptibility. [ABSTRACT FROM AUTHOR]

The isoprenoid pathway converts pyruvate to isoprene and related isoprenoid compounds in plants and some bacteria. Currently, this pathway is of great interest because of the critical role that isoprenoids play in basic cellular processes, as well as the industrial value of metabolites such as isoprene. Although the regulation of several pathway genes has been described, there is a paucity of information regarding system level regulation and control of the pathway. To address these limitations, we examined Bacillus subtilis grown under multiple conditions and determined the relationship between altered isoprene production and gene expression patterns. We found that with respect to the amount of isoprene produced, terpenoid genes fall into two distinct subsets with opposing correlations. The group whose expression levels positively correlated with isoprene production included dxs, which is responsible for the commitment step in the pathway, ispD, and two genes that participate in the mevalonate pathway, yhfS and pksG. The subset of terpenoid genes that inversely correlated with isoprene production included ispH, ispF, hepS, uppS, ispE, and dxr. A genome-wide partial least squares regression model was created to identify other genes or pathways that contribute to isoprene production. These analyses showed that a subset of 213 regulated genes was sufficient to create a predictive model of isoprene production under different conditions and showed correlations at the transcriptional level. We conclude that gene expression levels alone are sufficiently informative about the metabolic state of a cell that produces increased isoprene and can be used to build a model that accurately predicts production of this secondary metabolite across many simulated environmental conditions.

In this paper, the influence of the active layer nanomorphology on device performance for ternary PbSxSe1−x quantum dot-based solution-processed infrared photodetector is presented. Firstly, ternary PbSxSe1−x quantum dots (QDs) in various chemical composition were synthesized and the bandgap of the ternary PbSxSe1−x QDs can be controlled by the component ratio of S/(S + Se), and then field-effect transistor (FET) based photodetectors Au/PbS0.4Se0.6:P3HT/PMMA/Al, in which ternary PbS0.4Se0.6 QDs doped with poly(3-hexylthiophene) (P3HT) act as the active layer and poly(methyl methacrylate) (PMMA) as the dielectric layer, were presented. By changing the weight ratio of P3HT to PbS0.4Se0.6 QDs (K = MP3HT:MQDs) in dichlorobenzene solution, we found that the device with K = 2:1 shows optimal electrical property in dark; however, the device with K = 1:2 demonstrated optimal performance under illumination, showing a maximum responsivity and specific detectivity of 55.98 mA W−1 and 1.02 × 1010 Jones, respectively, at low VDS = −10 V and VG = 3 V under 980 nm laser with an illumination intensity of 0.1 mW cm−2. By measuring the atomic force microscopy phase images of PbS0.4Se0.6:P3HT films in different weight ratio K, our experimental data show that the active layer nanomorphology has a great influence on the device performance. Also, it provides an easy way to fabricate high performance solution-processed infrared photodetector. [ABSTRACT FROM AUTHOR]

Point-of-care nucleic acid detection is essential for diagnosis and food safety, especially in resource-limited areas. This study reports a g ravity-driven and r otation-controlled (GR) chip-coupled lateral flow-based assay (LFA) for point-of-care nucleic acid detection. The sample solution is added to the inlet of the GR chip and flows into the loop-medicated isothermal amplification (LAMP) chamber by the action of gravity. After the LAMP reaction, the GR chip is manually rotated to allow the amplified solution to flow into the LFA chamber for result readout. The GR chip integrates the LAMP reaction and LFA in a fully closed environment, avoiding the aerosol contamination problem. The GR chip's simple and ingenious structure simplifies the fabrication and reduces its cost, making it possible for point-of-care and even home self-testing. [Display omitted] • Liquid flow on the chip is driven by gravity and controlled by rotation. • Amplicon-formed aerosol contamination can be avoided. • The chip has simple structure and low cost. • The chip is promising for the point-of-care or home self-testing. [ABSTRACT FROM AUTHOR]