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Summary All-optical physiology (AOP) manipulates and reports neuronal activities with light, allowing for interrogation of neuronal functional connections with high spatiotemporal resolution. However, contemporary high-speed AOP platforms are limited to single-depth or discrete multi-plane recordings that are not suitable for studying functional connections among densely packed small neurons, such as neurons in Drosophila brains. Here, we constructed a 3D AOP platform by incorporating single-photon point stimulation and two-photon high-speed volumetric recordings with a tunable acoustic gradient-index (TAG) lens. We demonstrated the platform effectiveness by studying the anterior visual pathway (AVP) of Drosophila. We achieved functional observation of spatiotemporal coding and the strengths of calcium-sensitive connections between anterior optic tubercle (AOTU) sub-compartments and >70 tightly assembled 2-μm bulb (BU) microglomeruli in 3D coordinates with a single trial. Our work aids the establishment of in vivo 3D functional connectomes in neuron-dense brain areas., Graphical Abstract, Highlights • All-optical volumetric physiology = precise stimulation + fast volumetric recording • Precise single-photon point stimulation among genetically defined neurons • 3D two-photon imaging by an acoustic gradient-index lens for dense neural structures • Observation of 3D functional connectivity in Drosophila anterior visual pathway, Neuroscience; Techniques in Neuroscience; Biological Sciences Research Methodologies; Biological Sciences Tools

A new coordination polymer {[Co2(DPDBT)2(DCPS)2(H2O)](H2O)} n (1) [DPDBT = 2,8-di(pyridin-4-yl)dibenzothiophene, H2DCPS = 4,4′-dicarboxydiphenyl sulfone], was synthesized under solvothermal conditions. Complex 1 exhibits a 2D structure with two different kinds of binuclear cobalt cluster units. The UV/Vis spectra of 1 and of the ligands were investigated, indicating that complex 1 is a potential wide gap semiconductor material.

Maintenance cycle optimization of power generation equipments is a complex decision-making process which needs to consider risk, availability and cost .This paper uses Probabilistic risk assessment (PRA) technology in maintenance cycle optimization, establishes multi-component maintenance risk-cost model,conducts comprehensive optimization best cycle and the lowest cost. Introduce PSO method as optimized decisions, find the optimal maintenance cycle for the target of the lowest total maintenance costs and achieving the required level of safety, improve optimized speed and the quality of reconciliation.

In recent years, the techniques of super-resolution have generated widespread impacts in science. Stimulated emission depletion (STED) microscopy is known for achieving sub-diffraction-limit resolution by using a donut-shaped beam to deplete the fluorescence around a focal spot while leaving a central part active to emit fluorescence. However, since STED microscopy is based on fluorescence, it suffers from photo-bleaching. We recently developed a new technique and termed it as suppression of scattering imaging (SUSI) microscopy. It uses a STED-like setup and achieves super resolution imaging by utilizing the nonlinearity of scattering from gold nanoparticles. Therefore, SUSI microscopy avoids the photo-bleaching issue. Nonetheless, for fast volumetric imaging, SUSI microscopy is limited with slow axial translation of the objective or sample. Here we combine SUSI microscopy with a refractive-index-variable lens to axially move the focus at very high speed. This combination allows simultaneous observation of tissue dynamics over a three-dimensional volume within one second. The new technique paves the way toward high-speed super-resolution imaging for biological tissues.

New designs of obtaining dual-band circular polarization (CP) radiation of a single-feed square microstrip antenna are proposed and experimentally studied. The proposed single-feed dual-band CP designs are achieved by inserting four T-shaped slits at the patch edges or four Y-shaped slits at the patch corners of a square microstrip antenna. From experiments conducted, a patch size reduction as large as 36% for the proposed design, compared to a conventional CP design without the inserted slits, has been obtained. Details of the design considerations of the proposed antennas are described, and experimental results of the obtained dual-band CP performances are presented and discussed.

A novel compact circular polarization (CP) design of a single-feed equilateral-triangular microstrip antenna with a Y-shaped slot is presented. The Y-shaped slot is cut in the patch with its upper two arms facing either the triangle tip or the bottom side of the triangular patch. Results show that, with a proper size of the Y-shaped slot, the present proposed design can have an antenna size reduction up to about 19% for operating at a given frequency for circular polarization, as compared to the regular-size circularly polarized triangular microstrip antenna. The proposed antenna design is described and studied. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 31–34, 1999.

The major area of current interest in adaptive arrays in their application to problems arising in radar, sonar, and communication systems, where the designer almost invariably faces the problem of interference suppression. In general, for real time processing, the robustness, with respect to the changed environment, of the adaptive beamforming algorithm with rapid convergence rate is desired. In this paper, a new hybrid adaptive beamforming algorithm is derived in the discrete‐cosine transformed domain for multiple jammers suppression. Overall performance improvement, in terms of convergence rate and the computational requirement, is addressed. From computer simulation results, it was found that the presented method outperformed the conventional Frost’s linear constraints LMS algorithm, in terms of the capability of jammers suppression and the rate of convergence.

This study focuses on how to design teaching materials for learning disabled students. User-friendly and user-centred interface design are the basic rules. In this study, we understand different needs from different learning disabled students, then design and made customer-made teaching materials, it is discussed to explicate why the design worked well and how it can be improved on different case study. This study applies touch screen and single switch as assistive technology the use for learning disabled students. It is improve the interactivity of teaching aid for students. There are four teachers work for disabled students take part in this study. The design of the teaching materials offered both the teachers and students a novel learning method.

The present article proposes two promising compact dual-frequency antenna designs with four narrow slots or four T-shaped slots. The proposed designs have been successfully implemented. The two operating frequencies can easily be controlled by the aspect ratio of the rectangular patch and the slot size embedded in the patch. Results also indicate that the two proposed designs can have a larger antenna size reduction for a fixed dual-frequency operation than the compact dual-frequency designs shown in Wong and Yang (1997, 1998).

The characteristics of a slot-coupled small triangular microstrip antenna with a shorting-pin or chip-resistor loading have been studied. Both the shorted and chip-resistor-loaded patch antennas show a significant reduction in the antenna size, as compared with the regular patch antenna, at a fixed operating frequency. The chip-resistor-loaded patch antenna also has a much broader operating bandwidth, as compared to the regular patch or shorted patch antennas. Furthermore, the related designs applied to the rectangular and circular microstrip antennas have also been implemented.

Insulin-like growth factors (IGFs) are potent mitogenic and differentiation-promoting factors that regulate the growth and development of many fetal tissues. Their role in the development of the adrenal gland and activation of its function is not known. The latter is crucial in providing the stimulus for the maturation of various fetal organs and determines the onset of parturition in sheep. To examine the hypothesis that IGFs are important autocrine/paracrine regulators of fetal adrenal development in vivo, we localized IGF-I and IGF-II mRNAs and peptides in the adrenal glands of developing sheep fetuses and correlated the cellular distribution with localization of 3 beta-hydroxysteroid dehydrogenase, tyrosine hydroxylase, and phenylethanolamine-N-methyltransferase enzymes by immunohistochemistry. Adrenal glands from 60- to 75-day-old (n = 4), 100- to 110-day-old (n = 4), 120- to 130-day-old (n = 4), and 145- to 147-day-old (term; n = 4) fetal sheep and 1- to 4-day-old newborn lambs (n = 4) were dissected and either snap-frozen or fixed. Total RNAs were subjected to Northern analysis using ovine IGF-I and IGF-II cDNA probes. Seven IGF-II transcripts of 1.2-6.0 kilobases (kb) were identified in the adrenal glands of fetuses at all gestational ages, and in the newborn. By densitometry, the abundance of IGF-II mRNA was highest in the fetal adrenal gland at 60 days, decreased slightly between 60 and 100 days, remained relatively constant until term, and decreased significantly after birth. At all gestational ages, IGF-II mRNA was detectable in significantly greater abundance than IGF-I mRNA. IGF-I and IGF-II mRNAs were localized by in situ hybridization using 35S-labeled anti-sense cRNA probes, and the peptides by immunohistochemistry using specific antisera. Low levels of IGF-I mRNA were detected in the zona fasciculata, but not in the zona glomerulosa. There was strong hybridization of the IGF-II cRNA to the zona glomerulosa and fasciculata and to the capsule. The hybridization signal was greater in the zona fasciculata than in the zona glomerulosa. IGF-II mRNA was also detected in groups of cells within the medulla. Localization of IGF-II mRNA by in situ hybridization correlated well with the distribution of IGF-II immunoreactivity and with 3 beta-hydroxysteroid dehydrogenase-positive cells in the cortex and in groups of cells within the medulla.(ABSTRACT TRUNCATED AT 400 WORDS)

The design of a modified planar inverted F antenna (PIFA) which is more compact (antenna length

A design using an inclined-slot-coupling feed for dual-frequency operation of a rectangular microstrip antenna with a cross-slot is described. Results show that, for a given dual-frequency operation, a reduction in antenna size of /spl sim/40% can be achieved by using this design. Also, the frequency ratio of the two frequencies is very slightly affected by the cross-slot length, and mainly determined by the aspect ratio of the patch, making the design simpler and easier to implement.

A new design of single-feed, reduced-size dual-frequency rectangular microstrip antenna with a cross slot of equal length is presented. The frequency ratio of the two operating frequencies is mainly determined by the aspect ratio of the rectangular patch, and the reduction in the two operating frequencies is achieved by cutting a cross slot in the microstrip patch. Details of the experimental results for such a design are presented and discussed.