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Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) are two common diseases that affect the elderly population worldwide. The identification of common genes associated with AD and T2DM holds promise for potential biomarkers and intriguing pathogenesis of these two complicated diseases. This study utilized a comprehensive approach by integrating transcriptome data from multiple cohorts, encompassing both AD and T2DM. The analysis incorporated various data types, including blood and tissue samples as well as single-cell datasets, allowing for a detailed assessment of gene expression patterns. From the brain region-specific single-cell analysis, PIP4K2A, which encodes phosphatidylinositol-5-phosphate 4-kinase type 2 alpha, was found to be expressed mainly in oligodendrocytes compared to other cell types. Elevated levels of PIP4K2A in AD and T2DM patients' blood were found to be associated with key cellular processes such as vesicle-mediated transport, negative regulation of autophagosome assembly, and cytosolic transport. The identification of PIP4K2A's potential roles in the cellular processes of AD and T2DM offers valuable insights into the development of biomarkers for diagnosis and therapy, especially in the complication of these two diseases. [ABSTRACT FROM AUTHOR]

The catalyst‐controlled diversity‐oriented synthesis of spirohydroquinoline‐indandiones and 3‐methylenehydroquinoline‐indandiones from ortho‐sulfonamidophenyl‐substituted para‐quinone methides and allylidene‐indandiones is reported. The strategies utilized an organobase such as DMAP or TMG to control the reaction pathway chemoselectively, furnishing the corresponding products in 40–99% yields with excellent diastereoselectivities. The mechanistic studies revealed that spirohydroquinoline‐indandione was the kinetic product to afford 3‐methylenehydroquinoline‐indandione in the presence of TMG, which probably involved an unusual base‐initiated 1,3‐nitrogen rearrangement process. [ABSTRACT FROM AUTHOR]

A novel coupling technique for circularly polarized square-ring patch antenna is developed and discussed. The circular polarization (CP) radiation of the square-ring patch antenna is achieved by a simple microstrip feed line through the coupling of a square patch on the same plane of the antenna. Proper positioning of the coupling square patch excites two orthogonal resonant modes with 90[degrees] phase difference, and a pure circular polarization is obtained. The dielectric material is a square block of ceramic with a permittivity of 58 and that reduces the size of the antenna. The prototype has been designed, fabricated and found to have an impedance bandwidth of 1.1% and a 3-dB axial-ratio bandwidth of about 0.03 % at GPS frequency of 1573 MHz. The characteristics of the proposed antenna have been studied by simulation software HFSS and experiments. The measured and simulated results are in good agreement. Index Terms--Ceramic dielectric material, circular polarization (CP), global position system (GPS), square-ring patch antenna.

A novel coupling technique for circularly polarized annular-ring patch antenna is developed and discussed. The circular polarization (CP) radiation of the annular-ring patch antenna is achieved by a simple microstrip feed line through the coupling of a fan-shaped patch on the same plane of the antenna. Proper positioning of the coupling fan-shaped patch excites two orthogonal resonant modes with 90[degrees] phase difference, and a pure circular polarization is obtained. The dielectric material is a cylindrical block of ceramic with a permittivity of 25 and that reduces the size of the antenna. The prototype has been designed and fabricated and found to have an impedance bandwidth of 2.3% and a 3 dB axial-ratio bandwidth of about 0.6% at the center frequency of 2700 MHz. The characteristics of the proposed antenna have been by simulation software HFSS and experiment. The measured and simulated results are in good agreement. Index Terms--Annular-ring patch antenna, ceramic dielectric material, circular polarization (CP), patch coupling.

This paper describes an ultrahigh frequency (UHF) tag antenna mounted on a metallic plate for radio frequency identification (RFID). The impedance of the proposed antenna can be tuned using various methods. The compact patch antenna consists of a C‐shaped resonator and a ground plane connected to a small shorting wall and is connected to a feeding loop in the middle of the C‐shaped resonator. Etching a couple of slits close to the shorting wall and a slot in the center of the C‐shaped resonator provided a flexible method for adjustment to match the conjugate impedance with the UCODE 8/8 m chip (13 − j191 Ω at 915 MHz). The optimal design with an overall size of 30 × 30 × 3 mm3 (0.092 λ0 × 0.092 λ0 × 0.0092 λ0) yielded a high power transmission coefficient of 91% and reading range of 6.4 m for the effective isotropic radiated power (EIRP) of 4.0 W when the tag antenna was mounted on a 220 × 220 mm2 metal plate. The proposed antenna was designed at standard frequency bands of the Federal Communications Commission (FCC, 902‐928 MHz) for North America and Taiwan. Antenna fabrication and testing were performed, which revealed that the measured data were in good agreement with the simulation results. [ABSTRACT FROM AUTHOR]

Flaccid paralysis in the upper extremity is a severe motor impairment after stroke, which exists for weeks, months, or even years. Electroacupuncture treatment is one of the most widely used TCM therapeutic interventions for poststroke flaccid paralysis. However, the response to electroacupuncture in different durations of flaccid stage poststroke as well as in the topological configuration of the cortical network remains unclear. The objectives of this study are to explore the disruption of the cortical network in patients in different durations of flaccid stage and observe dynamic network reorganization during and after electroacupuncture. Resting-state networks were constructed from 18 subjects with flaccid upper extremity by partial directed coherence (PDC) analysis of multichannel EEG. They were allocated to three groups according to time after flaccid paralysis: the short-duration group (those with flaccidity for less than two months), the medium-duration group (those with flaccidity between two months and six months), and the long-duration group (those with flaccidity over six months). Compared with short-duration flaccid subjects, weakened effective connectivity was presented in medium-duration and long-duration groups before electroacupuncture. The long-duration group has no response in the cortical network during electroacupuncture. The global network measures of EEG data (sPDC, mPDC, and N) indicated that there was no significant difference among the three groups. These results suggested that the network connectivity reduced and weakly responded to electroacupuncture in patients with flaccid paralysis for over six months. These findings may help us to modulate the formulation of electroacupuncture treatment according to different durations of the flaccid upper extremity. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to explore the association between socioeconomic status and urinary incontinence (UI). Methods: We used data from the three waves of the Taiwan Longitudinal Study on Aging. This study included 2458 women and 2866 men aged ≥50 years. We used logistic random effects models to examine the associations of interest, adjusting for demographics, health‐related behaviors, disability, number of health conditions and prostate problems for men and numbers of children for women. Results: In adjusted analysis, women with secondary education least frequently reported UI compared with women with no formal education (adjusted odds ratio [AOR] 0.41, 95% confidence interval [95% CI] 0.22–0.79). Those with severe economic hardships (vs those with no economic hardships) had an increased risk of UI among men and women (AOR 2.71, 95% CI 1.72–4.25 and AOR 1.94, 95% CI 1.31–2.88, respectively). Compared with men doing mentally demanding jobs, service workers/salesperson and retired men were more prone to UI (AOR 2.67, 95% CI 1.14–6.36 and AOR 2.41, 95% CI 1.19–4.87, respectively). Further analysis showed that the associations of economic hardship with UI were attenuated when adjusting for access to healthcare. Conclusion: No formal education in women and severe economic hardship in both the sexes were associated with an increased risk of UI among middle‐aged and older persons. The disparities should be taken into account in interventions for prevention, treatment and management of UI. Geriatr Gerontol Int 2021; 21: 245–253. [ABSTRACT FROM AUTHOR]

Background. In China, electroacupuncture based on meridians theory "treating flaccid paralysis by Yangming alone" has been widely used for stroke rehabilitation in clinical practice. The aim of this study was to explore the electroencephalography change of electroacupuncture intervention on strokes patients with flaccid paralysis. Methods. Twenty-three stroke patients with flaccid paralysis and six stroke patients with spasticity accepted electroacupuncture with the acupoints Hegu [LI4], Shousanli [LI10], and Quchi [LI11] for 20 minutes and their EEG data were recorded before, during, and after the electroacupuncture intervention. Results. Compared with the baseline EEG signals before electroacupuncture, the ipsilesional and contralesional beta-band average power of patients with flaccid paralysis and spasticity were significantly increased during the needles retention stage and decreased slightly after removing the needles. The significant decrease of the ipsilesional and contralesional delta band average power in patients with flaccid paralysis occurred during the electroacupuncture stimulation, and they increased after the removal of the needles. The ipsilesional delta band average power of patients with spasticity significantly decreased during the electroacupuncture stimulation. Conclusion. From this pilot electrophysiological study, we provided a possible electrophysiological mechanism of the curative effect of electroacupuncture for stroke rehabilitation. [ABSTRACT FROM AUTHOR]

In this study, multi‐band antenna for LTE wearable device with shared slots and radiators for smart watch was present. This study incorporated 4G communication frequency bands, a GPS positioning system, and BT/Wi‐Fi in a 43.6 × 43.6 × 5.8 mm3 metal case to achieve satisfactory radiation fields and performance efficiency within a small space. This article presents an overview of the theory. There are four ports in the system. Frist, Port 1 is a low‐frequency antenna offering LTE 700 and GSM 850/900. The maximal gain and efficiency are respectively 3.9 dBi and 82%. Second, Port 2 is a high‐frequency monopole with a winding long path on the side of the frame to achieve a reflection loss bandwidth that fully encompasses GSM 1800/1900/UMTS and LTE 2300/2500. The maximal gain and efficiency of this port are respectively 5.3 dBi and 92%. There are also have GPS (Port 3) and Wi‐Fi (Port 4) antenna implement IFA and loop excitation mechanisms, respectively. This antenna system can fulfill the market demand. As confirmed through both simulation and measurement, the antenna can cover LTE bands. Increasing the path capacity of a MIMO system to increase the transmission speed is a crucial focus in mobile communication research and development. [ABSTRACT FROM AUTHOR]

A dipole antenna with a bent dumbbell shape was positioned above and horizontal to a metal reflector to improve peak gain and steering of the radiation pattern. A parasitic square patch etched on the bottom side of the dumbbell arms provided a feeding delay line for producing dipole radiation in the 3600 MHz band. For gain enhancement and beam reconfiguration, the height of the horizontal dipole and the metal reflector could be adjusted to generate constructive reflections in phase with the radiated waves. When a dipole antenna with a height equal to half a wavelength was installed above the metal reflector, it exhibited a tilted main beam of 48° and maximum gain reached 9.2 dBi. A multiple-input–multiple-output antenna with a pair of strip stubs was also investigated. Simulation and measurement results indicated that the proposed structure achieved good isolation. The antenna had an impedance bandwidth (VSWR ≤ 2) of approximately 19.0% (3146–3818 MHz) and a low coupling (S21) of less than −25 dB. In this band, the average gain enhancement approximated 5.1 dBi. [ABSTRACT FROM AUTHOR]

A novel radio frequency identification tag antenna is composed of a resonant open-slot exciter and a dipole-type ground radiator. For a conjugate match to the Alien Higgs-4 chip impedance of 8−j149 Ω at 925 MHz, a quarter wavelength open-slot resonator embedded at the center of the dipole-type ground plane (130 × 18 mm2) was investigated and fabricated. Simple size adjustments and various loaded inductor of the open-slot resonator allow for easy control of the tag antenna resistance and inductive reactance, from which the chip impedance requirement can be easily obtained. The read range of the prototype antenna attached on a foam in the free space can reach more than 9 m, which has been tested for a radio frequency identification reader with 4.0-W of effective isotropic radiated power. Measurement data are in good agreement with simulation results. [ABSTRACT FROM PUBLISHER]

Background: Myopia-related maculopathy is one of the leading causes of blindness in the world. The prevalence of myopia has been reported as high as 90 % in some Asian countries. Therefore, controlling myopia progression is an urgent public issue. The purpose of this study is to evaluate the effects of topical atropine with different concentrations on intraocular pressure measurements and myopia progression in school-aged children in Taiwan.Methods: Fifty-six myopic children were divided into three groups: 32 children were treated with 0.125 % atropine eyedrop; 12 of them were treated with 0.25 % atropine eye drop and another 12 served as a control group. IOP, auto-refractor and manifest refraction were measured at baseline and every 3 months following treatment for one year.Results: There were no significant differences for the mean age, gender and baseline IOPs among the three groups. During the follow up period, no significant IOP difference was found among three groups. The change between final and baseline mean IOPs also revealed no significant differences: 0.54 mmHg, -1.28 mmHg, -0.33 mmHg for the 0.125 % atropine, 0.25 % atropine and control groups. The baseline mean spherical equivalent similarly did not differ significantly among groups but the control group showed a significant myopic progression compared to the 0.125 % atropine group 6 months after treatment, and persisted for one year. The change between final and baseline mean spherical equivalents were -0.05 D, 0 D, -1.05 D for the 0.125 % atropine, 0.25 % atropine and control groups, with both atropine-treated groups showing significant myopic retardation compared to the control group.Conclusions: Topical use of low concentration atropine for one year does not induce ocular hypertension and is effective for retarding myopic progression. However, further large scale studies with longer follow up period is necessary to validate the long term safety and efficacy.Trial Registration: ISRCTN33002849 , 2016/01/19, retrospectively registered. [ABSTRACT FROM AUTHOR]

A novel design for a radio-frequency identification (RFID) tag antenna mounted on a metallic plane is presented. The tag antenna has a rectangular radiating plate with a Z-shaped slot, which enables it to function like a half-wavelength slot resonator and a dipole-type ground radiator. A conjugate match to an Alien Higgs-3 chip with an impedance of 8 – j142 $\Omega$ at 925 MHz is obtained by etching a half-wavelength slot resonator in the center of the rectangular radiating plate (120 \text{ mm}\times60\text{ mm}). The tag antenna resistance and inductive reactance can be matched to the desired chip impedance by simply tuning the length and width of the Z-slot resonator. The space between the half-wavelength resonant radiating plate (dipole-type ground radiator) and the metallic plane enhances the antenna gain by increasing the reflection from the metallic plane. A horizontal electric dipole placed above the perfectly flat electric metallic plane enables a maximum gain of 8.7 dBi over a short distance, which is fourfold higher than that of an isolated half-wavelength dipole. Tests of an RFID reader with an effective isotropic radiated power of 4.0 W showed that the maximum read coverage of the proposed tag antenna mounted on a metallic plane exceeded 10 m. Measurement data were in good agreement with the simulation results. [ABSTRACT FROM AUTHOR]

Transplantation of ex vivo cultured limbal epithelial cells is proven effective in restoring limbal stem cell deficiency. The present study aimed to investigate the promoting effect of Y-27632 on limbal epithelial cell proliferation. Limbal explants isolated from human donor eyes were expanded three weeks on culture dishes and outgrowth of epithelial cells was subsequently subcultured for in vitro experiments. In the presence of Y-27632, the ex vivo limbal outgrowth was accelerated, particularly the cells with epithelial cell-like morphology. Y-27632 dose-dependently promoted the proliferation of in vitro cultured human limbal epithelial cells as examined by phase contrast microscopy and luminescent cell-viability assay 30 hours after the treatment. The colony forming efficacy determined 7 days after the treatment was enhanced by Y-27632 also in a dose-dependent manner. The number of p63- or Ki67-positive cells was dose-dependently increased in Y-27632-treated cultures as detected by immunofluorescent staining and western blotanalysis. Cell cycle analysis by flow cytometric method revealed an increase in S-phase proliferating cells. The epithelial woundclosure rate was shown to be faster in experimental group received topical treatment withY-27632 than the sham control using a rat corneal wounding model. These resultsdemonstrate that Y-27632 can promote both the ex vivo and in vitro proliferation oflimbal epithelial cell proliferation. The in vivo enhanced epithelial wound healingfurther implies that the Y-27632 may act as a new strategy for treating limbal stem cell deficiency. [ABSTRACT FROM AUTHOR]

A new ultra-high frequency radio frequency identification (RFID) tag antenna, which is comprised a U-shaped tuning stub and a dipole radiator for different permittivity surfaces is investigated, fabricated, and measured. For a conjugate match to the NXP G2XM chip impedance of 29–j137 at 915 MHz, a dipole tag antenna with U-shaped stubconnected to dipole arms was designed. Simple size adjustments of the U-shaped tuning stub and dipole radiator of the antenna allow for easy control of the antenna resistance and inductive reactance, from which the chip impedance requirement may be readily satisfied. The read range of the prototype antenna attached on a different permittivity surfaces (εr = 1–4) can reach more than 4.5 m, which has been tested for an RFID reader with 4.0 W of effective isotropic radiated power. The antenna structure consists of two dipole load bars and two loop electrically connected. The design offers more choice of freedom to tune the input impedance of the proposed antenna. Measurement data are presented which are in good agreement with simulation results. The design is suitable for mounting on all kinds of objects. The fabricated tag sensitivity of −3 dBm, read range of 7 m on the x–z and y–z planes, and the measured orientation radiation patterns were obtained in the desired frequency band. [ABSTRACT FROM PUBLISHER]

ABSTRACT A compact dual open-loop antenna is proposed to provide enhanced bandwidth in near-field applications in the ultra-high frequency band. The antenna generates a strong and uniform magnetic field in a near-field zone of the smaller open-loop antenna. For increased bandwidth, two open loops with individual half-wavelength perimeters are etched on each side of an FR4 printed circuit board. The antenna was fabricated in a compact overall size (dimensions, 60 × 60 × 0.8 mm3) and achieves an interrogation zone of 50 × 50 mm2 with good impedance matching and uniform magnetic field distribution in a 888-932 MHz band. Performance tests indicate that the proposed antenna has a reading distance of up to 130 mm for near-field applications and is suitable for radio frequency identification reader applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2008-2012, 2015 [ABSTRACT FROM AUTHOR]

A novel miniature folded square patch antenna is proposed and developed for Global Positioning System (GPS) receivers. Four different lengths of meander strips connected to the four edges of the square patch of a single coaxial-feed square patch antenna are folded to obtain a circularly polarized antenna. Properly positioning the coaxial feed on the square patch excites two orthogonal resonant modes with a 90^\circ phase difference and achieves a pure circular polarization. Conventional antennas for roof-mounted vehicle communication devices use commercially available ceramic corner-truncated patches whereas the proposed GPS antenna is designed to use a less expensive and more compact FR4 patch. Experiments also showed that mounting the proposed GPS antenna in different locations on the roof of a vehicle had little effect on circular polarization radiation. The fabricated prototype revealed an impedance bandwidth of 2.1% and a 3-dB axial-ratio bandwidth approximating 0.76% at a GPS frequency of 1575 MHz. Experiments confirmed that the characteristics of the proposed antenna were consistent with the simulation results. [ABSTRACT FROM PUBLISHER]

A novel, compact X-shaped slotted square-patch antenna is proposed for circularly polarized (CP) radiation. A cross-strip is embedded along the X-shaped slot for a novel proximity-fed technique to produce CP radiation in the UHF band. In the proposed design, two pairs of T-shaped slots are etched orthogonally on the square patch, connected to the center of the X-shaped slot for CP radiation and antenna size reduction. Proper adjustment of the length and coupling gap of the cross-strip will excite two orthogonal modes with 90^\circ phase difference for good CP radiation. Simulated and measured results indicate that the proposed structure can achieve circular polarization. A measured impedance bandwidth (VSWR\leq 2) of about 3.0% (909–937 MHz) and a 3-dB axial-ratio (AR) bandwidth of about 1.3% (917–929 MHz) were obtained. [ABSTRACT FROM AUTHOR]

This article deals with a decentralised service chain consisting of a service provider and a facility owner. The revenue allocation and service price are, respectively, determined by the service provider and the facility owner in a non-cooperative manner. To model this decentralised operation, a Stackelberg game between the two parties is formulated. In the mathematical framework, the service system is assumed to be driven by Poisson customer arrivals and exponential service times. The most common log-linear service demand and Weibull facility lifetime are also adopted. Under these analytical conditions, the decentralised decisions in this game are investigated and then a unique optimal equilibrium is derived. Finally, a coordination mechanism is proposed to improve the efficiency of this decentralised system. [ABSTRACT FROM AUTHOR]

To make good profits, pricing is a competitive weapon of service firms. This paper is concerned with pricing strategies for services with substantial facility maintenance costs. To address the problem, a mathematical framework that incorporates service demand and facility deterioration is proposed. The facility and customers constitute a service system driven by Poisson arrivals and exponential service times. The most common log-linear customer demand and Weibull-distributed facility lifetime are also adopted. By examining the linkage between customer demand and facility deterioration in profit model, pricing policies of the service are investigated. Then analytical conditions of customer demand and facility lifetime are derived to achieve a unique optimal pricing policy. Finally, numerical examples are presented to illustrate the effects of parameter variations on the optimal pricing policy. [ABSTRACT FROM PUBLISHER]

An UHF RFID tag antenna which is comprised of a trapezoidal loop and a dual-dipole radiator with an L-slit for omnidirectional polarized reading patterns is designed, fabricated and measured. For a conjugate match to the Monza 3 microchip impedance of 44-j231 at 915 MHz, an orthogonal dual-dipole tag antenna (91 mm \times 91 mm) with L-slit on each dipole arm was designed. Simple size adjustments of the L-slit and dipole radiator of the antenna allow for easy control of the antenna resistance and inductive reactance, from which the microchip impedance requirement may be readily satisfied. The read range of the prototype attached on a different glass can reach more than 9 m, which has been tested for an RFID reader with 4.0 W of EIRP. Good tag sensitivity and near omnidirectional radiation patterns were obtained in the desired frequency band. [ABSTRACT FROM PUBLISHER]

A microstrip-to-slotline transition technique is presented, for the coupling of a circularly polarized circular slot antenna in the ultrahigh frequency band.The fundamental TE11 mode of the circular slot antenna is investigated, using the magnetic current flow in the slot. In the proposed design, circular polarization (CP) is generated using a proper c-strip metal, within the circular slot structure, and connecting a strip metal to the circular slot edge, at −45° to the feeding slotline. The direct slotline feed is coupled to a 50-Ω microstrip line, on the opposite side of the substrate. Simulated and measured results indicate that the proposed structure achieves good CP radiation, in the TE11 mode. The impedance bandwidth and the 3-dB axial-ratio bandwidth for the design are approximately 22.1% and 2.5%, respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2016-2023, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27013 [ABSTRACT FROM AUTHOR]

For survival and success, pricing is an essential issue for service firms. This article deals with the pricing strategies for services with substantial facility maintenance costs. For this purpose, a mathematical framework that incorporates service demand and facility deterioration is proposed to address the problem. The facility and customers constitute a service system driven by Poisson arrivals and exponential service times. A service demand with increasing price elasticity and a facility lifetime with strictly increasing failure rate are also adopted in modelling. By examining the bidirectional relationship between customer demand and facility deterioration in the profit model, the pricing policies of the service are investigated. Then analytical conditions of customer demand and facility lifetime are derived to achieve a unique optimal pricing policy. The comparative statics properties of the optimal policy are also explored. Finally, numerical examples are presented to illustrate the effects of parameter variations on the optimal pricing policy. [ABSTRACT FROM PUBLISHER]

To produce circularly polarized (CP) radiation, a small, double-sided, crossed dipole antenna with two metal strips loaded for phase delay is proposed. The proposed antenna uses two orthogonal, unequal length dipoles, connected in parallel to a coaxial probe feed. It requires no matching network. The required power and phase relationships are obtained by proper choice of dipole lengths and the metal strips attached to them. The antenna also operates at its half wavelength orthogonal modes, for the UHF band. The phase delay metal strip generates the two resonant modes for CP radiation. Simulated and measured results indicate that the crossed dipole structure can produce CP radiation. An impedance bandwidth (VSWR \leq 2) of about 11.8% and a 3-dB axial-ratio (AR) bandwidth of about 3.3% around the center frequency of 925 MHz were measured. [ABSTRACT FROM PUBLISHER]

A compact circularly polarized coplanar crossed dipole antenna with an unequal length of arms for RFID reader is designed and measured in this paper. It uses two unequal length dipoles connected in parallel to a coaxial cable feed and requires no matching network. The impedance bandwidth of the proposed antenna for S <10 dB is about 6.9% and it has a 3-dB CP bandwidth of about 1.0%. Experimental results and simulations reveal that the proposed antenna features total size of 0.15 λ in side of square substrate and 0.005 λ in height at the center frequency 924 MHz. In addition to this, the compact antenna is easily to be embedded in the holding box as transmitting antenna in handheld RFID reader. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1172-1176, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25937 [ABSTRACT FROM AUTHOR]

Abstract: A novel reflection-based localized surface plasmon resonance fiber-optic probe for chemical and biochemical sensing is reported. The sensor is based on intensity measurement of the internal reflected light at a fixed wavelength from an optical fiber where the extinction cross-section of self-assembled gold nanoparticles on the unclad portion of the optical fiber changes with different refractive index of the environment near the gold surface. The reflection-based localized surface plasmon resonance fiber-optic probe has been shown to be capable of direct sensing of the “spectroscopically silent” Ni2+ ion and label-free detection of streptavidin and staphylococcal enterotoxin B at the picomolar level. [Copyright &y& Elsevier]

By using a pair of shorting pins, the dual-frequency operation of a single-feed rhombic microstrip antenna with a pair of slits is presented. This shorted dual-frequency microstrip antenna can result in a much reduced antenna size, and provide a tunable frequency ratio of ∼1.26–2.33 for the two operating frequencies by varying the inset slit length. Simulated results with the use of the software also have been conducted to study the characteristics of these antennas. Details of the proposed designs are described and discussed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 183–186, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10411 [ABSTRACT FROM AUTHOR]

Abstract: A new analytical method for aminoglycosides (kanamycin, bekanamycin, paromomycin and tobramycin) based on capillary electrophoretic separation and argon-ion laser-induced fluorescence detection has been developed. 6-Carboxyfluorescein succinimidyl ester (CFSE) was used for precolumn derivatization of the non-fluorescent aminoglycosides. Optimal separation and detection were obtained with an electrophoretic buffer of 30mM sodium borate (pH 9.0) and an air-cooled argon-ion laser (excitation at 488nm, emission at 520nm). The concentration limits of detection in aqueous solution were 3.9–8.2nM. Combined with a simple cleanup procedure, this method can be applied to the determination of aminoglycosides in human plasma. A calibration curve ranging from 0.15 to 30μM was shown to be linear. The limits of detection of aminoglycosides in human plasma were between 14.4 and 24.0nM. Recoveries of spiked aminoglycosides in human plasma were between 92 and 105%. [Copyright &y& Elsevier]

A dual-frequency rectangular microstrip antenna with a pair of π-shaped narrow slots close to the nonradiating edges of the patch is experimentally studied. By varying the length and spacing of the two arms of each π-shaped slot, the proposed antenna provides a tunable frequency ratio from about 1.03 to 1.19. Details of the antenna design and experimental results are presented and discussed. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 195–197, 2001. [ABSTRACT FROM AUTHOR]