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Objective: Alopecia areata (AA) is often characterized by sudden onset of patchy hair loss. Topical corticosteroid injection is the most common treatment. This study retrospectively observed the clinical efficacy of microneedle minoxidil combined with triamcinolone acetonide in the treatment of AA. Methods: A total of 230 patients with AA were selected. The experimental group (n = 120) received physician training and home microneedle treatment with minoxidil combined with triamcinolone acetonide once a week. Topical minoxidil and triamcinolone acetonide were used twice daily at other times. The control group (n = 110) was treated with minoxidil combined with triamcinolone acetonide, twice a day. Cure rate, response rate, SALT, dermatological Quality of Life Index (DLQI), visual analogue (VAS), and cost were assessed at weeks 4 and 12. Results: Treated group SALT score(Severity of Alopecia Tool) remarkable lower than control group after treated 4 and 12 weeks. After 12 weeks treatment, DLQI score of the treated group (1.8 ± 1.67) were significantly lower than those of the control group (2.45 ± 1.88) (p < 0.05). VAS score and adverse reaction between two group showed no significant different (p = 0.823, p = 0.484 respectively). The total cost was 53.93 ± 15.85 in the treatment group and 53.26 ± 11.51 in the control group. There was no significant difference between the two groups (p = 0.72). In the treated group, the complete response rate (CR: 78.33%) and total effective rate (CR+PR: 95%) were significantly higher than those in the control group (CR: 40.91% and CR+PR: 51.82%), with statistically significant differences (p < 0.001). Conclusion: Microneedle introduction of minoxidil and triamcinolone acetonide in the treatment of AA is a safe, effective, economical, and convenient method, with few adverse reactions, and has a good application prospect. [ABSTRACT FROM AUTHOR]

In this article we design triple-band parallel-coupled bandpass filters by using asymmetric parallel-coupled lines which have more degrees of freedom to satisfy the coupling rules in the triple bands. Stepped-impedance resonator is used with its controllable high-order resonance frequencies. Two examples of filters are presented, in which simulation and measurement results have good agreements. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2054–2058, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23553 [ABSTRACT FROM AUTHOR]

Novel and compact triple-mode resonators have been investigated and designed using split-ring resonator (SRR) to obtain three controllable resonant frequencies. An even/odd-mode method is proposed. The current distributions are computed by commercial software. Several triple-mode resonators are designed and fabricated. Both simulation and measurement results are presented to show the good performance of the resonators, which have excellent agreements. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2918–2922, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22955 [ABSTRACT FROM AUTHOR]

We have proposed a fast algorithm to study the electromagnetic (EM) scattering problems involving three-dimensional dielectric targets with inhomogeneous permittivity and permeability. Based on the volume equivalence principle, coupled volume integral equations are derived for the equivalent electric and magnetic current densities. Such integral equations are then solved using the conjugate gradient method combined with the fast Fourier transform (FFT), where the memory requirement is of the order N - the number of unknowns and the computational complexity is of the order N log N. The accuracy and efficiency of the proposed algorithm are verified by comparing numerical results with analytical results from the Mie series for dielectric spheres. We have applied the algorithm to investigate the EM scattering by small dielectric particles with high permittivity and permeability, which may be important to realize the artificial left-handed materials. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 305–310, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22116 [ABSTRACT FROM AUTHOR]

LC-loaded transmission lines and composite right/left-handed (CRLH) LC circuits have been applied to generate equivalent left-handed materials (LHM). In this paper, we propose a general representation of LHM using the mixture of CRLH circuits and transmission lines, along with the corresponding design formulations. The proposed structure can be easily used to produce an equivalent medium with the permittivity -ℇ0 and permeability -μ0 consisting of a small loss and retardation, which cannot be realized by previous structures with the microstrip lines in practice. This is very important to verify some LHM experiments such as the LHM superlens and electromagnetic-wave localization. Circuit simulations have been conducted to test the validity of the general structure. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2167–2171, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21883 [ABSTRACT FROM AUTHOR]

Many amazing properties of a novel electromagnetic (EM) structure, consisting a conducting grating backed with a left-handed material (LHM) slab, are studied. High-directivity, high-power emission and narrow-beam scanning can be easily realized when this structure acts as an antenna. Simultaneously, if it works as an imaging system, extremely high resolution can also be obtained with the unique EM behaviors of the LHM. Proper usage of surface waves on apertures opened in the conducting screen makes this structure possess such attractive capabilities. In order to investigate such phenomena, a more general EM model is first developed through the equivalence principle, and then the method of moments is implemented to obtain the interesting results. All these amazing properties are clearly observed through the numerical results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48:2359–2365, 2006;Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/mop.21944 [ABSTRACT FROM AUTHOR]

On the basis of the idealized structure of an atomic medium described by an assembly of independent oscillators, expressions for the stored electric and magnetic energy densities in absorptive and dispersive medium are derived. Such formulas are also valid for a left-handed medium (LHM), where the permittivity and permeability are simultaneously less than zero within a frequency band. These formulas are completely equivalent to those derived from a general definition of electromagnetic energy density using the classical electromagnetics. It has been shown that the stored energy densities, no matter in a right-handed medium or in a left-handed medium, are always positive. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2288–2291, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21899 [ABSTRACT FROM AUTHOR]

Open cavities are investigated using properly designed right-handed (RH) and left-handed (LH) transmission-line media (TLM), with detailed formulations to design TLM. We demonstrate large fields and high energies are concentrated at the center because of the resonance, which is a strong localization of electromagnetic waves and energies. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1662–1665, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21689 [ABSTRACT FROM AUTHOR]

A double-spiral resonator (DSR) structure causing negative permeability is proposed in this paper, which combines the characteristics of split-ring resonator (SRR) and spiral to reduce the resonant frequency. Hence, such a DSR structure has a small unit-to-wavelength ratio in realizing the left-handed property, which behaves more like a material. A quasi-static analysis is given to make an equivalence of the DSR structure to a left-handed material (LHM). Simulation results show that such an LHM possesses a small loss. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 923–926, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21520 [ABSTRACT FROM AUTHOR]

In order to clarify the micro-mechanics of clay during compression, the behavior of clay subjected to one-dimensional compression is investigated at the particle scale using discrete element method (DEM). The flaky clay particles in the simulation are approximated by clumps made of spheres. A new contact model is implemented to account for the double-layer repulsive force, the van der Waals attractive force and the mechanical contact force. The effect of sphere arrangement in the particle clump is discussed. The DEM model is validated against experimental observations in terms of macroscopic compressibility, particle dip angle as well as the over consolidated behavior. The e-logσv curve shows a concave-to-linear shape. The evolution of dip angle of clay particles indicates that particles tend to have an anisotropy with a preferential orientation towards horizontal direction. The increase of preconsolidation pressure decreases the initial compressibility due to the increase the number of mechanical contacts. The evolution of average coordination and sphere-sphere contact shows that the majority of mechanical contacts are generated before the compressive stress reaches 100 kPa. Evolution of soil fabric is presented and discussed. [ABSTRACT FROM AUTHOR]

A space-time coding metasurface (STCM) operating in the sub-terahertz band to construct new-architecture wireless communication systems is proposed. Specifically, a programmable STCM is designed with varactor-diode-tuned metasurface elements, enabling precise regulation of harmonic amplitudes and phases by adjusting the time delay and duty cycle of square-wave modulation signal loaded on the varactor diodes. Independent electromagnetic (EM) regulations in the space and time domains are achieved by STCM to realize flexible beam manipulations and information modulations. Based on these features, a sub-terahertz wireless communication link is constructed by employing STCM as a transmitter. Experimental results demonstrate that the STCM supports multiple modulation schemes including frequency-shift keying, phase-shift keying, and quadrature amplitude modulations in a wide frequency band. It is also shown that the STCM is capable of realizing wide-angle beam scanning in the range of ±45°, which offers an opportunity for user tracking during the communication. Thus, the STCM transmitter with high device density and low power consumption can provide low-complexity, low-cost, low-power, and low-heat solutions for building the next-generation wireless communication systems in the sub-terahertz frequency and even terahertz band. [ABSTRACT FROM AUTHOR]

The title molecule, C20H18, lies on a crystallographic inversion centre. The dihedral angle between the unique phenyl ring and the central benzene ring is 88.39 (11)°. [ABSTRACT FROM AUTHOR]

Two high-gain broadband 60 GHz integrated planar patch array antennas, without and with air cavity, are designed and implemented on Rogers 5880 substrate. The differential antenna structure is used to improve the signal integrity at millimetre-wave frequencies. The antennas are co-designed with bonding wires of which the parasitic effect is compensated using a passive network. The proposed antennas have the advantages of symmetrical radiation pattern, wide bandwidth and low insertion loss. In the measurement, a differential transmission line based de-embedding structure is developed on silicon, mimicking the real chip packaging environment and providing reliable terminations for antennas. The measured fractional bandwidths (|S11| < -10 dB) are 13.8 and 26.2%, respectively, for the two structures without and with air cavity, including the effect of a waveguide-to-microstrip line transition and a branch-line balun. Both antennas have measured gain of about 12 dBi. After de-embedding the return loss, the measured insertion loss of the bond wire compensation network is only 0.07 dB at 61 GHz. [ABSTRACT FROM AUTHOR]

In this Letter, a wireless transmitter using the new architecture of programmable metasurface is presented. The proposed transmitter does not require any filter, nor wideband mixer or wideband power amplifier, thereby making it a promising hardware architecture for cost-effective wireless communications systems in the future. Using experimental results, the authors demonstrate that a programmable metasurface-based 8-phase shift-keying (8PSK) transmitter with 8 × 32 phase adjustable unit cells can achieve 6.144 Mbps data rate over the air at 4.25 GHz with a comparable bit error rate performance as the conventional approach without channel coding, but with less hardware complexity. [ABSTRACT FROM AUTHOR]

In the title compound, C22H23BF2N2O, the styrene and boron-dipyrromethene (BODIPY) fused-ring fragments are almost coplanar. Short C—C bond lengths suggest some electronic conjugation between the two systems. [ABSTRACT FROM AUTHOR]

Aim: A cross-section study was conducted to explore the association between polymorphism of δ-aminolevulinic acid dehydratase (ALAD) and lead poisoning in Uygur and Han children in China. Methods: The ALAD genotyping was determined by PCR-RFLP in 443 Uygur and 469 Han children aged 6–10 years from Urumqi in Xinjiang province. Results: The blood lead levels of 912 environmentally exposed children ranged from 0.5 to 48.2 μg/dL, with a mean of 5.45 μg/dL and a standard deviation of 0.22 μg/dL, and 23. Thirty-one percent individuals were with blood lead level ≥10 μg/dL. The mean and standard deviation of blood lead levels were 5.57 ± 0.223 μg/dL and 5.30 ± 0.224 μg/dL in Uygur and Han children, respectively. The frequencies of the allele ALAD1 and ALAD2 in Uygur subjects were 90.52% and 9.48%, and in Han subjects were 95.73% and 4.27%, respectively (chi-square = 19.55, p < 0.05). No statistic correlation between the distribution of ALAD alleles and the blood lead level was found in both populations. Conclusion: A significant difference was seen in the frequency distribution of ALAD genotype between the different races. The genetic susceptibility of ALAD polymorphism to lead toxicity may exhibit in a lead dose-dependent manner. [ABSTRACT FROM AUTHOR]

An efficient method is presented to design the evanescent wave amplification exactly by cascading two layers of periodic series-shunt capacitors and inductors, which simulate a bilayer of magnetic and electric plasmas. Based on the presented method, equivalent lumped parameters of circuit structures are retrieved, from which the evanescent-wave amplification (EWA) is obtained at a designed frequency. Full-wave simulations show that the relative offset of the EWA frequency is less than 0.1%. The structure has been fabricated and measured, and the measurement results have good agreements with the simulation results. The proposed method can be used to design other periodic circuit structures, and the exact design of EWA can be used in the fabrication of novel components. © Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1870–1873, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23501 [ABSTRACT FROM AUTHOR]

Objective To determine the bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The effect of breed, sex and age of dogs and season on the presence or absence of bacteria in the conjunctival sac of clinically normal dogs was evaluated. Sample population This investigation included 240 healthy dogs, 27 dogs with unilateral corneal ulcer and one dog with bilateral corneal ulcer. Procedure The 480 samples from healthy dogs and the 29 samples from dogs with ulcerative keratitis were incubated in an aerobic and 5% CO2 environment at 37 °C for 48 h. Logistic regression analysis was performed. Statistical significance was set at P < 0.01. Results Of 480 normal eyes, Staphylococcus spp. were the most frequently isolated organisms (40.29%). Neisseria spp. (11.47%) were the next most frequently isolated organisms, followed by Corynebacterium spp. (9.4%). Of 29 eyes with ulcerative keratitis, Staphylococcus spp. were also the most frequently isolated bacteria (47.06%). Streptococcus spp. (12.94%) and Pseudomonas spp. (8.24%) were the second and third, respectively. Season ( P = 0.002) was a significant factor influencing presence or absence of bacterial microorganisms in the conjunctival sac of normal dogs in Beijing, China, while the effects of breed ( P = 0.095), sex ( P = 0.588) and age ( P = 0.866) of dogs were insignificant. Conclusion Staphylococcus spp. were the most frequently isolated organisms, and S. intermedius predominated in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The likelihood of detecting bacteria depends on the season. [ABSTRACT FROM AUTHOR]

A band-stop filter based on spoof surface plasmon polaritons for microwave applications is proposed, which can realise high-efficiency band rejections by etching gradient semi-circular grooves on both sides of the middle stripline of coplanar waveguide. The operating bandwidth and frequency of band-stop can be controlled by changing the radii of semi-circular holes and the length of unit cell, respectively. The operating principle of the designed band-stop filter is explained by the dispersion curves and electric field distributions. Parametric studies are also conducted to analyse the effects of key parameters on the performance of the band-stop filter, which is useful for practical designs. A prototype of the band-stop filter is fabricated and measured. The good agreements between the simulated and measured results validate the proposed design, which indicate that the presented band-stop filter can be potentially useful in many microwave applications. [ABSTRACT FROM AUTHOR]

The article discusses the technological innovations in mobile communication with a major focus on ultra reliable low latency communications (URLLC) in fifth generation networks. Topics discussed include the importance of multiple-input multiple-output (MIMO) antennas, programmable metasurface for transmitting wavelengths and innovation in high-resolution videos and 4K virtual reality.