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Background: Lymphoma is the most common secondary cause of hemophagocytic lymphohistiocytosis (HLH) in adults. Lymphoma‐associated HLH (LA‐HLH) in the elderly population is not rare, however, little has been reported regarding clinicopathological characteristics, prognostic factors, and outcomes of LA‐HLH in the elderly population. Methods: We retrospectively analyzed a multicenter cohort of elderly patients with LA‐HLH. Clinicopathological features and treatment information were collected. The impacts of baseline characteristics and treatments on survival outcomes were analyzed. Results: A total of 173 elderly patients with LA‐HLH were included. Compared with young patients, elderly patients showed different clinical and laboratory features. Regarding lymphoma subtypes, B‐cell lymphoma was more common in elderly patients (elderly 61.3% vs. young 32.3%, p < 0.001) while T/NK‐cell lymphoma was more common in young patients (65.3% vs. 35.3%, p < 0.001). The median survival of elderly patients with LA‐HLH was only 92 days. The prior use of HLH therapy or etoposide‐containing HLH therapy was not associated with improved overall survival. T/NK‐cell subtype, a lower platelet count (≤53 × 109/L), a lower albumin level (≤32.1 g/L), a higher LDH level (>1407 U/L), and a higher creatinine level (>96.8 μmol/L) were independent predictors of decreased overall survival and 60‐day survival. A prognostic index was established and demonstrated to be robust in predicting the overall survival and 60‐day survival of elderly patients with LA‐HLH. Conclusions: LA‐HLH in elderly patients displayed heterogeneous clinicopathological features and survival outcomes. Treatments need to be optimized to improve the outcomes of elderly patients with LA‐HLH. [ABSTRACT FROM AUTHOR]

SnSe‐based materials have attracted widespread attention in thermoelectrics due to their outstanding thermoelectric performance. However, the pristine and unmodified polycrystalline SnSe reveals poor electrical properties. Doping and constructing nanostructured composite architectures to produce energy filtering effect proved to be an effective method to strengthen thermoelectric performance. In this study, Ti3C2/Sn0.98Cd0.02Se composites are successfully fabricated by the solvothermal method combined with the electrostatic self‐assembly method and spark plasma sintering. The phase interface introduced by incorporating Ti3C2 into Sn0.98Cd0.02Se can effectively filter low‐energy carriers due to its generation of energy barriers, thereby the Seebeck coefficient of x wt% Ti3C2/Sn0.98Cd0.02Se x = (0.05, 0.5, 1) samples is better than that of the pristine Sn0.98Cd0.02Se over the whole temperature range. Meanwhile, high conductivity was also obtained in 1 wt% Ti3C2/Sn0.98Cd0.02Se sample so that the high power factor of 3.31 μWcm−1K−2 was acquired at 773 K. Ultimately, a peak ZT value of 0.41 was obtained at 773 K, compared with pristine Sn0.98Cd0.02Se, and the thermoelectric performance improved by 24%. This study offers an available approach to efficiently enhance the thermoelectric properties of polycrystalline SnSe‐based materials. [ABSTRACT FROM AUTHOR]

Taking advantage of multimaterial additive manufacturing, this work demonstrates a kind of polarization‐maintaining metasurface (MS) for spin‐decoupled beam shaping. The wavefronts of the two spin states, i.e., the left‐hand circular polarization (LHCP) and the right‐hand circular polarization (RHCP), can be independently manipulated while the output spin state remains the same as the input. The meta‐atom is implemented with dual‐polarized antennas at the top and the bottom with phase delay lines connecting them. The dual‐polarized antenna on the receiving side is fixed to receive the LHCP/RHCP incident waves, while the dual‐polarized transmitting antenna is rotated, providing the opposite phase shifts for the LHCP and RHCP. The absolute value of the phase shift is the same as the transmitting antenna's rotation angle. Meanwhile, varying the length of phase delay lines introduces 2π phase shifts for both LHCP and RHCP inputs. Thus, combining the two phase‐shifting degrees of freedom, the LHCP and RHCP wavefronts can be independently controlled while the polarization is not flipped after transmitting through the MS. One MS produces vortex beams with different topological charges for LHCP and RHCP. The other achieves spin‐decoupled focusing. The multilayered MSs are conveniently printed using multimaterial additive manufacturing without postprocessing. [ABSTRACT FROM AUTHOR]

A set of four planar‐chiral sila[1]ferrocenophanes equipped with a benzyl group in the α‐position, either on one or both Cp rings, and substituted on the bridging silicon atom, either by methyl or phenyl groups, were prepared. While NMR, UV/Vis, and DSC measurements did not show anything uncommon, single crystal X‐ray analyses revealed unexpectedly large variations of the dihedral angles between both Cp rings (α tilt angle). While DFT calculations predicted α between 19.6 and 20.8°, measured values were found between 16.6(2) and 21.45(14)°. However, experimentally determined conformers differ significantly from those calculated for the gas phase. For the sila[1]ferrocenophane with the largest mismatch between the experimental and predicted α angle, it was shown that the orientation of benzyl groups have a significant influence on the ring‐tilted structure. Packing of molecules in the crystal lattice forces benzyl groups into unusual orientations, resulting in a significantly reduced α angle through steric repulsions. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the clinical characteristics, internal correlations and risk factors for different locations of retinoschisis (RS) in an elderly high myopia (HM) population. Methods: A total of 448 eyes (304 participants) were analysed and classified into no retinoschisis (no‐RS), paravascular retinoschisis (PVRS), peripapillary retinoschisis (PPRS) and macular retinoschisis (MRS) groups. Each participant underwent comprehensive ophthalmic examinations, and posterior scleral height (PSH) was measured in swept‐source optical coherence tomography images. PSH, vitreoretinal interface abnormities and myopic atrophy maculopathy (MAM) were compared among groups. Results: Retinoschisis was found in 195 (43.5%) eyes, among which 170 (37.9%) had PVRS, 123 (27.5%) had PPRS, and 103 (23.0%) had MRS. MRS was found to be combined with PVRS in 96 of 103 (93.2%) eyes. MAM was one of the risk factors for RS (odds ratio [OR], 2.459; p = 0.005). Higher nasal PSH was the only risk factor for PVRS (OR, 9.103; p = 0.008 per 1‐mm increase). Elongation of axial length (AL) (OR, 1.891; p < 0.001 per 1‐mm increase), higher PSH in nasal (OR, 5.059; p = 0.009 per 1‐mm increase) and temporal (OR, 13.021; p = 0.012 per 1‐mm increase), epiretinal membrane (ERM; OR, 2.841; p = 0.008) and vitreomacular traction (VMT; OR, 7.335; p = 0.002) were risk factors for MRS. Conclusions: Paravascular retinoschisis is the most common type of RS in HM and MRS is mostly combined with PVRS. MAM is one of the risk factors for RS. In addition to longer AL and higher PSH, the presence of VMT and ERM also play an important role in the formation of MRS. [ABSTRACT FROM AUTHOR]

This article proposes 3D printed broadband transmissive metasurfaces for spin‐decoupled wavefront shaping based on a versatile broadband cross‐polarization rotation meta‐atom. A meta‐atom combining broadband cross‐linear polarization dynamic phase and Pancharatnam–Berry (P–B) phase is demonstrated to realize spin‐decoupled beam shaping. The meta‐atom is built in an antenna‐circuit‐antenna fashion. Stacked patch antennas are used here as both the receiving and transmitting antennas because they can achieve wide bandwidth and good impedance matching to free space. By carefully selecting the phase delay lines' path, the meta‐atom converts the x‐polarized or y‐polarized linear incident wave to its cross‐polarization with the co‐polarized components suppressed. The function also leads to the spin conversion for the circularly polarized incident wave. Thus, P–B phase‐shifting will be introduced when the meta‐atom is rotated. In addition, the transmission line provides the same dynamic phase delay for both left‐ and right‐hand circular polarization (LHCP and RHCP) incident waves. Then, combining the two different phase‐shifting methods, i.e., the P–B phase and dynamic phase, the LHCP and RHCP wavefront can be fully decoupled. Two different metasurfaces achieving spin‐decoupled anomalous refraction carrying orbital angular momentum (OAM) with different topological charges are simulated and experimentally verified for demonstration. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the association between morphological characteristics of Bruch's membrane opening distance (BMOD), border length (BL), border tissue angle (BTA), peripapillary atrophy (PPA) as well as axial length (AL) and incident decreased macular choroidal thickness (mChT) in young healthy myopic eyes. Methods: A total of 323 participants aged 17–30 years were included in the current 2‐year longitudinal study. Each participant underwent detailed ocular examinations at baseline and follow‐up. Data of AL, refraction error, PPA area, BMOD, BL, BTA and mChT were measured individually. Incident decreased mChT was defined as follow‐up mChT of participants decreased into the lowest quartile of baseline mChT. Results: Subjects with longer AL, longer BMOD were more likely to have incident decreased mChT (odds ratio [OR], 1.56; 2.09, respectively, per 1 Z‐score increment), whereas larger BTA was less likely to develop decreased mChT (odds ratio [OR], 0.51, per 1 Z‐score increment). The area under the receiver operating curve (AUROC) of basic risk model for incident decreased mChT was 0.6284. After adding BMOD, BTA and AL separately to the basic risk model, the AUROC of the combination could reach 0.6967, 0.6944 and 0.7383, respectively. After combining BMOD, BTA and AL to the basic model, the AUROC of the combination showed the highest AUROC of 0.7608. Conclusions: Bruch's membrane opening distance and AL are significant risk factors for incident decreased mChT, whereas BTA played protective role in the deterioration of mChT. In addition, a combination of BMOD, BTA and AL could serve as earlier predictors of the attenuation of mChT in myopia progression. [ABSTRACT FROM AUTHOR]

Arbitrarily manipulating the polarization and wavefront of electromagnetic waves using ultrathin and highly efficient devices is desirable for many systems. Ultrathin broadband polarization‐insensitive transmissive metasurfaces, which can achieve the same polarization conversion and wavefront shaping for arbitrary linearly polarized incident waves, are proposed. The meta‐atom is composed of a transmitting antenna and a receiving antenna with a group of phase delay lines connecting them. The rotation of the transmitting antenna introduces the polarization conversion, and the different lengths of the transmission lines provide [−π, π] phase shift for wavefront shaping. Both the polarization conversion and wavefront shaping functions are polarization insensitive. Differential feeding is applied to both the transmitting and the receiving patch antennas to improve the transmission efficiency. The prototypes are conveniently printed by using the additive manufacturing technique. Two polarization‐insensitive metasurfaces are designed and measured to demonstrate. One of them produces vortex beams with 90° polarization conversion, and the other achieves anomalous refraction with 45° polarization conversion. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the percentages and risk factors for visual impairment (VI) across age groups in a highly myopic cohort with a wide range of age (18–93 years). Methods: A total of 2099 eyes (1220 participants) were enrolled. All participants underwent detailed ocular examinations. Myopic maculopathy (MM) was assessed as myopic atrophy maculopathy (MAM), myopic traction maculopathy (MTM) or myopic neovascular maculopathy (MNM) based on the ATN system. Results: Most participants younger than 50 years had normal vision, while the cumulative risk of VI and blindness gradually increased after 50–59 years. The percentage of each type of MM increased nonlinearly with ageing (all p < 0.001), with an accelerated period of increase after 45 years for MAM, and after 50 years for MTM and MNM. Axial length (AL) ≥30 mm was the only associated factor for mild VI or worse in participants aged 18–39 years (p < 0.001). Older age, AL ≥30 mm and the presence of MAM were predictors for mild VI or worse in the group aged 40–49 years (all p < 0.05). In participants aged ≥50 years, older age, female sex, longer AL and increased severity of MM were risk factors for VI and blindness (all p < 0.05). Conclusion: The percentages of MM and related VI increased nonlinearly with older age, with a turning point at 45 years for MAM, preceding that of MTM, MNM and VI by 5 years, warranting future longitudinal studies to confirm. Different age groups presented different risk factors for VI. Timely screening should be in place for middle‐aged high myopes. [ABSTRACT FROM AUTHOR]

Purpose: To determine the characteristics of crystalline lens with varying refractive errors and relationship with axial elongation in young school children. Methods: A total of 1465 children aged 6–8 years were examined annually for 2 years. Each participant underwent a series of ophthalmic examinations, including cycloplegic autorefraction, crystalline lens and axial length measurement. Crystalline lens power was determined, and factors associated with different refractive statuses were investigated. Results: Crystalline lens power decreased with time; reduction in lens power in Year 1 was greater in children with emmetropia (−0.69 ± 0.59 dioptre [D]) than in those with hyperopia (−0.49 ± 0.56 D) or myopia (−0.45 ± 0.55 D) (p < 0.001). Among the emmetropes, there were no differences in loss of crystalline lens power between those who remained emmetropic (−0.63 ± 0.59 D) and those who became myopic at Year 1 (−0.74 ± 0.61 D) and Year 2 (−0.77 ± 0.57 D, p > 0.05) visits. Among myopes at Year 1 visit, there was a greater reduction at Year 2 in those who had baseline emmetropia (−0.61 ± 0.51 D) than those who had baseline myopia (−0.26 ± 0.49 D, p < 0.001). The trend was similar among children of the same age. There was a significant correlation between changes in lens power and axial elongation in non‐myopia (β = −0.954, p < 0.001) and new myopia (β = −1.178, p < 0.001), but not in established myopia (β = −0.001, p = 0.539). Conclusions: There is accelerated loss of lens power in emmetropia and early stage of myopia. However, this loss is retarded when myopia persists and is accompanied by disappearance of the compensatory effect of lens power against axial elongation. These findings provide new insights into human refractive development. [ABSTRACT FROM AUTHOR]

The Linfen kiln complex, one of the most representative of Shanxi kilns, is famous for its oil spotted glazed ware production. In this work, micro‐Raman spectroscopy was applied to analyze the nature of the rusty oil spot pattern of a bowl fragment from Linfen kilns. Crystals of polygonal shape found in the spots at the glaze surface and around bubbles in the cross‐section of the glaze were identified as hematite. Their distribution in the glaze suggests that nucleation seeds and small crystals are carried toward the surface by the rise of bubbles during the heating step of the firing. Raman spectra combined with energy‐dispersive spectrometry (EDS) measurements also suggest that Fe ions in hematite crystals are partially substituted, causing the variation of band position and full width at half maximum (FWHM) of the spectra. Dendritic ε‐Fe2O3 was identified in brown areas of the black glaze, as well as pseudobrookite crystals of tens of microns in the cross‐section of the glaze. The degree of the glaze polymerization (A500/A1000) was calculated at 1.85, indicating a firing temperature lower than 1300°C, consistent with the archaeological data. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the prevalence and associated factors of fundus tessellation in highly myopic children and adolescents. Methods: A total of 513 high myopes (spherical equivalent [SE] ≤ −5.0 D, 4–19 years of age) without any advanced pathological myopic lesions were enrolled. Fundus photographs and choroidal thickness (ChT) data were collected by SS‐OCT. A novel grading approach was adopted to classify fundus tessellation into four categories on colour fundus photography, referring to the location of tessellation divided by an Early Treatment Diabetic Retinopathy Study grid centred on the fovea, through which closer to the fovea represents higher grades of fundus tessellation. Peripapillary atrophy (PPA) area and ovality index were also measured. Results: Among the participants, with a mean age of 13.47 ± 3.13 years and mean SE of − 8.34 ± 1.91 D, there were 29 (5.7%), 95 (18.5%), 233 (45.4%) and 156 (30.4%) participants with grade 0 to grade 3 fundus tessellation, respectively. The ChT in both the macular and peripapillary area was negatively correlated with the fundus tessellation grade (R = −0.763 and −0.537, respectively, all p < 0.001). Higher grades of fundus tessellation were independently associated with thinner macular ChT (OR = 1.734, 95% CI: 1.621–1.856, p < 0.001), longer axial length (OR = 1.368, 95% CI: 1.105–1.695, p = 0.004), larger PPA area (OR = 1.391, 95% CI: 1.073–1.802, p = 0.013) and the female sex (OR = 1.605, 95% CI: 1.092–2.359, p = 0.016). Conclusion: The fundus tessellation grade could reflect the ChT, representing the severity of myopic maculopathy among young high myopes who rarely had any advanced lesions of pathological myopia. Fundus tessellation grade might be a potential index for assessing early‐stage myopic maculopathy in children and adolescents. [ABSTRACT FROM AUTHOR]

Purpose: To document one‐year changes in refraction and refractive components in preschool children. Methods: Children, 3–5 years old, in the Jiading District, Shanghai, were followed for one year. At each visit, axial length (AL), refraction under cycloplegia (1% cyclopentolate), spherical dioptres (DS), cylinder dioptres (DC), spherical equivalent refraction (SER) and corneal curvature radius (CR) were measured. Results: The study included 458 right eyes of 458 children. The mean changes in DS, DC and SER were 0.02 ± 0.35 D, −0.02 ± 0.33 D and 0.01 ± 0.37 D, while the mean changes in AL, CR and lens power (LP) were 0.27 ± 0.10 mm, 0.00 ± 0.04 mm and − 0.93 ± 0.49 D. The change in the SER was linearly correlated with the baseline SER (coefficient = −0.147, p < 0.001). When the baseline SER was at 1.05 D (95% CI = 0.21 to 2.16), the change in SER was 0 D. The baseline SER was also linearly associated with the change in LP (coefficient = 0.104, p = 0.013), but not with the change in AL (p = 0.957) or with the change in CR (p = 0.263). Conclusion: In eyes with a baseline SER less than +1.00 D, LP loss was higher compared to axial elongation, leading to hyperopic shifts in refraction, whereas for those with baseline SER over this range, loss of LP compared to axial elongation was reduced, leading to myopic shifts. This model indicated the homeostasis of human refraction and explained how refractive development leads to a preferred state of mild hyperopia. [ABSTRACT FROM AUTHOR]

Firing temperature is an essential indicator for the level of the manufacturing technology of ancient ceramics. Current techniques for measuring the firing temperature of ceramics are generally destructive and very complex. In this work, a series of celadon fragments were prepared at different firing temperatures (from 900 to 1,300°C) and studied by Raman spectroscopy, X‐ray fluorescence (XRF), and X‐ray diffraction (XRD). The XRD results show that raw materials were dissolved and melted completely to form the glass matrix of a glaze above 1,100°C. Besides, the results of XRF and Raman tests demonstrate that CaO amounts in the glaze decrease significantly with the increase in firing temperatures, which is the main factor to influence the Si–O linkages, adjust Q1, Q2, and Q3–4 components, and modify the structure of the glass matrix during the firing process. The area ratios of the Si–O bending over stretching envelopes (A500/A1,000) of the glassy matrix have a negative correlation to the CaO amount. In contrast, the value has an apparent positive correlation to the firing temperature. The A500/A1,000 value of the glass matrix increases from 1.29 to 2.40 as the firing temperature increases from 1,100°C to 1,300°C. These results prove that Raman spectroscopy could be used as a feasible and reliable nondestructive method to establish a more accurate relationship between Raman spectral polymerization index and the firing temperature in order to identify the firing temperature of ancient ceramics. [ABSTRACT FROM AUTHOR]

Purpose: To describe the methodology and pilot data of the Shanghai Child and Adolescent Large‐scale Eye Study (SCALE‐HM). Methods: This is a population‐based, prospective, examiner‐masked study with annual follow‐up. Patients are 4‐ to 18‐year‐olds with high myopia. The participants will fill out questionnaires and then undergo visual acuity, axial length (AL), intraocular pressure, ophthalmologist assessment, microperimetry, cycloplegic refraction, Pentacam, wavefront aberration, fundus, blood and saliva examinations. To describe the pilot data, intergroup differences were assessed with t‐tests or analysis of variance and a logistic regression model was used to determine the independent factors associated with peripapillary atrophy (PPA). Results: Overall, 134 eyes of 79 participants met the pilot study recruitment criteria. The mean AL and spherical equivalent were 26.91 ± 1.07 mm and −9.40 ± 1.77 D, respectively. Peripapillary atrophy (PPA) (N = 112) and tessellated fundus (N = 67) were the most common fundus changes. The mean AL was significantly longer in PPA (27.08 ± 0.93 mm) than in non‐PPA eyes (26.06 ± 1.31 mm; p < 0.001). Axial length (AL) (p = 0.041) was the only independent factor associated with PPA. Axial length (AL) was significantly longer in eyes with diffuse chorioretinal atrophy (N = 11; 28.02 ± 1.31 mm) than without myopic retinal lesions (N = 56; 26.48 ± 0.91 mm, p < 0.001) or with tessellated fundus (N = 67; 27.09 ± 0.97 mm, p = 0.012). The myopic degree was higher in eyes with diffuse chorioretinal atrophy than without myopic retinal lesions (−10.51 ± 2.76 D versus −9.06 ± 1.58 D, p = 0.039). Conclusion: Peripapillary atrophy and tessellated fundus were common in children and adolescents with high myopia. Results from this prospective study will help to understand the mechanisms, development and prognosis of these changes and can guide early myopia screening. [ABSTRACT FROM AUTHOR]

Background: Although an integral part of ethical and quality health care, little is known about the informed decision making of Chinese women with different socioeconomic backgrounds within the context of antenatal testing. Methods: To explore women's viewpoints on informed decision making regarding antenatal screening, a Q‐methodology study that combines both quantitative factor analysis and interviews was conducted between June 2016 and February 2017 in Shanghai and Duyun. A total of 169 women (84 Shanghai and 85 Duyun) participated in the study of 41 ranked statements along a Q‐sorting grid. Results: Using by‐person factor analysis, five distinct viewpoints are identified: (a) choice is shared with the partner/husband, but the mother has the right to make the final decision; (b) having antenatal tests is not about choice but about a mother's responsibility; (c) choice is a shared decision led primarily by the partner/husband and secondarily by the doctors; (d) choice should be made using the advice of doctors, but the decision should be made with the partner/husband; and (e) choice is a responsibility shared with the partner, family and doctors. Conclusions: The study reveals that women with better education and higher incomes demonstrate more autonomy than those with less education. The nuclear family clearly emerges as the main decision makers in health‐care services in China. Patient and Public Contribution: The 169 participants shared their views and stories for at least an hour. They were debriefed after the interviews and contributed their thoughts on our study design and interpretation of the data. [ABSTRACT FROM AUTHOR]

The performance of durability in direct methanol fuel cell (DMFC) is of great significance. In this study, NiCo2O4 with three‐dimensional ordered hierarchical pore was applied as oxygen reduction reaction electrocatalyst to enhance the long‐term stability in passive DMFC. The peak power densities of NiCo2O4‐based DMFC were 14.78 and 26 mW cm−2 at 15 and 40 °C, respectively. In the durability test, NiCo2O4‐based DMFC could operate continually for 1406 hours, which is approximately 6 times higher than the highest values reported in literature. And the outstanding durability could be mainly ascribed to the interconnected and ordered macropores channel in NiCo2O4, which could act as a structural buffer to mitigate the structural changes in porous nano‐catalysts, and also significantly facilitate the mass transport and the rapid elimination of cathodic product to solve the problem of "water flooding" at the cathode. [ABSTRACT FROM AUTHOR]

Cataract is the leading cause of blindness in the world while the molecular mechanisms of cataracts pathogenesis are not well elucidated. Dysregulated microRNA (miRNA) expressions have been implicated in cataract. However, the precise role of miR‐4328 in cataract is still unknown. We compared the expression level of total miR‐4328 between clinical samples from healthy people and cataract patient and between UV‐irradiated and control lens epithelial cells. We determined the effect of miR‐4328 on lens epithelial cell proliferation and apoptosis by suppressing miR‐4328. We further predicted NLR Family Apoptosis Inhibitory Protein (NAIP) as potential target of miR‐4328 and continued to evaluate the effects of NAIP on cell proliferation and apoptosis. MiR‐4328 was up‐regulated in cataract sample and in UV‐irradiated lens epithelial cells. Suppressing MiR‐4328 promoted cell proliferation and inhibited apoptosis. MiR‐4328 targeted NAIP and suppressed its expression. Knocking down NAIP abolished the effects of miR‐4328 on cell proliferation and inhibited apoptosis. MiR‐4328 promotes lens epithelial cell apoptosis by targeting NAIP in age‐related cataract. Significance of the study: MiR‐4328 targeted NAIP and suppressed its expression. Knocking down NAIP abolished the effects of miR‐4328 on cell proliferation and inhibited apoptosis. MiR‐4328 promotes lens epithelial cell apoptosis by targeting NAIP in age‐related cataract. [ABSTRACT FROM AUTHOR]

Improving the stability of all‐inorganic halide perovskite nanocrystals has become an urgent task that cannot be ignored in practical applications. Lead halide perovskite CsPbX3 (X = Br, I, Cl) compounds are considered as the potential materials for next‐generation light‐emitting devices due to their superior optical properties. However, they are threatened by thermal degradation and atmospheric moisture. In order to better solve this practical problem, CsPbBr3 quantum dots (QDs) and CsPbBr3@Cs4PbBr6 nanocrystals (NCs) are tested under heating and cooling cycles, and the photoluminescence (PL) intensity loss of different perovskite materials at high temperatures is investigated. In addition, a thermoplastic polyurethane encapsulation strategy is proposed to improve their properties of thermal degradation and moisture resistance. This inexpensive and convenient method not only greatly reduces the PL intensity loss, but also shows excellent PL performance even in water. The encapsulated material has both flexible and elastic properties, which paves the way for the next commercial processing of all inorganic perovskite materials. [ABSTRACT FROM AUTHOR]

Silicon‐bridged [1]ferrocenophanes are a versatile class of monomers to obtain well‐defined metallopolymers, however, their boron‐bridged analogues are far less utilized despite being significantly higher strained. We assumed that the reactivity of known bora[1]ferrocenophanes towards ring‐opening polymerization is hampered by π‐donating R2N groups at the bridging boron atom and therefore prepared the first bora[1]ferrocenophanes lacking such electronic stabilization. The new, isolated ferrocenophane with a 2,4,6‐triisopropylphenyl group attached to the bridging boron atom exhibits the most tilted Cp rings among all isolated strained sandwich compounds [α(DFT)=33.3°] with a measured record value of the bathochromic shift (λmax=516 nm). Attempts to purify the mesityl analogue by vacuum sublimation transformed this monomer to a purple‐colored polymer that resulted in Cotton effects in circular dichroism spectroscopy. DFT calculations revealed a left‐handed helical structure for this polymer. This is the first evidence for a polyferrocene with a chiral secondary structure. [ABSTRACT FROM AUTHOR]

Ancient people's choices of where to live were strongly influenced by geography, especially by terrain. However, most settlement clustering algorithms, which use the Euclidean distance, do not consider terrain. Here, we present an improved clustering algorithm for the cluster analysis of ancient ruins that takes terrain‐related factors, such as slope and elevation, into account and uses the resistance distance (also known as the cost‐weighted distance) instead of the Euclidean distance. Furthermore, we select the prehistoric settlements (during 7‐3 ka BP within four cultural stages) in the Linfen area in the Fen River Basin as research objects to analyze the settlement distribution and spatiotemporal evolution of the four cultural staging sites with reference to the climate. We conclude that the proposed site clustering method based on terrain constraints can simulate ancient people's travel routes and improve the clustering results. The spatiotemporal analysis of prehistoric settlements in the Linfen area reveals that most of the settlements are distributed in the alluvial region of the river. Over time, the dependence on the rivers gradually decreased. The clustering and spatiotemporal analysis results show that the proposed method is feasible and applicable to ancient settlements. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present study was to investigate age‐specific normative retinal oxygen saturation values and explore the associated factors in healthy Chinese school‐aged children with different refractive statuses. Design: Population‐based observational cross‐sectional study. Methods: Children aged 7–19 years were enrolled. Each participant underwent a series of comprehensive ocular examinations, including axial length (AL), cycloplegic refraction and Oxymap T1 imagery following cycloplegia. The acquired oximetry images were measured, and the values of the retinal oxygen saturation parameters were calculated. The independent factors of the retinal oxygen saturation were analysed using multiple linear regression. The oxygen saturation of retinal arteries (SaO2) and veins (SvO2) as well as the differences between the arteries and veins (AVD) were measured as the main outcomes. Results: In total, 1461 participants were included in the study. The mean age of the participants was 12.1 ± 3.2 years, and 53.0% were boys. The mean SaO2, SvO2 and AVD values were 83.7 ± 6.4%, 50.1 ± 5.4% and 33.6 ± 5.4%, respectively, and the values increased with age. Girls had higher SvO2 and lower AVD than boys (p < 0.05). The Pearson correlation coefficients among spherical equivalent (SE) and SaO2, SvO2 and AVD were −0.372, −0.203 and −0.240, respectively (all p < 0.001), while the correlations between AL and SaO2, SvO2 and AVD were 0.276, 0.106 and 0.221, respectively (all p < 0.001). The myopia group had significantly higher SaO2, SvO2 and AVD than the emmetropia and hyperopia groups (p < 0.001), but the high myopia group had lower SaO2 and SvO2 than the moderate myopia group. When age, gender, body mass index (BMI), intraocular pressure (IOP) and axial length (AL) were included as factors in the multiple regression, older age was associated with higher SaO2, SvO2 and AVD, while longer AL was associated with higher SaO2 and AVD. Gender was an independent factor predicting SvO2, while gender and BMI were the independent factors predicting AVD. Age explained more variance than AL in SaO2, SvO2 and AVD. Conclusions: Our population‐based study provides age‐specific profiles of retinal oxygen saturation in Chinese children and adolescents. Older age and longer AL were important independent factors of increased retinal oxygen saturation. [ABSTRACT FROM AUTHOR]

Purpose: To explore the subfoveal thickness of sclera (SST), choroid (SCT) and retina (SRT) as well as their relationship in healthy Chinese children with varying levels of refractive error. Methods: A total of 810 healthy Chinese schoolchildren and adolescents underwent a series of comprehensive ocular examinations, as well as swept‐source optical coherence tomography (OCT) after induced cycloplegia. The thicknesses of the sclera, choroid and retina below the central fovea were measured manually, and each measurement was compared across different refractive statuses. Independent factors associated with the thickness of each layer were analysed. Results: The mean SST, SCT and SRT were 524 ± 57 μm, 195 ± 49 μm and 224 ± 19 μm, respectively. The SSTs and SCTs of myopes were significantly thinner than those of emmetropes and hyperopes (all p < 0.001). Although the choroid seemed to be thicker in hyperopes (225 ± 46 μm) than in emmetropes (211 ± 45 μm), no statistically significant difference was observed between emmetropes and hyperopes in the sclera and choroid. Thinner SSTs and SCTs were associated with greater levels of myopia, whereas the SRT was similar in children with different myopic levels. SST (p < 0.001) and SCT (p = 0.003) as well as age (p < 0.001), sex (p < 0.001) and axial length (p < 0.001) were independently associated with spherical equivalent refraction (SER). Older age (p = 0.013), myopic‐shifted SER (p < 0.001), thicker SCT (p < 0.001) and thinner SRT (p = 0.012) were independently associated with a thinner SST. Conclusion: The subfoveal sclera and choroid were thinner in myopes than in emmetropes and hyperopes, while the retina remains constant. Age, refractive error and choroidal and retinal thicknesses are related to subfoveal scleral thickness. [ABSTRACT FROM AUTHOR]

Importance Myopia is a major public health concern worldwide, while outdoor time is indicated to be protective against the onset of myopia. Background: To describe the methodology and baseline data of the Shanghai Time Outside to Reduce Myopia (STORM) trial. Design A 2‐year, school‐based, prospective, cluster randomized trial. Participants: Children from grade I and II classes of 24 schools from eight districts in Shanghai, China, were randomized to either a control group, a test group I (40‐min outdoor time/day) or test group II (80‐min outdoor time/day). Methods: At baseline and annual intervals, cycloplegic autorefraction and axial length measurement will be performed. Time outdoors and light exposure will be monitored via parent/carer questionnaires and a wearable device. Main Outcome Measures: Spherical equivalent, prevalence of myopia and time outdoors in each group. Results: A total of 6295 eligible children (age 7.2 ± 0.7 y [6‐9 y]) were randomized to control (n = 2037), test group I (n = 2329) and test group II (n = 1929). At baseline, spherical equivalent was +0.98 ± 1.02D, +1.02 ± 1.02D and +1.00 ± 0.99D (P = 0.708), myopia prevalence was 8.9, 7.7 and 7.8% (P = 0.270) and time outdoors was 58.5 ± 35.8, 59.8 ± 34.7 and 58.5 ± 35.3 min/d (P = 0.886) for control, test groups I and II, respectively. Conclusions and Relevance: Myopia prevalence was high at nearly 8 to 9% in school children aged 7 years in Shanghai, China. The current trial will help evaluate if increased time outdoors has a role to play in reducing the incidence of myopia and/or slow the progression of myopia. [ABSTRACT FROM AUTHOR]

Objective: Multislice computed tomography (MSCT) has been used for diagnosis of small intestinal diseases. However, the radiation dose is a big problem. This study was to investigate whether CARE Dose 4D combined with sinogram‐affirmed iterative reconstruction (SAFIRE) can provide better image quality at a lower dose for imaging small intestinal diseases compared to MSCT. Methods: The noise reduction ability of SAFIRE was assessed by scanning the plain water mold using SOMATOM Definition Flash double‐source spiral CT. CT images at each stage of radiography for 239 patients were obtained. The patients were divided into groups A and B were based on different tube voltage and current or the image recombination methods. The images were restructured using with filtered back projection (FBP) and SAFIRE (S1–S5). The contrast noise ratio (CNR), CT Dose index (CTDI), subjective scoring, and objective scoring were compared to obtain the best image and reformation parameters at different stages of CT. Results: Twenty‐six restructuring patterns of tube voltage and current were obtained by FBP and SAFIRE. The average radiation dose using CARE Dose 4D combined with SAFIRE (S4–S5) reduced approximately 74.85% compared to conditions where the tube voltage of 100 kV and tube current of 131 mAs for patients with MSCT small intestinal CT enterography at plain CT scan, arterial stage, small intestine, and portal venous phase. The objective and subjective scoring were all significantly different among groups A and B at each stage. Conclusions: Combination of CARE Dose 4D and SAFIRE is shown to decrease the radiation dose while maintaining image quality. [ABSTRACT FROM AUTHOR]

Importance Cohort studies could not only reveal associations between change of refractive components and onset/progression of myopia, but also risk factors, which is important for understanding mechanism and providing strategies. Background: Prevalence of myopia is high in Shanghai, being reported to be 52.2% in children aged 10 years old. Design Cohort study. Participants: A total of 1856 students from six randomly selected primary schools in Baoshan District, Shanghai. Methods: Children underwent comprehensive ocular measurement, including axial length (AL), corneal curvature radius and cycloplegic auto‐refraction. Questionnaires about eye usage time were collected. Grade 1 students were followed for 4 years, and grade 2 and 3 students for 2 years. Main Outcome Measures: (i) Change of spherical equivalent (SE) and AL and (ii) risk factors for progression and incidence of myopia. Results: The average 2‐year progress of SE was 0.91D, 0.91D and 1.11D for grade 1, 2 and 3, respectively, and the average elongation of AL was 0.70 mm, 0.64 mm and 0.71 mm, respectively. Only parental myopia, but not near work time, near work diopter time, outdoor activity time or attending tutoring classes, was associated with myopia incidence and progression in the present population. Using baseline SE could be a simple and effective indicator for myopia prediction. Conclusions and Relevance: Incidence and progression of myopia is relatively high in schoolchildren in Shanghai compared with children of Western countries, East Asia and other parts of China. Effective strategies to control myopia prevalence are in urgent need. [ABSTRACT FROM AUTHOR]

Abstract: Three enantiopure phospha[1]ferrocenophanes (2R) equipped with either a phenyl, an isopropyl, or a tert‐butyl group at the bridging phosphorus atom were synthesized by a salt‐metathesis approach in isolated yields between 52 and 63 %. The chirality in these strained sandwich compounds stems from the planar‐chiral ferrocene moiety, which is symmetrically equipped with two iPr groups adjacent to phosphorus. Surprisingly, all three phospha[1]ferrocenophanes show an uncommon through‐space nuclear 1H–31P coupling. As a result of the embedded symmetry, these new compounds are ideal examples to differentiate between through‐space and through‐bond coupling mechanisms in NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: Importance: Nearly half of children suffering vision impairment reside in China with myopia accounting for the vast majority. Background: To describe the design and methodology of the Shanghai Child and Adolescent Large‐scale Eye Study (SCALE). Design: The SCALE was a city wide, school‐based, prospective survey. Participants: Children and adolescents aged 4–14 years from kindergarten (middle and senior), primary schools and junior high schools of all 17 districts and counties of the city of Shanghai, China were examined in 2012–2013. Methods: Each enrolled child underwent vision assessment (distance visual acuity; uncorrected and with corrective device if worn) and their parent/carer completed a questionnaire designed to elicit risk factors associated with myopia. Additionally, non‐cycloplegic autorefraction and ocular axial length was measured in a subset of the larger sample. Main Outcome Measures: Prevalence and the associated factors of vision impairment, myopia and high myopia in Shanghai. Results: In 2012–2013, a total of 910 245 of the eligible 1 196 763 children and adolescents identified from census (76%, mean age 9.0 ± 2.7 years [4–14 years]) were enrolled with visual acuity screened in the city of Shanghai. Of these, 610 952 children (67% of the entire sample) underwent non‐cycloplegic autorefraction and 219 188 (24% of the entire sample) had both non‐cycloplegic autorefraction and axial length measurements. Conclusions and Relevance: The study results will provide insights on the burden of vision impairment, myopia and high myopia in children and adolescents in a metropolitan area of China, and contribute to the policies and strategies to address and limit the burden. [ABSTRACT FROM AUTHOR]

A wideband circularly polarized (CP) 2-arm spiral antenna is designed for 60-GHz applications in this letter. The proposed antenna is implemented on a single layer with spiral printed on the top surface of the substrate and fed in a differential way through 2 metallized via holes. Unidirectional radiation is achieved thanks to the presence of the ground plane, which is placed with a distance of one-quarter of the guided wavelength to the spiral. A cavity is mounted on the top of the spiral antenna to suppress the surface wave propagate along the substrate as well as to improve the antenna gain. Experimental results show that the prototype achieves the −10-dB impedance bandwidth from 55.2 to 66 GHz with circular polarization. The peak gain at boresight is 9.5 dBi occurring at 63 GHz and the radiation patterns are stable over the operating frequency band. [ABSTRACT FROM AUTHOR]

Purpose To systematically analyse the differences between cycloplegic and noncycloplegic refractive errors ( RE) in children and to determine if the predictive value of noncycloplegic RE in categorizing RE can be improved. Methods Random cluster sampling was used to select 6825 children aged 4-15 years. Autorefraction was performed under both noncycloplegic and cycloplegic (induced with 1% cyclopentolate drops) conditions. Paired differences between noncycloplegic and cycloplegic spherical equivalent ( SE) RE were determined. A general linear model was developed to determine whether cycloplegic SE can be predicted using noncycloplegic SE, age and uncorrected visual acuity ( UCVA). Results Compared to cycloplegia, noncycloplegia resulted in a more myopic SE (paired difference: −0.63 ± 0.65D, 95% CI: −0.612 to −0.65D, 6017 eligible right eyes) with greater differences observed in younger participants and in eyes with more hyperopic RE and smaller AL. Using raw noncycloplegic data resulted in only 61% of the eyes being correctly classified as myopic, emmetropic or hyperopic. Using age and uncorrected VA in the model, the association improved and 77% of the eyes were classified correctly. However, predicted cycloplegic SE continued to show large residual errors for low myopic to hyperopic RE. Applying the model to only those eyes with uncorrected VA <6/6 resulted in an improvement ( R2 = 0. 93), with 80% of the eyes correctly classified. A higher VA cut-off (i.e., ≤6/18) resulted in 97.5% of eyes classified correctly. Conclusion Noncycloplegic assessment of RE in children overestimates myopia and results in a high error rate for emmetropic and hyperopic RE. Adjusting for age and applying uncorrected VA cut-offs to noncycloplegic assessments improves detection of myopic RE and may help in identifying myopic RE in situations where cycloplegia is not available but does not help in identifying the magnitude of refractive error and therefore is of limited value. [ABSTRACT FROM AUTHOR]

Outdoor time is considered to reduce the risk of developing myopia. The purpose is to evaluate the evidence for association between time outdoors and (1) risk of onset of myopia (incident/prevalent myopia); (2) risk of a myopic shift in refractive error and c) risk of progression in myopes only. A systematic review followed by a meta-analysis and a dose-response analysis of relevant evidence from literature was conducted. PubMed, EMBASE and the Cochrane Library were searched for relevant papers. Of the 51 articles with relevant data, 25 were included in the meta-analysis and dose-response analysis. Twenty-three of the 25 articles involved children. Risk ratio ( RR) for binary variables and weighted mean difference ( WMD) for continuous variables were conducted. Mantel-Haenszel random-effects model was used to pool the data for meta-analysis. Statistical heterogeneity was assessed using the I2 test with I2 ≥ 50% considered to indicate high heterogeneity. Additionally, subgroup analyses (based on participant's age, prevalence of myopia and study type) and sensitivity analyses were conducted. A significant protective effect of outdoor time was found for incident myopia (clinical trials: risk ratio ( RR) = 0.536, 95% confidence interval ( CI) = 0.338 to 0.850; longitudinal cohort studies: RR = 0.574, 95% CI = 0.395 to 0.834) and prevalent myopia (cross-sectional studies: OR = 0.964, 95% CI = 0.945 to 0.982). With dose-response analysis, an inverse nonlinear relationship was found with increased time outdoors reducing the risk of incident myopia. Also, pooled results from clinical trials indicated that when outdoor time was used as an intervention, there was a reduced myopic shift of −0.30 D (in both myopes and nonmyopes) compared with the control group ( WMD = −0.30, 95% CI = −0.18 to −0.41) after 3 years of follow-up. However, when only myopes were considered, dose-response analysis did not find a relationship between time outdoors and myopic progression ( R2 = 0.00064). Increased time outdoors is effective in preventing the onset of myopia as well as in slowing the myopic shift in refractive error. But paradoxically, outdoor time was not effective in slowing progression in eyes that were already myopic. Further studies evaluating effect of outdoor in various doses and objective measurements of time outdoors may help improve our understanding of the role played by outdoors in onset and management of myopia. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a tri-band multiple-input-multiple-output (MIMO) mobile antenna for WWAN and LTE applications. The tri-band antenna element consists of a planar inverted-F antenna (PIFA) which is coupled-fed by an L-shaped driven strip monopole. Long parallel folded strip (PFS) printed adjacent to the upper edge of PIFA is used to generate an additional mode in the lower band, making the antenna capable of covering the whole GSM850 and GSM900 bands. Two n-shaped strips are placed between the antenna elements to improve port isolation. The proposed antenna exhibits triple bands including the lower band of 0.81-0.97 GHz, the middle band of 1.36-2.80 GHz, and the upper band of 3.40-3.75 GHz for WWAN and LTE applications. Detailed geometry and working mechanisms of the antenna are presented. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1446-1450, 2017 [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, a coupled-fed tri-band multiple-input-multiple-output (MIMO) mobile antenna is proposed for WWAN and LTE applications. The MIMO antenna system is composed of two antenna elements and they are oriented diagonally at the non-grounded portion of the FR-4 substrate. Each antenna element consists of a planar inverted-F antenna (PIFA) coupled-fed by a L-shaped driven strip monopole. By adding a parallel-resonant spiral slit in the main ground, the bandwidth of the lower band can be enhanced to cover the whole GSM850 and GSM900 bands without increasing the antenna size. Slits embedded on the ground are employed to enhance port isolation between the antenna elements. The proposed antenna provides triple bands including the lower band of 810-965 MHz, middle band of 1560-3320 MHz, and upper band of 3400-3590 MHz for WWAN and LTE applications. Detailed geometry and working mechanisms of the antenna are presented. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:463-468, 2017 [ABSTRACT FROM AUTHOR]

A mixture of cis/ trans isomers of phospha[1]ferrocenophanes equipped with one iPr group at the α position to the bridging PhP moiety was prepared. Both isomers ( cis- 4 and trans- 4) were obtained as racemates and could be separated so that their thermal properties were investigated individually. The molecular structure of cis- 4 was determined by single-crystal X-ray analysis showing a tilt angle α=26.35(8)°. Interconversion between both isomers occurred in the melt at elevated temperatures and revealed that the trans isomer is thermodynamically more stable. Structural and thermodynamic data was complemented by DFT calculations (B3PW91/6-311+G(d,p) and B3PW91-D3(BJ)/6-311+G(d,p)). Performance of thermal ring-opening polymerization (ROP) of trans- 4 at 230 °C gave polymers and cyclic oligomers. Gel permeation chromatography (GPC) of the sulfurized polymer resulted in a molecular weight of 62.5 kDa ( Mw) and a polydispersity index of 1.39 (PDI). Mass spectrometric analysis of the oligomers showed the presence of cyclic species from dimers to heptamers. After sulfurization, preparative thin layer chromatography led to the separation of three isomeric dimers. Structural characterization of these dimers by single-crystal X-ray analysis led to the conclusion that the Fe−Cp bond breaks during the thermal ROP process. A mechanism similar to the known mechanism of the photolytic ROP of ferrocenophanes is proposed. [ABSTRACT FROM AUTHOR]

A wideband bandpass filter based on dual-mode defected ground structure resonator (DGSR) is designed and effectively analysed by utilising the even-/odd-mode theory and equivalent circuit models. The lower and upper cutoff frequencies of the filter can be independently tuned by adjusing the even- and odd-mode resonant frequencies of the dual-mode DGSR, respectively. The fabricated prototype is centred at 2.27 GHz with a wide bandwidth (FBW 63.4%), low insertion loss (0.386 dB), high selectivity and wide stopband. The attenuation slopes in the lower and upper passband transitions are 108.5 and 136.9 dB/GHz, respectively. The stopband rejection is better than 22 dB up to 6 GHz (2.6 f0). © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2300-2303, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT To address the metallic interference problem in vehicular RFID (radio-frequency identification) applications, this letter proposes a novel alumina ceramic slot tag antenna (ACSTA). The proposed antenna consists of a grounded thin alumina ceramic substrate and a slotted top layer rectangular patch, and the all four sides of the substrate are shorting walls. The slot can be equivalent to a horizontal magnetic current flow, so an excellent radiation performance is achieved according to the electromagnetic image theory. Meanwhile, due to the existence of the ground plane, the influences of metallic objects behind the ground to the tag antenna impedance can be maximally reduced. Combined with a commercial chip, this ACSTA is fabricated and measured, and the thickness of the novel tag is only 1mm. The tag antenna offers a half power coefficient bandwidth of 6.9% (0.87-0.93 GHz) with a stable gain about 3.6 dBi, and a similar half power coefficient bandwidth of 6.9% (0.89-0.95 GHz) with a gain about 4.8 dBi when it is attached to an 100 × 100 mm2 metallic plate, respectively. Moreover, the experimental results show that the maximum read range is about 27 or 30 m without or with a same attached 100 × 100 mm2 metallic plate, respectively. Simulation and measurement results show that the operating frequency band of the ACSTA covers US legal UHF RFID (902-928 MHz) band, and so it is a quite suitable candidate for vehicular RFID applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1150-1154, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT A compact coplanar waveguide (CPW) fed ultrawideband (UWB) slot antenna for multiple-input-multiple-output (MIMO)/diversity applications is presented in this letter. The antenna consists of two coplanar waveguides (CPWs) feeding circular radiating elements and a protruded stub, which is placed at between them. The circular radiating elements are arrange orthogonally and fed perpendicularly to obtain polarization diversity. Notched band at X-band communication downlinks is achieved by etching split ring resonator slots in the radiators and the other notched band at WLAN system is achieved by the collaboration of arc-shaped strips and the protruded stub. The protruded stub not only can help to achieve band rejection but also can reduce mutual coupling between two ports. As all of the structures are printed in one layer, it can be very easily to be integrated with RF front-end circuits. Simulated and measured results show that the proposed antenna meets the 10-dB impedance bandwidth from 3.4 to 12 GHz and isolation better than 15 dB at most of the band. Good diversity performance in terms of envelope correlation coefficient and the ratio of mean effective gain demonstrates that the antenna is quite suitable for MIMO UWB applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:989-994, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT In this letter, a compact ultrawideband polarization diversity MIMO antenna system with dual band-notched characteristics is proposed. The proposed antenna element consists of a metal ground with a stepped slot etched on it. The stepped slot is fed by a 50-Ω microstrip line on the top layer. Dual notched bands (5G WLAN and 8G X band) are achieved by etching an open ended slot and a split ring resonator in the ground plane, respectively. Two identical antenna elements are arranged orthogonally and fed perpendicularly to obtain polarization diversity and enhance port isolation. A simple Y-shaped defected ground structure is etched in the ground plane to suppress mutual coupling between two antennas and improve the impedance matching. Diversity performance in term of envelop correlation coefficient (ECC) and mean effective gain (MEG) are studied. The simulated and measured results show good agreement, which demonstrates that the proposed MIMO antenna system can be a good candidate for UWB MIMO system applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:626-630, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT The 6-amino-6-deoxychitosan (NC) and their 2, 6-di-N-sulfonated derivatives were prepared via N-phthaloylation, tosylation, azidation, hydrazinolysis, reduction of azide groups and N-sulfonation, and their structures were systematically characterized by FT-IR, 2D HSQC NMR, XRD, gel permeation chromatography (GPC), and elemental analysis. The 6-amino-6-deoxychitosan showed effect in three selected antioxidant essays, including reducing power, superoxide anion radical scavenging ability, and hydroxyl radical scavenging effect. But the factors affecting each activity were different. The reducing power and the superoxide anion radical scavenging ability of NC were strong and closely related to the amino groups in the molecular chains. Both introducing N-sulfonated groups into NC and the concentration reduction of NC and its sulfonated derivatives decreased these activities. For the superoxide anion radical, the molecular charge property was also a significant influence factor. For the hydroxyl radical, NC only showed weak scavenging activity in a special inverse concentration-dependent manner. However, the incorporation of N-sulfonated groups significantly improved the scavenging activity, and the more N-sulfonated groups, the higher the concentrations, the stronger the activity was. The results could be due to the different conformations of NC and its sulfonated derivatives in aqueous solution. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 539-549, 2015. [ABSTRACT FROM AUTHOR]

Biaxial thermotropic nematic liquid crystals would be of great importance in liquid crystal display technology. Less than a decade ago, such liquid crystals were suggested. The biaxiality of the phases was confirmed using 2H NMR spectroscopy of deuterated probe molecules. The spectra were collected from a sample rotating around an axis perpendicular to the external magnetic field, resulting in a two-dimensional powder pattern. We have proposed an alternate technique that is based on the second order quadrupole shift detectable in 131Xe NMR spectra of dissolved xenon. The method has many advantages, such as the NMR spectra are taken from a static sample and the 131Xe quadrupole coupling tensor is extremely sensitive to the symmetry of the phase. In the present study, we report results obtained on a 600-MHz NMR spectrometer. Together with the data of our earlier study, they confirm that the asymmetry parameter of the 131Xe quadrupole coupling tensor in the nematic phase of a ferroelectric liquid crystal is 0.85 and in the smectic A phase ca 0.62, indicating significant phase biaxiality. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Solid solution composites of ( Ti, V)2 AlC/ Al2 O3 were successfully synthesized using the in situ hot-pressing process by the incorporation of the thermit reaction of Al with V2 O5 in Ti, Al, and carbon black system. The phase evolution during the formation of the composites was examined from 500°C to 1350°C, and a possible reaction mechanism was proposed to explain the formation of ( Ti, V)2 AlC/ Al2 O3 solid solution composites. The composite with 10 wt% Al2 O3 possesses the best mechanical properties and the hardness, flexural strength, and fracture toughness of the composites are enhanced by 53.2%, 140%, and 180%, respectively. The strengthening and toughening mechanisms were also discussed. [ABSTRACT FROM AUTHOR]

The article presents information on a study which described the fabrication of a low-loss flexible magnetic composite with Ni0.8Zn0.2Fe2O4 (NZO) ultrafine particles embedded in a thermoplastic polyolefin elastomer matrix via extrusion technology. Also investigated were the electromagnetic and mechanical properties of the as-prepared composites. The effect of increasing ceramic fillers on the permittivity and permeability of the composite is described.

Frontispiz: Unique Bora[1]ferrocenophanes with Sterically Protected Boron: A Potential Gateway to Helical Polyferrocenes Keywords: Boron; Chiralität; Gespannte Moleküle; Helikale Strukturen; Ringöffnende Polymerisation Boron, Chiralität, Gespannte Moleküle, Helikale Strukturen, Ringöffnende Polymerisation. [Extracted from the article]

Surfaces and Interphase: Synergistic Strengthening and Toughening the Interphase of Composites by Constructing Alternating "Rigid-and-Soft" Structure on Carbon Fiber Surface (Adv. Keywords: carbon fibers; interface/interphase; polymer-matrix composites; surface treatments Carbon fibers, interface/interphase, polymer-matrix composites, surface treatments. [Extracted from the article]

Interphase with nacre‐like structured multilayer is constructed by alternatively depositing two polymers, respectively "rigid" polydopamine (PDA) and "flexible" polyether amine, on carbon fiber surface via the layer‐by‐layer (LbL) approach. The optimal interfacial strength and toughness are achieved for composites with three layers of PDA/polyether amine, respectively, 39.2% and 99.8% superior to the untreated fiber composites. The outstanding mechanical properties are mainly ascribed to the synergistic interactions of covalent bond, hydrogen bonding, and π–π stacking among fiber, multilayer, and matrix by transferring stress and bridging cracks, as well as the alternating "rigid and flexible" structure of interphase by deflecting crack path and inducing plastic deformation and viscoplastic energy dissipation. This work opens a new, feasible, and easy scalable avenue for constructing integrated high‐performance fiber composites. [ABSTRACT FROM AUTHOR]

Yangshao culture, as the most important Neolithic culture in China, is famous for its finely decorated pottery. In this work, Yangshao potteries excavated in Shanxi province, one of the core distribution areas, were studied by micro‐Raman spectroscopy combined with optical microscopy, X‐ray fluorescence, and scanning electron microscopy equipped with energy‐dispersive X‐ray spectroscopy. The color of the red decor is derived from hematite and maghemite. The black decorations on the surface are more complex, which could be divided into two types according to the Mn/Fe ratios and crystalline types: (1) low MnO2/Fe2O3 ratio and jacobsite and magnetite and (2) high MnO2/Fe2O3 ratio and hausmannite. The former color is obviously brighter than the latter. This study also demonstrates the potential of micro‐Raman microscopy in analyzing the nature of colorant crystals in Yangshao painted potteries and, therefore, better deciphering the technical details involved in the potteries of Yangshao culture. [ABSTRACT FROM AUTHOR]

Small‐size pixels and high efficiency under low injection levels are required for high‐resolution microdisplay. Efficient blue InGaN micro‐light‐emitting diodes (μLEDs) with 5 μm diameter are fabricated using AuSn flip‐chip bonding, high reflection electrodes, and large‐area N electrodes surrounding the mesas. The peak external quantum efficiency (EQE) measured in an integrating sphere is as high as 13.67% at a current density of 5.4 A cm−2. Moreover, at a current density of 0.1 A cm−2, EQE can still reach 11.69%. The electrical efficiency approaches 1, and the differential slope of log L versus log I is close to 1 at low current density. These results suggest significant progress in exploring high‐efficiency 5 μm InGaN blue μLEDs. [ABSTRACT FROM AUTHOR]