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Beam scanning based on metasurfaces is widely discussed in recent years owing to its high integration, lightweight, and low cost. However, most of the reported beam scanning metasurfaces operate in either transmission or reflection mode. Here, we propose a full-space beam scanning metasurface based on transmission reflection switchable meta-atom and the quadratic phase distribution. As a validation, a metasurface array with 400 units (20 × 20) was experimentally demonstrated. Beam scanning of ± 35 ° was achieved in both transmission mode and reflection mode. A larger scanning angle (± 45 °) was further verified simulatively with a 900-units (30 × 30) array. The method provides an avenue for expanding the space of electromagnetic wave manipulation and may have great potential in wireless communication and radar detection.

A broadband, electrically controlled, reconfigurable, circularly polarized reflective metasurface is presented. The chirality of the metasurface structure is changed by switching active elements, which benefits from the tunable current distributions generated by the elaborately designed structure under x-polarized and y-polarized waves. Notably, the proposed metasurface unit cell maintains a good circular-polarization efficiency in a broadband range of 6.82-9.96 GHz (fractional bandwidth of 37%) with a phase difference of π between the two states. As a demonstration, a reconfigurable circularly polarized metasurface containing 8 × 8 elements was simulated and measured. The results verify that the proposed metasurface can flexibly control circularly polarized waves in a broadband, realizing beam splitting, mirror reflection, and other beam manipulations from 7.4 GHz to 9.9 GHz (fractional bandwidth of 28.9%) by simply adjusting the loaded active elements. The proposed reconfigurable metasurface may offer a promising approach to electromagnetic wave manipulation or communication systems.

We propose a dual-band achromatic focusing metasurface based on polarization multiplexing and dispersion engineering. An anisotropic resonant phase meta-atom is designed to realize independent nonlinear phase manipulation along the orthogonal directions. Achromatic focusing metasurface and broadband reflectarray antenna are further constructed in the microwave region with a computer-assisted particle swarm optimization algorithm. The standard deviation of focus offset at 11-16 GHz (for x-polarization) and 18-24 GHz (for y-polarization) are compressed to 19.83% and 16.60% of the dispersive metasurface, respectively. The radiation gains of the reflectarray antenna increase by an average of 19.49 dB and 15.08 dB in the broadband region compared with the bare standard rectangle waveguides. Furthermore, such an achromatic metasurface can be utilized to realize different functions with polarization selectivity and applied to other frequency ranges, which holds great promise in integrated optics.

Summary Although tremendous efforts have been devoted to investigating the analogy between the surface plasmon polariton and its spoof counterparts, it remains elusive that a single thin spoof plasmonic metalens realizes wide-angle focusing and wide field-of-view (FOV) imaging. Here, we propose a spoof plasmonic metasurface that can impart arbitrary phase with high transmittance, which comprises two-dimensional (2D) gradient spoof-insulator-spoof waveguides. With the developed catenary field and dispersion theory, their intrinsic physics is theoretically analyzed. As a proof of concept, a spoof plasmonic metalens with a thickness of 0.15λ has been elaborately designed and experimentally demonstrated for wide-angle (∼170°) focusing and wide FOV (∼40°) imaging. To the best of our knowledge, it is the first experimental demonstration of wide FOV imaging of a 2D object with single thin and planar metalens in the microwave regime. The proposed method offers a promising solution to compact cameras, integrated imaging, and detection systems., Graphical Abstract, Highlights • Thin spoof metalens has been developed • A satisfactory qualitative description through catenary dispersion theory • Wide-angle microwave focusing (170°) and wide FOV (40°) imaging of 2D objects, Optical Imaging; Electromagnetic Waves; Surface

Amplitude, phase, and polarization are three fundamental properties of electromagnetic (EM) waves, while the simultaneous control by conventional materials are usually associated with heavy and bul...

Optical vortices (OVs) created from helical modes of light have extensive applications in optical manipulation, imaging, and optical communications. Moreover, modulated optical vortices (MOVs) with modified wavefronts could provide new opportunities for fractionating particles and actuating microelectromechanical systems. Traditional devices for generating MOVs include spatial light modulators, spiral phase plates, and so on. However, such bulky devices are difficult to be applied to high-level integrated optical systems. Besides, other MOV generators are typically static and polarization-insensitive. Here, we proposed an all-dielectric metasurface to generate polarization-sensitive MOVs. The intensity patterns of the OVs can be modulated by adding a tangential modulation factor in the phase profile. Independent manipulation of two orthogonal polarizations was adopted via tailoring the geometric parameters of silicon (Si) pillars. We experimentally demonstrated that the metasurface could generate a doughn...

Reconfigurable metasurfaces have attracted a deal of attention owing to their multifunctional and dynamic electromagnetic (EM) manipulation properties. However, most of the previous reconfigurable metasurfaces rely on manual control for function switching, which has huge limitations in practical application. Here, an intelligent metasurface with the self-adaptively EM manipulation capability is proposed. It integrates the sensing-and-feedback components to construct a closed-loop system, which can automatically adjust EM functionalities for the different incident power information. The sensing module in this metasurface can first perceive the incident EM power intensity and then provide the feedback signal to the field programmable gate array controlling platform that can send the corresponding instruction to the executing material for switching the EM functionality among transmission, reflection, and tunable absorption. Good self-adaptive reaction capability and practicability of the proposed metasurface have been demonstrated by the experiment. It has the capability of making a real-time response with adaptive EM behavior to the varying incoming wave power without the aid of human beings. Our design provides an avenue toward intelligent and cognitive metasurfaces, which has extensive application prospects in smart skin, intelligent absorber, and the related EM fields.

Summary Recently, metasurface-based multichannel optical vortex arrays have attracted considerable interests due to its promising applications in high-dimensional information storage and high-secure information encryption. In addition to the well-known wavelength and polarization multiplexing technologies, the diffraction angle of light is an alternative typical physical dimension for multichannel optical vortex arrays. In this paper, based on angular multiplexing, we propose and demonstrate multichannel optical vortex arrays by using ultrathin geometric metasurface. For a circularly polarized incident light, the desired optical vortex arrays are successfully constructed in different diffraction regions. Moreover, the diffraction angle of the optical vortex array can be regulated by changing the illumination angle of incident light. Capitalizing on this advantage, the angular-multiplexed recombination of optical vortex array is further investigated. The combination of the diffraction angle of light and optical vortex array may have significant potential in applications of optical display, free-space optical communication, and optical manipulation., Graphical Abstract, Highlights • Ultra-thin angular-multiplexed multichannel vortex array generators are demonstrated • Geometric phase is employed to realize the desired phase profiles • Generation of various multichannel vortex arrays and recombination of vortex array, Optics; Optical Materials; Geometrical Optics; Metamaterials

Metasurfaces used in the manipulation of light beams have attracted growing interests owing to their unique electromagnetic properties in the subwavelength regime. However, most previously demonstrated single-layer metasurfaces are normally designed to realize one-fold function of either polarization or phase manipulation and suffer from low cross-polarization conversion efficiency and high-background, especially for transmissive metasurfaces. Here, a metasurface based on metal-insulator-metal (MIM) subwavelength grating is proposed to simultaneously achieve polarization filtering and phase controlling. The transmission coefficient reaches up to 78.9% and the polarization extinction ratio (ER = 20*log(T TM /T TE) is larger than 16.1 dB. A local abrupt phase difference covering 0–2π is introduced into transmitted light with the polarization direction vertical to the grating by artificially tailoring the geometrical parameters of MIM grating. Furthermore, background-free wavefront control and high-purity radial/azimuthal polarization are realized by the metasurfaces based on the MIM grating. This flexible and high-efficient scheme of full control wavefront and polarization promises an unprecedented progress of spatial vectorial beams modulation and enable the realization of novel optical components.

Simultaneous manipulation of light polarization and phase possesses great significance for modern optical technologies. Here we propose metal-dielectric gratings capable of tailoring the polarization and phase of light based on polarization filtering with the polarization extinction ratio exceeding 10 dB and the transmittance higher than 65%. The standard radially polarized (RP) light with axially symmetric polarization distribution can be generated by using arrayed grating with gradient phase under the illumination of circularly polarized (CP) light. Besides, a RP metasurface lens with high numerical aperture is presented, which can convert the CP light into the focused radially polarized light at wavelength of 632.8 nm. This compact and efficient approach would have potential applications in beam manipulation, super-resolution imaging and integrated optics system.

Background Osteosarcoma is a most common bone malignant tumor which threatens children and adolescents. Circular RNAs (circRNAs) fundamentally play essential roles in the progress and development of human cancers by sponging with microRNAs (miRNAs). However, the role of circRNAs in osteosarcoma is not clear. The aim of the study was to investigate the roles and molecular mechanism of circRNAs in osteosarcoma. Results The data from qRT-PCR showed that circ_0051079 expression was higher in osteosarcoma cells and tissues compared to their normal controls. Meanwhile, bioinformatic analysis indicated that circ_0051079 was a sponge of miR-26a-5p, which was verified by luciferase activity assay. Subsequently, TGF-β1 was verified as a putative target mRNA of miR-26a-5p by luciferase assay. Cellular function assays were conducted and the findings revealed that circ_0051079/miR-26a-5p/TGF-β1 regulated osteosarcoma proliferation and metastasis. Conclusion The study demonstrated that circ_0051079 could act as an oncogene via regulating miR-26a-5p/TGF-β1 and a potential biomarker for osteosarcoma diagnose.

Additional file 1: Figure S1. a The microscopic images of migration assays. The migratory ability of U2OS and SaoS2 cells. U2OS and SaoS2 cells were transfected with circ_0051079 shRNA or miR-26a-5p mimics for 24 h and cell wound healing assay was performed and the photos were taken under a microscope. b The invasion ability of U2OS and SaoS2 cells. U2OS and SaoS2 cells were transfected with circ_0051079 shRNA or miR-26a-5p mimics for 24 h and the photos of invaded cells were taken under a microscope. Figure S2. The effects of Hsa_circ_0051079 knockdown or overexpression on the protein expression of TGFB1 and the activation of TGFB signaling. The total protein from U2OS and SaoS2 cells were extracted for western blotting. Figure S3. The correlation between Hsa_circ_0051079 and TGF-β1 in patients.

To summarize a new type of proximal humerus fracture-proximal humerus degloving fracture, and discuss its injury mechanism, classification criteria, and treatment methods.The clinical data of 23 patients with proximal humerus degloving fracture between September 2009 and September 2016 was retrospectively analyzed. There were 14 males and 9 females, with an average age of 39.7 years (range, 21-66 years). The causes of injury was sprain in 2 cases, falling from height in 8 cases, and traffic accident in 13 cases. The time from injury to operation was 3-116 days (mean, 17.1 days). There were 2 cases of posterior dislocation of humeral head, 3 cases of anterior dislocation of humeral head, 3 cases of other fractures, and 2 cases of brachial plexus injury. All patients had varying degrees of rotator cuff injuries. According to the self-determined fracture classification criteria, there were 6 cases of internal rotation type, 14 cases of external rotation type, and 3 cases of abduction type. All patients underwent open reduction and internal fixation.All patients were followed up 9-24 months (mean, 17 months). All incisions healed by the first intention. X-ray films showed that all fractures healed at 3-5 months after operation (mean, 3.6 months). According to the Neer's shoulder functional evaluation criteria at 6 months, the shoulder function was rated as excellent in 16 cases, good in 5 cases, fair in 1 case, and poor in 1 case, and the excellent and good rate was 84.6%. The rotator cuff tear recurred in 1 case and was repaired again.The injury mechanism of proximal humerus degloving fracture may be the extreme internal rotation, extreme external rotation, or extreme abduction. Reduction and internal fixation is an effective treatment. The focus of the treatment is not only the fixation of the fracture, but also the repair and reconstruction of the rotator cuff.总结一种新的肱骨近端骨折类型—肱骨近端脱套样骨折，并探讨其受伤机制、分型标准及治疗方法。.回顾分析 2009 年 9 月—2016 年 9 月收治的 23 例肱骨近端脱套样骨折患者临床资料。男 14 例，女 9 例；年龄 21～66 岁，平均 39.7 岁。致伤原因：扭伤 2 例，高处跌落伤 8 例，交通事故伤 13 例。受伤至手术时间 3～116 d，平均 17.1 d。肱骨头后脱位 2 例、前脱位 3 例，其他部位骨折 3 例，臂丛损伤 2 例；均伴肩袖不同程度挫伤。根据自定骨折分型标准：内旋型 6 例，外旋型 14 例，外展型 3 例。23 例均行切开复位内固定术。.23 例患者均获随访，随访时间 9～24 个月，平均 17 个月。切口均Ⅰ期愈合。X 线片复查示骨折均愈合，愈合时间 3～5 个月，平均 3.6 个月。术后 6 个月采用 Neer 标准进行肩关节功能评定：优 16 例、良 5 例、可 1 例、差 1 例，优良率 84.6%。术后 1 例发生肩袖再次撕裂，行二次手术修补。.肱骨近端脱套样骨折可能为肩关节受到暴力后极度内旋、外旋和外展所致，经复位内固定治疗可获得确切疗效。治疗时注意除骨折复位固定外，肩袖修复及功能重建也是治疗成功的关键。.

Circularly polarized (CP) thermal emission possesses huge application value in the fields of infrared detecting and polarimetric thermal imaging; however, the naturally occurring infrared source is incoherent and unpolarized. In this paper, we designed a broadband CP source adaptive for high temperature in consideration of the collision frequency of the electrons increasing with temperature. Compared with the structure proposed before, “I”-shaped resonators based on refractory plasmonic material generate the linearly polarized (LP) emission and the dielectric quarter-wave plate enhances the degree of emitted CP by suppressing the parasitic radiation. More than 80 % right-handed circularly polarized (RCP) emissivity in wavelengths ranging from 3.28 to 4.81 μm within 706 to 884 K is theoretically achieved.

We aim to uncover the methylation of microRNA-7 (miR-7) promoter in osteosarcoma (OS) and the inner mechanism of miR-7 on the progression of OS cells. Expression and methylation state of miR-7 in OS tissues and cells were detected. With the aim to unearth the ability of miR-7 in OS, the proliferation, cell cycle progression, apoptosis, invasion, migration of OS cells, and the tumor growth in nude mice were determined. Meanwhile, IGF1R expression was detected and the association between miR-7 and IGF1R was confirmed. The proliferating cell nuclear antigen (PCNA) expression was tested by immunohistochemical staining, and the lung metastasis was observed by H&E staining. miR-7 expression was decreased and methylation state of miR-7 was increased in OS tissues and cells. Upregulated miR-7 inhibited proliferation, cell cycle progression, invasion,and migration, while inducing apoptosis of OS cells and the tumor growth as well as PCNA expression in nude mice. Expression of IGF1R was downregulated in OS cells with overexpression of miR-7. Experiments verified the binding site between miR-7 and IGF1R. Our study demonstrates that abnormal methylation of miR-7 contributes to decreased miR-7 in OS. In addition, miR-7 represses the initiation and progression of OS cells through the inhibition of IGF1R.

OBJECTIVE: To compare the effectiveness between paratricipital approach and chevron olecranon V osteotomy approach for the treatment of type C3 (AO/OTA) distal humeral fractures and investigate the details of operation. METHODS: Between April 2010 and September 2016, 36 type C3 (AO/OTA) distal humeral fractures were treated with open reduction and bicolumnar orthogonal locking plating fixation by paratricipital approach and chevron olecranon V osteotomy approach respectively. The patients were divided into 2 groups by approach, there were 17 cases in paratricipital group (group A) and the bicolumns and distal humeral joint surface were exposed by traction of triceps and olecranon, and the distal humeral joint surface of the 19 cases in chevron olecranon V osteotomy group (group B) were exposed by osteotomy of the olecranon and reversing of triceps. There was no significant difference in gender, age, dominant side, interval between injury and surgery, causes of injury between 2 groups (P>0.05). Patients were followed up, the postoperative range of motion of elbow joint, strength, pain, and stability in 2 groups were documented and compared; the elbow joint function was evaluated according to Mayo elbow performance score (MEPS). RESULTS: The operation time of group A [(115.0±10.4) minutes] was less than that of group B [(121.0±12.3) minutes], but there was no significant difference (t=–1.580, P=0.123). All patients in 2 groups got over 1 year follow-up and there was no significant difference of the follow-up time between 2 groups (t=–0.843, P=0.405). There was 1 case of heterotopic ossification in each group; 1 case of incision infection in group A and 1 case of incision superficial infection in group B, and were cured after 2 weeks of intravenous antibiotics administration. There was no other operative complications in the 2 groups. At 3 months after operation, all the distal humerus healed. At last follow-up, the elbow flexion extension range of groups A and B were (102.0±12.6)° and (99.5±10.1)° respectively, showing no significant difference (t=–0.681, P=0.501). The MEPS scores of groups A and B were 82.9±7.3 and 81.3±7.2 respectively, showing no significant difference (t=0.670, P=0.507); and the evaluation grade also showed no significant difference between 2 groups (Z=–0.442, P=0.659). CONCLUSION: By paratricipital approach and proper traction of the olecranon, the distal humeral articular surface can be exposed in the operation of type C3 distal humeral fractures, followed with same stable fixation after reduction, the effectiveness is equal to by chevron olecranon V osteotomy approach.

To explore the effectiveness of distal humeral dual-planar osteotomy followed with distal humeral lateral column anotomical locking plate fixation in the treatment of adult cubitus varus deformity combined with flexion restriction.The clinical data of 6 adult patients with cubitus varus deformity and flexion restriction treated with dual-planar osteotomy and internal fixation between April 2012 and September 2014 were reviewed. There were 3 males and 3 females with an average age of 22.2 years (range, 18-35 years). All the patients had history of elbow injury in childhood, the age being injured was 6.5 years on average (range, 2-13 years). There was no nerve injury, elbow strength weak, or unstable complications before admission. The preoperative elbow flexion was (107.50±5.24)°, elbow extension was (-12.17±3.48)°; the carring angle was (-19.50±4.46)°, the contralateral elbow carrying angle was (11.50±2.67)°; the length of humerus was (0.42±0.38) cm shorter than the unaffected humerus. The postoperative carrying angles, elbow flexion and extension, and humerus length were recorded. The modified Laupattarakasem criteria in which the comparison of bilateral elbow range of motion excluded was used to evaluate the results.Primary healing of incision was got in all patients and there was no early postoperative complications. All the patients were followed up 19-27 months (mean, 20.8 months). During the follow-up, there was no complication such as loosening and breakage of the internal fixators and all fractures were healed within 3 months after operation. At last follow-up, the elbow flexion was (124.17±5.85)°, the elbow extension was (0.83±2.04)°, the carrying angle was (12.00±4.19)°, and the humerus shortening was (1.88±0.45) cm, all showing significant difference when compared with preoperative ones (Normal carrying angle can be restored and elbow flexion can be increased by coronal closing wedge and sagittal trapezoid dual-planar osteotomy, single lateral anatomical locking plate fixation is available for early mobilization.探讨肱骨远端冠状面和矢状面双平面截骨矫形并外侧解剖锁定板固定治疗成人肘内翻畸形的疗效。.回顾分析 2012 年 4 月—2014 年 9 月采用肱骨远端冠状面和矢状面双平面截骨并外侧解剖锁定板固定治疗的 6 例成人肘内翻并肘关节屈曲受限患者临床资料。其中男 3 例，女 3 例；年龄 18～35 岁，平均 22.2 岁。均有明确儿童期肘关节骨折病史，受伤年龄为 2～13 岁，平均 6.5 岁。入院检查 6 例患者均无神经损伤、肘关节屈伸力量异常和不稳定等并发症。术前肘关节屈曲活动度（107.50±5.24）°，伸直活动度（–12.17±3.48）°；患侧提携角为（–19.50±4.46）°，健侧提携角为（11.50±2.67）°；患侧肱骨相对健侧短缩（0.42±0.38）cm。术后随访测量肘关节屈伸活动度、提携角、双侧肱骨短缩，采用去除双肘屈伸活动度对比的改良 Laupattarakasem 标准评定疗效。.术后患者切口均Ⅰ期愈合，无术后早期并发症发生。6 例患者均获随访，随访时间 19～27 个月，平均 20.8 个月。随访期间无内固定物松动断裂等并发症，骨折端均于术后 3 个月内获得骨性愈合。末次随访时肘关节屈曲活动度为（124.17±5.85）°，伸直活动度为（0.83±2.04）°，提携角为（12.00±4.19）°，肱骨短缩为（1.88±0.45）cm，均较术前显著改善（采用双平面截骨矫形可有效矫正肘内翻畸形并改善屈曲活动度，外侧解剖锁定板固定可满足术后早期活动的稳定要求。.

In order to evaluate the genetic diversity and genetic structure of wild Dipsacus asperoides, we surveyed genetic polymorphisms in 288 individuals from 12 populations using ISSR. A total of 240 bands were amplified, among which 190 were polymorphic loci. At the species level, genetic diversity was found to be abundant: PPB = 79.17%, NE = 1.2152, H = 0.1361, and Hsp = 0.2213. At the population level, genetic diversity was lower: PPB = 30.76 %, NE = 1.0786, H = 0.0897, and Hpop = 0.1375. The calculated Nei genetic differentiation coefficient was 0.3406, which is consistent with the calculated Shannon population genetic differentiation coefficient of 0.3787. This is commonly taken to indicate that most of the genetic variation existed within the populations. Gene flow was calculated as Nm = 0.9679, suggesting that gene exchange only occurred at a low level. Based on the Nei genetic distance, the 12 populations were divided into 4 categories. Our results suggest that D. asperoides has abundant genetic diversity and provides a foundation for the protection and improvement of germplasm resources.

Surface-enhanced Raman scattering (SERS) has shown great promise for trace detection due to its high sensitivity. The lack of efficient fabrication methods for large-scale SERS substrates with high sensitivity, high reproducibility, and stability has greatly limited the development of practical SERS sensing devices. In this work, we report sub-diffraction, high throughput, and low-cost fabrication of SERS substrates with plasmonic cavity lens (PCL) lithography. The PCL is a photoresist layer sandwiched with two Ag layers, which could greatly improve the lithographic resolution and fidelity. Ag nanohole arrays (AgNHs) over a 5 × 5 mm2 area were fabricated onto the bottom Ag reflective layer, which worked as SERS substrates. The SERS substrates exhibited enhancement factors (EFs) of 107 that are capable of monolayer detection. The reproducibility is less than 9%, which is much better than that of substrates synthesized with traditional chemical methods. The graphene (GE) layer was transferred onto AgNHs to increase the SERS stability, as demonstrated with only a 25.8% decrease of SERS intensity for 90 day exposure to air and a 78.3% decrease for the control case without GE. This work has demonstrated that PCL lithography technique is a promising method for fabrication of SERS substrates with large-area, high sensitivity, high reproducibility, and low-cost.

Two-dimensional metasurface has attracted growing interest in recent years, owing to its ability in manipulating the phase, amplitude and polarization state of electromagnetic wave within a single interface. However, most existing metasurfaces rely on the collective responses of a set of discrete meta-atoms to perform various functionalities. In this paper, we presented a quasi-continuous metasurface for high-efficiency and broadband beam steering in the microwave regime. It is demonstrated both in simulation and experiment that the incident beam deviates from the normal direction after transmitting through the ultrathin metasurface. The efficiency of the proposed metasurface approximates to the theoretical limit of the single-layer metasurface in a broad frequency range, owing to the elimination of the circuit resonance in traditional discrete structures. The proposed scheme promises potential applications in broadband electromagnetic modulation and communication systems, etc.

The technique of equal-channel angular pressing (ECAP) was used to refine the microstructure of an AISI 301 austenitic stainless steel (SS). An ultrafine-grained (UFG) microstructure consisting mainly of austenite and a few martensite was achieved in 301 steel after ECAP processing for four passes at 523 K (250 °C). By submitting the as-ECAP rods to annealing treatment in the temperature range from 853 K to 893 K (580 °C to 620 °C) for 60 minutes, fully austenitic microstructures with grain sizes of 210 to 310 nm were obtained. The uniaxial tensile tests indicated that UFG 301 austenitic SS had an excellent combination of high yield strength (>1.0 GPa) and high elongation-to-fracture (>30 pct). The tensile stress–strain curves exhibited distinct yielding peak followed by obvious Luders deformation. Measurements showed that Luders elongation increased with an increase in strength as well as a decrease in grain size. The microstructural changes in ultrafine austenite grains during tensile deformation were tracked by X-ray diffraction and transmission electron microscope. It was found that the strain-induced phase transformation from austenite to martensite took place soon after plastic deformation. The transformation rate with strain and the maximum strain-induced martensite were promoted significantly by ultrafine austenite grains. The enhanced martensitic transformation provided extra strain-hardening ability to sustain the propagation of Luders bands and large uniform plastic deformation. During tensile deformation, the Luders bands and martensitic transformation interacted with each other and made great contribution to the excellent mechanical properties in UFG austenitic SS.

Tunable multiband polarization conversion and manipulation are achieved by introducing vanadium dioxide (VO2) into a planar spiral asymmetric chiral metamaterial. Numerical simulations demonstrate that when VO2 is in the insulating state, circularly polarized electromagnetic waves are emitted at two distinct resonant frequencies. When VO2 is in the metallic state, the number of resonant frequencies changes from two to four. In addition, the initial left-handed and right-handed circularly polarized transmitted waves correspondingly transform into right and left ones. Moreover, the surface current distributions are studied in order to investigate the transformation behaviors of both the insulating and metallic states.

A coarse-grained Cu-16 wt.% Ag alloy was processed by equal channel angular pressing (ECAP) for one pass to reveal the shear deformation behaviors by scanning electron microscope and electron backscattering diffraction. The evolution of shear bands was found to be affected by both the parallel and vertical shearing to the intersection plane (IP) of the ECAP die, indicating that, besides the shearing along IP, the shearing vertical to it also plays an important role during the plastic deformation. (C) 2009 Published by Elsevier Ltd. on behalf of Acta Materialia Inc.

The microstructures and tensile properties of a commercial heat-resistant martensitic steel processed by equal channel angular pressing (ECAP) for one pass and subsequent ageing treatment were investigated. Both optical and TEM examinations showed that many martensite laths had been broken into dislocation cells and subgrains after ECAP deformation. At the same time, the fragmentation of rod-shaped precipitates was also observed and the distribution of precipitation was more uniform than that in the as-received sample. After ageing in the temperature range of 640–720 °C for 2 h, dislocation recovery took place resulting in the decrease of dislocation density and formation of many ultrafine grains with sizes of several hundred of nanometers, and spherical particles that were uniformly dispersed in the matrix of fine subgrains/grains. By ECAP deformation and subsequent ageing treatment, a simultaneous increase in both strength and toughness was achieved, compared with those of as-received state. The enhancement of tensile properties was attributed to microstructural refinement and uniform distribution of precipitates.

The microstructures and tensile deformation behavior of Cu-16 wt.% Ag binary alloy with coarse grains were investigated by electron backscattered diffraction (EBSD) and scanning electron microscope (SEM). No precipitate was found in both eutectic Cu and Ag phases, whereas abundant precipitates were observed in proeutectic Cu matrix. Slip bands appear in the dendrites, though they are abundant in precipitates, and this can be attributed to the cube-on-cube orientation relationship and the coplanar slip systems between them. Slip bands can penetrate continuously through the eutectic region and the dendrites. The EBSD results revealed that they always had the same orientation. The tensile stress-strain curves displayed certain work-hardening behavior and high elongation. The highly continuous slip deformation mode and the good strain compatibility between matrix and the eutectic region will be beneficial to the high elongation of the Cu-Ag alloy. (C) 2009 Elsevier B.V. All rights reserved.

An investigation was conducted on the tensile and compressive properties of commercially pure Al processed by equal-channel angular pressing (ECAP) with two different dies. The specimens along two different directions were cut from the ECAPed billets to study the effect of orientation on the compressive yield strength and the surface deformation morphologies along normal direction (ND) and extrusion direction (ED). It was found that the yield strength of the specimens along ED under tension was lower than that along ED under compression, but higher than that along ND under compression. The surface observations showed that there were some differences in the deformation morphologies under compression along two different directions. Based on the mechanical tests and observations of surface morphologies of ECAPed pure Al, the relationship between shear deformation behavior and tension/compression asymmetry was discussed.

The deformation mechanism of equal-channel angular pressing (ECAP) was investigated by in-situ physical modeling experiment, in which the billet consisting of two kinds of color grains with designed patterns was pressed through an ECAP die made of a transparent plexiglass. It was found that the evolution of the flow patterns was governed by the geometric character of ECAP die, and a deformation zone with a sector shape was formed in billet during the experiments. Based on the observations in the in-situ physical modeling experiment, a simple flow line field and the corresponding geometrical aspect of shear deformation were proposed.

It is commonly accepted that twinning can induce an increase of strain-hardening rate during the tensile process of face-centered cubic (FCC) metals and alloys with low stacking fault energy (SFE). In this study, we explored the grain size effect on the strain-hardening behavior of a Cu-15 at.%Al alloy with low SFE. Instead of twinning, we detected a significant contribution of stacking faults (SFs) irrespective of the grain size even in the initial stage of tensile process. In contrast, twinning was more sensitive to the grain size, and the onset of deformation twins might be postponed to a higher strain with increasing the grain size. In the Cu-15 at.%Al alloy with a mean grain size of 47 μm, there was a stage where the strain-hardening rate increases with strain, and this was mainly induced by the SFs instead of twinning. Thus in parallel with the TWIP effect, we proposed that SFs also contribute significantly to the plasticity of FCC alloys with low SFE., 構造材料の変形挙動に新たな視点 -強さとねばさを兼備した材料開発へ-. 京都大学プレスリリース. 2015-11-20.

Objective: A randomized trial was performed to evaluate the contribution of gan lu fu zheng soup with chemotherapy plus radiotherapy (CT/RT) in the patients with histologically proven nasopharyngeal carcinoma with local metastasis to lymph nodes. Methods: Sixty-eight patients with nasopharyngeal carcinoma were treated either with gan lu fu zheng soup alongside with chemotherapy and radiotherapy (TCM/CT/RT group) or with chemotherapy and radiotherapy (CT/RT group) alone. All patients in the two groups were treated with a uniform definitive-intent radiation therapy and chemotherapy, while those patients in the TCM/CT/RT group were treated with extra gan lu fu zheng soup. Results: From 1999 to 2002, 68 patients (38 in TCM/CT/RT, 30 in CT/RT group) were enrolled and eligible. The rates of complete resolution of nasopharyngeal tumors in the treatment group and the control group were respectively, 94.7% and 90%; the rates of complete resolution of cervical lymph node metastases were respectively, 92.1% and 83%; the resolution rates of nasopharyngeal foci examined by CT were respectively, 73.6% and 63.3%; and the total survival rates of one year were respectively, 100.0% and 96.7% (P > 0.05). Changes in clinical symptoms: the total amelioration rates of the two groups were respectively, 97.4% and 76.7%; changes in life quality: the amelioration rates of the two groups were respectively, 89.5% and 66.7%; toxic and side reactions: in comparison with the control group, the treatment group were also distinctly relieved from leukopenia, nausea and vomiting, toxic and side reaction of oral mucosa. Through statistic analysis, the differences are of significances (P < 0.05). Conclusions: Treating nasopharyngeal carcinoma with gan lu fu zheng soup in combination with radiotherapy and chemotherapy is helpful to increase the rates of tumor resolution and complete resolution, to protect immunocompetence of organism, to promote the amelioration of clinical symptoms, to alleviate the toxic and side reaction of radiotherapy and chemotherapy, to increase life quality and prolong survival time, which provides an effective auxiliary means for the treatment of nasopharyngeal carcinoma.

Ascribing to the properties of two dimensional parallel focusing and imaging, low propagation loss, integration and miniaturization, microlens array has been widely used in imaging, optical communication, organic light emitting devices, adaptive optics, photolithography, biomedical and other applications. However, the existing traditional microlens array suffers from difficulty in fabrication, large-thickness, curved surface, non-uniformity of light spots, or requirement of additional discrete components to control the microlens. Herein, a planar microlens array is experimentally demonstrated based on the geometric metasurface. The single microlens is composed of space-variant subwavelength metallic gratings with high polarization conversion efficiency and thus exhibits gradient phase distribution. The focused spot diameter of 22.5 μm with radius of 350 μm, focal length of 1 cm and the light spots intensity uniformity of 0.9885 (standard deviation 0.0115) at the focal plane are obtained. Moreover, the broadband property of microlens array is also confirmed. The novel design strategy for microlens array would facilitate the miniaturization of optical devices and be easily integrated in the optical interconnected devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA.

The direct alpha-alkylation of ketones with alcohols has emerged as a new green protocol to construct C-C bonds with H2O as the sole byproduct. In this work, a very simple and convenient Pd/C catalytic system for the direct alpha-alkylation of ketones with primary alcohols in pure water is developed. Based on this catalytic system, aqueous mixtures of dilute acetone, 1-butanol, and ethanol (mimicking ABE fermentation products) can be directly transformed into C-5-C-11 or longer-chain ketones and alcohols, which are precursors to fuels.

The direct alpha-alkylation of ketones with alcohols has emerged as a new green protocol to construct C-C bonds with H2O as the sole byproduct. In this work, a very simple and convenient Pd/C catalytic system for the direct alpha-alkylation of ketones with primary alcohols in pure water is developed. Based on this catalytic system, aqueous mixtures of dilute acetone, 1-butanol, and ethanol (mimicking ABE fermentation products) can be directly transformed into C-5-C-11 or longer-chain ketones and alcohols, which are precursors to fuels.

Wild Dipsacus chinensis plants in China have become endangered owing to over-harvesting and habitat fragmentation. We examined the genetic diversity and genetic structure of 90 individuals from three populations using inter-simple sequence repeat markers and found that 106 of 173 bands amplified by 22 informative and reliable primers were polymorphic. These findings correspond to a medium level of genetic diversity. At the species level, the estimates of parameters of genetic diversity were as follows: polymorphic loci (61.27%); effective number of alleles (1.3873); Nei's genetic diversity (0.2202); Shannon's information index (0.3235). At the population level, the estimates were polymorphic loci (9.53%); effective number of alleles (1.0419); Nei's genetic diversity (0.0258); Shannon's information index (0.0402). Nei's coefficient of genetic differentiation was 0.8829, which is consistent with Shannon's coefficient of genetic differentiation (0.8757). Most of the genetic variation existed among populations, and some differentiation may have resulted from habitat fragmentation and barriers to gene flow (gene flow = 0.0663). Combining our results with those of on-site field investigation, we conclude that the present genetic diversity and genetic structure of natural populations of D. chinensis have been strongly affected by harvesting and habitat fragmentation. We also propose strategies for the conservation of this plant.