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A wideband folded reflectarray antenna (FRA) based on single-layered polarization rotating metasurface (PRM) is proposed. The FRA is composed of a wideband polarization grid (PG), a wideband PRM and a wideband circular waveguide as the primary source. First, a wideband polarization rotating unit cell consisting of rhombus-shaped metal patch etched on dielectric substrate is designed, which can be used to rotate polarization of the reflective wave 90° relative to that of the incident wave. The element and its mirror image can provide 0°, 90°, 180° and 270° phase shifts with 2-bit phase quantization and relatively higher polarization conversion rates in the Ku band. Due to the introduction of PG and PRM, the distance between the PG surface and the feed phase center can be reduced to about 1/2 of the distance between the imaginary feed and PRM reflectarray. Finally, a wideband FRA consisting of 315 elements with circular aperture is designed, fabricated and measured. The measured results indicate that the proposed antenna achieves 39.5% 3-dB gain bandwidth with 25.5 dBi peak gain at 15 GHz. Its maximum aperture efficiency is about 40%. Low-profile and wideband features of the FRA make it be a candidate in the wireless communication systems.

Bohring-Opitz syndrome (BOS, or BOPS) is a rare congenital genetic disorder with multisystem abnormalities characterized by significant craniofacial dysmorphism, feeding difficulties, severe developmental delay, profound intellectual disability, flexion of elbows with ulnar deviation, and flexion of the wrists and metacarpophalangeal joints. Here, we report two Chinese BOS patients with distinctive phenotypes caused by novel truncating mutations. One was a boy aged 5 years 9 months who had a novel c.1049G>A/p.Trp350* mutation in ASXL1 and displayed relatively mild BOS symptoms with autism features. The other was a 16-month-old boy who carried a novel c.2689delC/p.His897Ilefs*11 mutation and displayed typical BOS symptoms. New cases with novel mutations, along with a detailed clinical and molecular analysis are important for a better diagnosis and understanding of BOS.

Pediatric forearm torus fracture, a frequent reason for emergency department visits, can be immobilized by both rigid cast and nonrigid methods. However, controversy still exists regarding the optimal treatment of the disease. The aim of this study was to compare, in a systematic review, clinical efficacy of rigid cast with nonrigid methods for immobilization of the pediatric forearm torus fractures.Literature search was performed of PubMed and Cochrane Library by 2 independent reviewers to identify randomized controlled trials comparing rigid cast with nonrigid methods for pediatric forearm torus fractures from inception to December 31, 2013, without limitation of publication language. Trial quality was assessed using the modified Jadad scale.Eight randomized controlled trials with a total of 781 participants met all inclusion criteria. The nonrigid methods for immobilization included soft cast, splint, bandage, and slab. Results showed that nonrigid immobilizations had better clinical efficacy than rigid cast regarding functional recovery, treatment cost, and complication rate (relative risk, 3.02; 95% confidence interval, 1.70-5.37; P = 0.0002). Compared with rigid cast, more patients would like to choose the nonrigid methods of immobilization for future use. However, discrepant results sill surrounds the pain levels of the patients.The current study suggests that the nonrigid immobilization methods have more advantages than rigid cast for immobilization of pediatric forearm torus fracture. The former strategies are also safe enough for clinical therapy.

Objective: Whole Exome Sequencing (WES) is an effective diagnostic method for complicated and multi-system involved rare diseases. However, annotation and analysis of the WES result, especially for single case analysis still remain a challenge. Here, we introduce a method called phenotype-driven designing “virtual panel” to simplify the procedure and assess the diagnostic rate of this method.Methods: WES was performed in samples of 30 patients, core phenotypes of probands were then extracted and inputted into an in-house software, “Mingjian” to calculate and generate associated gene list of a virtual panel. Mingjian is a self-updating genetic disease computer supportive diagnostic system that based on the databases of HPO, OMIM, HGMD. The virtual panel that generated by Mingjian system was then used to filter and annotate candidate mutations. Sanger sequencing and co-segregation analysis among the family were then used to confirm the filtered mutants.Result: We first used phenotype-driven designing “virtual panel” to analyze the WES data of a patient whose core phenotypes are ataxia, seizures, esotropia, puberty and gonadal disorders, and global developmental delay. Two mutations, c.430T > C and c.640G > C in PMM2 were identified by this method. This result was also confirmed by Sanger sequencing among the family. The same analysing method was then used in the annotation of WES data of other 29 neurological rare disease patients. The diagnostic rate was 65.52%, which is significantly higher than the diagnostic rate before.Conclusion: Phenotype-driven designing virtual panel could achieve low-cost individualized analysis. This method may decrease the time-cost of annotation, increase the diagnostic efficiency and the diagnostic rate.

Cold welding becomes easier during mechanical alloying in alloy system with ductile and low melting point components. Here, effects of multiple process control agents (PCAs) including volatile PCAs, non-volatile PCAs and no PCA on mechanical alloying of Ni–Ti–Al powders was investigated. It is found that L21 phase Ni–Ti–Al alloys milled with volatile PCAs and no PCA show superior hardness that is much higher than the non-volatile PCAs samples, but all exist serious cold welding. However, the alloy milled with non-volatile PCA exhibits almost identical high hardness as the volatile PCAs and no PCA samples with prolonging milling time. Moreover, cold welding phenomenon is completely avoided by using non-volatile PCAs properly. The particle morphology changes from large flaky at the initial stage to uniform ultrafine particles during milling process. Uniform composition distribution greatly reduces the alloying temperature, which facilitates the formation of L21-Ni2TiAl phase with high hardness.

The composite materials are composed by Z-type hexaferrite and Bi2O3 by solid-state reaction method. Crystalline phase, microstructure and magnetic properties were measured by XRD, SEM, and VNA. The results showed that the sintering temperature and the content of Bi2O3 can effectively affected both uniformity and densification. What's more, Z-type hexaferrite mixed with proper content of Bi2O3 and sintered at a low temperature presented a high Q-factor in a high frequency.

Impact of sample preparation on determination of hydrogen content in TC4 titanium alloys is studied through the experimental test method which was developed according to ASTM E 1447-2009. The simulation of the heating process in sample preparation process verifies the slight warming (60°C ~ 80 °C) will affect the test result of hydrogen content in TC4 titanium alloys. The heating process makes the result be lower than the actual content.

To explore the clinical effect of intertransverse approach microendoscopic discectomy for far lateral lumbar disc herniation.From February 2005 to February 2010, 73 patients with far lateral lumbar disc herniation were treated with intertransverse approach microendoscopic discectomy. Their clinical data were retrospectively analyzed. There were 41 males and 32 females, aged from 19 to 80 years old with an average of 56.5 years; courses of disease ranged from 1 to 25 months with an average of 4.5 months. The main symptom was low back pain and sciatica, especially the sciatica was seriously. Herniation level was in L3,4 of 9 cases, L4,5 of 49 cases, L5S1 of 15 cases. Preoperative, 2 weeks after operation, final follow-up, conditions of pain relief were assessed by visual analogue scale (VAS); total life quality of patients were evaluated by Oswestry Disability Index (ODI) before operation and last follow-up.All operations were performed successfully, operative time was from 40 to 115 min (mean of 50 min); and blood loss was from 50 to 150 ml (mean of 110 ml). Incision infection had 1 case and incomplete nerve root injury had 1 case. All patients were followed up from 3 to 8 years with an average of 4.5 years. Postoperative VAS and ODI had obviously improved (P0.01).The technique of intertransverse approach microendoscopic discectomy is a feasible and effective method for far lateral lumbar disc herniation.