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By attaching a few kinds of two aryl-side groups into pyrene core at 5,9-positions, five pyrene-based color-tunable blue emitters have been developed for highly efficient nondoped and doped blue OLEDs.

In this paper, we manufactured a novel sandwich panel that comprised of the foam core and the hybrid facesheets by vacuum-assisted resin infusion process. In the hybrid facesheets, the reinforcing phases are made of woven glass fabric cloth in company with wire nets, while the matrix is epoxy resin. Four categories of specimens with different wire nets contents are designed. To investigate the impact resistance ability of the designed sandwich panel, low-velocity impact tests are performed with respect to the contact load, absorbed energy, and failure mode. Compression-after-impact test is conducted to determine the residual mechanical properties of the postimpact sandwich panels. Digital image correlation technology is adopted to measure the strain distribution in the panels in compression-after-impact test. Results show that wire nets in the facesheet of the sandwich panel could enhance the energy absorb ability as well as the compression-after-impact strength significantly. Fiber/wire nets breaking, delamination, and foam core cracking are the main damage modes formed in the impact event, while the incident energy is mainly absorbed by wire nets breaking. In compression-after-impact test, bucking and delamination are the main damage modes, and the compressive stability is enhanced by the wire nets.

A series of twistacene-functionalized donor (D)-π-acceptor (A) derivatives (2-5) have been designed and synthesized, in which twistacene can be regarded as a promising platform for electron-rich systems for fluorescence emitters. The connecting modes and various acceptors are also examined to investigate the effect of structural changes on the photophysical, electrochemical, and thermal properties. The strong electron-withdrawing capability of the arylboron-modified benzonitrile unit can effectively separate the HOMO and LUMO energy levels of 4/5, which is beneficial for the formation of thermally activated delayed fluorescence (TADF) molecules. Cyan and orange organic light-emitting diodes based on 4 and 5 exhibit promising electroluminescence with a maximum brightness of 7643 cd m-2 for device-4 and 14871 cd m-2 for device-5.

The instability of large acenes and analogues usually limits their wide potentials in organic devices. Thus, effectively constructing large acenes or heteroacenes and examining their optoelectronic properties are of great interest. We herein describe the synthesis, optoelectronic behaviors and electroluminescent property of dimesitylboryl-decorated azaarene 5 and its homologue 7. The former emits strong green fluorescence in non-polar solvents but yellow light in polar solvents. The latter emits a blue light in various organic solvents. Moreover, their electrochemical behavior, photostability and electroluminescent property were further studied in a comparative manner, and the experimental findings suggest that the desired heteroarenes are appealing materials for fabricating electroluminescent devices.

Three novel furanacenes (5/D5c) have been synthesized and characterized. Single-crystal analyses suggested that the as-prepared molecules 5a/5b formed twisted configurations. The absorption and emission spectra of these compounds (5/D5c) and their precursors, alkynyl-modified acenes (3), were measured to uncover the substituent effect on their optoelectronic properties. Twistfuranacenes 5a/5b and substituted twistacenes 3 emit strong blue light, and the triphenylamine-decorated π-system D5c exhibited obviously red-shifted fluorescence. Nonlinear spectroscopic investigation illustrated that the cyclized furanacenes 5/D5c presented larger two-photon absorption cross section than twistacenes 3, being attributed to the introduction of more delocalized electrons from electron-rich furan units. Apparently, these observations might be beneficial for the design of novel twistacenes/heteroacenes and the development of organic photonic materials.

Cardiovascular disease (CVD) is the most common type of disease and has a high fatality rate in humans. Early diagnosis is critical for the prognosis of CVD. Before using myocardial tissue strain, strain rate, and other indicators to evaluate and analyze cardiac function, accurate segmentation of the left ventricle (LV) endocardium is vital for ensuring the accuracy of subsequent diagnosis. For accurate segmentation of the LV endocardium, this paper proposes the extraction of the LV region features based on the YOLOv3 model to locate the positions of the apex and bottom of the LV, as well as that of the LV region; thereafter, the subimages of the LV can be obtained, and based on the Markov random field (MRF) model, preliminary identification and binarization of the myocardium of the LV subimages can be realized. Finally, under the constraints of the three aforementioned positions of the LV, precise segmentation and extraction of the LV endocardium can be achieved using nonlinear least-squares curve fitting and edge approximation. The experiments show that the proposed segmentation evaluation indices of the method, including computation speed (fps), Dice, mean absolute distance (MAD), and Hausdorff distance (HD), can reach 2.1–2.25 fps, 93.57 ± 1.97 % , 2.57 ± 0.89 mm, and 6.68 ± 1.78 mm, respectively. This indicates that the suggested method has better segmentation accuracy and robustness than existing techniques.

Numerous long noncoding RNAs (lncRNAs) are reported to be dysregulated in glioma. However, how lncRNA participates in the process of glioma development and progression still remains elusive. Here, we identified a novel lncRNA LOC728196 highly expressed in glioma tissues. LOC728196 high expression predicts low survival rate in patients. Our data proved that LOC728196 knockdown repressed cellular growth, migration and invasion in vitro. Silencing LOC728196 led to impaired growth of glioma in vivo. Mechanistic studies further demonstrated that LOC728196 acts as the sponge for miR-513c to upregulate TCF7 expression. We observed a reciprocal inhibition between LOC728196 and miR-513c. Rescue assay showed that either inhibition of miR-513c or TCF7 overexpression restored the abilities of proliferation, migration and invasion in LOC728196-silenced glioma cells. Taken together, our study provides a comprehensive investigation on the role of LOC728196 in glioma progression and contributes to understanding the vital role of competing endogenous RNA (ceRNA).

In this work, a novel malononitrile-modified acene 2-(2,7-di-tert-butyl-9,17-diphenyl-15H-dibenzo[hi,mn]indeno[1,2-b]tetracen-15-ylidene) malononitrile (DITAM) has been synthesized and characterized. Its single crystal X-ray analysis shows that DITAM features an antiparallel configuration and has a cis-form in the packing model, which is different from its analogue 2,7-di-tert-butyl-9,17-diphenyl-15H-dibenzo[hi,mn]indeno[1,2-b]tetracene (DITA). In comparison with UV–vis absorption and fluorescence spectra in different solvents of compounds DITAM, DITAO, and DITA, molecule DITAM displays the strongest salvation, inferring that ICT occurs in the excited state. Electrochemical results combined with the theoretical calculation illustrate that the malononitrile unit can effectively lower the LUMO energy level. The third-order nonlinear optical behaviors of the as-prepared compounds were investigated in a comparative manner, where DITAM exhibited the best optical nonlinear performance.

Doping heteroatoms into the skeletons of parent acenes can provide more opportunities to construct novel thermally and photostable organic π-conjugated semiconductors. Herein, a family of diazole-decorated acenes (APyS and APySe) and azaacenes (PyP, PyTh, PyPy, PyPh, and PyAP) have been successfully synthesized through the classical reactions. Single-crystal X-ray analyses showed that these as-formed diazole-modified derivatives adopted a twisted topology configuration, whereas the azaacenes display reclining-chair architectures, besides a twisted structure. All these compounds displayed yellow or red light in solution. Moreover, their electrochemical behaviors were also examined. We also found that the azaacenes exhibited a positive spectroscopic response to acid.

Two novel diazadioxaacene derivatives (ADOP and ADOQ) have been successfully synthesized and characterized. Their single crystal analyses disclose that molecule ADOP forms a twisted topology configuration, whereas ADOQ adopts reclining-chair architecture. Both of them emit strong blue fluorescence in organic solvents. Moreover, they can self-assemble to form regular nanobelts and nanowires, respectively, via a simple surfactant-assisted method.

Enormous enormous subgaleal hematoma with epidural extension, accompanying occipital bone's absorption is an uncommon complication of hemophilia A. A 30 years old man presenting scalp lump was found enormous enormous subgaleal hematoma with epidural extension, accompanying occipital bone's destruction by computed tomography (CT) scan, and laboratory examination indicated that the concentration of his factor VII was 2% of normal level. Further inquiring his medical history found that this patient has been suffering from hemophilia A diagnosed when he was 6 years old. He recovered well after receiving the therapertic methods of factor VII replacement and surgical decompression. This case tells us that patient suffering from enormous enormous subgaleal hematoma with epidural extension, accompanying occipital bone's destruction and hemophilia A could recover well as long as he is well treated. Keywords: Neurosurgery, Factor VII, Enormous subgaleal hematoma with epidural extension, occipital bone's destruction, Hemophilia A

As a result of the high specific strength/stiffness to mass ratio, filament wound composite pressure vessels are extensively used to contain gas or fluid under pressure. The ability to in-situ monitor the composite pressure vessels for possible damage is important for high-pressure medium storage industries. This paper describes an in-situ monitoring method to permanently monitor composite pressure vessels for their structural integrity. The sensor is made of a multi-walled carbon nanotube (MWCNT) that can be embedded in the composite skin of the pressure vessels. The sensing ability of the sensor is firstly evaluated in various mechanical tests, and in-situ monitoring experiments of a full-scale composite pressure vessel during hydraulic fatigue cycling and pressurization are performed. The monitoring results of the MWCNT sensor are compared with the strains measured by the strain gauges. The results show that the measured signal by the developed sensor matches the mechanical behavior of the composite laminates under various load conditions. In the hydraulic fatigue test, the relationship between the resistance and the strain is built, and could be used to quantitative monitor the filament wound pressure vessel. The bursting of the pressure vessel can be detected by the sharp increase of the MWCNT sensor resistance. Embedding the MWCNT sensor into the composite pressure vessel is successfully demonstrated as a promising method for structural health monitoring.

A genome-wide association study has shown a number of chicken (Gallus gallus) single nucleotide polymorphism (SNP) markers to be significantly associated with abdominal fat content in Northeast Agricultural University (NEAU) broiler lines selected divergently for abdominal fat content (NEAUHLF). The six significant SNPs are located in the kinase insert domain receptor (KDR), tumor suppressor candidate 3 (TUSC3), phosphoribosyl pyrophosphate amidotransferase (PPAT), exocyst complex component 1 (EXOC1), v-myb myeloblastosis viral oncogene homolog (avian)-like 2 (MYBL2) and KIAA1211 (undefined) genes. In this study, the expression levels of these genes were investigated in both abdominal fat and liver tissues using 32 14th generation chickens from the NEAUHLF. The levels of expression of KDR in abdominal fat and KDR and TUSC3 in liver differed significantly between the two lines. The expression level of KDR in the abdominal fat was significantly correlated with the abdominal fat weight (AFW) and abdominal fat percentage (AFP). The expression levels of KDR, TUSC3 and PPAT in liver were significantly correlated with AFW and AFP, indicating that the six genes, especially KDR and TUSC3, could be associated with fat traits in domestic chickens. This study could provide insight into the mechanisms underlying the formation of abdominal fat in chickens.

Emerging evidences show RNA back-splicing produces a new type of noncoding RNA, namely circular RNA (circRNA). Many reports demonstrate that circRNA circHIPK3 exerts oncogenic or anti-tumor roles in different cancers, such as ovarian cancer, bladder cancer, osteosarcoma, colorectal cancer and liver cancer. However, no study about circHIPK3 function in glioma exists until today. In this study, we showed that circHIPK3 was upregulated in glioma tissues. Elevated level of circHIPK3 was linked to poor prognosis. Functional investigation indicated that circHIPK3 promotes glioma cell proliferation and invasion, and tumor propagation in vivo. Furthermore, miR-654 was identified as a target of circHIPK3 while IGF2BP3 was targeted by miR-654. CircHIPK3 could promote IGF2BP3 expression via interacting with miR-654 in glioma cells. Finally, CCK8 and transwell assays illustrated that IGF2BP3 overexpression could reverse the effects of IGF2BP3 depletion. Altogether, our findings demonstrated that circHIPK3 contributes to glioma progression through targeting miR-654 from IGF2BP3 and implies circHIPK3 might be a potential target for glioma therapy.

Acenes, usually defined as segments of “graphene”, consist of linearly annulated benzene rings, and have attracted considerable interest in both theoretical research and practical applications. However, these compounds generally have undesirable features such as poor solubility, easy oxidation and photodimerization. Thus, scientists have to invest much effort to address these problems and experimentally achieve the desired electronic properties to meet various demands. Herein, we summarize recent progress in the synthesis of pyrene‐functionalized acenes and heteroacenes through the use of pyrene diketone and pyrene tetraketone building blocks. Moreover, the physical properties and applications of these semiconductors in organic semiconductor devices are also described. MOE (Min. of Education, S’pore)

A series of twistacenes with different substituents have been synthesized, characterized, and their nonlinear optical properties in the solid state have been explored. It is demonstrated that 2,7-di-tert-butyl-N,9,20-triphenyltetrabenzo[a,c,jk,op]pentacen-11-amine crystals having a centrosymmetric C2/c space group exhibit third-order and strong second-order nonlinear optical responses with well-defined polarization dependencies.

Hormone-sensitive lipase-knockout (HSL−/−) mice exhibit azoospermia for unclear reasons. To explore the basis of sterility, we performed the following three experiments. First, HSL protein distribution in the testis was determined. Next, transcriptome analyses were performed on the testes of three experimental groups. Finally, the fatty acid and cholesterol levels in the testes with three different genotypes studied were determined. We found that the HSL protein was present from spermatocyte cells to mature sperm acrosomes in wild-type (HSL+/+) testes. Spermiogenesis ceased at the elongation phase of HSL−/− testes. Transcriptome analysis indicated that genes involved in lipid metabolism, cell membrane, reproduction and inflammation-related processes were disordered in HSL−/− testes. The cholesterol content was significantly higher in HSL−/− than that in HSL+/+ testis. Therefore, gene expression and cholesterol ester content differed in HSL−/− testes compared to other testes, which may explain the sterility of male HSL−/− mice.

Aimed at portable application, a new integrated process chip for thin film bulk acoustic resonator (FBAR) mass sensor is proposed and verified with 0.18 um CMOS processing in this paper. The longitudinal mode FBAR with back-etched structure is fabricated, which has resonant frequency 1.878 GHz and factor 1200. The FBAR oscillator, based on the current-reuse structure, is designed with Modified Butterworth Van Dyke (MBVD) model. The result shows that the FBAR oscillator operates at 1.878 GHz with a phase noise of −107 dBc/Hz and −135 dBc/Hz at 10 KHz and 100 KHz frequency offset, respectively. The whole process chip size with pads is 1300 μm × 950 μm. The FBAR and process chip are bonded together to sense tiny mass. The measurement results show that this chip precision is 1 KHz with the FBAR frequency gap from 25 kHz to 25 MHz.

Cylindrical vector beams are described by the representation formalism of finite electromagnetic beams in free space. This is achieved by factorizing the field vector into a mapping matrix and a Jones-like vector. The vectorial property of a finite beam can be described by a degree of freedom of the mapping matrix that can be determined by the azimuthal angle of a fixed unit vector with respect to the wave vector. In addition, it is a simple and flexible experimental device for converting linearly polarized light beams into cylindrical vector beams. The radially or azimuthally polarized beam is easily converted into either one of these by varying the applied voltage.

Organic/inorganic hybrid multilayer films with noncentrosymmetrically orientated azobenzene chromophores were fabricated by the sequential deposition of ZrO2 layers by a surface sol-gel process and subsequent layer-by-layer (LbL) adsorption of the nonlinear optical (NLO)-active azobenzene-containing polyanion PAC-azoBNS and poly(diallyldimethylammonium chloride) (PDDA). Noncentrosymmetric orientation of the NLO-active azobenzene chromophores was achieved because of the strong repulsion between the negatively charged ZrO(2) and the sulfonate groups of the azobenzene chromophore in PAC-azoBNS. Regular deposition of ZrO(2)/PAC-azoBNS/PDDA multilayer films was verified by UV-vis absorption spectroscopy and quartz crystal microbalance measurements. Both UV-vis absorption spectroscopy and transmission second harmonic generation (SHG) measurements confirmed the noncentrosymmetric orientation of the azobenzene chromophores in the as-prepared ZrO2/PAC-azoBNS/PDDA multilayer films. The square root of the SHG signal (I(2omega)(1/2)) increases with the increase of the azobenzene graft ratio in PAC-azoBNS as the number of deposition cycles of the ZrO(2)/PAC-azoBNS/PDDA films remains the same, while the second-order susceptibility chi(zzz)(2) of the film decreases with the increase of the azobenzene graft ratio. Furthermore, the present method was successfully extended to realize the noncentrosymmetric orientation of azobenzene chromophores in multilayer films when small organic azobenzene compounds with carboxylic acid and/or hydroxyl groups at one end and sulfonate groups at the other end were used. The present method was characterized by its simplicity and flexibility in film preparation, and it is anticipated to be a facile way to fabricate second-order nonlinear optical film materials.

Previous results from genome wide association studies (GWASs) in chickens divergently selected for abdominal fat content of Northeast Agricultural University (NEAUHLF) showed that many single nucleotide polymorphism (SNP) variants were associated with abdominal fat content. Of them, six top significant SNPs at the genome level were located within SRD5A3, SGCZ, DLC1, GBE1, GALNT9 and DNAJB6 genes. Here, expression levels of these six candidate genes were investigated in abdominal fat and liver tissue between fat and lean broilers from the 14th generation population of NEAUHLF. The results showed that expression levels of SRD5A3, SGCZ and DNAJB6 in the abdominal fat and SRD5A3, DLC1, GALNT9, DNAJB6 and GBE1 in the liver tissue differed significantly between the fat and lean birds, and were correlated with abdominal fat traits. The findings will provide important references for further function investigation of the six candidate genes involved in abdominal fat deposition in chickens.

Femtosecond-laser-induced shock waves in aluminum film deposited on alpha-quartz were generated at a repetition of up to ten shocks per second. Using ultrafast time-resolved microscopy of shock waves in different thickness of aluminum films, the shock velocity propagated in aluminum was measured to be 9.0±0.7 km/s. With shock wave equations of state, shock pressures in aluminum and α-quartz were calculated to be 66(±15) GPa and 56(±15) GPa respectively, and final temperatures in aluminum and alpha-quartz were calculated to be 281 °C and 104 °C respectively.

Planar nanosecond shock waves were generated with ultrafast Gaussian laser pulses by using saturable dye-doped polymer film as shock layer. Ultrafast spatially resolved Coherent Anti-Stokes Raman (CARS) spectra of shock compression of a polycrystalline anthracene optical gauge were measured, and temporal profile and velocity of the shock pulse were obtained. Detailed measurements showed the shock pressure, as indicated by the blueshift of an anthracene vibrational transition, and the shock velocity, as indicated by the arrival time of shock wave at the anthracene gauge layer, remains constant within better than 5% over the central region probed by CARS.

Ultrathin films with noncentrosymmetrically orientated azobenzene chromophores were constructed using a combination of layer-by-layer adsorption of polyelectrolytes and the surface sol-gel process.

Film bulk acoustic resonators (FBARs) are typically characterised by a network analyser on a probe station to extract the device parameters, which are then used for circuit design. These measured parameters are different from the intrinsic ones owing to the existence of parasitic effects from the pads and testing environment which may lead to failure of the designed circuits. A method is proposed to extract the intrinsic Q-factor and resonant frequencies of the FBARs from the measured S-parameters. Results show that the intrinsic series resonant frequency could be a few megahertz different from the measured one, and the intrinsic Q-factors could be up to 100% larger than the measured ones.