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For the development of safe, non-toxic and environmentally friendly gas generators, a nitrogen-rich compound 5,7-diamine-2-nitro-1,2,4-triazolo[1,5-a]-1,3,5-triazine (ANTT) was synthesized from 3,5-diamine-1,2,4-triazole in two steps. The structure of ANTT was comprehensively characterized and well investigated by X-ray diffraction. The thermal stability, detonation properties and mechanical sensitivities of ANTT were finely studied. ANTT, enjoyed with a high content of nitrogen (57.13 %), as well as a high decomposition temperature of 358.5 °C, high self-accelerating decomposition temperature of 340.3 °C, high critical temperature of thermal explosion 342.2 °C, high apparent activation energy of 512.23 kJ•mol−1 and low sensitivity toward destructive mechanical stimuli (IS > 60J; FS > 360N), is promising candidate as gas generator.

Additional file 1. Supplemental tables and figures.

A trifluoromethyl-containing fused triazole-triazine energetic molecule, 3-nitro-7-(trifluoromethyl)-1,2,4-triazolo[5,1-c]-1,2,4-triazin-4-amine (TFX), has been synthesized in three steps from amino guanidine bicarbonate and trifluoroacetic acid. The process was found to be effective, nontoxic, and simple. The X-ray structure analysis of TFX finds that there are inter- and intramolecular hydrogen bonds and π–π interactions in the crystal lattice. TFX with a high density (1.88 g·cm–3) at room temperature, excellent thermal stability (Tp = 300.3 °C), moderate energetic performance, and with insensitivity to mechanical stimulation has potential as heat-resistant energetic materials.

Primary hepatic neuroendocrine carcinoma (PHNEC) manifests as a rare type of liver tumor. PHNEC is not specifically clinical or radiographical and is often misdiagnosed and mistreated. Here, we present a case report of PHNEC in a 50-year-old woman who was admitted to our department with concealed pain in the right upper abdomen. The initial diagnosis was a probable hepatic space-occupying lesion with tumor bleeding. The patient was subjected to a partial right hemihepatectomy, cholecystectomy, partial resection of the lower lobe of the right lung, partial resection of the diaphragm, and resection of the right perirenal fat sac to alleviate her symptoms. After surgery, gene sequencing was performed to determine the possible cause of the condition. However, five months after discharge, the patient was hospitalized again because of retroperitoneal and peritoneal multiple metastases. Nine months after surgery, the patient died. This case is likely to aid in furthering our understanding of PHNEC to improve the future diagnosis and treatment of this disease.

The concentration dependence of amplified spontaneous emission (ASE) and lasing characteristics in the blend of blue emitting poly(9,9-dioctylfluorene) (PFO) and ladder-type poly(indenofluorene) (2...

The surface functionalization of graphene oxide (GO) is always attractive in improving certain properties of the polymer. In this study, 3-aminopropyltriethoxysilane (APTES) and 3-mercaptopropyl-trimethoxysilane (SPTES) have been used to make silane functionalized graphene oxides (SiGOs). The APTES-grafted GO (NH-SiGO), SPTES-grafted GO (SH-SiGO) and pure GO have been separately introduced into the nitrocellulose (NC) matrix. The morphology, thermal properties and energetic properties of the prepared nanocomposites (NH-SiGO and SH-SiGO) were investigated comprehensively. It is shown that the presence of GO and SiGOs have different influences on the thermal reactivity of NC with various contents, and NH-SiGO with 0.5 wt% content showed better catalytic performance on the thermal decomposition of NC than others and showed prominently higher efficiency in improving its heat of combustion. Adding 0.5 wt% of NH-SiGO to NC may decrease its decomposition temperature from 202.1 °C to 196.6 °C, and the residue was decreased from 10.61 wt% to 3.95 wt%, respectively. One isoconversional kinetic method was exploited to determine the kinetic parameters of NC and its nanocomposites. It was found that NH-SiGO had a strong catalytic action on the thermal decomposition of NC-based nanocomposites for which the activation energy and the pre-exponential factor were considerably lowered, while SH-SiGO exhibited an inverse effect. The heat of combustion from NC/GO/0.5, NC/NH-SiGO/0.5 and NC/SH-SiGO/0.5 were determined as 11 249.5, 11 675.1 and 11 491.5 J g−1, respectively, which are higher than that of the pure NC (10 908.4 J g−1). From the combustion process of NC/NH-SiGO/0.5, it was shown that the nanocomposite was combusted completely.

Supplemental Material, sj-pdf-1-sri-10.1177_15533506211026411 for A Bibliometric Analysis of Overall and Top 100 Most-Cited Studies About Robotic Surgery Versus Open Surgery by Xiajing Chu, Peijing Yan, Na Zhang, Lufang Feng, Kangle Guo, Cuncun Lu, Tingting Lu, Chengbin Wang and Ke-hu Yang in Surgical Innovation

Supplemental Material, sj-pdf-1-sri-10.1177_15533506211026411 for A Bibliometric Analysis of Overall and Top 100 Most-Cited Studies About Robotic Surgery Versus Open Surgery by Xiajing Chu, Peijing Yan, Na Zhang, Lufang Feng, Kangle Guo, Cuncun Lu, Tingting Lu, Chengbin Wang and Ke-hu Yang in Surgical Innovation

In this study, Fe3O4/hyperbranched polyester-(2-dodecen-1-yl)succinic anhydride2-Dodecen-1-/isoniazid magnetic nanoparticles (Fe3O4/HBPE-DDSA/INH MNPs) with controlled drug release characteristics were synthesized successfully by a simple one-step method. Orthogonal experiments were performed to optimize the loading capacity and encapsulation efficiency of the MNPs. The structure of the Fe3O4/HBPE-DDSA/INH MNPs was characterized by 1H nuclear magnetic resonance spectroscopy, matrix-assisted laser desorption/ionization mass spectrometry, Fourier transform infrared spectroscopy, X-ray diffraction analysis, transmission electron microscopy, and superconducting quantum interference device measurements, while their properties were characterized based on swelling behavior observations, in-vitro release experiments, and cytotoxicity analysis. The results indicated that the fabricated Fe3O4/HBPE-DDSA/INH MNPs had a high drug-loading capacity and encapsulation efficiency. Further, the drug-release rate of the MNPs was higher in an acidic buffer, indicating that the MNPs were pH-responsive. Swelling studies revealed that the MNPs exhibited diffusion-controlled drug release, while in-vitro release studies revealed that the drug-release properties could be controlled readily, owing to the high encapsulation efficiency of the MNPs and the uniform dispersion of the drug in them. These results collectively suggest that this multifunctional nontoxic drug delivery system, which exhibits good magnetic properties and pH-triggered drug-release characteristics, should be suitable for the treatment of tuberculosis.

Face recognition based on few training samples is a challenging task. In daily applications, sufficient training samples may not be obtained and most of the gained training samples are in various illuminations and poses. Non-sufficient training samples could not effectively express various facial conditions, so the improvement of the face recognition rate under the non-sufficient training samples condition becomes a laborious mission. In our work, the facial pose pre-recognition (FPPR) model and the dual-dictionary sparse representation classification (DD-SRC) are proposed for face recognition. The FPPR model is based on the facial geometric characteristic and machine learning, dividing a testing sample into full-face and profile. Different poses in a single dictionary are influenced by each other, which leads to a low face recognition rate. The DD-SRC contains two dictionaries, full-face dictionary and profile dictionary, and is able to reduce the interference. After FPPR, the sample is processed by the DD-SRC to find the most similar one in training samples. The experimental results show the performance of the proposed algorithm on olivetti research laboratory (ORL) and face recognition technology (FERET) databases, and also reflect comparisons with SRC, linear regression classification (LRC), and two-phase test sample sparse representation (TPTSSR).

A family of starburst conjugated molecules composed of a pyrene core and diphenylamine end-cappers with various oligofluorene bridge lengths, named as P1F, P2F, and P3F, were designed, synthesized, and characterized. The resulting materials exhibited good photoluminescence (PL) properties and excellent thermal stability with high degradation temperatures (Td, the temperature with 5% weight loss) over 400 °C. A combination of the thermal, photophysical, electrochemical, fluorescence transients, electroluminescence (EL), amplified spontaneous emission (ASE), and lasing measurements were carried out to reveal further the influence of the diphenylamine moieties as electron-donating end-cappers on their optoelectronic properties. It is interesting to find that the PL spectra are significantly blue-shifted for P2F (∼11–15 nm) and P3F (∼14–22 nm) relative to those of P1F in both dilute solutions and films with an extension in the conjugation length of the oligofluorenes, which is quite different from the common ...

Herein, the photophysical, morphological, optical gain characteristics of a set of trigonal monodisperse starburst conjugated macromolecules (Tr1-Tr4) have been systematically investigated in order to elucidate the influence of the molecular structures on their optoelectronic performance. With increasing the oligofluorene arm length, absorption spectra were red-shifted progressively, whereas an increase in photoluminescence quantum yields (PLQYs) and optical gain coefficients, and a corresponding reduction in amplified spontaneous emission (ASE) thresholds and loss coefficients were observed for Tr1-Tr3 except for Tr4. The results indicate that the effective conjugation length become saturated for Tr3 in this system. Impressively, the resulting molecules manifested very low ASE thresholds (4.4-11.6 μJ cm-2 ) with high photostability, as well as high thermal stability. One dimensional distributed feedback (DFB) lasers exhibited a minimum lasing threshold of 10.38 nJ pulse-1 (0.86 kW cm-2 , 4.325 μJ cm-2 ) for Tr3. It should be emphasized that the ASE threshold of Tr1-Tr4 was nearly unchanged from room temperature to 200 °C. The results suggest that this kind of truxene-cored conjugated starbursts with high photostability and low lasing thresholds are rather promising gain media for organic semiconductor lasers.

A set of ladder-type poly(indenofluorene)s incorporating various indenofluorene chain lengths and 2,1,3-benzothiadiazole (BT) units, namely nLF-BT (n = 2–4), have been designed, synthesized and explored as gain media for organic lasers. The thermal, photophysical, electrochemical, electroluminescence, and optical gain properties of the resulting polymers have been systematically investigated in comparison with those of their poly(9,9-dioctylfluorene-co-benzothiadiazole) counterpart (F8BT) to unravel the structure–property relationships. It was found that with an extension of the ladder indenofluorene chain length the resulting copolymers exhibited progressively enhanced optical and electrical properties with low ASE thresholds, high net gain coefficients, and boosted device efficiency. The BT units played a key role in inducing energy transfer that further stabilized the optoelectronic properties of the resulting copolymers. Single-emissive-layer organic light-emitting devices based on nLF-BT exhibited superior maximum luminance and current efficiency in comparison with those of F8BT due to the incorporation of ladder-type indenofluorene chain structures. Solution-processed non-doped films exhibited prominent amplified spontaneous emission (ASE) and lasing characteristics. The ASE activity could still be detectable even upon annealing up to 280 °C for nLF-BT (n = 2–4). In particular, a relatively low ASE threshold of 6.04 μJ cm−2 with an emission peak at 568 nm and a high optical gain coefficient of g = 84 cm−1 were recorded for 4LF-BT. Moreover, one-dimensional (1D) distributed feedback (DFB) lasers based on 4LF-BT achieved a rather low lasing threshold of 7.2 nJ pulse−1 (0.60 kW cm−2, 3.0 μJ cm−2), showing great promise as robust gain media for organic lasers. These results suggest that the novel copolymer design strategy incorporating indenofluorene and BT units is rather attractive to construct robust gain media with promising low thresholds, high net gain coefficients, and stabilized lasing properties for organic lasers.

Cerebrovascular disease, hemiplegia and paraplegia may lead to lower extremity motor dysfunction. According to the theory of neural rehabilitation, proper rehabilitation training can help patients recover. In this paper, a lower limb rehabilitation robot is proposed, which can realize passive training and active training. Firstly, the mechanical structure and electrical system are designed. Secondly, in order to solve the problem of inaccurate parameters in the dynamic model of robot joint torque control, a fuzzy adaptive PID controller is established by combining negative feedback with PID regulator to eliminate the system error.

A series of monodisperse six-armed conjugated starbursts (Tr1F, Tr2F, and Tr3F) containing a truxene core and multibranched oligofluorene bridges capped with diphenylamine (DPA) units has been designed, synthesized, and investigated as robust gain media for organic semiconductor lasers (OSLs). The influence of electron-rich DPA end groups on their optoelectronic characteristics has been discussed at length. DPA cappers effectively raise HOMO levels of the starbursts, thus enhancing the hole injection and transport ability. Solution-processed electroluminescence devices based on the resulting six-armed starbursts exhibited efficient deep-blue electroluminescence with clear reduced turn-on voltages (3.2-3.5 V). Moreover, the resulting six-armed molecules showed stabilized electroluminescence and amplified spontaneous emission with low thresholds (27.4-63.9 nJ pulse-1 ), high net gain coefficients (80.1-101.3 cm-1 ), and small optical loss (2.6-4.4 cm-1 ). Distributed feedback OSLs made from Tr3F exhibited a low lasing threshold of 0.31 kW cm-2 (at 465 nm). The results suggest that the construction of truxene-centered six-armed conjugated starbursts with the incorporation of DPA units can effectively enhance EL properties by precisely regulating the HOMO energy levels, and further optimizing their optical gain properties.

This study reports the synthesis and characterization of a novel azido ester plasticizer, 3-azido-2,2-bis(azidomethyl)propyl 2-azidoacetate (ABAMPA), with good yield and high purity. The density, impact sensitivity, friction sensitivity, thermal decomposition temperature and glass transition temperature were determined to be 1.326 g ⋅ cm-3 , 16 J, 324 N, 235.9 °C and -50.4 °C, respectively. The plasticizing effect of ABAMPA on glycidyl azide polymer (GAP) was calculated by molecular dynamics, the solubility parameter difference value was 1.7(J ⋅ cm-3 )0.5 , and the glass transition temperature of GAP was reduced from -35 °C to -43 °C when the weight ratio of ABAMPA and GAP was 50 : 50. The new azido ester exhibits high energy, remarkable thermostability and good compatibility with GAP, which indicates that it would have potential application in explosive and propellant formulations.

Resistance towards imatinib (IM) remains troublesome in treating many chronic myeloid leukemia (CML) patients. Heme oxygenase-1 (HO-1) is a key enzyme of antioxidative metabolism in association with cell resistance to apoptosis. Our previous studies have shown that overexpression of HO-1 resulted in resistance development to IM in CML cells, while the mechanism remains unclear. In the current study, the IM-resistant CML cells K562R indicated upregulation of some of the histone deacetylases (HDACs) compared with K562 cells. Therefore, we herein postulated HO-1 was associated with HDACs. Silencing HO-1 expression in K562R cells inhibited the expression of some HDACs, and the sensitivity to IM was increased. K562 cells transfected with HO-1 resisted IM and underwent obvious some HDACs. These findings related to the inhibitory effects of high HO-1 expression on the reactive oxygen species (ROS) signaling pathway that negatively regulated HDACs. Increased expression of HO-1 activated HDACs by inhibiting ROS production. In summary, HO-1, which is involved in the development of drug resistance in CML cells by regulating the expression of HDACs, is probably a novel target for improving CML therapy.

A new method of array configuration for solar tracking photovoltaic (PV) devices is proposed. By analyzing the affecting factors of shadows, a calculation model of PV cell panels’ shadow in the sunlight is structured. And the variation rule of shadows in a year is founded by simulation program. Then a spacing calculation method of the solar tracking device array is proposed. The experiment result shows that the proposed method can minimize the installation spacing of PV device by ensuring PV cell panels without shadow shading and save area effectively in PV power station construction.

In order to study the secondary arc characteristics of single-phase transient fault in UHV transmission lines with hybrid reactive compensation, a transmission line electromagnetic coupling model is presented in this paper. Dynamic model of secondary arc was established on the basis of improved Mayer equation. Based on the transient simulation and the method of Laplace transform the law of secondary arc characteristics in UHV transmission lines with hybrid reactive compensation was obtained. With different compensation degrees of series compensation and controlled shunt reactor, as well as ground fault location, we can find secondary arc current almost increases linearly with the increase of series compensation degree and decreases linearly and then increases with the increase of the controlled shunt reactor compensation degrees. Based on the specific compensation device configuration scheme, a time sequential control strategy between the bypass switch and single-phase autoreclosure were given, which will provide a theoretical guidance for practical application.

Craters are among the most studied geomorphic features in the Solar System because they yield important information about the past and present geological processes and provide information about the relative ages of observed geologic formations. We present a method for automatic crater detection using advanced machine learning to deal with the large amount of satellite imagery collected. The challenge of automatically detecting craters comes from their is complex surface because their shape erodes over time to blend into the surface. Bandeira provided a seminal dataset that embodied this challenge that is still an unsolved pattern recognition problem to this day. There has been work to solve this challenge based on extracting shape and contrast features and then applying classification models on those features. The limiting factor in this existing work is the use of hand crafted filters on the image such as Gabor or Sobel filters or Haar features. These hand crafted methods rely on domain knowledge to construct. We would like to learn the optimal filters and features based on training examples. In order to dynamically learn filters and features we look to Convolutional Neural Networks (CNNs) which have shown their dominance in computer vision. The power of CNNs is that they can learn image filters which generate features for high accuracy classification., Comment: 2 Pages. Submitted to 47th Lunar and Planetary Science Conference (LPSC 2016)

In this paper a method of routing of clock distribution circuits will be presented. We first give out the background of the problem we later studied. In this section, we discuss the three constrains of the routing on a clock distribution chip. Then we offer an algorithm to solve this problem. The algorithm features in 3 steps, which are called topology generation, cut line generation and the adjustment process. We will further develop the 3 steps into more details in the following 3 sections. And in latter part some application samples are shown to evaluate the algorithm. Finally we concluded the further work we should probe into.

We quantify the Fisher information content of the cosmic shear survey two-point function as a function of noise and resolution. The two point information of dark matter saturates at the trans-linear scale. We investigate the impact of non-linear non-Gaussianity on the information content for lensing, which probes the same dark matter. To do so we heavily utilize N-body simulations in order to probe accurately the non-linear regime. While we find that even in a perfect survey, there is no clear saturation scale, we observe that non-linear growth induced non-Gaussianity could lead to a factor of ~4 reduction for the common Dark Energy figure of merit. This effect is however mitigated by realistic levels of shot noise and we find that for future surveys, the effect is closer to a factor of 1.5. To do so, we develop a new scheme to compute the relevant covariant matrix. It leads us to claim an unbiased estimator with an order of magnitude improvement in accuracy with only twice more simulations than previously used. Finally, we evaluate the error on the errors using bootstrap methods., Comment: submitted to PRD