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Enhancing the thermal decomposition efficiency and safety of ammonium perchlorate (AP) is of far‐reaching significance in composite propellants. Most catalysts act well on the thermal decomposition of AP, however, synergistically achievements of fastened decomposition and improved mechanical safety are still in challenge. Herein, neutral red (NR) is selected from typical dyes through theoretical calculations, acting as an organic decoration of AP crystal with improved performances. Among the four organic dyes, NR demonstrated the highest adsorption energy and evident charge transfer at the interface. Following preparations through a freeze‐drying technique obtained a quasi‐homogeneous energetic composite (NR‐AP‐5%). The large interaction force between NR and AP promoted the rupture of chemical bonds between Cl and O as proved by TG‐MS, showing excellent energy‐release performance with the decreased exothermic peak from 437.0 to 355.5 °C. Correspondingly, the activation energy is reduced from 213.59 to 107.72 kJ mol−1, with largely increased heat release from 447.29 to 1014.86 J g−1. In addition, the inert decoration of NR endowed considerable advances in the safety performances of AP, achieving remarkably improved impact and friction sensitivity of 35 J and 288 N, respectively. This unique assembly structure provides a novel strategy to achieve high‐effective catalysis for functional propellants. [ABSTRACT FROM AUTHOR]

The off-axis three-mirror anastigmatic (TMA) optical system has the advantages of eliminating all primary aberrations, having no aperture obscuration, no chromatic aberration, and good environmental adaptability, making it essential in high-performance optical instruments. Freeform surfaces, with their rich degrees of freedom (DOFs) in mathematical representation, positively affect the image quality and sensitivity of optical systems. When applied correctly to off-axis TMA optical systems, they can achieve fast F -numbers, large fields of view (FOVs), and long focal lengths. There are dozens of configurations for off-axis TMA optical systems, and freeform surfaces can be combined in numerous ways within these systems. This paper first analyzes the sensitivity of off-axis TMA optical systems with different configurations, selects the configuration with the lowest sensitivity, and combines it with a low sensitivity freeform surface combination to achieve high-performance freeform off-axis TMA optical systems with low sensitivity. [ABSTRACT FROM AUTHOR]

Melt-cast explosives are the most widely used energetic materials in military composite explosives, researchers have been unremittingly exploring high-energy and insensitive melt-cast explosives. In this work, a series of dinitrophenyl-oxadiazole compounds were designed and prepared. These compounds have an ideal low melting point (80–97 °C), good detonation performance (detonation velocity D = 6455–6971 m/s, detonation pressure P = 18–19 GPa) and extreme insensitive nature (impact sensitivity ≥60 J, friction sensitivity >360 N). All these compounds were well characterized by nuclear magnetic resonance, fourier transform infrared spectroscopy, elemental analysis. Compounds 2, 3 were unambiguously confirmed by X-ray single crystal diffraction analysis. As a result, their overall properties are superior to traditional melt-cast explosives trinitrotoluene (TNT) and dinitroanisole (DNAN) which may have excellent potential applications in insensitive melt-cast explosives.

For the linear multivariable systems, by combining both merits of orthogonal-function approach and evolutionary optimization, in this paper, a new method is presented for designing a Luenberger reduced-order observer to solve the low-sensitivity design issue for physical system parameter deviation and simultaneously to minimize a measurement of the quadratic performance for reducing state transient estimation error. Two given examples illustrate the effectiveness of the presented new low-sensitivity design approach on state estimation performance. From the given examples, it shows that the estimated state errors are not sensitive to system parameter deviation and have the asymptotical convergence property. Besides, the performances are apparently superior to those without considering low-sensitivity design means. [ABSTRACT FROM AUTHOR]

The off-axis three-mirror anastigmatic (TMA) optical system has the advantages of eliminating all primary aberrations, having no aperture obscuration, no chromatic aberration, and good environmental adaptability, making it essential in high-performance optical instruments. Freeform surfaces, with their rich degrees of freedom (DOFs) in mathematical representation, positively affect the image quality and sensitivity of optical systems. When applied correctly to off-axis TMA optical systems, they can achieve fast F-numbers, large fields of view (FOVs), and long focal lengths. There are dozens of configurations for off-axis TMA optical systems, and freeform surfaces can be combined in numerous ways within these systems. This paper first analyzes the sensitivity of off-axis TMA optical systems with different configurations, selects the configuration with the lowest sensitivity, and combines it with a low sensitivity freeform surface combination to achieve high-performance freeform off-axis TMA optical systems with low sensitivity.

Using commercially available raw materials, novel pyrimidine-based energetic compounds were synthesized, namely N-(7-oxo-6,7-dihydro-[1,2,5]oxadiazolo[3,4-d]pyrimidin-5-yl)nitramide (1), 2,4,6-triamino-5-nitropyrimidin-1-ium nitrate (2), and 4,6-diamino-5-nitro-2-oxo-2,3-dihydropyrimidin-1-ium nitrate (3). They were fully characterized using NMR (1H and 13C), IR spectroscopy, and elemental analysis. The crystal structures of compounds 1 and 3 were determined using single-crystal X-ray diffraction. The decomposition temperatures of compounds 1–3 were measured to be 190.2 ​°C, 156.8 ​°C, and 234.6 ​°C, respectively. Their densities were tested to be 1.84, 1.85 ​g ​cm−3, and 1.81 ​g ​cm−3, respectively. They exhibited desirable insensitive properties, with impact sensitivity ≥15 ​J and friction sensitivity >360 ​N. In addition, the detonation performances of compounds 1–3 were calculated with detonation pressure of 26.9, 29.6 ​GPa, and 26.0 ​GPa, respectively; detonation velocity of 8089, 8644 ​m ​s−1, and 7996 ​m ​s−1, respectively). Simple synthetic processes and high performance make them potential candidates for low-sensitivity energetic materials.

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Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the major challenges in the field of energetic materials is to develop explosive molecules with high detonation performances and low mechanical sensitivity. In this work, a heat-resistant and insensitive energetic compound 4-amino-7-nitro-5H-pyrazolo [4,3-d][1,2,3]triazine-2-oxide (3) was designed and prepared. It was identified and characterized using X-ray single-crystal diffraction, IR spectroscopy, NMR spectroscopy, mass spectrometry, thermogravimetry, differential scanning calorimetry (TG-DSC), and elemental analysis. This novel energetic compound exhibits good detonation performances (Dv ​= ​8731 ​m ​s−1, P ​= ​31.20 ​GPa), low mechanical sensitivities (IS ​> ​20 ​J, FS ​> ​360 ​N), and excellent thermal stability (Td ​= ​291 ​°C), suggesting that compound 3 may serve as a potential high-energy and insensitive material.

Incorporating amino groups is an efficient strategy for the tuning properties of energetic materials. However, there is no unanimous conclusion on the effect of the number of amino groups (−NH2) on performance. Therefore, in this study, different number of −NH2 of four energetic salts of triazolium based on oxadiazole and triazole were designed and synthesized. The structure features of energetic salts 4–6 were then investigated by single‐crystal X‐ray diffractions and Hirshfeld surfaces analyses. Afterward, the effects of −NH2 were evaluated by thermal stability, impact sensitivity and detonation performance. All these energetic salts were insensitive to mechanical stimulation (IS >40 J), but the thermal decomposition temperatures of energetic salt 5–7 with −NH2 are 24 °C to 54 °C higher than energetic salt 4 without −NH2. Moreover, energetic salt 5 with one −NH2 has the highest theoretical detonation properties compared to those without −NH2 (4) and with two −NH2 (6, 7). These observations revealed that appropriate amount of −NH2 can lead to desirable increase in the energetic properties, and this work can offer guidance for the design and synthesis of further energetic salts. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEN) is one of the most common contaminating mycotoxins and is mainly produced by Fusarium graminearum. ZEN and its metabolites can interfere with estrogen function and affect animals' reproductive ability. Pigs are most susceptible to ZEN, and ZEN is less harmful to poultry than to pigs. The exact mechanism for the difference in susceptibility remains unclear. In this review, we summarized some possible reasons for the relative insensitivity of poultry to ZEN, such as the lower total amount of α-zearalenol (α-ZOL) and the α-ZOL-to-β-ZOL ratio which reduce the toxicity of ZEN to poultry. The faster hepatic and enteric circulation, and excretion capacity in poultry can excrete more ZEN and its metabolites. There are other possible factors such as the transformation of intestinal microorganisms, differences in hydroxysteroid dehydrogenases' activity, high estrogen levels, and low estrogen receptors affinity which can also cause poultry to be relatively insensitive to ZEN. In this review, we summarized the hazards, pollution status, metabolic pathways, and some measures to mitigate ZEN's harmfulness. Specifically, we discussed the possible mechanisms of low reproductive toxicity by ZEN in poultry.

This paper uses a simple method to synthesis four guanidine salts of nitrophenols and tetrazoles with low sensitivity (friction sensitivity and impact sensitivity) and high decomposition temperature. The crystal structures were tested by an X-ray single crystal diffractometer. Thermal decomposition behaviors were examined via differential scanning calorimetry (DSC), revealing decomposition temperatures of 295.04 °C, 332.57 °C, 252.51 °C, and 301.17 °C, all exceeding 250.00 °C. The detonation velocities and pressures were calculated using Explo5 based on the experimentally measured combustion heat. The detonation velocities for the four guanidine salts followed the order 4 (7667 m s−1)＞ 2 (6909 m s−1)＞ 3 (6722 m s−1)＞ 1 (6560 m s−1), and the explosion pressures were ranked as 4 (19.13 GPa)＞ 2 (17.72 GPa)＞ 1 (14.96 GPa)＞ 3 (12.43 GPa). The combustion heats were measured using oxygen bomb calorimetry and were found to be 2 (11.85 kJ g⁻1) > 3 (11.66 kJ g⁻1) > 4 (11.31 kJ g⁻1) > 1 (10.57 kJ g⁻1). The impact sensitivity was greater than 100 J, and the friction sensitivity was greater than 360 N. Given these advantages, it is anticipated that these compounds could have applications in propellants and gas generators. [Display omitted] • Four guanidine salts of nitrophenols and tetrazoles with low sensitivity and high decomposition temperature were synthesized. • The crystal structures were tested by an X-single crystal diffractometer. • The combustion heats were tested through the oxygen bomb calorimetry, and their detonation performance (D and P) have been calculated. [ABSTRACT FROM AUTHOR]

The concept of the delta discrete‐time operator‐based doubly terminated two‐pair (ladder) is discussed here for use in sampled‐data and digital filter design. The two‐pair filter utilizes traditional backward Euler and forward Euler integrators, is lossless under scaling (LUS), and possesses good magnitude sensitivity which is induced intrinsically due to the filter structure. This paper is an overview and consolidation of results published by the authors over the years in various conferences (Khoo et al., 1998, 1999, 2001, 2008, 2008a, 2008b) in a unifying and tutorial fashion. To achieve the low magnitude sensitivity, the well‐known Feldtkeller equation corresponding to the delta‐operator formulation is derived to establish the theoretical basis for the realization. One significant advantage of the design procedure presented here using the delta operator is that it overcomes the numerical problem at the spectral factorization stage of the conventional z‐domain lossless‐discrete‐time integrator (LDI) synthesis method when the filter poles are clustered around z = 1. Furthermore, the entire operation involves only rational polynomials, as opposed to fractional power polynomials as in the LDI and other methods in z‐domain. The method presented can realize three distinct forms of transfer functions with varied transmission zeros. [ABSTRACT FROM AUTHOR]

Abstracts: Pentazolate anion (cyclo-N5−) containing compounds have attracted wide interest in recent years. In this paper, to explore the fantastic chemistry of cyclo-N5−, a novel polyamino 5/6/5-fused tricyclic-cation-based cyclo-N5− salt, 2,3,5,6-tetraamino-9-imino-5,9-dihydro-3H-bis([1,2,4]triazolo)[1,5-a:5′,1′-d][1,3,5]triazin-8-ium pentazol-1-ide (TABTT +N5−) was designed and synthesized. The chemical structures were determined by FTIR spectroscopy and single-crystal X-ray diffraction. TABTT +N5− exhibited a planar layer structure and a regular face-to-face layer stacking due to the strong hydrogen-bonding networks formed between polyamino 5/6/5-fused tricyclic and cyclo-N5−. TABTT +N5− exhibited acceptable thermal stability (Td: 106 ​°C), high density (1.638 ​g ​cm−3), high heat of formation (1078.122 ​kJ ​mol−1), and a good balance between energy and safety with high detonation performances (vD ​= ​8756 ​m ​s−1, p ​= ​26.03 ​GPa) and a low sensitivity (IS ​= ​25 ​J, FS ​= ​360 ​N), demonstrating the potential of nitrogen-rich cyclo-N5− salts as high energy materials.

In this study, a novel energetic compound 3-nitro-1-(2H-tetrazol-5-yl)-1H-pyrazole-4-carboxylic acid (1) and a series of corresponding energetic salts (2–4) were designed and synthesized. Their chemical structures were determined through NMR spectra, elemental analysis, FT-IR, and single crystal X-ray diffraction. All of these energetic compounds displayed low sensitivity to impact (IS ​> ​40 ​J) and friction (FS ​> ​240 ​N) and acceptable detonation properties. Compound 1–3 showed high thermal stability, with decomposition temperatures higher than 300 ​°C. In addition, the structure–property relationship of these compounds was elucidated by crystal stacking analyses combined with energetic performance parameters. In this way, a new approach for the development of novel energetic materials can be provided given the high performance of these energetic compounds.

The pyrotechnic compositions made up of potassium perchlorate (KClO4) and titanium hydride (TiH2), known as THKP, have a fast deflagration velocity (∼500 m/s), along with low sensitivity and high stability. In this research, a new kind of THKP was formulated from a submicron powder of KClO4 (50–400 nm) prepared by the Spray Flash‐Evaporation (SFE) process. The use of fine KClO4 not only ensures better oxidation of TiH2, but also leads to a transition to detonation in the THKP. This transition is observed in loose powders placed in small diameter tubes (3 mm). The distance of transition is relatively short (17–22 mm) and increases with the KClO4 content of the THKP mixture. The detonation front propagates steadily, at a velocity of ∼1250 m/s in THKP powders with 86 % of porosity. The shockwave velocity varies little with the perchlorate content in the domain of composition studied (55–74 wt.% of KClO4). Conversely, in the classical THKP mixtures prepared from micron‐sized KClO4 and tested in the same conditions, no transition to detonation is observed; the combustion slows down and eventually stops. Finally, owing to their high sensitivity thresholds to impact (SImp.≥44.7 J), friction (SFr.≥192 N), and electrostatic discharge (SESD≥34.7 mJ), THKP mixtures prepared from submicron KClO4 can be classified as low‐sensitivity primary explosives. [ABSTRACT FROM AUTHOR]

Two new types of aluminized explosives TATB/HMX/Al and LLM‐105/Al were formulated and compared with the formerly reported TATB/Al explosives in terms of thermal stability, mechanical sensitivity, and detonation performance. Firstly, the heat of the explosion was measured and two formulations were selected as the investigated samples. Next the thermal stability was studied by simultaneous thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) and thermal cook‐off tests. Then the impact and friction sensitivity were measured, and finally the detonation performance was characterized by cylinder tests and particle velocity measurements of the detonation reaction zone. From the calorimetric data, the new types of explosives increase the heat of the explosion significantly. In terms of thermal stability, LLM‐105/Al=65/30 is more stable than TATB/HMX/Al=50/15/30, but both of them are inferior to TATB/Al=70/25. The impact sensitivity of the two new explosives is higher than that of TATB/Al=70/25, and all of the samples are insensitive to friction. For detonation performance, both of the two new samples are superior to TATB/Al=70/25, and LLM‐105/Al=65/30 exhibits the best performance that it has the highest Gurney energy, detonation velocity, and detonation pressure. Conclusions about how to use those aluminized explosives to generate optimal effects are drawn. [ABSTRACT FROM AUTHOR]

In four-dimensional (4-D) light field (LF) processing, 4-D linear shift-invariant filters having hyperplanar passbands are used for depth-based scene enhancement. In this paper, two low-sensitivity and low-complexity field programmable gate array (FPGA)-based digital hardware architectures for 4-D hyperplanar filters are proposed for on-chip real-time processing of LFs. Both 4-D filters are designed exploiting resonant properties of multi-dimensional passive prototype networks, and are realized as wave digital filters (WDFs). The two 4-D WDF realizations are implemented as raster-scanned processing architectures on a Xilinx Virtex 6 Sx35 FPGA with a real-time clock speed of up to 33 MHz. This corresponds to a real-time throughout of 16.8 LFs/s for an LF of size 11 × 11 × 128 × 128 . [ABSTRACT FROM AUTHOR]

A low sensitivity and high workability of slump-retaining type polycarboxylate superplasticizer was obtained by using a new type 2+2 macromonomer-ethylene glycol monovinylpolyoxyether ether (EPEG), acrylic acid (AA), hydroxypropyl acrylate (HPA) and 2-acrylamide-2-methylpropane sulfonic acid (AMPS) as the main raw material, using a low temperature initiation system, through the aqueous solution of free radical polymerization. The optimal synthetic process conditions of polycarboxylate superplasticizer were explored through experiments. The results showed that when the initial reaction temperature was 20 °, the ratio of n (AA):n (EPEG) was 2.95, the ratio of n (HPA) :n (EPEG) was 2.25, the amount of sodium hydroxide was 0.75%, the amount of chain transfer agent was 1.2%,the amount of AMPS was 0.9%,and the dropping time of material A was 60 min, had the best dispersibility and retention performance. At the same time, compared with the conventional commercially available TPEG-type and HPEG-type polycarboxylate superplasticizer products, it had better workability, it was not easy to bleed, and had better slump retention performance. [ABSTRACT FROM AUTHOR]

The construction and modification of novel energetic frameworks to achieve an ideal balance between high energy density and good stability are a continuous pursuit for researchers. In this work, a fused [5,6,5]-tricyclic framework was utilized as the energetic host to encapsulate the oxidant molecules for the first time. A series of new pyridazine-based [5,6] and [5,6,5] fused polycyclic nitrogen-rich skeletons and their derivatives were designed and synthesized. Two strategies, amino oxidation and host-guest inclusion, were used to modify the skeleton in only one step. All compounds exhibit good comprehensive properties ( T d (onset) > 200 °C, ρ > 1.85 g cm -3 , D v > 8400 m s -1 , IS > 20 J, FS > 360 N). Benefiting from the pyridazine-based fused tricyclic structure with more hydrogen bonding units and larger conjugated systems, the first example of [5,6,5]-tricyclic host-guest energetic material triamino-9 H -pyrazolo[3,4- d ][1,2,4]triazolo[4,3- b ]pyridazine-diperchloric acid ( 10 ), shows high decomposition temperature ( T d (onset) = 336 °C), high density and heats of formation (ρ = 1.94 g cm -3 , Δ H f = 733.4 kJ mol -1 = 269 s), and low sensitivity (IS = 30 J, FS > 360 N). The comprehensive performance of D v = 8820 m s -1 , P = 36.2 GPa), high specific impulse ( I sp = 269 s), and low sensitivity (IS = 30 J, FS > 360 N). The comprehensive performance of 10 is superior to that of high-energy explosive RDX and heat-resistant explosives such as HNS and LLM-105. 10 has the potential to become a comprehensive advanced energetic material that simultaneously satisfies the requirements of high-energy and low-sensitivity explosives, heat-resistant explosives, and solid propellants. This work may give new insights into the construction and modification of a nitrogen-rich polycyclic framework and broaden the applications of fused polycyclic framework for the development of host-guest energetic materials.

In this study, based on two model nitramine compounds hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX) and octahydro‐1,3,5,7‐tetranitro‐1,3,5, 7‐tetrazocine (HMX), two series of new energetic molecules were designed by replacing carbon atoms in the ring with different amounts of boron atoms, their structures and performances were investigated theoretically by the density functional theory method. The results showed that the boron replacement could affect the molecular shape and electronic structure of RDX and HMX greatly, and then would do harm to the main performance like the heat of formation, density, and sensitivity. However, the compound RDX‐B2 is an exception; it was formed by replacing two boron atoms into the system of RDX and has the symmetric boat‐like structure. Its oxygen balance (4.9%), density (1.91 g/cm3), detonation velocity (8.85 km/s), and detonation pressure (36.9 GPa) are all higher than RDX. Furthermore, RDX‐B2 has shorter and stronger NNO2 bonds than RDX, making it possesses lower sensitivity (45 cm) and better thermal stability (the bond dissociation energy for the NNO2 bond is 204.7 kJ/mol) than RDX. Besides, RDX‐B1 and HMX‐B4 also have good overall performance; these three new molecules may be regarded as a new potential candidate for high energy density compounds. [ABSTRACT FROM AUTHOR]

A facile synthetic protocol was developed to synthesize unique energetic salts based on 4,6‐dihydrazino‐1,3,5‐triazine‐2‐one in good to high yield from commercial sources. The process was found to be practical and easily scalable. The resulting energetic compounds show good to excellent thermal stability with decomposition temperatures ranging from 180 °C to 331 °C. They possess low sensitivity to impact and friction (IS>20 J, FS>360 N), as well as positive enthalpy of formation (148.9∼1381.7 kJ mol−1). Their detonation velocity (VD) values locate between 8301 m s−1 and 9282 m s−1, and detonation pressure (P) values range from 26.1 GPa to 37.2 GPa, in some cases, which are comparable to those of HMX. From the view of sensitivity and energy level, some of the energetic compounds prepared in this work exhibit potential as insensitive excellent performance energetic materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Theoretical simulation was employed to select suitable conductive polymers for coating. • Three HMX/conductive polymer based composites were facilely prepared by in-situ polymerization. • The synergistic desensitization of impact and electrostatic spark was obtained. • Improved thermal phase stability with sluggish phase-transition kinetics was confirmed. Safety performance under external stimuli plays a crucial role for energetic materials. Therefore, desensitization of high explosive arouses widespread research interests in the field of energetic materials. Nevertheless, synergistically reducing impact and electrostatic spark sensitivities of 1,3,5,7-tetranittro-1,3,5,7-tetrazocane (HMX) remains challenging. Herein, a novel strategy concerning conductive polymer coating was proposed to solve this issue. Theoretically, the polypyrrole (PPy) can form a complete shell and strong interaction with HMX crystals. The HMX@PPy composite has been successfully achieved by in-situ polymerization, exhibiting superior sensitivities (impact: from 7 J to 27.5 J and electrostatic spark: from 0.4 J to 1.68 J) among reported HMX-based energetic materials. In addition, the thermal phase stability of HMX can also be visibly improved with sluggish phase-transition kinetics by introducing PPy coating. The current study provides a design concept for high energy explosives with low sensitivity and improved comprehensive performances. [ABSTRACT FROM AUTHOR]

The performance of the conventional adaptive beamformer undergoes degradation in the presence of the mutual coupling between the neighbouring elements. To eliminate the sensitivity for the MC, the dummy elements are fixed around the array. Here, the authors demonstrate the optimal layers of auxiliary elements for uniform rectangular array (URA) in the case of the specific MC model and give the concrete theoretical proof. The corresponding derivation proves that only one layer of auxiliary elements is needed to tackle with the MC effect, and the output SINR and beampattern are improved by means of the proposed method for URA. Finally, the simulation results have shown the effectiveness of authors’ method.

The performance of the conventional adaptive beamformer undergoes degradation in the presence of the mutual coupling between the neighbouring elements. To eliminate the sensitivity for the MC, the dummy elements are fixed around the array. Here, the authors demonstrate the optimal layers of auxiliary elements for uniform rectangular array (URA) in the case of the specific MC model and give the concrete theoretical proof. The corresponding derivation proves that only one layer of auxiliary elements is needed to tackle with the MC effect, and the output SINR and beampattern are improved by means of the proposed method for URA. Finally, the simulation results have shown the effectiveness of authors' method. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is an incurable malignancy often associated with primary and acquired resistance to therapeutic agents, such as proteasome inhibitors. However, the mechanisms underlying the proteasome inhibitor resistance are poorly understood. Here, we elucidate the mechanism of primary resistance to bortezomib and ixazomib in the MM cell lines, KMS-20, KMS-26, and KMS-28BM. We find that low bortezomib and ixazomib concentrations induce cell death in KMS-26 and KMS-28BM cells. However, high bortezomib and ixazomib concentrations induce cell death only in KMS-20 cells. During Gene Expression Omnibus analysis, KMS-20 cells exhibit high levels of expression of various genes, including anti-phospho-fibroblast growth factor receptor 1 (FGFR1), chemokine receptor type (CCR2), and serum and glucocorticoid regulated kinase (SGK)1. The SGK1 inhibitor enhances the cytotoxic effects of bortezomib and ixazomib; however, FGFR1 and CCR2 inhibitors do not show such effect in KMS-20 cells. Moreover, SGK1 activation induces the phosphorylation of NF-κB p65, and an NF-κB inhibitor enhances the sensitivity of KMS-20 cells to bortezomib and ixazomib. Additionally, high levels of expression of SGK1 and NF-κB p65 is associated with a low sensitivity to bortezomib and a poor prognosis in MM patients. These results indicate that the activation of the SGK1/NF-κB pathway correlates with a low sensitivity to bortezomib and ixazomib, and a combination of bortezomib and ixazomib with an SGK1 or NF-κB inhibitor may be involved in the treatment of MM via activation of the SGK1/NF-κB pathway.

Abstract The appearance of the nitrogen-rich energetic MOFs provides another opportunity for the new-generation of high energetic explosives. In this work, an insensitive energetic nitrogen-rich ligand, 3-amino-1, 2, 4-triazole (Hatz) was imported into the system of transition-metal azides via the coordination polymerization strategy in the hope to prepare mixed-ligand nitrogen-rich high energetic MOF materials with low sensitivity and finally a solvent-free 3D energetic compacted metal-organic framework (MOF), Cd 3 (atz) 4 (N 3 ) 2 ( 1 ) was successfully isolated under hydrothermal conditions. Compound 1 was characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis (EA), different scanning calorimetry (DSC), and thermogravimetry analysis (TGA). Topological analysis shows that the 3D framework of 1 can be abstracted into a ten-connected topological network. The volatile azido ion can be viewed as a counter anion to be stabilized in a 3D framework as the connection of Cd(II) ions with two independent atz− ligands still remains a 3D framework. Compound 1 has a high calculated density ( ρ ) of 2.517 g cm−3. The standard molar enthalpy of formation ( Δ f H o ) of 1 was calculated to be 1330.10 kJ mol−1, which is higher than those of most of the previously 3D energetic MOFs. Sensitivity tests demonstrate that 1 is insensitive to external mechanical stimuli. TGA demonstrates that 1 has an excellent thermostability which can be stable up to 372 °C. Compound 1 can be served as a high-energy-density material with a favorable level of safety due to its excellent energetic performances, low sensitivities and excellent thermostability. Graphical abstract Importing an insensitive energetic nitrogen-rich ligand, 3-amino-1, 2, 4-triazole (Hatz) into the system of transition-metal azides via the coordination polymerization strategy, a N-rich high energetic MOF material with low sensitivity, Cd 3 (atz) 4 (N 3 ) 2 was isolated. This compound has a high calculated density ( ρ ) of 2.517 g cm−3. The standard molar enthalpy of formation ( Δ f H o ) of this compound was calculated to be 1330.10 kJ mol−1, which is higher than those of most of the previously 3D energetic MOFs. fx1 Highlights • A nitrogen-rich high energetic 3D MOF, Cd 3 (atz) 4 (N 3 ) 2 , was successfully synthesized. • This MOF has a high calculated density of 2.517 g·cm−3 and can be stable up to 372 °C. • The volatile azido contained 3D MOF has a very high calculated molar enthalpy of formation of 1330.10 kJ·mol−1. [ABSTRACT FROM AUTHOR]

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Viral hemorrhagic septicemia virus (VHSV), causing severe diseases in farmed fish, is detected and genotyped using conventional reverse-transcription PCR (cRT-PCR) targeting the nucleoprotein gene with corresponding VN F (forward) and VN R (reverse) primers. However, these primers have low sensitivity to VHSV subtype IVa; I investigated the cause for the poor cRT-PCR performance using various primer combinations. The results demonstrated that a 3′-end mismatch in the VN F primer reduced sensitivity and plays a critical role in VHSV detection by cRT-PCR. [ABSTRACT FROM AUTHOR]

This paper presents a new methodology for synthesis of broadband matching networks based on Clonal Selection Algorithms (CSA). This metaheuristic uses the hypermutation as only variation operator resulting in a gradual evolving of the network topology. A closed form expression for the transducer power gain (TPG) sensitivity with respect to the component values is employed, in such a way that the effects of the components tolerance on the matching network performance can easily be quantified. The evolvable function proposed is single-objective and eliminates the difficult task of assigning appropriate weights to parameters. The evaluation of the TPG sensitivity enables the designer to identify and remove irrelevant components of the circuit, simplifying it. The efficiency of the methodology is tested in two cases found in the literature: the traditional project of impedance matching for a simple RLC load proposed by Fano [1]; and a real synthesis of impedance matching network for a monopole whip antenna, proposed in [2]. The results are compared with other existing methods. [ABSTRACT FROM PUBLISHER]

Intra-partum (IP) surveillance of the unborn child by cardiotacography (CTG) monitoring is the commonest obstetric procedure in the developed world.1 It is also the most medico-legally contested obstetric procedure in labour. In 2011, ‘birth asphyxia’ comprised 50% of the UK National Health Service (NHS) litigation costs,2 and in the 2000–2010 decade, the same NHS paid out £3.1 billion for maternity medico-legal claims (the highest of any speciality), mostly involving cerebral palsy and CTG misinterpretation.3 This article looks at a number of characteristics of IP CTG monitoring which argue for its questionable solidity of base in court proceedings. [ABSTRACT FROM AUTHOR]

• The microfluidic self-assembly technology is used to prepare insensitive high-energy explosives. • This method can achieve continuous, safe and large-scale preparation of composite energetic materials. • The prepared TATB/HMX composite particles have great safety performance and detonation properties. Recently, to prepare energetic materials (EMs) with high energy and low sensitivity has attracted much attention in the field of EMs research. However, the safe and efficient manners to prepare such EMs are still limited. In this work, a continuous microfluidic self-assembly method was developed to prepare TATB/HMX composite particles, which has great safety performances (H 50 = 64.6 cm, friction sensitivity = 0 %) and detonation properties (detonation velocity 8375 m/s, ρ = 1.780 g/cm3). The XRD and SEM results show that in-situ generated nano-TATB (mass fraction 10 %) is not only bonded to the surface of HMX, but also embed in the crystal. Furthermore, this method realizes the continuous and stable preparation of TATB/HMX composite particles within 80 min. We anticipate that this work will inspire new perspectives for the preparation of insensitive high-energy explosives. [ABSTRACT FROM AUTHOR]

Young sediments, with low sensitivity and low dose rates, are challenging for luminescence dating. Here, we present work on the site of Sandwick South, a Norse settlement, in which these challenges were present. Field gamma dose rates below 0.1 mGy a −1 , and total dose rates of 0.4–0.5 mGy a −1 , combined with expected ages of less than 1 ka, resulted in a requirement for quantitative determination of equivalent doses of 0.2–0.4 Gy. The bedrock geology of the area are metagabbros, which explain both the exceptionally low dose rates and the lack of autochthonous quartz. Luminescence profiling during fieldwork revealed stratigraphically progressive OSL and IRSL signals, indicating phases in the sediments with dating potential. While laboratory characterisation recovered some quartz, its low yields and luminescence sensitivity precluded application of quartz methods. Electron microscopy confirmed the presence of feldspars, which were separated and used for IRSL Single Aliquot Regeneration Additive (SARA) analysis. Counting times for both high resolution gamma spectrometry (HRGS) and thick source beta counting (TSBC) measurements were extended by 1 order of magnitude, resulting in overall uncertainties of <6% for these low dose rates. Dose estimates were obtained using an adapted SARA protocol, incorporating long overnight preheats before first measurement, with the aim of mitigating short-term fading effects. Using these procedures, archaeologically meaningful dates were obtained from this difficult material, which are internally consistent, coherent with stratigraphy, and concordant with the radiocarbon constraints of the associated archaeological settlement. The dates demonstrate sand accumulation in the early to mid-13th century AD and also in the 18th century AD, which are contemporary with disruptive sand movements registered in other coastal regions of the Northeast Atlantic and North Sea regions. The approaches adopted here have provided solutions to the challenging conditions of this young, insensitive material and can therefore be considered to extend the range and applicability of luminescence dating methods. [ABSTRACT FROM AUTHOR]

An all-digital sliding-mode (ADSM) controlled dc-dc converter, utilizing single-bit oversampled frequency domain digitizers in its feedback path is proposed. Sliding-mode control provides several benefits over the traditional PID control in terms of fast transient response, robustness to parameter and component variations, and low sensitivity to loop disturbances. However, analog implementations of sliding-mode control require several amplifiers in the controller and suffer from process, voltage, and temperature variations. In the proposed approach, the sliding-mode controller (SMC) is implemented digitally; utilizing a first order single-bit ΣΔ frequency to digital converter (ΣΔFDC)-based feedback and reference digitizing ADCs, running at 32-MHz sampling rate. The ADSM regulator achieves 1% settling time in less than 5 μs for a load variation of 600 mA. The SMC uses a high-bandwidth hysteretic differentiator and an integrator to perform the sliding control law in digital domain. The proposed approach overcomes the steady-state error (or dc offset), and band limits the switching frequency, which are the two common problems associated with SMCs. The IC is designed and fabricated on a 0.35-μm CMOS process occupying an active area of 2.72 mm2. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper presents two narrowband high-temperature superconducting (HTS) filters at 10 GHz with a 0.6% fractional bandwidth. Uniform impedance rectangular resonator (UIRR) and stepped impedance H-type resonator (SIHR) are proposed to achieve HTS filters with high Q value, low sensitivity, weak coupling, and good parasitic response. A six-pole HTS filter that has UIRRs with a Q value of 17,700 is fabricated; this filter has a 19.9 dB return loss and a 0.38 dB insertion loss. An eight-pole HTS filter that has SIHRs with a Q value of 12,100 is also manufactured; this filter has a 12.2 dB return loss and a 0.64 dB insertion loss. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1516-1520, 2014 [ABSTRACT FROM AUTHOR]

The introduction of azido groups into the energetic skeleton has the advantages of increasing the energy level. In this work, a series of azido compounds with good stability and low sensitivity as well as tetrazole-fused compounds based on energetic salts are synthesized. The detonation pressures and velocities of these new compounds fall in the ranges of 18.9-27.3 GPa and 7153-8450 m s -1 , respectively. The detonation velocity of the tetrazole-fused compounds based on the potassium salts 3 , 6 , and 7 are 7810, 7153, and 7989 m s -1 , respectively. Also, their decomposition temperatures (244, 237, and 240 °C, respectively) are higher than that of traditional explosive RDX (204 °C). Notably, two representative compounds 2 and 5 possess higher decomposition temperature ( 2 : 196 °C and 5 : 178 °C) and overall detonation properties ( 2 : D = 8129 m s -1 and P = 26.6 GPa and 5 : D = 8336 m s -1 and P = 27.3 GPa) as well as relativity lower sensitivities ( 2 : IS = 12 J and FS = 240 N and 5 : IS = 10 J and FS = 144 N) than that of primary explosive 2-diazo-4,6-dinitrophenol ( T d = 157 °C, D = 6900 m s -1 , P = 24.7 GPa, IS = 1 J, and FS = 24.7 N). Moreover, the initiation capacity of compounds 2 and 5 was also assessed through the initiation tests. The results indicate that the two compounds could be a promising environmentally friendly primary explosive.

Copyright of Automatika: Journal for Control, Measurement, Electronics, Computing & Communications is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • An energetic molecule (NTTD) was obtained by one-step reaction with high yield. • NTTD can act as a heat-resistant and insensitive explosive. • The reaction has many advantages, which are conducive to large-scale preparation. • The derivatives of NTTD were synthesized through simple derivatization reactions. Low cost, high yield, good safety, and simple synthesis process are the problems that must be solved in the engineering preparation of energetic compounds, even beyond the pursuit of high energy level to some extent. In this work, a novel 5,6-fused energetic molecule 2-nitro-[1,2,4]triazolo[1,5- a ][1,3,5] triazine-5,7-diamine (NTTD) was designed and easily obtained. By the introduction of oxidants (HNO 3 and HClO 4) and high-energy groups (–NHNO 2), the derivatives of NTTD were prepared, some of which exhibited good comprehensive properties. Importantly, NTTD features excellent thermostability and low mechanical sensitivities. The whole preparation process has advantages of simple operation, short time, cheap and simple reagents, good repeatability, and high yield, which are conducive to large-scale preparation, indicating that NTTD can be a potential candidate of heat-resistant and insensitive explosives. [ABSTRACT FROM AUTHOR]

• Two new nonmetallic pentazolate salts were synthesized by metathesis reaction and fully characterized. • Two compounds form layer-by-layer structures through π−π interactions. • Achieve a balance between good detonation performance and low sensitivities. The all-nitrogen cyclo-pentazolate (c -N 5 ˉ) anion has attracted interest because of its promising application in high-energy materials. Now, nonmetallic pentazolate salts were prepared by assembling cyclo-N 5 ˉ and cations but it was shown to be challenging to balance excellent detonation performance and good stability, which results in restrictions for practical applications. However, we find the layer-by-layer crystal stacking structure can enhance the sensitivity of pentazolate salts. Herein, we designed and synthesized two targeted cyclo-pentazolate salts with layered stacking mode in their crystal structures based on two isomeric cations: 3,4,5-triamino-1,2,4-triazolium and 3-hydrazino-4-amino-1,2,4-triazolium. The results demonstrate that the aromaticity of triazole and pentazole rings arouse the π−π interaction force, promoting the formation of a layer-by-layer crystal stacking structure. Two compounds show very low sensitivity characteristics (FS>40 and IS>360) and good detonation properties (detonation velocity: 3, Dv= 8796m⋅s−1; 4, Dv=8574m⋅s−1. detonation pressure: 3, P = 26.6 GPa; 4, P = 25.1 GPa). Computational analysis based on noncovalent interaction index, localized orbital locator-π and electron density difference provide a better understanding about the effects of layer-by-layer stacking structure on the stabilities. These findings contribute to preparation of both high-energy and low sensitivity pentazolate salts. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Automatika: Journal for Control, Measurement, Electronics, Computing & Communications is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A method of designing a state feedback gain achieving a specified insensitivity of the closed-loop trajectory by the singularly perturbed unified system using the d operators is proposed. The order of system is reduced by the singular perturbation technique by ignoring the fast mode in it. The proposed method takes care of the actual trajectory variations over the range of the singular perturbation parameter. Necessary conditions for optimality are also derived. The previous study was done in the continuous time system. The present paper extends the previous study to the discrete system and the d -operating system that unifies the continuous and discrete systems. Advantages of the proposed method are shown in the numerical example. [ABSTRACT FROM AUTHOR]

Background Cyto-histological diagnosis of pancreatic pathology in the management of suspected pancreatic malignancy is re-evaluated in the light of evolving trends in management and tissue sampling. Methods The literature on cyto-histological diagnosis of pancreatic pathology was reviewed over the period 1977-2003. Results and conclusion Endoluminal techniques of tissue sampling carry less risk of tumour seeding and are the sampling methods of choice for potentially resectable lesions if a tissue diagnosis will alter therapy. Endosonar-guided biopsy in expert hands appears to be the most reliable tissue sampling technique. Transcoelomic sampling methods should be reserved for those with unresectable disease. All methods of cyto-histological diagnosis have high specificity but have a low negative predictive value. Therefore, potentially resectable lesions that are highly suspicious for malignancy should be explored even if preoperative histology or cytology is negative. [ABSTRACT FROM AUTHOR]

Filling at physiological rates (natural filling) is the specific stimulus for activation of the micturition reflex. In urodynamic studies this has rarely been taken into consideration. In the vast majority of clinical urodynamic studies 50 ml/min has been the preferred filling rate. A comparative study in 17 healthy volunteers of cystometry at 50 and 100 ml/min (CMG) and ambulatory monitoring (AM) during natural filling has been performed by other authors (3). It was found that CMG increases volume threshold for micturition, impairs detrusor contractility and has lower sensitivity for detecting spontaneous phasic detrusor activity. These results are discussed in the present article. The nearest explanation is at the cellular level. Filling rates above physiological range (>15 HD (Hour-Diuresis units)) are a mechanical trauma to receptors, nerve endings, cells and cell junctions, which are temporarily functionally disturbed. [ABSTRACT FROM AUTHOR]