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Recent years have witnessed significant advancements in methodologies and techniques for the synthesis of energetic materials, which are expected to shape future manufacturing and applications. Techniques including continuous flow chemistry, electrochemical synthesis, microwave-assisted synthesis, and biosynthesis have been extensively employed in the pharmaceutical and fine chemical industries and, gratifyingly, have found broader applications. This review comprehensively introduces recent advancements in the utilization of these emerging techniques, aiming to provide a catalyst for the development of novel green methods and techniques for synthesizing energetic materials.

To understand the nano effect on the thermal decomposition of cocrystal explosives, this study simulated the initial decomposition of cocrystal BTF/TNB nanoparticles (NPs) with diameters of 2.2–3.0 ​nm at high temperatures of 2400–3000 ​K using density functional tight-binding molecular dynamics (DFTB-MD) with dispersion corrections. As indicated by the simulation results, the volume expansion of the nanoparticles competed with its decomposition, and smaller nanoparticles promoted the diffusion of the molecules and products in the nanoparticles. Moreover, the nanoparticles had a higher decomposition rate at higher temperatures, and smaller nanoparticles were associated with a higher decomposition rate and weaker interactions between intermediates and lattice. The number of clusters first increased and then decreased during the decomposition of the nanoparticles. The results of this study may help in understanding the effects of temperature and particle size on the thermal decomposition mechanisms of cocrystal explosives.

The thermal decomposition processes of CL-20 nanoparticle (NP), core-shell structured CL-20@Al NP, and CL-20@AlO NP were studied through reactive molecular dynamics simulations. The results are as follows: (1) the CL-20@Al and CL-20@AlO NPs decomposed earlier than the CL-20 NP; (2) the Al shell experienced the melting-aggregation process and gradually changed from a shell structure to block aluminized clusters; (3) different in the decomposition of the CL-20 NP, N2 appeared first in the decomposition of the CL-20@Al and CL-20@AlO NPs, indicating that Al changed the initial decomposition process of CL-20; (4) the quantities of NO2, NO, and CO2 produced during the decompositions of the CL-20@Al and CL-20@AlO NPs were much lower than those produced during the decomposition of CL-20 NP. This occurred because the Al atoms had high activity at high temperature and attacked these products to produce massive aluminized substances; (5) Al significantly promoted the movement of H and N atoms but impeded that of O and C atoms in the three systems. This study will present fundamental information about the interfacial behaviors of aluminized explosives.

Abstract Background Neck pain and cervical disc degeneration (CDD) are common findings. Valid data on correlation between clinical scores and radiological grade of CDD in patients with mild to moderate clinical disability are not available. The study has been designed to investigate the correlation between clinical and radiological outcomes in these patients. Methods A cohort of 150 patients who suffered from mild to moderate cervical spine dysfunction symptoms from September 2020 to May 2021 was enrolled. We evaluated functional status using Japanese Orthopaedic Association scores (JOA), the visual analog scale, and the Neck Disability Index. We assessed the CDD with magnetic resonance imaging-based grading systems. We analyzed relationships between radiological grades of CDD and clinical symptoms along with demographic data. Results One hundred thirteen patients [mean age 44.78, 78 (69%) females] were finally included. CDD occurred most at the C5–C6 level, with 56.93% of higher grade III from Miyazaki. The grades of Miyazaki (P

As a necessary tool for understanding, prediction, and design (especially on a microscopic scale), Quantum chemical (QC) methods have a profound impact on the field of energetic materials (EMs). This study focuses upon the QC methods applicable to energetic molecules and their related applications. They generally include the Hartree-Fock method, semi-empirical QC methods, density functional theory (DFT), and high-accuracy ab initio methods. This study includes a detailed discussion about the application scope and accuracy of the descriptions of the geometric structure, electronic structure, thermodynamic property, and reactivity of energetic molecules. Additionally, this study stresses machine learning combined with DFT calculations that becomes increasingly popular as an important way to establish models for accurate property predictions. This work is expected to be instructive and constructive for the use of QC methods in EM study.

In this study, based on two attractive energetic compounds pentazole (PZ) and tetraazacubane (TAC), a new family of high energy and high nitrogen compounds pentazolyltetraazacubanes were designed. Then, a different number of NH2 or NO2 groups were introduced into the system to further adjust the property. The structures, properties, and the structure-property relationship of designed molecules were investigated theoretically. The results showed that all nine designed compounds have extremely high heat of formation (HOF, 1226-2734 kJ/mol), good density (1.73–1.88 g/cm3), high detonation velocity (8.30–9.35 km/s), high detonation pressure (29.8–39.7 GPa) and acceptable sensitivity (ΔV: 41-87 Å3). These properties could be effectively positive adjusted by replacing one or two PZ rings by NH2 or/and NO2 groups, especially for the energy and sensitivity performance, which were increased and decreased obviously, respectively. As a result, two designed pentazolyltetraazacubanes were predicted to have higher energy and lower sensitivity than the famous high energy compound in use 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, while two others have better combination property than 1,3,5-Trinitro-1,3,5-triazacyclohexane. In all, four new pentazolyltetraazacubanes with good combination performance were successfully designed by combining PZ with TAC, and the further property adjustment strategy of introducing a suitable amount of NH2/NO2 groups into the system. This work may help develop new cage energetic compounds.

Actions and priorities to connect the global community of plant scientists with the world’s changing societies are today more imperative than ever. Environmental degradation, unsustainable resource use, and biodiversity loss all require integrated, collaborative solutions.

The title pyrrole derivative compound, C12H17NO4, was synthesized from methyl 3-oxopentanoate by a Knorr-type reaction and contains a pyrrole ring to which two diagonal alkoxycarbonyl groups and two diagonal alkyl substituents are attached. The methylcarbonyl and ethylcarbonyl substituents are approximately co-planar with the pyrrole ring, making dihedral angles of 5.64 (2) and 3.44 (1)°, respectively. In the crystal, adjacent molecules are assembled by pairs of N—H...O hydrogen bonds into dimers in a head-to-head mode.

The title pyrrole derivative, C12H17NO4, consists of a pyrrole ring with two diagonally attached methoxycarbonyl groups and two diagonally attached ethyl groups. The two carbonyl groups are approximately in the same plane as the pyrrole ring, making dihedral angles of 3.50 (19) and 6.70 (19)°. In the crystal, adjacent molecules are assembled into dimers in a head-to-head mode by pairs of intermolecular N—H...O hydrogen bonds.

The properties of the low-sensitivity explosive trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin (TNAD)-based polymer-bonded explosives (PBXs) with four typical fluorine polymers are studied by using the molecular dynamics simulations. The results reveal that the addition of small amounts of fluorine polymers improves the mechanical properties of TNAD, whereas the detonation performances of the PBXs decrease.

The B3LYP/6-31G method is employed to evaluate the heats of formation (HOFs) for polynitrohexaazaadamantanes by designing isodesmic reactions. The HOFs are found to be correlative with the number and the space orientations of nitro groups.

In this work, NH2-substituted oxazoles and NO2/NF2/NHNO2-substituted ethylenes/acetylenes were designed and used as dienes and dienophiles, respectively, in order to develop new bridge-ring insensitive high energy compounds through the Diels-Alder reaction between them. The reaction type, reaction feasibility and performance of reaction products were investigated in detail theoretically. The results showed that dienes most possibly react with dienophiles through the HOMO-diene controlled normal Diels-Alder reaction at relatively low energy barrier. Tetranitroethylene could react with the designed dienes much more easily than other dienophiles, and was employed to further design 29 new bridge-ring energetic compounds. Due to high heat of formation, density and oxygen balance, all designed bridge-ring energetic compounds have outstanding detonation performance, 16 of them have higher energy than HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocine) and 2 others even possess comparative energy with the representative of high energy compounds CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12- hexaazaisowurtzitane). The predicted average h50 value of these bridge-ring energetic compounds is 83 cm, showing their low impact sensitivity. The NH2 groups could obviously impel the proceeding of Diels-Alder reactions, but would slightly decrease the energy and sensitivity performance. In all, the new designed bridge-ring compounds have both high energy and low sensitivity, and may be produced through Diels-Alder reactions at relatively low energy barrier. This paper may be helpful for the theoretical design and experiment synthesis of new advanced insensitive high energy compounds. [ABSTRACT FROM AUTHOR]

The structural, electronic and mechanical properties of the energetic material bicyclo-HMX are studied by using density functional theory and molecular dynamics. The increase of temperature has not changed the crystal structure and the thermal expansion coefficients have shown anisotropic behavior with slightly larger expansion along the a- and c-axes than along the b-axis.

DFT/B3LYP, natural bond orbital (NBO) and Bader's theory of atoms in molecules (AIM) are employed to investigate structural, dielectric and vibrational properties of the cis-triazidine clusters up to eight molecules and their strengths of N...H H-bonds and nonadditive interaction energies. Investigation revealed that cooperative phenomenon is pervasive in the clusters, as reflected in changes in N...H lengths, N-H stretching frequencies and intensities, dipole moments and charge transfers with increasing cluster size.

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We report the case of a six-year-old boy who presented with cardiogenic shock due to Kawasaki disease (KD). He was misdiagnosed at first as septic shock. After careful examination, he was diagnosed as KD complicated with acute coronary syndrome, which leads to cardiogenic shock. Cardiogenic shock is often neglected as a complication of KD, and it tends to be misdiagnosed. We hereby call attention to KD, in some cases of which, it can lead to acute coronary syndrome in the acute phase. [ABSTRACT FROM AUTHOR]

Purpose : To investigate CYP17A1 gene mutations in Chinese patients with 17 α -hydroxylase deficiency. Methods : Clinical data were retrospectively analyzed. CYP17A1 mutations were detected in two cases with 17 α - hydroxylase deficiency. Genomic DNA was isolated from blood samples and eight primers pairs were used to amplify eight exons and exon - intron boundaries of the CYP17A1 gene. The amplified PCR products were purified by agarose gel electrophoresis and then directly sequenced. Sequencing results were compared to the established human CYP17A1 sequence. Results : Two compound mutations were identified: TAC ? AA at codons 436 - 438 on exon 6, causing the amino acid missense mutation Y329K/418X; and deletion of the 9-bp sequence GACTCTTTC at codons 487 - 489 on exon 8, causing deletion of three amino acids (Asp-Ser-Phe). Conclusion : D487_F489del and Y329K, 418X CYP17A1 mutations were identified in our two patients. A literature review revealed that the main CYP17A1 mutations in the Chinese population are missense and splicing defects, and exons 8 and 6 are most frequently involved. [ABSTRACT FROM AUTHOR]

Three new copper(ii) complexes of N-benzyl di(pyridylmethyl)amine (phdpa) were synthesized and characterized by spectroscopic methods. The interaction between CT–DNA and the complexes was studied by UV and fluorescence titration methods. It was found that the complex [(phdpa)Cu(H2O)Ac)](Ac), with the non-planar aromatic heterocyclic ring ligand (phdpa), showed good anticancer properties and could cause the fragmentation of the nucleus, although its interaction with CT–DNA was weaker than that of 1,10-phenanthroline (phen) -based copper(ii) complexes. The anticancer activities of copper(ii) complexes with phdpa and phen based ligands are correlated to their binding constants with DNA, but phen-based copper(ii) complexes did not cause the nucleus fragmentation of HeLa cells. [(phdpa)Cu(H2O)Ac)](Ac) can noticeably decrease the oxygen content of a culture solution and of HeLa cells, which make it a new nucleus and oxygen related anticancer copper(ii) complex. Information obtained here would be helpful in the design of new antitumor complexes in oxidative therapy. [ABSTRACT FROM AUTHOR]

Background: Smoking cessation programs are well established in the West, but reports on smoking cessation clinics (SCCs) from China are lacking. On the basis of the Hong Kong experience and with strong support from Guangzhou Health Bureau, we established the first SCC in Guangzhou, China. The objective was to describe the characteristics of smokers, measure quit rates and examine predictors of successful quitting. [ABSTRACT FROM PUBLISHER]

The article presents a study on the alternative splicing and characterization of the enzyme Complex I 19-kD subunit in Dunaliella salina (D. salina). The study isolates the four splice variants and genomic sequence from D. salina, which encode the complex I 19-kD subunit and examines the splicing pattern of the D. salina 19-kD subunits. Polymerase chain reaction (PCR) shows that 19-kD subunit gene in D. Salina was expressed as multiple alternatively spliced isoforms in different stresses.

Based on density functional theory (DFT), four different methods with the generalized gradient approximation (GGA) have been employed to investigate the structural and electronic properties of the four polymorphs (·H2O, , , and phases) of CL-20, which is a well-known high energy density compound (HEDC). The relaxed crystal structures compare well with experimental data. According to the constitution of the frontier energy bands and the Mulliken population analyses, the N−NO2bond is predicted to be the trigger bond during thermolysis. The density of states (DOS) of -CL-20·H2O is somewhat different from those of the other three crystals for its inclusion of H2O molecules that contribute the frontier energy bands. The band gaps obtained from the four different methods are consistent with each other. According to the calculated values of band gaps, the sensitivity of the four polymorphs of CL-20 is predicted as < < < ·H2O, which agrees well with the experimental result. The effects of hydrostatic compression on the most stable -CL-20 have also been investigated using the GGA-PBE method in the pressure range of 0−400 GPa. -CL-20 has anisotropic compressibility at low or high pressure. The band gap is found to decease with increasing pressure, showing the corresponding sensitivity increase. Based on the changes of the band gap and DOS with pressure, 400 GPa is considered to be the critical pressure for the insulator−metal phase transition. [ABSTRACT FROM AUTHOR]

The theoretical linear solvation energy relationship (TLSER) approach was adopted to predict the aqueous solubility and n-octanol/water partition coefficient of three groups of environmentally important chemicals-polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins and dibenzofurans (PCDDs and PCDFS). For each compound, five quantum parameters were calculated using AM1 semiempirical molecular orbital methods and used as structure descriptors: average molecular polarizability (α), energy of the lowest unoccupied molecular orbit(ELUMO), energy of the highest occupied molecular orbit (EHOMO), the most positive charge on a hydrogen atom (q.), and the most negative atomic partial charge(q.) in the solute molecule. Then standard independent variables in TLSER equation was extracted and two series of quantitative equations between these quantum parameters and aqueous solubility and n-octanol/water partition coefficient were obtained by stepwise multiple linear regression (MLR) method. The developed equations have both quite high accuracy and explicit meanings. And the cross-validation test illustrated the good predictive power and stability of the established models. The results showed that TLSER could be used as a promising approach in the estimation of partition and solubility properties of macromolecular chemicals, such as persistent organic pollutants. [ABSTRACT FROM AUTHOR]

Platycodon grandiflorum cell suspension cultures were employed to biotransform the taxane diterpenoids 2α,5α, 10β,14β-tetraacetoxy-4(20),11-taxadiene (1) and 9α-hydroxy-2α,5α,10β,14β-tetraacetoxy-4(20),11-taxadiene (2). One product, 10b-hydroxy-2α,5α,14β-triacetoxy-4(20),11-taxadiene (3) was obtained from 1 and two products, 9α,10β-dihydroxy-2α,5α,14β-triacetoxy-4(20),11-taxadiene (4) and 10β-hydroxy-2α,5α,9α,14β-tetraacetoxy-4( 20),11-taxadiene (5) were obtained from 2 incubated with Platycodon cultured cells respectively, among which 5 is characterized as a new taxoid compound. The effects of the addition stage for 1 and 2 on the biotransformation were investigated and the results revealed that: (1) the optimal addition stage for 1 was in the early logarithmic phase (6th day) of the cell growth period, in which 78% of 1 was converted and the yield for 3 reached 75%; (2) the optimal addition stage for 2 was on the mid-logarithmic phase (12th day) of the cell growth period, in which 25.3% of 2 was converted and the yields for 4 and 5 reached 18.9 and 14.5%, respectively. [ABSTRACT FROM AUTHOR]

To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR) Ca2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits were injected with DOX, 8 rabbits with DOX and Tau, and 9 rabbits with normal saline. Cardiac function, concentration of calcium in cardiomycocytes (Myo [Ca2+] i ), activity of SR Ca2+-ATPase (SERCA2a), level of SERCA2a mRNA and Ca2+ released channels (RYR2) mRNA were detected. The left ventricle tissues were observed by electron microscopy. The results showed that cardiac index, left ventricular systolic pressure, activity of SR Ca2+-ATPase and level of SERCA2a mRNA decreased, while Myo[Ca2+] i increased in DOX-treated rabbits. DOX could not affect the level of RYR2 mRNA. Tau intervention could alleviate the increase of left ventricular diastolic pressure, Myo[Ca2+] i and the decrease of SERCA2a mRNA induced by doxorubicin. The results suggested that downregulation of SERCA2a gene expression was an important mechanism of DOX-induced cardiomyopathy and that Tau could partially improve the heart function by reducing calcium overload and alleviating downregulation of SERCA2a mRNA. [ABSTRACT FROM AUTHOR]