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In this study, a semi-empirical model was proposed to calculate the penetration depth and cavity diameters generated by shaped charge jet into high and ultra-high strength concrete (H&UHSC) targets. A recently proposed axial penetration equation and the two-step mechanism of cavity growth were employed to determine the analysis. The predictions were validated with reference to the experiments conducted using a kind of H&UHSC named reactive powder concrete (RPC). Furthermore, the influences of the RPC compressive strength and the jet velocity on the penetration were analyzed. The results showed that the RPC targets had good protection efficiency for both penetration depth and cavity diameters as the compressive strength approaches approximately 250∼280MPa. Moreover, the radial cavity growth efficiency increased linearly with the increase of the jet velocity, while the axial penetration efficiency increased rapidly when the jet velocity was 1.0∼4.0km/s and reached the maximum at 4.0∼7.0km/s and tended to be stable as the jet velocity increased to greater than about 7.0km/s.

In this work, an optical waveguide in the chalcogenide glass (80GeS2–15Ga2S3–5Sb2S3) is fabricated for the first time and its optical properties are investigated. A one-dimensional chalcogenide waveguide structure has been formed by 550 keV He+ ion implantation with a dose of 4 × 1016 ions/cm2 at room temperature. The effective refractive indices of the guided modes at the wavelength of 632.8 nm were measured with the aid of the Model 2010 Prism Coupler system. The refractive index profile, a critical factor in the analysis of waveguide structure, was reconstructed by the reflectivity calculation method. It was found that a positive change of refractive index occurred in the waveguide region, and an optical barrier with decreased refractive index was built at the end of the ion trajectory, i.e., producing a type of “well + barrier” structure. The SRIM 2013 program was utilized to display the profile of the energy loss versus the penetrated depth when the incident ion beam implanted. The near-field intensity distribution for the fundamental mode along the TE polarization was simulated through the finite-difference beam propagation method. From our experiments, these data provide a great deal of useful information about the manufacture of the chalcogenide waveguide structure.

Experiments on shaped charge penetration into high and ultrahigh strength steel-fiber reactive powder concrete (RPC) targets were performed in this paper. Results show that the variation of penetration depth and crater diameter with concrete strength is different from that of shaped charge penetration into normal strength concrete (NSC). The crater diameter of RPC is smaller than that of NSC penetrated by the shaped charge. The jet particles are strongly disturbed and hardly reach the crater bottom because they pass through the narrow channel formed by jet penetration into the RPC. The effects of radial drift velocity and gap effects of jet particles for a shaped charge penetration into RPC target are discussed. Moreover, a theoretical model is presented to describe the penetration of shaped charge into RPC target. As the concrete strength increases, the penetration resistance increases and the entrance crater diameter decreases. Given the drift velocity and narrow crater channel, the low-velocity jet particles can hardly reach the crater bottom to increase the penetration depth. Moreover, the narrow channel has a stronger interference to the jet particles with increasing concrete strength; hence, the gap effects must be considered. The drift velocity and gap effects, which are the same as penetration resistance, also have significant effects during the process of shaped charge penetration into ultrahigh-strength concrete. The crater profiles are calculated through a theoretical model, and the results are in good agreement with the experiments.

The antiknock additive methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese(Mn) compound. Mn neurotoxicity caused by occupational Mn exposure (mostly inorganic MnCl

Ion implantation has played a unique role in the fabrication of optical waveguide devices. Tb3+-doped aluminum borosilicate (TDAB) glass has been considered as an important magneto-optical material. In this work, near-infrared waveguides have been manufactured by the (5.5 + 6.0) MeV C3+ ion implantation with doses of (4.0 + 8.0) × 1013 ions·cm-2 in the TDAB glass. The modes propagated in the TDAB glass waveguide were recorded by a prism-coupling system. The finite-difference beam propagation method (FD-BPM) was carried out to simulate the guiding characteristics of the TDAB glass waveguide. The TDAB glass waveguide allows the light propagation with a single-mode at 1.539 μm and can serve as a potential candidate for future waveguide isolators.

BACKGROUND: Anemia is prevalent in patients undergoing transcatheter aortic valve replacement (TAVR) and has been linked to impaired outcomes after the procedure. Few studies have evaluated the impact of anemia and new ischemic lesions post TAVR. METHODS: We prospectively enrolled 158 patients who received TAVR in our center. Anemia was defined according to the World Health Organization criteria as hemoglobin

The depth of penetration (DOP) for concrete targets generated by a jet is required to achieve a certain value, under the premise of which the crater diameter must be sufficiently large in the present design of a shaped charge. A large cavity generated by the precursor shaped charge of a tandem warhead is conducive to the penetration of the follow-through projectile. Given the rapidly developing and increasingly extensive application of high and ultra-high strength concrete (H&UHSC), which has excellent resistance to penetration, impact and blasting, shaped charge jet penetration into the targets was investigated in this study. The chase between the incoming elastic wave, plastic wave and the jet/target interface as the shaped charge jet moves into H&UHSC targets were discussed. The response regions in the target were analyzed. Four penetration stages were proposed, while the corresponding modified Bernoulli equations were established. The two-stage mechanism of cavity growth was used to describe the penetration modes. Furthermore, the DOP experiments for two different structures of shaped charge penetration into H&UHSC targets with four strength grades were conducted. The predictions of depths and hole profiles from the present model correlate with the experimental data reasonably well. Results indicate that the DOP decreases exponentially as the compressive strength of H&UHSC increases at the beginning, and then the rate of the decreasing tendency slows down gradually and approximates the limit when the compressive strength approaches 200 MPa. Moreover, the cavity diameters resulted from the jet into the H&UHSC targets exhibit insensitivity to the increasing strength grade. The jet with diverse velocity and diameter structure may experience different penetration stages as it penetrates various H&UHSC targets, which affects the penetration result.

The carbon ion implantation with energy of 4.0 MeV and a dose of 4.0×1014 ions/cm2 is employed for fabricating the optical waveguide in fluoride lead silicate glasses. The optical modes as well as the effective refractive indices are measured by the prism coupling method. The refractive index distribution in the fluoride lead silicate glass waveguide is simulated by the reflectivity calculation method (RCM). The light intensity profile and the energy losses are calculated by the finite-difference beam propagation method (FD-BPM) and the program of stopping and range of ions in matter (SRIM), respectively. The propagation properties indicate that the C2+ ion-implanted fluoride lead silicate glass waveguide is a candidate for fabricating optical devices.

We report on the preparation and properties of an optical planar waveguide structure operating at 1539 nm in the Yb3+-doped silicate glass. The waveguide was formed by using (470 + 500) keV proton implantation at fluences of (1.0 + 2.0) × 1016 ions/cm2. The waveguiding characteristics including the guided-mode spectrum and the near-field image were investigated by the m-line technique and the finite-difference beam propagation method. The energy distribution for implanted protons and the refractive index profile for the proton-implanted waveguide were simulated by the stopping and range of ions in matter and the reflectivity calculation method. The proton-implanted Yb3+-doped silicate glass waveguide is a candidate for optoelectronic elements in the near-infrared region. Keywords: Waveguide, Yb3+-doped silicate glasses, Ion implantation

The influence of the soil/concrete interface of a shaped charge penetrator in a soil–concrete double-layered target is discussed. The propagation and attenuation of compaction wave generated by the shaped charge penetrates the target. The reflection and transmission when the compaction wave reaches the interface for a double-layered target are analyzed. Moreover, a theoretical model is presented to describe the penetration of shaped charge into soil–concrete double-layered target. The reflected and transmitted waves, which remarkably reduce penetration velocity when the shaped charge penetrator passes through the soil/concrete interface, play an important role in penetration depth. The penetrations of the shaped charge penetrator into the concrete and soil–concrete double-layered targets are compared experimentally. The penetration depth in the soil–concrete double-layered target is less than in the concrete target penetrated by the shaped charge penetrator despite the smaller density and strength of the soil than that of concrete. The predicted penetration depth via theoretical model is in good agreement with experimental results.

It is hard for general shaped charge jet to enlarge a large crater hole, when it penetrate the concrete target. The non-cohesion jet may do it. In this paper, the character of the noncohesion jet formed by shaped charges which liner were two phase alloy (titanium alloy) were studied by X-ray experiment and the penetration ability was firmed through DOP experiments. The results show that compare with OFHC jet, the non-cohesion formed by the TC21 liner and NiTi liner can enlarge the crater hole and have certain penetration ability.

Reactive powder concrete (RPC), a composite that is cured to have ultra-high compressive strength, high durability and high toughness, has been developed in recent years. In this study, the penetration model as shaped charge jet (SCJ) into RPC targets was investigated. The penetration resistance and the anti-impact performance of RPC targets were analyzed. Restlts showed that depth of penetration (DOP) experiments had a good agreement with the calculations. The DOPs of RPC targets created by shaped charge jets are more sensitive to the compressive strength than cavity diameters. In addition, the effect of the jet velocity on penetration resistance was significantly greater than concrete strength do. The higher the jet velocity was, the smaller the compressive strength affected the penetration resistance. With the increase of the RPC compressive strength, the increase of the penetration resistance showed a gradual downtrend. The incrementary ratio of the penetration resistance with the increasing RPC compressive strength was smaller when the jet velocity range was 5.0~10.0km/s compared with that when 1.0~5.0km/s. Moreover, the impact crater depth is affected more by compressive strength of concrete than that by steel fiber volume fraction. The area of the impact crater is no longer reduced as the volume fraction of steel fiber is more than 2% (compressive strength is more than 180MPa), while the depth and volume of impact crater are still decreasing.

In this study, the performance of titanium alloys (TC21, TC1), nickel-titanium (Ni-Ti) alloy, and zirconium-niobium (Zr-Nb) alloy lined shaped charge impact and penetration into concrete targets are investigated experimentally. Shaped charge jet radiographs reveal that the resulting jets of titanium alloys and Ni-Ti alloy exhibit particulate, radially dispersed behaviors, whereas that of the Zr-Nb alloy is coherent. Cavity diameters, penetration depths and parameters of the impact craters generated by the jets were analyzed using the depth of penetration (DOP) experiment method. Data indicate that the particulated jet causes more extensive damage to the surface of the concrete targets compared to the coherent jet. The penetration depth decreases to some degree, but the cavity diameter increases significantly. Penetration efficiency varies with degree of dispersion of the particulated jet and, as such, is also sensitive to stand-off distance.

The traditional dynamic cavity expansion theory generally deals with the problem of penetrator penetration into targets at lower velocity, which is considered that the materials near the penetrator/target interface are in the plastic state. For shaped charge jets penetration, the concrete materials in a certain distance away from the jet/target interface are in the fluid state. Thus, the radial stress at the cavity surface derived from the dynamic cavity expansion theory cannot be directly applied as the target resistance. The current paper aims to establish a theoretical model for shaped charge jets penetration into concrete targets based on the cavity expansion idea, assuming that the cavity expansion stress is the stress at the flow/fully dense interface. Firstly, the hydrostatic pressure-volume strain relationship described by the HJC concrete constitutive model was analyzed; result indicated that four response regions were produced when concrete subjected to load: the elastic region, the cracked region, the plastic-like (the “plastic” behavior of concrete is named as “plastic-like” since the behavior has nothing to do with the dislocation movement of metals that reflects the plastic behavior) transitional region and the fully dense region. The HJC yield surface equation was then modified by discussing the elastic-cracked-transitional-fully dense response in front of the flow/fully dense interface. With the changing particle velocity at the flow/fully dense interface, it showed that another three response modes were produced in front of the flow/fully dense interface, i.e., the elastic-transitional-fully dense response, the elastic-fully dense response, and the fully dense response. The applications of the equations of state in different response modes were analyzed. Secondly, the calculation model of the radial stress at the flow/fully dense interface was proposed based on the modified HJC model. Thirdly, the shaped charge jets penetration theories were analyzed. In the end, the depth of penetration (DOP) experiments for three different shaped charges into C200 reactive powder concrete (RPC) targets were carried out to verify the theoretical model. Results showed that the cavity diameters and penetration depths predicted by the elastic-cracked-transitional-fully dense response, the elastic-transitional-fully dense response and the elastic-fully dense response exhibited good agreement with the experimental data, whereas that by the fully dense response existed relatively large errors comparing with the other three response modes.

The investigation on the terbium gallium garnet (TGG) crystal waveguides in the visible and near-infrared bands is significant for potential applications in science and technology. In this work, we report on a TGG planar waveguide based on the proton irradiation with an energy of 400 keV and a dose of [Formula: see text] ions/cm2. The annealing treatments are adopted to improve optical performances of the waveguide on the conditions of 260[Formula: see text]C and 410[Formula: see text]C severally for 1 h. The dark-mode spectra and the refractive index distributions of the TGG waveguide are obtained before and after the thermal treatments. There is a strange phenomenon that nine modes are observed on the m-line curve after the annealing treatment at 410[Formula: see text]C. The theoretical and experimental results demonstrate that the fabricated waveguide annealed at the temperature of 410[Formula: see text]C can propagate more guided modes and have better capacity to confine light.

We report on the fabrication of a ridge waveguide in the Tb3 + -doped aluminum borosilicate glass by combining the 550-keV proton implantation and the precise diamond blade dicing with a rotating speed of 20,000 rpm. The relative atom displacement of the original structure induced by the proton implantation is simulated by Stopping and Range of Ions in Matter 2013 in the Tb3 + -doped aluminum borosilicate glass. The morphology of the ridge waveguide is acquired by scanning electron microscopy. The near-field intensity distribution of the waveguide is recorded by the end-face coupling system, which indicates that the light can be well confined in the ridge waveguide region.

We report on the preparation and characterization of the planar and ridge waveguides in TGG crystals. The planar waveguide was formed by the 6.0-MeV Si-ion implantation with a dose of 2.0 × 1015 ions/cm2 and the precise diamond blade dicing technique was applied to manufacture the surface of the planar waveguide to construct the ridge structure. The images of planar and ridge cross-sections were photographed by a metallographic microscope. The SRIM 2013 was utilized to achieve the energy loss profiles of electrons and nuclei. The dark-mode spectra and the guiding properties were separately measured by the prism coupling and end-face coupling methods. The simulation processing on the refractive index profile and the near-field mode distribution were operated by the RCM and the BPM software, respectively. In consideration of the high-quality optical propagation performances, the TGG planar and ridge waveguides can serve as superior candidates in the magneto-optical devices.

Four new triterpenoid saponins, Catunaroside I [3-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-arjunic acid 28-O-β-D-glucopyranoside] (1), Catunaroside J [3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyl-arjunic acid 28-O-β-D-glucopyranoside] (2), Catunaroside K [3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyl-tormentic acid] (3), and Catunaroside L [3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyl-pomolic acid] (4), and two known triterpenoid saponin Arjunetoside (5) and Randiasaponin VII (6), were isolated from the stem bark of Catunaregam spinosa. Their structures were elucidated on the basis of their spectral data and chemical evidence.

A series of [1,3]dioxolo[4,5-f]isoindolone derivatives were designed, synthesized and evaluated as inhibitors of acetylcholinesterases (AChE). Furthermore, their effects on memory impairment of mice induced by scopolamine were investigated with step-through test. The results suggested that most of the target compounds exhibited potential inhibition on AChE with IC50 values at micromolar range. Compounds I1 (IC50 value of 0.086 μmol · L(-1)) and I2 (IC50 value of 0.080 μmol · L(-1)) showed the strongest AChE inhibitory activity, which are equipotent to donepezil (IC50 value of 0.094 μmol · L(-1)). Moreover, compounds I1-I4 could improve the memory impairment induced by scopolamine in mice.

Four new triterpenoid saponins, Catunaroside I [3-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-arjunic acid 28-O-β-D-glucopyranoside] (1), Catunaroside J [3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyl-arjunic acid 28-O-β-D-glucopyranoside] (2), Catunaroside K [3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyl-tormentic acid] (3), and Catunaroside L [3-O-β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranosyl-pomolic acid] (4), and two known triterpenoid saponin Arjunetoside (5) and Randiasaponin VII (6), were isolated from the stem bark of Catunaregam spinosa. Their structures were elucidated on the basis of their spectral data and chemical evidence.

Aim: To investigate the role of intercellular potassium in tachyplesin-induced HL-60 cells apoptosis. Methods: The concentration of intercellular potassium, cell volume and mitochondrial membrane potential were examined by flow cytometry. Results: The concentration of intercellular potassium reduced in a time-dependent manner in tachyplesin-treated HL-60 cells. In addition, the loss of mitochondrial membrane potential was tightly coupled with the shrinkage of cell volume. Different caspase inhibitors protected against DNA degradation but did not prevent the loss of HL-60 cell viability induced by tachyplesin. Ba 2+ , which was a kind of blocker of volume-regulatory K + channels, increased the viability of tachyplesin-treated HL-60 cells and maintained mitochondrial membrane potential and cell volume. Conclusion: Efflux of K + was an important reason for apoptosis in tachyplesin-treated HL-60 cells. Efflux of K + affected the viability of tachyplesin-treated HL-60 cells independent of the process of caspase activation.

A series of novel 4-substituted-3-nitrobenzamide derivatives were designed and synthesized. The structures of the target compounds were confirmed with 1H NMR, 13C NMR, MS and element analysis. Anti-tumor activities against HCT-116, MDA-MB435 and HL-60 cell lines in vitro were evaluated by SRB assay. The results indicated most of the target compounds exhibited potent anti-tumor activity. Compound 4a showed the most potent inhibitory activities against three cancer cell lines with the GI50 values of 1.904-2.111 micromol x L(-1). Compounds 4g, 41-4n exhibited more potent inhibitory activities against MDA-MB435 and HL-60 cell lines with the GI50 values of 1.008-3.586 micromol x L(-1) and 1.993-3.778 micromol x L(-1), respectively. The structure-activity relationship of these compounds is discussed preliminarily.

Objective To study the mechanisms of the antitumor and immunoregulation functions of polyporus polysaccharide (PPS). Methods The production of nitric oxide (NO), the activity and mRNA expression of inducible nitric oxide synthase (iNOS) in peritoneal macrophages of mice administered with different dose of PPS were observed by Griess reaction, fluorimetry assay and RT-PCR, respectively. Results PPS could elevate the iNOS activity with dose-dependence and stimulate the iNOS mRNA expression of peritoneal macrophages in mice. Conclusion The regulation of PPS on the production of NO in peritoneal macrophages of mice may occur at transcriptional level of iNOS. This indicates that the mechanism of PPS's antitumor and immunoregulation functions may be related to increasing NO output of macrophages through stimulating iNOS's denovo synthesis.

Development of successful formulations for poorly water-soluble drugs remains a longstanding critical and challenging issue in cancer therapy. The stearic acid-g-chitosan oligosaccharide (CSO-SA) micelles have been presented as potential candidates for intracellular antitumour agent delivery carrier. Herein, podophyllotoxin (PPT) loaded CSO-SA micelles (CSO-SA/PPT) were prepared by a dialysis method. The drug encapsulation efficiency could reach a higher level, the micellar size and the zeta potential increased with increasing charged amounts of drug. The cumulative release percentage of PPT drug from micelles enhanced with decreasing PPT content in the micelles. The cytotoxicities of CSO-SA/PPT micelles against human breast carcinoma (MCF-7) cells, human lung cancer cells (A549) and human hepatoma cell line (Bel-7402) were higher than that of free PPT formulation. The higher cytotoxicities were due to the faster PPT transport into tumour cells mediated by CSO-SA micelles. Overall, CSO-SA micelles might be a promising carrier for PPT delivery in cancer therapy.

Multidisciplinary Design Optimization (MDO) is an effective and prospective solution to complex engineering systems. In MDO methodology, MDO algorithm is the most important research area. Four decomposition algorithms have been proposed for MDO. They are Concurrent subspace optimization (CSSO), Collaborative optimization (CO), Bi-level integrated system synthesis (BLISS) and Analytical target cascading (ATC). On the basis of specific requirements for comparison, a mathematical example is chose and the performances of MDO decomposition algorithms are evaluated and compared, which take into consideration optimization efficiency and formulation structure characteristics.

Research on the drag-reducing structure of the haploid interval riblets surface is carried out with the numerical simulation, and in view of its flow field features, this paper appropriately deals with the computing domain, grids and flow parameters during the numerical calculation. By the adoption of iSIGHT software, structure parameters generated program of riblets surface, hydrodynamic numerical simulation software GAMBIT and FLUENT is integrated. With optimized design technology and the numerical simulation technology, the optimization design of the bottom angle on the riblets surface is made by adopting the two-stage combining optimization method which includes overall search based on adaptive simulated annealing algorithm and partial optimal search of sequential quadratic programming. The results show that after the optimization design, the relative amount of drag reduction of the riblets surface reaches 3.506 %. Compared with the initial value, the relative amount of drag reduction increases and the drag-reducing effect is remarkable. This provides a new direction for the research on drag reduction of riblets surface.

To study the relation between cell cycle change and apoptosis of serum-deprived PC12 cell, which are induced by beta-amyloid peptide-25-35 (alpha beta(25-35)).PC12 cells were synchronized by cultured in deprivation of serum for 24 h and treated with different concentration of alpha beta(25-35) (0-45 micromol/L) for another 24 h,and the cell survival rate was evaluated by MTT assay. The cell apoptosis was analyzed by Hoechst fluorescence staining and DNA agarose gel electrophoresis. The relation between cell cycle redistribution and apoptosis was analyzed by flow cytometry (FCM).alpha beta(25-35) decreased the survival rate of PC12 cells in dose-dependent manner. The typical apoptotic cells were showed by fluorescence staining when treated with 25 micromol/L alpha beta(25-35) for 24 h;the obvious DNA-Ladder was showed by DNA agarose electrophoresis. About 90% PC12 cells were found to arrest on G0/G1 by FCM being deprived serum. Treated with 25 micromol/L alpha beta(25-35) for 8, 16, 24 h, the percent of S phase cells was raised remarkably (P0.01) at 8 h, but the percent of S phase cells was declined gradually after treated for 16 h. Meanwhile the apoptotic rate was detected being increased obviously between 16 h and 24 h (P0.01), the obvious hypodiploid peak could be observed ahead of G0/G1 phase(Ap).alpha beta(25-35) decreases the survival rate of synchronized PC12 cell and induces the synchronized PC12 cells attempting to reenter cell cycle,which appear the apoptotic peak subsequently. This indicates that the cell apoptosis may be related to the abnormal cell cycle distribution induced by alpha beta(25-35), which means there may be a close relationship between cell cycle and apoptosis.