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Bismuth thiophosphate, BiPS4, is a promising nontoxic, high-density ternary chalcogenide semiconductor. Polycrystalline BiPS4was synthesized from the stoichiometric melt of Bi, P, and S. Phosphorus was purified via an in-situ sublimation method. Single crystals of BiPS4were grown using a modified vertical Bridgman method with a thermal gradient of 18 °C/cm. The material exhibits an electrical resistivity of 2 × 109Ω·cm. The Knoop hardness of the single crystals is 128 ± 0.8 kg mm–2. A blocking contact behavior was observed with asymmetric contacts of Ga/BiPS4/Ag. A clear photocurrent response was observed from a BiPS4crystal under an electric field as low as 1.14 V mm–1. Using a tungsten X-ray source, an X-ray sensitivity of 52 μ Gy–1cm–2was measured under an electric field of 80 V mm–1. When a single-crystal BiPS4radiation detector device was used in a pulse-height radiation detection system, a clear charge collection response was observed under a 241Am α-particle radiation source.

Tomographic Gamma Scanning (TGS) is a nondestructive analysis technique for accurately measuring the content of radioactive material in sealed containers. It has important applications in the fields of nuclear safety assurance and the measurement and analysis of radioactive waste drums. As the key of TGS technique, the quality of the emission image reconstruction algorithm will directly affect the accuracy of measurement results. In this paper, a computer simulation platform for TGS technique is established. The application of four emission image reconstruction algorithms in TGS technique is systematically studied by using 6 · 6 · 6 sample voxel model. Three representative sample media and radioactive source distribution models are established and the applicability of the four reconstruction algorithms is analyzed and evaluated in the presence and absence of detector noise interference. Computer simulation and experimental results show that ML-EM algorithm is the most applicable in the process of TGS image reconstruction.

The investigations of bismuth halide chemistry in DMSO/MeOH solutions led to the discovery of a new solvent-stabilized compound with a chemical formula of Cs3BiBr6·3DMSO. In addition, a new phase of Cs3BiBr6was generated as a result of a crystal-to-crystal transition driven by the change in the solvent composition. The solvent stabilized Cs3BiBr6·3DMSO adopts an orthorhombic P212121type crystal structure with unit cell dimension of a= 13.6160(6) Å, b= 14.4359(8) Å, and c= 14.6487(7) Å. Bulk single crystals of Cs3BiBr6·3DMSO with average size of 4.5 × 3.5 × 3.5 mm3were grown by the antisolvent crystal growth method. With the change of the solvent composition from 2:1 DMSO: MeOH to 1:1 DMSO: MeOH, the single crystals of Cs3BiBr6·3DMSO underwent a crystal-to-crystal transition yielding another structurally distinct Cs3BiBr6phase, with a tetragonal P42/mtype structure and unit cell dimensions of a= 9.8394(5) Å, b= 9.8394(5) Å, and c= 8.0950(6) Å. Both compounds exhibit isolated BiBr6octahedral resembling the structures of the zero-dimensional (0D) perovskites.

Using first-principles calculations, we investigate the adsorption behavior of hydrogen on the planar hexagonal ZnO sheet. Our calculations find that the planar ZnO monolayer preferably adsorbs hydrogen molecules, where a hydrogen molecule attaches to one oxygen atom with binding energy of ∼0.13 eV. This implies that the interaction between a hydrogen molecule and the ZnO sheet is stronger than that between a hydrogen molecule and graphene. We predict that each oxygen atom in a ZnO sheet can adsorb two hydrogen molecules on opposite sides of the sheet, and thus the gravimetric density for hydrogen storage on ZnO sheet is evaluated to be about 4.7 wt % at zero temperature. Furthermore, our calculations show that the gravimetric density for hydrogen storage on ZnO sheet reaches 1.5–2.1 wt % at 298 K and 5 MPa. This suggests that, despite their weight, ZnO sheets may have potential applications in hydrogen storage.

Dendrimers, a class of synthetic macromolecules which are notable for their well-defined ramified structures and unique multivalent cooperativity, hold great promise for developing various functional materials. Among all the reported dendrimers, poly(amidoamine) (PAMAM) dendrimers are the most extensively studied by virtue of their readily availability via robust synthesis as well as their dendritic structure and peptide/protein mimic features. Since the seminal report by Tomalia et al., various strategies have been made available for PAMAM dendrimers, including divergent and/or convergent synthesis alongside click chemistry. Nevertheless, preparation of high-generation and defect-free PAMAM dendrimers on a large scale remains challenging. To overcome the limitations, an alternative strategy based on self-assembling approach has emerged for dendrimer synthesis, where small dendritic components form large non-covalent supramolecular structures that mimic high-generation covalent dendrimers. This approach is easy to implement in practice and requires much less synthetic effort. Here, we present a brief overview of the different approaches established for PAMAM dendrimer synthesis. We start with a general introduction to dendrimers and the common strategies for dendrimer synthesis, and then we illustrate the specific approaches for PAMAM dendrimer synthesis and highlight the related advantages and limitations using representative examples. Although various strategies have been established for PAMAM dendrimer synthesis, innovative concepts and approaches are still in high demand for reliably preparing defect-free and high-generation dendrimers in large quantity.

ABSTRACTThe creep deformation behaviour of thermo-mechanically treated AlxCrMnFeCoNi high-entropy alloys was investigated in the high-temperature range of 600–700°C. Compared with the Al-free CrMnFeCoNi alloy, the AlxCrMnFeCoNi alloys showed higher creep resistance under the same creep conditions due to strengthening contribution from elemental Al. The Al0.4CrMnFeCoNi alloy exhibited a stress-dependent transition from the low-stress region to high-stress region. The Al0.6CrMnFeCoNi alloy showed decreased creep resistance compared to the Al0.4CrMnFeCoNi alloy, which was ascribed to the higher activation volume and stacking-fault energy in the former alloy. Specifically, the intragranular formation of Cr-rich σ precipitation was widely found in the matrix grain among testing conditions, indicating a striking atomic diffusion process due to the limited entropic stabilisation in Al-containing CrMnFeCoNi alloys.

In the rail gun system, the current fluctuation occurs which causes the changes of the electromagnetic stiffness and forms disturbance to the dynamics system. It may lead to disturbances of the projectile trajectory. This is an electromechanical-coupled parametric vibration problem and should be investigated. Rails in electromagnetic railgun are assumed to be elastic foundation beams. The current flowing through the rail causes an electromagnetic repulsive force between the two rails. The fluctuation of rail current causes mechanical vibration and stiffness change of the rails. The wave current is assumed to vary in the cosine function. Considering the current fluctuation in the railgun system, an electromechanical-coupled parametric vibration equation is proposed. Using Poincare method, the coupled parameter vibration equation is resolved. As the dynamic current amplitude, the static current, and distance of the armature to the entrance of the gun increase, the unstable region of the railgun system vibrations increases. As the distance between the two rails, the rail thickness and the rail width, and the stiffness of the elastic foundation increases, the unstable region of the railgun system vibrations decreases. In this paper, the unstable regions of the railgun system are determined and their changes as the function of the system parameters are analyzed. Results can be used to increase the stability of electromagnetic railgun.

To obtain reliable 3D stacking, a void-free bonding interface should be obtained during wafer-to-wafer direct bonding. Historically, SiO2is the most studied dielectric layer for direct bonding applications, and it is reported to form voids at the interface. Recently, SiCN has raised as a new candidate for bonding layer. Further understanding of the mechanism behind void formation at the interface would allow to avoid bonding voids on different dielectrics. In this study, the void formation at the bonding interface was studied for a wafer pair of SiO2and SiCN deposited by plasma enhanced chemical vapor deposition (PECVD). The presence of voids for SiO2was confirmed after the post-bond anneal (PBA) at 350 °C by Scanning Acoustic Microscopy. Alternatively, SiCN deposited by PECVD has demonstrated a void-free interface after post bond annealing. To better understand the mechanism of void formation at the SiO2bonding interface, we used Positron Annihilation Spectroscopy (PAS) to inspect the atomic-level open spaces and Electron Spin Resonance (ESR) to evaluate the dangling bond formation by N2plasma activation. By correlating these results with previous results, a model for void formation mechanism at the SiO2and the absence of for SiCN bonding interface is proposed.

Dendrimers, by virtue of their unique well-defined dendritic structure and multivalent cooperativity, hold great promise for a wide variety of applications, ranging from healthcare to energy production and environmental sustainability. However, dendrimer synthesis suffers from two inherent problems which greatly handicap their development and limit their application: the formation of structural defects caused by incomplete or side reactions, and difficulties associated with purification. Solid-phase synthesis may overcome both these problems, firstly by enabling complete chemical reactions through the use of a large excess of reagents, secondly by facilitating purification through simple washing and filtering steps. The end result is the speeded up reactions producing the desired product in high yield, with simultaneous suppression of by-products. In this review, we present the challenges and current state of research in solid-phase dendrimer synthesis, and provide our perspectives on its future development. We start with a short introduction to solid-phase synthesis and specific considerations for dendrimer construction. We then present exemplary studies to highlight the potential of, and challenges faced by, solid-phase dendrimer synthesis. Finally, we describe efforts to deliver more effective and reliable methods that will transform the synthesis of dendrimers and permit exploitation of their full potential.

Metallic bipolar plates (BPPs) are key components of the proton exchange membrane fuel cell (PEMFC). To lower the fabrication cost of metallic BPPs, precoated BPPs have attracted much attention due to the high efficiency of precoating-stamping process. However, precoatings on metallic substrate tend to crack during the forming process, leading to deterioration or even complete loss of corrosion resistance. Therefore, to avoid micro cracks of formed precoated BPPs, development of coatings with high ductility is necessary. In this study, Niobium coatings with different thicknesses on SS316L substrate are prepared with magnetron sputtering process, and uniaxial tensile tests are then conducted for the precoated specimens to evaluate their ductility. The microstructure and fracture behaviour of the Niobium precoatings are characterized by XRD, SEM, TEM, laser confocal microscope analysis. It is found that with the increase of coating thickness, the number of micro cracks at the same strain decreases significantly, and the strain for the first crack to appear also increases. Furthermore, a brittle-to-ductile transition of fracture mechanism is observed. The grain size of Niobium nanocrystalline coating increases with the thickness, which leads to the improvement of plasticity and failure strain. Therefore, the application of precoated metallic BPPs is further advanced.

Chemical unit cosubstitution is an effective strategy to regulate the luminescence properties of phosphors, and it has attracted huge attention in the last few years. Following the design principles of the match of effective ion radius, atomic valence equilibrium and stoichiometric substitution, the local structure of crystal can be well customized, which is beneficial to develop high-performance luminescent materials. In this work, Mg2+-Sn4+sites were cosubstituted by Zn2+-Ti4+ion pairs in Mg2SnO4: Cr3+, respectively, and the emission spectra was successfully serially tuned from broad-band to narrow-band along with a unique variation trend of blue shift first and then slightly red shift. The photoluminescence excitation (PLE), photoluminescence (PL) spectra, lifetime decay, Raman spectra and electron paramagnetic resonance (EPR) were used to analyze the mechanism of luminescence tuning. Based on the manipulation of local structure, the as-observed distinct luminescence tuning can be well understood by the crystal field theory, nephelauxetic effect and changed Cr3+capacity in this phosphor. Moreover, the adjusted narrow-band far-red emission spectra peak at 732 nm, matching the characteristic absorption of plant phytochrome PFR, has broad application prospects in the field of plant growth lighting. In addition, light-regulated dwarf potted tomato experiments were carried out to verify the application of far-red light in plant growth.

Glucokinase (GCK) is an important enzyme critical for glucose metabolism, and has been targeted as such in the pursuit of a cure for diabetes mellitus. We show that streptozotocin (STZ)-induced diabetic murine model exhibits low GCK expression with high blood glucose levels; moreover, aggravated glomerulonephritis is observed in the model when there is IL10 deficiency. Although T cells infiltrate into the liver and pancreas in STZ-induced diabetes mice, T helper 1 (Th1) and T helper 17 (Th17) cells decrease significantly with STZ addition in in vitro polarization. Using a mutant GCK gene (GCK 262) with a knocked out cytosine at position 2643 results in lower protein expression and more ubiquitination-led protein degradation compared with wild-type GCK (GCK 261). We further observed that hsa-mir-1302 can bind to 3′-untranslated region of mutant GCK, which can decrease GCK mRNA translation. Finally, delivery of mutant GCK by subcutaneous injection is more effective at decreasing blood glucose in the STZ-treated (STZ) murine diabetes model than insulin treatment alone. Similarly, mutant GCK consistently and moderately decreases blood glucose levels in GK rats over a period of 12 and 70 days without inducing hypoglycemia, whereas insulin is only effective over 12 h. These results suggest that mutant GCK may be a future cure for diabetes.

Study design:Experimental study.Objectives:To investigate the effect of pre-treatment with PMX53, a C5aR antagonist, on spinal cord ischemia-reperfusion injury (IRI) in rat.Setting:Department of Neurosurgery, Second Affiliated Hospital, Xi’an Jiaotong University School of Medicine, Xi’an, Shaanxi Province, China.Methods:IRI was induced in the lumbar spinal cord by applying a mini aneurysm clamp to the abdominal aorta for 60 min in adult Sprague–Dawley rats. PMX53 (1 mg kg−1) was administered through femoral vein injection 30 min before ischemia on the rats in the PMX53 group (n=18). The saline group (n=18) was given saline at the same volume through femoral vein injection. The neurologic outcome of the posterior limbs was assessed by the Basso-Beattie-Bresnahan (BBB) score at 1, 6, 12, 24 and 48 h after reperfusion. Histologic changes of the spinal cord were detected with hematoxylin–eosin (H–E) staining. Enzyme-linked immunosorbent assay (ELISA) was used to detect myeloperoxidase (MPO) activity in the spinal cord. Immunohistochemistry was used to investigate the quantity of activated astrocytes and microglia.Results:After pre-treatment with PMX53, neurologic function improved gradually after 6, 12, 24 and 48 h reperfusion. The BBB score of the PMX53 group increased significantly (P<0.05) compared with the saline group. H–E staining showed that pathologic damage in the PMX53 group was reduced. Moreover, administration of PMX53 significantly inhibited neutrophil infiltration in the spinal cord. Levels of MPO activity in the spinal cord were remarkably lower in the PMX53 group (P<0.05). There were also more activated microglia and astrocytes in the spinal cord of the PMX53 group than in the saline group (P<0.05).Conclusion:PMX53 delivered 30 min prior to ischemic injury protects the spinal cord from IRI, probably via the inhibition of neutrophil activity, increased activated microglia and astrocyte.

This study was to examine the effects of four fungal polysaccharides, namely exo-polysaccharide (EPS), water-extracted mycelia polysaccharide (WPS), sodium hydroxideextracted mycelia polysaccharide (SPS), and hydrochloric-extracted mycelia polysaccharide (APS) obtained from the endophytic fungus Bionectra pityrodesFat6, on the sprout growth and flavonoids production of Fagopyrum tataricum. Without obvious changes in the appearance of the sprouts, the exogenous polysaccharide elicitors notably stimulated the sprout growth and functional metabolites accumulation, and the stimulation effect was mainly depended on the polysaccharide species along with its treatment dose. With application of 150 mg/l of EPS, 150 mg/l of WPS and 200 mg/l of SPS, the total rutin and quercetin yield of buckwheat sprouts was effectively increased to 49.18 mg/(100 sprouts), 50.54 mg/(100 sprouts), and 52.27 mg/(100 sprouts), respectively. That was about 1.57- to 1.66-fold in comparison with the control culture of 31.40 mg/(100 sprouts). Moreover, the present study revealed the accumulation of bioactive flavonoids resulted from the stimulation of the phenylpropanoid pathway by fungal polysaccharide treatments. It could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts applied with specific fungal elicitors.

AbstractA hot isostatic pressing (HIP) route has been developed by the Institute of Plasma Physics of the Chinese Academy of Sciences in collaboration with the Advanced Technology & Materials Co., Ltd. for bonding W/Cu tiles to Ni-electroplated CuCrZr heat sinks. During high-heat-flux testing, in the initial stage, Cu/Ni interfacial debonding was observed. Careful analyses indicated that interfacial oxidation during encapsulation for HIP processing using tungsten inert gas (TIG) welding was the main cause of the limited fatigue lifetime. Copper oxides formed during the TIG encapsulation do not decompose during HIP at 600°C. As a result, weak bonding and even some microcracks were generated, and unfortunately these microcracks could not be detected by current industrial ultrasonic probes. An oxidation-free encapsulation technique, suitable for batch processing, has been developed to achieve a thermal fatigue lifetime of more than 1000 cycles at a heat load of 5 MW/m2for the components.

The genus Paedocypris is a newly described taxon of minifish species that are characterized by extensive chromosome evolution and one of the smallest known vertebrate nuclear genomes. Paedocypris features a tiny adult size, a short generation time, low fecundity and fragmented tropical habitats, which are factors that favor rapid speciation. Most recently, we have revealed that P. progenetica (Pp), the type species of the genus Paedocypris, has an unusual mtDNA bearing - within its D-loop - a tandem array of a 34-bp repeat sequence called the minifish repeat, which shows compromised replication efficiency in vitro. Here we report that Pp exhibits high genetic variation in mtDNA size. The efficiency of D-loop amplification was found to depend upon primers. Interestingly, Pp individuals of one and the same population differed drastically in mtDNA size resulting from varying copy numbers of the minifish repeat. We conclude that minifish has a high mutation rate and perhaps represents a rapidly evolving taxon of vertebrates.

An allotetraploid hybrid lineage derived from the distant hybridization of red crucian carp (Carassius auratus red var., , 2n =100) × common carp (Cyprinus carpio L., , 2n =100) was investigated for its mitochondrial and nuclear genome inheritance patterns. Based on liver transcriptomic data for this hybrid, red crucian carp, and common carp, we identified 94, 136, and 86 contigs corresponding to 41, 46, and 37 mitochondrial respiratory chain nuclear genes, respectively. Mitochondrial respiratory chain nuclear gene sequences from red crucian carp and common carp were both detected in the allotetraploid hybrid, indicating that both parental nuclear genomes were participated in the synthesis of mitochondrial respiratory protein complexes in the hybrid. For mitochondrial respiratory related genes, high sequence similarity (>90%) and a low nucleotide divergence rate (<0.2) between red crucian carp and common carp could be a critical factor allowing cooperation of the three genomes (red crucian carp mitochondrial genome, red crucian and common carp nuclear genomes) in the allotetraploid hybrid lineage. Interestingly, gene duplication events were identified in the allotetraploid hybrid, red crucian and common carp, as confirmed by analysis of orthologous gene trees for these fish. Our findings provide valuable information with which to study cooperation between the nuclear and mitochondrial genomes of other hybrids, and will provide basic genetic information of relevance to mitochondrial-related diseases in humans and animals.

Paedocypris is a newly described minifish genus endemic to Southeast Asia. Besides a tiny adult size of ~8 mm in length, minifish feature fragmentary habitats of acidic peat blackwater swamps, an unusual reproduction mode, truncated development and one of the smallest known genomes. A complete sequence is absent for the minifish mitochondrial DNA (mtDNA). Here we report the complete mtDNA sequence and its unusual feature in the minifish P. progenetica (Pp). We show that the Pp mtDNA is a circular molecule of 17,382 bp in length and has the same number of similarly oriented genes as in other vertebrates. Specifically, it comprises 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 D-loop. Surprisingly, the D-loop is elusive for amplification by standard PCR conditions. The D-loop possesses a 28-bp dinucleotide TA repeat and more intriguingly, up to 25 copies of a 34-bp tandem repeat sequence. These tandem repeats predict the formation of paired regions. Hence, besides a generally conserved mtDNA with other vertebrates, the Pp mtDNA features an unusual D-loop and compromised DNA replication in vitro.

The purpose of this study was to investigate the effects of endophytic fungi from tartary buckwheat on the host sprout growth and functional metabolite production. Without obvious changes in the appearance of the sprouts, the exogenous fungal mycelia elicitors notably stimulated the sprout growth and rutin accumulation, and the stimulation effect was mainly depended on the mycelia elicitor species along with its treatment dose. Three endophytic fungi Fat6 (Bionectria pityrodes), Fat9 (Fusarium oxysporum)and Fat15 (Alternariasp.) were screened to be the most effective candidates for promoting F. tataricumsprout growth and rutin production. With application of polysaccharide (PS, 150 mg/l) of endophyte Fat6, PS (200 mg/l) of endophyte Fat9, and PS (150 mg/l) of endophyte Fat15, the rutin yield was effectively increased to 47.89 mg/(100 sprouts), 45.85 mg/(100 sprouts) and 46.83 mg/(100 sprouts), respectively. That was about 1.5- to 1.6-fold compared to the control culture of 29.37 mg/(100 sprouts). Furthermore, the present study revealed that the biosynthesis of the functional flavonoid resulted from the stimulation of the phenylpropanoid pathway by mycelia polysaccharide treatments. Application of specific fungal elicitors could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts.

Pancreatic neuroendocrine tumors (PNETs) are rare but are well understood to cover a broad spectrum of clinical presentation, tumor biology and prognosis. More than 60 of PNETs are diagnosed at advanced disease stage and are ineligible for surgical resection. Prior to 2011, streptozocin was the only approved agent for unresectable advanced PNETs. In recent years, breakthroughs in signal pathway research have led to the identification of new therapeutic targets and agents directed at the molecular level. In 2011, two new targeted therapeutic agents, sunitinib and everolimus, were approved by the Food and Drug Administration (FDA). Sunitinib is an inhibitor of multiple tyrosine kinases, and everolimus is an inhibitor of the mammalian target of rapamycin (mTOR) pathway. This review discusses the major signaling pathways that are frequently mutated or deregulated in PNETs, and the implications of molecular alterations for PNET therapy. Biologic therapy through targeting relevant pathways represents a promising approach in the therapy of advanced and unresectable PNETs.

AbstractThe effects of the FUS1gene on the oesophageal carcinoma cell line EC109 are investigated. The messenger RNA (mRNA) expression level of the FUS1gene was detected by a reverse transcription polymerase chain reaction (RT-PCR) technique in the cell lines SHEE, SHEEC and EC109. The full length of the FUS1gene was amplified using a PCR technique from the total RNA of umbilical mesenchymal stem cells. The FUS1gene was cloned into a pSL6-IRESEGFP vector and identified by PCR, digestion and sequencing. The recombinant pSL6-FUS1-IRES-EGFP plasmid was transfected into 293FT cells and the resulting lentivirus was collected. The growth of EC109 cells after transfection with lentivirus containing the FUS1gene was determined by MTT assay and plate colony formation. Expression of the FUS1gene in EC109 cells was weaker than that in SHEE, SHEEC cells and human umbilical vein endothelial cells (HUVEE; used as a control). Transfection efficiency was more than 80% after 48 h. Cell growth assessed by MTT assay was inhibited by about 40% compared with the control group; a finding that was in accordance with the plate colony formation results. The results suggest that the FUS1gene might be a candidate tumour suppressor gene for the treatment of oesophageal carcinoma; however, these results require confirmation in in vivostudies.

Objective: To investigate whether preincisional parecoxib administration can reduce postoperative pain and modulate the inflammatory cytokine response to a greater extent than preincisional parecoxib administration in total hip replacement patients.Methods: Patients were randomized to receive 40 mg parecoxib intravenously either before or after skin incision (preincisional and postincisional groups, respectively). Morphine was administered for postoperative analgesia. Visual analogue pain scale (VAS) scores and morphine consumption were recorded at 1, 6, 18 and 24 h postoperation. Plasma levels of interleukin (IL)-6, IL-8 and tumour necrosis factor-a were measured 30 min before skin incision and 6 h postoperation.Results: Compared with the post - incisional group, VAS pain scores at 1 and 6 h postoperation were significantly lower in the preincisional group. Morphine consumption was significantly lower in the preincisional group at 6, 18 and 24 h postoperation. In both groups, IL-6 and IL- 8 levels increased significantly at 6 h postoperation compared with pre - operation, and the preincisional group had significantly lower levels of IL-6 and IL-8 at 6 h postoperation compared with the postincisional group.Conclusions: Preincisional parecoxib administration reduced postoperative pain and morphine consumption compared with post - incisional administration, and attenuated IL-6 and IL-8 production 24 h after hip replacement surgery.

Poly(aminoester) dendrimers are expected to hold great promise as biodegradable nanocarriers for drug delivery due to their advantageous properties allowing their biodegradability, potentially lower toxicity and possibility of diverse chemical conjugations. The synthetic strategies for constructing such dendrimers include the amine branching method, the ester formation method, the combination of both methods as well as the recently emerging click chemistry based synthesis. We present here an overview on the current state of synthesizing poly(aminoester) dendrimers and discuss the benefits and limitations of each strategy with a view to stimulating a fueled interest in the development of efficient and reliable methodologies to synthesize such dendrimers.

Rubber suspensions are important components in railway vehicles. The offset sandwich mount is a type of rubber spring used on rail vehicles as the primary suspension above the axlebox on a bogie. In this installation, a pair of mounts is arranged within a vee configuration, such that the movements in all planes are controlled by a combined shear and compression displacement. This article evaluates the important aspects in the rubber suspension design when using a higher order material properties in an extreme large deformation. On one hand, using a higher order of material model has enabled prediction of larger deformations that are required for the actual product in the ultimate loading used in rail dynamic environment. On the other hand, using a higher order of material model with full integration elements, however, may mislead the design concept to an incorrect direction. It is important to note that the accuracy of the stress calculation is not guaranteed by a reasonable load–deflection prediction, even validated against a test result. Three methods to check the reliability of the calculated stresses are proposed. The investigation has been validated against a laboratory test. It is suggested that a higher order of material model should be used with reduced integration elements.

Low-energy transfer trajectory is of growing interest in the space community. It is important to choose the patch point of the unstable manifold of the Lyapunov orbit around Sun–Earth L2 and the stable manifold of the Lyapunov orbit around Earth–Moon L2. The main contributions of this study are two areas: (a) designing the optimization model and using evolutionary algorithms to optimize the initial condition and (b) developing effective algorithms for this problem.In this article, an improved differential evolution (DE) algorithm, named adaptive uniform design differential evolution (AUDE), is proposed to solve the Earth–Moon low-energy transfer optimization problem. It incorporates the uniform design technology and the self-adaptive parameter control method into standard DE to accelerate its convergence speed and improve the stability and calculation accuracy. To verify the performance of AUDE, the Earth–Moon low-energy transfer optimization problem and 15 benchmark functions with diverse complexities are employed. The experiment results indicate that the authors' approach is able to find the better one, or at least comparably, in terms of the quality and stability of the final solutions than the other three algorithms. Moreover, it proves that the application of DE algorithm in the Earth–Moon low-energy transfer optimization problem is effective.

Castration-resistant prostate cancer remains incurable and a major cause of mortality worldwide. The absence of effective therapeutic approaches for advanced prostate cancer has led to an intensive search for novel treatments. Emerging nanomedical approaches have shown promising results, in vitro and in vivo, in improving drug distribution and bioavailability, tumor penetration and in limiting toxicity. Nanoscaled carriers bearing finely controlled size and surface properties such as liposomes, dendrimers and nanoparticles have been developed for successful passive and active tumortargeting. Enhanced pharmacokinetics of nanotherapeutics, through improved target delivery and prolonged tissue halflife provides optimal drug delivery that is tumor-specific. Tumor-targeting may be improved through ligand directed delivery systems binding to tumor-specific surface receptors improving cellular uptake through receptor-mediated endocytosis. Recently published data have provided pre-clinical evidence showing the potential of active-targeted nanotherapeutics in prostate cancer therapy; unfortunately, only a few of these therapies have translated into early phase clinical trials development. Hence, progress of active-targeted nanotherapy improving efficiency of site-specific drug delivery is a critical challenge in future clinical treatment of prostate cancer. Exploring specific prostate cell-surface antigens or receptor overexpression may elaborate promising strategies for future therapeutic design. This review presents an overview of some new strategies for prostate cancer active-targeting nanotherapeutics.

AbstractThermal barrier coatings (TBCs), consisting of ceramic topcoat and metallic bond coat, are applied onto Ni-based superalloy hot components in turbine engines to protect the components from high temperature gas. Detrimental phases in the superalloy substrate such as topologically close-packed phase (TCP) and secondary reaction zone (SRZ), resulting from interdiffusion between the bond coat and the substrate, significantly deteriorate the desired mechanical properties of the superalloy substrate. In this paper, a NiRuAl coating was produced onto Ni-based superalloy to inhibit the interdiffusion between the coating and substrate. During the processing, a dense and continuous Ru film of around 4 μm thickness was first electrodeposited onto a K3 superalloy at 70°C using a current density of 1·2 A dm−2. The NiRuAl coating was formed by pack aluminisation of the Ru coated specimen in argon atmosphere at 900°C. The coating shows a two-layered structure: the top layer NiAl and the bottom layer NiRuAl, with the potential functions of diffusion barrier and high temperature oxidation resistance.

Synthetic nucleoside mimics are important candidates for antiviral and anticancer drugs. Ribavirin, the first antiviral nucleoside drug, is unique in its antiviral activity with mutilple modes of action, which are mainly due to its special triazole heterocycle as nucleobase. Additionally, introducing aromatic functionalities to the nucleobase is able to confer novel mechanisms of action for nucleoside mimics. With the aim to combine the special characteristics of unnatural triazole heterocycles with those of the appended aromatic groups on the nucleobases, novel 1,2,4-triazole nucleoside analogs bearing aromatic moieties were designed and developed. The present short review summarizes the molecular design, chemical synthesis and biological activity of these triazole nucleoside analogs. Indeed, the discovery of antiviral and anticancer activities shown by these triazole nucleosides as well as the new mechanism underlying the biological activity by one of the anticancer leads has validated the rationale for molecular design and impacted us to further explore the concept with the aim of developing structurally novel nucleoside drug candidates with new modes of action.

Commercialisation of proton exchange membrane fuel cell (PEMFC) technology depends on high volumetric power density and specific power for a given cost. In the present study, a novel wave‐like architecture for PEMFC stack based on undulate membrane electrode assembles (MEAs) and perforated bipolar plates (PBPs) was presented. Different from conventional plate‐and‐frame architecture, this design increased active area and achieved higher volumetric power density due to undulate MEAs. Moreover, perforated sheet metal was used as bipolar plates so that it could improve specific power.

The interaction of CD40 with CD154 is a pivotal trigger of immune cascade-inducing acute liver failure, however its clinical significance has not been well studied. The present study aimed to investigate the clinical implications of serum-soluble CD154 (sCD154) levels and the expression of CD40 on monocytes in patients with fulminant hepatic failure (FHF). The results showed that serum sCD154 levels and CD40 expression on monocytes were significantly higher in FHF patients than in acute hepatitis (AH) patients and healthy controls, and were also significantly higher in FHF patients who died, compared with those who survived. We conclude that high serum levels of sCD154 may be linked to fatal outcome in patients with severe liver injury and may be a valuable prognostic marker for survival in patients with FHF.

Single Bi 2S 3nanowire devices were fabricated using the focused ion beam technique to deposit Pt electrodes. Repeatable and reliable ohmic contacts were obtained. The devices exhibit outstanding H 2sensing performance that can detect H 2(in N 2) at room temperature with a sensitivity of 22% at 10 ppm (corresponds to 4.0 × 10 −7mol/L). Decorating Pd nanoparticles on the surface of the nanowire does not improve the sensing performance, contrary to most of the existing nanowire (or nanotube) H 2sensors. The sensing mechanism of Bi 2S 3nanowire devices is found to be different from that of other sensors based on nanowires or nanotubes. Experiments on different H 2concentrations and gas pressures suggest that the sensing response is determined mainly by the amount of H 2molecules instead of the proportion of H 2in the mixed gas.

To characterize the magnitude and course of alterations in total and free lamotrigine (LTG) clearance (Cl) during pregnancy and the postpartum period, to assess the impact of therapeutic drug monitoring (TDM) on seizure frequency, to determine the ratio to individual target LTG concentration that is associated with increased seizure risk, and to evaluate maternal postpartum toxicity.

Abstract: A desulfurization experiment was performed with tert-butyl hydroperoxide (t-BuOOH) as the oxidant in the presence of H3PW12O40/SiO2−Al2O3 as the catalyst prepared by the sol-gel method, by using dibenzothiphene (DBT) in petroleum ether as the model compound. This work presents the results for the desulfurization by an oxidation/catalysis/adsorption scheme. The effects of catalyst amounts, t-BuOOH amounts, reaction temperature, and reaction time on the desulfurization efficiency and regeneration performance of the catalyst were studied. It was found that the H3PW12O40/SiO2-Al2O3 catalyst presented a higher maximum desulfurization conversion than SiO2-Al2O3 solids also prepared by the sol-gel method. In addition, the H3PW12O40/SiO2-Al2O3 catalyst showed a higher desulfurization conversion after regeneration with N,N-dimethylamide. It was also found that the oxidation agent t-BuOOH resulted in a higher desulfurization conversion than hydrogen peroxide (H2O2).

A metal‐semiconductor‐metal (M‐S‐M) model for quantitative analysis of current–voltage (I–V) characteristics of semiconducting nanowires is described and applied to fit experimental I–Vcurves of Bi2S3nanowire transistors. The I–Vcharacteristics of semiconducting nanowires are found to depend sensitively on the contacts, in particular on the Schottky barrier height and contact area, and the M‐S‐M model is shown to be able to reproduce all experimentally observed I–Vcharacteristics using only few fitting variables. A procedure for decoupling contact effects from that of the intrinsic parameters of the semiconducting nanowires, such as conductivity, carrier mobility and doping concentration is proposed, demonstrated using experimental I–Vcurves obtained from Bi2S3nanowires and compared with the field‐effect based method.

A concept for quantitative design of sealing glasses was proposed for planar solid oxide fuel cells (SOFC) applications, by which chemical and physical compatibility of a glass with other materials can be predicted through simulation based on a thermodynamic model and a combined model. Using this method, a sealing glass was successfully developed. The thermal expansion coefficient (TEC) of the glass was determined to be 9.9×10-6 K-1 (room temperature to 631°C), which is very close to the value of 10.0 × 10-6 K-1 measured for 8YSZ. Investigations revealed that the sealing glass had very good thermal stability, where the change of the TEC value was within the range of equipment error. The glass was also proved to be chemically compatible with 8YSZ, by the fact that no obvious interfacial reaction was detected after being heat-treated with 8YSZ at 700°C for 500 h.

ZnSe nanobelts and nanowires have been simultaneously synthesized by a closed-space vapor transport technique without using any carrier gas. The products are characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and photoluminescence spectroscopy. It is shown that the nanobelts and nanowires are 50−90 nm in thickness or diameter and hundreds of micrometers in length. Structure analysis indicates that the nanowires take the zinc blende structure, while the nanobelts are single crystalline or bicrystalline wurtzite phase. The as-synthesized products exhibit rich Raman modes and a strong near-band-edge luminescence peak centered at 476 nm. The nanobelts and nanowires grow via a vapor−solid mechanism mediated by a polycrystalline ZnSe film.

A method is developed and shown to be able to shape a carbon nanotube (CNT) into a desired morphology while maintaining its excellent electrical and mechanical properties. Single, freestanding nanotubes are bent by a scanning tunneling microscopy probe, and their morphology is fixed by electron‐beam‐induced deposition (inside a transmission electron microscope) of amorphous carbon on the bent area. It is shown that the mechanical strength of the bent CNT may be greatly enhanced by increasing the amount of carbon glue or the deposition area, and the electrical conduction of the nanotube shows hardly any dependence on the bending deformation or on the deposition of amorphous carbon. Our findings suggest that CNTs might be manipulated and processed as interconnections between electronic devices without much degradation in their electrical conductance, and be used in areas requiring complex morphology, such as nanometer‐scale transport carriers and nanoelectromechanical systems.

In order to understand the effects of the thermophysical properties of the melt on the transport phenomena in the Czochralski (Cz) furnace for the single crystal growth of silicon, a set of global analyses of momentum, heat and mass transfer in small Cz furnace (crucible diameter: 7.2 cm, crystal diameter: 3.5 cm, operated in a 10 Torr argon flow environment) was carried out using the finite-element method. The global analysis assumed a pseudosteady axisymmetric state with laminar flow. The results show that different thermophysical properties will bring different variations of the heater power, the deflection of the melt/crystal interface, the axial temperature gradient in the crystal on the center of the melt/crystal interface and the average oxygen concentration along the melt/crystal interface. The application of the axial magnetic field is insensitive to this effect. This analysis reveals the importance of the determination of the thermophysical property in numerical simulation. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A large flexible laminar shear box was developed for the study of the behavior of saturated sand, especially liquefaction, and soil-structure interactions under two-dimensional earthquake shaking on a shaking table at the National Center for Research on Earthquake Engineering (NCREE) in Taiwan. The shear box is composed of 15 layers of aluminum alloy inner and outer frames with a specimen size of 1880 by 1880 by 1520 mm. The soil at various depths inside the shear box can move, without torsion, according to the two-dimensional wave action induced by the shaking table. The sand specimen inside the shear box is prepared by the wet sedimentation method from a large pluviation device. Instruments are installed to measure the displacements, accelerations, and water pressures at various locations. Shaking table tests of the laminar shear box with and without a sand specimen were conducted. The test results showed that the performance of the biaxial laminar box and the instrumentation are satisfactory.

Individual carbon nanotubes (CNTs) have been cut, manipulated, and soldered via electron‐beam‐induced deposition of amorphous carbon (a‐C) and using a scanning tunneling microscope inside a transmission electron microscope. All CNT structures, including simple tube–tube connections, crossed junctions, T‐junctions, zigzag structures, and even nanotube networks, have been successfully constructed with a high degree of control, and their electrical and mechanical properties have been measured in situ inside the transmission electron microscope. It is found that multiple CNTs may be readily soldered together with moderate junction resistance and excellent mechanical resilience and strength, and the junction resistance may be further reduced by current‐induced graphitization of the deposited a‐C on the junction.

A family of lamellar mesostructured aluminophosphates, denoted Mu-4-Ln (L stands for lamellar, n = 4, 8, 12, 16, the number of carbon atoms for n-alkyl chain) has been prepared through intercalating n-alkylamines into the layered aluminophosphate [(C2H5)2NH2]4[Al8P10O40H2]·[H2O]2.5 (Mu-4) using an ultrasonic method. The intercalation compounds are characterized by XRD, IR, TG, NMR, as well as compositional analyses. The results show that the intact sheet structure of Mu-4 retains while the n-alkylamines are intercalated into the layers. A linear relationship is observed between the interlayer distance and the number of carbon atoms in n-alkyl chains. A possible arrangement of the n-alkylamines in the interlayer space has been proposed using computer simulations.