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Quadrotor unmanned aerial vehicles (UAVs) operating in agricultural fields for aerial photography are susceptible to external disturbances. The disturbances result in trajectory deviation and irregular image overlapping that considerably degrade image quality. Disturbance observers (DOs) are commonly researched for counteracting these effects but may have delays and limitations in handling diverse and high-frequency disturbances. To this end, this work proposes a continuous high-order sliding mode-assisted DO (HSMDO) with limited time convergence characteristics for the estimation of disturbances in systems. The observer consists of a classical nonlinear DO (NDO) and a sliding mode-assisted system (SMAS). The NDO is used to estimate disturbances preliminarily. The SMAS is utilised to assist the NDO in estimating the high-frequency component of disturbances and ensure that the entire DO is finite-time convergent. Finally, the tracking controller is designed on the basis of the HSMDO, which enables UAVs to track the prescribed trajectories under disturbances stably. Simulation results show that the proposed HSMDO can accurately estimate various types of disturbances. Moreover, the tracking controller based on the HSMDO can improve the antidisturbance performance of systems and ensure the trajectory tracking accuracy of UAVs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co@NPC was prepared via one-pot pyrolysis using DES as self-template. • Coupling GOR for boosting H 2 evolution and production of value-added chemicals. • N-doping optimizes the adsorption energy of H 2 O and glucose. • Graphitic N could most effectively promote the glucose oxidation reaction. The electrocatalytic water splitting for hydrogen production is greatly limited by the sluggish anodic OER. Herein, a hybrid of cobalt nanoparticles supported in nitrogen doped porous carbon (Co@NPC) is prepared by using a biomass-based ternary deep eutectic solvent (DES) as precursor and self-templates, which is utlized as bifunctional electrocatalyst for boosting H 2 generation and converting glucose into valuable chemicals simultaneously. Importantly, only a small cell voltage of 1.56 V is required to deliver 10 mA cm−2, which is 180 mV lower than that of overall water splitting. Density functional theory (DFT) calculations confirm that nitrogen doping porous carbon could synergistically optimize adsorption energies of H 2 O (ΔE *H2O) and *H adsorption free energies (ΔG *H), enhancing catalytic activity toward HER. This work highlights the potential application prospects of using glucose oxidation reaction (GOR) instead of OER to promote H 2 generation and product value-added chemicals. [ABSTRACT FROM AUTHOR]

Greenhouse cultivation forms a relatively closed environment for heat preservation in winter, which inevitably leads to a lack of atmospheric CO 2 concentration ([CO 2 ]), and thus low [CO 2 ] level has become a limiting factor for the photosynthesis and growth of greenhouse vegetables. Most cucurbits and solanaceous vegetables are sensitive to low temperature, but it is difficult to keep the optimum root-zone temperature (RZT) for them in greenhouse soil cultivation in winter. Therefore, low RZT is another limiting factor for greenhouse vegetables growth in winter. This study investigated the effects of [CO 2 ], RZT, and their interactions on cucumber yield, growth, photosynthesis, and photosynthate allocation in four open-top chambers for a growth period of 73 days after transplanting. We found elevated RZT increased yield and total dry weight of cucumber plants to a greater extent than elevated [CO 2 ]. We also observed long-term elevated [CO 2 ] limited the increase of net photosynthetic rate (Pn) and decreased the stomatal conductance (Gs) and transpiration rate (Tr) of cucumber plants at ambient RZT, resulted in the photosynthetic acclimation, as illustrated by the significant reduction of nitrogen concentration and the increased concentrations of soluble sugar and starch in leaves. In comparison, the combination of elevated [CO 2 ] and RZT decreased the concentrations of soluble sugar and starch and maintained the nitrogen concentration in leaves, which caused a higher Pn, Gs and Tr. Meanwhile, more soluble sugar and starch were allocated from leaves to roots due to the higher root respiratory under elevated [CO 2 ] and RZT treatment. Moreover, elevated RZT could facilitate the mineral nutrients absorption by roots and the upward transportation because of the larger root system and higher Tr. Therefore, elevated RZT could offset the decrease in Pn and improve Gs and Tr under elevated [CO 2 ], which indicated an alleviation of the photosynthetic acclimation of cucumber plants exposed to long-term elevated [CO 2 ]. [Display omitted] • Root-zone temperature (RZT) had a greater impact on cucumber dry weight than CO 2 concentration ([CO 2 ]). • Long-term elevated [CO 2 ] caused photosynthetic acclimation at ambient RZT. • Elevated RZT was favorable for transporting photosynthate from leaves to roots. • Elevated RZT promoted the nitrogen absorption by roots and upward transportation. • Elevated RZT alleviated the photosynthetic acclimation of cucumber plants. [ABSTRACT FROM AUTHOR]

In this article, based on the structural properties of the coefficient matrix obtained through the discretization of constrained optimal control problems under the time-harmonic parabolic equation, we propose and compare two types of algorithms, namely the Optimized PU (OPU) method and the optimized double-step (ODS) method. It can be theoretically proven that both of these iterative methods have a convergence rate of 0.1716, which can even be optimized to reach 0.0396. Additionally, we demonstrate that these two methods avoid the common drawback of many methods in terms of parameter selection, where the parameters often depend on the matrix's eigenvalues. The convergence rate of 0.1716 can be easily achieved through a single constant setup in the proposed two methods. Furthermore, we also compare the algorithmic complexity of the OPU method, the ODS method, and the latest RSS-like method in each step of the iterative process, which demonstrates that the OPU method and ODS method exhibit advantages in computational storage or calculation complexity. Finally, to demonstrate the effectiveness of our proposed optimized iterative methods and the validity of our theoretical findings, we conduct numerical experiments. The results provide strong empirical support for the efficiency and reliability of these methods. [ABSTRACT FROM AUTHOR]

Aims: To investigate the antidepressant role of oligodendrocyte‐derived exosomes (ODEXs)‐containing sirtuin 2 (SIRT2) and the underlying mechanism both in vivo and in vitro. Methods: Oligodendrocyte‐derived exosomes isolated from mouse serum were administered to mice with chronic unpredictable mild stress (CUMS)‐induced depression via the tail vein. The antidepressant effects of ODEXs were assessed through behavioral tests and quantification of alterations in hippocampal neuroplasticity. The role of SIRT2 was confirmed using the selective inhibitor AK‐7. Neural stem/progenitor cells (NSPCs) were used to further validate the impact of overexpressed SIRT2 and ODEXs on neurogenesis and synapse formation in vitro. Results: Oligodendrocyte‐derived exosome treatment alleviated depressive‐like behaviors and restored neurogenesis and synaptic plasticity in CUMS mice. SIRT2 was enriched in ODEXs, and blocking SIRT2 with AK‐7 reversed the antidepressant effects of ODEXs. SIRT2 overexpression was sufficient to enhance neurogenesis and synaptic protein expression. Mechanistically, ODEXs mediated transcellular delivery of SIRT2, targeting AKT deacetylation and AKT/GSK‐3β signaling to regulate neuroplasticity. Conclusion: This study establishes how ODEXs improve depressive‐like behaviors and hippocampal neuroplasticity and might provide a promising therapeutic approach for depression. [ABSTRACT FROM AUTHOR]

The minimum variation time-scale (MVT) and spectral lag of hundreds of X-ray bursts (XRBs) from soft gamma-ray repeater (SGR) J1935+2154 were analysed in detail for the first time in our recent work, which are important probes for studying the physical mechanism and radiation region. In this work, we investigate their differential and cumulative distributions carefully and find that they follow power-law models. Besides, the distributions of fluctuations in both parameters follow the Tsallis q -Gaussian distributions and the q values are consistent for different scale intervals. Therefore, these results indicate that both parameters are scale-invariant, which provides new parameters for the study of self-organized criticality systems. Interestingly, we find that the q values for MVT and spectral lag are similar with duration and fluence, respectively. [ABSTRACT FROM AUTHOR]

Aqueous zinc (Zn) ion batteries (AZIBs) have not yet fulfilled their talent of high safety and low cost since the anode/electrolyte interface (AEI) has long been impeded by hydrogen evolution, surface corrosion, dendritic growth, and by‐product accumulation. Here, the hydrolysis of solid buffers is elaborately proposed to comprehensively and enduringly handle these issues. Take 2D layered black phosphorus (BP) as a hydrolytic subject. It is reported that the phosphoric acid generated by hydrolysis in an aqueous electrolyte produces a zinc phosphate (ZPO) rich solid electrolyte interphase (SEI) layer, which largely inhibits the dendrite growth, surface corrosion, and hydrogen evolution. Meanwhile, the hydrolytic phosphoric acid stabilizes the pH value near AEI, avoiding the accumulation of alkaline by‐products. Notably, compared with the disposable ZPO engineerings of anodic SEI pre‐construction and electrolyte additive, the hydrolysis strategy of BP can realize a dramatically prolonged protective effect. As a result, these multiple merits endow BP modified separator to achieve improved stripping/plating stability toward Zn anode with more than ten times lifespan enhancement in Zn||Zn symmetrical cell. More encouragingly, when coupled with a V2O5·nH2O cathode with ultra‐high loadings (34.1 and 28.7 mg cm−2), the cumulative capacities are remarkably promoted for both coin and pouch cells. [ABSTRACT FROM AUTHOR]

White matter injury (WMI) is one of the most serious complications associated with preterm births. Damage to oligodendrocytes, which are the key cells involved in WMI pathogenesis, can directly lead to myelin abnormalities. L‐ascorbyl‐2‐phosphate (AS‐2P) is a stable form of vitamin C. This study aimed to explore the protective effects of AS‐2P against chronic hypoxia‐induced WMI, and elucidate the underlying mechanisms. An in vivo chronic hypoxia model and in vitro oxygen–glucose deprivation (OGD) model were established to explore the effects of AS‐2P on WMI using immunofluorescence, immunohistochemistry, western blotting, real‐time quantitative polymerase chain reaction, Morris water maze test, novel object recognition test, beaming‐walking test, electron microscopy, and flow cytometry. The results showed that AS‐2P resulted in the increased expression of MBP, Olig2, PDGFRα and CC1, improved thickness and density of the myelin sheath, and reduced TNF‐α expression and microglial cell infiltration to alleviate inflammation in the brain after chronic hypoxia. Moreover, AS‐2P improved the memory, learning and motor abilities of the mice with WMI. These protective effects of AS‐2P may involve the upregulation of protein arginine methyltransferase 5 (PRMT5) and downregulation of P53 and NF‐κB. In conclusion, our study demonstrated that AS‐2P attenuated chronic hypoxia‐induced WMI in vivo and OGD‐induced oligodendrocyte injury in vitro possibly by regulating the PRMT5/P53/NF‐κB pathway, suggesting that AS‐2P may be a potential therapeutic option for WMI. [ABSTRACT FROM AUTHOR]

This work presents an efficient solution for automatic gain control (AGC) loop in ZigBee transceiver compatible to IEEE 802.15.4 standard. The design is based on a RF (Radio Frequency) and linear IF (Intermediate Frequency) chain where the signal amplification is done in the RF front-end blocks and analog VGAs (variable gain amplifiers). The gains of the RF block and VGA are digitally controlled by the DAGC (Digital AGC) block to ensure that the ADC (Analog-to-Digital Converter) operates inside its dynamic range. Feedback loop architecture is employed for the advantage of high linearity due to its inherent characteristic. The whole AGC loop has been integrated in the ZigBee transceiver which was fabricated in a 0.18μm CMOS technology. The AGC loop achieves a dynamic range of about 95dB with the gain error of less than ±0.5dB. The two-channel VGAs and peak detectors occupy an area of 1.5mm×0.4mm and dissipate 1.71mW from a single 1.8V power supply. The DAGC has been integrated in the digital baseband processor and occupies an area of about 0.4mm×0.4mm. The max gain lock time of the AGC loop is about 1.25μs. [ABSTRACT FROM AUTHOR]

A novelfamily of organoboron compounds 1–4with bright near-infrared (NIR) emissions in the crystallinestate was synthesized. They show a morphology-dependent emission “ON”and “OFF” feature and volatile acid/base-induced fluorescencesaltation which allow the realization of reversible solid-state fluorescenceswitching in the NIR region by totally different procedures: mechanicalgrinding/solvent annealing and acid/base vapor fuming. [ABSTRACT FROM AUTHOR]

Micro-sensors are fabricated by co-electrospinning InO and SnO nanofibers on the substrates of SiO/Si with interdigitated Pt signal electrodes. The total sensor area is 1.36 mm × 0.55 mm and the active area is only 0.63 mm × 0.55 mm. Excellent NH sensing properties are obtained based on the sensors at room temperature. The sensitivity is at most 28 when the sensors are exposed to NH of 10 ppm. The response time is 8 s or so and the recovery time is nearly 2 s. Not only fine selectivity, but also long-time stability is obtained. The results not only demonstrate the obtained micro-sensors are very promising devices for NH detection, but also show a possible route for large-scale NH sensor fabrication at the industrial level. [ABSTRACT FROM AUTHOR]

The performance of the feedback control system is of central importance in the measurement of the Newton's gravitational constant G with angular acceleration method. In this paper, a PID (Proportion-Integration-Differentiation) feedback loop is discussed in detail. Experimental results show that, with the feedback control activated, the twist angle of the torsion balance is limited to 7.3 x 10-7 rad√Hz at the signal frequency of 2mHz, which contributes a 0.4 ppm uncertainty to the G value. [ABSTRACT FROM AUTHOR]

Abstract: The Carboniferous to Permian period marks an important transition from accretion to collision in the East Junggar terrane, NW China. Field and Well Fuqian-1 well core data from the Zhaheba depression provide a better window for understanding the magmatic process during this period and its implications for the continental growth of Central Asia. Field investigations reveal structural features characterized by NE–SW compression, with lithology composed of basic and intermediate-felsic volcanic rocks and pyroclastic rocks. The core samples from Well Fuqian-1 show dominantly basalt, basaltic andesite, dacite and minor pyroclastic rocks. We report zircon SHRIMP U–Pb ages of 276.0–279.8Ma from rhyolites and zircon LA–ICP-MS U–Pb ages of 315.4–317.4Ma from dacite and basaltic andesite. Our data suggest that the volcanic rocks from surface exposures and the well cores of Well Fuqian-1 formed in the Early Permian and the Late Carboniferous, respectively. The Late Carboniferous mafic rocks have geochemical characteristics similar to the intercalated Early Permian felsic rocks. The mafic rocks show low initial 87Sr/86Sr (0.703162–0.703783) and high εNd(t) (5.5–7.5), enrichment in LREE and some LILEs (such as Rb and Th) as well as HFSEs (such as Zr, Y), and depletion in Nb, Ta and Ti. Furthermore, they also display lower Sm/Th (1.6–8.4) and higher Th/Y (0.03–0.12) ratios than those of MORB, and variable Th/Zr (0.004–0.016), Ba/Th (61–839), Ba/La (6.13–48.77) and Ba/Nb (10–101) ratios. The geochemical data suggest that these rocks were derived dominantly from a 5–10% partial melting of a mainly garnet-rich with minor spinel-bearing Iherzolite mantle source metasomatized by slab-derived fluids. The felsic rocks are rich in silica (SiO2 =57.43–78.07%) and alkalis (K2O+Na2O=5.33–9.28%) and possess high TFe2O3 (0.70–6.95%) contents and Ga/Al ratios, and low CaO (0.18–5.11%) and MgO (0.13–2.02%) contents. They represent typical high–medium-K calc-alkaline A-type rhyolite with enrichment of LREE and HFSE (Zr, Hf) and depletion of Ba, Sr, Eu, Nb and Ta. These rocks display high εNd(t) (6.9–7.3) and εHf(t) (10.3–14.6) values and young crustal model ages (348–557Ma). Integrating regional geological data from the East Junggar terrane and the available data from the proximal ophiolite belt, we propose that an arc–arc or arc–continent post-collisional setting in the Zhaheba area commenced at ca. 317Ma. The Late Carboniferous–Early Permian felsic and mafic magmas were derived from the partial melting of the juvenile mafic lower crust and subcontinental lithospheric mantle metasomatized by pre-Carboniferous subduction-related fluids through asthenospheric upwelling. This post-collisional event suggests that vertical accretion played an important role not only in the Late Carboniferous–Early Permian continental growth of the East Junggar, but also in the final evolutionary phase of the accretionary orogen. [Copyright &y& Elsevier]

Novel α-Ag3VO4 nanostructures have been successfully synthesized via a facile and repeatable precipitation method by using n-BA as precipitant and complexing agent. Photocatalytic property tests for decomposition of RhB demonstrate that the as-prepared nanostructures have enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

In an attempt to improve the antitumor activity of homocamptothecins (hCPTs), a series of novel 20-O-linked hCPT ester derivatives were first designed and synthesized based on a synthetic route, by which hCPTs are acylated with different substituted phenoxyacetic acid ester derivatives. Most of the derivatives were assayed for in vitro cytotoxicity against six human cancer cell lines KB, KB/VCR, A549, HCT-8, Bel7402, and A2780, and most of the assayed compounds exhibited good antiproliferative activity on these tumor cell lines especially on KB. [ABSTRACT FROM AUTHOR]

Four-coordinate organoboron compounds with rigid π-conjugated structures are intensely luminescent and have high carrier mobility which enables them to be applied in optoelectronics including organic light-emitting diodes (OLEDs), organic field-effect transistors, as well as photoresponsive, sensory and imaging materials. Various chelate ligands and boron moieties have been explored to construct proper electronic structures and suitable molecular arrangements, which play important roles on the photophysical and electronic properties of the four coordinate boron compounds. These efforts have produced a number of fascinating molecules, some of which have exhibited high performance as light emitting materials. In this article, we provide an overview of the progress in the molecular construction of four-coordinate organoboron compounds with an emphasis on their applications in OLEDs. [ABSTRACT FROM AUTHOR]

Large-scale Sn and/or S doped Cu3Sb1−xSnxSe4−ySy (x = 0.02, 0.04, 0.06 and 0.10; y = 0, 0.5) nanoparticles were first prepared through a low-temperature co-precipitation route. The effects of Sn doping on the thermoelectric properties of the Cu3SbSe4-based materials were explored. Due to the improved power factor from optimizing the carrier concentration and the reduced lattice thermal conductivity from enhanced phonon scattering at the grain interfaces, the maximum thermoelectric figure of merit, ZTmax, obtained here reached 1.1 for the co-doped Cu3Sb0.94Sn0.06Se3.5S0.5 material, which is the largest value reported for Cu3SbSe4-based materials. [ABSTRACT FROM AUTHOR]

A series of aluminum alkyl complexes nacnacRAlMe2 (2a–2h) bearing aliphatic N-substituted β-diketiminate ligands (nacnacRH = N,N′-dialkyl-2-amino-4-iminopent-2-enes), were prepared from the reaction of trialkyl aluminum and the corresponding β-diketimines. All these aluminum complexes were characterized by NMR, elemental analysis and HRMS spectroscopy. The molecular structures of complexes 2a, 2c and 2h were confirmed by single-crystal X-ray diffraction. These aluminum alkyl complexes show notable activity towards the ring-opening polymerization of ε-caprolactone in the absence and presence of alcohol, and the resulting polymers have narrow molecular weight distributions. [ABSTRACT FROM AUTHOR]

Fast radio bursts (FRBs) are extremely strong radio flares lasting several micro- to milliseconds and come from unidentified objects at cosmological distances, most of which are only seen once. Based on recently published data in the CHIME/FRB Catalog 1 in the frequency bands 400–800 MHz, we analyze 125 apparently singular FRBs with low dispersion measure (DM) and find that the distribution of their luminosity follows a lognormal form according to statistical tests. In our luminosity measurement, the FRB distance is estimated by using the Macquart relation that was obtained for 8 localized FRBs, and we find it still applicable for 18 sources after adding the latest 10 new localized FRBs. In addition, we test the validity of the luminosity distribution up to the Macquart relation and find that the lognormal-form feature decreases as the uncertainty increases. Moreover, we compare the luminosity of these apparent nonrepeaters with that of the previously observed 10 repeating FRBs also at low DM, noting that they belong to different lognormal distributions with the mean luminosity of nonrepeaters being two times greater than that of repeaters. Therefore, from the two different lognormal distributions, different mechanisms for FRBs can be implied. [ABSTRACT FROM AUTHOR]

[Display omitted] Carbon dots (CDs) emerge as promising luminescent materials for potential applications in optoelectronics on basis of their merits including low cost, eco-friendliness and strong, color-tunable photoluminescence (PL). However, the research on solid-state emissive CDs is still at the primary stage because of the aggregation-caused quenching (ACQ) of PL and their poor film-formation ability. In this work, we produce CDs with branched-polyethylenimine (b-PEI) chemically functionalized on the surfaces. The thus newly synthesized P-CDs successfully overcome the bottleneck of ACQ effect and display efficient red and NIR emission in aggregate state. Under the excitation of 520 nm, a strong red emission (maxima of 640 nm) with a high photoluminescence quantum yield (PLQY) of 21% was observed for the P-CDs in neat film. Moreover, this design strategy endows the P-CDs with good film-formation ability via solution spin-coating, which significantly increases its value for the film-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

The changing origins of the late Paleozoic calc-alkaline magmatic rocks in the Bogda tectonic belt (BTB) during the Late Carboniferous–Early Permian bring new insights into the subduction-collision processes in the eastern Tianshan region. Based on the geochronological, geochemical and Sr–Nd–Hf isotopic data, a systematic study was conducted on the Late Carboniferous andesite and the Early Permian diabase dyke and MME-bearing granite porphyry from the Dalonggou area in the northern BTB. The ~310 Ma andesites are featured by low initial 87Sr/86Sr ratios, positive ε Nd (t) (+4.4 to +5.3) and ε Hf (t) (+10.2 to +13.6) values, enrichment in light rare earth elements and large ion lithophile elements, and depletion in Nb and Ta. They are interpreted as the products of partial melting of a metasomatized depleted mantle wedge in an extensional arc environment. The ~290 Ma diabase dykes exhibit a nearly flat REE pattern, low Fe/Mn ratios (53–59), and high TiO 2 and Zr contents and mantle potential temperatures (1471–1480 °C). They were derived from a sub-slab asthenospheric mantle with the involvement of the lithospheric mantle. The MMEs were produced by fractional crystallization of the diabase magmas, and the host granite porphyries were formed by magma mixing between melts derived from the newly-formed lower crust and mantle. These results indicate that the BTB represented a backarc/intra-arc rift during the Late Carboniferous that was transitioned to a post-collisional rift in the Early Permian, witnessing a dynamic switch from rollback to detachment of the subducted North Tianshan oceanic slab. Combined with the variation of magma sources with time, we propose that the collision between the Dananhu-Harlik arc and the Central Tianshan arc and the closure of the North Tianshan Ocean occurred at ca. 310–302 Ma. Such a scenario agreed well with coeval tectonics in the Karamaili area, shedding light on the late Paleozoic spatio-temporal tectonic evolution in the eastern Tianshan. • Late Carboniferous and Early Permian magmatic rocks in the BTB display diverse origins. • Two stages of rift events were recognized in the BTB during the late Paleozoic. • The BTB underwent a tectonic switch from backarc/intra-arc to post-collisional setting. • The closure of the North Tianshan Ocean took place in the late Carboniferous. [ABSTRACT FROM AUTHOR]

By skillfully introducing a conjugate electron donating ring into the g-C 3 N 4 framework, the as-prepared 3 wt% PPD/CN sample not only narrows the bandgap of g-C 3 N 4 , but also absorbs more solar light up to 600 nm. As a result, the optimal sample exhibited hydrogen escape under orange light (600 nm) and bare g-C 3 N 4 had almost no such performance. [Display omitted] • Benzene ring doping in the specific site of the network of g-C 3 N 4 was obtained. • It still has photoactivity that g-C 3 N 4 barely has under the orange light. • The 3 wt% PPD/CN can effectively cover more sufficient photo flux (λ = 600 nm). • The benzene ring incorporation of g-C 3 N 4 enhanced photogenerated carrier separating. Grafting π-conjugated donor units into graphitic carbon nitride (g-C 3 N 4) represents a promising alterative to improve its light absorption range and charge transfer kinetics. To this end, we here report an efficient intramolecular g-C 3 N 4 -based conjugated copolymers via the one-spot thermal copolymerization for not only reduces the bandgap to 2.56 eV and thus expand the visible-light harvesting capability, but also accelerates the separation ability of photogenerated excitons. Consequently, the copolymer of 3 wt% p-phenylenediamine with melamine exhibits extraordinary hydrogen (H 2) evolution rate of 1040 μmol g−1 h−1 under visible light. Interestingly, it still shows hydrogen production (5.29 μmol g−1 h−1) at λ = 600 nm (orange light). Systematic characterizations have proved that the optimal sample has high photocatalytic activity, due to rapid charge transfer kinetics and exciton separation. Our work sheds light on a molecular design to regulate charge-transfer dynamics among of polymeric semiconductors towards efficient solar-to-H 2 production. [ABSTRACT FROM AUTHOR]

CdV2O6 and Cd2V2O7 were successfully synthesized by a simple hydrothermal process. The effects of the hydrothermal temperature and pH on the phase transition between CdV2O6 and Cd2V2O7 were investigated in detail. That the Cd2V2O7 phase could transform into CdV2O6 was attributed to polymerization of vanadate in an acidic environment as the V/O ratio increased as the pH decreased. V2O74- was stable in a neutral or alkaline environment at an identical hydrothermal temperature, therefore, the Cd2V2O7 phase was obtained after hydrothermal treatment for 24 h. Because the degree of hydrolysis of NH4Cl increased with increasing temperature in the solution, the increased temperature accelerated the speed of the pH decrease. Therefore, the hydrothermal temperature played an important part in the phase transition between CdV2O6 and Cd2V2O7. CdV2O6 and Cd2V2O7 showed high photocatalytic activity for the degradation of methylene blue under visible-light irradiation. [ABSTRACT FROM AUTHOR]

In the work presented here, well-dispersed ferric giniite microcrystals with controlled sizes and shapes are solvothermally synthesized from ionic-liquid precursors by using 1- n-butyl-3-methylimidazolium dihydrogenphosphate ([Bmim][H2PO4]) as phosphate source. The success of this synthesis relies on the concentration and composition of the ionic-liquid precursors. By adjusting the molar ratios of Fe(NO3)3 ⋅9H2O to [Bmim][H2PO4] as well as the composition of ionic-liquid precursors, we obtained uniform microstructures such as bipyramids exposing {111} facets, plates exposing {001} facets, hollow spheres, tetragonal hexadecahedron exposing {441} and {111} facets, and truncated bipyamids with carved {001} facets. The crystalline structure of the ferric giniite microcrystals is disclosed by various characterization techniques. It was revealed that [Bmim][H2PO4] played an important role in stabilizing the {111} facets of ferric giniite crystals, leading to the different morphologies in the presence of ionic-liquid precursors with different compositions. Furthermore, since these ferric giniite crystals were characterized by different facets, they could serve as model Fenton-like catalysts to uncover the correlation between the surface and the catalytic performance for the photodegradation of organic dyes under visible-light irradiation. Our measurements indicate that the photocatalytic activity of as-prepared Fenton-like catalysts is highly dependent on the exposed facets, and the surface area has essentially no obvious effect on the photocatalytic degradation of organic dyes in the present study. It is highly expected that these findings are useful in understanding the photocatalytic activity of Fenton-like catalysts with different morphologies, and suggest a promising new strategy for crystal-facet engineering of photocatalysts for wastewater treatment based on heterogeneous Fenton-like process. [ABSTRACT FROM AUTHOR]

Abstract: CdTe@SiO2 fluorescent nanospheres were synthesized by heating reflux method. Infrared spectra support the structural formation mechanism of the CdTe@SiO2 composite nanospheres. The CdTe@SiO2 composite nanospheres were characterized by means of SEM, TEM, IR, nitrogen adsorption isotherm, fluorescence spectra and electroluminescence spectra, etc. It was found that both pH value and reflux time played important roles in growth and quantum yield of CdTe@SiO2 fluorescent nanospheres. CdTe@SiO2 fluorescent nanospheres were fabricated to be a single electrode light-emitting diode prototype. The electroluminescence spectra and Commission International de L’Eclairage remained almost the same over a range of operation voltages, and it meant the light-emitting diodes had better color stability. So CdTe@SiO2 fluorescent nanospheres could provide a potential application in light-emitting diode. [Copyright &y& Elsevier]

Abstract: Illnesses from Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella have been associated with the consumption of numerous produce items. Little is known about the effect of consumer handling practices on the fate of these pathogens on celery. The objective of this study was to determine pathogen behavior at different temperatures under different storage conditions. Commercial fresh-cut celery was inoculated at ca. 3logCFU/g onto either freshly cut or outer uncut surfaces and stored in either sealed polyethylene bags or closed containers. Samples were enumerated following storage for 0, 1, 3, 5, and 7 days when held at 4 °C or 12 °C, and after 0, 8, and 17 h, and 1, and 2 days when held at 22 °C. At 4 °C, all populations declined by 0.5–1.0logCFU/g over 7 days. At 12 °C, E. coli O157:H7 and Salmonella populations did not change, while L. monocytogenes populations increased by ca. 0.5logCFU/g over 7 days. At 22 °C, E. coli O157:H7, Salmonella, and L. monocytogenes populations increased by ca. 1, 2, or 0.3logCFU/g, respectively, with the majority of growth occurring during the first 17 h. On occasion, populations on cut surfaces were significantly higher than those on uncut surfaces. Results indicate that populations are reduced under refrigeration, but survive and may grow at elevated temperatures. [Copyright &y& Elsevier]

The adsorption and photoelectrocatalytic characteristics of four different kinds of organic compounds ( d-fructose, glutamic acid, fumaric acid, and nicotinic acid) on TiO nanotube arrays (TNAs) were investigated using a thin-layer cell, wherein the compounds were rapidly and exhaustively oxidized. The photogenerated current-time ( I- t) profiles were found to be related to the adsorption, the degradation rate, and the reaction mechanism. The relationship between the initial organic compounds concentrations and photocurrent peaks ( I) fit the Langmuir type adsorption model well, thereby confirming that the adsorption of organic compounds on TNAs was via monolayer adsorption. The adsorption equilibrium constant was obtained from the Langmuir equation. The results indicate that the adsorption performance of the organic compounds on TNAs were in the following order: nicotinic acid < d-fructose < glutamic acid < fumaric acid. The degradation of organic compounds on TNAs was classified as either easy or difficult based on the time of complete mineralization ( t) of the organic samples under an equal holes consumption; the degree of degradation were as follows: fumaric acid < d-fructose < glutamic acid < nicotinic acid. The photoelectrocatalytic characteristics of the organic compounds on TNAs were also discussed by analyzing the changes in the I- t profiles. [ABSTRACT FROM AUTHOR]

Purpose: A20 gene functions in negative immunoregulation and its SNP is related to SLE disease. But its expression level in immune cells from SLE patients is still unclear. The aim of this study is to investigate whether the expression of A20 is associated with pathogenesis of SLE. Methods: Real-time transcription-polymerase chain reaction analysis (RT-PCR) was used to determine expression of A20 mRNA in peripheral blood mononuclear cells (PBMC) from 37 patients with SLE and 32 healthy controls. Results: A20 expression was decreased in SLE patients compared with healthy controls ( p = 0.0133). The expression level of A20 gene negatively correlated with the SLE disease activity index (SLEDAI) ( r =−0.4661, p = 0.0036) and erythrocyte sedimentation rate (ESR) ( r =−0.5222, p = 0.0009). Furthermore, SLE patients with nephritis had a lower expression of A20 than those without nephritis ( p = 0.0188). Conclusions: Our results suggest that the insufficient expression of A20 gene in PBMC may take part in the pathogenesis of SLE disease. [ABSTRACT FROM AUTHOR]

Abstract: Novel visible-light-induced γ-Fe2O3@SiO2@Ce-doped-TiO2 core–shell nanocomposite photocatalysts capable of magnetic separation have been synthesized by a facile sol–gel and after-annealing process. The as-obtained core–shell nanocomposite is composed of a central γ-Fe2O3 core with a strong response to external fields, an interlayer of SiO2, and an outer layer of Ce-doped TiO2 nanocrystals. UV–vis spectra analysis indicates that Ce doping in the compound results in a red-shift of the absorption edge, thus offering increased visible light absorption. We show that such a γ-Fe2O3@SiO2@Ce-doped-TiO2 core–shell nanocomposite with appreciated Ce doping amount exhibits much higher visible-light photocatalytic activity than bare TiO2 and undoped γ-Fe2O3@SiO2@TiO2 core–shell nanocomposite toward the degradation of rhodamine B (RhB). Moreover, the γ-Fe2O3@SiO2@Ce-doped-TiO2 core–shell nanocomposite photocatalysts could be easily separated and reused from the treated water under application of an external magnetic field. [Copyright &y& Elsevier]

The view on velocity structures in molecular clouds and their relationship with magnetic fields (B field) has evolved during the past decade from almost no correlation to highly parallel. Our numerical simulations suggest a more nuanced picture: Depending on whether the self-gravity is dynamically dominant, the velocity field can be governed by either contraction (at high densities) or turbulence (at low densities), and their anisotropies will tend to be either perpendicular or parallel, respectively, to the B fields. High-density regions are always embedded in the low-density fore/background, so the velocity behaviors from lines of sight (LOSs) with high column densities will be a mixture of orthogonal anisotropies, which can be hard to interpret and necessitates zooming in onto certain LOS scales to better characterize localized behaviors. We tested and confirmed the above prediction with CO observations of the Taurus molecular cloud. [ABSTRACT FROM AUTHOR]

2D Zn3(OH)2V2O7·2H2O/NH4V4O10 nanobelts are synthesized by a simple hydrothermal route. This is the first report on the transformation of Zn3(OH)2V2O7·2H2O/NH4V4O10 (ZnVO/NVO) nanobelts into Zn3(OH)2V2O7·2H2O-based materials by an in situ electrochemical conversion, which act as an active cathode for high capacity and long cycling life aqueous rechargeable zinc ion batteries. By tuning the hydrothermal reaction time, the ZnVO and NVO content in the ZnVO/NVO can be controlled. The ZnVO/NVO nanobelts with a ZnVO content of 24.1% exhibit superior electrochemical performance with a maximum discharge capacity of 337 mA h g−1 at a current density of 0.5 A g−1. At a high current density of 10.0 A g−1, the ZnVO/NVO cathode still exhibits a maximum discharge capacity of 187 mA h g−1, and keeps a reversible capacity of 176 mA h g−1 with a maximum capacity retention of 94% after 2000 cycles. The synergistic effect of intercalated Zn2+ and NH4+ ions as well as structural water provides the cathode materials with excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (SC-CO2) fracturing technology has the advantages of CO2 storage and waterless fracturing and has great application potential in the development of unconventional oil and gas resources. However, the low viscosity of SC-CO2 limits the development of this technology. This paper investigates the synergistic effect of nanomaterials on a developed thickener (HBD-2, high branched D4H). The research results show that among the five micro/nanomaterials Cu-BTC, SiO2, MCC, MWCNTs, and TiO2, only SiO2 has a good synergistic effect on the HBD-2/SC-CO2 system, and significantly improves its thickening, temperature resistance, temperature resistance and shear resistance. At 60s−1, 305.15 K and 10 MPa, 5 wt.% HBD-2 + 1 wt.% SiO2 increased the apparent viscosity of SC-CO2 to 5.82 mPa·s(The viscosity of 5 wt.% HBD-2 under the same conditions is 4.48 mPa·s). The apparent viscosity of SC-CO2 is positively correlated with pressure and SiO2 dosage and negatively correlated with temperature and shear rate. The SiO2/HBD-2 system can effectively avoid clay swelling and can change the water wetness on the core surface to neutral wettability. In addition, we also studied the mechanism of SiO2 in HBD-2/SC-CO2 thickening system by RDF(radial distribution function). The results show that the introduction to SiO2 shifts the peak position of the system to the left and enhances the peak intensity. The macroscopic manifestation is the enhancement of the apparent viscosity of HBD-2/SC-CO2.This paper proves the feasibility of nanomaterials to synergize SC-CO2, and provides a new thread for the research and development of SC-CO2 thickeners in the future. [ABSTRACT FROM AUTHOR]

AbstractGene-modified skin grafts, produced through gene transfer to human keratinocyte stem cells, offer the possibility of therapeutic benefit for inherited skin diseases. We have previously described efficient lentiviral vector–mediated gene transfer to keratinocyte stem cells and the generation of human skin grafts for the inherited skin disease, Netherton syndrome, which arises due to mutations in serine protease inhibitor Kazal-type 5(SPINK5). Vectors incorporating an internal murine retroviral–derived promoter [spleen focus-forming virus (SFFV)] in combination with a codon-optimized SPINK5transgene supported high levels of reconstitution and robust correction of skin architecture. Subsequent longer-term experiments have uncovered unanticipated silencing phenomena, with loss of SPINK5gene expression over time. The inadvertent introduction of CpG sites during codon optimization appears to have rendered vectors susceptible to silencing due to methylation across the promoter–transgene boundary. Substitution of the methylation-susceptible SFFV promoter with a 572-bp minimal human involucrin promoter (INVOp), which encodes very few CpG sites, prevented repression of the SPINK5transgene and resulted in durable and highly compartment-specific reconstitution of lympho-epithelial Kazal-type–related inhibitor (LEKTI) in human skin grafted onto immunodeficient mice. We conclude that skin grafts modified with lentiviral vectors encoding INVOp offer a suitable platform for therapeutic gene therapy in Netherton syndrome, and our experience highlights unanticipated effects of transgene codon optimization. [ABSTRACT FROM AUTHOR]

Background: Progressive hepatic fibrosis is the eventual cause of liver cirrhosis. Doppler ultrasound has been used to detect hemodynamic changes that are known to be present during the pre-cirrhotic stages of hepatic fibrogenesis. However, the relationship between the Doppler ultrasound parameters and the impairment of the liver function has not been fully investigated. The purpose of this study was to explore the hepatic function reserve and its relationship with the hepatic hemodynamics in a rabbit model of liver fibrosis using Doppler ultrasound. Methods: A prospective study was performed. Sixty healthy New Zealand rabbits were included in this study. Eleven of them served as controls and were normally fed and provided with water drink; the rest of 49 rabbits that served as fibrosis group were normally fed but provided with 1.2 g/L of thioacetamide to create liver fibrosis model. Doppler measurements were performed in the portal trunk, proper hepatic artery and proper splenic artery. The hepatic circulation index (HCI) was calculated. Hepatic function reverse was evaluated by measuring the indocyanine green clearance and retention rate at 15 min (ICG R15) test. Portal venous pressure (PVP) was measured using the portal vein punctuation equipment. Results: HCI was significantly decreased and PVP increased in the advanced fibrotic stage (F4) compared to mild and moderate fibrotic stage (F1-3), respectively (p<0.05). PVP and ICG R15 in the fibrotic group were significantly higher than that in the control group (ICG: 0.209±0.086 vs. 0.093±0.023, p<0.01). Within the fibrotic groups, PVP was higher in advanced fibrotic stage (F4) than those in mild (F1-2) or moderate (F3) fibrotic stages (p<0.05). Both HCI and PVP correlated well with ICG R15 (r = ?0.890, and r = 0.780, p <0.01). Conclusions: Hepatic function reserve closely relates to the hepatic hemodynamics in the rabbit model of liver fibrosis. Doppler Ultrasound could be reliably used to assess the hepatic function reserve and hemodynamic changes in different stages of liver fibrosis. [ABSTRACT FROM AUTHOR]

Abstract: High-performance (Bi2Te3) x (Sb2Te3)1−x bulk materials were prepared by combining fusion technique with spark plasma sintering, and their thermoelectric properties were investigated. The electrical resistivity and Seebeck coefficient increase greatly and the thermal conductivity decreases significantly with the increase of Bi2Te3 content, which leads to a great improvement in the thermoelectric figure of merit ZT. The maximum ZT value reaches 1.33 at 398 K for the composition of 20%Bi2Te3-80%Sb2Te3 with 3% (mass fraction) excess Te. [Copyright &y& Elsevier]

ZnWO4nanorod photocatalysts with various aspect ratios were synthesized by a hydrothermal method. The aspect ratio of the ZnWO4nanorods was governed by the hydrothermal temperature and pH value. ZnWO4nanorod photocatalysts showed highly efficient photocatalytic activity for the degradation of methylene blue under ultraviolet light irradiation. The photocatalytic activity and the effective separation of photogenerated electron–hole pairs were promoted by the increasing aspect ratio of the ZnWO4nanorods. The amount of electron donors in the ZnWO4increased with the aspect ratio of ZnWO4, which was in good agreement with photocurrent results. The enhancement of photocurrent density and photocatalytic activity resulted from the reduction of charge-transfer resistance and capacitive reactance, which were deduced by the high aspect ratio of ZnWO4nanorods. [ABSTRACT FROM AUTHOR]

Four phenanthroimidazole derivatives (a: 1,2-diphenyl-1H-phenanthro[9,10-d]imidazole; b: 2-phenyl-1-p-tolyl-1H-phenanthro[9,10-d]imidazole; c: 1-phenyl-2-p-tolyl-1H-phenanthro[9,10-d]imidazole; d: 1,2-di-p-tolyl-1H-phenanthro[9,10-d]imidazole) were synthesized and their single crystal structures, photophysical, electrochemical and mobility properties were carefully studied. Taking advantage of the thermal stability and the hole transporting (HT) ability, the highly efficient Alq3-based organic light-emitting diodes (OLEDs) have been achieved by employing the compounds a–d as a functional layer between NPB (4,4-bis(N-(1-naphthyl)-N-phenylamino)biphenyl) and Alq3 (tris(8-hydroxyquinoline)aluminium) layers. For the device of [ITO/NPB/d/Alq3/LiF/Al], a maximum luminous efficiency (LE) of 8.1 cd A−1 was obtained with a maximum brightness of 65 130 cd m−2, which exhibited much higher efficiency compared to the device with structure of [ITO/NPB/Alq3/LiF/Al]. The results demonstrated not only an alternative idea to design novel HT materials, but also a convenient way to improve the performance of the NPB/Alq3-based devices by introduction of a suitable organic buffer layer. [ABSTRACT FROM AUTHOR]

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in the world. Its innovative engineering concept and design pave a new road to realize a huge single dish in the most effective way. FAST also represents Chinese contribution in the international efforts to build the square kilometer array (SKA). Being the most sensitive single dish radio telescope, FAST will enable astronomers to jump-start many science goals, such as surveying the neutral hydrogen in the Milky Way and other galaxies, detecting faint pulsars, looking for the first shining stars, hearing the possible signals from other civilizations, etc. The idea of sitting a large spherical dish in a karst depression is rooted in Arecibo telescope. FAST is an Arecibo-type antenna with three outstanding aspects: the karst depression used as the site, which is large to host the 500-meter telescope and deep to allow a zenith angle of 40 degrees; the active main reflector correcting for spherical aberration on the ground to achieve a full polarization and a wide band without involving complex feed systems; and the light-weight feed cabin driven by cables and servomechanism plus a parallel robot as a secondary adjustable system to move with high precision. The feasibility studies for FAST have been carried out for 14 years, supported by Chinese and world astronomical communities. Funding for FAST has been approved by the National Development and Reform Commission in July of 2007 with a capital budget ~ 700 million RMB. The project time is 5.5 years from the commencement of work in March of 2011 and the first light is expected to be in 2016. This review intends to introduce the project of FAST with emphasis on the recent progress since 2006. In this paper, the subsystems of FAST are described in modest details followed by discussions of the fundamental science goals and examples of early science projects. [ABSTRACT FROM AUTHOR]

Netherton syndrome (NS) is a debilitating congenital skin disorder caused by mutations in the SPINK5 gene encoding the lymphoepithelial Kazal-type-related inhibitor (LEKTI). It is characterized by defective keratinization, recurrent infections, and hypernatraemic dehydration with a mortality rate of about 10% in the first year of life. Currently, there are no curative treatments for NS. We have developed a HIV-1 based, self-inactivating lentiviral vector to express SPINK5 in keratinocytes as part of an ex-vivo gene therapy strategy for NS. High transduction efficiency was achieved in NS keratinocytes and reconstitution of LEKTI expression was confirmed in previously deficient cells. These genetically corrected keratinocytes were further tested in an in vitro organotypic culture (OTC) system and in vivo mouse/human skin engraftment model. Results showed correction of epidermal architecture in both OTCs and regenerated skin grafts. Importantly, the results from corrected skin grafts indicated that even where detectable LEKTI expression was restored to a limited numbers of cells, a wider bystander benefit occurred around these small populations. As LEKTI is a secreted protein, the genetically modified graft may provide not only an immediate local protective barrier, but also act as a source of secreted LEKTI providing a generalized benefit following ex-vivo gene therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A –OH and −C N grafted g-C 3 N 4 is first used as a photocatalytic disinfectant. • The −C N can act as oxygen adsorptioncenters to accelerate the surface reaction. • The hydrophilic interface favors electron transfer and surface catalytic reaction. • The HAC-CN shows an excellent performance in inactivating E. coli and S. aureus. Exploration of cost-effective and high-performing photocatalysts for bacteria disinfection remains a difficult task. Herein, the hydroxyl (–OH) and cyano groups (–C N) co-modulated graphitic carbon nitride (g-C 3 N 4) was first employed as a photocatalytic disinfectant. Systematic characterizations have proved that the abundant –OH and –C N can not only obtain favorable hydrophilicity but also promote the transfer of photogenerated charge carriers. Meanwhile, the –C N can serve as the oxygen adsorption center and the photogenerated electrons accumulation center to accelerate the surface reaction, thus realizing the rapid generation of reactive oxygen species. As expected, the optimal sample can inactivate 6.76-log of Escherichia coli (E. coli) within 60 min and 7.14-log of Staphylococcus aureus (S. aureus) within 90 min under visible light, which shows the most superior disinfection rate of S. aureus and the relatively excellent inactivation ability of E. coli , as compared to other recently reported monolithic g-C 3 N 4 -based photocatalysts. This work provides new insights into maximizing the dynamic behavior of photogenerated charge carriers and constructing novel photocatalytic disinfectants. [ABSTRACT FROM AUTHOR]

Data from in vitro plasma protein binding experiments that determine the fraction of protein-bound drug are frequently used in drug discovery to guide structure design and to prioritize compounds for in vivo studies. However, we consider that these practices are usually misleading, because in vivo efficacy is determined by the free (unbound) drug concentration surrounding the therapeutic target, not by the free drug fraction. These practices yield no enhancement of the in vivo free drug concentration. So, decisions based on free drug fraction could result in the wrong compounds being advanced through drug discovery programmes. This Perspective provides guidance on the application of plasma protein binding information in drug discovery. [ABSTRACT FROM AUTHOR]

Green tea, a popular drink with beneficial health properties, is a rich source of polyphenols that have a wealth of physiological activities. The purpose of the present study was to develop a microwave-assisted extraction (MAE) of green tea polyphenols. MAE of tea phenols from green tea was investigated through orthogonal array design. The content of total phenols in tea infusions was determined using UV/vis spectrophotometric methods. Four factors (microwave intensity, microwave irradiate time, microwave irradiate number of times and tea/water ratio) have a substantial impact on the extraction. The extraction conditions of tea polyphenols are optimized, and the order of importance that influenced the extraction rate was found to be: microwave radiate time>microwave intensity>tea/water ratio>radiate number of times, and the optimal performance of extraction was obtained under microwave intensity 600 W, microwave radiate time 3 min and microwave radiate number of times once with tea/water ratio 1:20.MAE offers important advantages over conventional methods, such as shorter extraction times, substantial savings of energy and a reduced environmental burden. [ABSTRACT FROM AUTHOR]

Abstract: We present a facile strategy for the shape-controlled synthesis of F-substituted hydroxyapatite (FHAp) microcrystals based upon using a combination of Na2EDTA and citric acid (CA). Novel, well-defined FHAp microcrystals of various shapes, such as hexagonal disks with predominant (0001) faces, hexagonal shuttles, hexagonal prisms, icosahedrons, and hexagonal microrods with tunable aspect ratios, were fabricated. In particular, FHAp hollow microcrystals with tunable shapes were fabricated directly without using any additional template. The central features of our approach are the use of both Na2EDTA and CA as two distinct chelating reagents and the use of substitution ions (F−) itself as a growth inhibitor for the FHAp crystals. F− ions were found to play a critical role in the formation of hexagonally shaped FHAp microcrystals, and in the one-pot formation of hollow microcrystals, which relies on the addition order of F− ions in the synthesis. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the synthesis of discrete free-standing porphyrin nanoparticles using a reprecipitation method, which is an approach widely used in the synthesis of organic nanoparticles. The crystallization of tin(IV) porphyrin is investigated thoroughly by changing the concentration of aqueous solution for the first time. The morphology is then probed using transmission electron microscopy and atomic force microscopy. It is found that the morphology of the porphyrin nanoparticles changed dramatically in this process. The initial characterization of the porphyrin nanoparticles is analyzed using dynamic light scattering. Further analyses of their aggregation modes are conducted by spectroscopic methods such as ultraviolet–visible (UV–vis) absorption, fluorescence spectra and X-ray diffraction (XRD). Their UV–vis spectra characteristics are discussed in detail. On the basis of the findings, the influence of these peripheral substituents on the sol formation and the aggregation mode is discussed. [Copyright &y& Elsevier]

Abstract: Breakdown of immune homeostasis contributes to the pathogenesis of systemic lupus erythematosus (SLE). Tumor necrosis factor α induced protein-8 like-2 (TIPE2) is a very recently identified immune homeostasis maintaining gene. We wondered whether TIPE2 is associated with SLE. We examined the mRNA expression levels of TIPE2 and myxoma resistance protein (MX) 1 (one of type I interferon inducible genes) in peripheral blood mononuclear cells (PBMC) from 39 SLE patients and 35 healthy controls by real-time reverse transcription-polymerase chain reaction analysis (RT-PCR). The TIPE2 mRNA expression was significantly down-regulated in SLE patients compared with healthy controls (P =0.0004), while the MX1 mRNA expression was increased in SLE patients compared with healthy controls (P =0.0031). Furthermore, the TIPE2 mRNA expression levels negatively correlate with the SLE disease activity index (SLEDAI) (r =−0.5016, P =0.0011) and the MX1 mRNA expression levels (r =−0.8083, P <0.0001) in all the SLE patients. These results indicate that decreased expression of TIPE2 gene is closely associated with SLE and suggest an important role for TIPE2 gene in the pathogenesis of SLE. [Copyright &y& Elsevier]

Abstract: We herein report a DNA sensor for the sequence-specific DNA detection by using glucose oxidase-based biocatalyzed electrochemiluminescence and non-fouling surfaces. In this design, a glucose oxidase-labeled sandwich-type DNA sensor was built on a non-fouling surfaces made of a mixed self-assembled monolayers (SAMs) incorporating thiolated oligonucleotides and oligo(ethylene glycol) (OEG) thiols (SH-DNA/OEG). The sequence-specific DNA sensing was accomplished by the electrochemiluminesce (ECL) signal of luminol with the in-situ generated H2O2. The protein-resistant non-fouling surfaces significantly suppressed the non-specific adsorption of enzyme label on electrode and reduced the background noise of this sensor. This sensor was able to detect as little as 1pM of target DNA in pure buffer matrix. In complicated biological fluids such as human serum, this non-fouling platform-based sensor also revealed superior performance over conventional sandwich-type DNA sensors with mercaptohexanol (MCH)-coated surfaces. This strategy combines the high sensitivity of enzymatic amplified ECL and protein-resistant non-fouling platform, which is expected to be extended to a range of biological detection. [Copyright &y& Elsevier]

Abstract: Targeted drug delivery system of traditional Chinese medicine (TCM) refers to those using different carriers to make the effective parts or monomer extracted from TCM or natural medicine into agents which can directly concentrate on the target site. This system is an ideal delivery approach and has became a hot spot in the field of TCM pharmaceutical research since it can improve the pharmacological effects and reduce the adverse reactions. This paper reviews literatures on TCM targeted agents which were published in the past 10 years. In accordance with the different carriers, four types of agents, liposome, nanoparticle, microsphere, and emulsion are analyzed. Liposomes were studied most profoundly and a variety of new types of liposomes was developed on the basis of the traditional liposomes. Using natural or synthetic polymer materials to carry drugs, nanoparticles and microspheres can promote the drug through the blood–brain barrier and enhance its bioavailability. Emulsion has lymphatic affinity and the drug is coated in the internal phase, which can protect the drugs from hydrolysis. All these delivery agents are proved to be effective ways to improve the clinical efficacy of drugs, and each is discussed in detail with examples. At present, TCM targeted agents are still in the exploratory stage and many problems need to be solved. Especially, it is a huge challenge to research the targeted delivery systems for the effective parts of Chinese medicines and compound prescriptions, and the paper gives a particular discussion on this point. In the future, more attention should be paid to the research on the particle agents of TCM effective parts, and the development of new carrier materials in order to enhance the overall quality of TCM targeted agents. [Copyright &y& Elsevier]

Four novel cyclic peroxide glucosides 15a, 15b, 16a, and 16b, optically pure analogs of shuangkangsu (1), which is an anti-virus natural product with an unusual skeleton isolated from the buds of Lonicera japonica Thunb, were first synthesized totally in six steps including cycloaddition of furan with diethyl acetylenedicarboxylate and glycosylation. [ABSTRACT FROM AUTHOR]

Permeability data from MDR1-MDCKII and PAMPA-BBB assays were compared to data from in situ brain perfusion to evaluate the accuracy of in vitro assays in predicting in vivo blood–brain barrier (BBB) permeability. PAMPA-BBB significantly correlated to in situ brain perfusion, however, MDR1-MDCKII had no correlation with in situ brain perfusion. PAMPA-BBB also significantly correlated with MDR1-MDCKII. The differential correlation of PAMPA-BBB and MDR1-MDCKII to in situ brain perfusion appears to be mainly due to the difference in membrane characteristics rather than binding to brain tissue. The MDR1-MDCKII cell membrane has lower ratios of: phospholipid to cholesterol, unsaturated to saturated acyl chains, and phosphatidyl-choline (PC) to sphingomyelin (SM) than brain endothelial cells, making it a poor passive permeability model for BBB. The BBB is more hydrophobic, rigid, and less fluidic than MDR1-MDCKII cell membrane. PAMPA-BBB more closely matches the BBB membrane in these characteristics and is a more accurate passive diffusion permeability model for BBB than MDR1-MDCKII. PAMPA-BBB is high throughput, low cost and has good prediction of in vivo BBB permeability, and therefore, it is a valuable tool in drug discovery to screen compounds for the rate of brain penetration. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:1980–1991, 2009 [ABSTRACT FROM AUTHOR]