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Uranium is a key resource for the development of the nuclear industry, and extracting uranium from the natural seawater is one of the most promising ways to address the shortage of uranium resources. Herein, a semiconducting covalent organic framework (named NDA-TN-AO) with excellent photocatalytic and photoelectric activities was synthesized. The excellent photocatalytic effect endowed NDA-TN-AO with a high anti-biofouling activity by generating biotoxic reactive oxygen species and promoting photoelectrons to reduce the adsorbed UVI to insoluble UIV , thereby increasing the uranium extraction capacity. Owing to the photoinduced effect, the adsorption capacity of NDA-TN-AO to uranium in seawater reaches 6.07 mg g-1 , which is 1.33 times of that in dark. The NDA-TN-AO with enhanced adsorption capacity is a promising material for extracting uranium from the natural seawater.

A multicomponent metallic glass (MG) with highly efficient and anomalous durability for catalyzing water splitting is reported. The outstanding performance of the MG catalyst contributed by self-optimized active sites originates from the intrinsic chemical heterogeneity and selective dealloying on the disordered surface; thus, a new mechanism for improving the durability of catalysts is uncovered.

Phase transition in thermoelectric (TE) material is a double-edged sword-it is undesired for device operation in applications, but the fluctuations near an electronic instability are favorable. Here, Sb doping is used to elicit a spontaneous composition fluctuation showing uphill diffusion in GeTe that is otherwise suspended by diffusionless athermal cubic-to-rhombohedral phase transition at around 700 K. The interplay between these two phase transitions yields exquisite composition fluctuations and a coexistence of cubic and rhombohedral phases in favor of exceptional figures-of-merit zT. Specifically, alloying GeTe by Sb

A record high zT of 2.2 at 740 K is reported in Ge0.92Sb0.08Te single crystals, with an optimal hole carrier concentration ≈4 × 1020 cm-3 that simultaneously maximizes the power factor (PF) ≈56 µW cm-1 K-2 and minimizes the thermal conductivity ≈1.9 Wm-1 K-1. In addition to the presence of herringbone domains and stacking faults, the Ge0.92Sb0.08Te exhibits significant modification to phonon dispersion with an extra phonon excitation around ≈5-6 meV at Γ point of the Brillouin zone as confirmed through inelastic neutron scattering (INS) measurements. Density functional theory (DFT) confirmed this phonon excitation, and predicted another higher energy phonon excitation ≈12-13 meV at W point. These phonon excitations collectively increase the number of phonon decay channels leading to softening of phonon frequencies such that a three-phonon process is dominant in Ge0.92Sb0.08Te, in contrast to a dominant four-phonon process in pristine GeTe, highlighting the importance of phonon engineering approaches to improving thermoelectric (TE) performance.

Summary To what extent the genomes of different species belonging to one genus can be diverse and the relationship between genomic differentiation and environmental factor remain unclear for oceanic bacteria. With many new bacterial genera and species being isolated from marine environments, this question warrants attention. In this study, we sequenced all the type strains of the published species of Glaciecola, a recently defined cold-adapted genus with species from diverse marine locations, to study the genomic diversity and cold-adaptation strategy in this genus. The genome size diverged widely from 3.08 to 5.96 Mb, which can be explained by massive gene gain and loss events. Horizontal gene transfer and new gene emergence contributed substantially to the genome size expansion. The genus Glaciecola had an open pan-genome. Comparative genomic research indicated that species of the genus Glaciecola had high diversity in genome size, gene content and genetic relatedness. This may be prevalent in marine bacterial genera considering the dynamic and complex environments of the ocean. Species of Glaciecola had some common genomic features related to cold adaptation, which enable them to thrive and play a role in biogeochemical cycle in the cold marine environments.

Compared with other T-helper subsets, Th17 cell numbers are very low in human blood but become elevated in chronic inflammatory diseases. In this study, we investigated mechanisms that may explain the frequent involvement of Th17 cells in autoimmune diseases such as uveitis. We compared Th17 and Th1 subsets and found that Th17 cells expressed lower IL-2 levels during Ag-priming and this correlated with their decreased susceptibility to activation-induced cell death (AICD). However, complete depletion of IL-2 with IL-2 neutralizing antibodies rendered Th17 cells as susceptible to apoptosis as Th1 cells, suggesting that the low levels of IL-2 produced by Th17 cells conferred survival advantages to this subset. We describe here a Th17 subtype that constitutively produces very low levels of IL-2 (Th17-DP). The Th17-DP population increased dramatically in the blood and retina of mice during experimental autoimmune uveitis, indicating their potential involvement in the etiology of uveitis. We further show that the majority of the memory Th17 cells in human blood are Th17-DP and are targets of daclizumab, an IL-2R antibody used in treating recalcitrant uveitis. Thus, Th17 cells may persist in tissues and contribute to chronic inflammation by limiting IL-2 production to levels that cannot provoke IL-2-induced AICD yet are sufficient to promote Th17 homeostatic expansion.

1. Nitric oxide (NO), a gas transmitter, modulates many physiological processes, including the central regulation of cardiovascular activity. However, the mechanisms underlying the regulation of cardiovascular activity remain relatively unexplored. In the present study, we hypothesized that central NO-dependent sympathetic inhibition is mediated by activation of adenosine A(2A) receptors (A(2A)R) and inhibition of acetylcholine (ACh) release in the rostral ventrolateral medulla (RVLM). 2. L-Arginine (L-Arg; an NO donor; 100 nmol/100 nL) was microinjected into the RVLM of male Sprague-Dawley rats and heart rate variability (HRV) was assessed as an index of cardiac sympathovagal balance. Following microinjection of L-Arg, decreases were seen in mean arterial pressure (MAP), heart rate (HR) and the ratio of the low- to high-frequency components (LF/HF) of HRV. Pretreatment of rats with SCH58261 (40 pmol/60 nL into the RVLM), a competitive antagonist of the A(2A) R, attenuated these effects. 3. Western blot analysis and ELISA revealed that adenosine and A(2A)R levels increased in the RVLM following L-Arg microinjection, whereas ACh and muscarinic M(1) receptor levels decreased significantly, in parallel with the cardiovascular responses to L-Arg microinjection. The decrease in ACh levels was abolished by SCH58261 pretreatment. 4. Microinjection of N(G)-nitro-L-arginine methyl ester (a non-selective inhibitor of NO synthase; 15 nmol/100 nL) into the RVLM significantly increased MAP, HR and sympathetic activity, as evidenced by HRV (LF, HF and the LF/HF ratio were all increased). 5. The results indicate that the central NO/NO synthase system in the RVLM may modulate cardiovascular activity by activating the A(2A)R, which subsequently inhibits activation of the muscarinic M(1) receptor.

Neuronal or photoreceptor deficit observed in uveitis and multiple sclerosis derives in part from inability to control inflammatory responses in neuroretina or brain. Recently, IL-27 was found to play a role in suppressing experimental autoimmune uveitis and experimental autoimmune encephalomyelitis, two animal models that share essential pathological features of human uveitis and multiple sclerosis, respectively. However, the mechanism by which interleukin-27 (IL-27) inhibits central nervous system (CNS) inflammation is not clear. In this study we have investigated mechanisms that mitigate or curtail intraocular inflammation (uveitis) and examined whether inhibitory effects of IL-27 are mediated locally by neuroretinal cells or by regulatory T cells. We show here that microglia cells in the neuroretina constitutively secrete IL-27 and its expression is up-regulated during uveitis. We further show that photoreceptors constitutively express IL-27 receptor and respond to IL-27 signalling by producing anti-inflammatory molecules, IL-10 and suppressor of cytokine signalling 1 (SOCS1) through signal transducer and activator of transcription 1 (STAT1) -dependent mechanisms. Moreover, STAT1-deficient mice produced reduced amounts of IL-27, IL-10 and SOCS1 and developed more severe uveitis. Surprisingly, IL-10-producing regulatory T cells had marginal roles in suppressing uveitis. These results suggest that suppression of intraocular inflammation might be mediated through endogenous production of IL-27 and IL-10 by retinal cells, whereas SOCS proteins induced by IL-27 during uveitis may function to protect the neuroretinal cells from the toxic effects of pro-inflammatory cytokines. Targeted delivery of IL-27 into immune privileged tissues of the CNS may therefore be beneficial in the treatment of CNS inflammatory diseases, such as uveitis and multiple sclerosis.

The reactions of dilithium salt of trans-1,2-bis(trimethylsilylamino)cyclohexane with anhydrous lanthanide trichlorides LnCl3 (Ln=Yb, Nd) in THF afforded the dianionic binuclear tricycles of lanthanide chlorides {Li(THF)3[LnCl(µ2-trans-1,2-(NSiMe3)2C6H10)((2-Cl)]}2·2THF (Ln=Yb 1, Nd 2) in moderate yields. Both of the bridged complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Crystal structural analysis shows that the two complexes are the analogues which have a tricyclic framework built by two bridged lanthanide metals, four nitrogens and four carbons from two diamide ligands. Each lanthanide metal coordinates to three nitrogen atoms and two chlorines to form a distorted trigonal bipyramid and connects with a lithium by a bridging chlorine.

UNLABELLED This study aimed to explore the therapeutic mechanism of intravenous immunoglobulin (IVIG) for Kawasaki disease (KD). Peripheral blood lymphocytes (PBLs) obtained from 26 children with KD and 20 age-matched healthy children were stimulated with anti-CD3 monoclonal antibody (mAb), and the percentage of apoptotic cells and DNA fragmentation were assayed at 0, 12, 24, 48 and 72 h in vitro. The patients were divided into two groups: one treated with aspirin combined with IVIG (n = 16) and one treated with aspirin alone (n = 10). PBLs were stimulated by phytohaemagglutinin to evaluate the lymphocyte proliferative response. Compared with normal controls, the apoptotic cell percentage and the DNA fragmentation were markedly decreased (p < 0.001) and delayed in PBLs from KD patients. After IVIG treatment, the decreased percentage of apoptotic cell and delayed DNA fragmentation were restored to the state of the normal controls, accompanied by a fast clinical remission compared with the aspirin-alone group. The lymphocyte proliferative response was also decreased 3-5 d after IVIG therapy (p < 0.001). CONCLUSION The results suggest that decreased PBL apoptosis may be involved in the pathogenesis of KD. The therapeutic mechanism of IVIG in KD may be partially due to the reversal of the inhibited lymphocyte apoptosis, and may have implications for other autoimmune diseases with inefficient lymphocyte apoptosis.

The relationship between the observed order of reaction of photodegradation of nitrofurazone solution and the illuminance of incident light as well as the concentration of the solution was studied. In the studies, the solutions of three concentrations were exposed to light with three different illuminance values, respectively. The results indicated that the observed order of reaction was increased with the decrease of concentration, when the illuminance was kept constant, and with the increase of illuminance when the concentration was kept constant. The observed order of reaction of photodegradation of nitrofurazone solution depended on both the concentration of the drug and the illuminance of the incident light.

The influence of both light and heat on the stability of nitrofurazone aqueous solution was studied. Results show that in either heating experiments or the exposure to light at high temperatures, the degradation rate obeyed zero-order kinetics. The total rate constant ktotal caused by both light and heat can be divided into two parts: ktotal=kdark+klight, where kdark and klight are the degradation rate constants caused by heat and light, respectively. The klight can be expressed as klight=Alight·exp(−Ea,light/RT)·E, where E is the illuminance of light, and Alight and Ea,light,light both are experimental constants. The values of these kinetic parameters were determined based on the experiments in the dark and upon exposure to three different light sources. Results show that the values of Alight and Ea,light varied with the light source. To save time, labor, and drugs, exponential heating experiments were employed and compared with the isothermal experiments. Results indicated that kinetic parameters obtained by exponential heating experiments are comparable to those obtained by isothermal experiments either in the dark or upon exposure to light.

A series of open-framework aluminoborates (ABOs) [M(dien)2][AlB6O11(OH)] (M=Co (I a), Ni (I b), Cd (I c), Zn (I d); dien=diethylenetriamine) and [M(en)3][AlB7O12(OH)2]⋅ (H2O)0.25 (M=Co (II a), Ni (II b); en=ethylenediamine) have been made under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, UV/Vis and fluorescence spectroscopy, powder X-ray diffraction, single-crystal X-ray diffraction, and nonlinear optical determination. These compounds were classified as two structural types: Type I (I a–d) contains AlO4 tetrahedra and B6O11(OH) clusters, which link to form a new 3D framework with 7-/9-ring helical channels and large 13-ring channels; whereas type II (II a,b) is composed of AlO4 tetrahedra, chainlike B4O6(OH)2 tetramer, and crablike B6O12 clusters, which interconnect to form other new 3D frameworks with 8-ring helical channels, rare 16-ring double-helical channels, and larger odd 15-ring channels. These compounds represent the first examples of 3D ABOs templated by transition-metal complexes (TMCs). I c,d present good second harmonic generation (SHG) properties. UV/Vis spectral investigation indicates that I a–d and II a,b are wide-band-gap semiconductors.