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Lymphatic capillaries develop discontinuous cell-cell junctions that permit the absorption of large macromolecules, chylomicrons, and fluid from the interstitium. While excessive vascular endothelial growth factor 2 (VEGFR2) signaling can remodel and seal these junctions, whether and how VEGFR3 can alter lymphatic junctions remains incompletely understood. Here, we use lymphatic-specific Flt4 knockout mice to investigate VEGFR3 signaling in lymphatic junctions. We show that loss of Flt4 prevents specialized button junction formation in multiple tissues and impairs interstitial absorption. Knockdown of FLT4 in human lymphatic endothelial cells results in impaired NOTCH1 expression and activation, and overexpression of the NOTCH1 intracellular domain in Flt4 knockout vessels rescues the formation of button junctions and absorption of interstitial molecules. Together, our data reveal a requirement for VEGFR3 and NOTCH1 signaling in the development of button junctions during postnatal development and may hold clinical relevance to lymphatic diseases with impaired VEGFR3 signaling. [Display omitted] • VEGFR3 is required for the development of lymphatic capillary button junctions • VEGFR3 is not required for maintaining button junctions after their formation • Failure to form buttons impedes the absorption of interstitial molecules • NOTCH1 signaling can rescue button formation and function in the absence of VEGFR3 Lymphatic capillaries form discontinuous junctions called buttons to enable absorption of interstitial contents. Jannaway et al. show that vascular endothelial growth factor receptor 3 (VEGFR3) expression is required for the formation of button junctions and that NOTCH1 signaling can fully rescue button formation in the absence of VEGFR3. [ABSTRACT FROM AUTHOR]

In this work, carbon/SiO 2 composites, using amylose and tetraethyl orthosilicate (TEOS) as raw materials, were successfully prepared by a facial hydrothermal carbonization process. The carbon/SiO 2 composites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Energy Dispersive Spectroscopy (EDS), transmission electron microscope (TEM), N 2 adsorption and Thermogravimetric (TG) analysis. The composites, which were made up of amorphous SiO 2 and amorphous carbon, were found to have hierarchical porous structures. The mass ratios of amylose and SiO 2 and the hydrothermal carbonization time had significant effects on the morphology of the composites, which had three shapes including monodispersed spheres, porous pieces and the nano-fibers combined with nano-spheres structures. The adsorption performance of the composites was studied using Pb 2+ as simulated contaminants from water. When the mass ratio of amylose and SiO 2 was 9/1, the hydrothermal time was 30 h and the hydrothermal temperature was 180 °C, the adsorption capacity of the composites achieved to 52 mg/g. Experimental data show that adsorption kinetics of the carbon/SiO 2 composites can be fitted well by the Elovich model, while the isothermal data can be perfectly described by the Langmuir adsorption model and Freundlich adsorption model. The maximum adsorption capacity of the carbon/SiO 2 composites is 56.18 mg g −1 . [ABSTRACT FROM AUTHOR]

Abstract: The living environment of marine plankton and benthos has been affected by reclamation projects. The investigation of living environment of marine plankton and benthos in Tianjin Harbor Industrial Zone was carried out three times from 2006 to 2008. The results showed that the Shannon-Weaver diversity index of phytoplankton and zooplankton decreased from 3.01 to 1.71 and 1.7 to 0.58, respectively. In addition, the diversity index of Shannon-Weaver of benthos decreased to zero from 1.28. The results showed that reclamation projects would change the living environment of marine organism, decrease the diversity of biology and change the structure of community. [ABSTRACT FROM AUTHOR]

Soil respiration (SR) has been demonstrated to be affected by nitrogen (N) enrichment. However, most studies examine the effect of N enrichment on SR using only two levels of N treatments (i.e. control vs N enrichment). Current understanding of SR responses to varying rates of N enrichment remains unclear. A field manipulative experiment with eight levels of N addition (0, 1, 2, 4, 8, 16, 32, 64 g N m−2 yr−1) was performed to examine SR responses to N enrichment rates in a temperate steppe of northern China. A nonlinear decrease in SR along N addition gradient was observed in the temperate steppe. N addition decreased SR mainly through reducing soil moisture in this study. These findings facilitate accurate estimation of soil C flux in the scenario of intensified N enrichment. • Nitrogen addition has a negative effect on soil respiration. • Soil respiration shows a non-linear decrease with increased nitrogen addition. • Water availability drives soil respiration response to nitrogen addition. [ABSTRACT FROM AUTHOR]

The Middle−Upper Xixiangchi Formation of the Sichuan Basin consists of mixed carbonates and siliciclastics. The carbonates are dominated by dolomitized lime-mudstones and dolo–grainstones of shallow warm-water environments. Petrographic examination of carbonates reveals two types of dolomite: (i) fabric retentive dolomicrite (D1, micritic to near-micritic, 4–50 μm) and (ii) fabric-destructive dolomite (eu-to subhedral crystals with cloudy cores and clear rims, 50–300 μm). The mean ∑REE values of D1 (15.3 ± 6.3 ppm) and D2 (14.6 ± 7.1 ppm) and the nearly identical mean PAAS-normalized patterns that coincide at some points, suggest an origin from similar parent fluids that were not dramatically changed by water-rock interaction through basinal sedimentary rocks. The estimated Sr/Ca molar ratios of D1 (0.0043–0.0055) parent fluids and their estimated δ18O values imply an origin from a mixture of meteoric and seawaters, which is also consistent with the petrographic evidence. The partially coinciding normalized REE pattern of D2 with that of the earlier D1 suggests that the latter was formed at a mid-burial setting rather than deep burial, which is consistent with higher homogenization temperatures of primary two-phased fluid inclusions retained in D2 (T h = 118.1 ± 5.3 °C). Therefore, D1 is suggested to have formed (1) during a penecontemporaneous period that resulted from a slight evaporative pumping effect within a near-surface diagenetic environment, and/or (2) during post-penecontemporaneous or penecontemporaneous seepage-reflux dolomitization, induced by sea-level fluctuations, during early stages of diagenesis at near-surface conditions. D2 formed likely through the recrystallization of D1 or a continuation of reflux dolomitization of the same precursor at mid-burial rather than deep burial settings. • Origins of D1 and D2 dolomites are reflected by their geochemical compositions. • Dolomitizing fluids were derived from slightly evaporated seawater and basinal brines. • Similar parent fluids of D1 and D2 are reflected by their nearly identical PAAS-normalized REEs patterns. • Recrystallization of D1 likely accounts for comparable δ18O values with D2. [ABSTRACT FROM AUTHOR]

The exploitation of solid hydrogen storage materials is an important part of the large-scale application of hydrogen energy. However, Metal agglomeration is one of the main reasons that restrict the hydrogen storage performance of carbon-based hydrogen storage materials. Herein, we develop Ti-decorated boron doped porous graphene as a novel hydrogen storage material based on first-principles calculations. The geometry and electronic structure of Ti-decorated porous graphene with and without boron doped are calculated. Doping boron in porous graphene (PG) can significantly increase the metal-substrate interaction and prevents the formation of Ti-metal clusters. The Ti atom-decorated boron-doped porous graphene (Ti–B/PG) system can stably adsorb sixteen hydrogen molecules with a gravimetric hydrogen uptake of 8.58 wt%. The thermodynamic calculations prove a high usable capacity of the material, at the adsorbing and desorbing conditions of 25 °C, 30 atm and 100 °C, 3 atm. The excellent hydrogen capacity, good recyclability, and desirable desorption capacity of Ti–B/PG make it a very prospective material for hydrogen storage. [Display omitted] • Boron doping can prevent the formation of Ti-metal clusters and enhance hydrogen adsorption. • Gravimetric H 2 uptake is 8.58 wt%, higher than DOE's 2025 target of 5.5 wt%. • Thermodynamic analysis also proves a high usable capacity of hydrogen. • Ti-decorated boron-doped porous graphene is a potential material for hydrogen storage. [ABSTRACT FROM AUTHOR]

Urotensin II (UII) is a kind of fish somatostatins cyclic peptide, which was originally extracted from the caudal neurosecretory system (CNSS). The system of UII and UII receptor (UIIR) has been reported to have multiple physiological regulatory functions, such as cardiovascular control, osmoregulation, and lipid metabolism. However, the effect of UII and UIIR on the ovarian development has not been covered. This study investigated the expression pattern of UII and UIIR in the ovarian follicles and explored their impact on ovarian development in olive flounder Paralichthys olivaceus. The results showed that the highest UII and UIIR mRNA levels were observed at stage II and stage III follicles during ovarian development, respectively. In situ hybridization revealed that a strong signal of UII was expressed in the oocyte nuclei of stage II follicles, however, UIIR was found in the follicle cells and oocyte cytoplasm of stage II and stage III follicles. Similarly, immunohistochemistry found positive signal of UII was detected in the oocyte nuclei of stage II follicles. The results from in vitro culture of olive flounder follicles suggested the expression of UII and UIIR mRNA levels significantly increased by 10 IU/ml human chorionic gonadotropin (hCG) for 9 h. Furthermore, the transcriptional expression of UII and UIIR was not statistically significantly changed by 17α, 20β-dihydroxy-4-pregnen-3-one (DHP). These results firstly suggested that UII and UII receptor may play vital roles in regulating ovarian growth in olive flounder. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Granulocyte-colony stimulating factor (G-CSF) is used routinely in clinical practice for the treatment of neutropenia and to increase generation of hematopoietic stem cells in bone marrow donors. A growing body of literature on the neurotrophic effects of G-CSF has led to clinical trials in stroke, Alzheimer''s disease (AD) and Parkinson''s disease (PD). Objectives: The primary objective of this study was to determine if G-CSF administration would rescue the nigro-striatal system and restore locomotor function after completion of a sub-acute course of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration (30mg/kg i.p. for 5 days) in 12 month-old mice. A secondary aim was to determine if G-CSF affects the neuro-inflammatory response by modulating microglial activation in striatum and midbrain. Results: MPTP-treated mice were impaired on the rotometer test after the last dose of the toxicant and remained impaired until euthanasia. MPTP-treated mice that were given an 8-day regimen of G-CSF starting 2 days after the last dose of toxicant enhanced motor performance compared to the MPTP alone group. MPTP treatment depleted striatal DA (DA) levels; G-CSF given after MPTP resulted in a partial, significant repletion of DA levels. Total microglial burden in the striatum was increased significantly in MPTP-treated mice and was reduced after G-CSF rescue. Conclusion: G-CSF enhances recovery of DA nigro-striatal function from MPTP toxicity in part by modulating the microglial response to injury. The G-CSF receptor may provide a novel target for modifying the disease process in Parkinson''s disease. [Copyright &y& Elsevier]

With the development of display systems, artificial lighting, and fluorescent sensor, white light emission (WLE) materials have received great attention in recent years. Various organic and inorganic compounds have been synthesized to generate WLE. Natural products with WLE ability are attractive for their easy availability and cost effective. However, WLE from natural products are very rare and mainly realized by a complicated combination of two or three natural dyes emitting complementary lights. A single natural product molecule that can generate WLE has not yet been reported. Camptothecin (CPT) and its derivative 10-hydroxycamptothecin (HCPT) are natural products with anti-tumour activity and unique fluorescence properties. Here we demonstrated that CPT showed pH-dependent WLE properties. CPT can produce WLE in an acetic acid-ethanol mixture with 35% acetic acid fraction (V/V) under excitation at 360 nm. HCPT showed solvatochromism-dependent WLE properties and can easily generate WLE by adjusting the ratios of water/ethanol solution and showed an extremely close pure white fluorescence in a water-ethanol mixture with 5.7% water fraction (V/V). The corresponding Commission Internationale d'Eclairage (CIE) coordinates is (0.32, 0.34). Due to the remarkable excited-state acidity properties, the WLE efficiency of HCPT was extraordinarily high with a 31.72% quantum yield. HCPT also can produce WLE in triethylamine-ethanol solution and showed great CIE coordinates (0.31, 0.34) in 9.1% triethylamine fraction (V/V). Besides, we performed preliminary white fluorescent application of HCPT in polyvinyl alcohol films with good results. The WLE mechanisms of CPT and HCPT were also discussed. We hope our findings could inspire more WLE studies about CPT and its derivatives. Meanwhile, more single natural molecules with WLE properties could be discovered. Image 1 • Two single natural molecules that can generate white light emission were reported. • CPT and HCPT generate white light emission easily by adjusting the ratio of solvents. • HCPT showed solvatochromism-depend WLE in water-ethanol mixture with CIE (0.32, 0.34). [ABSTRACT FROM AUTHOR]