Multifunctional Inverted Nanocone Arrays for Non‐Wetting,Self‐Cleaning Transparent Surface with High Mechanical Robustness

A multifunctional surface that enables control of wetting, optical reflectivity and mechanical damage of nanostructured interfaces is presented. Our approach is based on imprinting a periodic array of nanosized cones into a UV‐curable polyurethane acrylate (PUA), resulting in a self‐reinforcing egg‐crate topography evenly distributed over large areas up to several cm² in size. The resulting surfaces can be either superhydrophilic or superhydrophobic (through subsequent application of an appropriate chemical coating), they minimize optical reflection losses over a broad range of wavelengths and a wide range of angles of incidence, and they also have enhanced mechanical resilience due to greatly improved redistribution of the normal and shearing mechanical loads. The transmissivity and wetting characteristics of the nanoscale egg‐crate structure, as well as its resistance to mechanical deformation are analyzed theoretically. Experiments show that the optical performance together with self‐cleaning or anti‐fogging behavior of the inverted nanocone topography is comparable to earlier designs that have used periodic arrays of nanocones to control reflection and wetting. However the egg‐crate structures are far superior in terms of mechanical robustness, and the ability to replicate this topography through several generations is promising for large‐scale commercial applications where multifunctionality is important.     

甘蔗收购体制(续)

(上接本刊2005年第6期) 提高甘蔗质量和糖分收回的鼓励制度 表Ⅱ表示不同国家的甘蔗收购体制因甘蔗质量和糖厂效率提高而回报蔗农和糖厂(作为一个集团)的程度.这个表给出由糖分含量增加10%而引起蔗农收入的百分数变化的估计,同时列出了表示糖厂糖分收回增加10%的影响引起的相应百分数变化数字.     

Fate of higher brominated PBDEs in lactating cows

Dietary intake studies of lower brominated diphenyl ethers (BDEs) have shown that fish and animal products are important vectors of human exposure, but almost no data exist for higher brominated BDEs. Therefore, the fate of hepta- to decaBDEs was studied in lactating cows exposed to a naturally contaminated diet by analyzing feed, feces, and milk samples from a previous mass balance study of PCB. Tissue distribution was studied in one cow slaughtered after the experiment. BDE-209 was the dominant congener in feed, organs, adipose tissues, and feces, but not in milk. In contrast to PCBs and lower brominated BDEs, concentrations of hepta- to decaBDEs in adipose tissue were 9-80 times higher than in milk fat and the difference increased with degree of bromination/log K(OW). The congener profiles in adipose tissue and feed differed; BDE-207, BDE-196, BDE-197, and BDE-182 accumulated to a surprisingly greater extent in the fat compared to their isomers, suggesting metabolic debromination of BDE-209 to these BDEs. The results indicate that meat rather than dairy product consumption may be an important human exposure route to higher brominated BDEs.     

Geomicrobiological redox cycling of the transuranic element neptunium

Microbial processes can affect the environmental behavior of redox sensitive radionuclides, and understanding these reactions is essential for the safe management of radioactive wastes. Neptunium, an alpha-emitting transuranic element, is of particular importance because of its long half-life, high radiotoxicity, and relatively high solubility as Np(V)O(2)(+) under oxic conditions. Here, we describe experiments to explore the biogeochemistry of Np where Np(V) was added to oxic sediment microcosms with indigenous microorganisms and anaerobically incubated. Enhanced Np removal to sediments occurred during microbially mediated metal reduction, and X-ray absorption spectroscopy showed this was due to reduction to poorly soluble Np(IV) on solids. In subsequent reoxidation experiments, sediment-associated Np(IV) was somewhat resistant to oxidative remobilization. These results demonstrate the influence of microbial processes on Np solubility and highlight the critical importance of radionuclide biogeochemistry in nuclear legacy management.     

Biodistribution and Cellular Internalization of Inactivated SARS-CoV-2 in Wild-Type Mice

Despite the growing list of identified SARS-CoV-2 receptors, the human angiotensin-converting enzyme 2 (ACE2) is still viewed as the main cell entry receptor mediating SARS-CoV-2 internalization. It has been reported that wild-type mice, like other rodent species of the Muridae family, cannot be infected with SARS-CoV-2 due to differences in their ACE2 receptors. On the other hand, the consensus heparin-binding motif of SARS-CoV-2’s spike protein, PRRAR, enables the attachment to rodent heparan sulfate proteoglycans (HSPGs), including syndecans, a transmembrane HSPG family with a well-established role in clathrin- and caveolin-independent endocytosis. As mammalian syndecans possess a relatively conserved structure, we analyzed the cellular uptake of inactivated SARS-CoV-2 particles in in vitro and in vivo mice models. Cellular studies revealed efficient uptake into murine cell lines with established syndecan-4 expression. After intravenous administration, inactivated SARS-CoV-2 was taken up by several organs in vivo and could also be detected in the brain. Internalized by various tissues, inactivated SARS-CoV-2 raised tissue TNF-α levels, especially in the heart, reflecting the onset of inflammation. Our studies on in vitro and in vivo mice models thus shed light on unknown details of SARS-CoV-2 internalization and help broaden the understanding of the molecular interactions of SARS-CoV-2.     

11β-Hydroxysteroid Dehydrogenase Type 1 within Osteoclasts Mediates the Bone Protective Properties of Therapeutic Corticosteroids in Chronic Inflammation

Therapeutic glucocorticoids (GCs) are powerful anti-inflammatory tools in the management of chronic inflammatory diseases such as rheumatoid arthritis (RA). However, their actions on bone in this context are complex. The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is a mediator of the anti-inflammatory actions of therapeutic glucocorticoids (GCs) in vivo. In this study we delineate the role of 11β-HSD1 in the effects of GC on bone during inflammatory polyarthritis. Its function was assessed in bone biopsies from patients with RA and osteoarthritis, and in primary osteoblasts and osteoclasts. Bone metabolism was assessed in the TNF-tg model of polyarthritis treated with oral GC (corticosterone), in animals with global (TNF-tg^11βKO), mesenchymal (including osteoblast) (TNF-tg^{11βflx/tw2cre}) and myeloid (including osteoclast) (TNF-tg^{11βflx/LysMcre}) deletion. Bone parameters were assessed by micro-CT, static histomorphometry and serum metabolism markers. We observed a marked increase in 11β-HSD1 activity in bone in RA relative to osteoarthritis bone, whilst the pro-inflammatory cytokine TNFα upregulated 11β-HSD1 within osteoblasts and osteoclasts. In osteoclasts, 11β-HSD1 mediated the suppression of bone resorption by GCs. Whilst corticosterone prevented the inflammatory loss of trabecular bone in TNF-tg animals, counterparts with global deletion of 11β-HSD1 were resistant to these protective actions, characterised by increased osteoclastic bone resorption. Targeted deletion of 11β-HSD1 within osteoclasts and myeloid derived cells partially reproduced the GC resistant phenotype. These data reveal the critical role of 11β-HSD1 within bone and osteoclasts in mediating the suppression of inflammatory bone loss in response to therapeutic GCs in chronic inflammatory disease.     

5G将从哪些方面提升新零售体验

5G技术的出现开启了一个互联和体验的全新时代,有可能会改变零售业的面貌.它支持的一系列进步应当可以缓解零售商在新冠肺炎疫情期间所面临的许多挑战.通过大幅提升移动网络的速度,5G技术为一系列令人眼花缭乱的创新铺平了道路.     

Nanoscale Disorder and Deintercalation Evolution in K-Doped MoS2 Analysed Via In Situ TEM

Intercalation and deintercalation processes in van der Waals crystals underpin their use in nanoelectronics, energy storage, and catalysis but there remains significant uncertainty regarding these materials’ structural and chemical heterogeneity at the nanoscale. Deintercalation in particular often controls the robustness and cyclability of the involved processes. Here, a detailed analysis of potassium ordering and compositional variations in as-synthesised K intercalated MoS₂ as well an analysis of deintercalation induced changes in the structure and K/Mo elemental composition is presented. By combining 4D scanning transmission electron microscopy (4DSTEM), in situ atomic resolution STEM imaging, selected area electron diffraction (SAED) and energy dispersive X-ray spectroscopy (EDS) the formation of previously unknown intermediate superstructures during deintercalation is revealed. The results provide evidence supporting a new deintercalation mechanism that favors formation of local regions with thermodynamically stable ordering rather than isotropic release of K. Systematic time-temperature measurements demonstrate the deintercalation behavior to follow first-order kinetics, allowing compositional and superstructural changes to be predicted. It is expected that the in situ correlative STEM-EDS/SAED methodology developed in this work has the potential to determine optimal synthesis, processing and working conditions for a variety of intercalated or pillared materials.     

Testing a novel sonar-based approach for measuring water depth and monitoring sediment storage in beaver ponds

Widely available ‘fish-finder’ echo-sounding devices are beginning to be used in bathymetric studies to estimate geomorphic change. To date, however, there have been no applications in shallow and complex wetlands, where changes in sediment storage are notoriously dynamic in time and difficult to describe accurately in space. Therefore, in this study, we tested the performance of an ‘off-the-shelf’ fish-finder for mapping bathymetry in a shallow beaver pond. We tested fish-finder sonar depth readings against a traditional-sounding lead-line method across 21 paired Sampling Points with a minimum depth of 0.31 m and a mean of 0.65 m. Spatial accuracy of the unit was also tested against a differentially corrected Global Navigation Satellite System (GNSS) receiver. Measured depths to pond bottom from the fish-finder were on average within 5%, although significantly 0.015 m (SD = 0.034) less than those obtained by the lead-line method. Spatial accuracy, however, varied greatly compared to the corrected GNSS receiver readings, with a mean discrepancy of 2.7 m (SD = 1.5) but up to 6.2 m. Given the close match of depth readings between the two methods, we conclude that sonar is a suitable, cost-effective, and less-intrusive method than existing techniques, even in moderately vegetated shallow waterbodies. Methods do need to be adopted to account for poor spatial precision with ‘off-the-shelf’ fish-finder models, but this can be rectified with survey design or using a secondary GNSS. Application of this technology will allow rapid one-off surveys or repeated monitoring of depth, bedform and sediment accumulation in otherwise hard-to-access or disturbance-sensitive wetlands, such as beaver ponds and water treatment or flow attenuation wetlands.