A potentially general and green approach based on Claisen condensation that enabled low-migrating aliphatic ester-derived PVC plasticizers as sustainable alternatives to DEHP was reported.

The paper assesses sex-age-specific mortality rates of the four groups of people in China, the country, cities, towns, and counties, based on the mortality data from the China Population Statistics Yearbooks (1988Á2009) using a newly proposed modified LeeÁCarter model. The results show that in general, the expected age-specific mortality rates decrease over the years, and the decreasing speed increased in the past decade. During 2000Á2008, the expected mortality rates decreased over the years for females of all ages and groups and males in cities, remained with no changes for males ages 13Á36 in the country and towns, but increased for males ages 13Á43 in counties. Predictions for 2009 are made based on the 2000Á2008 data, and comparisons to the observed rates from an annual survey show that they match each other well except for males ages 13Á43 in counties, whose mortality rates reached record highs around 2005, and bounced back to the level of 2000 in 2008 and was reduced a little further in 2009, benefiting from the promulgations and enforcements of some safety regulations by the government on construction and mining sites where most labors are from counties. The predicted age-specific mortality rates from the model are compared to the assumed rates in the China Life Insurance Mortality Table (2000Á2003) promulgated by the China Insurance Regulatory Commission, and they show a great deal of similarity in terms of changing trends over the ages.

No abstract

A light-responsive, non-persistent 2D supramolecular polymer sheet with a potentially diminished environmental impact was reported.

Processing polyvinyl chloride (PVC) artificial material requires plasticizer that softens the PVC coating. Currently, utilizing unsaturated fatty acid methyl esters to obtain epoxidized fatty acid methyl ester (EFAME) bio-plasticizers constitutes an environmentally responsible solution to substitute conventional ortho-phthalates that are endocrine disruptors or probable carcinogens. However, commercial EFAMEs, even with the highest epoxy value (ca. 5.5-5.8%) so far, still suffer from fast leaching from the PVC matrix, burdening the environment and shortening lifespan of the artificial material. Here, we report a proof-of-principle demonstration of a new strategy to obtain migration-resistant EFAME that harnesses the midchain hydroxyl of methyl ricinoleate and covalently attachment of a pendant acetate ester. Despite a low epoxy value (3.0%), the engineered bio-plasticizer displays significantly suppressed migration in multiple scenarios compared with one conventional EFAME with much higher epoxy value (5.8%). Circumventing the limit confronting previous strategy that highlights the sole contribution of epoxy value to achievable migration resistance, the rationale herein may provide guidance for designing new EFAMEs with comparable performance to ortho-phthalates, thus bringing the old and oft-maligned PVC artificial material industry one step closer to sustainability.

some 2D materials translocate into living cells via endocytosis, offering a promising platform that enables intracellular bioimaging, [1][2][3] biosensing, [4][5][6] or disease theranostics. [7][8][9][10] Despite encouraging advances in this emerging field, one major challenge lies in managing the trade-off between lateral size of the 2D platform and their cellular uptake. In general, 2D materials with a small lateral dimension are easily taken up by cells but clear fast. One typical example [11] is doxorubicinloaded 2D molybdenum disulfide (MoS 2 ) nanosheets recently reported for synergistic chemo-photothermal cancer therapy. The drug-loaded MoS 2 platform, due to its small lateral size (≈116 nm), could be well internalized by cancer cells, but suffered from exocytosis that compromised the therapeutic effect unless exocytosis inhibitor was added. In comparison, large 2D materials have longer retention time in cells, thus affording greater potency to serve as intracellular functional platforms than small counterparts of the same composition. However, an ultrahigh-aspect-ratio makes the endocytosis of very large 2D materials extremely difficult. [12,13] Having this dilemma in mind, previous researchers had to employ relatively small 2D materials (lateral dimension < 200 nm) as intracellular signaling or theranostic platforms, [2][3][4][5][6][7][8][9][10][11] simply because they were readily endocytosable compared with micrometer-sized counterparts, even though the latter were conceivably more qualifying candidates.Indeed, 2D materials, regardless of chemical composition, can invariably be regarded as an assembly composed of laterally connected areal monomeric units that extend in two orthogonal directions. [14,15] These monomers are typically less than 1 nm in size, thus having no trouble being internalized and enriched inside living cells. Bearing this in mind, we envision unprecedentedly large 2D materials can be directly generated in cell milieu provided that the internalized monomers in situ polymerize efficiently with the inter-monomer connections being strictly confined to lateral directions. As such, the otherwise non-endocytosable large 2D materials can eventually enter the cells, addressing the lateral size versus cellular uptake trade-off aforementioned.An areal monomeric unit designed for such a purpose then must meet several demanding requirements: 1) it should be The unique structural advantage and physicochemical properties render some 2D materials emerging platforms for intracellular bioimaging, biosensing, or disease theranostics. Despite recent advances in this field, one major challenge lies in bypassing the endocytic uptake barrier to allow internalization of very large 2D materials that have longer retention time in cells, and hence greater potency as intracellular functional platforms than small, endocytosable counterparts. Here, an engineered cucurbit[6]uril carrying at its periphery multiple spiropyran pendants that readily translocates into cytosol, and then polymerizes laterally and non-c...

No abstract

Purpose: A novel deep learning model, Siamese Ensemble Boundary Network (SEB-Net) was developed to improve the accuracy of automatic organs-at-risk (OARs) segmentation in CT images for head and neck (HaN) as well as small organs, which was verified for use in radiation oncology practice and is therefore proposed.Methods: SEB-Net was designed to transfer CT slices into probability maps for the HaN OARs segmentation purpose. Dual key contributions were made to the network design to improve the accuracy and reliability of automatic segmentation toward the specific organs (e.g., relatively tiny or irregularly shaped) without sacrificing the field of view. The first implements an ensemble of learning strategies with shared weights that aggregates the pixel-probability transfer at three orthogonal CT planes to ameliorate 3D information integrity; the second exploits the boundary loss that takes the form of a distance metric on the space of contours to mitigate the challenges of conventional region-based regularization, when applied to highly unbalanced segmentation scenarios. By combining the two techniques, enhanced segmentation could be expected by comprehensively maximizing inter- and intra-CT slice information. In total, 188 patients with HaN cancer were included in the study, of which 133 patients were randomly selected for training and 55 for validation. An additional 50 untreated cases were used for clinical evaluation.Results: With the proposed method, the average volumetric Dice similarity coefficient (DSC) of HaN OARs (and small organs) was 0.871 (0.900), which was significantly higher than the results from Ua-Net, Anatomy-Net, and SRM by 4.94% (26.05%), 7.80% (24.65%), and 12.97% (40.19%), respectively. By contrast, the average 95% Hausdorff distance (95% HD) of HaN OARs (and small organs) was 2.87 mm (0.81 mm), which improves the other three methods by 50.94% (75.45%), 88.41% (79.07%), and 5.59% (67.98%), respectively. After delineation by SEB-Net, 81.92% of all organs in 50 HaN cancer untreated cases did not require modification for clinical evaluation.Conclusions: In comparison to several cutting-edge methods, including Ua-Net, Anatomy-Net, and SRM, the proposed method is capable of substantially improving segmentation accuracy for HaN and small organs from CT imaging in terms of efficiency, feasibility, and applicability.