Effective Morphology Control in an Immiscible Crystalline/Crystalline Blend by Artificially Selected Viscoelastic Phase Separation Pathways

We investigated the interplay between viscoelastic phase separation (VPS) and crystallization in a dynamically asymmetric crystalline/crystalline polymer blend system of poly­(butylene succinate) (PBS)/poly­(ethylene oxide) (PEO). The dynamic asymmetry came from the large molecular weight difference between the slow relaxing PEO and the fast relaxing PBS molecules. The evolution of network-like structures, phase inversion, and volume shrinking processes were studied by a phase contrast microscope (PCOM). The crystallization kinetics of PBS was determined by a differential scanning calorimeter (DSC). It was found that both the crystal nucleation and growth of PBS were strongly influenced by the existence and relaxation of the entangled PEO network, even though PEO was the minor component. The nuclei of PBS were more inclined to form at the interface between phase domains due to the effect of interface-assisted crystallization. Thus, the nucleation density decreased with the decrease of interfacial area. Meanwhile, the corresponding crystal growth rate was also dependent on the VPS processes. After a second quench to a temperature below the melting point of PEO, the spatial distribution of both components and the final crystallization morphology were also significantly controlled by the initial phase structures. Compared to dynamically symmetric polymer systems, the VPS process provided more versatile pathways to control the phase and crystallization morphologies in such immiscible crystalline/crystalline polymer blends

Dually Actuated Triple Shape Memory Polymers of Cross-Linked Polycyclooctene–Carbon Nanotube/Polyethylene Nanocomposites

In this work, electrically and thermally actuated triple shape memory polymers (SMPs) of chemically cross-linked polycyclooctene (PCO)–multiwalled carbon nanotube (MWCNT)/polyethylene (PE) nanocomposites with co-continuous structure and selective distribution of fillers in PCO phase are prepared. We systematically studied not only the microstructure including morphology and fillers’ selective distribution in one phase of the PCO/PE blends, but also the macroscopic properties including thermal, mechanical, and electrical properties. The co-continuous window of the immiscible PCO/PE blends is found to be the volume fraction of PCO (<i>v</i>^PCO) of ca. 40–70 vol %. The selective distribution of fillers in one phase of co-continuous blends is obtained by a masterbatch technique. The prepared triple SMP materials show pronounced triple shape memory effects (SMEs) on the dynamic mechanical thermal analysis (DMTA) and the visual observation by both thermal and electric actuations. Such polyolefin samples with well-defined microstructure, electrical actuation, and triple SMEs might have potential applications as, for example, multiple autochoke elements for engines, self-adjusting orthodontic wires, and ophthalmic devices

T cell subsets and immunoglobulin G levels are associated with the infection status of systemic lupus erythematosus patients

<div><p>Systemic lupus erythematosus (SLE) is a chronic, autoimmune disorder that affects nearly all organs and tissues. As knowledge about the mechanism of SLE has increased, some immunosuppressive agents have become routinely used in clinical care, and infections have become one of the direct causes of mortality in SLE patients. To identify the risk factors indicative of infection in SLE patients, a case control study of our hospital's medical records between 2011 and 2013 was performed. We reviewed the records of 117 SLE patients with infection and 61 SLE patients without infection. Changes in the levels of T cell subsets, immunoglobulin G (IgG), complement C3, complement C4, globulin, and anti-double-stranded DNA (anti-ds-DNA) were detected. CD4+ and CD4+/CD8+ T cell levels were significantly lower and CD8+ T cell levels were significantly greater in SLE patients with infection than in SLE patients without infection. Additionally, the concentrations of IgG in SLE patients with infection were significantly lower than those in SLE patients without infection. However, complement C3, complement C4, globulin, and anti-ds-DNA levels were not significantly different in SLE patients with and without infection. Therefore, clinical testing for T cell subsets and IgG is potentially useful for identifying the presence of infection in SLE patients and for distinguishing a lupus flare from an acute infection.</p></div

DataSheet1_Direct preparation of solid carbon dots by pyrolysis of collagen waste and their applications in fluorescent sensing and imaging.DOCX

The fluorescent carbon dots (CDs) have found their extensive applications in sensing, bioimaging, and photoelectronic devices. In general terms, the synthesis of CDs is straight-forward, though their subsequent purification can be laborious. Therefore, there is a need for easier ways to generate solid CDs with a high conversion yield. Herein, we used collagen waste as a carbon source in producing solid CDs through a calcination procedure without additional chemical decomposition treatment of the raw material. Considering a mass of acid has destroyed the original protein macromolecules into the assembled structure with amino acids and peptide chains in the commercial extraction procedure of collagen product. The residual tissues were assembled with weak intermolecular interactions, which would easily undergo dehydration, polymerization, and carbonization during the heat treatment to produce solid CDs directly. The calcination parameters were surveyed to give the highest conversion yield at 78%, which occurred at 300°C for 2 h. N and S atomic doping CDs (N-CDs and S-CDs) were synthesized at a similar process except for immersion of the collagen waste in sulfuric acid or nitric acid in advance. Further experiments suggested the prepared CDs can serve as an excellent sensor platform for Fe3+ in an acid medium with high anti-interference. The cytotoxicity assays confirmed the biosafety and biocompatibility of the CDs, suggesting potential applications in bioimaging. This work provides a new avenue for preparing solid CDs with high conversion yield.</p