Homochiral metal–organic framework (MOF) membranes have been recently reported for chiral separations. However, only a few high‐quality homochiral polycrystalline MOF membranes have been fabricated due to the difficulty in crystallization of a chiral MOF layer without defects on porous substrates. Alternatively, mixed matrix membranes (MMMs), which combine potential advantages of MOFs and polymers, have been widely demonstrated for gas separation and water purification. Here we report novel homochiral MOF–polymer MMMs for efficient chiral separation. Homochirality was successfully incorporated into achiral MIL‐53‐NH2 nanocrystals by post‐synthetic modification with amino acids, such as l‐histidine (l‐His) and l‐glutamic acid (l‐Glu). The MIL‐53‐NH‐l‐His and MIL‐53‐NH‐l‐Glu nanocrystals were then embedded into polyethersulfone (PES) matrix to form homochiral MMMs, which exhibited excellent enantioselectivity for racemic 1‐phenylethanol with the highest enantiomeric excess value up to 100 %. This work, as an example, demonstrates the feasibility of fabricating diverse large‐scale homochiral MOF‐based MMMs for chiral separation.

Interest in understanding the extent of plastic and specifically microplastic pollution has increased on a global scale. However, we still know relatively little about how much plastic pollution has found its way into the deeper areas of the world's oceans. The extent of microplastic pollution in deep-sea sediments remains poorly quantified, but this knowledge is imperative for predicting the distribution and potential impacts of global plastic pollution. To address this knowledge gap, we quantified microplastics in deepsea sediments from the Great Australian Bight using an adapted density separation and dye fluorescence technique. We analyzed sediment cores from six locations (1-6 cores each, n = 16 total samples) ranging in depth from 1,655 to 3,062 m and offshore distances ranging from 288 to 356 km from the Australian coastline. Microplastic counts ranged from 0 to 13.6 fragments per g dry sediment (mean 1.26 ± 0.68; n = 51). We found substantially higher microplastic counts than recorded in other analyses of deepsea sediments. Overall, the number of microplastic fragments in the sediment increased as surface plastic counts increased, and as the seafloor slope angle increased. However, microplastic counts were highly variable, with heterogeneity between sediment cores from the same location greater than the variation across sampling sites. Based on our empirical data, we conservatively estimate 14 million tonnes of microplastic reside on the ocean floor.

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Two independent biological replicates of estrogen depletion were employed with differing drug treatment conditions. Data Set I consisted of 9-month-old New Zealand white female rabbits treated as follows: sham-operated (n ¼ 11), ovariectomized (OVX; n ¼ 12), OVX þ 200 mg kg À 1 alendronate (ALN), 3 Â a week for 27 weeks (n ¼ 12) and OVX þ 10 mg kg À 1 Cathepsin-K inhibitor (CatKI) daily for 27 weeks. Data Set II consisted of 6-month-old New Zealand white female rabbits that were sham-operated (n ¼ 12), OVX (n ¼ 12) or OVX þ 0.05 mg kg À 1 17b-estradiol (ERT) 3 Â a week for 13 weeks (n ¼ 12). Samples from the cortical femur were polished and demineralized to make them suitable for atomic force microscopy (AFM) imaging. Type I collagen fibrils present in bundles or sheets, running parallel to each other, were combined into a class termed Parallel. Fibrils present outside of such structures, typically in images with an angular range of non-parallel fibrils, were combined into a class termed Oblique. The percentage of fibrils coded as Parallel for Sham animals in Data Sets I and II was 52% and 53%, respectively. The percentage of fibrils coded as Parallel for OVX animals in Data Sets I and II was 35% in both cases. ALN and ERT drug treatments reduced the change from 18 to 12%, whereas CatKI treatment reduced the change to 5%.