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MgtE is a Mg 2+-selective channel regulated by the intracellular Mg 2+ concentration. MgtE family proteins are highly conserved in all domains of life and contribute to cellular Mg 2+ homeostasis. In humans, mutations in the SLC41 proteins, the eukaryotic counterparts of the bacterial MgtE, are known to be associated with various diseases. The first MgtE structure from a thermophilic bacterium, Thermus thermophilus, revealed that MgtE forms a homodimer consisting of transmembrane and cytoplasmic domains with a plug helix connecting the two and that the cytoplasmic domain possesses multiple Mg 2+ binding sites. Structural and electrophysiological analyses revealed that the dissociation of Mg 2+ ions from the cytoplasmic domain induces structural changes in the cytoplasmic domain, leading to channel opening. Thus, previous works showed the importance of MgtE cytoplasmic Mg 2+ binding sites. Nevertheless, due to the limited structural information on MgtE from different species, the conservation and diversity of the cytoplasmic Mg 2+ binding site in MgtE family proteins remain unclear. Here, we report crystal structures of the Mg 2+-bound MgtE cytoplasmic domains from two different bacterial species, Chryseobacterium hispalense and Clostridiales bacterium, and identify multiple Mg 2+ binding sites, including ones that were not observed in the previous MgtE structure. These structures reveal the conservation and diversity of the cytoplasmic Mg 2+ binding site in the MgtE family proteins.

This study aims to establish a mechanistic model of using inherent safety and health concepts to conduct industrial workplace risk reduction strategies during the project planning stage. Accordingly, a dedicated implementation tool termed inherently safer and healthier design model for industrial workplaces (ISHDM‐IW) is developed. First, the safety and health by design checklist is adapted to derive industrial workplace safety and health risk indicators. Then, the risk indicators are rated and weighted using the methods of risk matrix and precedence chart. Subsequently, the risk indicators are aggregated via fuzzy risk representation with the indicators' risk values and weights. Last, the inherent safety and health principles are used to do risk‐based baseline design optimization. The case study demonstrates the capabilities of the proposed ISHDM‐IW to upgrade the workplace design scheme from risk level II to risk level I, thus generating a more satisfactory workplace design alternative. The proposed ISHDM‐IW offers a novel design mechanism of inherent safety and health for industrial workplaces, which can be expected to ensure employees' safety, health, and well‐being with fundamentally better ergonomics of industrial work environments. [ABSTRACT FROM AUTHOR]

Aim: Tyrosine decarboxylase (TDC) presented in the gut‐associated strain Enterococcus faecalis can convert levodopa (L‐dopa) into dopamine (DA), and its increased abundance would potentially minimize the availability and efficacy of L‐dopa. However, the known human decarboxylase inhibitors are ineffective in this bacteria‐mediated conversion. This study aims to investigate the inhibition of piperine (PIP) on L‐dopa bacterial metabolism and evaluates the synergistic effect of PIP combined with L‐dopa on Parkinson's disease (PD). Methods: Metagenomics sequencing was adopted to determine the regulation of PIP on rat intestinal microbiota structure, especially on the relative abundance of E. faecalis. Then, the inhibitory effects of PIP on L‐dopa conversion and TDC expression of E. faecalis were tested in vitro. We examined the synergetic effect of the combination of L‐dopa and PIP on 6‐hydroxydopamine (6‐OHDA)‐lesioned rats and tested the regulations of L‐dopa bioavailability and brain DA level by pharmacokinetics study and MALDI‐MS imaging. Finally, we evaluated the microbiota‐dependent improvement effect of PIP on L‐dopa availability using pseudo‐germ‐free and E. faecalis‐transplanted rats. Results: We found that PIP combined with L‐dopa could better ameliorate the move disorders of 6‐OHDA‐lesioned rats by remarkably improving L‐dopa availability and brain DA level than L‐dopa alone, which was associated with the effect of PIP on suppressing the bacterial decarboxylation of L‐dopa via effectively downregulating the abnormal high abundances of E. faecalis and TDC in 6‐OHDA‐lesioned rats. Conclusion: Oral administration of L‐dopa combined with PIP can improve L‐dopa availability and brain DA level in 6‐OHDA‐lesioned rats by suppressing intestinal bacterial TDC. [ABSTRACT FROM AUTHOR]

At present, deep learning has achieved excellent achievements in image processing and computer vision and is widely used in the field of watermarking. Attention mechanism, as the research hot spot of deep learning, has not yet been applied in the field of watermarking. In this paper, we propose a deep learning and attention network for robust image watermarking (DARI-Mark). The framework includes four parts: an attention network, a watermark embedding network, a watermark extraction network, and an attack layer. The attention network used in this paper is the channel and spatial attention network, which calculates attention weights along two dimensions, channel and spatial, respectively, assigns different weights to pixels in different channels at different positions and is applied in the watermark embedding and watermark extraction stages. Through end-to-end training, the attention network can locate nonsignificant areas that are insensitive to the human eye and assign greater weights during watermark embedding, and the watermark embedding network selects this region to embed the watermark and improve the imperceptibility. In watermark extraction, by setting the loss function, larger weights can be assigned to watermark-containing features and small weights to noisy signals, so that the watermark extraction network focuses on features about the watermark and suppresses noisy signals in the attacked image to improve robustness. To avoid the phenomenon of gradient disappearance or explosion when the network is deep, both the embedding network and the extraction network have added residual modules. Experiments show that DARI-Mark can embed the watermark without affecting human subjective perception and that it has good robustness. Compared with other state-of-the-art watermarking methods, the proposed framework is more robust to JPEG compression, sharpening, cropping, and noise attacks. [ABSTRACT FROM AUTHOR]

Inside sperm flagella, there are nine doublet microtubules composed of A and B tubules. In this issue of Cell , Leung et al. and Zhou et al. present high-resolution cryo-EM structures of doublet microtubules from mammalian sperms and show unprecedented structures of the A tubules, which are almost entirely occupied with tektin bundles. [ABSTRACT FROM AUTHOR]

Incineration has gradually become the most effective way to deal with MSW due to its obvious volume reduction and weight reduction effects. However, since heavy metals and organic pollutants carried by municipal solid waste incinerator fly ash (MSWI FA) pose a serious threat to the ecological environment and human health, they need to be handled carefully. In this study, the current status of MSWI FA disposal was first reviewed, and the harmless and resourceful disposal technologies of heavy metals and organic pollutants in MSWI FA are summarized as well. A summary of the advantages and disadvantages of each technology, including sintering, melting/vitrification, hydrothermal treatment, mechanochemistry, solidification/stabilization of MSWI FA, is compared. Finally, the research work that needs to be strengthened in the future (such as codisposal of multiple wastes, long-term stability research of disposal products, etc.) was proposed. Through comprehensive analysis, some reasonable and feasible suggestions were provided for the effective and safe disposal of MSWI FA in the future. [Display omitted] • The formation mechanism and degradation technology of PCDD/Fs are summarized. • The migration process and disposal technology of heavy metals of heavy metals are summarized. • The advantages, disadvantages and challenges of disposal technology are summarized. • The future research and development direction of MSWI FA disposal technology are discussed. • The direction for sustainable use of MSWI FA are provided. [ABSTRACT FROM AUTHOR]

As a new networking paradigm, opportunistic networking communications have great vision in animal migration tracking, mobile social networking, network communications in remote areas and intelligent transportation, and so on. Opportunistic networks are one of the evolutionary mobile ad hoc networks, whose communication links often suffer from frequent disruption and long communication delays. Therefore, many opportunistic forwarding protocols present major security issues, and the design of opportunistic networks faces serious challenges such as how to effectively protect data confidentiality and integrity and how to ensure routing security, privacy, cooperation, and trust management. In this paper, we first systematically describe the security threats and requirements in opportunistic networks; then propose a general security architecture of opportunistic networks; and then make an in-depth analysis on authentication and access control, secure routing, privacy protection, trust management, and incentive cooperation mechanisms; and at the same time, we present a comparison of various security and trust solutions for opportunistic networks. Finally, we conclude and give future research directions. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Shuiyindong Gold Mine hosts one of the largest and highest-grade, strata-bound Carlin-type gold deposits discovered to date in Southwestern China. The outcrop stratigraphy and drill core data of the deposit reveal Middle–Upper Permian and Lower Triassic formations. The ore is mainly hosted in Upper Permian bioclastic limestone near the axis of an anticline. The gold is mainly hosted in arsenian pyrite and arsenopyrite, mainly existing in the form of crystal lattice gold, submicroscopic particles and nanoparticles. Fluorite commonly occurs at the vicinity of an unconformity between the Middle–Upper Permian formations, which is proposed to be the structural conduit that fed the ore fluids. Calcite commonly fills fractures at the periphery of decarbonated rocks, which contain high grade orebodies. This study aimed to verify the occurrence of two distinct hydrothermal events at the Shuiyindong, based on Sm–Nd isotope dating of the fluorite and calcite. For this purpose, rare-earth element (REE) concentrations, Sm/Nd isotope ratios, and Sm–Nd isochron ages of the fluorite and calcite were determined. The fluorite and calcite contain relatively high total concentrations of REE (12.3–25.6 μg/g and 5.71–31.7 μg/g, respectively), exhibit variable Sm/Nd ratios (0.52–1.03 and 0.57–1.71, respectively), and yield Sm–Nd isochron ages of 200.1 ± 8.6 Ma and 150.2 ± 2.2 Ma, with slightly different initial ε Nd (t) values of −4.4 and −1.1, respectively. These two groups of Sm–Nd isochron ages suggest two episodes of hydrothermal events at the Shuiyindong gold deposit. The age of the calcite probably represents the late stage of the gold mineralization period. The initial ε Nd (t) values of the fluorite and calcite indicate that the Nd was probably derived from mixtures of basaltic volcanic tuff and bioclastic limestone from the Permian formations. [ABSTRACT FROM AUTHOR]

Expression of chloride channel 1 ( CLCN1/ClC-1 ) in skeletal muscle is driven by alternative splicing, a process regulated in part by RNA-binding protein families MBNL and CELF. Aberrant splicing of CLCN1 produces many mRNAs, which were translated into inactive proteins, resulting in myotonia in myotonic dystrophy (DM), a genetic disorder caused by the expansion of a CTG or CCTG repeat. This increase in abnormal splicing variants containing exons 6B, 7A or the insertion of a TAG stop codon just before exon 7 leads to a decrease in expression of the normal splice pattern. The majority of studies examining splicing in CLCN1 have been performed using mouse Clcn1 , as have investigations into the activation and suppression of normal splicing variant expression by MBNL1-3 and CELF3-6 , respectively. In contrast, examinations of human CLCN1 have been less common due to the greater complexity of splicing patterns. Here, we constructed a minigene containing CLCN1 exons 5-7 and established a novel assay system to quantify the expression of the normal splicing variant of CLCN1 using real-time RT-PCR. Antisense oligonucleotides could promote normal CLCN1 alternative splicing but the effective sequence was different from that of Clcn1 . This result differs from previous reports using Clcn1 , highlighting the effect of differences in splicing patterns between mice and humans.