Plastic packaging materials are widely used because of their advantages of light weight, low cost, and convenience, especially as victuals packaging materials. Approximately 146 million metric tons ...of plastics were used for packaging in 2015, but most of these plastics had already been discarded and followed by serious white pollution. What's worse, the victuals packaging materials, especially polystyrene (PS) foam containers, can release microplastics (MPs) during daily usage. Through the combination of various appropriate chemical (eg, spectroscopy) and physical (eg, microscopy) characterization and analysis, the existence of MPs is proved and MPs can be intuitively observed. Although the impacts of MPs on ecosystems and human health are still under discussion, existing studies have shown that MPs can be integrated into habitats through soil transportation, affecting the health of various terrestrial invertebrates. Faced with this shocking reality, reducing the use of PS foam containers at high temperatures and developing healthy materials to substitute these plastics are promising solutions.
Based on the various appropriate chemical (e.g., spectroscopy) and physical (e.g., microscope) characterization and analysis, this paper provides sufficient evidence for the fact that the victuals packaging materials, especially polystyrene foam containers, can release microplastics (MPs) during daily usage. MPs have various sizes and irregularly shapes, which have potential threats to the ecosystems and human health.
We fabricated the HfZrO 2 (HZO) ferroelectric fin field-effect transistors (Fe-FinFET) with fin width of 60 nm and gate length of 100 nm for ferroelectric nonvolatile memory operations. The ...fabricated Fe-FinFET exhibited a large memory window (MW) of 1.5 V and high (100 ns) program/erase speeds at ±5 V. After <inline-formula> <tex-math notation="LaTeX">10^{{5}} </tex-math></inline-formula> program/erase cycles, the MW was maintained at 1.09 V and the retention time was measured up to <inline-formula> <tex-math notation="LaTeX">10^{{4}} </tex-math></inline-formula> s with no degradation. The fabricated HZO Fe-FinFET is compatible with the current FinFET process and has a high MW, a fast program/erase speed, and excellent reliability. Therefore, the fabricated Fe-FinFET is a promising candidate for high-density ferroelectric field-effect transistor memory applications.
Quantum key distribution (QKD) provides a promising solution for sharing information-theoretic secure keys between remote peers with physics-based protocols. According to the law of quantum physics, ...the photons carrying signals cannot be amplified or relayed via classical optical techniques to maintain quantum security. As a result, the transmission loss of the channel limits its achievable distance, and this has been a huge barrier towards building large-scale quantum-secure networks. Here we present an experimental QKD system that could tolerate a channel loss beyond 140 dB and obtain a secure distance of 833.8 km, setting a new record for fibre-based QKD. Furthermore, the optimized four-phase twin-field protocol and high-quality set-up make its secure key rate more than two orders of magnitude greater than previous records over similar distances. Our results mark a breakthrough towards building reliable and efficient terrestrial quantum-secure networks over a scale of 1,000 km.Twin-field (TF) quantum key distribution (QKD) over a secure distance of 833.8 km is demonstrated even in the finite-size regime. To this end, an optimized four-phase TF-QKD protocol and a high-speed low-noise TF-QKD system are developed.
With the development of the Internet of energy, more and more participants share data by different types of edge devices. However, such multi-source heterogenous data typically contain low-quality ...data, e.g., missing values, which may result in potential risks. Besides, resource-constrained devices incur large latency in edge computing networks. To alleviate such latency, distributed task offloading schemes are designed to share the computation burden between edge nodes and nearby servers. However, there are three main drawbacks of such schemes. First, low-quality data are not carefully evaluated by constraints under scenarios, which may result in slow convergence in distributed computation. Second, multi-source data including sensitive information are computed and shared among edge nodes without privacy protection. Third, distributed tasks on low-quality data may result in low-quality results even with an optimal offloading scheme. To address the problems above, a task offloading framework for edge computing based on consortium blockchain and distributed reinforcement learning is proposed in this paper, which can provide high-quality task offloading policies with data privacy protected. This framework consists of three key components: data quality evaluation (DQ) with multiple data quality dimensions, data repairing (DR) with a repairing algorithm based on a novel repairing consensus mechanism and distributed reinforcement learning for task arrangement (DELTA) with a distributed reinforcement learning algorithm based on a novel low-quality data distributing strategy. Numeric results are presented to illustrate the effectiveness and efficiency of the proposed task offloading framework for edge computing on low-quality data in the IoE.
Hydrogel materials with high water content and good biocompatibility are drawing more and more attention now, especially for biomedical use. However, it still remains a challenge to construct ...hydrogel fibers with enough strength and toughness for practical applications. Herein, we report a bio-inspired lotus-fiber-mimetic spiral structure hydrogel bacterial cellulose fiber with high strength, high toughness, high stretchability, and energy dissipation, named biomimetic hydrogel fiber (BHF). The spiral-like structure endows BHF with excellent stretchability through plastic deformation and local failure, assisted by the breaking–reforming nature of the hydrogen bonding network among cellulose nanofibers. With the high strength, high stretchability, high energy dissipation, high hydrophilicity, porous structure, and excellent biocompatibility, BHF is a promising hydrogel fiber for biomedicine. The outstanding stretchability and energy dissipation of BHF allow it to absorb energy from the tissue deformation around a wound and effectively protect the wound from rupture, which makes BHF an ideal surgical suture.
Hydrogel materials have many excellent properties and a wide range of applications. Recently, a new type of hydrogel has emerged: cellulose nanofiber (CNF)-based hydrogels, which have ...three-dimensional nanofiber networks and unique physical properties. Because CNFs are abundant, renewable, and biodegradable, they are green and eco-friendly nanoscale building blocks. In addition, CNF-based hydrogel materials exhibit excellent mechanical properties and designable functions by different preparation methods and structure designs, demonstrating huge development potential. In this Perspective, we summarize the recent progress in the development of CNF-based hydrogels and introduce their applications in elastic hydrogels, ionic conduction, water purification, and biomedicine, highlighting future trends and opportunities for the further development of CNF-based hydrogels as emerging materials systems.
Pollution by heavy metals limits the area of land available for cultivation of food crops. A potential solution to this problem might lie in the molecular breeding of food crops for phytoremediation ...that accumulate toxic metals in straw while producing safe and nutritious grains. Here, we identify a rice quantitative trait locus we name cadmium (Cd) accumulation in leaf 1 (CAL1), which encodes a defensin-like protein. CAL1 is expressed preferentially in root exodermis and xylem parenchyma cells. We provide evidence that CAL1 acts by chelating Cd in the cytosol and facilitating Cd secretion to extracellular spaces, hence lowering cytosolic Cd concentration while driving long-distance Cd transport via xylem vessels. CAL1 does not appear to affect Cd accumulation in rice grains or the accumulation of other essential metals, thus providing an efficient molecular tool to breed dual-function rice varieties that produce safe grains while remediating paddy soils.
Background:
The complications of coronavirus disease 2019 (COVID-19) involved multiple organs or systems, especially in critically ill patients. We aim to investigate the neurological complications ...in critically ill patients with COVID-19.
Methods:
This retrospective single-center case series analyzed critically ill patients with COVID-19 at the intensive care unit of Tongji Hospital, Wuhan, China from February 5 to April 2, 2020. Demographic data, clinical and laboratory findings, comorbidities and treatments were collected and analyzed.
Results:
Among 86 patients with confirmed COVID-19, 54 patients (62.8%) were male, and the mean (SD) age was 66.6 (11.1) years. Overall, 65% patients presented with at least one neurological symptom. Twenty patients (23.3%) had symptoms involving the central nervous system, including delirium, cerebrovascular diseases and hypoxic-ischemic brain injury, while 6 patients (7%) had neuromuscular involvement. Seven of 86 patients exhibited new stroke and 6 (7%) cases were ischemic. A significantly higher prevalence of antiphospholipid antibodies was observed in patients with ischemic stroke than in those without stroke (83.3 vs. 26.9%,
p
< 0.05). Patients with ischemic stroke were more likely to have a higher myoglobulin level, and a lower hemoglobin level.
Conclusions:
The clinical spectrum of neurological complications in critically ill patients with COVID-19 was broad. Stroke, delirium and neuromuscular diseases are common neurological complications of COVID-19. Physicians should pay close attention to neurological complications in critically ill patients with COVID-19.
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