Stroke represents a severe medical condition that causes stroke survivors to suffer from long-term and even lifelong disability. Over the past several decades, a vast majority of stroke research ...targets neuroprotection in the acute phase, while little work has been done to enhance stroke recovery at the later stage. Through reviewing current understanding of brain plasticity, stroke pathology, and emerging preclinical and clinical restorative approaches, this review aims to provide new insights to advance the research field for stroke recovery. Lifelong brain plasticity offers the long-lasting possibility to repair a stroke-damaged brain. Stroke impairs the structural and functional integrity of entire brain networks; the restorative approaches containing multi-components have great potential to maximize stroke recovery by rebuilding and normalizing the stroke-disrupted entire brain networks and brain functioning. The restorative window for stroke recovery is much longer than previously thought. The optimal time for brain repair appears to be at later stage of stroke rather than the earlier stage. It is expected that these new insights will advance our understanding of stroke recovery and assist in developing the next generation of restorative approaches for enhancing brain repair after stroke.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Seeking new, highly effective thermoelectrics Xiao, Yu; Zhao, Li-Dong
Science (American Association for the Advancement of Science),
03/2020, Volume:
367, Issue:
6483
Journal Article
Peer reviewed
Operating across a wide temperature range is a priority for thermoelectric materials
Thermoelectric technology can directly and reversibly convert heat to electrical energy. Although thermoelectric ...energy conversion will never be as efficient as a steam engine (
1
), improving thermoelectric performance can potentially make a technology commercially competitive. Thermoelectric conversion efficiency is estimated by the so-called dimensionless figure of merit,
ZT = S
2
σ
T
/κ, where
S
, σ,
T
, and κ denote the Seebeck coefficient, electrical conductivity, working temperature, and thermal conductivity, respectfully . These parameters are strongly coupled, and improving the final
ZT
is challenging as a result. Strategies for boosting thermoelectric performance include nanostructuring, band engineering, nanomagnetic compositing, high-throughput screening, and others (
2
). Many of these strategies create a high
ZT
in a narrow range of temperatures, limiting the overall energy conversion. Finding materials with wider operating temperature ranges may require rethinking development strategies.
The thermoelectric (TE) efficiency is evaluated by the material thermoelectric figure of merit (ZT), which can be usually improved by enhancing the electrical transport properties and/or reducing the ...thermal conductivity. Seeking the material with low thermal conductivity is crucial for thermoelectrics, which enable us simplify complex thermoelectric parameters and focus on the optimization of electrical transport properties alone. Here, we summarized the relationship between anharmonicity and low thermal conductivity in thermoelectrics. Several strategies which yield anharmonicity are also suggested, including lone pair electron, resonant bonding and rattling model. At last, some intuitive methods were proposed and summarized to evaluate the anharmonicity.
Display omitted
•The low thermal conductivity is strictly related to anharmonicity.•The physical issues including lone pair electron, resonant bonding and rattling model yield anharmonicity.•The intuitive methods to evaluate the anharmonicity are proposed and summarized.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The growing demand of thermal management in various fields such as miniaturized 5G chips has motivated researchers to develop new and high-performance solid-state refrigeration technologies, ...typically including multicaloric and thermoelectric (TE) cooling. Among them, TE cooling has attracted huge attention owing to its advantages of rapid response, large cooling temperature difference, high stability, and tunable device size. Bi
2
Te
3
-based alloys have long been the only commercialized TE cooling materials, while novel systems SnSe and Mg
3
(Bi,Sb)
2
have recently been discovered as potential candidates. However, challenges and problems still require to be summarized and further resolved for realizing better cooling performance. In this review, we systematically investigate TE cooling from its internal mechanism, crucial parameters, to device design and applications. Furthermore, we summarize the current optimization strategies for existing TE cooling materials, and finally provide some personal prospects especially the material-planification concept on future research on establishing better TE cooling.
This review systematically elucidates the thermoelectric cooling technology, and proposes a strategy for boosting the power factor by improving carrier mobility through utilizing the material-planification concept.
An iridium(III)‐catalyzed three‐component reaction of enamides, aryldiazonium tetrafluoroborates, and 1,4‐diazabicyclo2.2.2octane bis(sulfur dioxide) (DABSO) for the direct C(sp2)−H arylsulfonylation ...of enamides is developed. This transformation provides a robust and straightforward approach for preparing a diverse array of β‐amidovinyl sulfones in moderate to excellent yields and high stereoselectivities without Light‐emitting diode (LED) radiation. This transformation also features mild conditions, broad substrate scopes, and excellent functional group tolerance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In a crisis, regulators and private investors can find it difficult, if not impossible, to tell whether banks facing runs are insolvent or merely illiquid. We introduce such an information constraint ...into a global-games-based bank run model with multiple banks and aggregate uncertainties. The information constraint creates a vicious cycle between contagious bank runs and falling asset prices and limits the effectiveness of traditional emergency liquidity assistance programs. We explain how a regulator can set up committed liquidity support to contain contagion and stabilize asset prices even without information on banks’ solvency, rationalizing some recent developments in policy practices.
This paper was accepted by Agostino Capponi, finance.
Funding:
This work was supported by the National Natural Science Foundation of China Project 71803024. Z. Li also acknowledges financial support from “Innovation and Talent Base for Digital Technology and Finance” of China Project B21038.
Supplemental Material:
The online appendix is available at
https://doi.org/10.1287/mnsc.2021.4258
.
Molecule‐based magnetic materials are useful candidates as the spin qubit due to their long coherence time and high designability. The anisotropy of the g‐values of the metal complexes can be ...utilized to access the individual spin of the metal complexes, making it possible to achieve the scalable molecular spin qubit. For this goal, it is important to evaluate the effect of g‐value anisotropy on the magnetic relaxation behaviour. This study reports the slow magnetic relaxation behaviour of chromium nitride (CrN2+) porphyrinato complex (1), which is structurally and magnetically similar with the vanadyl (VO2+) porphyrinato complex (2) which is known as the excellent spin qubit. Detailed analyses for vibrational and dynamical magnetism of 1 and 2 revealed that g‐value anisotropy accelerates magnetic relaxations greater than the internal magnetic field from nuclear spin does. These results provide a design criterion for construction of multiple spin qubit based on g‐tensor engineering.
Detailed analyses for vibrational and dynamical magnetism of chromium nitride (CrN2−)‐porphyrinato complex revealed that g‐value anisotropy accelerates magnetic relaxations greater than the internal magnetic field from nuclear spin does.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Infectious diseases are caused by pathogenic microorganisms and can be transmitted between individuals and populations thus threatening the general public health and potentially the economy. ...Efficient diagnostic tools are needed to provide accurate and timely guidance for case identification, transmission disruption and appropriate treatment administration. Point of care (POC) tests provide actionable results near the patient and thereby serve as a personal “radar”. In this review, we review clinical needs for POC testing for several major pathogens, including malaria parasites, human immunodeficiency virus (HIV), human papillomavirus (HPV), dengue, Ebola and Zika viruses and Mycobacterium tuberculosis (TB). We compare different molecular approaches, including pathogen nucleic acid and protein, circulating microRNA and antibodies, used in the POC tests. Finally, we review recent advances in novel POC technologies focusing on microfluidic and plasmonic-based approaches.
•POCT plays critical roles in diagnosis, treatment and prevention of infectious diseases.•Simple, accurate, multiplex and widely accessible POC tests are needed for many major pathogens.•POCT technologies have advanced significantly in the past decade, including microfluidics and plasmonics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Traumatic brain injury (TBI) presents in various forms ranging from mild alterations of consciousness to an unrelenting comatose state and death. In the most severe form of TBI, the entirety of the ...brain is affected by a diffuse type of injury and swelling. Treatment modalities vary extensively based on the severity of the injury and range from daily cognitive therapy sessions to radical surgery such as bilateral decompressive craniectomies. Guidelines have been set forth regarding the optimal management of TBI, but they must be taken in context of the situation and cannot be used in every individual circumstance. In this review article, we have summarized the current status of treatment for TBI in both clinical practice and basic research. We have put forth a brief overview of the various subtypes of traumatic injuries, optimal medical management, and both the noninvasive and invasive monitoring modalities, in addition to the surgical interventions necessary in particular instances. We have overviewed the main achievements in searching for therapeutic strategies of TBI in basic science. We have also discussed the future direction for developing TBI treatment from an experimental perspective.
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