Ischemic stroke caused by arterial occlusion is the most common type of stroke, which is among the most frequent causes of disability and death worldwide. Current treatment approaches involve ...achieving rapid reperfusion either pharmacologically or surgically, both of which are time‐sensitive; moreover, blood flow recanalization often causes ischemia/reperfusion injury. However, even though neuroprotective intervention is urgently needed in the event of stroke, the exact mechanisms of neuronal death during ischemic stroke are still unclear, and consequently, the capacity for drug development has remained limited. Multiple cell death pathways are implicated in the pathogenesis of ischemic stroke. Here, we have reviewed these potential neuronal death pathways, including intrinsic and extrinsic apoptosis, necroptosis, autophagy, ferroptosis, parthanatos, phagoptosis, and pyroptosis. We have also reviewed the latest results of pharmacological studies on ischemic stroke and summarized emerging drug targets with a focus on clinical trials. These observations may help to further understand the pathological events in ischemic stroke and bridge the gap between basic and translational research to reveal novel neuroprotective interventions.
A profound transformation of China's energy system is required to achieve carbon neutrality. Here, we couple Monte Carlo analysis with a bottom-up energy-environment-economy model to generate 3,000 ...cases with different carbon peak times, technological evolution pathways and cumulative carbon budgets. The results show that if emissions peak in 2025, the carbon neutrality goal calls for a 45-62% electrification rate, 47-78% renewable energy in primary energy supply, 5.2-7.9 TW of solar and wind power, 1.5-2.7 PWh of energy storage usage and 64-1,649 MtCO
of negative emissions, and synergistically reducing approximately 80% of local air pollutants compared to the present level in 2050. The emission peak time and cumulative carbon budget have significant impacts on the decarbonization pathways, technology choices, and transition costs. Early peaking reduces welfare losses and prevents overreliance on carbon removal technologies. Technology breakthroughs, production and consumption pattern changes, and policy enhancement are urgently required to achieve carbon neutrality.
The construction of active sites with intrinsic oxygen evolution reaction (OER) is of great significance to overcome the limited efficiency of abundant sustainable energy devices such as fuel cells, ...rechargeable metal–air batteries, and in water splitting. Anionic regulation of electrocatalysts by modulating the electronic structure of active sites significantly promotes OER performance. To prove the concept, NiFeS electrocatalysts are fabricated with gradual variation of atomic ratio of S:O. With the rise of S content, the overpotential for water oxidation exhibits a volcano plot under anionic regulation. The optimized NiFeS‐2 electrocatalyst under anionic regulation possesses the lowest OER overpotential of 286 mV at 10 mA cm−2 and the fastest kinetics being 56.3 mV dec−1 to date. The anionic regulation methodology not only serves as an effective strategy to construct superb OER electrocatalysts, but also enlightens a new point of view for the in‐depth understanding of electrocatalysis at the electronic and atomic level.
Anionic regulation of NiFe (oxy)sulfide electrocatalysts by modulating the electronic structure of oxygen evolution reaction (OER) active sites significantly promotes the water oxidation performance. Antagonistic S/O anions polarize the NiFe active sites, rendering the OER reactivity dependent on the anionic composition. The as‐obtained electrocatalyst exhibits superb OER performance with an ultralow overpotential of 286 mV at an OER current density of 10.0 mA cm−2.
This study assessed the number of individuals receiving treatment for opioid use disorder in the United States by age group and sex using a national prescription database to compare between the ...number of buprenorphine prescriptions filled and the number of US opioid-related overdose deaths.
Flexible and aqueous Zn–air batteries constitute promising next-generation energy storage devices to meet the growing demand for a safe and stable energy supply for flexible displays, wearable ...electronics, and implantable medical devices. However, their practical applications are severely hindered by the sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) at the air cathode. Herein, a porphyrin covalent organic framework (POF) was innovatively designed and applied as a cathode electrocatalyst for flexible Zn–air batteries. Porphyrin active sites were periodically constructed into well-defined two-dimensional (2D) frameworks precisely controlled at the atomic level, and carbon nanotubes (CNTs) served as scaffolds for further morphology regulation. Interwoven into a free-standing, robust, and flexible film, the as-fabricated CNT@POF hybrid demonstrates impressive performance in rechargeable liquid and flexible all-solid-state Zn–air batteries. Specifically, the liquid Zn–air battery with the CNT@POF cathode exhibits a small voltage gap of 0.71 V and outstanding stability for 200 cycles, even better than the noble-metal-based cathode. Flexible all-solid-state Zn–air batteries demonstrate a high energy efficiency of 61.6% at 1.0 mA cm −2 and the flexibility to stably light a red light-emitting diode (LED, 2.0 V) when bent to different degrees. This contribution demonstrates versatile and ingenious strategies for the multiscale regulation of advanced materials for energy electrocatalysis and thereby facilitates their applications in flexible and safe energy storage and conversion.
The cycling stability of lithium metal batteries is steadily improving. The safety issues, which mainly result from the employment of flammable solvents, should be strongly considered for practical ...Li metal batteries. Nonflammable solvents can mitigate fire hazards; however, their employment irreversibly deteriorates the cycling stability of working batteries owing to intrinsic high reactivity against Li metal. Herein, regulating solvation structure in a dimethylacetamide (DMAC)‐based electrolyte is proposed to achieve compatibility between cycling stability and nonflammability of electrolytes. DMAC, a nonflammable solvent, is employed to construct a nonflammable localized high‐concentration electrolyte (LHCE). In the DMAC‐based LHCE, there are abundant aggregate clusters resulting in the formation of anion‐derived solid electrolyte interphase to circumvent parasitic reactions between DMAC solvents and Li metal and to improve the uniformity of Li deposition, which ensures the compatibility between cycling stability under practical conditions and nonflammability of electrolytes. This work opens an emerging avenue to construct long‐cycling and safe Li metal batteries by manipulating solvation structure in nonflammable electrolytes.
Regulating solvation structure in a dimethylacetamide‐based nonflammable electrolyte is explored to achieve compatibility between cycling stability and safety of electrolytes for practical lithium metal batteries. In the localized high‐concentration electrolyte, aggregate clusters are generated and result in the formation of an anion‐derived solid electrolyte interphase, and also improve the uniformity of Li deposition.
Spin-neutral currents for spintronics Shao, Ding-Fu; Zhang, Shu-Hui; Li, Ming ...
Nature communications,
12/2021, Letnik:
12, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Electric currents carrying a net spin polarization are widely used in spintronics, whereas globally spin-neutral currents are expected to play no role in spin-dependent phenomena. Here we show that, ...in contrast to this common expectation, spin-independent conductance in compensated antiferromagnets and normal metals can be efficiently exploited in spintronics, provided their magnetic space group symmetry supports a non-spin-degenerate Fermi surface. Due to their momentum-dependent spin polarization, such antiferromagnets can be used as active elements in antiferromagnetic tunnel junctions (AFMTJs) and produce a giant tunneling magnetoresistance (TMR) effect. Using RuO
as a representative compensated antiferromagnet exhibiting spin-independent conductance along the 001 direction but a non-spin-degenerate Fermi surface, we design a RuO
/TiO
/RuO
(001) AFMTJ, where a globally spin-neutral charge current is controlled by the relative orientation of the Néel vectors of the two RuO
electrodes, resulting in the TMR effect as large as ~500%. These results are expanded to normal metals which can be used as a counter electrode in AFMTJs with a single antiferromagnetic layer or other elements in spintronic devices. Our work uncovers an unexplored potential of the materials with no global spin polarization for utilizing them in spintronics.
The law of momentum conservation rules out many desired processes in optical microresonators. We report broadband momentum transformations of light in asymmetric whispering gallery microresonators. ...Assisted by chaotic motions, broadband light can travel between optical modes with different angular momenta within a few picoseconds. Efficient coupling from visible to near-infrared bands is demonstrated between a nanowaveguide and whispering gallery modes with quality factors exceeding 10 million. The broadband momentum transformation enhances the device conversion efficiency of the third-harmonic generation by greater than three orders of magnitude over the conventional evanescent-wave coupling. The observed broadband and fast momentum transformation could promote applications such as multicolor lasers, broadband memories, and multiwavelength optical networks.
Organic frameworks represent an emerging family of advanced materials that can be precisely controlled at the atomic level. However, morphology control of organic frameworks remains perplexing and ...difficult, strongly limiting the advantages of organic frameworks in multiple practical applications. Herein, porphyrin organic framework hollow spheres (POF‐HSs) are fabricated by a template method as a proof of concept of organic frameworks with precisely controlled morphology. POF‐HS exhibits explicit chemical structures of 2D POF and an expected hollow structure. The morphology of POF‐HS is further regulated in terms of void size and shell thickness. Benefited from the polar chemical structures and the hollow spherical morphology, POF‐HS sufficiently mitigates the shuttle of polysulfides by taking the dual effects of chemical adsorption and physical confinement and functions as a desirable host material for sulfur cathode to endow lithium–sulfur batteries with high capacity, long cycling life, and excellent rate performance. The accurate synthesis of POF‐HSs demonstrates the highly controllable and versatile morphology of organic framework materials beyond precise integration of organic building blocks and represents infinite possibility of offering exotic organic frameworks for chemistry, sustainable energy, and material science.
Porphyrin organic framework hollow spheres (POF‐HSs) are synthesized using a template method. POF‐HS exhibits well‐defined chemical structures of organic frameworks and controllable morphology that can be precisely regulated in size and thickness. POF‐HS functions as a desirable host for the sulfur cathode in lithium–sulfur batteries, enabling high capacity, long‐term stability, and excellent rate performance.
Response to Bolia Zhang, Shu-Cheng
The American journal of gastroenterology,
10/2023, Letnik:
118, Številka:
10
Journal Article
Recenzirano
...the pelvic floor dysfunctions (PFDs) in children are not overcalled; on the contrary, they are underestimated. ...high-resolution anorectal manometry (HR-ARM) is a perfect method for the diagnosis ...of PFDs because it owns the technical characters of both traditional manometry and balloon expulsion test. ...I am sorry to say we have made a confusing table.