Backscattering suppression in silicon-on-insulator (SOI) is one of the central issues to reduce energy loss and signal distortion, enabling for capability improvement of modern information processing ...systems. Valley physics provides an intriguing way for robust information transfer and unidirectional coupling in topological nanophotonics. Here we realize topological transport in a SOI valley photonic crystal slab. Localized Berry curvature near zone corners guarantees the existence of valley-dependent edge states below light cone, maintaining in-plane robustness and light confinement simultaneously. Topologically robust transport at telecommunication is observed along two sharp-bend interfaces in subwavelength scale, showing flat-top high transmission of ~10% bandwidth. Topological photonic routing is achieved in a bearded-stack interface, due to unidirectional excitation of valley-chirality-locked edge state from the phase vortex of a nanoscale microdisk. These findings show the prototype of robustly integrated devices, and open a new door towards the observation of non-trivial states even in non-Hermitian systems.
Critical patients with the coronavirus disease 2019 (COVID-19), even those whose nucleic acid test results had turned negative and those receiving maximal medical support, have been noted to progress ...to irreversible fatal respiratory failure. Lung transplantation (LT) as the sole therapy for end-stage pulmonary fibrosis related to acute respiratory distress syndrome has been considered as the ultimate rescue therapy for these patients.
From February 10 to March 10, 2020, three male patients were urgently assessed and listed for transplantation. After conducting a full ethical review and after obtaining assent from the family of the patients, we performed three LT procedures for COVID-19 patients with illness durations of more than one month and extremely high sequential organ failure assessment scores.
Two of the three recipients survived post-LT and started participating in a rehabilitation program. Pearls of the LT team collaboration and perioperative logistics were summarized and continually improved. The pathological results of the explanted lungs were concordant with the critical clinical manifestation, and provided insight towards better understanding of the disease. Government health affair systems, virology detection tools, and modern communication technology all play key roles towards the survival of the patients and their rehabilitation.
LT can be performed in end-stage patients with respiratory failure due to COVID-19-related pulmonary fibrosis. If confirmed positive-turned-negative virology status without organ dysfunction that could contraindicate LT, LT provided the final option for these patients to avoid certain death, with proper protection of transplant surgeons and medical staffs. By ensuring instant seamless care for both patients and medical teams, the goal of reducing the mortality rate and salvaging the lives of patients with COVID-19 can be attained.
High‐nickel (Ni ≥ 90%) cathodes with high specific capacity hold great potential for next‐generation lithium‐ion batteries (LIBs). However, their practical application is restricted by the high ...interfacial reactivity under continuous air erosion and electrolyte assault. Herein, a stable high‐nickel cathode is rationally designed via in situ induction of a dense amorphous Li2CO3 on the particle surface by a preemptive atmosphere control. Among the residual lithium compounds, Li2CO3 is the most thermodynamically stable one, so a dense Li2CO3 coating layer can serve as a physical protection layer to isolate the cathode from contact with moist air. Furthermore, amorphous Li2CO3 can be transformed into a robust F‐rich cathode electrolyte interphase (CEI) during cycling, which reinforces the cathode's interfacial stability and improves the electrochemical performance. The assembled coin cell with this modified cathode delivers a high discharge capacity of 232.4 mAh g–1 with a superior initial Coulombic efficiency (CE) of 95.1%, and considerable capacity retention of 90.4% after 100 cycles. Furthermore, no slurry gelation occurs during the large‐scale electrode fabrication process. This work opens a valuable perspective on the evolution of amorphous Li2CO3 in LIBs and provides guidance on protecting unstable high‐capacity cathodes for energy‐storage devices.
A high‐nickel cathode (Ni ≥ 90%) is developed through controlling the surface residual lithium composition with a formed amorphous Li2CO3 protective layer. This cathode can resist corrosion by air, and will be converted into a stable cathode electrolyte interphase during the electrochemical process, resulting in enhanced storage performance and extended cycle life for high‐nickel cathodes.
Invasion of microbial DNA into the cytoplasm of animal cells triggers a cascade of host immune reactions that help clear the infection; however, self DNA in the cytoplasm can cause autoimmune ...diseases. Biochemical approaches led to the identification of cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) as a cytosolic DNA sensor that triggers innate immune responses. Here, we show that cells from cGAS-deficient (cGas -/- ) mice, including fibroblasts, macrophages, and dendritic cells, failed to produce type I interferons and other cytokines in response to DNA transfection or DNA virus infection. cGas -/- mice were more susceptible to lethal infection with herpes simplex virus 1 (HSV1) than wild-type mice. We also show that cGAMP is an adjuvant that boosts antigen-specific T cell activation and antibody production in mice.
Recently, higher-order topological phases that do not obey the usual bulk-edge correspondence principle have been introduced in electronic insulators and brought into classical systems, featuring ...in-gap corner or hinge states. In this Letter, using near-field scanning measurements, we show the direct observation of corner states in second-order topological photonic crystal slabs consisting of periodic dielectric rods on a perfect electric conductor. Based on the generalized two-dimensional Su-Schrieffer-Heeger model, we show that the emergence of corner states roots in the nonzero edge dipolar polarization instead of the nonzero bulk quadrupole polarization. We demonstrate the topological transition of two-dimensional Zak phases of photonic crystal slabs by tuning intracell distances between two neighboring rods. We also directly observe in-gap one-dimensional edge states and zero-dimensional corner states in the microwave regime. Our work presents that the photonic crystal slab is a powerful platform to directly observe topological states and paves the way to study higher-order photonic topological insulators.
Photonic crystals offer unprecedented opportunity for light manipulation and applications in optical communication and sensing. Exploration of topology in photonic crystals and metamaterials with ...non-zero gauge field has inspired a number of intriguing optical phenomena such as one-way transport and Weyl points. Recently, a new degree of freedom, valley, has been demonstrated in two-dimensional materials. Here, we propose a concept of valley photonic crystals with electromagnetic duality symmetry but broken inversion symmetry. We observe photonic valley Hall effect originating from valley-dependent spin-split bulk bands, even in topologically trivial photonic crystals. Valley-spin locking behaviour results in selective net spin flow inside bulk valley photonic crystals. We also show the independent control of valley and topology in a single system that has been long pursued in electronic systems, resulting in topologically-protected flat edge states. Valley photonic crystals not only offer a route towards the observation of non-trivial states, but also open the way for device applications in integrated photonics and information processing using spin-dependent transportation.
Recent research in topological photonics has not only proposed and realized novel topological phenomena such as one‐way broadband propagation and robust transport of light, but also designed and ...fabricated photonic devices with high‐performance indexes, which are immune to fabrication errors such as defects or disorders. Photonic crystals, which are periodic optical structures with the advantages of good light field confinement and multiple adjusting degrees of freedom, provide a powerful platform to control the flow of light. With the topology defined in the reciprocal space, photonic crystals have been widely used to reveal different topological phases of light and demonstrate topological photonic functionalities. This review presents the physics of topological photonic crystals with different dimensions, models, and topological phases. The design methods of topological photonic crystals are introduced. Furthermore, the applications of topological photonic crystals in passive and active photonics are reviewed. These studies pave the way for applying topological photonic crystals in practical photonic devices.
For the ability to improve the robustness of photonic devices under different kinds of defects, topological photonic crystals have attracted increasing attention and have been used as a platform for studying intriguing physical phenomena and realizing novel functional devices. This review provides an introduction to the fundamental physics, optical design, and promising applications of topological photonic crystals in different dimensions.
Background
With the increased prevalence of obesity and sarcopenia, those patients with both visceral obesity and sarcopenia were at higher risk of adverse outcomes.
Aim
The aim of this study was to ...ascertain the combined impact of visceral obesity and sarcopenia on short-term outcomes in patients undergoing colorectal cancer surgery.
Methods
We conducted a prospective study from July 2014 to February 2017. Patients’ demographic, clinical characteristics, physical performance, and postoperative short-term outcomes were collected. Patients were classified into four groups according to the presence of sarcopenia or visceral obesity. Clinical variables were compared. Univariate and multivariate analyses evaluating the risk factors for postoperative complications were performed.
Results
A total of 376 patients were included; 50.8 and 24.5% of the patients were identified as having “visceral obesity” and “sarcopenia,” respectively. Patients with sarcopenia and visceral obesity had the highest incidence of total, surgical, and medical complications. Patients with sarcopenia or/and visceral obesity all had longer hospital stays and higher hospitalization costs. Age ≥ 65 years, visceral obesity, and sarcopenia were independent risk factors for total complications. Rectal cancer and visceral obesity were independent risk factors for surgical complications. Age ≥ 65 years and sarcopenia were independent risk factors for medical complications. Laparoscopy-assisted operation was a protective factor for total and medical complications.
Conclusion
Patients with both visceral obesity and sarcopenia had a higher complication rate after colorectal cancer surgery. Age ≥ 65 years, visceral obesity, and sarcopenia were independent risk factors for total complications. Laparoscopy-assisted operation was a protective factor.
Gastric cancer is one of the most frequently diagnosed and the leading cause of cancer death worldwide. Malnutrition is a substantial problem in patients with gastric cancer, associated with poor ...treatment tolerance and increased morbidity. It has also been recognized as an independent prognostic factor in individuals with cancer. Early detection of malnutrition and effective perioperative nutrition intervention play an important role in the treatment of gastric cancer. Nutrition screening and assessment are the first steps in nutrition management and provide a basis for further nutrition support. Several tools, including the Nutrition Risk Screening-2002 and Patient-Generated Subjective Global Assessment, have been developed for nutrition screening and assessment. Effective nutrition support can significantly improve nutritional and immune status, reduce the incidence of postoperative complications, and accelerate recovery. The aim of this review was to focus on preoperative nutrition risk screening and assessment, and perioperative nutrition support, which may serve as a framework of perioperative nutrition management for gastric cancer.
Near‐infrared II (NIR‐II) imaging at 1100–1700 nm shows great promise for medical diagnosis related to blood vessels because it possesses deep penetration and high resolution in biological tissue. ...Unfortunately, currently available NIR‐II fluorophores exhibit slow excretion and low brightness, which prevents their potential medical applications. An atomic‐precision gold (Au) cluster with 25 gold atoms and 18 peptide ligands is presented. The Au25 clusters show emission at 1100–1350 nm and the fluorescence quantum yield is significantly increased by metal‐atom doping. Bright gold clusters can penetrate deep tissue and can be applied in in vivo brain vessel imaging and tumor metastasis. Time‐resolved brain blood‐flow imaging shows significant differences between healthy and injured mice with different brain diseases in vivo. High‐resolution imaging of cancer metastasis allows for the identification of the primary tumor, blood vessel, and lymphatic metastasis. In addition, gold clusters with NIR‐II fluorescence are used to monitor high‐resolution imaging of kidney at a depth of 0.61 cm, and the quantitative measurement shows 86% of the gold clusters are cleared from body without any acute or long‐term toxicity at a dose of 100 mg kg−1.
Near‐infrared II (NIR II) imaging at 1100–1700 nm with deep penetration and high resolution shows great promise for medical diagnosis. Ultrasmall gold clusters with 1100–1350 nm NIR IIa emission are developed and can penetrate the skull of mouse. In vivo cerebrovascular and tumor metastasis imaging show that they serve as an NIR‐II fluorescence agent with potential clinical transformation for medical diagnosis.
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