Spin Polarization: A New Frontier in Efficient Photocatalysis for Environmental Purification and Energy Conversion.

As a promising strategy to improve photocatalytic efficiency, spin polarization has attracted enormous attention in recent years, which could be involved in various steps of photoreaction. The Pauli repulsion principle and the spin selection rule dictate that the behavior of two electrons in a spatial eigenstate is based on their spin states, and this fact opens up a new avenue for manipulating photocatalytic efficiency. In this review, recent advances in modulating the photocatalytic activity with spin polarization are systematically summarized. Fundamental insights into the influence of spin-polarization effects on photon absorption, carrier separation, and migration, and the behaviors of reaction-related substances from the photon uptake to reactant desorption are highlighted and discussed in detail, and various photocatalytic applications for environmental purification and energy conversion are presented. This review is expected to deliver a timely overview of the recent developments in spin-polarization-modulated photocatalysis for environmental purification and energy conversion in terms of their practical applications.

Giant Out-of-Plane Exciton Emission Enhancement in Two-Dimensional Indium Selenide via a Plasmonic Nanocavity.

Out-of-plane (OP) exciton-based emitters in two-dimensional semiconductor materials are attractive candidates for novel photonic applications, such as radially polarized sources, integrated photonic chips, and quantum communications. However, their low quantum efficiency resulting from forbidden transitions limits their practicality. In this work, we achieve a giant enhancement of up to 34000 for OP exciton emission in indium selenide (InSe) via a designed Ag nanocube-over-Au film plasmonic nanocavity. The large photoluminescence enhancement factor (PLEF) is attributed to the induced OP local electric field (Ez) within the nanocavity, which facilitates effective OP exciton-plasmon interaction and subsequent tremendous enhancement. Moreover, the nanoantenna effect resulting from the effective interaction improves the directivity of spontaneous radiation. Our results not only reveal an effective photoluminescence enhancement approach for OP excitons but also present an avenue for designing on-chip photonic devices with an OP dipole orientation.

Selective Photoreforming of Waste Plastics into Diesel Olefins via Single Reactive Oxygen Species.

The accumulation of plastic waste poses a pressing environmental challenge. Catalytic conversion stands out as an ideal approach for plastics upcycling, particularly through solar-driven plastics photoreforming. However, due to the common effects of multiple reactive oxygen species (ROS), selectively generating high-value chemicals becomes challenging. In this study, we developed a universal strategy to achieve >85 % selective production of diesel olefins (C15-C28) from polyolefin waste plastics via single ROS. Using tetrakis (4-carboxyphenyl) porphyrin supramolecular (TCPP) with different central metals as an example to regulate single ROS generation, results show Ni-TCPP facilitates triplet exciton production, yielding 1O2, while Zn-TCPP generates ⋅O2 - due to its strong built-in electric field (IEF). 1O2 directly dechlorinates polyvinyl chloride (PVC) due to the electro-negativity of chlorine atoms and the low dissociation energy of C-Cl bonds, while ⋅O2 - promotes direct dehydrogenation of polyethylene (PE) due to the electro-positivity of hydrogen atoms and the high dissociation energy of C-H bonds. This method is universally applicable to various single ROS systems. Installation experiments further affirm the application potential, achieving the highest diesel olefin production of 76.1 µmol h-1. Such a universally adaptive approach holds promise for addressing the global plastic pollution problem.

Nasal Spray of Neutralizing Monoclonal Antibody 35B5 Confers Potential Prophylaxis Against Severe Acute Respiratory Syndrome Coronavirus 2 Variants of Concern: A Small-Scale Clinical Trial.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs), especially the Delta and Omicron variants, have been reported to show significant resistance to approved neutralizing monoclonal antibodies (mAbs) and vaccines. We previously identified a mAb named 35B5 that harbors broad neutralization to SARS-CoV-2 VOCs. Herein, we explored the protection efficacy of a 35B5-based nasal spray against SARS-CoV-2 VOCs in a small-scale clinical trial. METHODS: We enrolled 30 healthy volunteers who were nasally administered the modified 35B5 formulation. At 12, 24, 48, and 72 hours after nasal spray, the neutralization efficacy of nasal mucosal samples was assayed with pseudoviruses coated with SARS-CoV-2 spike protein of the wild-type strain or the Alpha, Beta, Delta, or Omicron variants. RESULTS: The nasal mucosal samples collected within 24 hours after nasal spray effectively neutralized SARS-CoV-2 VOCs (including Delta and Omicron). Meanwhile, the protection efficacy was 60% effective and 20% effective at 48 and 72 hours after nasal spray, respectively. CONCLUSIONS: A single nasal spray of 35B5 formation conveys 24-hour effective protection against SARS-CoV-2 VOCs, including the Alpha, Beta, Delta, or Omicron variants. Thus, 35B5 nasal spray might be potential in strengthening SARS-CoV-2 prevention, especially in high-risk populations. CLINICAL TRIALS REGISTRATION: 2022-005-02-KY.

All Optical Switching through Anistropic Gain of CsPbBr3 Single Crystal Microplatelet.

Perovskite micro/nanostructures have recently emerged as a highly attractive gain material for nanolasers. To explore their applications and further improve performance, it is essential to understand the optical gain and the anisotropic properties. Herein, we obtained high quality CsPbBr3 microplatelets (MP) with anisotropic orthorhombic phase. Optical gain of CsPbBr3 single crystal MP was investigated via microscale variable stripe-length measurement. A polarization-dependent optical gain was observed, and the gain along [002] was larger than that of [1-10]. The behavior was attributed to the lowest energy transition dipole moment of [002] induced by the smaller deviation of Br-Pb-Br bond from the perfect lattice. Along the [002] direction, we obtained the optical gain value up to 5077 cm-1, which is the record value ever reported. Moreover, all optical switching of lasing is realized by periodical polarized excitation. Our results provide new perceptions in the design of novel functional anisotropic devices based on perovskite micro/nanostructures.

Ultrafast Internal Exciton Dissociation through Edge States in MoS2 Nanosheets with Diffusion Blocking.

Edge states of two-dimensional transition-metal dichalcogenides (TMDCs) are crucial to quantum circuits and optoelectronics. However, their dynamics are pivotal but remain unclear due to the edge states being obscured by their bulk counterparts. Herein, we study the state-resolved transient absorption spectra of ball-milling-produced MoS2 nanosheets with 10 nm lateral size with highly exposed free edges. Electron energy loss spectroscopy and first-principles calculations confirm that the edge states are located in the range from 1.23 to 1.78 eV. Upon above bandgap excitations, excitons populate and diffuse toward the boundary, where the potential gradient blocks excitons and the edge states are formed through interband transitions within 400 fs. With below bandgap excitations, edge states are slowed down to 1.1 ps due to the weakened valence orbital coupling. These results shed light on the fundamental exciton dissociation processes on the boundary of functionalized TMDCs, enabling the ground work for applications in optoelectronics and light-harvesting.

Efficient Removal of Antibiotic Resistance Genes through 4f-2p-3d Gradient Orbital Coupling Mediated Fenton-Like Redox Processes.

Peroxymonosulfate (PMS) mediated radical and nonradical active substances can synergistically achieve the efficient elimination of antibiotic resistance genes (ARGs). However, enhancing interface electron cycling and optimizing the coupling of the oxygen-containing intermediates to improve PMS activation kinetics remains a major challenge. Here, Co doped CeVO4 catalyst (Co-CVO) with asymmetric sites was constructed based on Ce 4f-O 2p-Co 3d gradient orbital coupling. The catalyst achieved approximately 2.51×105 copies/mL of extracellular ARGs (eARGs) removal within 15 minutes, exhibited ultrahigh degradation rate (k=1.24 min-1 ). The effective gradient 4f-2p-3d orbital coupling precisely regulates the electron distribution of Ce-O-Co active center microenvironment, while optimizing the electronic structure of Co 3d states (especially the occupancy of eg ), promoting the adsorption of oxygen-containing intermediates. The generated radical and nonradical generated by interfacial electron cycling enhanced by the reduction reaction of PMS at the Ce site and the oxidation reaction at the Co site achieved a significant mineralization rate of ARGs (83.4 %). The efficient removal of ARGs by a continuous flow reactor for 10 hours significantly reduces the ecological risk of ARGs in actual wastewater treatment.

Excited-state dynamics of all-trans protonated retinal Schiff base in CRABPII-based rhodopsin mimics.

The rhodopsin mimic is a chemically synthetized complex with retinyl Schiff base (RSB) formed between protein and the retinal chromophore that can mimic the natural rhodopsin-like protein. The artificial rhodopsin mimic is more stable and designable than the natural protein and hence has wider uses in photon detection devices. The mimic structure RSB, like the case in the actual rhodopsin-like protein, undergoes isomerization and protonation throughout the photoreaction process. As a result, understanding the dynamics of the RSB in the photoreaction process is critical. In this study, the ultrafast transient absorption spectra of three mutants of the cellular retinoic acid-binding protein II-based rhodopsin mimic at acidic environment were recorded, from which the related excited-state dynamics of the all-trans protonated RSB (AT-PRSB) were investigated. The transient fluorescence spectra measurements are used to validate some of the dynamic features. We find that the excited-state dynamics of AT-PRSB in three mutants share a similar pattern that differs significantly from the dynamics of 15-cis PRSB of the rhodopsin mimic in neutral solution. By comparing the dynamics across the three mutants, we discovered that the aromatic residues near the ß-ionone ring structure of the retinal may help stabilize the AT-PRSB and hence slow down its isomerization rate. The experimental results provide implications on designing a rhodopsin-like protein with significant infrared fluorescence, which can be particularly useful in the applications in biosensing or bioimaging in deeper tissues.

Integration of Highly Luminescent Lead Halide Perovskite Nanocrystals on Transparent Lead Halide Nanowire Waveguides through Morphological Transformation and Spontaneous Growth in Water.

The integration of highly luminescent CsPbBr3 quantum dots on nanowire waveguides has enormous potential applications in nanophotonics, optical sensing, and quantum communications. On the other hand, CsPb2 Br5 nanowires have also attracted a lot of attention due to their unique water stability and controversial luminescent property. Here, the growth of CsPbBr3 nanocrystals on CsPb2 Br5 nanowires is reported first by simply immersing CsPbBr3 powder into pure water, CsPbBr3- γ Xγ (X = Cl, I) nanocrystals on CsPb2 Br5 -γ Xγ nanowires are then synthesized for tunable light sources. Systematic structure and morphology studies, including in situ monitoring, reveal that CsPbBr3 powder is first converted to CsPb2 Br5 microplatelets in water, followed by morphological transformation from CsPb2 Br5 microplatelets to nanowires, which is a kinetic dissolution-recrystallization process controlled by electrolytic dissociation and supersaturation of CsPb2 Br5 . CsPbBr3 nanocrystals are spontaneously formed on CsPb2 Br5 nanowires when nanowires are collected from the aqueous solution. Raman spectroscopy, combined photoluminescence, and SEM imaging confirm that the bright emission originates from CsPbBr3 -γ Xγ nanocrystals while CsPb2 Br5 -γ Xγ nanowires are transparent waveguides. The intimate integration of nanoscale light sources with a nanowire waveguide is demonstrated through the observation of the wave guiding of light from nanocrystals and Fabry-Perot interference modes of the nanowire cavity.

3D-printed silica with nanoscale resolution.

Fabricating inorganic materials with designed three-dimensional nanostructures is an exciting yet challenging area of research and industrial application. Here, we develop an approach to 3D print high-quality nanostructures of silica with sub-200 nm resolution and with the flexible capability of rare-earth element doping. The printed SiO2 can be either amorphous glass or polycrystalline cristobalite controlled by the sintering process. The 3D-printed nanostructures demonstrate attractive optical properties. For instance, the fabricated micro-toroid optical resonators can reach quality factors (Q) of over 104. Moreover, and importantly for optical applications, doping and codoping of rare-earth salts such as Er3+, Tm3+, Yb3+, Eu3+ and Nd3+ can be directly implemented in the printed SiO2 structures, showing strong photoluminescence at the desired wavelengths. This technique shows the potential for building integrated microphotonics with silica via 3D printing.

Tunable surface plasmon resonance sensor based on graphene-coated photonic crystal fiber in terahertz.

A terahertz surface plasmon resonance (SPR) sensor is designed based on photonic crystal fiber (PCF). Graphene is selectively coated in the cladding hole of the PCF and used as plasmonic material. The coupling mechanism, loss properties, tunability, and refractive index sensing performance of the designed SPR sensor are investigated using the finite element method. The peak of the loss spectrum corresponding to the SPR frequency can be dynamically tuned by adjusting graphene's chemical potential, and a tuning sensitivity of 767.5 GHz/eV is obtained. The SPR frequency red shifts linearly with an increase in the refractive index of analyte from 1.0 to 1.5. An average frequency sensitivity of 208.14 GHz/RIU is obtained. This research provides theoretical guidance for the design of terahertz in-fiber SPR sensors and filters.

Gold-implanted plasmonic quartz plate as a launch pad for laser-driven photoacoustic microfluidic pumps.

Enabled initially by the development of microelectromechanical systems, current microfluidic pumps still require advanced microfabrication techniques to create a variety of fluid-driving mechanisms. Here we report a generation of micropumps that involve no moving parts and microstructures. This micropump is based on a principle of photoacoustic laser streaming and is simply made of an Au-implanted plasmonic quartz plate. Under a pulsed laser excitation, any point on the plate can generate a directional long-lasting ultrasound wave which drives the fluid via acoustic streaming. Manipulating and programming laser beams can easily create a single pump, a moving pump, and multiple pumps. The underlying pumping mechanism of photoacoustic streaming is verified by high-speed imaging of the fluid motion after a single laser pulse. As many light-absorbing materials have been identified for efficient photoacoustic generation, photoacoustic micropumps can have diversity in their implementation. These laser-driven fabrication-free micropumps open up a generation of pumping technology and opportunities for easy integration and versatile microfluidic applications.

Analysis of risk factors for complications of perforator propeller flaps used for soft tissue reconstruction after malignant tumor resection: A systematic review and meta-analysis.

BACKGROUND: Perforator propeller flaps (PPFs) have been widely used due to their numerous advantages; however, they were also associated with various complications. Herein, we analyzed the risk factors for complications of PPFs used for soft tissue reconstruction after malignant tumor resection. METHODS: We searched databases for articles on soft tissue reconstruction using PPFs after malignant tumor resection published between January 1991 and April 2021. Studies were selected according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Fixed effects models and relative risks were used for data analysis. Funnel plots and Begg's test were used to evaluate publication bias. RESULTS: Twenty-six articles met the inclusion criteria. Complications were found in 24.7% of all patients. The four significant risk factors were age equal or older than 60 years (pooled relative risk, 1.83; p = .04), smoking (pooled relative risk, 2.32; p = .03), diabetes (pooled relative risk, 2.59; p = .01) and radiotherapy (pooled relative risk, 2.09; p = .01). Hypertension, defects located in the extremities, flap size equal or greater than 100 cm2 , and pedicle rotation equal or greater than 120 degrees were not significant risk factors for complications. No publication bias was found in the included articles. CONCLUSION: Age equal or older than 60 years, smoking, diabetes and radiotherapy are four risk factors for complications when PPFs are used to reconstruct soft tissue defects resulting from malignant tumor resection.

A Systematic Review And Meta-Analysis: Botulinum Toxin A Effect on Postoperative Facial Scar Prevention.

BACKGROUND: Postoperative facial scarring can be a significant psychological burden for patients to carry after surgery, often resulting in prolonged mental health dysfunction. Currently, there is no established method to prevent facial scar formation; however, there are several methods to prevent facial scar hyperplasia and improve scar quality. Botulinum toxin A (BTA) has been widely used due to its properties of muscle paralysis and known success in plastic surgery and cosmetology. This meta-analysis aimed to evaluate the efficacy of BTA in preventing postoperative facial scar hyperplasia and improving scar quality. METHODS: PubMed, MEDLINE, EMBASE, web of science, and Cochrane libraries were searched for randomized controlled trials (RCTs) (published before May 2021) wherein BTA was used for the treatment of facial scars. The efficacy and safety of BTA were evaluated by the following scales: the Vancouver Scar Scale (VSS), Visual Analog Scale (VAS), Observer Scar Assessment Scale (OSAS), Patient Scar Assessment Scale (PSAS), and Stony Brook Scar Evaluation Scale (SBSES); the BTA effect on scar width and complications was also assessed. RESULTS: Ten RCTs involving 114 cases were included. Through quantitative analysis, the BTA injection group had a higher VAS score, lower VSS score, lower OSAS score, and smaller scar width. However, no significant difference was noted in the incidence of postoperative complications between the two groups. CONCLUSIONS: This meta-analysis demonstrated that BTA can safely improve the appearance of postoperative facial scars by significantly inhibiting scar hyperplasia and improving scar quality. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Qualitative Exploration of the Psychological Experience of Patients Hospitalized With COVID-19.

This qualitative study describes the psychological experience of patients hospitalized with COVID-19. These patients went through 3 psychological stages: extremely uncertainties during the initial diagnostic stage, complicated feelings of negativity during the treatment stage, and positive growth in the recovery stage. It is important for nurses to provide holistic care.

Efficient Long-Range Triplet Exciton Transport by Metal-Metal Interaction at Room Temperature.

Efficient and long-range exciton transport is critical for photosynthesis and opto-electronic devices, and for triplet-harvesting materials, triplet exciton diffusion length ( L D ) and coefficient ( D ) are key parameters in determining their performances. Herein, we observed that PtII and PdII organometallic nanowires exhibit long-range anisotropic triplet exciton LD of 5-7 µm along the M-M direction using direct photoluminescence (PL) imaging technique by low-power continuous wave (CW) laser excitation. At room temperature, via a combined triplet-triplet annihilation (TTA) analysis and spatial PL imaging, an efficient triplet exciton diffusion was observed for the PtII and PdII nanowires with extended close M-M contact, while is absent in nanowires without close M-M contact. Two-dimensional electronic spectroscopy (2DES) and calculations revealed a significant contribution of the delocalized 1/3 [dσ*(M-M)→π*] excited state during the exciton diffusion modulated by the M-M distance.

The Epigenetic Regulator EZH2 Instructs CD4 T Cell Response to Acute Viral Infection via Coupling of Cell Expansion and Metabolic Fitness.

The protection of a majority of viral vaccines is mediated by CD4 T cell-dependent humoral immunity. The methyltransferase enhancer of zeste homolog 2 (EZH2) dictates the differentiation of naive CD4 T cells into distinct effector T helper subsets at the onset of acute viral infection. However, whether and how EZH2 manipulates differentiated virus-specific CD4 T cell expansion remain to be elucidated. Here, we found that EZH2 is integral for virus-specific CD4 T cell expansion in a mouse model of acute viral infection. By a mechanism that involves fine-tuning the mechanistic target of rapamycin (mTOR) signaling, EZH2 participates in integrating metabolic pathways to support cell expansion. The genetic ablation of EZH2 leads to impaired cellular metabolism and, consequently, poor CD4 T cell response to acute viral infection. Thus, we identified EZH2 as a novel regulator in virus-specific CD4 T cell expansion during acute viral infection.IMPORTANCE The CD4 T cell response is critical in curtailing viral infection or eliciting efficacious viral vaccination. Highly efficient expansion of virus-specific CD4 T cells culminates in a qualified CD4 T cell response. Here, we found that the epigenetic regulator EZH2 is a prerequisite for the virus-specific CD4 T cell response, with a mechanism coupling cell expansion and metabolism. Thus, our study provides valuable insights for strategies targeting EZH2 to improve the efficacy of CD4 T cell-based viral vaccines and to help treat diseases associated with aberrant CD4 T cell responses.

Photoacoustic laser streaming with non-plasmonic metal ion implantation in transparent substrates.

Photoacoustic laser streaming provides a versatile technique to manipulate liquids and their suspended objects with light. However, only gold was used in the initial demonstrations. In this work, we first demonstrate that laser streaming can be achieved with common non-plasmonic metals such as Fe and W by their ion implantations in transparent substrates. We then investigate the effects of ion dose, substrate material and thickness on the strength and duration of streaming. Finally, we vary laser pulse width, repetition rate and power to understand the observed threshold power for laser streaming. It is found that substrate thickness has a negligible effect on laser streaming down to 0.1 mm, glass and quartz produce much stronger streaming than sapphire because of their smaller thermal conductivity, while quartz exhibits the longest durability than glass and sapphire under the same laser intensity. Compared with Au, Fe and W with higher melting points show a longer lifetime although they require a higher laser intensity to achieve a similar speed of streaming. To generate a continuous laser streaming, the laser must have a minimum pulse repetition rate of 10 Hz and meet the minimum pulse width and energy to generate a transient vapor layer. This vapor layer enhances the generation of ultrasound waves, which are required for observable fluid jets. Principles of laser streaming and temperature simulation are used to explain these observations, and our study paves the way for further materials engineering and device design for strong and durable laser streaming.

Novel insight from the first lung transplant of a COVID-19 patient.

BACKGROUND: To reveal detailed histopathological changes, virus distributions, immunologic properties and multi-omic features caused by SARS-CoV-2 in the explanted lungs from the world's first successful lung transplantation of a COVID-19 patient. MATERIALS AND METHODS: A total of 36 samples were collected from the lungs. Histopathological features and virus distribution were observed by optical microscope and transmission electron microscope (TEM). Immune cells were detected by flow cytometry and immunohistochemistry. Transcriptome and proteome approaches were used to investigate main biological processes involved in COVID-19-associated pulmonary fibrosis. RESULTS: The histopathological changes of the lung tissues were characterized by extensive pulmonary interstitial fibrosis and haemorrhage. Viral particles were observed in the cytoplasm of macrophages. CD3+ CD4- T cells, neutrophils, NK cells, γ/δ T cells and monocytes, but not B cells, were abundant in the lungs. Higher levels of proinflammatory cytokines iNOS, IL-1ß and IL-6 were in the area of mild fibrosis. Multi-omics analyses revealed a total of 126 out of 20,356 significant different transcription and 114 out of 8,493 protein expression in lung samples with mild and severe fibrosis, most of which were related to fibrosis and inflammation. CONCLUSIONS: Our results provide novel insight that the significant neutrophil/ CD3+ CD4- T cell/ macrophage activation leads to cytokine storm and severe fibrosis in the lungs of COVID-19 patient and may contribute to a better understanding of COVID-19 pathogenesis.

Edge Raman enhancement at layered PbI2platelets induced by laser waveguide effect.

As a two-dimensional (2D) layered semiconductor, lead iodide (PbI2) has been widely used in optoelectronics owing to its unique crystal structure and distinctive optical and electrical properties. A comprehensive understanding of its optical performance is essential for further application and progress. Here, we synthesized regularly shaped PbI2platelets using the chemical vapor deposition method. Raman scattering spectroscopy of PbI2platelets was predominantly enhanced when the laser radiated at the edge according to Raman mapping spectroscopy. Combining the outcome of polarized Raman scattering spectroscopy and finite-difference time domain simulation analysis, the Raman enhancement was proven to be the consequence of the enhancement effects inherent to the high refractive index contrast waveguide, which is naturally formed in well-defined PbI2platelets. Because of the enlarged excited area determined by the increased propagation length of the laser in the PbI2platelet formed waveguide, the total Raman enhancements are acquired rather than a localized point enhancement. Finally, the Raman enhancement factor is directly related to the thickness of the PbI2platelet, which further confirms the waveguide-enhanced edge Raman. Our investigation of the optical properties of PbI2platelets offers reference for potential 2D layered-related optoelectronic applications.