A kind of multiwavelength erbium-doped fiber laser based on Lyot filter

A multiwavelength tunable ring-cavity erbium-doped fiber laser(EDFL)based on a Lyot filter was presented.For the proposed Lyot filter,a comb filter consisting of an EDF-polarization-maintaining fiber(EDF-PMF),a polarization controller(PC),and a circulator with four ports was used to suppress the mode competition.The light transmission direction was guaranteed by the circulator.For the proposed fiber laser,tunable single,dual,triple,quadruple,quintuple,sextuple,and septuple wavelengths were realized.A single-wavelength laser output with an optical signal-to-noise ratio(SNR)of up to30.56 dB was realized,and a tuning range of 1590.54 nm to 1599.54 nm was achieved by tuning the PC.The stability of the single,dual,triple,and quadruple-wavelength center power fluctuations was less than 0.05 dB,0.98 dB,5.07 dB,and7.71 dB respectively.When the laser was operated in the multiwavelength condition,the SNR was more than 20.97 dB.The proposed erbium-doped fiber laser is suitable for fiber-sensing system applications.

Constructing Carbon Nanobubbles with Boron Doping as Advanced Anode for Realizing Unprecedently Ultrafast Potassium Ion Storage

Carbonaceous material with favorable K^(+)intercalation feature is considered as a compelling anode for potassium-ion batteries(PIBs).However,the inferior rate performance and cycling stability impede their large-scale application.Here,a facile template method is utilized to synthesize boron doping carbon nanobubbles(BCNBs).The incorporation of boron into the carbon structure introduces abundant defective sites and improves conductivity,facilitating both the intercalation-controlled and capacitivecontrolled capacities.Moreover,theoretical calculation proves that boron doping can effectively improve the conductivity and facilitate electrochemical reversibility in PIBs.Correspondingly,the designed BCNBs anode delivers a high specific capacity(464 mAh g^(-1)at 0.05 A g^(-1))with an extraordinary rate performance(85.7 mAh g^(-1)at 50 A g^(-1)),and retains a considerable capacity retention(95.2%relative to the 100th charge after 2000 cycles).Besides,the strategy of pre-forming stable artificial inorganic solid electrolyte interface effectively realizes high initial coulombic efficiency of 79.0%for BCNBs.Impressively,a dual-carbon potassium-ion capacitor coupling BCNBs anode displays a high energy density(177.8 Wh kg^(-1)).This work not only shows great potential for utilizing heteroatom-doping strategy to boost the potassium ion storage but also paves the way for designing high-energy/power storage devices.

Conduction-convection coupled heat transfer around a hollow cylinder under different buoyancy forces

In order to clarify the effect of a buoyancy force on conduction–convection coupled heat transfer in a hollow cylinder, the flow and thermal characteristics were analyzed using an RNG k-ε turbulence model. The Reynolds number was fixed at 1.014 × 10^(6), and the Rayleigh number varied from 1.122 × 10^(10)to 1.088 × 10^(11). Results have shown that, when considering the effect of an opposed buoyancy force, increasing the Rayleigh number has a positive impact on the rate of change and uniformity of the cylinder temperature. The temperature distributions along the axial and circumferential directions are similar for different Rayleigh numbers, but extreme values differ.Along the axial direction, the maximum temperature is obtained at the interface between the variable-diameter part and the constant-diameter part. The maximum dimensionless temperature value decreases to 0.12 when the Rayleigh number increases to 1.088 × 10^(11). Along the circumferential direction, the temperature distribution is affected by the buoyancy force, which results in the temperature of the upper part being higher than that of the lower part. After nondimensionalization of the temperature and time, a correlation was proposed to illustrate the transient heat transfer process quantitatively. The standard deviation of the maximum relative temperature, representing the temperature uniformity, was also calculated. It was found that the difference in the direction of the buoyancy force made a huge difference. Compared with the opposed buoyancy force, the maximum dimensionless temperature is almost two times higher with an assisted buoyancy force. Similarly, the heat transfer coefficient with an assisted buoyancy force is half of that with an opposed buoyancy force. Overall, an assisted buoyancy force plays a negative role in terms of thermal characteristics. The flow field around the hollow cylinder was also illustrated to reveal the mechanism of the buoyancy force on magnitude and direction aspects.

CAR-T cells for cancer immunotherapy

Adoptive immunotherapy expressing synthetic chimeric antigen receptors(CAR)on T cells through in vitro modifications represents a new and innovative strategy in cancer treatment.This new approach enables T cells to recognize and bind tumor antigens via a single-chain variable fragment recognition domain,circumventing the restriction of major histocompatibility complex.This review summarized the structure/design of CAR-T cells and the evolution process this technology went through,displaying the theoretical foundation for CAR-T therapy,the marketed products and the latest preclinical and clinical research progress.Finally,we provided perspectives on this technology’s development and potential future applications,especially for treating hematological malignant and solid tumors.

A cytochrome c551 mediates the cyclic electron transport chain of the anoxygenic phototrophic bacterium Roseiflexus castenholzii

Roseiflexus castenholzii is a gram-negativefilamentous phototrophic bacterium that carries out anoxygenic photosynthesis through a cyclic electron transport chain(ETC).The ETC is composed of a reaction center(RC)–light-harvesting(LH)complex(rcRC–LH);an alternative complex III(rcACIII),which functionally re-places the cytochrome bc1/b6f complex;and the periplasmic electron acceptor auracyanin(rcAc).Although compositionally and structurally different from the bc1/b6f complex,rcACIII plays similar essential roles in oxidizing menaquinol and transferring electrons to the rcAc.However,rcACIII-mediated electron transfer(which includes both an intraprotein route and a downstream route)has not been clearly elucidated,nor have the details of cyclic ETC.Here,we identify a previously unknown monoheme cytochrome c(cyt c551)as a novel periplasmic electron acceptor of rcACIII.It reduces the light-excited rcRC–LH to complete a cyclic ETC.We also reveal the molecular mechanisms involved in the ETC using electron paramagnetic resonance(EPR),spectroelectrochemistry,and enzymatic and structural analyses.Wefind that electrons released from rcACIII-oxidized menaquinol are transferred to two alternative periplasmic electron acceptors(rcAc and cyt c551),which eventually reduce the rcRC to form the complete cyclic ETC.This work serves as a foundation for further studies of ACIII-mediated electron transfer in anoxygenic photosynthesis and broadens our under-standing of the diversity and molecular evolution of prokaryotic ETCs.

CXXC5 suppresses hepatocellular carcinoma by promoting TGF-β-induced cell cycle arrest and apoptosis

Evading TGF-β-mediated growth inhibition is often associated with tumorigenesis in liver, including hepatocellular carcinoma （HCC）. To better understand the functions and the underlying molecular mechanisms of TGF-β in HCC initiation and progression, we carried out transcriptome sequencing （RNA-Seq） to identify the target genes of TGF-β. CXXCS, a member of the CXXC-type zinc finger domain-containing protein family, was identified as a novel TGF-β target gene in Hep3B HCC cells. Knockdown of CXXC5 attenuated the expression of a substantial portion of TGF-p target genes and ameliorated TGF-13-induced growth inhibition or apoptosis of Hep3B cells, suggesting that CXXC5 is required for TGF-p-mediated inhibition of HCC progression. Analysis of the TCGA database indicated that CXXC5 expression is reduced in the majority of HCC tissue samples in comparison to that in normal tissues. Furthermore, CXXC5 associates with the histone deacetylase HDAC1 and competes its interaction with Smad2/3, thereby abolishing the inhibitory effect of HDAC1 on TGF-β signaling. These observations together suggest that CXXC5 may act as a tumor suppressor by promoting TGF-β signaling via a positive feedback loop, and reveal a strategy for HCC to bypass TGF-β-mediated cytostasis by disrupting the positive feedback regulation. Our findings shed new light on TGF-β signaling regulation and demon- strate the function of CXXC5 in HCC development.

A review on perfluoroalkyl acids studies:Environmental behaviors,toxic effects,and ecological and health risks

Perfluoroalkyl acids(PFAAs)are emerging persistent organic pollutants that are globally distributed in the environment.In the present review,the occurrence of PFAAs and their behavior in aquatic ecosystem were summarized,and the health and ecological risk assessment and the multimedia fate simulation were investigated.PFAAs are most likely to exist in the aqueous phase,and PFAAs in atmosphere are also able to enter water bodies through diffusion and wet and dry deposition and eventually become widely distributed in various environmental media.The air-solid partition is considered to be one of the major factors in the long-distance transportation of the pollutants.The pKa values and organic carbon fraction of the sediment could influence the partition of PFAAs between water and sediment.Otherwise,PFAAs have teratogenic,mutagenic and other toxic effects and they could be accumulated by biota,and magnified through trophic level.The ecological and health risks of PFOA and PFOS were assessment.In order to explore the partition mechanism and reduce the uncertainty of the simulation of the transport,transformation and fate,the experimental methods on physicochemical properties of PFAAs should be developed.Moreover,further studies on toxicities of PFAAs are necessary for health and ecological risk assessment.

Vertically aligned two-dimensional materials-based thick electrodes for scalable energy storage systems

Together with the blooming of portable smart devices and electric vehicles in the last decade,electrochemical energy storage(EES)devices capable of high-energy and high-power storage are urgently needed.Two-dimensional(2D)materials,benefiting from the short solid-state diffusion distance,are well recognized to possess excellent electrochemical performance.However,liquid diffusion,the rate-determining process in thick electrodes,is notably slow in 2D materials-based electrodes stemming from their stacking during electrode processing,which considerably limits their applications for high energy storage.To fully exploit intrinsic advantages of 2D materials for scalable energy storage devices,this review summarizes several important strategies,ranging from assembly to template methods,to fabricate vertically aligned 2D materials-based electrodes.We further discuss the advantages and challenges of these methods in terms of key features of thick electrodes and illustrate the design principles for high-energy/power devices.

Study on Lithium Insertion in Lepidocrocite and ,λ-MnO2 Type TiO2： A First-Principles Prediction

TiO2 is a latent anode material for rechargeable lithium batteries. Our simulation models, basing lepidocrocite and 2-MnO2 type TiO2 were investigated by density functional theory （DFT）. The key issues are focused on the lithium insertion sites, electronic structures, and the conducting paths of Li＋ ions. Our calculated data indicate the calculated voltage of 2-MnO2 type TiO2 is higher than that of lepidocrocite type TiO2. The Li＋ ion migration energy barrier of lepidocroeite type YiO2 along the [1 0 0] direction （0.45 eV） is lower than that of along the [110] direction （0.57 eV）. The energy barriers of 2-MnO2 type TiO2 to move a Li＋ ion among the adjacent embedded sites （16c or 8a sites） is 0.68 eV.

In situ protection of a sulfur cathode and a lithium anode via adopting a fluorinated electrolyte for stable lithium-sulfur batteries

Lithium-sulfur(Li-S)batteries are regarded as one of the most promising next-generation energy storage systems due to their high theoretical energy density and low material cost.However,the conventional ether-based electrolytes of Li-S batteries are extremely flammable and have high solubility of lithium polysulfides(LiPS),resulting in a high safety risk and a poor life cycle.Herein,we report an ether/carbonate co-solvent fluorinated electrolyte with a special solvation sheath of Li^(+),which can prevent the formation of dissoluble long-chain LiPS of the sulfur cathode,restrict Li dendrite growth at the anode side,and show fire resistance in combustion experiments.As a result,the proposed Li-S batteries with 70 wt%sulfur content in its cathode deliver stable life cycle,low self-discharge ratio,and intrinsic safety.Therefore,the unique passivation characteristics of the designed fluorinated electrolyte break several critical limitations of the traditional“liquid phase”-based Li-S batteries,offering a facile and promising way to develop long-life and high-safety Li-S batteries.

Study on cyclic characteristics of the solar-powered adsorption cooling system

According to the typical variable heat source of solar energy and the unsteady adsorption process of adsorption chiller,the research of cyclic transient characteristics of the solar-powered adsorption cooling system is presented in this work.A mathematic model of the whole system including the model of adsorption chiller,which reveals the transient operation process of the solar-powered adsorption cooling system,is developed and verified by experimental data.On the basis of the simulated results,the transient characteristics and the overall performance of the system,not only in the traditional open cycle mode but also in closed cycle mode,are both analyzed theoretically.Furthermore,the influence of parameters matching of components configuration and operation process on the cyclic characteristics of the system,such as the solar collector area,the water tank capacity and the chiller startup temperature,are discussed.The research in this work may play a very important role in optimizing the system cyclic process and improving the system adaptability especially under the condition of variable heat source.

Plant G proteins interact with endoplasmic reticulum luminal protein receptors to regulate endoplasmic reticulum retrieval

Maintaining endoplasmic reticulum （ER） homeostasis is essential for the production of biomolecules. ER retrieval, i.e., the retrograde transport of compounds from the Golgi to the ER, is one of the pathways that ensures ER homeostasis. However, the mechanisms underlying the regulation of ER retrieval in plants remain largely unknown. Plant ERD2-1ike proteins （ERD2s） were recently suggested to function as ER luminal protein receptors that mediate ER retrieval. Here, we demon- strate that heterotrimeric G protein signaling is involved in ERD2-mediated ER retrieval. We show that ERD2s interact with the heterotrimeric G protein Gα and Gγsubunits at the Golgi. Silencing of Gα, Gβ, or Gγ increased the retention of ER luminal proteins. Furthermore, overexpression of Gα, Gβ, or Gγ caused ER luminal proteins to escape from the ER, as did the co-silencing of ERD2a and ERD2b. These results suggest that G proteins interact with ER luminal protein receptors to regulate ER retrieval.

Order-structuredsolid-stateelectrolytes

Solid-state electrolytes(SSEs)are recognized as attractive candidates to real-ize safe and high-energy-density lithium metal batteries(LMBs).However,the practical application of SSEs still faces challenges such as insufficient room-temperature ionic conductivity,unsatisfactory mechanical properties,and large internal resistance.Extensive research efforts have been made to explore new electrochemistry and technologies to address those challenges.Among them,the construction of order-structured SSEs has emerged as a promising strategy.The anisotropic behavior induced by the orientation offers SSEs with desired properties targeting specific functions,and therefore the rational design of the order-structured SSE provides an alternative solution to achieve an ideal SSE.This review discusses the structure-property correlation of SSEs,and then sum-marizes the design strategies to construct order-structured SSEs.Finally,the current challenges and possible future research directions for order-structured SSEs for scalable high-energy-density LMBs are presented.

Research Trends and Emerging Hotspots of Lung Cancer Surgery during 2012-2021:A 10-Year Bibliometric and Network Analysis

Background. Lung cancer remains the leading cause of death because of cancer globally in the past years. To inspire researcherswith new targets and path-breaking directions for lung cancer research, this study is aimed at exploring the research trends andemerging hotspots in the lung cancer surgery literature in the recent decade. Methods. This cross-sectional study combinedbibliometric and network analysis techniques to undertake a quantitative analysis of lung cancer surgery literature. Dimensionsdatabase was searched using keywords in a 10-year period (2012-2021). Publications were characterized by publication year,research countries, field citation ratio, cooperation status, research area, and emerging hotspots. Results. Overall, globalscholarly outputs of lung cancer surgery had almost doubled during the recent decade, with China, Japan, and the UnitedStates leading the way, while Denmark and Belgium predominated in terms of scientific influence. Network analysis showedthat international cooperation accounted for a relatively small portion in lung cancer surgery research, and the United States,China, and Europe were the prominent centers of international cooperation network. In the recent decade, research of lungcancer surgery majored in prevention, biomedical imaging, rehabilitation, and genetics, and the emerging research hotspotstransformed into immunotherapy. Research on immunotherapy showed a considerable increase in scientific influence in thelatest year. Conclusions. The study findings are expected to provide researchers and policymakers with interesting insights intothe changing trends of lung cancer surgery research and further generate evidence to support decision-making in improvingprognosis for patients with lung cancer.

Sustainable nanostructured electrolyte additives for stable metal anodes

Metal anodes(e.g.,Li and Zn)are promising candidates for high-energy and high-power rechargeable batteries.However,the commercialization of metal anodes is hampered by irregular dendrite growth,which severely deteriorates the safety and cyclability of metal anodes.Optimizing the electrolyte by nanostructured additives to regulate the metal deposition shows great potential since the electrochemically nonreactive feature endows the regulation function with good sustainability.In this manuscript,the fundamental dendrite formation models and key parameters for stabilizing metal anode are first discussed.The progress and functional mechanism of nanostructured additives for regulating the metal deposition are summarized in terms of regulatory model,i.e.,deposition-,adsorption-and dispersion-type.Finally,we also provide a detailed concluding outlook,pointing out the future trend of selecting new nanostructured additive candidates and elucidating synergistic effects and underlying mechanisms with the key attention being given to the assessments of practicality.