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A novel fiber-tip micro flowmeter based on optofluidic microcavity filled with silver nanoparticles solutions (SNS) is proposed. CW fiber laser was used to heat SNS that can emit heat obviously due to the excellent optic-thermo effect. The heat generated by the silver nanoparticles would be taken away as the microfluidic flows over the fiber microcavity until thermal balance is established under different velocity. The effective refractive index (RI) of the SNS changed followed by temperature of the thermal balance. The dips of the Fabry–Perot interference spectrum shift and the flow velocity can be demodulated. Moreover, the sensor can measure the flow rate with a high sensitivity due to the superior thermal conductivity and specific heat capacity of sidewalls. The max flow rate sensitivity can reach 1.5 nm/(μL/s) in the large range of 0–5 μL/s with a detection limitation (DL) of 0.08 μL/s. The Micron scale probe-type flowmeter has strong robustness and can be used to measure flow rate in tiny space. The heating medium also has an excellent biological compatibility and is not contact with the fluidics directly. As such, we believe that the proposed fiber-tip micro flowmeter has great application potentials in haematology, oil prospecting, ocean dynamics and drug research.

To observe corneal nerve fibers and densitometry after small incision lenticule extraction (SMILE), femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and laser-assisted subepithelial keratomileusis (LASEK) for high myopia.This is a prospective, cross-sectional research study. Patients with high myopia (equivalent spherical lens: -6.00 and -11.00D) who underwent laser corneal refractive surgery were divided into three groups: SMILE, FS-LASIK and LASEK. Scheimpflug imaging of corneal nerves in five areas was observed by confocal microscopy before and 6, 12 months after surgery. Corneal densitometry was measured by Pentacam anterior segment analysis system.Overall, 59 patients were enrolled. The nerve density in the central area did not recover to the preoperative level in three groups until 12 months. The density and length of corneal nerves in central and lower area were better in the SMILE group 6 months postoperatively (p = 0.01), while nerve density did not differ significantly among three groups 12 months postoperatively (p = 0.18). Nerve fibers in central and temporal region were wider in LASEK than that in other two groups at 6- and 12-month follow-up. Corneal densitometry in the central 6 mm diameter was significantly higher in the LASEK group compared with other two groups 6 months postoperatively (p = 0.04). Twelve months postoperatively, corneal densitometry in range of all zone was lower in SMILE than in FS-LASIK and LASEK (p = 0.01, 0.03, 0.04).Compared with FS-LASIK and LASEK, SMILE-treated eyes with high myopia had certain advantages in nerve density, length and nerve connection way and had better corneal transparency after operation.

Secondary organic aerosol (SOA) makes a sizable contribution to fine-particulate-matter (PM2.5) pollution, especially during high-PM episodes. Past studies of SOA evolution at the episode scale mainly rely on measurements of bulk SOA mass, with few studies probing individual SOA molecular tracers. In this study, we continuously monitored (at a bi-hourly resolution) SOA tracers specific to a few common volatile organic compound (VOC) precursors at a suburban site in Hong Kong for a 4-month period from the end of August to December 2020. The SOA molecules include tracers for SOA derived from biomass burning (BB) emissions, monoaromatics, naphthalene/methylnaphthalenes, and three biogenic VOCs (isoprene, monoterpene, and sesquiterpene). Generally, the SOA tracers showed regional characteristics for both anthropogenic and biogenic SOA as well as for the BB-derived SOA. This work focused on the seasonal variation and evolution characteristics of SOA tracers during 11 city-wide PM2.5 episodes, which are defined as periods with PM2.5 concentrations exceeding 35 µg m−3 at 3 or more of the 15 general air quality monitoring stations cross the city. Mass increment ratios (MIR), calculated as the ratio of the mass concentration prior to an episode to that during an episode, were examined for individual species during each episode. During most episodes, the SOA tracer concentrations were enhanced (i.e. MIR >1), and the maximum MIR values were in the range of 5.5–11.0 for SOA tracers of different precursors. Episodes on summer and fall days showed notably larger MIR values than those falling on winter days, indicating the higher importance of SOA to the formation of summer/fall PM2.5 episodes. Simultaneous monitoring of six tracers for isoprene SOA revealed the dominance of the low-NOx pathway in forming isoprene SOA in our study region. The multiple monoterpene SOA products suggested fresher SOA in winter, evidenced by the increased presence of the early-generation products. Thus, the current study has shown by example the precursor-specific SOA chemical evolution characteristics during PM2.5 episodes in different seasons. This study also suggests the necessity to apply high-time-resolution organic marker measurement at multiple sites in order to fully capture the spatial heterogeneity of haze pollution at the city scale.

The development of high-efficiency multi-wire submerged arc welding technology in bridge engineering has been limited due to the high mechanical performance standards required. In this paper, weld metal was obtained by welding at three different high heat inputs with the laboratory-developed high-efficiency submerged arc welding wire for bridges. The effect of changing different high heat inputs on the microstructure and impact toughness of high efficiency submerged arc weld metal was systematically investigated by cutting and Charpy V-notch impact tests at −40 °C, using optical microscopy, scanning electron microscopy, energy-dispersive electron spectroscopy, electron backscatter diffraction, and transmission electron microscopy to characterize and analyze. With the increase in heat input from 50 kJ/cm to 100 kJ/cm, the impact absorption energy decreased significantly from 130 J to 38 J. The number of inclusions in the weld metal significantly decreased and the size increased, which led to a significant decrease in the number of inclusions that effectively promote acicular ferrite nucleation, further leading to a decrease in the proportion of acicular ferrite in the weld metal. At the same time, the microstructure of the weld metal was significantly coarsened, the percentage of high-angle grain boundaries was decreased, and the size of martensite/austenite constituents was significantly increased monotonically. The crack initiation energy was reduced by the coarsened martensite/austenite constituents and inclusions, which produced larger local stress concentrations, and the crack propagation was easier due to the coarsened microstructure and lower critical stress for crack instability propagation. The martensite/austenite constituents and inclusions in large sizes worked together to cause premature cleavage fracture of the impact specimen, which significantly deteriorated the impact toughness. The heat input should not exceed 75 kJ/cm for high-efficiency submerged arc welding wires for bridges.

According to the requirements of the "Quick Guide for Drug Evaluation and Selection in Chinese Medical Institutions", this health technology assessment provides an evidence-based basis for drug selection and rational clinical use of glucagon-like peptide-1 receptor agonist drugs in medical institutions.We consult the drug instructions, clinical treatment guidelines and search relevant documents in databases such as China national knowledge infrastructure, Wanfang, PubMed, and government websites such as National Medical Products Administration, Food and Drug Administration, European Medicines Agency, and Pharmaceuticals and Medical Devices Agency to collect and sort out the relevant information of the indications, pharmacological effects, guideline recommendations, drug prices and other information of glucagon-like peptide-1 receptor agonists, using a percentile system systematically evaluate the five dimensions of glucagon-like peptide-1 receptor agonists in terms of pharmaceutical properties, efficacy, safety, economy, and other attributes.The final scores of the evaluation results from high to low are semaglutide (71.00 points), dulaglutide (68.75 points), liraglutide (67.50 points), exenatide (67.00 points), lixisenatide (63.50 points), polyethylene glycol loxenatide (58.00 points) and benaglutide (49.00 points).In clinical practice, semaglutide and dulaglutide are the top two drugs that can be used as recommended drugs. This health technology assessment can provide an evidence-based basis for hospital selection and rational use of glucagon-like peptide-1 receptor agonists. Clinicians can rationally choose and use drugs according to the patient's conditions and needs.

Jinjian Li,1,* Kun Yang,2,* Xinghui Pan,1 Hui Peng,1 Chenting Hou,1 Jie Xiao,1 Qing Wang1 1Ophthalmology, Affiliated Hospital of Qingdao University, Qingdao, 266500, People’s Republic of China; 2Medical Research Center, Affiliated Hospital of Qingdao University, Qingdao, 266500, People’s Republic of China*These authors contributed equally to this workCorrespondence: Qing Wang, Ophthalmology, Affiliated Hospital of Qingdao University, 16 Jiangsu Road, Qingdao, 266500, People’s Republic of China, Tel +86 17853290636, Fax +86 532 82911747, Email wangqing6836@sina.comPurpose: The biological role and mechanism of long noncoding RNA (lncRNA) myocardial infarction-associated transcript (MIAT) in dry eye remain to be illustrated. Pyroptosis is a noticeable form of inflammatory activation, which is characteristic of gasdermin D (GSDMD)-driven cell death. The present study was designed to explore the role of MIAT in pyroptosis and apoptosis induced by hyperosmolarity stress (HS) in human corneal epithelial cells (HCECs).Methods: HCECs were cultured in 70– 120 mM hyperosmotic medium for 24 h to create a dry eye model in vitro. The level of the pyroptosis marker GSDMD was measured, and the cell inflammatory response was evaluated by detecting IL-1β and IL-18 levels. Exogenous caspase-1 inhibitor Ac-YVAD-CHO was used. The pyroptosis in HCECs was examined by caspase-1 activity, immunofluorescent staining, and Western blotting. Flow cytometry was performed to test the apoptosis rate of HCECs. Cell migration and proliferation were detected. The expression of the lncRNA MIAT in HCECs was detected by quantitative real-time PCR. MIAT was knocked down by small interfering RNA (siRNA) transfection. The effects of caspase-1 inhibition on pyroptosis, apoptosis, migration, and proliferation were observed.Results: HS promoted pyroptosis in HCECs by elevating caspase-1, GSDMD, and the active cleavage of GSDMD (N-terminal domain, N-GSDMD), and increased the release of IL-1β, IL-18, LDH and the rate of apoptosis, with reduced cell migration. These changes were prevented by the inhibition of caspase-1. The expression of MIAT was significantly increased in HCECs exposed to a hyperosmotic medium. Silencing MIAT increased the expression of GSDMD, caspase-1, and inflammatory chemokines IL-1β and IL-18, and promoted apoptosis while inhibiting migration and proliferation in HCECs.Conclusion: The lncRNA MIAT is involved in HS-induced pyroptosis and apoptosis and the inflammatory response of HCECs and provides a new understanding of the pathogenesis of dry eye.Keywords: myocardial infarction-associated transcript, dry eye, pyroptosis, apoptosis

The traffic management system holds immense importance due to its significant impact on human living standards. With the advent of advanced technologies such as natural language processing and autonomous vehicles, this study proposes a novel cooperative traffic management system based on collection auctions at an isolated unsignalized intersection, taking into account the users’ preferences for passing the intersection while being subject to their social credits. Once vehicles enter the vehicle-to-infrastructure communication zone, drivers provide the intersection control center with their bidding information, which reflects their urgency for right-of-way. According to the traffic and biding information, the vehicles’ passing sequence is optimized by the control center, in order to maximize the drivers’ average satisfaction. To demonstrate the effectiveness of the proposed system, a series of simulation experiments were conducted under varying traffic volumes. The simulation results were then compared with several other traffic control systems from the literature. It was shown that the proposed algorithm demonstrates superior performance in terms of computational time, traffic delay, and drivers’ personal satisfaction.

As the theoretical upper bound of evapotranspiration (ET) or water use by ecosystems, potential ET (PET) has always been widely used as a variable linking a variety of disciplines, such as climatology, ecology, hydrology, and agronomy. However, substantial uncertainties exist in the current PET methods (e.g., empiric models and single-layer models) and datasets, because of unrealistic configurations of land surface and unreasonable parameterizations. Therefore, this study comprehensively considered interspecific differences in various vegetation-related parameters (e.g., plant stomatal resistance and CO2 effects on stomatal resistance) to calibrate and parametrize the Shuttleworth-Wallace (SW) model for forests, shrubland, grassland and cropland. We derived the parameters using identified daily ET observations with no water stress (i.e., PET) at 96 eddy covariance (EC) sites across the globe. Model validations suggest that the calibrated model could be transferable from known observations to any location. Based on four popular meteorological datasets, relatively realistic canopy height and time-varying land use/land cover and Leaf Area Index, we generated a global 5 km ensemble mean monthly PET dataset that includes two components of potential transpiration (PT) and soil evaporation (PE) for the 1982–2015 time period. Using this new dataset, the climatological characteristics of PET partitioning and the spatio-temporal changes in PET, PE and PT were investigated. The global mean annual PET was 1200 mm with PT/PET of 40 % and PE/PET of 60 %, and moreover controlled by PT and PE over 43 % and 57 % of the globe, respectively. Globally, the annual PET and PT significantly (phttps://doi.org/10.11888/Terre.tpdc.300193 (Sun et al., 2023).

Studying the variation in the boundary position of the Asian summer monsoon in the Tibetan Plateau (TP) region and its potential drivers is important for understanding the climate in this region. Three sets of mean monthly precipitation data from 1980 to 2019 were sourced from the Global Precipitation Climatology Centre, the Climate Research Unit, and China Meteorological Information Service Centre. Several indicators that represent the Asian summer monsoon boundary (ASMB) were selected to compare their applicability to the TP region and elucidate the changes in the location of the ASMB in the TP over the last four decades. The results showed that the ASMB in the TP region extends in a southwest-northeast direction, with a clear north-south variation. It reaches as far north as the Kunlun Mountains and as far south as the Himalayas. The largest amplitude in spatial fluctuation occurs in the middle of the TP, and the smallest amplitude occurs at both ends of the region. A “small-large-small” fluctuation pattern was observed from west to east. The water vapor mainly originates from the South Asian region. The South Asian summer monsoon can move the ASMB position northward, whereas the westerly wind moves the ASMB position southward. Variation in the ASMB in the TP region is closely associated with the South Asian monsoon and westerly wind.

Aiming at the comparison and optimization of comprehensive evaluation methods, this paper proposes an optimization strategy of comprehensive evaluation method and constructs a relative excellence measure of the comprehensive evaluation method based on the deviation of rating value and Spearman grade correlation coefficient. On the basis of the relative excellence measure, combined with the compatibility test, the optimization strategy of the comprehensive evaluation method is given to realize the optimization of the comprehensive evaluation method. Finally, the feasibility of this strategy is verified by a case.

The short and scare record limits to understand the history of the hydroclimate change in east-central China. In this study, we developed a 225-year tree-ring width chronology (STD) for Chinese pine originating from the Shiren Mountain in Henan Province, east-central China. We analysed the correlation between the STD and different climatic factors and then reconstructed the May–June moisture variation, which is one of the longest moisture variation reconstruction based on tree-ring width in this region. Further, the results of the spatial analysis between our reconstruction and actual moisture variation revealed that our reconstruction is representative of large-scale May–June self-calibrating Palmer Drought Severity Index (scPDSI) in east-central China. Additionally, the reconstruction showed five relatively dry and five relatively wet epochs over the past 225 years. It also showed that the moisture variation in the study area is similar to those corresponding to other nearby sites and could be validated by historical documents; these findings demonstrate the reliability of our reconstruction back in time. Furthermore, we detected the reason for the coherent May–June moisture change in east-central China. It showed that the actual scPDSI showed significantly positive correlations with concurrent precipitation. Additionally, regression analyses showed that precipitation is largely determined by the frontal system, which is also responsible for the coherent May–June moisture pattern observed in east-central China. In addition, the result of spectral analysis and correlation patterns of the reconstructed scPDSI with global sea surface temperatures indicated that the El Nino-Southern Oscillations might be the forcing mechanism for regional moisture variability.

The two-dimensional MAX phases with compositional diversity are promising functional materials for electrochemical energy storage. Herein, we report the facile preparation of the Cr2GeC MAX phase from oxides/C precursors by the molten salt electrolysis method at a moderate temperature of 700°C. The electrosynthesis mechanism has been systematically investigated, and the results show that the synthesis of the Cr2GeC MAX phase involves electro-separation and in situ alloying processes. The as-prepared Cr2GeC MAX phase with a typical layered structure shows the uniform morphology of nanoparticles. As a proof of concept, Cr2GeC nanoparticles are investigated as anode materials for lithium-ion batteries, which deliver a good capacity of 177.4 mAh g−1 at 0.2 C and excellent cycling performance. The lithium-storage mechanism of the Cr2GeC MAX phase has been discussed based on density functional theory (DFT) calculations. This study may provide important support and complement to the tailored electrosynthesis of MAX phases toward high-performance energy storage applications.

The half-bridge converter series Y-connection microgrid (HCSY-MG) is a new type of series microgrid. In order to reduce the harmonic content in HCSY-MG grid-connected current and at the same time simplify the parameter design process of the LCL filter, this study proposed an LCL filter parameter design method based on an improved particle swarm optimization-least squares support vector machine (PSO-LSSVM) by analyzing the harmonic characteristics of the HCSY-MG grid-connected current. In addition, to enhance the convergence speed of PSO-LSSVM, the inertia factor during its parameters’ update is made to adjust adaptively according to the direction of two consecutive parameter changes to constitute an improved PSO-LSSVM. Through simulation and comparative analysis, it is demonstrated that the improved PSO-LSSVM can enhance the convergence speed; the proposed filter parameter design method can effectively reduce the harmonic content in the HCSY-MG grid-connected current and is simpler and more comprehensive than the existing design method.

Cerebral ischemia is one of the major global health problems, but the treatment for it is currently very limited. A tissue plasminogen activator, the only drug effective in the treatment of cerebral ischemia, has a narrow time window and strict contraindications, resulting in only a small percentage of patients benefiting from it. Apigenin (APG) is a natural phytoestrogen flavonoid, widely found in vegetables and fruits including parsley, Chinese celery and chamomile. APG has shown good neuroprotective effects in animal models of many neurological diseases. For the first time, we report a review of the neuroprotective effects of APG in cerebral ischemia. We came to the conclusion that APG can exert various protective effects against cerebral ischemia, including anti-oxidative stress, anti-inflammatory, anti-autophagic, anti-apoptotic and other neuroprotective effects. Moreover, APG has shown a highly promising ability to prevent cerebral ischemia in terms of regulating blood glucose, blood pressure, lipids and gut microbes. The aspect that is of particular importance is the potential of APG to prevent cerebral ischemia in postmenopausal women, who are more likely to suffer from cerebral ischemia and have a much higher mortality rate than men of the same age. This review has provided evidence on the therapeutic and preventive effects of APG in cerebral ischemia, suggesting the potential values of APG as a candidate medication in future.

Background and objective Epimedii has long been used as a traditional medicine in Asia for the treatment of various common diseases, including Alzheimer's disease, cancer, erectile dysfunction, and stroke. Studies have reported the ameliorative effects of Icariside II (ICS II), a major metabolite of Epimedii, on acute ischemic stroke (AIS) in animal models. Based on network pharmacology, molecular docking, and molecular dynamics (MD) simulations, we conducted a systematic review to evaluate the effects and neuroprotective mechanisms of ICS II on AIS. Methods First, we have searched 6 databases using studies with ICS II treatment on AIS animal models to explore the efficacy of ICS II on AIS in preclinical studies. The literature retrieval time ended on March 8, 2022 (Systematic Review Registration ID: CRD42022306291). There were no restrictions on the language of the search strategy. Systematic review follows the Patient, Intervention, Comparison and Outcome (PICO) methodology and framework. SYCLE's RoB tool was used to evaluate the the risk of bias. In network pharmacology, AIS-related genes were identified and the target-pathway network was constructed. Then, these targets were used in the enrichments of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and gene ontology (GO). Molecular docking and MD simulation were finally employed between ICS II and the potential target genes. Results Twelve publications were included describing outcomes of 1993 animals. The literature details, animal strains, induction models, doses administered, duration of administration, and outcome measures were extracted from the 12 included studies. ICS II has a good protective effect against AIS. Most of the studies in this systematic review had the appropriate methodological quality, but some did not clearly state the controlling for bias of potential study. Network pharmacology identified 246 targets with SRC, CTNNB1, HSP90AA1, MAPK1, and RELA as the core target proteins. Besides, 215 potential pathways of ICS II were identified, such as PI3K-Akt, MAPK, and cGMP-PKG signaling pathway. GO enrichment analysis showed that ICS II was significantly enriched in subsequent regulation such as MAPK cascade. Molecular docking and MD simulations showed that ICS II can closely bind with important targets. Conclusions ICS II is a promising drug in the treatment of AIS. However, this systematic review reveals key knowledge gaps (i.e., the protective role of ICS II in women) that ICS II must address before it can be used for the treatment of human AIS. Our study shows that ICS II plays a protective role in AIS through multi-target and multi-pathway characteristics, providing ideas for the development of drugs for the treatment of AIS.

In the context of global warming, meteorological disasters occur more frequently in various regions which exert increasing influences on human life. Snow disasters are some of the natural disasters that most seriously affect the development of husbandry on the Qinghai–Tibetan Plateau (QTP), so it is necessary to explore their spatio-temporal variations and perform comprehensive risk assessment. Based on the daily snow depth data set in China, obtained by inversion of satellite remote sensing data, the spatio-temporal variation characteristics of snow disasters on the QTP from 1980 to 2019 were studied. The regional difference in the comprehensive risks of snow disasters for the husbandry on the QTP was evaluated from four perspectives, i.e., the risk of hazard factors, sensitivity of hazard-inducing environments, vulnerability of hazard-affected bodies, and disaster prevention and mitigation capacity. The farmer and pastoralist well-being (FPWB) index in five typical regions was constructed to discuss the possible influences of snow disasters on the FPWB since the 21st century. Results show that, in the last 40 years, the frequency, duration, average snow depth, and grade of snow disasters on the QTP all exhibited significant interannual and interdecadal variabilities, and they also displayed a declining long-term trend. The comprehensive risk of snow disasters for the husbandry on the QTP is low in the north while high in the south. The high-risk zone accounts for 1.54% of the total and is mainly located in Kashgar City in the north-western end of the QTP; the sub-high-risk and medium-risk zones are mainly found in the south of the plateau and are distributed in a tripole pattern, separately covering 15.96% and 16.32% of the total area of the plateau; the north of the plateau mainly belongs to low-risk and sub-low-risk zones, which separately account for 43.06% and 23.12% of the total area of the plateau. Since the beginning of the 21st century, the FPWB in five typical regions, namely, Kashgar (I), Shigatse (II), Nagqu (III), Qamdo (IV), and Yushu (V), has been increasing, while the risk of snow disasters has gradually decreased. Every 1% decrease in the risk of snow disasters corresponded to 0.186%, 0.768%, 0.378%, 0.109%, and 0.03% increases in the FPWB index in the five regions. Snow disasters affect FPWB mainly by directly or indirectly damaging material resources (livestock inventories and meat production) and social and financial resources.

BackgroundTo compare the postoperative safety, efficacy, predictability, visual quality and biomechanics after implantation of Artisan vs. Artiflex phakic intraocular lenses (PIOLs).MethodsPubmed, Embase, Cochrane Library were conducted up from January 2000 to February 2020. Comparative clinical studies reporting in accordance with the eligibility criteria were included in this meta-analysis. The pooled weighted mean differences (WMDs) and odds ratios (ORs) with corresponding 95% confidence intervals were calculated.ResultsComparative trials with myopia patients were selected in this review. The pooled WMD and OR estimates statistical significance in terms of postoperative best corrected visual acuity (BCVA), efficacy, postoperative spherical equivalence (SE), predictability, contrast sensitivity and mean intraocular higher-order aberrations (HOA) (mm) for a 6-mm pupil, manifesting that Artiflex PIOL showed evident beneficial effect for correcting myopia compared to Artisan PIOL. There was no significant difference in the incidence of complications between the two groups.ConclusionBoth of two techniques were safe and effective for myopia and compared to Artisan PIOL, Artiflex PIOL had significant improvement in efficacy, predictability, contrast sensitivityand HOA, except safety and complications in the treatment of moderate to high myopia.

The event camera, a new bio-inspired vision sensor with low latency and high temporal resolution, has brought great potential and demonstrated a promising application in machine vision and artificial intelligence. Corner detection is a key step of object motion estimation and tracking. However, most existing event-based corner detectors, such as G-eHarris and Arc*, lead to a huge number of redundant or wrong corners, and cannot strike a balance between the accuracy and real-time performance, especially in complex scenes with high texture that require higher computational costs. To address these issues, we propose an asynchronous corner detection method: a double threshold filter with Sigmoid eHarris (DTFS-eHarris) and an asynchronous corner tracker. The main contributions are that a double threshold filter is designed to reduce the redundant events and the improved Sigmoid function is utilized to represent the Surface of Active Events (Sigmoid*-SAE). We selected four scenes—shapes, dynamic, poster and boxes—from the public event camera dataset DAVIS240C to compare with the existing state-of-the-art hybrid method; our method has shown more than a 10% reduction in false positive rate and a 5% and 20% improvement in accuracy and throughput, respectively. The evaluations indicate that DTFS-eHarris shows a significant improvement, especially in complex scenes. Thus, it is anticipated to enhance the real-time performance and feature detection accuracy for future robotic applications.

In the context of global warming, climate change in river headwater regions and its drivers have attracted increasing attention. In this study, tree-ring width (TRW) chronology was constructed using tree-ring samples of fir (Abies faxoniana) in Dadu River Basin in the central part of the western Sichuan Plateau, China. Correlation analysis with climatic factors implies that the radial growth of trees in the region is mainly limited by temperature and has the highest correlation with the mean minimum temperature in summer (June and July) (R = 0.602, p < 0.001). On this basis, the TRW chronology was adopted to reconstruct variations in the mean minimum temperatures in summer from 1733 to 2010 in the upper reaches of Dadu River. The reconstruction equation was stable and reliable and offered a variance explanation rate of 36.2% in the observed period (1962~2010). In the past 278 years, the region experienced nine warm periods and ten cold periods. The warmest and coldest years occurred in 2010 and 1798, respectively, with values of 13.6 °C and 11.0 °C. The reconstruction was highly spatiotemporally representative and verified by temperatures reconstructed using other tree-ring data in surrounding areas. A significant warming trend was found in the last few decades. Moreover, the multi-taper method (MTM) analysis indicated significant periodic changes in quasi-2-year and 21–35-year periods, for which the El Niño Southern Oscillation (ENSO) and the Pacific decadal oscillation (PDO) could be the key controlling factors.

Although many temperature time-series reconstructions, constructed on the basis of tree-ring widths, with lengths of centuries to millennia have been published for many parts of the southeastern Tibetan Plateau (SETP), field reconstruction has been unaddressed to date. Here, we present a tree-ring network comprising 53 chronologies (one δ13C chronology, one regional maximum latewood density chronology, and 51 width chronologies). Using the modified point-by-point reconstruction method, a temperature field consisting of data from 28 meteorological stations in the SETP over the past 200–500 y (the common period was from 1730 to 1998; the longest single period was from 1480 to 2002) was reconstructed. Principal component analysis and rotated principal component analysis results indicated that the reconstructed temperature field may be representative of spatial distribution characteristics. The temperature changes in the SETP were similar. The correlation coefficients between the reconstructed regional average temperature and each observed series were 0.44–0.83 (86% were greater than 0.6, and all the significance tests reported a level of 0.01). Temperature changes were mainly synchronous with those in the middle and low latitudes of the Northern Hemisphere. We then explored the influence of possible climatic forcing and found that the Indian Ocean Basin mode may be a principal factor controlling the interannual variations in the STEP summer temperatures.

Secondary organic aerosol (SOA) makes a sizable contribution to fine particulate matter (PM2.5) pollution, especially during episodic hours. Past studies of SOA evolution at episode-scale mainly rely on measurements of bulk SOA mass and few studies probe individual SOA molecular tracers. In this study, we continuously monitored at a bihourly resolution SOA tracers specific to a few common volatile organic compound (VOC) precursors at a suburban site in Hong Kong for four-month from the end of Aug. to Dec. 2020. The SOA molecules include tracers for SOA derived from biomass burning emissions, monoaromatics, naphthalene/methylnaphthalenes, and three biogenic VOCs (i.e., isoprene, monoterpene and sesquiterpene). Generally, the SOA tracers showed regional characteristics for both anthropogenic and biogenic SOA, as well as the biomass burning-derived SOA. This work focused on the seasonal variation and evolution characteristics of SOA tracers during eleven city-wide PM2.5 episodes, which are defined to be periods of PM2.5 exceeding 35 μg/m3 at three or more of the 15 general air quality monitoring stations cross the city. Mass increment ratios (MIR), calculated as the ratio of mass concentration between before and during an episode, were examined for individual species in each episode. During most episodes, the SOA tracers were enhanced in their concentrations (i.e., MIR > 1) and maximum MIR values were in the range of 5.5–11.0 for SOA tracers of different precursors. Episodes on summer and fall days showed notably larger MIR values than those falling on winter days, indicating a higher importance of SOA to formation of summer/fall PM2.5 episodes. Simultaneous monitoring of six tracers for isoprene SOA revealed the dominance of the low-NOx pathway in forming isoprene SOA in our study region. The multiple monoterpene SOA products suggested fresher SOA in winter, evidenced by an increased presence of the early generation products. The current study has shown by example the precursor-specific SOA chemical evolution characteristics during PM2.5 episodes in different seasons. This study also suggests the necessity to apply the high time resolution organic marker measurement at multiple sites to fully capture the spatial heterogeneity of the haze pollution at the city scale.

Aims: This article aimed to assess the changes of subfoveal choroidal thickness (SFCT) in different follow-up durations for myopic children under the treatment of orthokeratology and give a reference for further studies.Method: Relevant publications were comprehensively retrieved through different databases, such as PubMed, Web of Science, Cochrane Library and Chinese database of Wan Fang and Wei Pu. Retrieval time was from the inception to February 2022. Standardized mean difference (SMD) and 95% confidence interval (95% CI) were selected as the effect for calculating and analyzing the changes of choroidal thickness in myopic children with orthokeratology.Result: A total of eight articles of 371 Patients (371 eyes) met our inclusion criteria. During the first month of wearing orthokeratology, choroidal thickness dramatically increased by 21.09 μ m (95%CI: 25.64, 16.7; PConclusion: This meta-analysis demonstrated that in the first month with orthokeratology, choroidal thickness presented an obvious increase, after that it became stable or got a slightly rise for the longer following-up treatment.

Global warming has a significant impact on the ecosystem of the high-altitude areas of the Tibetan Plateau, such as land degradation and the rapid retreat of glaciers. It is important to understand the effects of global warming occurring over hundreds or thousands of years. However, the long-term reconstruction of temperature is still lacking for the region of Western Sichuan Plateau (WSP). In this study, we reconstructed summer (June–July) temperatures back to 1383 for the WSP region based on a significant positive correlation between the standard chronology and summer temperature. The reconstruction passed statistical tests and explained 55.4% of the climatic variance in the period for which data are available (1962 to 2005). There have been five periods with warm summers and five with cold summers during the past 623 years. Warm periods occurred in 1383–1445, 1525–1590, 1700–1724, 1825–1870, and 1930–1960, while relatively cold periods occurred in 1446–1524, 1591–1675, 1725–1824, 1900–1929, and 1961–1990. A comparison with observed data and regional temperature reconstruction series shows that the reconstruction has a high degree of consistency and is indicative and reliability. The spatial correlation was analyzed with Climatic Research Unit gridded data to detect the spatial representativeness of the reconstruction, confirming that the reconstruction has a strong regional temperature signal for the WSP. Furthermore, ensemble empirical mode decomposition indicates quasi-oscillations of 2.8–3.3 years, 6.4–8.3 years, 11.1–14.2 years, 25–38.4 years, 89 years, and 138 years in the reconstructed temperature time series during the past 623 years. El Niño Southern Oscillation cycles, solar activity, and Atlantic multi-decadal oscillation can potentially be the primary forcing factors. Meanwhile, the coordinated action of temperature-induced drought stress with a late growing season related to delayed snowmelt can potentially be attributed to the divergence problem (observed around 2005).

BackgroundT-cell lymphoproliferative disease (T-LPD), characterized by primary Epstein–Barr virus (EBV) infection and clonal proliferation of T cells, occurs both in systemic and non-lymphatic organs. However, isolated indolent EBV-positive T-LPD involving the central nervous system has not been reported.Case PresentationA 48-year-old male who complained of headache, blurred vision, and weakness of the left lower limb for 1 month was hospitalized in our department. Neither neurological deficit nor palpable lymphadenopathy had been found. Bone marrow and laboratory tests had shown no abnormality as well. Enhanced MRI demonstrated enhanced cotton-like lesions up to 20 mm in diameter located in the right frontal, temporal, parietal and left parietal, occipital lobes with perifocal edema. Neuronavigation-assisted mini-craniotomy was performed to achieve total excision of the right temporal superficial lesion and identify the diagnosis. Pathological and EBV analysis described the lesion as indolent EBV-positive T-cell lymphoproliferative disease of the central nervous system (CNS). Then, a therapeutic regimen including whole-brain irradiation, chemotherapy, prednisolone, and aciclovir was given. Serial radiological imaging showed no signal of recurrence at 5 months' follow-up.ConclusionPrimary indolent T-LPD in the central nervous system is quite rare, and it needs to be distinguished from aggressive cerebral T-cell lymphoma, metastatic tumors, and other CNS lesions.

We proposed a novel torsion sensor based on the Lyot filter with the twisted polarization-maintaining fiber (PMF) acting as the birefringence medium. Lyot filter is formed by two linear polarizers and a piece of PMF. Based on the high birefringence of the PMF, the output polarization rotates with a rate equal to the twisting rate applied on the PMF, and the sensor realizes a high sensitivity of 90.072 dB/rad. The proposed sensor also demonstrated a low strain sensitivity of 2 .32 × 1 0 - 6 rad/μɛ. On the other hand, based on the phase hits of the polarization interference, the wavelength sensitivity reaches 15.477 nm/rad. The monitoring range of the wavelength demodulation is complementary with the intensity demodulation in one cycle, making the valid sensing range of the proposed sensor expand. The proposed highly sensitive compact torsion sensor, with large sensing range and low crosstalk, has potential applications in many fields such as manufacturing industry, civil engineering, aerospace industry and modern smart structure monitoring.

Monitoring the properties of fluids in microfluidic chips often requires complex open-space optics technology and expensive equipment. In this work, we introduce dual-parameter optical sensors with fiber tips into the microfluidic chip. Multiple sensors were distributed in each channel of the chip, which enabled the real-time monitoring of the concentration and temperature of the microfluidics. The temperature sensitivity and glucose concentration sensitivity could reach 314 pm/°C and −0.678 dB/(g/L), respectively. The hemispherical probe hardly affected the microfluidic flow field. The integrated technology combined the optical fiber sensor with the microfluidic chip and was low cost with high performance. Therefore, we believe that the proposed microfluidic chip integrated with the optical sensor is beneficial for drug discovery, pathological research and material science investigation. The integrated technology has great application potential for micro total analysis systems (μ-TAS).

Secondary organic aerosols (SOA) constitute a large fraction of atmospheric aerosols, yet our knowledge of the formation and aging processes of SOA in megacities of China is still limited. In this work, the formation and aging processes of SOA in winter in Beijing was investigated using a high-resolution aerosol mass spectrometer (AMS) and an oxidation flow reactor (OFR). Our results showed that the OA enhancement from OH aging peaked at ∼3.9 equivalent days with an average enhancement of 0.9 (±0.3) μg m

One of the most serious and worsening problems in much of the world is traffic congestion, which represents an undoubted menace to the quality of urban life, including wasting of time, and environmental pollution. Therefore, this study proposes a new dynamic cooperative traffic control algorithm based on Vehicle-to-Infrastructure connections to solve this problem. The proposed model contains three parts. First of all, when each vehicle enters the communication zone, it sends its estimated range of arrival time to the control center in the intersection; then the optimal passing sequence is calculated in the control center by dynamically grouping the compatible trajectories with the respect of the related safety constraints; finally, each vehicle optimizes its appropriate speed profile based on the given optimal time and speed to enter the intersection, which is sent by the control center. Several simulation cases are executed for different traffic volumes, whose results prove that vehicles under the proposed algorithm can pass the intersection with less travel time compared with traditional traffic control methods and other algorithms. Therefore, the proposed method can reduce the time delay and improve traffic efficiency.

Inorganic nitrogen (IN) and organic nitrogen (ON) molecules constitute a significant part of atmospheric aerosol. Unlike IN, the total ON quantity remains largely unquantified due to a lack of a simple and direct measurement method. This analytical deficiency hinders the quantitative assessment of the various environmental and health effect impacts by aerosol ON. In this work, we developed an analyzer system that utilizes programmed thermal evolution of carbonaceous and nitrogenous aerosols and chemiluminescence detection coupled with the multivariate curve resolution data treatment to achieve simultaneous quantification of IN and ON. The system is capable of detecting IN and ON as low as 96 ng N per sample on a small filter aliquot (1 cm2) without any pretreatment. This method breakthrough opens the door to quantifying an important pool of aerosol N that was analytically inaccessible in the past and holds the promise to quantifying IN and ON in other environmental samples. As a demonstration, quantification of aerosol ON at an urban site in Hong Kong, China, in samples spanning over a year reveals ON constituting a significant fraction (9-52%) of the total aerosol nitrogen and having major source origins in both secondary formation and primary emissions.

In this study we presented a composite standard chronology, spanning 1635–2018 to reconstruct May–July moisture variation in north central China. Our reconstruction revealed four severe dry epochs and five pronounced wet epochs. Additionally, spatial correlation analysis of our reconstruction with the actual self-calibrating Palmer drought severity index showed that our reconstruction was representative of large-scale May–July moisture changes. Both the severe dry and pronounced wet epochs showed one-to-one correspondence with other reconstructions nearby during their common periods, which demonstrated the reliability of our reconstruction backwards in time. Spectral analysis showed that significant spectral peaks were found at 2.1–3.8 years, which fell within the overall bandwidth of the El Niño-Southern Oscillations (ENSO). The spatial correlation patterns between our reconstruction and sea surface temperature (SST) in the equatorial eastern Pacific further confirmed the link between regional moisture and ENSO, with warm-phase ENSO resulting in low moisture and vice-versa. However, this link was time-dependent during the past four centuries, and was modulated by different phases of SST in the tropical Indian Ocean. Additionally, significant peaks at 24.9–46.5 years and spatial correlation patterns indicated that the Pacific Decadal Oscillation and the North Atlantic Oscillation may be the possible forcing factors of regional moisture at lower frequencies.

A full analysis of 3-month Standardized Precipitation-Evapotranspiration index (SPEI-3) changes and attribution analyses are of significance for deeply understanding dryness/wetness evolutions and thus formulating specific measures to sustain regional development. In this study, we analyze monthly and annual SPEI-3 changes over Southwest China (SWC; including Sichuan (SC), Chongqing (CQ), Guizhou (GZ), Yunnan (YN), and west Guangxi (wGX)) during 1961–2012, using the SPEI model and routine meteorological measurements at 269 weather sites. For SWC and each subregion (excluding wGX), annual SPEI-3 during 1961–2012 tends to decrease, and drying is at most of months in January and September–December, but wetting is in February–August (excluding March for wGX). Additionally, more than 50% of sites show declined and increased SPEI-3 in January, April, June, and August–December and the remaining months, respectively. Except for wGX with dominant of ET0, annual SPEI-3 changes in SWC and other four subregions have dominant of precipitation. Spatially, annual SPEI-3 changes at 59% of sites are because of precipitation, generally located in southeast SC, south YN, CQ, GZ, and south and northeast wGX. Nevertheless, dominants at regional and site scales vary among months, e.g., SWC, SC, CQ, and GZ, having dominant of precipitation (ET0) during September–December (most of months during January–August), YN always with dominant of precipitation, and wGX with dominant of precipitation (ET0) in February–April and July–December (January, May, and June). Importantly, this study provides a reference for quantitatively evaluating spatiotemporal dryness/wetness variations with climate change, especially for regions with significant drying/wetting.

We propose a method for generating bottle-hollow (BH) beams by tailoring the polarization state of the incident field in a tightly focused system. An optical BH field can be generated in the vicinity of the focus by tailoring azimuthal and radial polarization indices of the incident field. Calculations show that the length and diameter are mainly affected by the radial polarization index. While for the azimuthal index, it affects the width of the hollow greatly. As a result, an all-optical controlled tunable BH beam is achieved. The generated BH beam may find application in optical tweezers.