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When exposed to different relative humidities (RHs), the optical properties of atmospheric aerosols will change because of changes in the aerosol particle size and complex refractive index (RI), which will affect haze formation and global climate change. The potential contributions of ultrafine particles to the atmospheric optical characteristics and to haze spreading cannot be ignored because of their high particle number concentrations and strong diffusibility; measurement of the optical properties of wet ultrafine particles is thus highly important for environmental assessment. Therefore, a surface plasmon resonance microscopy with azimuthal rotation illumination (SPRM-ARI) system is designed to determine the RIs of single particle aerosols with diameters of less than 100 nm in the hygroscopic growth process. Measurements are taken using mixed single particles with different mass ratios. The RIs of mixed single aerosols at different RHs are retrieved by measuring the scattering light intensity using the SPRM-ARI system and almost all the RIs of the bicomponent particles with different mass ratios decrease with increasing water content under high RH conditions. Finally, for each of the bicomponent particles, the maximum standard deviations for the retrieved RI values are only 2.06×10

The hygroscopic growth of atmospheric aerosols plays an important role in regional radiation, cloud formation, and hence climate. Aerosol hygroscopic growth is often characterized by hygroscopic tandem differential mobility analyzers (HTDMAs), and Xie et al. (2020) recently demonstrated that hygroscopic growth measurements of a single particle are possible using a surface plasmon resonance microscope-azimuthal rotation illumination (SPRM-ARI). The hygroscopic properties of ambient aerosols are not uniform and often exhibit large relative humidity (RH) and size variabilities due to different chemical compositions and mixing states. To better understand the contribution of different aerosol components and establish a link between the apparent hygroscopic properties of single particles and bulk aerosols, we conduct combined hygroscopic growth measurements using a SPRM-ARI and an HTDMA as a case study to prove the concept (experimental information: 100–200 nm, during noontime on 28 September 2021 and 22 March 2022 in Hefei, China). According to the distinct hygroscopic growth behavior from single-particle probing using a SPRM-ARI, the individual particles can be classified into three categories defined as non-hygroscopic (NH), less hygroscopic (LH), and more hygroscopic (MH). The mean growth factor (GF) of the three categories can be utilized to reproduce the GF distribution obtained from the HTDMA measurement. The chemical compositions of individual particles from the three categories are identified to be organic carbon (OC), soot (mainly elemental carbon), fly ash, and secondary aerosols (mainly OC and sulfate), using scanning electron microscopy (SEM) with an energy-dispersive spectrometer (EDS). The coupled SPRM–HTDMA measurement suggests a size-dependent variation of aerosol chemical components, i.e., an increase of OC fraction with increasing particle sizes, which agrees reasonably well with the chemical compositions from collected aerosol samples. This likely links the hygroscopic properties of individual particles to their bulk hygroscopic growth and chemical composition.

The hygroscopic growth of atmospheric aerosols plays an important role in regional radiation, cloud formation and hence climate. Aerosol hygroscopic growth is often characterized by humidified tandem differential mobility analyzers (HTDMA), and Xie et al. (2020) recently demonstrated that hygroscopic growth measurements of single-particle are possible using a surface plasmon resonance microscope-azimuthal rotation illumination (SPRM-ARI). The hygroscopic properties of ambient aerosols are not uniform and often exhibit large RH and size variabilities, due to different chemical compositions and mixing states. To better understand the contribution of different aerosol components and establish the link between the apparent hygroscopic properties of bulk aerosols and single-particle, we conduct combined hygroscopic growth measurements of single-particle by a SPRM-ARI and bulk particles by an HTDMA. The atmospheric nanoparticles were grouped into four subgroups labeled as EC, fly ash, OC and AS+OC based on the energy dispersive spectroscope results (Experimental information: 100 nm~200 nm, at noon, September 28th, 2021 and March 22th, 2022 in Hefei China). The relationship between the chemical composition of a single nanoparticle in each subgroup and its hygroscopicity was characterized using SPRM-ARI. Then, the HTDMA data were shown to be fitted and reconstructed by the constitutive particle size distributions calculated by the SPRM-ARI measured GFs (growth factor), and the percentage of four subgroups in atmospheric particles could also be found through the fitting. Based on the test results, we found the OC content of AS+OC nanoparticles increased with the increase of particle size, and the OC condensation may play a promoting role in the particle growth process. Lastly, this fitting reconstruction method has a good correlation with the quantitative results of membrane sampling, and can be used for reference to analyze the contribution of particle hygroscopicity and the growth mechanism of nanoparticle.

Monitoring system is widely used to detect the environment parameters such as temperature, humidity and position information in cold chain logistic, modern agriculture, hospital and so on. Poor position precision, high communication cost, high packet loss rate are the main problems in current monitoring system. To solve these problems, the paper presents a new monitoring system based on Narrow Band Internet of Things (NB-IoT) and BeiDou system/Global System Position (BDS/GPS) dual-mode positioning. Considering the position precision, a dual-mode positioning circuit based on at6558 is designed, and the calculation formula of the positioning information of the monitored target has been derived. Subsequently, a communication network based on wh-nb75-ba NB-IoT module is designed after compared with the LoRa technology. According to the characteristics of high time correlation of sensor data, an adaptive optimal zero suppression (AOZS) compression algorithm is proposed to improve the efficiency of data transmission. Experiments prove the feasibility and effectiveness of the system from the aspects of measurement accuracy, positioning accuracy and communication performance. The temperature and humidity error are less than 1 °C and 5% RH respectively with the selected sensor chips. The position error is decided by several factors, including the number of satellites used for positioning, the monitored target moving speed and NB-IoT module lifetime period. When the monitored target is stationary, the positioning error is about 2 m, which is less than that of the single GPS or BDS mode. When the monitored target moves, the position error will increase. But the error is still less than that of the single GPS or BDS mode. Then the AOZS compression algorithm is used in actually experiment. The compression ratio (CR) of it is about 10% when the data amount increasing. In addition, the packet loss rate test experiment proves the high reliability of the proposed system.

Human metapneumovirus (HMPV) plays an important role in acute respiratory tract infections (ARTIs), especially in children. We investigated the epidemiology of HMPV associated with ARTIs among pediatric inpatients and identified HMPV genetic variations in Qingdao, China, from January 2018 to June 2019. HMPV-positive samples were identified from throat swabs by multiplex real-time reverse transcriptase polymerase chain reaction (RT-PCR). The G gene sequences of HMPV were obtained, followed by phylogenetic analysis. As a result, 71 out of 1051 (6.76%) patients were HMPV positive, and the HMPV-positive rate in children under 5 years of age was three times higher than that in those aged 5-17 years. The epidemic season of HMPV was in spring, with a peak mainly in March. Thirty-two nucleotide sequences of the HMPV G gene successfully obtained were clustered into three genotypes, A2c (25/32, 78.13%), B1 (3/32, 9.38%) and B2 (4/32, 12.50%). In addition, 76% (19/25) of A2c viruses were identified as the emerging A2c

Importance There is accumulating evidence that intermittent fasting (IF) is connected to improved health condition and longevity time-restricted feeding (TRF) is the most recognized and extensively studied model of IF. Objective To investigate the underlying mechanism of pleiotropic benefits of IF and hint the most advantageous feeding pattern for humans. Evidence review We searched MEDLINE, EMBASE, Cochrane Library and Google Scholar by 2020 April for publications on IF or TRF and their mechanisms. Studies include animal models and human cohorts. Findings One important mechanism is that IF allows certain period of fasting time, in which our bodies activate pathways of repair and rejuvenation. Moreover, the advantages of IF, especially TRF over total caloric restriction (CR) provided bases for various animal and human studies which suggested that the feeding-fasting rhythm stimulates the fluctuation of our gut microbiota and a series of subsequent molecular alterations, which in turn restored a healthier circadian clock that resembled our inherent clock formed throughout millions of years of homo sapiens history. Conclusions and relevance for reviews Complete understanding of the mechanism leading to the beneficial effects of IF paves the way for tailored dietary regimen to combat a wide range of diseases and ill health conditions.

Aerosol particle hygroscopicity is an important factor in visibility reduction, cloud formation, radiation forcing, and the global climate. The high number concentration of nanoparticles (defined a...

Text detection is a key technique and plays an important role in computer vision applications, but efficient and precise text detection is still challenging. In this paper, an efficient scene text detection scheme is proposed based on the Progressive Scale Expansion Network (PSENet). A Mixed Pooling Module (MPM) is designed to effectively capture the dependence of text information at different distances, where different pooling operations are employed to better extract information of text shape. The backbone network is optimized by combining two extensions of the Residual Network (ResNet), i.e., ResNeXt and Res2Net, to enhance feature extraction effectiveness. Experimental results show that the precision of our scheme is improved more than by 5% compared with the original PSENet.

We detected human metapneumovirus (HMPV) in 72 (7.1%) of 1,021 patients hospitalized with severe acute respiratory infection in Luohe, China, during 2017-2019. We detected HMPV most frequently in young children and less often in adults. HMPV genotype A2c variants 111 nt and 180 nt duplications predominated, demonstrating their continuing geographic spread.

Time-restricted feeding (TRF), a feasible form of intermittent fasting, has been proven to benefit metabolic health in animal models and humans. TRF restricts the daily feeding window to 3 to 12 h for eating ad libitum, with fasting for the rest of the day. To our knowledge, specific guidance on the appropriate time period for eating during TRF has not yet been promoted. Therefore, the aim of the present review was to summarize the current literature on the effects of TRF with different eating windows in humans and compare their effects on metabolic health-related markers. Early TRF (which restricts food intake during the early period of the day) and delayed TRF (which restricts food intake during the later period of the day) studies have shown that both TRF regimens improve metabolic health in terms of reducing energy intake, decreasing body weight, improving insulin sensitivity, reducing blood pressure, and reducing oxidative stress. Differences between the consequences of early and delayed TRF were found, including differences in changes in blood lipid factors. These preliminary findings may help to provide guidance for choosing suitable eating windows during TRF. Future studies with rigorous designs and direct comparisons between the effects of TRF regimens with different eating windows on metabolic health markers are still needed.

Purpose Ovarian cancer is the leading cause of gynecologic cancer-related death worldwide. Early diagnosis of ovarian cancer can significantly improve patient prognosis. Hence, there is an urgent need to identify key diagnostic and prognostic biomarkers specific for ovarian cancer. Because high-grade serous ovarian cancer (HGSOC) is the most common type of ovarian cancer and accounts for the majority of deaths, we identified potential biomarkers for the early diagnosis and prognosis of HGSOC. Methods Six datasets (GSE14001, GSE18520, GSE26712, GSE27651, GSE40595, and GSE54388) were downloaded from the Gene Expression Omnibus database for analysis. Differentially expressed genes (DEGs) between HGSOC and normal ovarian surface epithelium samples were screened via integrated analysis. Hub genes were identified by analyzing protein-protein interaction (PPI) network data. The online Kaplan-Meier plotter was utilized to evaluate the prognostic roles of these hub genes. The expression of these hub genes was confirmed with Oncomine datasets and validated by quantitative real-time PCR and Western blotting. Results A total of 103 DEGs in patients with HGSOC-28 upregulated genes and 75 downregulated genes-were successfully screened. Enrichment analyses revealed that the upregulated genes were enriched in cell division and cell proliferation and that the downregulated genes mainly participated in the Wnt signaling pathway and various metabolic processes. Ten hub genes were associated with HGSOC pathogenesis. Seven overexpressed hub genes were partitioned into module 1 of the PPI network, which was enriched in the cell cycle and DNA replication pathways. Survival analysis revealed that MELK, CEP55 and KDR expression levels were significantly correlated with the overall survival of HGSOC patients (P < 0.05). The RNA and protein expression levels of these hub genes were validated experimentally. Conclusion Based on an integrated analysis, we propose the further investigation of MELK, CEP55 and KDR as promising diagnostic and prognostic biomarkers of HGSOC.

Skin fibrosis is mainly characterized by excessive collagen deposition. Studies have recently identified a number of flavonoids with variable structures that have the potency of inhibiting collagen synthesis and thus attenuating organ fibrosis. In this study, we found that flavones with 5, 7, 3′, 4′ hydroxy substitution reduced collagen expression most efficiently. Among those flavones, luteolin, quercetin, and myricetin were selected for follow-up. In vivo, the three compounds ameliorated skin fibrosis and reduced collagen deposition. Further analysis showed the compounds had significant inhibition on the proliferation, activation and contractile ability of dermal fibroblasts in vitro and in vivo. More importantly, we revealed that luteolin, quercetin, and myricetin selectively downregulated the phosphorylation of Smad2/3 in TGF-β/Smads signaling via binding to activin receptor-like kinase 5 (ALK5) and impairing its catalytic activity. We also found flavones with 5, 7, 3′, 4′ hydroxy substitution showed stronger affinity with ALK5 compared with other flavonoids. Herein, we identified at least in part the underlying molecular basis as well as the critical structures that contribute to the antifibrotic bioactivity of flavones, which might benefit drug design and modification.

Wei River is the largest tributary of the Yellow River, and in recent decades, water resource has changed significantly. Identifying the characteristics and influencing factors of streamflow change in Wei River is needed for development of effective management strategies and economic development for the region and entire Yellow River basin. The analyzations were based on streamflow records from 1957 to 2018 at five hydrological stations as well as precipitation and air temperature data from 22 meteorological stations. Mann-Kendall method and Pettitt test were used to analyze trends and transition years of hydrometeorological variables. Double mass curves (DMC) were used to quantify the impact of climate changes and anthropogenic activities on streamflow change. The results showed that: the annual average streamflow decreased significantly in the upper reaches (URWR), middle reaches (MRWR) of the main Wei River, Jing River Basin (JRB), Beiluo River Basin (BLRB) as well as the whole Wei River Basin (WWRB). There were transition years existed in these reaches and concentrated in 1990s. The annual precipitation showed a significant downward trend in the MRWR, LRWR, BLRB and WWRB (P

The supersaturated condensation of atmospheric aerosol is important in the study of mechanisms of cloud condensation and even heavy air pollution. The existing technology cannot realize accurate dynamic control of wide range supersaturation, so it is difficult to study condensation growth characteristics of nanoparticles through different levels of supersaturation. Here, a supersaturated condensation growth measurement system with three-stage microscope pipes was developed. The resolution of supersaturated condensation system is 0.14, within the range of 0.92 to 2.33 after calibration. Stabilization time is only about 80 s for saturation range 0.92–1.01, which helps to control saturation rapidly, and the control deviation of saturation is no more than 0.06. Measurement of different supersaturated condensation growth control conditions showed that, the particle size increased significantly compared with hygroscopic growth at high humidity. For single-component particles, the increase in size increased to a similar size at the same saturation, with a difference within 7.4%. The increase in size for ammonium sulfate (AS) increased by 13.4–30.2% relative to that of glucose. For the mixed-component, the increase in size decreased about 15.9–25.0% with the increase of the glucose. Because the glucose coating on the surface of AS have hindered particle growth. This also shows that atmospheric ultrafine particles, especially inorganic salt particles, will rapidly grow into larger particles under supersaturated conditions such as increased environmental humidity, thus having some impact on environmental pollution and climate change.

Time-restricted feeding (TRF) improves metabolic health. Both early TRF (eTRF, food intake restricted to the early part of the day) and mid-day TRF (mTRF, food intake restricted to the middle of the day) have been shown to have metabolic benefits. However, the two regimens have yet to be thoroughly compared. We conducted a five-week randomized trial to compare the effects of the two TRF regimens in healthy individuals without obesity (ChiCTR2000029797). The trial has completed. Ninety participants were randomized to eTRF (n=30), mTRF (n=30), or control groups (n=30) using a computer-based random-number generator. Eighty-two participants completed the entire five-week trial and were analyzed (28 in eTRF, 26 in mTRF, 28 in control groups). The primary outcome was the change in insulin resistance. Researchers who assessed the outcomes were blinded to group assignment, but participants and care givers were not. Here we show that eTRF was more effective than mTRF at improving insulin sensitivity. Furthermore, eTRF, but not mTRF, improved fasting glucose, reduced total body mass and adiposity, ameliorated inflammation, and increased gut microbial diversity. No serious adverse events were reported during the trial. In conclusion, eTRF showed greater benefits for insulin resistance and related metabolic parameters compared with mTRF. Clinical Trial Registration URL: http://www.chictr.org.cn/showproj.aspx?proj=49406 .

ObjectivePancreatic ductal adenocarcinoma (PDAC) shows a remarkable predilection for liver metastasis. Pro-oncogenic secretome delivery and trafficking via exosomes are crucial for pre-metastatic microenvironment formation and metastasis. This study aimed to explore the underlying mechanisms of how PDAC-derived exosomes (Pex) modulate the liver microenvironment and promote metastasis.DesignC57BL/6 mice were ‘educated’ by tail vein Pex injection. The intrasplenic injection liver metastasis and PDAC orthotopic transplantation models were used to evaluate liver metastasis. Stable cell lines CD44v6 (CD44 variant isoform 6) or C1QBP (complement C1q binding protein) knockdown or overexpression was established using lentivirus transfection or gateway systems. A total of 142 patients with PDAC in Huashan Hospital were retrospectively enrolled. Prognosis and liver metastasis were predicted using Kaplan-Meier survival curves and logistic regression models.ResultsPex tail vein injection induced the deposition of liver fibrotic extracellular matrix, which promoted PDAC liver metastasis. Specifically, the exosomal CD44v6/C1QBP complex was delivered to the plasma membrane of hepatic satellite cells (HSCs), leading to phosphorylation of insulin-like growth factor 1 signalling molecules, which resulted in HSC activation and liver fibrosis. Expression of Pex CD44v6 and C1QBP in PDAC patients with liver metastasis was significantly higher than in PDAC patients without liver metastasis, and simultaneous high expression of exosomal CD44v6 and C1QBP correlated with a worse prognosis and a higher risk of postoperative PDAC liver metastasis.ConclusionThe Pex-derived CD44v6/C1QBP complex is essential for the formation of a fibrotic liver microenvironment and PDAC liver metastasis. Highly expressed exosomal CD44v6 and C1QBP are promising biomarkers for predicting prognosis and liver metastasis in patients with PDAC.

The growth in aerosol particles caused by water uptake during increasing ambient relative humidity alters the physical and chemical properties of aerosols, which then affects public health, atmospheric chemistry, and the Earth’s climate. The temporal resolution and sensitivity of current techniques are not sufficient to measure the growth dynamics of single aerosol nanoparticles. Additionally, the specific time required for phase transition from solid to aqueous has not been measured. Here, we describe a label-free photonic microscope that uses the Bloch surface waves as the illumination source for imaging and sensing to provide real-time measurements of the hygroscopic growth dynamics of a single aerosol (diameter

Background: Time-restricted feeding, also known as intermittent fasting, can confer various beneficial effects, especially protecting against obesity, and related metabolic disorders, but little is known about the underlying mechanisms. Therefore, the present study aims to investigate the effects of time-restricted feeding on the circadian rhythm of gut microbiota and hepatic metabolism.Methods: Eight-week-old male Kunming mice received either a normal diet ad libitum, a high-fat diet ad libitum, or a high-fat diet restricted to an 8-h temporal window per day for an experimental period of 8 weeks. Weight gain and calorie intake were measured weekly. Serum metabolites, hepatic sections and lipid metabolites, gut microbiota, and the hepatic expression of Per1, Cry1, Bmal1, SIRT1, SREBP, and PPARα were measured at the end of the experimental period. The composition of gut microbiota and the expression of hepatic genes were compared between four timepoints.Results: Mice that received a time-restricted high-fat diet had less weight gain, milder liver steatosis, and lower hepatic levels of triglycerides than mice that received a high-fat diet ad libitum (p < 0.05). The numbers of Bacteroidetes and Firmicutes differed between mice that received a time-restricted high-fat diet and mice that received a high-fat diet ad libitum (p < 0.05). Mice fed a time-restricted high-fat diet showed distinct circadian rhythms of hepatic expression of SIRT1, SREBP, and PPARα compared with mice fed a normal diet ad libitum, as well as the circadian rhythm of the abundance of Bacteroidetes and Firmicutes.Conclusions: Time-restricted feeding is associated with better metabolic conditions, perhaps owing to alterations in gut microbiota and the circadian pattern of molecules related to hepatic lipid metabolism, which were first to report.

Objective To compare the efficacy and safety between drug-coated devices (DCDs) and bypass surgery with saphenous vein graft (BSV) in femoropopliteal arterial occlusive disease. Methods A Bayesian network meta-analysis and indirect comparison were performed. Randomized controlled trials of BSV, bypass surgery with prosthetic graft, bare metal stents, endoluminal bypass (covered stent), percutaneous transluminal angioplasty, and DCDs treating femoropopliteal arterial occlusive disease were collected. The primary end point was target lesion revascularization/target vessel revascularization, and secondary end points were all-cause mortality, limb salvage, and early complications (PROSPERO registry number: CRD42019136530). Results Forty-two trials and 6867 patients were included. The comparison of DCDs and BSV revealed no significant difference in the 1-year target lesion revascularization/target vessel revascularization (DCDs vs BSV: odds ratio [OR], 0.60; 95% credible interval [CrI], 0.16-2.39). Total early complications from BSV were significantly higher than those from DCDs (DCDs vs BSV: OR, 0.14; 95% CrI, 0.05-0.45), and the main complications of BSV were not death related. There was also no significant difference in systemic early complications (DCDs vs BSV: OR, 0.19; 95% CrI, 0.00-7.82) and 1-year amputation rate (DCDs vs BSV: OR, 2.81; 95% CrI, 0.16-89.53). The 30-day (DCDs vs BSV: OR, 0.38; 95% CrI, 0.00-110.46), 1-year (DCDs vs BSV: OR, 0.96; 95% CrI, 0.24-3.29), 2-year (DCDs vs BSV: OR, 1.60; 95% CrI, 0.64-4.95), and 5-year all-cause mortality rates (DCDs vs BSV: OR, 2.05; 95% CrI, 0.92-4.39) showed no significant differences between DCDs and BSV, although there was a noticeable tendency toward significant results of a higher 5-year mortality rate. Conclusions There is no significant difference between DCDs and BSV in short-term efficacy or short- and long-term mortality. Despite traditional BSV remaining the gold standard, DCDs provide a reasonable alternative therapy. In addition, the DCDs have a lower short-term morbidity associated with the procedure at the cost of the possible risk of higher long-term mortality. Clinical trials with more validity are required for a direct comparison between BSV and DCDs.

A dry-ambient aerosol size spectrometer (DAASS) was previously developed to conduct measurements of aerosol water content at ambient relative humidity (RH) conditions. However, the RH difference of ambient RH and DAASS conditioning humidity (i.e., 10–20%, particularly when the DAASS operated at a high ambient RH) may introduce uncertainties in estimation of aerosol water content. In this study, we present a prototype of an RH-controlled DAASS. By employing an active RH controlling method, we resolve the discrepancy between the ambient RH and the DAASS conditioning RH, therefore extending the accurate measurement of aerosol water content to a wide RH range. The performance of this RH-controlled DAASS was characterized by both the laboratory evaluation and a 10-day field deployment. Results showed that the DAASS conditioning RH agreed well with the ambient RH (R2 of 0.993 when ambient RH up to 90%), with an average RH offset of less than 1.5%. The fraction of aerosol-bound water in the total ambient aerosol volume was ~10% under RHs below 50% and increased to ~50% when the ambient RH reached above 85%.

Quantitatively assessing the characteristics of river streamflow variation and conducting research on attribution identification are the basis for formulating climate-change response strategies and rational use of water resources. Based on the daily streamflow data of the Zhuangtou Hydrological Station in 1970–2018, this paper analyzes the streamflow changes in the Beiluo River Basin and studies the impact of climate change and anthropogenic activities on the streamflow in this basin. A non-parametric Mann–Kendall test and Pettitt’s test were used to determine the trend and detect abrupt changes of streamflow and baseflow. The method based on precipitation and potential evapotranspiration, as well as the double-mass curve of precipitation–streamflow, was established to evaluate the impact of climate change and non-climate factors on annual streamflow. The results reveal a statistically significant downward trend (p = 0.01) in both annual streamflow and baseflow, with the abrupt point year in 1994 and 1988, respectively. When comparing to a modest declining trend in annual average precipitation, we see that the temperature showed a significant upward trend (p = 0.01), whose abrupt point year was 1996. Under the policy of returning farmland to forest, land-use analysis shows that the area of farmland had decreased by 222.4 km2, of which 31.4% was mainly converted into the forestland. By the end of 2015, the area of forestland had increased by 123.4 km2, which has largely caused streamflow decrease. For the method based on precipitation and potential evapotranspiration, climate change contributed 43.7% of the annual streamflow change, and human activities (mainly refers to LUCC) contributed 56.3%. For the DMC of precipitation–streamflow, the precipitation contributed 9.4%, and non-precipitation factors (mainly refers to human activities) contributed 90.6%, and human activities played a more vital part in driving streamflow reduction in different decades, with a contribution rate of more than 70%. This study is of great practical significance to the planning, management, development and utilization of water resources in basins.

In order to realize accurate dynamic control of supersaturation and to study condensation growth characteristics of nanoparticles through different levels of supersaturation, a series of parametric analyses and systematic comparisons between two-stage and three-stage operating temperature designs were simulated with COMSOL Multiphysics. The simulation results showed that the three-stage operating temperature did not change peak supersaturation compared with two operating temperatures, and the three-stage operating temperature was superior in decreasing the amount of water vapor and the temperature, thus lowering particle loss and variation in detection and collection. The peak supersaturation level increased by 0.3 as the flow rate increased from 0.6 to 2.0 L/min, but the supersaturation peak moved from 0.0027 z0 to 0.08 z0 (i.e., the growth time and the final size decreased by 40%). Peak supersaturation increased as the temperature difference increased or the temperature difference window was shifting left, and minimum activation size decreased. Shifting the 70°C temperature difference window from 9°C, 79°C–1°C, 71°C for the condenser and initiator temperatures resulted in peak supersaturation in the centerline being above 5.8, and the activation size changed as low as 1 nm. Experiments with flow rates varying by a factor of 2.5 (from 0.6 to 1.5 L/min) resulted in a final size decrease of 43% (from 3.2 to 1.8 μm), and experimental results of outlet particle size distributions were equivalent with theoretical analysis as the operating temperature was changed.

Low temperature NH

Significant contribution of ultrafine particles in the atmosphere to the cloud condensation nuclei and precipitation has been evidenced. The correlation between the condensation growth and chemical composition of particles is essential in the atmospheric studies. To reduce the lower detection limit of ATOFMS (currently at 200 nm), a water-based particle size amplifier, consisted of a tubing inner-lined with an expanded polytetrafluoroethylene layer and temperature-controlled in three sections, was designed, and its amplification performance was evaluated. With the use of the particle size amplifier, the peaks of Na and Cl in the mass spectra of 50 nm NaCl particles were obviously observed. Further, 50 nm NaCl/Dicarboxylic Acid (DA) particles were generated and characterized by ATOFMS with the amplifier and the sizes of ultrafine particles after the amplifier was measured by an Aerodynamic Particle Spectrometer (APS). It is found that the Cl/Na ratio in 50 nm NaCl + DA particles was negatively correlated with the DA concentration and positively correlated with the acidity coefficient of the DAs, i.e., the high DA mass fraction in particles and low the acidity coefficient of DAs results in strong heterogeneous reaction in the generation of these particles. The amplified sizes of NaCl + DA nanoparticles was also greatly influenced by the degree of the reaction involved. The Cl/Na ratio of NaCl + DA particles was found to have positive correlation with the amplified size of particles.

Epidemiology survey indicated that cigarette smoking is a risk factor of diabetes. However, the precise mechanisms remain to be clarified. In this study, we found that smoking caused metabolic malfunctions on pancreas and liver in experimental animal model. These were indicated by hyperglycemia, increased serum hemoglobin A1c level and decreased insulin secretion, inhibition of liver glycogen synthase (LGS), and hepatic glycogen synthesis. Mechanistic studies revealed that all these alterations were caused by the inflammatory reaction and reactive oxygen species (ROS) induced by the smoking. Melatonin treatment significantly preserved the functions of both pancreas and liver by reducing β cell apoptosis, CD68‐cell infiltration, ROS production, and caspase‐3 expression. The siRNA‐knockdown model identified that the protective effects of melatonin were mediated by melatonin receptor‐2 (MT2). This study uncovered potentially underlying mechanisms related to the association between smoking and diabetes. In addition, it is, for first time, to report that melatonin effectively protects against smoking‐induced glucose metabolic alterations and the signal transduction pathway of melatonin is mainly mediated by its MT2 receptor. These observations provide solid evidence for the clinically use of melatonin to reduce smoking‐related diabetes, and the therapeutic regimens are absent currently.

One design method of infrared remote control is introduced which is based on field programmable gate arrays FPGA devices. The paper gives a construction method for infrared remote system. The system uses PT2248 as a transmitter, MIM-R1AA38kHz integrated infrared receiver demodulator as a receiver. Then it explains how to use EDA technology top-down design approach to achieve infrared remote control decoder chip, decipher, key in, number reveal and alarm function of briefing on etc. The paper also details in features and performance of ALTERA DEII platform, at the same time use the Cyclone II ?of EP2C35F672C6N to realize the whole system on DE2 board with the EDA tools.

Most active noise control algorithms require the identification of the secondary path model. This will give rise to increased complexity and other potential problems in the real system. In this paper, we proposed an improved ANC algorithm requiring no secondary path model by introducing a phase compensating mechanism based on the strict positive real (SPR)property of the filtered-x LMS algorithm. Compared with the existing methods, our algorithm can automatically find the right phase compensating amount of secondary path and will always converge regardless of the frequency of reference signal.