Pollution Characteristics and Source Apportionment of Black Carbon Aerosols during Spring in Beijing.

Black carbon (BC) aerosols are important for absorbing aerosols, affecting global climate change and regional air quality, and potentially harming human health. From March to May 2023, we investigated black carbon aerosol levels and air pollution in Beijing. Employing methods such as linear regression, Potential Source Contribution Function (PSCF) and Concentration-Weighted Trajectory (CWT), we analyzed the characteristics and sources of black carbon aerosols in the region. Results indicate that the light absorption coefficients of BC and BrC decrease with increasing wavelength, with BrC accounting for less than 40% at 370 nm. Daily variations in BC and PM2.5 concentrations exhibit similar trends, peaking in March, and BC displays a distinct bimodal hourly concentration structure during this period. Aethalometer model results suggest that liquid fuel combustion contributes significantly to black carbon (1.08 ± 0.71 µg·m-3), surpassing the contribution from solid fuel combustion (0.31 ± 0.2 µg·m-3). Furthermore, the significant positive correlation between BC and CO suggests that BC emissions in Beijing predominantly result from liquid fuel combustion. Potential source area analysis indicates that air masses of spring in Beijing mainly originate from the northwest (40.93%), while potential source areas for BC are predominantly distributed in the Beijing-Tianjin-Hebei region, as well as parts of the Shandong, Shanxi and Henan provinces. Moreover, this study reveals that dust processes during spring in Beijing have a limited impact on black carbon concentrations. This study's findings support controlling pollution in Beijing and improving regional air quality.

Insecticide Susceptibility and KDR Mutations in Aedes Albopictus Collected from Seven Districts of Guangyuan city, Northern Sichuan, China.

The Asian tiger mosquito, Aedes albopictus, is an important vector of chikungunya, dengue, yellow fever, and Zika viruses. Vector control remains an important means for the prevention and control of vector-borne diseases. The development of insecticide resistance has become a serious threat to the efficacy of insecticide-based control programs. To understand the resistance status and the underlying genetic mechanism in mosquitoes in Guangyuan City of Sichuan Province, China, we investigated the susceptibility of Ae. albopictus to four commonly used insecticides. We found that all the examined populations were susceptible to malathion and propoxur. However, Ae. albopictus populations in Guangyuan showed a possible resistance to the two tested pyrethroids (beta-cypermethrin and deltamethrin). Notably, phenotypic resistance to deltamethrin was detected in 2 of the 7 populations. The potential of resistance to pyrethroids was confirmed by the presence of knockdown resistance (kdr) related mutations in the voltage-gated sodium channel. Four kdr mutations (V1016G, I1532T, F1534L, and F1534S) were identified to be present alone or in combination, and their distribution displayed significant spatial heterogeneity. These findings are helpful for making evidence-based mosquito control strategies and highlight the need to regularly monitor the dynamics of pyrethroid resistance in this city.

Study on the Fingerprint and Atmospheric Activity of Volatile Organic Compounds from Typical Industrial Emissions.

China is prone to severe surface ozone pollution in summer, so it is very important to understand the source of volatile organic compounds (VOCs) to control ozone formation. In this work, the emission characteristics of 91 VOC components from the plastic products industry, packaging and printing industries, printing ink industry, furniture manufacturing and vehicle manufacturing industries were studied. The results show that there are significant differences between these sources, and for the plastic products industry, alkanes (48%) are the most abundant VOCs. The main emission species in the packaging and printing industry are OVOCs (36%) and alkanes (34%). The proportion of OVOCs in the printing ink (73%) and furniture manufacturing industries (49%) is dominated by VOC emissions; aromatic hydrocarbons (33%), alkanes (33%), and OVOCs (17%) are the main emission species in the vehicle manufacturing industry. At the same time, the ozone generation potential (OFP) and secondary organic aerosol formation potential (SOA) of anthropogenic VOC emissions were evaluated, and the top 10 contributors to OFP and SOA were identified. Toluene, o-xylene, and m-xylene had a significant tendency to form OFP or SOA. Then, a health risk assessment of VOC components was carried out. These data can supplement the existing VOC emission characteristics of anthropogenic emissions, thus enriching the research progress of VOC emission sources.

p-Synephrine exhibits anti-adipogenic activity by activating the Akt/GSK3ß signaling pathway in 3T3-L1 adipocytes.

This work aimed to investigate the effects of p-synephrine on the differentiation of adipocyte and explore the underlying mechanism. We found that p-synephrine suppressed the 3T3-L1 cell adipogenesis by reducing the expression level of CCAAT/enhancer-binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PPARγ), which subsequently led to a reduction in the fatty acid-binding protein 4 (aP2) expression. p-Synephrine treatment markedly activated the protein kinase B (PKB/Akt) pathway and sequentially inhibited glycogen synthase kinase 3ß (GSK3ß) activity. Inhibition of GSK3ß activity by LiCl was found to partially ameliorate the above-mentioned effects. All these data suggested that p-synephrine exhibited the anti-adipogenic effects via the regulation of Akt signaling pathway and the suppression of adipogenesis-related proteins. PRACTICAL APPLICATIONS: Citrus aurantium often uses as herbal or dietary supplement in various countries around the world, including in Seville, Spain and South Africa. In traditional Chinese herbs, it is referred to as "Fructus aurantii immaturus," "Zhi shi," or "Zhi ke," and has been used for hundreds of years for various digestive problems. Its primary protoalkaloid, p-synephrine, exhibited lipolytic effects and energy expenditure, which has rapidly replaced ephedrine as an "ephedra-free" alternative dietary supplement. The current study firstly demonstrated the anti-adipogenic effects of p-synephrine in 3T3-L1 preadipocytes, which was due to the regulation of Akt signaling pathway and the subsequent suppression of adipogenesis-related proteins. The present study may offer invaluable opinions into the mechanisms of body weight/fat-losing activities of p-synephrine in theory, and scientific experimental evidence on dietary supplement in practice. p-Synephrine could be utilized for the preventive and therapeutic uses against metabolic syndrome.

Paeonol ameliorates monosodium urate-induced arthritis in rats through inhibiting nuclear factor-κB-mediated proinflammatory cytokine production.

Moutan Cortex has been widely used to treat various types of arthritis in traditional Chinese medicine. Paeonol is isolated as an active ingredient from Moutan Cortex. However, the effect and potential mechanism of paeonol on gouty arthritis have not been evaluated. In this study, rats were treated intragastrically with paeonol for consecutive 7 days. On Day 5, rats were intra-articularly injected with monosodium urate (MSU) crystals in the ankle joints to induce MSU-induced arthritis (MIA). Paw volume was detected at various time points. Gait score was measured at 24 hr after MSU crystal injection. Ankle joints were collected for evaluation of histological score and expression of proinflammatory cytokines using hematoxylin and eosin staining and immunohistochemistry staining, respectively. Nuclear level of nuclear factor (NF)-κBp65 in synovial tissues was analyzed by western blot assay. NF-κB DNA-binding activity was measured by enzyme linked immunosorbent assay. Paeonol markedly lowered the paw volume, gait score, and histological score in MIA rats. Mechanistically, paeonol markedly reduced the expression of TNF-α, IL-1ß, and IL-6 in synovial tissues of MIA rats. In addition, the elevated level of p65 in nucleus and NF-κB DNA-binding activity in synovial tissues of MIA rats were reduced significantly by paeonol treatment. These findings suggest that paeonol exerts anti-inflammatory effect in MIA rats through inhibiting expression of proinflammatory cytokines and NF-κB activation.

Flower extracts from Paeonia decomposita and Paeonia ostii inhibit melanin synthesis via cAMP-CREB-associated melanogenesis signaling pathways in murine B16 melanoma cells.

This investigation seeks to identify the effects of the EtOAc fractions of different flower parts of Paeonia decomposita (Pd) and Paeonia ostii (Po) on melanogenesis and their mechanisms of action in B16 melanoma cells. Cell viability assay showed that Pd-1, Po-1 (the petals of Pd or Po), Pd-3 and Po-3 (the stamens of Pd or Po) at 25 µg/ml produced lower toxic activities in B16 cells. Pd-1 and Po-1 extracts considerably reduced the melanin content and inhibited tyrosinase and DOPA oxidase activity. Moreover, Pd-1 and Po-1 down-regulated the expressions of MC1R, MITF, TRP-1, TRP-2, and tyrosinase. These extracts also reduce cAMP levels and inhibited the phosphorylation of CREB, which might be due to the presence of high concentrations of phenolic compounds and flavonoids. Our results suggested that Pd-1 and Po-1 are able to modulate the cAMP-CREB signaling pathway and down-regulate the melanogenesis-related proteins resulting in the observed anti-melanogenic effects. PRACTICAL APPLICATIONS: In China, the flower of Paeonia is often consumed as a dietary supplement and as an additive in skin whitening products. In November 2013, the National Health and Family Planning Commission of the People's Republic of China has approved the flower of Paeonia ostii as a novel food resource. The current study firstly demonstrated that the effects of EtOAc fractions of the petals of Paeonia decomposita (Pd) and Paeonia ostii (Po) considerably reduced the melanin content in B16 cells, which is due to the modulation of the cAMP-CREB signaling pathway followed by the down-regulation of melanogenesis-related proteins. Pd and Po extracts, as natural tyrosinase inhibitors, may serve as good candidates in food additives, cosmetic materials, or even in treating hyperpigmentation diseases.

Geniposide Suppresses Hepatic Glucose Production via AMPK in HepG2 Cells.

Geniposide is one of the main compounds in Gardenia jasminoides ELLIS and has many pharmacological activities, but its anti-hyperglycemic activity has not yet been fully explored. This study was designed to determine, for the first time, how geniposide from G. jasminoides regulates hepatic glucose production, and the underlying mechanisms. During in vitro study, we found the inhibitory effect of geniposide on the hepatic glucose production is partly through AMP-activated protein kinase (AMPK) activation in HepG2 cells. Geniposide significantly inhibited hepatic glucose production in a dose-dependent manner. AMPK, acetyl coenzyme A synthetase (ACC) and forkhead box class O1 (FoxO1) phosphorylation were stimulated by different concentrations of geniposide. In addition, the enzyme activities of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) were all significantly suppressed. What is important is that these effects were partly reversed by (1) inhibition of AMPK activity by compound C, a selective AMPK inhibitor, and by (2) suppression of AMPKα expression by small interfering RNA (siRNA). In summary, geniposide potentially ameliorates hyperglycemia through inhibition of hepatic gluconeogenesis by modulation of the AMPK-FoxO1 signaling pathway. Geniposide or geniposide-containing medicinal plants could represent a promising therapeutic agent to prevent type 2 diabetes on gluconeogenesis.

Study on preparation method of Zanthoxylum bungeanum seeds kernel oil with zero trans-fatty acids.

The seed of Zanthoxylum bungeanum (Z. bungeanum) is a by-product of pepper production and rich in unsaturated fatty acid, cellulose, and protein. The seed oil obtained from traditional producing process by squeezing or extracting would be bad quality and could not be used as edible oil. In this paper, a new preparation method of Z. bungeanum seed kernel oil (ZSKO) was developed by comparing the advantages and disadvantages of alkali saponification-cold squeezing, alkali saponification-solvent extraction, and alkali saponification-supercritical fluid extraction with carbon dioxide (SFE-CO2). The results showed that the alkali saponification-cold squeezing could be the optimal preparation method of ZSKO, which contained the following steps: Z. bungeanum seed was pretreated by alkali saponification under the conditions of adding 10 %NaOH (w/w), solution temperature was 80 °C, and saponification reaction time was 45 min, and pretreated seed was separated by filtering, water washing, and overnight drying at 50 °C, then repeated squeezing was taken until no oil generated at 60 °C with 15 % moisture content, and ZSKO was attained finally using centrifuge. The produced ZSKO contained more than 90 % unsaturated fatty acids and no trans-fatty acids and be testified as a good edible oil with low-value level of acid and peroxide. It was demonstrated that the alkali saponification-cold squeezing process could be scaled up and applied to industrialized production of ZSKO.

[Spectral calibration of hyperspectral imager based on spectral absorption target].

Retrieval of center wavelength and bandwidth is a key step for quantitative analysis of hyperspectral data. The present paper proposes a spectral calibration method of hyperspectral imager, whose spectrum covers visible and near-infrared band, using spectral absorption target. Ground calibration experiment was designed for a hyperspectral imager with a bandwidth of 6 nm. Hyperspectral imager and ASD spectrometer measured the same spectral absorption target synchronously. Reflectance spectrum was derived from the different data set. Center wavelength and bandwidth were retrieved by matching the reflectance data from hyperspectral imager and ASD spectrometer. The experiment result shows that this method can be applied in spectral calibration of hyperspectral imagers to improve the quantitative studies on hyperspectral imagery.

[Improved extraction of solanesol from tobacco waste by enzymatic cell wall breaking].

To improve the extraction of solanesol from tobacco waste, we developed an enzymatic cell wall-breaking process with combined cellulase and ligninase. The effects of reaction time, temperature, pH and enzyme/substrate ratio were determined. The results show that the catalytic effect was better than either single enzyme when the ratio of cellulase to ligninase was 15:1 (U/U). Under the optimized conditions of 175 U/g (enzymes/substrate), tobacco to water 1:5 (W/W), temperature 40 degrees C and pH 6.0, the concentration of solanesol in the solution could reach 0.33 g/L after 8 h. And the average leaching rate reached 96.53% which was 1.68 times of the extraction methods of chemical reflux. It provides new way for the extraction of solanesol from tobacco waste, and worthwhile to be further explored.

[In-flight absolute radiometric calibration of UAV hyperspectral camera and its validation analysis].

With the data in Urad Front Banner, Inner Mongolia on November 14th, 2010, hyper-spectral camera on UAV was calibrated adopting reflectance-based method. During the in-flight absolute radiometric calibration, 6 hyper-spectral radiometric gray-scale targets were arranged in the validation field. These targets' reflectances are 4.5%, 20%, 30%, 40%, 50% and 60% separately. To validate the calibration result, four extra hyper-spectral targets with sharp-edge spectrum were arranged to simulate the reflection and absorption peaks in natural objectives. With these peaks, the apparent radiance calculated by radiation transfer model and that calculated through calibration coefficients are much different. The result shows that in the first 15 bands (blue bands), errors are somewhat huge due to the noises of equipment. In the rest bands with quite even spectrum, the errors are small, most of which are less than 10%. For those bands with sharp changes in spectral curves, the errors are quite considerable, varying from 10% to 25%.

[Activating effect of citrus flavonoids on neuromedin U2 receptor and analysis on siRNA interference].

OBJECTIVE: To screen out active substances on Neuromedin U2 receptor (NMU2R) by using stable NMU2R cell lines and negative cell lines and analyzing siRNA interference. METHOD: NMU2R cells were used to observe the activating effect of nine nine citrus flavonoids on NMU2R cell. Afterwards, false-positive interference of citrus flavonoids that showed higher activating effect was eliminated by using negative cells and analyzing the efficiency of siRNA interference. RESULT: Hesperidin and nobiletin contained in citrus flavonoids were found to effectively activate NMU2R. The efficacy, EC50 and potency values of hesperidin were 4.688, 318.970 micromol x L(-1) and 200.933 micromol x L(-1), while the efficacy, EC50 and potency values of nobiletin were 4.758, 5.832 micromol x L(-1) and 3.124 micromol x L(-). CONCLUSION: Hesperidin and nobiletin contained in citrus flavonoids can activate NMU2R. Nobiletin shows such a low EC50 that it has medicinal value.

Visible light responsive N-F-codoped TiO2 photocatalysts for the degradation of 4-chlorophenol.

N-F-codoped TiO2 (NFTO) photocatalysts were synthesized by a simple sol-gel process with tetrabutyl titanate (Ti(OBu)4) as the precursor of TiO2 and ammonium fluoride (NH4F) as the source of N and F. The synthesized photocatalysts were investigated by Xray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) and photodegradation reaction tests of 4-chlorophenol under visible light irradiation to understand the relationship between the structure of NFTO catalyst and corresponding photocatalytic activity. The crystal phase and particle size of catalysts were found to be largely affected by the calcination temperature. In addition, N-F-codoping could inhibit phase transition of TiO2 from anatase to rutile. The presence of N and F atoms in the lattice of TiO2 is responsible for the visible light catalytic activity. In UV-Vis DRS tests, the spectrum of NFTO exhibited red shift compared with Degussa P25 and the band gap was reduced to around 2.92 eV. Under optimal calcination temperature and dopant concentration conditions, the NFTO photocatalyst exhibited the highest activity in the photodegradation reaction tests of 4-chlorophenol under visible light irradiation with a degradation rate of 75.84%. Besides, the 5-recycle test showed that NFTO photocatalyst could be reused and its activity kept stable under visible light irradiation.

[Effect and mechanism of total flavonoids of orange peel on rat adjuvant arthritis].

OBJECTIVE: To investigate the effect of the total flavonoids of orange peel (TFO) against adjuvant arthritis (AA) and the underlying mechanism. METHOD: AA model was induced in male Wistar (correction of SD) rats by immunization with Freund's complete adjuvant Pad thickness was assayed by caliper. Pathological impairment of ankle joint was analysised by hematoxylin and eosin (H&E) staining. Levels of tumor necrosis factor (TNF)-alpha, Interleukin (IL)-1beta and prostaglandin (PG) E2 in serum was detected by radioimmunoassay method. Cyclooxygenase (COX)-2 expression in synovium tissues was measured by Western blot assay. RESULT: The 75 mg x kg(-1) and 150 mg x kg(-1) TFO treatment obviously decreased the pad thickness and improve the pathological impairment of ankle joint of AA rats. In addition, abnormal elevation of TNF-alpha, IL-1beta and PGE2 in serum and COX-2 expression in synovium tissues of AA rats were markedly repressed by TFO treatment. CONCLUSION: TFO can inhibit the development of AA in rats, and the mechanism were likely due to depressing inflammatory mediators production.

[High throughput screening method of identifying D5 receptor agonist from Chinese herbs].

D5 receptor is a subtype of dopamine D1-like receptor, and it plays a functional role in many neurological disorders. Some natural compounds from Chinese herbs, which were shown to have the property as that of receptor agonist, might provide a rich source in search of new candidates for therapeutic use. For exploring this possibility, we developed a cell-based high throughput (HTS) D5 receptor assay to screen the herb-based natural compound library established in our centre. The D5 receptor plasmid (hD5R/pcDNA3.1) and reporter gene plasmid (4 x CRE/TK/Luci/pGL3) were co-transfected into HEK293 cell line. After G418 being selected, the monoclonal cell lines bearing hD5R and the reporter gene were established and used for agonist screening. To optimize the assay condition, the effects of some factors such as cell number per well, incubation time, and the doses of SKF38393 (a potent selective partial D1-like agonist) were examined by using forskolin, a positive compound for cAMP response element. The best condition for this HTS assay included: the cell number at 5 x 10(4)/mL, the dose of forskolin at 5-20 micromol/L, the dose of SKF38393 at 100 nmol/L-100 micromol/L, and the agonist incubation time at 6 -8 h. Thereafter, water extracts from more than 200 Chinese herbs in our library were screened and three of these water extracts showed positive activity, with higher or similar activity as SKF38393. In conclusion, we have established a cell-based HTS assay for D5 receptor agonist screening, and by use of this HTS assay, 3 Chinese herbs maybe contain components exhibiting D5 receptor agonist property. This work provides an alternative vision of how to use herb medicines and a way to develop potential drugs for treatment of neurological disorders.