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Heavy metal contamination induced by cigarette smoking is a critical issue in environmental pollution and human health risk. Although a number of investigations have been performed on the detection of heavy metals in cigarette tobacco, only very limited data have been reported for the determination of these metals in other parts of cigarettes. In this study, the contents of copper, cadmium, chromium, nickel and lead in cigarette tobacco, smoke, ash and butts were quantified using high-resolution continuum source graphite furnace atomic absorption spectrometry. The LODs for Cu, Cd, Cr, Ni and Pb were 0.010 μg L−1, 0.020 μg L−1, 0.025 μg L−1, 0.030 μg L−1 and 0.012 μg L−1, respectively. Twelve cigarette samples purchased from eleven popular brands in China were used for the heavy metal measurements. Microwave digestion was employed for the preparation of the cigarette tobacco, ash and butt samples. A smoke collection apparatus, which was designed to simulate human smoking behavior by alternating suction and pause intervals, was used to capture the heavy metals in smoke. The total amounts of the determined metals were observed to be the highest in ash (55.60 to 125.99 μg g−1), followed by tobacco (11.70 to 22.34 μg g−1) and butts (4.29 to 15.22 μg g−1), and were 0.67, 0.10, 0.14, 0.16 and 0.24 μg per cigarette for Cu, Cd, Cr, Ni and Pb, respectively, in smoke. The residual rates of the heavy metals in ash, smoke and butts were measured to estimate the distribution of each element after the cigarette tobacco was fully burnt. The results indicated that the majority of the heavy metals (41.1% to 68.7%) remained in ash, with 10.0% to 28.0% condensed in butts and 6.6% to 22.9% released into the mainstream smoke. Moreover, a high variance of the five metal contents was observed in different brands of cigarettes, which might be associated with the geographical origin of the tobacco plant, cigarette production procedure, and transportation and storage of the materials and products. This study provides a reliable method for the quantitation of heavy metals in different components of cigarettes, which will be beneficial to the prevention of heavy metal hazards and the reduction of human health risks through tobacco consumption.

The temperature distribution information plays an important role in industrial applications. Owing to the advantages such as non-intrusive sensing and low cost, the ultrasonic tomography (UT) is considered to be a promising method for temperature field visualization. The ultrasonic time-of-flight (TOF) measurement and the reconstruction algorithm are crucial for practical applications of the UT measurement. In this paper, a dual-threshold measurement method is proposed to ensure a high-quality TOF measurement. In view of the inaccurate nature of the reconstruction model and TOF data, a new reconstruction method that integrates the advantages of the Tikhonov regularization method and the least squares support vector machine (LSSVM) is proposed to improve the reconstruction quality. The experimental results were compared against thermocouple measurements and the results show that the temperature distribution can be reconstructed with the error of 1.3%, which validates the feasibility and effectiveness of the proposed Tikhonov-LSSVM reconstruction algorithm.

Water injection can compensate for pressure depletion of production. This paper firstly investigated into the equilibrium issue among water influx, water injection and production. Equilibrium principle was elaborated through deduction of equilibrium equation and presentation of equilibrium curves with an “equilibrium point”. Influences of artificial controllable factors (e.g. well ratio of injection to production and total well number) on equilibrium were particularly analyzed using field data. It was found that the influences were mainly reflected as the location move of equilibrium point with factor change. Then reservoir pressure maintenance level was especially introduced to reveal the variation law of liquid rate and oil rate with the rising of water cut. It was also found that, even if reservoir pressure kept constant, oil rate still inevitably declined. However, in the field, a stabilized oil rate was always pursued for development efficiency. Therefore, the equilibrium issue of stabilized oil production was studied deeply through probing into some effective measures to realize oil rate stability after the increase of water cut for the example reservoir. Successful example application indicated that the integrated approach was very practical and feasible, and hence could be used to the other similar reservoir.

In this paper, The binding of twelve 1,3-diazaheterocyclic compounds (1a-1 l) to the fat mass and obesity-associated (FTO) protein was investigated by fluorescence, UV-vis absorption spectroscopy and molecular modeling. Results indicated that the intrinsic fluorescence of FTO is quenched by the nine compounds (1a-1i) with a static quenching procedure. No interaction was observed between FTO protein and compounds (1j-1 l). The thermodynamic parameters obtained from the fluorescence data showed that the hydrophobic force played a major role in stabilizing the complex. The results of synchronous and three-dimensional fluorescence spectra showed that the conformation of FTO was changed. In addition, the influence of molecular structure on the quenching effect has been investigated.

Suicide events and episodes are serious human psychiatric disorders affected by a great number of different environmental/economic factors, early trauma/abuse, human bad living habits, human genomic properties and drug intervention decisions. In order to improve antidepressant therapeutics in clinics, the relationships between efficacy and toxicities of antidepressants have to be considered fundamentally. Since the occurrences and risks of suicidal events or episodes come from interplay between insiders (chemical/genomic/bioinformatics factors) and outsiders (economic/social/ previous trauma conditions and so on), new perspectives and scientific studies must be implemented for revealing these interrelated factors step-by-step and updating therapeutics in human beings. New paradigms and clinical strategies -joint-expert groups and clinical practices (a psychiatrist with other field specialists) should be established for individual patients in future. Thus can some improvements in clinical trials be achieved in a long run?

The repair of DNA mediated by O(6)-alkylguanine-DNA alkyltransferase (AGT) provides protection against DNA damage from endogenous or exogenous alkylation of the O(6) position of guanine. However, this repair acts as a double-edged sword in cancer treatment, as it not only protects normal cells from chemotherapy-associated toxicities, but also results in cancer cell resistance to guanine O(6)-alkylating antitumour agents. Thus, AGT plays an important role in predicting the individual susceptibility to guanine O(6)-alkylating carcinogens and chemotherapies. Accordingly, it is necessary to establish a quantitative method for determining AGT activity with high accuracy, sensitivity and practicality. Here, we describe a novel nonradioactive method for measuring AGT activity using stable isotope dilution high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). This method is based on the irreversibility of the removal of the O(6)-alkyl group from guanine by AGT and on the high affinity of O(6)-benzylguanine (O(6)-BG) as an AGT substrate. HPLC-ESI-MS/MS was used to measure the AGT activities in cell protein extracts from eight tumour lines, demonstrating that AGT activity was quite variable among different cell lines, ranging from nondetectable to 1021 fmol/mg protein. The experiments performed in intact tumour cells yielded similar results but exhibited slightly higher activities than those observed in cell protein extracts. The accuracy of this method was confirmed by an examination of AGT expression levels using western blotting analysis. To our knowledge, this method is the first mass spectrometry-based AGT activity assay, and will likely provide assistance in the screening of cancer risk or the application of chemotherapies.

A series of quinazoline derivatives bearing piperazine-1-carbodithioate moiety at the C4-position were synthesized using piperidine and 1-bromo-3-chloropropane as starting materials via eight steps. Final compounds 8a–q and 9a–i were evaluated for their antiproliferative activity against human lung cancer A549, breast adenocarcinoma MCF-7, and colorectal cancer HCT-116 cell lines. The results showed that fourteen of twenty-six final compounds inhibited the proliferation of three cancer cell lines with IC50 values less than 10 μM. When treated with a representative compound 8n, HCT-116 cells were arrested at G0/G1 phase of the cell cycle. This provided a clue to further investigation of the mechanism of action.

Self-heating or even spontaneous combustion of stockpiled coal, which is likely to outbreak under favourable circumstances during its transport, process, and storage, is a long-standing thermal dynamic hazard. This hazard is harmful in diverse aspects: causing loss of coal resource and caking property, raising safety concerns upon occurrence of open fire, and giving off noxious/greenhouse effect gases. Due to the complexity of involved physical process (e.g. heat and mass transport) and chemical process (e.g. coal oxidation), formulating an analytical solution to the problem with or even without a transient approach would be a daunting task and the problem is thus more often addressed numerically. So far many numerical models to self-heating of coal have been developed and to summarise these erratic findings, this work critically reviewed theses numerical solutions since the last four decades. Mechanism of self-heating on coal mass and low temperature coal oxidation especially kinetic modelling of coal oxidation is firstly investigated to clarify the involved physical and chemical processes. On basis of the mechanistic understanding, theoretical derivations and progressive advances on governing equations like energy, mass, and momentum conservation are reviewed and compiled in details. Through parametric studies or sensitivity check these models produced fruitful but slightly inconsistent findings. Therefore to provide industry more unbiased and comprehensive guides, the present work examined the influences of various contributors including wind flow, stockpile dimensions, coal particle size, moisture content, and packing porosity on the self-heating behaviour of stockpiled coal. Last not the least, major challenges and perspectives this subject may have are briefly discussed.

AIM: To measure the transverse diameter of nasolacrimal duct in patients with nasolacrimal duct obstruction, and to analyze the difference of the transverse diameter of the upper, middle and lower nasal nasolacrimal ducts between the diseased eyes and the normal eyes, between the male and the female eyes, and of different ages and sexes and then explore the correlation between the diameter of nasolacrimal duct and nasolacrimal duct obstruction based on computed tomography(CT)dacryocystography. METHODS: From April 2014 to January 2017 in Chengdu University of Traditional Chinese Medicine Affiliated Hospital of ophthalmology in tears or pus for complaints, diagnosis of nasolacrimal duct obstruction in 152 patients(179 sick eyes, 125 normal eyes). Among them 25 cases were male(sick eyes 28 eyes, normal eye 22 eyes), 127 cases were female(sick eyes 151 eyes, normal eyes 103 eyes), age from 4 to 87 years old, mean age 53.44±16.06 years old. All patients with perfusion of 30% iohexol injection in lacrimal passages, and immediately examined with CT scan, upload CT images on PACS workstation for 3D reconstruction of nasolacrimal duct, oblique coronal of nasolacrimal duct and its adjacent structure were observed. We measured and analyzed the transverse diameters of the upper, middle and lower nasal nasolacrimal ducts between men and women, diseased eyes and non diseased eyes, and between the diseased eyes of different age groups. RESULTS: The transverse diameter of the upper, middle and lower nasal nasolacrimal duct was no significant difference between the diseased eye and the normal eye, between the male and female diseased eyes, and between the diseased eyes of different age groups(P>0.05). The transverse diameters of the upper, middle and lower nasolacrimal ducts were significantly different between the diseased eyes and the normal eyes(PCONCLUSION: Transverse diameter of bony nasolacrimal duct is not a risk factor for nasolacrimal duct obstruction.

Thermoelectric materials are of imperative need on account of the worldwide energy crisis. However, their efficiency is limited by the interplay of high electrical and lower thermal conductivities, that is, the figure of merit (ZT). Owing to their unique crystal structures, Cu–In–Te-based chalcogenides are suitable for both and thus have attracted much attention recently as potential thermoelectrics. Here we explore a newly developed Cu–In–Te derivative compound Cu3.52In4.16Te8. With a proper adjustment of Cu2Te doping, this material shows an ultralow lattice thermal conductivity (κL) (0.3 WK–1m–1) and, consequently, a figure of merit (ZT) as high as 1.65(±0.15) at 815 K: the highest value reported for p-type Cu–In–Te to date. The reduction in κL is directly related to the alteration of local symmetry around the interstitial Te, resulting in an effectively optimized phonon transport through localized “rattling” of the same. Although the Hall carrier concentration reduces upon Cu2Te addition due to the unpinning of the Fermi level (EFermi) toward the conduction band minimum, the power factor remains stable. The knowledge depicted here not only demonstrates the potential of Cu3.52In4.16Te8-based alloys as a promising TE, but also provides guidelines for developing further high-performance thermoelectric materials by enhancing the electronic conductivity.

Climate change is anticipated to raise overall temperatures in the twenty-first century and is likely to intensify population exposure to heat during the warm season and, as a result, increase the risk of heat-related illnesses and deaths. While earlier studies of heat exposure and related health impacts generally focused on the acute effects of short-term exposure indicated by high daily temperature or several days of very hot weather, recent research has suggested that small changes in seasonal average temperature over a long period of time is likely to pose significant health risk as well. Using downscaled climate projections under three Representative Concentration Pathways emission scenarios, high-spatial-resolution population data, and the latest population projections by the United Nations, we aim at projecting future changes in long-term population exposure to summer heat across China in the mid- and late-twenty-first century resulting from global climate change. As the impacts of population growth are often overlooked in projecting future changes in heat exposure, we estimated changes in population-weighted average temperature in the warmest quarter over two future 20-year time periods and compared them with changes in temperature only. Our analysis shows that, nationally, population-weighted average temperature in the warmest quarter is projected to increase by 2.2 °C relative to the current situation in the 2050s and by 2.5 °C in the 2070s, as the result of climate change and population growth. Despite the foreseeable population stabilization in China, changes in population-weighted temperature are projected to be higher than changes in temperature itself for the majority of the 33 provinces (ranging from 0.02 °C to 1.27 °C, or 1% to 126% higher in the 2050s and from 0.02 °C to 1.16 °C, or 1% to 73% higher in the 2070s), with the largest differences mainly occurring in Western China. The impact of urbanization is projected to be relatively insignificant. Our findings provide evidence of possible underestimation of future changes in long-term exposure to summer heat if the effect of population growth is not factored in.

With the rapid growth of big data and network information, it is particularly important to perform information query and intelligent analysis on unstructured massive data in large-scale complex systems. The existing methods of directly collating, sorting, summarizing, and storing retrieval of documents cannot meet the needs of information management and rapid retrieval of massive data. This paper takes the standardized storage, effective extraction and standardized database construction of massive resume information in social large-scale complex systems as an example, and proposes a massive information query and intelligent analysis method. The method utilizes the semi-structured features of the resume document, constructs the extraction rule model of various resume data to extract the massive resume information. On the basis of HBase distributed storage, with the help of parallel computing technology to optimize the storage and query efficiency, which ensures the intelligent analysis and retrieval of massive resume information. The experimental results show that this method not only greatly improves the extraction accuracy and recall rate of resume information data, but also compared with the traditional methods, there are obvious improvements in the three aspects of massive information retrieval methods, query usage efficiency, and the intelligent analysis of complex systems.

Dust particles floating inside roadways are characterized by various sizes. However, it is difficult to replicate the dust environment with such factors taken into consideration in laboratory experiments. Fortunately, computational technology provides an alternative way for that. In this study, in order to investigate the movement mechanism of dust with different diameters from heading face in the underground roadway, a three-dimensional CFD-DEM coupling numerical model is presented using the Eulerian-Lagrangian method. A numerical roadway model based on a practical engineering case has been established for the purpose of studying the dust diffusion under single-forced ventilation condition in roadway underground. The study suggests that particle size has a significant effect on dust dispersion. The results demonstrate that CFD-DEM coupling computational simulation can be an effective approach for the investigation of dust issues in underground engineering.

Generalized anxiety disorder (GAD) is a significant and common mental illness with a lifetime prevalence of 3.7%. Regardless of the complexity of treatment decisions for GAD, few studies have conducted systematic comparisons of the efficacies of varying interventions. Thus, this study performed a valid network meta-analysis (NMA) of randomized controlled trials (RCTs) to synthesize direct and indirect evidence for alternative interventions for GAD. We searched four major bibliographic databases, the Cochrane Central Register of Controlled Trials, Embase, PsycINFO, and PubMed, for published RCTs of adult patients with a diagnosis of GAD and allowed for all comorbidities. A total of 91 articles (14,812 participants) were identified in the final NMA. The results showed that all pharmacological treatments except for serotonin modulators and second-generation antipsychotics had greater effects than placebo: norepinephrine-dopamine reuptake inhibitors (standardized mean difference (SMD) -1.84, 95% credible interval -3.05 to -0.62), noradrenergic and specific serotonergic antidepressants (-0.91, -1.62 to -0.20), melatonergic receptor agonists (-0.68, -1.15 to -0.21), selective serotonin reuptake inhibitors (SSRIs; -0.67, -0.90 to -0.43), azapirones (-0.58, -1.00 to -0.17), anticonvulsants (-0.56, -0.85 to -0.28), serotonin-norepinephrine reuptake inhibitors (SNRIs; -0.54, -0.79 to -0.30), and benzodiazepines (BZDs; -0.40, -0.65 to -0.15). Most psychological and self-help interventions exerted greater effects than the waitlist group. However, no psychological interventions had greater effects compared with the psychological placebo. Overall, most pharmacological interventions had larger effect sizes than psychological interventions, and most psychological interventions showed larger effect sizes than self-help interventions.

Gas pressure changes during the process of coal mine gas drainage and CBM recovery. It is of great importance to understand the influence of sorption pressure on gas diffusion, however, the topic remains controversial in past studies. In this study, four samples with different coal ranks were collected and diffusion experiments were conducted under different pressures through the adsorption and desorption processes. Three widely used models, i.e., the unipore diffusion (UD) model, the bidisperse diffusion (BD) model and the dispersive diffusion (DD) model, were adopted to compare the applicability and to calculate the diffusion coefficients. Results show that for all coal ranks, the BD model and DD model can match the experimental results better than the UD model. Concerning the fast diffusion coefficient Dae of the BD model, three samples display a decreasing trend with increasing gas pressure while the other sample shows a V-type trend. The slow diffusion coefficient Die of BD model increases with gas pressure for all samples, while the ratio &beta, is an intrinsic character of coal and remains constant. For the DD model, the characteristic rate parameter k&Phi, does not change sharply and the stretching parameter &alpha, increases with gas pressure. Both Dae and Die are in proportion to k&Phi, which reflect the diffusion rate of gas in the coal. The impacts of pore characteristic on gas diffusion were also analyzed. Although pore size distributions and specific surface areas are different in the four coal samples, correlations are not apparent between pore characteristic and diffusion coefficients.

Precise prediction of coal thickness is of the utmost importance in realizing intelligent and unmanned mining. As the channel wave is characterized by an easily recognizable waveform, a long propagation distance, and strong energy, it is widely used for coal thickness inversion. However, most traditional inversion methods are local in nature, and the inversion result is probably not optimal in the global scope. This paper introduces the GA-SIRT hybrid approach, which combines Genetic Algorithms (GA) and Simultaneous Iterative Reconstructive Techniques (SIRT) in order to deal with the above problem and to improve the accuracy of coal thickness inversion. The proposed model takes full advantage of the strong global search capability of GA and of the fast local convergence rate of the SIRT. Moreover, it inhibits the poor local search ability and the local optimal value effect of the GA and the SIRT respectively. The application of the GA-SIRT in the Guoerzhuang coal mine has significantly enhanced its accuracy, stability, and overall computational efficiency. Hence, the introduced novel hybrid model can precisely resolve and identify the coal thickness according to the channel wave. It can also be extended to other geophysical tomographic inversion problems towards the reduction of potential local optimal solutions.

Considered as a key component of human capital, mental health has drawn substantial scholarly attention for its effect on people's health status and economic outcome. When facing the challenge of stress, people's heterogeneity in cognitive ability and non-cognitive ability causes difference in patterns of coping, resulting in different manifestations in mental health. Previous researches have shown that cognitive and non-cognitive abilities have positively direct or indirect effects on mental health, but few studies research their role of coping with air pollution. We used the China Family Panel Survey (CFPS) and matched individual data with county or district level PM2.5 information from NASA. The study found that air pollution has negative effect on mental health with every increase of 1μg/m3 in PM2.5 deteriorating mental health by 0.038 standard deviation, which is the total effect of air pollution. However, the direct effect of air pollution on mental health will decrease to 0.028 in absolute value when considering mediating effects. By employing different approaches, we found positive mediating effects via cognitive ability and non-cognitive ability. Individuals with high cognitive and non-cognitive abilities are able to accurately diagnose problems and select the optimal coping strategies, thus restoring positive mental health.

The analysis of the relationship between personality and depression can facilitate the development of subclinical preventive measures and clinical treatment schemes. Moreover, the personality is associated with a variety of mental diseases, and there is substantial comorbidity between depression and some other mental diseases. So, to reveal pathological relationships between personality and depression is helpful to understand the etiology of the comorbidity between depression and multiple mental disorders. In this review, we first summarize the empirical researches on the relationship between personality and depression from the aspects of behavior and neural mechanisms, and then discuss the hypothetical model to explain the relationship between personality and depression. In a word, high neuroticism, low extroversion and conscientiousness, and other related traits (rumination, self-criticism, dependency, etc.) have a moderate to strong correlation with depression. Among them, neuroticism is the most concerned. To a certain extent, it can predict the onset of depression and affect the duration and treatment outcome of depression. Other traits, such as positive emotionality/ extroversion and effortful control/responsibility, can moderate the relationship between negative emotionality/neuroticism and depression. And after the onset of depression, the neuroticism may change, but the extroversion does not seem to change.

A series of catalysts with p-LaFeO

This paper presents the results of an evaluation study of gas drainability in the Bulli seam in the Southern Coalfield of the Sydney Basin, NSW, Australia, where the coal seam gas (CSG) contains a high proportion of carbon dioxide (CO2). Historically the gas drainability in some particular areas of this coal seam was found to be particularly poor, which posed a significant challenge to gas predrainage. As a result, a large volume of greenhouse gases were released to the atmosphere during mining of the coal seam. Furthermore, the high gas content associated with the CO2-rich composition also increased the risks of coal and gas outburst incidents, affecting the safety of mining. After systematic literature review of evaluation factors affecting gas drainability, this evaluation study comprehensively analyzed the main critical factors, including the geology of the area, the coal cleat system, coal microstructure, coal permeability, coal sorption capacity, gas content, and gas composition. Field geology analysis showed geological variations that affected the variations of the coal cleat system and CO2 content in the coal seam. Scanning Electron Microscope (SEM) tests showed the tight and less-porous features in hard-to-drain coal samples. The colliery gas database analysis was carried out to assess the impact of gas content and gas composition on the drainability of the coal seam. Laboratory tests showed that the coal seam had a permeability of less than 1 mD and also showed that the coal seam was highly undersaturated, especially with high CO2 content.

Neuroleptic malignant syndrome (NMS) is rare but one of the most serious adverse effects of antipsychotics. Here, we report a case of risperidone-associated NMS in which a successful rechallenge of risperidone was observed with a positive follow-up. A 47-year-old female with schizophrenia was treated with risperidone 4 mg/d for 8 months in 2009 and was admitted to our hospital in 2015 owing to violent behavior under persecutory delusions. Risperidone 2 mg/d was initiated and increased to 4 mg/d 54 days later. Further, long-acting injectable (LAI) risperidone 25 mg per two weeks was added on hospital day 15. On hospital day 116, NMS occurred and thus we discontinued all antipsychotics including LAI risperidone, then NMS improved. We resumed LAI risperidone 25 mg per two weeks on hospital day 148, thus we waited for 22 days before re-starting the drug treatment. She was discharged on hospital day 371, then switched to LAI paliperidone 150 mg per four weeks 2 months later. At the time of a follow-up 3 years later, NMS had not reoccurred. This case reports on an unusual presentation of NMS in which no hyperthermia was observed. Furthermore, this case indicated that NMS may occur in a dose-dependent manner. In conclusion, this case reported important information for clinicians with regard to antipsychotic drug rechallenges and proper dosing of APs to avoid or reverse NMS.

Background Cardiovascular complications, especially myocardial infarctions (MIs), are the leading mortality cause in diabetic patients. The transplantation of stem cells into damaged hearts has had considerable success as a treatment for MI, although whether antidiabetic drugs affect the therapeutic efficacy of stem cell transplantation is still unknown. This study aims to understand whether and how metformin, one of the first-line drugs used to treat type 2 diabetes mellitus (T2DM), induces mesenchymal stromal cell (MSC) apoptosis and dampens their cardioprotective effect after transplantation into infarcted hearts. Methods A mouse MI model was generated via permanent ligation of the left anterior descending (LAD) coronary artery. MSCs with or without metformin treatment were transplanted after MI in diabetic mice. Echocardiography was used to assess cardiac function and determine cardiac remodeling, and TTC staining was performed to evaluate infarction size. A mouse gavage model was performed to evaluate bone marrow MSCs for flow cytometry assay. Results Metformin dampened MSC therapeutic efficacy, which increased infarct size and restricted functional cardiac recovery. Specifically, metformin induced the activation of AMP-activated protein kinase (AMPK)-mediated apoptosis through the inhibition of S6K1-Bad-Bcl-xL cell survival signaling, resulting in the upregulated expression of apoptosis-associated proteins and increased MSC apoptosis. Accordingly, counteracting AMPK attenuated metformin-induced apoptosis in MSCs and partially restored their cardioprotective effects in diabetic mice with MI. Furthermore, a decrease in peripheral blood MSCs was found in patients with T2DM who had a metformin medication history. Conclusions Our results highlight an unexpected adverse effect of metformin-induced MSC apoptosis through AMPK-mediated mTOR suppression, which is attenuated by an AMPK inhibitor. Moreover, AMPK inhibition may be a novel strategy for enhancing the effectiveness of stem cell therapy after MI in diabetes. Electronic supplementary material The online version of this article (10.1186/s13287-018-1057-0) contains supplementary material, which is available to authorized users.

Eight half-sandwich iridiumIII (IrIII) complexes of the general formula [(η5-Cpxbiph)Ir(O^N)Cl] (Cpxbiph is tetramethyl(biphenyl)cyclopentadienyl, and the O^N is α-picolinic acid chelating ligand and its derivatives) were synthesized and characterized. Compared with cis-platin widely used in clinic, target IrIII complexes showed at most five times more potent antitumor activity against A549 cells by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. IrIII complexes could be transported by serum albumin, bind with DNA, catalyze the oxidation of nicotinamide-adenine dinucleotid (NADH) and induce the production of reactive oxygen species, which confirmed the antitumor mechanism of oxidation. IrIII complexes could enter A549 cells followed by an energy-dependent cellular uptake mechanism, meanwhile, target the mitochondria and lysosomes with the Pearson's colocalization coefficient of 0.33 and 0.74, respectively, lead to the lysosomal destruction and the change of mitochondrial membrane potential (ΔΨm), and eventually induce apoptosis.

Coal mine dust continues to be a health and safety issue in underground coal mines. Coal seam water infusion was developed and widely applied in European coal mines for dust control, and was also a common practice in most Chinese coal mines. This method typically involves the infusion of water into the coal seam to increase its moisture content, and therefore reduce dust generation during mining operations. With the availability of other dust control methods such as water spraying systems, the water infusion method has not been considered as a viable means for dust mitigation in modern mines. However, the increase in production output and the deployment of more powerful equipment for coal cutting and transport and intensive gas drainage practices mean that workers could be exposed to more dust contaminations. Whilst the mine operators are committed to suppress and dilute airborne dust particles using these passive measures, there is a need to critically examine and subsequently develop this proactive dust control technology for practical applications in Chinese coal mines. The paper provides a critical review of the water infusion technologies in view of its technological advances and practical application limitations. The methods of water infusion, mechanism of water flow in coal, the role of surfactants and the key parameters influencing the effect of water infusion on dust control are identified and discussed. Existing problems and prospects for water infusion are analysed.

In order to overcome the low accuracy of the traditional method, a fast identification method based on the improved K-mean algorithm is proposed. Spatial grid block model is constructed to extract the fingerprint texture features and then the fingerprint profile features are detected using the edge outline extraction method. The Kalman fusion method is used to reconstruct fingerprint information. Using the neighbourhood distributed retrieval method, fingerprint image feature fusion is realised and the texture feature extraction model for forged fingerprints is established. The K-means clustering method is used for fingerprint feature clustering to realise fast identification of forged fingerprints. Experimental results show that the identification accuracy of this method is higher than 0.85, and the identification stability is good. The signal-to-noise ratio of fingerprint images is always between 25.3 dB and 82.3 dB, and the imaging quality is high, indicating that this method can realise fast and accurate identification of forged fingerprints.

This paper introduces a novel standing support incorporating fibre-reinforced polymer (FRP), termed FRP tubular standing support (FTSS). The exterior container of FTSS is the small rupture strain (SRS) GFRP tube wrapped with ultra-high molecular weight polyethylene (UHMWPE) FRP jacket with large rupture strain (LRS), while the infill is the coal rejects based backfill material (CBM). The CBM is made of industrial by-product (i.e. coal rejects) and high flowable cementitious grout material, leading to some environmental and economic benefits when it is used in underground mines. Test variables included the type of coal rejects (i.e. screened and unscreened), the thickness of SRS FRP tube (i.e. 1.5 mm and 3.0 mm) as well as the thickness of LRS FRP jacket (i.e. 2-ply, 3-ply and 4-ply). Test results showed that both the load carrying capacity and deformation ability of CBM in FTSS have been significantly enhanced attributed to the confinement provided by exterior FRP container. Existing stress–strain model for FRP-confined normal concrete can be used to reasonably predict the compressive behaviour of confined CBM in FTSS with large deformation ability. The ductile FTSS is suitable for underground spaces and infrastructures where the integrity of structure is the main concern.

Many researchers have concluded that the permeability should be measured after the adsorption equilibrium state is reached and in many permeability models, it is normally assumed that pm (pressure in the coal matrix) is equalized with pf (pressure in the fractures). However, when the dynamic balance between pm and pf is broken which exists in most coalbed methane engineering, the differences between the two pressures induced by gas diffusion and matrix shape factor will generate nonuniform matrix swelling which have not been well learned to date, thus influence the permeability evolution. It is of great importance to investigate this issue on account of it will play a more important role in CO2-enhanced coalbed methane and CO2 sequestration engineering as the coal adsorption capacity for CO2 is considerably higher than that for CH4. To achieve this target, a series of novel coal permeability tests and simultaneous strain measurements were conducted using both natural coal and reconstituted coal. In these experiments, the radial strain evolution characteristics and the permeability evolution characteristics as a function of the adsorption equilibrium time and confining pressure were obtained. Based on the experimental results, the effects of the differences between pm and pf on radial strain evolution and coal permeability evolution were discussed, and a new matrix swelling area propagation theory was achieved. In addition, the differences between natural coal and reconstituted coal in terms of their matrix swelling and stress sensitivity properties were obtained.

Spontaneous heating of coal stockpile has long been a thermal dynamic hazard during coal storage, processing, and transport. A transient non-equilibrium thermal CFD model has been developed to study the low-temperature self-heating behaviour of coal in multiple stockpiles under different prevailing wind conditions. Modelling results from the initial steady wind flow simulation indicate that a wake region can be induced on the leeward side of each coal stockpile. Pressure coefficient drops when the wind stream encounters or leaves a stockpile and the pressure coefficient profiles of multiple stockpiles tend to have more resemblance with a wider spacing. The first stockpile acts like a wind barrier to the adjacent stockpiles and the maximum temperature of it tends to be the first approaching the critical temperature. A ‘hot spot’ will develop and then migrate towards deep regions in each of these stockpiles that are loosely compacted under higher wind velocity conditions. Wind velocity and porosity of stockpile have significant influences on self-heating behaviour of the stockpiles and transport pattern of gaseous products liberated by coal oxidation. Compacting stockpiles from loosely packed scenario to slightly packed scenario might not be able to slow down the temperature rising rate at low-temperature range but could considerably minimize the volume of deteriorated coal. The highest temperature rising profiles of the stockpiles located in downwind side can approach to that of the first stockpile, particularly when they are more widely stacked. Stacking coal stockpiles as close as practically possible is recommended to maximise the “protection” of adjacent stockpiles but would cause undesirable accumulation of carbonic gases. Stockpiles in low height and gentle slope will have a prolonged safe storage period, especially for the first stockpile directly facing the wind direction. However, it may not slow down the self-oxidation process of the adjacent stockpile at very initial stage due to “weakened protection” of the first stockpile. This study has practical reference to coal industry especially where multiple coal stockpiles require to be constructed.

As one of the most important parts of the solar power tower plant, the receiver plays an important role in the high-efficiency operation of the solar power tower system. Obtaining the maximum available energy in the receiver is highly desired in real-world operations. In this paper heat transfer and exergy transfer methods are used to model the energy transfer process in a collector tube. Different from common analysis methods, in order to ensure the molten salt to obtain the maximum available energy, an objective function is proposed to convert the task into a constrained optimization problem. The gravitational search (GS) algorithm is employed to search for the optimal solution of the proposed objective function. Numerical results indicate that the proposed optimization method can find the optimal operation parameters under different conditions. The heat transfer and exergy transfer characteristics along the collector tube under the optimal working condition are revealed, which quantifies the available energy along the collector tube, as well as reveals the location of energy degradation in the tube. The research findings will provide a beneficial reference for the effective use of the solar energy.

Coal seams that are prone to strong outbursts have low strength and cause heavy structural damage to the seam. Their outburst risk is highly related to the release of the adsorbed coalbed gas, which is controlled by the gas desorption and diffusion characteristics of coal. In the Haizi Coal Mine, China, an extremely high gas outburst risk was detected, and the coals from this area were found to have an unprecedented high degree of fragmentation and were present in the pulverized state. To explain the pulverization characteristics of the pulverized coal, the related physical parameters were investigated; the gas desorption and diffusion properties of the pulverized coal were analyzed and compared with those of the unpulverized coal. The results indicated that the pulverized coal could easily reach the required degree of fragmentation for a coal and gas outburst to occur. Furthermore, the pore volume and specific surface area of the pulverized coal differed according to the coal particle size. Compared with the unpulverized coal, the gas desorption and diffusion properties of the pulverized coal were largely varied, and the pore structure of the pulverized coal was much simpler. The formation of pulverized coal is believed to be closely related to complex geological conditions.

Kaiping coalfield is located in Tangshan, northern China, and the area has been mined for 130 years. The main structure is the Kaiping syncline with an axis that generally strikes north–east to east–west. Since 1998, we have measured the in situ stress using overcoring and obtained 30 sets of data in eight coal mines with depths from −260 to −1238 m. Based on the measured data, we established the trends in maximum horizontal stress, vertical stress, minimum horizontal stress, and their ratios, and the ratio of mean horizontal stress to vertical stress and depth. The relationship between magnitude and orientation of maximum horizontal stress and their relationships to the Kaiping syncline are discussed. The results show that (1) the stress field of the Kaiping coalfield is complex and non-uniform. The orientation and magnitude of principal stress from stress measurement diverge widely from the regional stress field and the stress regime, with 77 % strike-slip faulting and the remainder thrust faulting. (2) Both maximum (σ H) and minimum (σ h) horizontal stresses have significant differences at a similar depth; however, vertical stress σ v increases linearly with depth with a gradient of 0.025 MPa/m. The ratio (k) of the mean horizontal stress to vertical stress is 160/h + 1.04

In this work, we have synthesized five pyrazole derivatives (1a–1e). The interactions between fat mass and obesity-associated (FTO) protein and pyrazole derivatives have been investigated by fluorescence, synchronous fluorescence spectroscopy and UV–vis absorption. Results indicate that the intrinsic fluorescence of FTO can be quenched by the derivatives through a static quenching procedure. The binding constants and thermodynamic parameters at different temperatures were obtained. Thermodynamic results indicate that hydrophobic interaction forces play major role in the binding between 1a–1d and FTO. Pyrazole derivative 1e binds to FTO through van der Waals forces and hydrogen bonds. Results also show that 1e has the strongest quenching and binding ability among five pyrazole derivatives.

After long defeats-almost no marked breakthrough in HIV vaccination campaign has been observed during the past two decades, and we still have not lost our faiths for the development of highly effective and low risk HIV vaccines. Many effective vaccines have been discovered and will certainly enter into the markets within the next 5 to 10 years. In order to promote HIV vaccine developments and clinical HIV therapeutic improvements, this perspective addresses the good and bad sides of currently available HIV vaccines, discusses many subjects of medical significance and finally provides up-to-date information in the field of HIV studies, in particular regarding vaccine developments and HIV pathogenesis.

A transversely isotropic continuum elasto-viscoplasticity model, which was developed from Chaboche’s unified constitutive model, was formulated to capture the thermal mechanical creep fatigue deformation behavior of a directionally solidified nickel-based superalloy. A fourth-order tensor was introduced to model material anisotropy. In order to model the tertiary creep behavior, the Kachanov damage evolution equation was coupled into the stress tensor. Based on the test results of uniaxial tensile, fatigue, and creep loadings at isothermal temperature conditions, the material parameters are obtained. Thermal mechanical fatigue (TMF) and creep–fatigue interaction test results were used to verify the robustness of the model. Additionally, strain–temperature-dependent stress–strain responses under TMF loadings were analyzed using the present model. Under strain-controlled conditions, both of the stress ranges and mean stresses are strongly influenced by the strain–temperature phases, a key parameter for TMF tests.

Two main theories have been used to explain the arithmetic split effect: decision-making process theory and strategy choice theory. Using the inequality paradigm, previous studies have confirmed that individuals tend to adopt a plausibility-checking strategy and a whole-calculation strategy to solve large and small split problems in complex addition arithmetic, respectively. This supports strategy choice theory, but it is unknown whether this theory also explains performance in solving different split problems in complex subtraction arithmetic. This study used small, intermediate and large split sizes, with each split condition being further divided into problems requiring and not requiring borrowing. The reaction times (RTs) for large and intermediate splits were significantly shorter than those for small splits, while accuracy was significantly higher for large and middle splits than for small splits, reflecting no speed-accuracy trade-off. Further, RTs and accuracy differed significantly between the borrow and no-borrow conditions only for small splits. This study indicates that strategy choice theory is suitable to explain the split effect in complex subtraction arithmetic. That is, individuals tend to choose the plausibility-checking strategy or the whole-calculation strategy according to the split size.

The interactions between human serum albumin (HSA) and 5-epi-taiwaniaquinone G (G2) or its isomeride (G1) was investigated by fluorescence, UV–visible absorption, resonance light scattering, synchronous fluorescence spectroscopy and 3D spectroscopy under mimic physiological conditions in combination with molecular modeling. The results revealed that G1 and G2 caused the fluorescence quenching of HSA by the formation of G1-HSA and G2-HSA complex, respectively. The binding constants and thermodynamic parameters at three different temperatures were obtained. Hydrophobic and electrostatic interactions played a role in the binding process of HSA and G1. Van der Waals force and hydrogen bond interaction played a role in the binding process of HSA and G2. Results showed that G2 was the stronger quencher and the position of methyl influenced the binding process between HSA and G1 (G2).

Mine dust is one of the main hazards in underground longwall mines worldwide. In order to solve the mine dust problem, a significant number of studies have been carried out regarding longwall mine dust control, both in China and Australia. This paper presents a comparative study of dust control practices in Chinese and Australian longwall mines, with particular references to statutory limits, dust monitoring methods and dust management practices, followed by a brief discussion on the research status of longwall mine dust control in both countries. The study shows that water infusion, face ventilation controls, water sprays, and deep and wet cutting in longwall shearer operations are commonly practiced in almost all underground longwall mines and that both Chinese and Australian longwall mine dust control practices have their own advantages and disadvantages. It is concluded that there is a need for further development and innovative design of more effective dust mitigation products or systems despite the development of various dust control technologies. Based on the examinations and discussions, the authors have made some recommendations for further research and development in dust control in longwall mines. It is hoped that this comparative study will provide beneficial guidance for scholars and engineers who are engaging in longwall mine dust control research and practice. Keywords: Dust control, Longwall coal mine, Dust monitoring, Ventilation, Water spray, Foam technology for dust control (FTDC)

The collector tubes in a receiver play a vital role in the solar power tower system, and directly influence the cost of the power generation. Fast forecast of the temperatures of the collector tubes from the limited number of the temperature measurement data is important. Different from the common computational fluid dynamics prediction method, in this study a back-propagation neural network method is developed to fast acquire the temperature of the receiver, such as the peak temperatures of the inner and outer surfaces, and the outlet mean temperature and the outlet highest temperature of the molten salt. The numerical simulations are implemented to validate the feasibility and effectiveness of the proposed method. Moreover, in the proposed method the temperatures of the tube wall and the molten salt can be fast forecasted without the thermal physical parameters of materials, the boundary conditions or the initial conditions, and the solution of the complicated governing equations.

To understand the phyletic evolution of geese, the complete mitogenome of the Zhedong goose was sequenced for the first time. It is composed of 37 genes and 1 control region, and the structure and arrangement of all genes sequenced are identical to those of other goose breeds. We confirmed the accuracy of the mitogenome sequence through RT-PCR and found numts from amplification in genomic DNA. Comparisons of the phylogenetic trees and sequences of geese that were suggested a clade of Chinese geese, except the Yili goose, were classified in the Euro clade. Several breed-specific mutations and Chinese breed-specific mutations were found. Our results suggest that Chinese geese evolved from the swan goose, splitting from their common ancestors at different times, which was consistent with studies before. Furthermore, numts in most genes of Zhedong goose clustered with European geese in the phylogenetic tree, suggesting that the haplotypes in the Euro clade might be more ancient. However, the mitogenome of the swan goose shows distinctive evolutionary positions in some genes, which suggest its unclear relationship with Chinese geese and European geese. The current study added to the understanding of the evolution of geese and provided evidence that the typing of numts is an encouraging way for the evolutionary study of geese and the mitochondrial genomes of geese deserve further investigation.

The contents of lead, cadmium, chromium, copper, and nickel were determined in 25 tea samples from China, including green, yellow, white, oolong, black, Pu'er, and jasmine tea products, using high-resolution continuum source graphite furnace atomic absorption spectrometry. The methods used for sample preparation, digestion, and quantificational analysis were established, generating satisfactory analytical precisions (represented by relative standard deviations ranging from 0.6% to 2.5%) and recoveries (98.91–101.32%). The lead contents in tea leaves were 0.48–10.57 mg/kg, and 80% of these values were below the maximum values stated by the guidelines in China. The contents of cadmium and chromium ranged from 0.01 mg/kg to 0.39 mg/kg and from 0.27 mg/kg to 2.45 mg/kg, respectively, remaining in compliance with the limits stipulated by China's Ministry of Agriculture. The copper contents were 7.73–63.71 mg/kg; only 64% of these values complied with the standards stipulated by the Ministry of Agriculture. The nickel contents ranged from 2.70 mg/kg to 13.41 mg/kg. Consequently, more attention must be paid to the risks of heavy metal contamination in tea. The quantitative method established in this work lays a foundation for preventing heavy metal toxicity in human from drinking tea and will help establish regulations to control the contents of heavy metals in tea.

Several mines operating in the Bulli seam of the Sydney Basin in NSW, Australia are experiencing difficulties in reducing gas content within the available drainage lead time in various sections of the coal deposit. Increased density of drainage boreholes has proven to be ineffective, particularly in sections of the coal seam rich in CO2. Plus with the increasing worldwide concern on green house gas reduction and clean energy utilisation, significant attention is paid to develop a more practical and economical method of enhancing the gas recovery from coal seams. A technology based on N2 injection was proposed to flush the Coal Seam Gas (CSG) out of coal and enhance the gas drainage process. In this study, laboratory tests on CO2 and CH4 gas recovery from coal by N2 injection are described and results show that N2 flushing has a significant impact on the CO2 and CH4 desorption and removal from coal. During the flushing stage, it was found that N2 flushing plays a more effective role in reducing adsorbed CH4 than CO2. Comparatively, during the desorption stage, the study shows gas desorption after N2 flushing plays a more effective role in reducing adsorbed CO2 than CH4.

In this study, P- and S-wave velocity models were built based on two pre-stack depth migration (PSDM) profiles of long-offset reflection data and 25 four-component ocean-bottom seismometers (OBS) data at Jiulong Methane Reef off SW Taiwan in the passive margin of the northern South China Sea (SCS). According to the velocity models, the average P-wave velocity and Vp/Vs ratio of the free gas beneath the bottom-simulating reflector (BSR) are 1.52–1.58 km/s and 4.5–5.10, respectively. The depth of the BSR is found at 80–300 m below the sea floor and the sedimentary thickness of the hydrate and the free gas are about 50–100 m and 70–100 m, respectively. P-wave velocity of about 1.75 km/s in the hydrate-bearing sediment is southeastward increased to about 1.85 km/s above the BSR. Similarly, Vp/Vs ratio of about 3.06 in the hydrate-bearing sediment is increased southeastward to about 3.48 above the BSR. Based on the pseudo-3D map of gas-hydrate saturation estimated from the PSDM and OBS models, the average saturations of hydrate and free gas at Jiulong Methane Reef are about 7% and 0.9–2.4%, respectively. The highest hydrate saturation (11%) is located at 5–20 m above the BSR in the SE portion of the Jiulong Methane Reef. On the other hand, the highest gas saturation of about 2% is observed at 10–70 m below the BSR in the NW portion of the Jiulong Methane Reef. We suggested that several normal faults dipping southeastward beneath the continental slope provided conduits for gas migrating northwestward at Jiulong Methane Reef. Therefore, the highest gas saturation is observed below the anticline in the NW portion of the Jiulong Methane Reef and the highest hydrate saturation (high P-wave velocity and high Vp/Vs ratio) is identified above the BSR in the SE portion of the Jiulong Methane Reef.

The binding interaction of neutral red (NR) with bovine hemoglobin (BHb) was studied by fluorescence spectroscopy in combination with molecular modeling. NR quenched the intrinsic fluorescence of BHb via a static mechanism. According to relevant data, the binding constants were calculated at two different temperatures. The thermodynamic parameters obtained from the fluorescence data showed that the hydrophobic and electrostatic interactions played a major role in stabilizing the complex. Synchronous and three-dimensional fluorescence spectra of BHb were investigated in the presence of NR. The results showed that the environment of tryptophan and tyrosine residues was altered by the dye. The fluorescence experimental results were in agreement with the results obtained by molecular modeling study.

Ischemia/reperfusion injury (IRI) has lzong been an area of concern and focus of investigations. Erythropoietin (EPO) exhibits multiple protective effects, and selenium is an antioxidant trace element in the body, however, there have been no reports concerning the effects of EPO combined with sodium selenite on IRI. In the present study, a mouse model of renal IRI (RIRI) was pre‑treated with EPO and sodium selenite to determine the most appropriate combination ratio of the two for further investigation. The results revealed that EPO and sodium selenite had synergistic protective effects in RIRI. EPO was identified as the predominant treatment component, with sodium selenite serving as an adjuvant, and combination treatment was markedly more effective, compared with treatment with either drug alone. The optimal ratio of treatment was 10:1 (10 IU EPO: 1 µg sodium selenite). The results indicated that RIRI markedly induced renal injury, as evidenced by elevated levels of blood urea nitrogen (BUN), as well as higher pathological scores, based on hematoxylin and eosin staining. Pre‑treatment with EPO and sodium selenite significantly decreased serum expression levels of BUN and malonaldehyde, and increased the expression levels of superoxide dismutase, glutathione peroxidase and nitric oxide (NO), compared with the model group. Furthermore, co‑treatment with EPO and sodium selenite upregulated the protein expression levels of phosphatidylinositol‑3 kinase (PI3K) in renal tissue samples. Together, the results suggested that co‑administration of EPO and sodium selenite effectively ameliorates IRI‑induced renal injury by reducing oxidative stress and activating the PI3K/NO signaling pathway.

In a transitional economy such as China's, when resources are unevenly distributed across different sectors, the disadvantaged sector may seek a growth path that bypasses resource constraints. We investigated this phenomenon in the context of the Chinese real estate industry. By comparing the post–merger and acquisition (M&A) performance of acquiring firms between state-owned enterprises (SOEs) and privately-owned enterprises (POEs), we attempted to show that POEs are better performers in the market should they be granted equitable resources, and the superior performance is strengthened by market-oriented institutional environment. We used M&A events data of publicly listed real estate firms in China from 2004 to 2012, in conjunction with firm characteristics and province-level market environment data. We found the results to be consistent with our hypotheses. In particular, compared to SOEs, privately-owned acquiring firms tend to have better post-M&A performance when both the regions of the acquirer and the target have high level of marketization. The results suggest that the private sector in China's transitional economy is potentially more efficient than the state-owned sector, as long as the market environment is favorable.

Pedicularis cheilanthifolia is an ecologically important species in alpine meadows of central and western China. In this study, the complete chloroplast genome (cpDNA) sequence of P. cheilanthifolia was characterized using Illumina pair-end sequencing. The cpDNA is 155,159 bp in length, and contains a pair of 25,966 bp inverted repeats (IR), one large single copy (LSC) region of 85,256 bp, and one small single copy (SSC) region of 17,971 bp. It contains 133 genes including 87 protein-coding genes (79 PCG species), 8 ribosomal RNA genes (4 RNA species), 37 transfer RNA genes (30 tRNA species) and 1 pseudogene (ndhF). The overall AT content of the whole genome is 62.3%, and the corresponding values of the LSC, SSC and IR regions are 64.3, 68.4 and 57.0%, respectively. Phylogenetic analysis based on ten chloroplast genomes indicates that P. cheilanthifolia is closely related to Castilleja paramensis.

The complete chloroplast genome sequence of Cortusa matthioli subsp. pekinensis has been characterized using Illumina pair-end sequencing. The circular genome is 152,239 bp in length, containing a pair of inverted repeats (IRs) of 25,677 bp, separated by a large single copy (LSC) and a small single copy (SSC) region of 83,026 and 17,859 bp, respectively. It contains 131 genes, including 85 protein-coding genes (78 PCG species), 37 transfer RNA genes (28 tRNA species) and eight ribosomal RNA genes (four rRNA species). The most of gene species occur as a single copy, while 18 genes are duplicated. The nucleotide composition is asymmetric (31.1% A, 19.0% C, 18.2% G and 31.7% T) with an overall AT content of 62.8%. The corresponding values for the LSC, SSC and IR regions are 64.7, 69.8 and 57.2%, respectively. Phylogenetic analysis suggested that C. matthioli subsp. pekinensis is closely related to Primula species.