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In this study, the support effects on the Pd-catalyzed semi-hydrogenation of acetylene have been investigated from the structural and kinetic perspectives. According to the results of kinetic analysis and X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction, temperature-programmed hydride decomposition, and in situ X-ray diffraction measurements, using carbon nanotubes as support for Pd nanocatalysts with various sizes instead of α-Al2O3 decreases the Pd0 3d binding energy and suppresses the formation of undesirable palladium hydride species, thus increasing the ethylene yield. Furthermore, X-ray absorption spectroscopy, high-resolution transmission electron microscopy, and C2H4 temperature-programmed desorption studies combined with density-functional theory calculations reveal the existence of a unique Pd local environment, containing subsurface carbon atoms, that produces positive geometric effects on the acetylene conversion reaction. Therefore, tailoring the Pd local environment and electronic properties represents an effective strategy for the fabrication and design of highly active and selective Pd semi-hydrogenation catalysts.

In order to deal with the problems of poor anti-interference, low reconstruction clarity and large errors in the traditional medical image reconstruction methods, we proposed a fuzzy medical images three-dimensional (3D) reconstruction method using quantum algorithm. First of all, a feature matching model of fuzzy medical image was built. Secondly, this study decomposed the edge contour features by using the Gaussian mixture feature matching method, extracted the edge contour vectors of fuzzy medical image, and enhanced the information of fuzzy medical images by adopting the region edge sharpening. Thirdly, this study reorganized the 3D texture structure of images and reconstructed the sparse scattered points according to its texture and detail regions. Finally, we combined with the gray histogram of fuzzy medical images to achieve the adaptive pixel reconstruction of fuzzy medical images, and completed the 3D reconstruction of fuzzy medical images by employing the quantum algorithm. The results show that the proposed method is characterized by high matching degree of image features and balanced distribution of point clouds, and the self-similarity coefficient of the reconstructed texture can reach 0.994; in addition, the SINR value of the reconstruction result can be maintained around 100dB, and it has lower error rate than the traditional method, thereby improving the detection and recognition capability of medical images, and the algorithm has certain practical application.

Boreal peatlands, of which Sphagnum bogs are one of the main types, play essential roles in the terrestrial soil carbon pool. Vegetation phenology is a sensitive indicator that reveals the underlying processes as well as responses to climate change, while currently there remain knowledge gaps in exploring and monitoring the longterm bog vegetation phenology due to insufficient remote sensing application experiences. In this study, we investigated three remotely sensed vegetation phenological parameters, the start of growing season (SOS), the end of growing season (EOS), and the length of growing season (LOS) in two bogs located in norther China by using double-logistic reconstructed MOD13Q1-EVI from 2001 to 2018, which were evaluated by the flux phenology. Also combing with meteorological data to detect interactions between vegetation phenology and climate change. The results showed that remotely sensed EOS had 8-day time lags with flux phenological date, while that outperformed SOS. Bog vegetation generally with a life pattern of SOS at the 108th day of year (doy) and EOS at the 328th doy, though the life cycle of individual vegetation groups varies among different vegetation communities. There was no significant delayed (or extended) trend in each phenological features in bogs. Precipitation and minimum temperature (monthly and annual) were the driving forces for bog vegetation growth (R2 0.9, P < 0.01), and other features presented weaker correlations. Overall, this study determined the remote sensing phenology and climate drivers in two Chinese bogs, we suggested that vegetation phenology alternation should be concerned when carry on ecological processes and carbon dynamics researches in peatlands.

Background Cross-resistance, a phenomenon that a pathogen resists to one antimicrobial compound also resists to one or several other compounds, is one of major threats to human health and sustainable food production. It usually occurs among antimicrobial compounds sharing the mode of action. In this study, we determined the sensitivity profiles of Alternaria alternata, a fungal pathogen which can cause diseases in many crops to two fungicides (mancozeb and difenoconazole) with different mode of action using a large number of isolates (234) collected from seven potato fields across China. Results We found that pathogens could also develop cross resistance to fungicides with different modes of action as indicated by a strong positive correlation between mancozeb and difenoconazole tolerances to A. alternata. We also found a positive association between mancozeb tolerance and aggressiveness of A. alternata, suggesting no fitness penalty of developing mancozeb resistance in the pathogen and hypothesize that mechanisms such as antimicrobial compound efflux and detoxification that limit intercellular accumulation of natural/synthetic chemicals in pathogens might account for the cross-resistance and the positive association between pathogen aggressiveness and mancozeb tolerance. Conclusions The detection of cross-resistance among different classes of fungicides suggests that the mode of action alone may not be an adequate sole criterion to determine what components to use in the mixture and/or rotation of fungicides in agricultural and medical sects. Similarly, the observation of a positive association between the pathogen’s aggressiveness and tolerance to mancozeb suggests that intensive application of site non-specific fungicides might simultaneously lead to reduced fungicide resistance and enhanced ability to cause diseases in pathogen populations, thereby posing a greater threat to agricultural production and human health. In this case, the use of evolutionary principles in closely monitoring populations and the use of appropriate fungicide applications are important for effective use of the fungicides and durable infectious disease management. Electronic supplementary material The online version of this article (10.1186/s12866-019-1574-8) contains supplementary material, which is available to authorized users.

1. The evolution of fungicide resistance in agricultural and natural ecosystems is associated with the biology of pathogens, the chemical property and application strategies of the fungicides. The influence of ecological factors such as host diversity on the evolution of fungicide resistance has been largely overlooked but is highly relevant to social and natural sustainability. In this study, we used an experimental evolution approach to understand how host population heterogeneity may affect the evolution of fungicide resistance in the associated pathogens.2. Potato populations with six levels of genetic heterogeneity were grown in the same field and naturally infected by Phytophthora infestans. Pathogen isolates (similar to 1,200) recovered from the field experiment were molecularly genotyped. Genetically distinct isolates were selected from each population and 142 isolates were assayed for their tolerance to two fungicides differing in the mode of action. Tolerance was determined by calculating the relative growth rate of the isolates in the presence and absence of fungicides and the effective concentration for 50% inhibition.3. The evolution of fungicide resistance in P. infestans was affected by the genetic variation of host populations. Higher potato diversification increased the sensitivity of P. infestans to both fungicides and reduced genetic variation of the pathogen available for the development of fungicide resistance. These mitigating effects are independent of biochemical properties of fungicides and are likely caused by host selection for pathogen strains differing in the ability of fungicide influxes, effluxes or detoxification rather than mutations in fungicide target genes.4. Synthesis and applications. The development of fungicide resistance greatly threatens food security and ecological sustainability, and it is urgent need to develop agricultural practices which can ameliorate this problem. Our results show that potato crop with a higher genetic diversity is associated with a late blight pathogen of higher fungicide sensitivity and lower potential of developing fungicide resistance, indicating that agricultural diversification such as through cultivar mixture can reduce the application dose and frequency of fungicides needed to achieve the same level of disease control, which, in turn, further reduce the selection pressure acting on the pathogen populations and the evolutionary risk of developing fungicide resistance in pathogens. Together with benefits documented in other studies, our results indicate that crop diversification is an eco-friendly approach that not only ameliorate fungicide resistance but also help achieve social and ecological sustainability by balancing the interaction among food security, socio-economic development and ecological resilience and should be promoted.

Biodiversity plays multifaceted roles in societal development and ecological sustainability. In agricultural ecosystems, using biodiversity to mitigate plant diseases has received renewed attention in recent years but our knowledge of the best ways of using biodiversity to control plant diseases is still incomplete. In term of in-crop diversification, it is not clear how genetic diversity per se in host populations interacts with identifiable resistance and other functional traits of component genotypes to mitigate disease epidemics and what is the best way of structuring mixture populations. In this study, we created a series of host populations by mixing different numbers of potato varieties showing different late blight resistance levels in different proportions. The amount of naturally occurring late blight disease in the mixture populations was recorded weekly during the potato growing seasons. The percentage of disease reduction (PDR) in the mixture populations was calculated by comparing their observed late blight levels relative to that expected when they were planted in pure stands. We found that PDR in the mixtures increased as the number of varieties and the difference in host resistance (DHR) between the component varieties increased. However, the level of host resistance in the potato varieties had little impact on PDR. In mixtures involving two varieties, the optimum proportion of component varieties for the best PDR depended on their DHR, with an increasing skewness to one of the component varieties as the DHR between the component varieties increased. These results indicate that mixing crop varieties can significantly reduce disease epidemics in the field. To achieve the best disease mitigation, growers should include as many varieties as possible in mixtures or, if only two component mixtures are possible, increase DHR among the component varieties.

To explore the correlation among gingival thickness (GT), underlying alveolar bone thickness (BT), and other periodontal biotype characteristics in the maxillary anterior.A total of 40 young volunteers with healthy periodontal were involved in this research. The periodontal probe was previously used to divide the gingiva from thick to thin. Two records were measured by cone beam CT (CBCT) GT, which was measured at the cement-enamel junction level; and BT, which was measured at 3 locations: 1, 3, 5 mm below the alveolar crest. Oral and gypsum measurements were used to analyze the associations of the crown width/crown length ratio (CW/CL), the keratinized mucosa width (KM), and the free gingival margin curvature.Significant difference in the GT was observed between the thick and thin biotypes, which were divided by periodontal probe (P0.01). Difference was observed in each periodontal biotype characteristic between the thick (GT≥1 mm) and thin biotypes (GT1 mm) (P0.05). BT was positively associated with GT (r=0.293, P=0.001), CW/CL (r=0.273, P=0.003), KM (r=0.291, P=0.001), and free gingival margin curvature (r=0.290, P=0.001).The transparency of the probing in the sulcus could analyze the GT qualitatively. The thick and thin biotypes have different periodontal biotype characteristics. Compared with individuals with thick biotype, those with thin biotype are susceptible to risk dental aesthetic.目的 运用锥形束CT测量上颌前牙唇侧牙龈厚度与唇侧牙槽骨厚度，通过口内及模型测量牙冠宽长比、角化龈宽度、游离龈缘曲度，分析各牙周生物型特征之间的相关性。方法 选取40位牙周健康的青年志愿者，运用牙周探诊法预先判断受试牙位的牙龈厚薄，运用锥形束CT间接显影方法测量受试者上颌前牙区唇侧釉牙骨质界处牙龈厚度，以及牙槽嵴顶根方1、3、5 mm处牙槽骨厚度，通过口内及模型测量牙冠宽长比、附着龈宽度及游离龈缘曲度。结果 牙周探诊法区分的厚龈型与薄龈型间牙龈厚度的差异有统计学意义（P0.01）。厚龈型（牙龈厚度≥1 mm）与薄龈型（牙龈厚度1 mm）相应的牙周生物型特征之间的差异有统计学意义（P0.05）。上颌前牙唇侧牙龈厚度与牙槽骨厚度呈正相关（r=0.293，P=0.001），与牙冠宽长比呈正相关（r=0.273，P=0.003），与角化龈宽度呈正相关（r=0.291，P=0.001），与游离龈缘曲度呈正相关（r=0.290，P=0.001）。结论 牙周探诊法可用于对牙龈厚薄的快速判断，不同牙周生物型在软硬组织厚度及形态上有差异，相对于厚龈型，薄龈型治疗的美学风险更大。.

Supported single-atom catalysts, which bridge the gap between homogeneous and heterogeneous catalysis, have attained increasing interest because of their unique catalytic properties and behaviors. In this contribution, periodic DFT+U calculations have been carried out to explore the structural stability, catalytic activity, and selectivity of 13 M1–ZnO (M = Mn–Cu, Ru–Ag, and Os–Au) catalysts in propane dehydrogenation (PDH). Calculated results indicate that the doped single atoms show high resistance to sintering on the ZnO surface. Except on Rh1-, Os1-, Ir1-, and Pt1–ZnO(10[1 with combining macron]0), a Lewis acid–base interaction occurs, which would greatly enhance the co-adsorption of a pair of amphoteric species on the oxides. The linear chemisorption energy and transition state energy scaling relations hold well for the C–H and H–H bond activation steps involved in the reaction network. Microkinetic analysis is used to determine the activity trend, and volcano-shaped plots of the turnover frequency for propylene production are obtained, with the formation energies of adsorbed H and 2-propyl used as two reactivity descriptors. By using the activation energy difference between propylene dehydrogenation and desorption as a measure of the catalyst selectivity, it is found that a high selectivity can only be achieved at the expense of catalytic activity. Comparison between the energy barriers for H2 desorption and H2O formation indicates that the reduction of ZnO can be suppressed by single-atom doping. The Mn- and Cu-doped ZnO catalysts are suggested to be good catalyst candidates for PDH with lower cost, increased activity, and improved selectivity and catalytic stability.

New trigeneration system consists of an internal combustion engine, a power and cooling cogeneration system and an absorption heat transformer system. The exhaust gas is recovered by the power and cooling cogeneration subsystem producing the cooling and power. The jacket water is recovered by the absorption heat transformer subsystem producing lowpressure steam. The exergy performance and the energy saving performance which is evaluated by the primary energy saving ratio of the new distributed energy system are analyzed. The effects of the ratio of the output power and cooling of the power and cooling cogeneration subsystem and the generator outlet temperature of the absorption heat transformer subsystem to the primary energy saving ratio are considered. The contributions of the subsystems to the primary energy saving ratio are quantified. The maximum primary energy saving ratio of the new distributed energy system is 15.8%, which is 3.9 percentage points higher than that of the conventional distributed energy system due to the cascade utilization of the waste heat from the internal combustion engine.

Rationally tailored perovskites ABO3 are promising substitutes for expensive noble-metal catalysts in heterogeneous catalysis. In this contribution, the BEEF-vdW + U method has been used to examine the adsorption of H, C, O, and CH3 over (K,Rb,Cs,Sr,Ba)BO3 (B = d-block transition metals) and ARuO3 (A = La to Ho) with various crystal structures. The calculated chemisorption energy of the simple species at the O site scales well with the surface oxygen vacancy formation energy of all the perovskites under consideration, while the trend in the chemisorption energy at the B site can be described by the surface metal vacancy formation energy only over ARuO3. Electronic structure analysis indicates that the perovskites could be classified into several categories according to the splitting and filling of the d and f orbitals of the B- and A-site cations, respectively. In each category, the chemisorption energies at the B site on (K,Rb,Cs,Sr,Ba)BO3 and ARuO3 are also closely related to the strength of the ionic bonding in the perovskites. Hence, the surface oxygen vacancy formation energy can be used as a descriptor to explain the trend in the calculated adsorption energies upon substitution of either B- or A-site cations, which has its origin in the fact that the larger the actual partial charges the oxygen and transition-metal ions carry, the stronger the B–O bond, which in turn weakens and enhances the ability of the O anions to withdraw and the ability of the B cations to donate electrons to the adsorbates, respectively.

The exposed termination of transition-metal oxide surfaces plays a major role in determining the catalyst performance in redox reactions. In this contribution, the surface phase diagrams of LaMO3(001) (M = Sc–Fe) and LaMO3(110) (M = Co–Cu) are constructed by using the DFT+U method. The stabilities of six terminations derived from the stoichiometric MO2 and LaO surfaces are determined over a wide range of temperatures and oxygen partial pressures. The surface phase diagrams are calculated towards the O-rich limit in which the chemical potential of oxygen anions of perovskites equals that of gas-phase oxygen while the chemical potential of M cations is limited by thermodynamic boundary conditions. It is found that the surface phase diagrams are closely related to the reducibility of M cations, which is reflected in the oxygen adsorption energy and oxygen vacancy formation energy on the MO2- and LaO-terminated surfaces and can be measured by the third ionization energies of the M2+ cations. According to the surface phase diagrams, the most stable surface termination is predicted to be of MO2 type for LaMO3 (M = Sc–Fe) and LaO type for LaMO3 (M = Co–Cu) under solid oxide fuel cell operating conditions. Because the M cations become more readily reduced on going from left to right across the period, LaCoO3 may form an oxygen-deficient crystal structure at high temperatures and LaNiO3 and LaCuO3 would be decomposed into oxides containing the transition metals in a lower oxidation state. © 2019. This is the authors' accepted and refereed manuscript to the article. The final authenticated version is available online at: https://doi.org/10.1039/C9CP02288K.

Understanding the oxygen transport behavior in perovskites is of central importance for tailoring their physical and chemical properties to various practical applications. In this contribution, periodic DFT+U calculations have been performed to unravel the electronic origin of the oxygen mobility difference in La-based perovskites involving 3d-block transition metals from Sc through Cu. Calculated results indicate that the perovskites generally exhibit an increased reducibility on going from LaScO3 to LaCuO3, and the exceptionally high oxygen vacancy formation energy in LaFeO3 is due to the significant lowering of the electron exchange stabilization upon reduction. The oxygen migration barrier in the first four perovskites varies from 1.2 to 2.1 eV while that for the later five materials is much lower and lies between 0.4 and 0.9 eV. Electronic structure analysis indicates this abrupt change in the migration barrier can be attributed to the different degrees of charge redistribution on the central transition-metal ion during the migration process. Linear scaling relations are established to show that the oxygen bulk diffusion coefficient is governed essentially by the oxygen concentration rather than by the migration barrier. The actual partial charge on the transition metal or oxygen ion explains the electronic origin of the different oxygen transport properties of La-based perovskites, and the observed trend can be described by using the oxygen vacancy formation energy as a good descriptor. This document is the Accepted Manuscript version of a Published Work that appeared in final form in [Journal of Physical Chemistry C], copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jpcc.8b11249

The flavonoid extract from propolis (FP) has been shown to protect against heart injury induced by isoproterenol. However, the effect of FP on cardiac fibrosis after myocardial infarction (MI) as well as the underlying mechanisms is not known. In the present study, we used biochemical and histological approaches to examine the effects of FP on MI-induced cardiac fibrosis and the related mechanisms in a rat MI model and in angiotensin II- (Ang II-) treated rat cardiac fibroblasts (CFs). In vivo, MI was generated by ligation of the left anterior descending coronary artery of rats, which remained for 4 weeks. Rats were randomly divided into the sham, MI, FP (12.5 mg/kg/d), and MI+FP groups. We found that FP treatment improved heart function, reduced cardiac fibrosis, and downregulated the expression of fibrosis-related factors including collagen I, collagen III, matrix metalloproteinase-2 (MMP-2), MMP-9, transforming growth factor-β1 (TGF-β1), and p-Smad2/3, which coincided with the upregulated expression of silent information regulator 1 (SIRT1) in the hearts of MI rats. Our in vitro experiments showed that FP inhibited the proliferation and migration of primary cultured rat CFs and downregulated the expression of the above-mentioned fibrosis-related factors in Ang II-stimulated CFs. In addition, FP can decrease ROS production induced by MI and Ang II in vivo and vitro. Notably, silencing SIRT1 counteracted the FP-induced effects on CFs treated with Ang II. We conclude that FP inhibits MI-induced cardiac fibrosis through SIRT1 activation and that FP represents a potential promising drug for the treatment of MI patients in the clinic.

Catalyst deactivation by coking is one major problem for propane dehydrogenation (PDH). To develop catalysts with high resistance to coke, the analysis of coke becomes essential. In this work, an analysis procedure is proposed and validated to acquire the detailed locations and compositions of the coke formed on an as-synthesized Pt–Sn/Al2O3 catalyst. This procedure combines high-resolution transmission electron microscopy (HRTEM), FT-IR, Raman, thermogravimetric analysis (TG), and pyrolysis GC-MS; with this procedure, the systematic and quantitative analysis of coke can be achieved. The results show that the coke is located on the metal, in the vicinity of the metal, and on the support. Besides, aliphatics, aromatics, and pregraphite cokes are identified, and they account for 69.0, 4.4, and 26.6 wt %, respectively. Finally, an in situ DRIFT study is performed, and the results show that the aliphatic coke can be transformed into the aromatic coke and this transformation is related to the deep dehydrogenation reactions. © American Chemical Society 2018. This is the authors accepted and refereed manuscript to the article. Locked until 8.6.2019 due to copyright restrictions.

Periodic density functional theory calculations have been performed to examine the effect of oxygen deficiency on the structural stability of Lanthanum-based perovskites (LaMO3), where on-site Coulomb interactions have been addressed by an additional Hubbard-type term. Calculated results indicate that with the exception of LaFeO3, the oxygen vacancy formation energy ( Δ E f o r m a t i o n , v a c ) of LaMO3 (M = Sc - Cu) becomes less positive when moving across the first transition metal period. The first four LaMO3 perovskites have very high oxygen vacancy formation energies and can hardly be reduced under mild conditions, while the other five perovskites exhibit a much greater reducibility. During the formation of the first oxygen vacancy in LaMO3 (M = Mn - Cu), the nearest neighbor transition-metal cations serve as the primary acceptors of the electrons left behind. As oxygen atoms are further removed, square-based pyramidal and tetrahedral coordination geometries appear successively, and an abrupt increase in Δ E f o r m a t i o n , v a c is observed at a specific oxygen deficiency (δ), which defines the maximum possible δ in the perovskite structures. Under this definition, the M3+ cations (M = Mn - Ni) can be possibly reduced to M2+ while LaCuO3 may lose at most one lattice oxygen atom per formula unit before it is deactivated.

Hepatocytic stem cells (HSCs) have inhibitory effects on hepatocarcinoma cells. The present study investigated the effects of HSC activity in hepatocarcinoma cells in vitro. A Transwell co-culture system of hepatocytic precursor (stem-like) WB-F344 cells and hepatoma CBRH-7919 cells was used to assess HSC activity in metastasized hepatoma cells in vitro. Nude mouse xenografts were used to assess HSC activity in vivo. Co-culture of hepatoma CBRH-7919 cells with WB-F344 cells suppressed the growth and colony formation, tumor cell migration and invasion capacity of CBRH-7919 cells. The nude mouse xenograft assay demonstrated that the xenograft size of CBRH-7919 cells following co-culture with WB-F344 cells was significantly smaller compared with that of control cells. Furthermore, the expression levels of the epithelial markers E-cadherin and β-catenin were downregulated, while the mesenchymal markers α-SMA and vimentin were upregulated. Co-culture of CBRH-7919 cells with WB-F344 cells downregulated NF-κB and phospho-Akt expression. In conclusion, hepatocytic precursor (stem-like) WB-F344 cells inhibited the growth, colony formation and invasion capacity of metastasized hepatoma CBRH-7919 cells in vitro and in vivo by downregulating Akt/NF-κB signaling.

Propolis, a traditional medicine, has been widely used for a thousand years as an anti-inflammatory and antioxidant drug. The flavonoid fraction is the main active component of propolis, which possesses a wide range of biological activities, including activities related to heart disease. However, the role of the flavonoids extraction from propolis (FP) in heart disease remains unknown. This study shows that FP could attenuate ISO-induced pathological cardiac hypertrophy (PCH) and heart failure in mice. The effect of the two fetal cardiac genes, atrial natriuretic factor (ANF) andβ-myosin heavy chain (β-MHC), on PCH was reversed by FP. Echocardiography analysis revealed cardiac ventricular dilation and contractile dysfunction in ISO-treated mice. This finding is consistent with the increased heart weight and cardiac ANF protein levels, massive replacement fibrosis, and myocardial apoptosis. However, pretreatment of mice with FP could attenuate cardiac dysfunction and hypertrophyin vivo. Furthermore, the cardiac protection of FP was suppressed by the pan-PI3K inhibitor wortmannin. FP is a novel cardioprotective agent that can attenuate adverse cardiac dysfunction, hypertrophy, and associated disorder, such as fibrosis. The effects may be closely correlated with PI3K/AKT signaling. FP may be clinically used to inhibit PCH progression and heart failure.

OBJECTIVE CD4 CD25 T regulatory (Treg) cells are a population of T cells which suppress an overactive immune system. CCR4 is a chemokine receptor involved in the recruitment of lymphocytes. Nasopharyngeal carcinoma (NPC) is resistant to immunosurveillance, owing to the increased number of tumor-infiltrating Treg cells which are recruited to the tumor by CCR4. METHODS The percentage of CD4+CD25+ Treg cells and CCR4+ cells in tissue or peripheral blood (PB) lymphocytes of patients with untreated NPC or normal subjects was analysed by flow cytometry. RESULTS In both tissue and PB lymphocytes, the percentage of CD4+CD25+ Treg cells and CCR4+cells was significantly elevated in patients with NPC in comparison with that in the normal tissue of controls. Furthermore, in the patients with NPC, a higher percentage of CD4+CD25+ Treg cells was found in the tumor-infiltrating (TI) lymphocyte population than in the PB population. In the NPC patient group, a general trend towards an increased percentage of TI Treg cells was found in the patients with advanced stage NPC. The number of CD4+CD25+ Treg cells was positively related to the number of CCR4+ cells in the tumor and in the PB of the patients with NPC, while the number of CD4+CD25+ Treg cells was negatively related to the number of CD4+CD25 － T cells. CONCLUSION Immunosuppression was observed in NPC, especially at the tumor sites. CD4+CD25+ Treg cells may suppress CD4+CD25 － T cells. CCR4 may have an important role in the recruitment of CD4+CD25+ Treg cells to tumor sites, thus causing resistance to immunosurveillance.

Hepatic lymphangiomas, malformations of the liver lymphatic system, are extremely rare conditions in adults. A 41-year-old man presented with right upper abdominal pain for 6 months was introduced in this report. Ultrasound (US) and computed tomography (CT) scan demonstrated a giant cystictumor with a pedunculatedextrahepatic growth pattern. Due to diagnostic uncertainty, a partial hepatectomy was performed and pathological results confirmed the diagnosis of solitary hepatic lymphangioma. In this article, we reviewed the clinical and pathology features, preoperative diagnostic challenges, and treatments of hepaticlymphangiomas.

The effect of the amounts of initiator, emulsifier, and molecular weight regulator on the styrene butadiene rubber performance was investigated, based on the industrial original formula. It was found that the polymerization rate was increased with the increased dosage of initiator and emulsifier, and together with replenishing molecular weight regulator will make the Mooney viscosity of rubber meet the national standard when the conversion rate reaches 70%. The backpropagation neural network was trained by the original formula and ameliorated formula on the basis of Levenberg-Marquardt algorithm, and the relative error between the simulation results and experimental data is less than 1%. The good consistency shows that the BP neural network could predict the product performances in different formula conditions. It would pave the way for adjustment of the SBR formulation and prediction of the product performances.