Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantiall...Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantially enhance land resources.This study highlights the necessity for a precise correlation between land development initiatives and constraints in order to optimize efficiency and enhance the effectiveness of such projects,with the core being the seamless integration of land development engineering and techniques to eliminate agricultural constraints.This study employs a systems engineering approach to classify improvement factors into mobile and fixed categories,elucidating the integration methods of constraint factors.Adhering to the Wooden Barrel Principle,these constraints were rigorously analyzed based on soil quality,land topography,water availability,and agricultural infrastructure.An innovative method of engineering type combination is proposed,which effectively explains the correlation between natural factors combination,project type combination,and target factors combination.It provides a convenient way for the selection of barren grassland development projects and lays a foundation for land planning,development project establishment,program selection,engineering design,and budget preparation.Taking Tang County of China as an example,it is divided into 19 factor improvement areas,a quick reference table of engineering types is established,and 14 main types of engineering combinations are obtained,which lays a foundation for the application of theoretical framework in practice.展开更多
The inner hole parts played an oriented or supporting role in engineering machinery and equipment,which are prone to appear surface damages such as wear,strain and corrosion. The precise pulse plasma arc powder weldin...The inner hole parts played an oriented or supporting role in engineering machinery and equipment,which are prone to appear surface damages such as wear,strain and corrosion. The precise pulse plasma arc powder welding method is used for surface damage repairing of inner hole parts in this paper. The working principle and process of the technology are illustrated,and the microstructure and property of repairing layer by precise pulse plasma powder welding and CO2 gas shielded welding are tested and observed by microscope,micro hardness tester and X-ray residual stress tester etc. Results showed that the substrate deformation of thin-walled inner hole parts samples by precise pulse plasma powder welding is relatively small. The repair layer and substrate is metallurgical bonding,the transition zones( including fusion zone and heat affected zone) are relatively narrow and the welding quality is good. It showed that the thin-walled inner hole parts can be repaired by this technology and equipment.展开更多
Previous studies have demonstrated a strong association between carbamazepine（CBZ）-induced Stevens-Johnson syndrome（SJS） and HLA-B 1502 in Han Chinese. Here, we extended the study of HLA-B 1502 susceptibility to t...Previous studies have demonstrated a strong association between carbamazepine（CBZ）-induced Stevens-Johnson syndrome（SJS） and HLA-B 1502 in Han Chinese. Here, we extended the study of HLA-B 1502 susceptibility to two different antiepileptic drugs, oxcarbazepine（OXC） and phenobabital（PB）. In addition, we genotyped HLA-B 1511 in a case of CBZ-induced SJS with genotype negative for HLA-B 1502. The presence of HLA-B 1502 was determined using polymerase chain reaction with sequence-specific primers（PCR-SSP）. Moreover, we genotyped HLA-B 1502 in 17 cases of antiepileptic drugs（AEDs）-induced cutaneous adverse drug reactions（cADRs）, in comparison with AEDs-tolerant（n=32） and normal controls（n=38） in the central region of China. The data showed that HLA-B 1502 was positive in 5 of 6 cases of AEDs-induced SJS（4 CBZ, 1 OXC and 1 PB）, which was significantly more frequent than AEDs-tolerant（2/32, 18 CBZ, 6 PB and 8 OXC） and normal controls（3/38）. Compared with AEDs-tolerant and normal controls, the OR for patients carrying the HLA-B 1502 with AEDs-induced SJS was 6.25（95% CI： 1.06–36.74） and 4.86（95% CI： 1.01–23.47）. The sensitivity and specificity of HLA-B 1502 for prediction of AEDs-induced SJS were 71.4%. The sensitivity and specificity of HLA-B 1502 for prediction of CBZ-induced SJS were 60% and 94%. HLA-B 1502 was not found in 11 children with maculopapular exanthema（MPE）（n=9） and hypersensitivity syndrome（HSS）（n=2）. However, we also found one case of CBZ-induced SJS who was negative for HLA-B 1502 but carried HLA-B 1511. It was suggested that the association between the CBZ-induced SJS and HLA-B 1502 allele in Han Chinese children can extend to other aromatic AEDs including OXC and PB related SJS. HLA-B 1511 may be a risk factor for some patients with CBZ-induced SJS negative for HLA-B 1502.展开更多
On May 24-29,2019,a bloom occurring in Pingtan coastal areas of Fujian Province caused mass mortality of cage-cultured fish(Plectorhinchus cinctus and Pagrosomus major).During the bloom,two major causative organisms w...On May 24-29,2019,a bloom occurring in Pingtan coastal areas of Fujian Province caused mass mortality of cage-cultured fish(Plectorhinchus cinctus and Pagrosomus major).During the bloom,two major causative organisms were present:Prorocentrum donghaiense(at a concentration of 1.46×10^7 cells/L)and an unknown naked dinoflagellate(4.58×10^6 cells/L).The naked dinoflagellate was isolated and cultured in this study,and its morphological features were examined using light microscopy and scanning electron microscopy.The large subunit(LSU)of the rRNA gene and the internal transcribed spacer(ITS)region of the naked dinoflagellate were also sequenced for field bloom samples and lab culture strains(PT-A and PT-B).On the basis of its morphological characteristics and molecular sequences,the unknown naked dinoflagellate was identified as Karlodinium digitatum.According to the phylogenetic analysis,the Karl.digitatum was most closely related to Karlodinium australe and Karlodinium armiger,and the three species clustered into a single clade of Karlodinium with bootstrap/posterior probability values of 95%/0.99 and 86%/0.99 inferred from LSU and ITS sequences,respectively.Karl.digitatum was first reported as Karenia digitata,a new harmful algal species bloomed in Hong Kong,China,in 1998.In present study,we gave a detailed morphological and phylogenetic description of Karl.digitatum and submitted the molecular sequences of this species to GenBank for the first time.展开更多
A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c ...A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I 】 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.展开更多
AIM To explore the anti-tumor effects of esophageal cancerrelated gene 2(ECRG2) in combination with cisplatin(DDP) in DDP-resistant esophageal cancer cells(EC9706/DDP).METHODS A drug-resistant cell model was establish...AIM To explore the anti-tumor effects of esophageal cancerrelated gene 2(ECRG2) in combination with cisplatin(DDP) in DDP-resistant esophageal cancer cells(EC9706/DDP).METHODS A drug-resistant cell model was established, with EC9706/DDP cells being treated with ECRG2 and/or DDP. Cell viability was examined by MTT assay. The rate of cell apoptosis was determined by flow cytometry. The mR NA expression levels of proliferating cell nuclear antigen(PCNA), metallothionein(MT), and p53 were determined by RT-PCR and PCNA, while MT and p53 protein expression levels were determined by western blotting.RESULTS The anti-proliferative effect of ECRG2 in combination with DDP was superior when compared to ECRG2 or DDP alone. The inhibition rate for the combination reached its peak(51.33%) at 96 h. The early apoptotic rates of the control, ECRG2 alone, DDP alone, and ECRG2 plus DDP groups were 5.71% ± 0.27%, 12.68% ± 0.61%, 14.15% ± 0.87%, and 27.96% ±0.36%, respectively. Although all treatment groups were significantly different from the control group(P < 0.05), the combination treatment of ECRG2 plus DDP performed significantly better when compared to either ECRG2 or DDP alone(P < 0.05). The combination of ECRG2 and DDP significantly upregulated p53 m RNA and protein levels and downregulated PCNA m RNA and protein levels compared to ECRG2 or DDP alone(P < 0.05). However, no changes were seen in the expression of MT mR NA or protein.CONCLUSION ECRG2 in combination with DDP can inhibit viability and induce apoptosis in esophageal cancer DDP-resistant cells, possibly via upregulation of p53 expression and downregulation of PCNA expression. These findings suggest that the combination of ECRG2 and DDP may be a promising strategy for the clinical treatment of esophageal cancers that are resistant to DDP.展开更多
The dinoflagellate genus K arenia is known for recurrent harmful blooms worldwide. However, species diversity of the genus is generally overlooked owing to the difficulty of identifying small unarmored dinoflagellates...The dinoflagellate genus K arenia is known for recurrent harmful blooms worldwide. However, species diversity of the genus is generally overlooked owing to the difficulty of identifying small unarmored dinoflagellates. We have established four clonal cultures of K arenia longicanalis isolated from the type locality, Hong Kong harbor(strain HK01) and other three locations along the Chinese coasts(strains YB01, DT01, and NJ01). The morphology of the strain was studied by light and scanning electron microscopy(LM and SEM) and the pigment composition analyzed by high-performance liquid chromatography. We provide the first molecular data of K. longicanalis based on the large subunit(LSU) rRNA gene sequence and internal transcribed spacer(ITS). The four strains showed identical LSU rDNA sequences with a similarity of 99.4% to the holotype of K arenia umbella(strain KUTN05) from Australia. In the ITS phylogeny, the sequence of K. umbella branched between the Chinese strains of K. longicanalis. A careful comparison of the morphology of K. longicanalis and K. umbella reveals the similarity in the diagnostic characters. Diff erences may appear due to the sample treatment for SEM. We conclude that K. umbella is a junior synonym of K. longicanalis.展开更多
A novel europium（Ⅲ） coordination polymer, [Eu3（pydc）3（SO4）（H2O）5（ox）0.5]·3H2O（1, H2ox = oxalic acid, H2 pydc = pyridine-2,6-dicarboxylic acid）, has been synthesized hydrothermally from the self-assem...A novel europium（Ⅲ） coordination polymer, [Eu3（pydc）3（SO4）（H2O）5（ox）0.5]·3H2O（1, H2ox = oxalic acid, H2 pydc = pyridine-2,6-dicarboxylic acid）, has been synthesized hydrothermally from the self-assembly of lanthanide ions（Eu3＋） with the flexible oxalic acid and the rigid pyridine-2,6-dicarboxylic acid ligands, respectively. It crystallizes in the triclinic system, space group P1 with a = 11.225（4）, b = 12.390（5）, c = 13.752（5）A, α = 89.228（7）, β = 71.142（6）, γ = 75.552（6）°, Dc = 2.317 g/cm^3, μ = 5.480 mm^-1, F（000） = 1150, Z = 2, the final R = 0.0351 and w R = 0.0949 for 8782 observed reflections with I 〉 2σ（I）. Structural analysis reveals that complex 1 exhibits a three-dimensional metal-organic framework via π-π stacking interactions. In addition, complex 1 displays a red fluorescence emission in the solid state at room temperature, which corresponds to the 5D0 → 7F2 transition of Eu3＋ ions.展开更多
This study investigated the effects of miRNA-155 on malignant biological characteristics of NK/T-cell lymphoma cell lines and the possible mechanism. The expression of miRNA-155 was detected in lymphoma cell lines fro...This study investigated the effects of miRNA-155 on malignant biological characteristics of NK/T-cell lymphoma cell lines and the possible mechanism. The expression of miRNA-155 was detected in lymphoma cell lines from different sources （SNK-6, YTS, Jurkat and DOHH2） by real-time PCR. Lentiviral vectors （pLL3.7） that could overexpress or downexpress miRNA-155 were constructed. Recombinant lentiviral particles were prepared and purified, and their titers determined. The expression of miRNA-155 in the infected SNK-6 cells and the cell proliferation were detected by PCR and CCK-8, respectively. Flow cytometry was used to determine the apoptosis of infected SNK-6 cells. The target of miRNA155 was predicted from Targetscan website. The effect of miRNA155 on FOXO3a expression was examined by Western blotting. The results showed that among the human NK/T-cell lymphoma cell lines SNK-6, YTS, Jurkat and DOHH2, the expression of miRNA-155 was highest in SNK-6. The infection efficiency of the recombinant lentivirns in SNK-6 was more than 70% at multiplicity of infection （MOI） of 100. The expression of miRNA-155 was significantly increased in SNK-6 cells infected by lentivirus vectors with high expression of miRNA-155 （4 times higher than the control group）, and profoundly decreased in those infected with lentivirnses with low expression of miRNA-155. The proliferation of letivirns-infected SNK-6 cells was decreased as the expression of miRNA-155 reduced. The apoptosis rate was increased with the reduction in the expression of miRNA-155. FOXO3a was found to be a possible target of miRNA155, as suggested by Targetscan website. Western blotting showed that the expression of FOXO3a was significantly elevated in SNK-6 cells with miRNA-155 inhibition. It was concluded that reduction in miRNA-155 expression can inhibit the proliferation of SNK-6 lymphoma cells and promote their apoptosis, which may be associated with regulation of FOXO3a gene.展开更多
Over the past decades,jellyfish occurred increasingly and abundantly in coastal areas worldwide.Usually,biomass of jellyfish,especially when they bloom,can be determined by visual counting.However,tiny individuals of ...Over the past decades,jellyfish occurred increasingly and abundantly in coastal areas worldwide.Usually,biomass of jellyfish,especially when they bloom,can be determined by visual counting.However,tiny individuals of jellyfish(e.g.,planulae,polyps,and ephyrae)are difficult to detect in the field.In this study,species-specific quantitative real-time PCR assays(qPCR)(SYBR Green I)targeting the mitochondrial 16S rDNA(mt-16S rDNA)of jellyfish were developed and were used to estimate the distribution and seasonal fluctuations of four jellyfish species(Nemopilema nomurai,Cyanea nozakii,Rhopilema esculentum,and Aurelia coerulea)in Jiaozhou Bay(JZB),China in 2013.The mt-16S rDNA of A.coerulea and N.nomurai was detected in most of the survey months and it peaked in July(1.03×10^(4) copies/L)and September(1.08×10^(6) copies/L),respectively.The mt-16S rDNA of C.nozakii occurred from August to October only with monthly mean values of 7.18-46.17 copies/L and was mainly located from the middle part to the outer part of the bay.The mt-16S rDNA of R.esculentum was the least abundant among the four species and was detected in only one sample(B2 station in March),with a value of 88.49 copies/L.The Spearman correlation test revealed that phytoplankton biomass was significantly and positively correlated with the mt-16S rDNA abundance of A.coerulea(R=0.37,P<0.01)and negatively with the mt-16S rDNA of N.nomurai(R=-0.36,P<0.01).The qPCR assay will enable the identification and quantification of jellyfish species in their whole life history and can be used as an approach in combination of the traditional jellyfish survey.展开更多
Objective To identify significant factors related to the apolipoprotein B/apolipoprotein A1 （apoB/A1） ratio and investigate the association between the apoB/A1 ratio and metabolic syndrome （MS） in polycystic ovary...Objective To identify significant factors related to the apolipoprotein B/apolipoprotein A1 （apoB/A1） ratio and investigate the association between the apoB/A1 ratio and metabolic syndrome （MS） in polycystic ovary syndrome （PCOS） women. Methods Totally 307 subjects with PCOS were collected and recruited fulfilling the revised 2003 Rotterdam diagnostic criteria. MS was diagnosed by the National Cholesterol Education Program-Adult treatment Panel （NCEP-ATP） III criteria. Results The prevalence of MS in PCOS women was 31.6%, whose average age was 26.2 ___＋ 5.2 years. The apoB/A1 ratio was significantly correlated with age, body mass index （BM1）, waist circumference （WC）, hip circumference, waist-to-hip ratio, blood pressure, metabolic abnormalities, sex hormone binding globulin （SHBG）, and free androgen index. In addition, SHBG had a significant association with all five component risk of MS. The increasing apoB/A1 ratio was associated with the prevalence of MS and was one of the risk factors of MS. Conclusion SHBG was considered as an additional potential factor in predicting the metabolic abnormity in PCOS women. The apoB/A1 ratio is associated with SHBG and might be an indicator of MS in PCOS women.展开更多
Effect of divalent dopants, Zn2＋ ion, on the high-order photon avalanche （PA） upconversion （UC） emission of Er3＋ doped BiOCl microcrystals was investigated. XRD results indicated that Zn2＋ ion dopants would mos...Effect of divalent dopants, Zn2＋ ion, on the high-order photon avalanche （PA） upconversion （UC） emission of Er3＋ doped BiOCl microcrystals was investigated. XRD results indicated that Zn2＋ ion dopants would mostly enter into the lattice space at low and moderate doping concentration, and began to substitute Bi3＋ ion gradually at heavily doping level. Under exaction at 980 nm, the PA UC of violet, green and red emission of Er3＋ ions could be observed, and the UC emission intensity increased with increasing the Zn2＋ addition below 8 mol.%, then decreased with further addition. Power dependence study showed that the dopant concentration of Zn2＋ had no obviously negative effect on the occurrence of PA emission. On the bases of results investigated herein, we considered that the lattice distortion by Zn2＋ doping could not directly change the special PA emission of BiOCI：Er3＋, but would improve the emission intensity when used as lattice modifier.展开更多
The exploration of novel long lasting red phosphors is still of importance due to expected commercial applications and scientific interests. In this work, we reported the red long lasting phosphorescence（LLP） from E...The exploration of novel long lasting red phosphors is still of importance due to expected commercial applications and scientific interests. In this work, we reported the red long lasting phosphorescence（LLP） from Eu^3＋ doped BiOCl semiconductor polycrystals. The LLP property of the red phosphor is relatively weak due to less trap density, but the excitation band of LLP stems from the energy gap transition of semiconductor, offering experimental evidence for energy transfer between BiOCl semiconductor and Eu^3＋ ions. Although the afterglow duration of Eu^3＋ doped BiOCl was short temporarily, this work may open a novel kind of red LLP phosphors.展开更多
The purpose of this study was to compare the functional outcomes, psychological impact, and complication rates associated with external fixation and volar or dorsal plating in relation to the functional parameters fol...The purpose of this study was to compare the functional outcomes, psychological impact, and complication rates associated with external fixation and volar or dorsal plating in relation to the functional parameters following treatment of intra-articular fractures of the distal radius （IFDR） in patients older than 65 years. We hypothesized that using volar or dorsal plating would improve functional outcomes, but that it would be associated with more complications and equivalent functional outcomes when compared with the external fixation group. A total of 123 consecutive patients suffering from IFDR were recruited into the study. The patients were measured for clinical, radiological, and psychosocial functioning outcomes and were followed up after I week and 3, 6 and 12 months. After 3 months, the plating group had better pronation （P = 0.001）, supination, （P = 0.047） and extension （P = 0.043） scores. These differences were somewhat attenuated by 6 months and disappeared at I year. The plating group had a greater occurrence of wound infection （P = 0.043）, tendonitis, （P = 0.024） and additional surgery compared with the external fixation group. The only TNO-AZL Adult Quality of Life scores in the plating group that were lower than those in the external fixation group were in the ＂gross motor＂ category （walking upstairs, bending over, walking 500 yards; P = 0.023）. Internal fixation was more advantageous than external fixation in the early rehabilitation period; after I year the outcomes were similar. The plating group showed significantly higher levels of wound infection and tendonitis and had a greater need for additional surgeries.展开更多
Abstract On May 24–29,2019,a harmful algal bloom occurred in Pingtan coastal areas,Fujian,southeast China,and caused mass mortality of cage-cultured fi sh.Two clonal cultures of an unknown naked dinofl agellate were ...Abstract On May 24–29,2019,a harmful algal bloom occurred in Pingtan coastal areas,Fujian,southeast China,and caused mass mortality of cage-cultured fi sh.Two clonal cultures of an unknown naked dinofl agellate were set up from seawater samples taken during the bloom.The cultures were examined for morphological features,ultrastructure characters,photosynthetic pigments,the large subunit(LSU)of the rRNA gene,and the internal transcribed spacer(ITS)sequences,as well as acute toxicity analysis.The cell was unarmored,small-sized,and ovoid,and was characterized by elaborate striations on the epicone and hypocone.The nucleus was large,ellipsoid to oval or kidney-shaped,and centrally located in the cell.A long linear apical groove originated above the sulcus in the ventral epicone and extended to the dorsal side.An elongate,slit-like“ventral pore”was located on the left of the epicone,well away from the apical groove.The chloroplasts were yellowish brown,numerous,band like,and irregularly distributed in the cell periphery.Fucoxanthin was the main accessory pigment composition.Phylogeny topology reconstructed on partial LSU rDNA showed that the unknown dinofl agellate branched as a sister species to Karlodinium sp.(strain IFR981&IFR797,from France)and Karlodinium corrugatum(strain KDGSO08,from Australia),with genetic divergences of 0.6%and 3.3%,respectively.Based on the morphological and molecular phylogenetic analysis,we describe the novel dinofl agellate as Karlodinium elegans sp.nov.A toxicity assay revealed that the clonal culture of K.elegans(strain PTB601)had no adverse eff ect on brine shrimp(Artemia salina)and marine medaka(Oryzias melastigma),indicating it may not be a toxic species.展开更多
A new epidemic SIRS model with discrete delay on scale-free network is presented. We give the formula of the basic reproductive number for the model and prove that the disease dies out when the basic reproductive numb...A new epidemic SIRS model with discrete delay on scale-free network is presented. We give the formula of the basic reproductive number for the model and prove that the disease dies out when the basic reproductive number is less than unity, while the disease is uniformly persistent when the basic reproductive number is more than unity. Numerical simulations are given to demonstrate the main results.展开更多
Unemployment is one of the major vices in our contemporal society, which weigh greatly on the economy of such nation. It is also, a fact that knowing ones enemy before battle gives 50 per cent chance of victory;thus, ...Unemployment is one of the major vices in our contemporal society, which weigh greatly on the economy of such nation. It is also, a fact that knowing ones enemy before battle gives 50 per cent chance of victory;thus, this research aimed at providing understanding about dynamics of unemployment with consideration for retirement and possible control criterion. And the objectives are;formulation of mathematical model using the concept of deterministic model and mathematical epidemiology;then, model analysis. The model analysis includes, a numerical semi-analytical scheme for investigating validity of analytical solutions. The result of the analysis were that: 1) the model was mathematically well-pose and biologically meaningful 2) two equilibria points exist, and 3) a threshold for recruitment from the pool of unemployment, assuring victory in the fight against unemployment was also, obtained. The threshold is required to be well managed in order to win the battle against the socio-vice (unemployment) in the contemporary society. In addition, variational iterative method (VIM) is the numerical semi-analytic scheme employed to solve the model;thus, the approximate solution gave a practical meaningful interpretation supporting the analytical results and proof of verdict of assumptions of the model. The article concluded with three points;everyone has roles to play to curtail the socio-menace, beseech government and policy makers to look kindly, and create policy(ies) to sustain population growth, and the retiree should also, plan live after service, because over dependence on pension scheme could be died before death because of corruption in the scheme.展开更多
A novel Dy^（3＋） coordination compound,（H_2pipz）（H_3O）[Dy（pydc）_3]·11H_2O（1,pipz = piperazine and H_2pydc = pyridine-2,6-dicarboxylic acid）,has been hydrothermally synthesized and characterized by X-ray...A novel Dy^（3＋） coordination compound,（H_2pipz）（H_3O）[Dy（pydc）_3]·11H_2O（1,pipz = piperazine and H_2pydc = pyridine-2,6-dicarboxylic acid）,has been hydrothermally synthesized and characterized by X-ray single-crystal diffraction,elemental analysis. It is interesting that the packing structure of compound 1 contains 22-core water clusters. Compound 1 is extended into a threedimensional supramolecular structure via O···H···O hydrogen bonding interactions. Furthermore,the luminescent property of compound 1 was also investigated.展开更多
Two kinds of 2.5D deep straight-joint structure ultra-high molecular weight polyethylene（UHMWPE）（twisted and original） fibers woven fabric reinforced epoxy resin composites were prepared by the hand lay-up method....Two kinds of 2.5D deep straight-joint structure ultra-high molecular weight polyethylene（UHMWPE）（twisted and original） fibers woven fabric reinforced epoxy resin composites were prepared by the hand lay-up method. Subsequently, the flexural property, microstructures, and failure mechanisms of the composites were also investigated. The average flexural strength of 2.5D deep bend-joint structure twisted fiber and original fiber woven fabric composites were 176.66 MPa and 204.45 MPa, respectively. The results of the characteristics indicated that the twist was the main factor which affected the flexural performance. Flexural property vitally relied on the strength of the fiber itself. Twist decreased the strength of the yarns, which meant that when the mechanical property of woven fabric reinforced composites was improved, the yarns must be kept straight in the woven fabric. The study are extremely valuable to guide the improvement of the mechanical property of the woven fabric reinforced composites.展开更多
Previous Background: Hemodynamic factors, like blood pressure, have been established to be major determinants of cardiac left ventricular structure. However, several factors other than blood pressure to influence card...Previous Background: Hemodynamic factors, like blood pressure, have been established to be major determinants of cardiac left ventricular structure. However, several factors other than blood pressure to influence cardiac mass have been implicated. When we did medical survey, cardiac left ventricular mass index (LVMI) of one ethnic group that had higher blood pressure was found to be smaller than that of the other ethnic groups with a lower blood pressure. Such contradicted data from the present study were analyzed combining blood pressure, LVMI and chemical parameters obtained from blood and urine. Methods: In a medical survey conducted in Xinjiang, China, 279 people (65 - 70 years old) from three ethnic groups (Kazakh, Uygur and Han) from two separated regions provided blood and urine samples and underwent echocardiography and 24-h ambulatory blood pressure monitoring (ABPM). Results: Systolic and diastolic blood pressure obtained from ABPM and urinary sodium excretion values were significantly higher in Kazakh than that in Uygur and Han. However, LVMI in Kazakh was lower than that in other 2 groups. Plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were significantly lowest in Kazakh. The values of LVMI in all ethnic groups were positively related to both blood pressure and PAC. An inverse correlation was identified between PAC and urinary sodium excretion value. Conclusion: Although higher blood pressure in Kazakh subjects, their LVMI was lower than those of Uygur and Han, whose blood pressure was lower than that in Kazakh. These results suggest that blood pressure is not always a determinant for LVMI value. There is a possibility that relatively lower PAC resulted from higher sodium intake suppressed the rise in LVMI caused by higher blood pressure in Kazakh.展开更多
基金funded by Science and Technology Project of Hebei Education Department[QN2023085].
文摘Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantially enhance land resources.This study highlights the necessity for a precise correlation between land development initiatives and constraints in order to optimize efficiency and enhance the effectiveness of such projects,with the core being the seamless integration of land development engineering and techniques to eliminate agricultural constraints.This study employs a systems engineering approach to classify improvement factors into mobile and fixed categories,elucidating the integration methods of constraint factors.Adhering to the Wooden Barrel Principle,these constraints were rigorously analyzed based on soil quality,land topography,water availability,and agricultural infrastructure.An innovative method of engineering type combination is proposed,which effectively explains the correlation between natural factors combination,project type combination,and target factors combination.It provides a convenient way for the selection of barren grassland development projects and lays a foundation for land planning,development project establishment,program selection,engineering design,and budget preparation.Taking Tang County of China as an example,it is divided into 19 factor improvement areas,a quick reference table of engineering types is established,and 14 main types of engineering combinations are obtained,which lays a foundation for the application of theoretical framework in practice.
文摘The inner hole parts played an oriented or supporting role in engineering machinery and equipment,which are prone to appear surface damages such as wear,strain and corrosion. The precise pulse plasma arc powder welding method is used for surface damage repairing of inner hole parts in this paper. The working principle and process of the technology are illustrated,and the microstructure and property of repairing layer by precise pulse plasma powder welding and CO2 gas shielded welding are tested and observed by microscope,micro hardness tester and X-ray residual stress tester etc. Results showed that the substrate deformation of thin-walled inner hole parts samples by precise pulse plasma powder welding is relatively small. The repair layer and substrate is metallurgical bonding,the transition zones( including fusion zone and heat affected zone) are relatively narrow and the welding quality is good. It showed that the thin-walled inner hole parts can be repaired by this technology and equipment.
基金supported by a grant from Clinical Scientific Research of Wuhan Sanitary Bureau(No.WX11C26)research fund from Janssen Research Council of China(No.JRCC2011-01)
文摘Previous studies have demonstrated a strong association between carbamazepine（CBZ）-induced Stevens-Johnson syndrome（SJS） and HLA-B 1502 in Han Chinese. Here, we extended the study of HLA-B 1502 susceptibility to two different antiepileptic drugs, oxcarbazepine（OXC） and phenobabital（PB）. In addition, we genotyped HLA-B 1511 in a case of CBZ-induced SJS with genotype negative for HLA-B 1502. The presence of HLA-B 1502 was determined using polymerase chain reaction with sequence-specific primers（PCR-SSP）. Moreover, we genotyped HLA-B 1502 in 17 cases of antiepileptic drugs（AEDs）-induced cutaneous adverse drug reactions（cADRs）, in comparison with AEDs-tolerant（n=32） and normal controls（n=38） in the central region of China. The data showed that HLA-B 1502 was positive in 5 of 6 cases of AEDs-induced SJS（4 CBZ, 1 OXC and 1 PB）, which was significantly more frequent than AEDs-tolerant（2/32, 18 CBZ, 6 PB and 8 OXC） and normal controls（3/38）. Compared with AEDs-tolerant and normal controls, the OR for patients carrying the HLA-B 1502 with AEDs-induced SJS was 6.25（95% CI： 1.06–36.74） and 4.86（95% CI： 1.01–23.47）. The sensitivity and specificity of HLA-B 1502 for prediction of AEDs-induced SJS were 71.4%. The sensitivity and specificity of HLA-B 1502 for prediction of CBZ-induced SJS were 60% and 94%. HLA-B 1502 was not found in 11 children with maculopapular exanthema（MPE）（n=9） and hypersensitivity syndrome（HSS）（n=2）. However, we also found one case of CBZ-induced SJS who was negative for HLA-B 1502 but carried HLA-B 1511. It was suggested that the association between the CBZ-induced SJS and HLA-B 1502 allele in Han Chinese children can extend to other aromatic AEDs including OXC and PB related SJS. HLA-B 1511 may be a risk factor for some patients with CBZ-induced SJS negative for HLA-B 1502.
基金Supported by the National Key R&D Program of China(No.2017YFC1404301)the National Natural Science Foundation of China(No.41606175)the Beijing Natural Science Foundation(No.8194059)。
文摘On May 24-29,2019,a bloom occurring in Pingtan coastal areas of Fujian Province caused mass mortality of cage-cultured fish(Plectorhinchus cinctus and Pagrosomus major).During the bloom,two major causative organisms were present:Prorocentrum donghaiense(at a concentration of 1.46×10^7 cells/L)and an unknown naked dinoflagellate(4.58×10^6 cells/L).The naked dinoflagellate was isolated and cultured in this study,and its morphological features were examined using light microscopy and scanning electron microscopy.The large subunit(LSU)of the rRNA gene and the internal transcribed spacer(ITS)region of the naked dinoflagellate were also sequenced for field bloom samples and lab culture strains(PT-A and PT-B).On the basis of its morphological characteristics and molecular sequences,the unknown naked dinoflagellate was identified as Karlodinium digitatum.According to the phylogenetic analysis,the Karl.digitatum was most closely related to Karlodinium australe and Karlodinium armiger,and the three species clustered into a single clade of Karlodinium with bootstrap/posterior probability values of 95%/0.99 and 86%/0.99 inferred from LSU and ITS sequences,respectively.Karl.digitatum was first reported as Karenia digitata,a new harmful algal species bloomed in Hong Kong,China,in 1998.In present study,we gave a detailed morphological and phylogenetic description of Karl.digitatum and submitted the molecular sequences of this species to GenBank for the first time.
基金financially supported by Foundation of Fujian Educational Committee(JA14348)
文摘A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I 】 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.
基金Supported by the Public Welfare Project Foundation of Henan Province,No.20130010
文摘AIM To explore the anti-tumor effects of esophageal cancerrelated gene 2(ECRG2) in combination with cisplatin(DDP) in DDP-resistant esophageal cancer cells(EC9706/DDP).METHODS A drug-resistant cell model was established, with EC9706/DDP cells being treated with ECRG2 and/or DDP. Cell viability was examined by MTT assay. The rate of cell apoptosis was determined by flow cytometry. The mR NA expression levels of proliferating cell nuclear antigen(PCNA), metallothionein(MT), and p53 were determined by RT-PCR and PCNA, while MT and p53 protein expression levels were determined by western blotting.RESULTS The anti-proliferative effect of ECRG2 in combination with DDP was superior when compared to ECRG2 or DDP alone. The inhibition rate for the combination reached its peak(51.33%) at 96 h. The early apoptotic rates of the control, ECRG2 alone, DDP alone, and ECRG2 plus DDP groups were 5.71% ± 0.27%, 12.68% ± 0.61%, 14.15% ± 0.87%, and 27.96% ±0.36%, respectively. Although all treatment groups were significantly different from the control group(P < 0.05), the combination treatment of ECRG2 plus DDP performed significantly better when compared to either ECRG2 or DDP alone(P < 0.05). The combination of ECRG2 and DDP significantly upregulated p53 m RNA and protein levels and downregulated PCNA m RNA and protein levels compared to ECRG2 or DDP alone(P < 0.05). However, no changes were seen in the expression of MT mR NA or protein.CONCLUSION ECRG2 in combination with DDP can inhibit viability and induce apoptosis in esophageal cancer DDP-resistant cells, possibly via upregulation of p53 expression and downregulation of PCNA expression. These findings suggest that the combination of ECRG2 and DDP may be a promising strategy for the clinical treatment of esophageal cancers that are resistant to DDP.
基金Supported by the Youth Backbone Training Plan of the Beijing Academy of Science and Technology(No.201602)the National Nature Science Foundation of China(No.41606175,41576162)+1 种基金the National Key R&D Program of China(No.2017YFC1404301)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA1102030401)
文摘The dinoflagellate genus K arenia is known for recurrent harmful blooms worldwide. However, species diversity of the genus is generally overlooked owing to the difficulty of identifying small unarmored dinoflagellates. We have established four clonal cultures of K arenia longicanalis isolated from the type locality, Hong Kong harbor(strain HK01) and other three locations along the Chinese coasts(strains YB01, DT01, and NJ01). The morphology of the strain was studied by light and scanning electron microscopy(LM and SEM) and the pigment composition analyzed by high-performance liquid chromatography. We provide the first molecular data of K. longicanalis based on the large subunit(LSU) rRNA gene sequence and internal transcribed spacer(ITS). The four strains showed identical LSU rDNA sequences with a similarity of 99.4% to the holotype of K arenia umbella(strain KUTN05) from Australia. In the ITS phylogeny, the sequence of K. umbella branched between the Chinese strains of K. longicanalis. A careful comparison of the morphology of K. longicanalis and K. umbella reveals the similarity in the diagnostic characters. Diff erences may appear due to the sample treatment for SEM. We conclude that K. umbella is a junior synonym of K. longicanalis.
基金financially supported by Foundation of Fujian Educational Committee(JA14348)the National Natural Science Foundation of China(No.21171037)
文摘A novel europium（Ⅲ） coordination polymer, [Eu3（pydc）3（SO4）（H2O）5（ox）0.5]·3H2O（1, H2ox = oxalic acid, H2 pydc = pyridine-2,6-dicarboxylic acid）, has been synthesized hydrothermally from the self-assembly of lanthanide ions（Eu3＋） with the flexible oxalic acid and the rigid pyridine-2,6-dicarboxylic acid ligands, respectively. It crystallizes in the triclinic system, space group P1 with a = 11.225（4）, b = 12.390（5）, c = 13.752（5）A, α = 89.228（7）, β = 71.142（6）, γ = 75.552（6）°, Dc = 2.317 g/cm^3, μ = 5.480 mm^-1, F（000） = 1150, Z = 2, the final R = 0.0351 and w R = 0.0949 for 8782 observed reflections with I 〉 2σ（I）. Structural analysis reveals that complex 1 exhibits a three-dimensional metal-organic framework via π-π stacking interactions. In addition, complex 1 displays a red fluorescence emission in the solid state at room temperature, which corresponds to the 5D0 → 7F2 transition of Eu3＋ ions.
文摘This study investigated the effects of miRNA-155 on malignant biological characteristics of NK/T-cell lymphoma cell lines and the possible mechanism. The expression of miRNA-155 was detected in lymphoma cell lines from different sources （SNK-6, YTS, Jurkat and DOHH2） by real-time PCR. Lentiviral vectors （pLL3.7） that could overexpress or downexpress miRNA-155 were constructed. Recombinant lentiviral particles were prepared and purified, and their titers determined. The expression of miRNA-155 in the infected SNK-6 cells and the cell proliferation were detected by PCR and CCK-8, respectively. Flow cytometry was used to determine the apoptosis of infected SNK-6 cells. The target of miRNA155 was predicted from Targetscan website. The effect of miRNA155 on FOXO3a expression was examined by Western blotting. The results showed that among the human NK/T-cell lymphoma cell lines SNK-6, YTS, Jurkat and DOHH2, the expression of miRNA-155 was highest in SNK-6. The infection efficiency of the recombinant lentivirns in SNK-6 was more than 70% at multiplicity of infection （MOI） of 100. The expression of miRNA-155 was significantly increased in SNK-6 cells infected by lentivirus vectors with high expression of miRNA-155 （4 times higher than the control group）, and profoundly decreased in those infected with lentivirnses with low expression of miRNA-155. The proliferation of letivirns-infected SNK-6 cells was decreased as the expression of miRNA-155 reduced. The apoptosis rate was increased with the reduction in the expression of miRNA-155. FOXO3a was found to be a possible target of miRNA155, as suggested by Targetscan website. Western blotting showed that the expression of FOXO3a was significantly elevated in SNK-6 cells with miRNA-155 inhibition. It was concluded that reduction in miRNA-155 expression can inhibit the proliferation of SNK-6 lymphoma cells and promote their apoptosis, which may be associated with regulation of FOXO3a gene.
基金Supported by the National Key Research and Development Program of China(Nos.2017YFC1404404,2017YFC1404402)the National Natural Science Foundation of China(No.41906112)the Scientific and Technological Innovation Project of the Qingdao National Laboratory for Marine Science and Technology(No.2016ASKJ02)。
文摘Over the past decades,jellyfish occurred increasingly and abundantly in coastal areas worldwide.Usually,biomass of jellyfish,especially when they bloom,can be determined by visual counting.However,tiny individuals of jellyfish(e.g.,planulae,polyps,and ephyrae)are difficult to detect in the field.In this study,species-specific quantitative real-time PCR assays(qPCR)(SYBR Green I)targeting the mitochondrial 16S rDNA(mt-16S rDNA)of jellyfish were developed and were used to estimate the distribution and seasonal fluctuations of four jellyfish species(Nemopilema nomurai,Cyanea nozakii,Rhopilema esculentum,and Aurelia coerulea)in Jiaozhou Bay(JZB),China in 2013.The mt-16S rDNA of A.coerulea and N.nomurai was detected in most of the survey months and it peaked in July(1.03×10^(4) copies/L)and September(1.08×10^(6) copies/L),respectively.The mt-16S rDNA of C.nozakii occurred from August to October only with monthly mean values of 7.18-46.17 copies/L and was mainly located from the middle part to the outer part of the bay.The mt-16S rDNA of R.esculentum was the least abundant among the four species and was detected in only one sample(B2 station in March),with a value of 88.49 copies/L.The Spearman correlation test revealed that phytoplankton biomass was significantly and positively correlated with the mt-16S rDNA abundance of A.coerulea(R=0.37,P<0.01)and negatively with the mt-16S rDNA of N.nomurai(R=-0.36,P<0.01).The qPCR assay will enable the identification and quantification of jellyfish species in their whole life history and can be used as an approach in combination of the traditional jellyfish survey.
基金the traditional Chinese medicine(TCM)clinical research base contribution subject of the State Administration of TCM of China(JDZX2012039)special scientific research of Chinese Medicine Industry of the State Administration of TCM of China(201207001)
文摘Objective To identify significant factors related to the apolipoprotein B/apolipoprotein A1 （apoB/A1） ratio and investigate the association between the apoB/A1 ratio and metabolic syndrome （MS） in polycystic ovary syndrome （PCOS） women. Methods Totally 307 subjects with PCOS were collected and recruited fulfilling the revised 2003 Rotterdam diagnostic criteria. MS was diagnosed by the National Cholesterol Education Program-Adult treatment Panel （NCEP-ATP） III criteria. Results The prevalence of MS in PCOS women was 31.6%, whose average age was 26.2 ___＋ 5.2 years. The apoB/A1 ratio was significantly correlated with age, body mass index （BM1）, waist circumference （WC）, hip circumference, waist-to-hip ratio, blood pressure, metabolic abnormalities, sex hormone binding globulin （SHBG）, and free androgen index. In addition, SHBG had a significant association with all five component risk of MS. The increasing apoB/A1 ratio was associated with the prevalence of MS and was one of the risk factors of MS. Conclusion SHBG was considered as an additional potential factor in predicting the metabolic abnormity in PCOS women. The apoB/A1 ratio is associated with SHBG and might be an indicator of MS in PCOS women.
基金Project supported by the National Natural Science Foundation of China(61465006,61265007)
文摘Effect of divalent dopants, Zn2＋ ion, on the high-order photon avalanche （PA） upconversion （UC） emission of Er3＋ doped BiOCl microcrystals was investigated. XRD results indicated that Zn2＋ ion dopants would mostly enter into the lattice space at low and moderate doping concentration, and began to substitute Bi3＋ ion gradually at heavily doping level. Under exaction at 980 nm, the PA UC of violet, green and red emission of Er3＋ ions could be observed, and the UC emission intensity increased with increasing the Zn2＋ addition below 8 mol.%, then decreased with further addition. Power dependence study showed that the dopant concentration of Zn2＋ had no obviously negative effect on the occurrence of PA emission. On the bases of results investigated herein, we considered that the lattice distortion by Zn2＋ doping could not directly change the special PA emission of BiOCI：Er3＋, but would improve the emission intensity when used as lattice modifier.
基金Project supported by the National Natural Science Foundation of China(61465006,61265007)Reserve talents Project of Yunnan Province(2015HB013)
文摘The exploration of novel long lasting red phosphors is still of importance due to expected commercial applications and scientific interests. In this work, we reported the red long lasting phosphorescence（LLP） from Eu^3＋ doped BiOCl semiconductor polycrystals. The LLP property of the red phosphor is relatively weak due to less trap density, but the excitation band of LLP stems from the energy gap transition of semiconductor, offering experimental evidence for energy transfer between BiOCl semiconductor and Eu^3＋ ions. Although the afterglow duration of Eu^3＋ doped BiOCl was short temporarily, this work may open a novel kind of red LLP phosphors.
基金supported by National Natural Science Foundation of China Grant 81560350
文摘The purpose of this study was to compare the functional outcomes, psychological impact, and complication rates associated with external fixation and volar or dorsal plating in relation to the functional parameters following treatment of intra-articular fractures of the distal radius （IFDR） in patients older than 65 years. We hypothesized that using volar or dorsal plating would improve functional outcomes, but that it would be associated with more complications and equivalent functional outcomes when compared with the external fixation group. A total of 123 consecutive patients suffering from IFDR were recruited into the study. The patients were measured for clinical, radiological, and psychosocial functioning outcomes and were followed up after I week and 3, 6 and 12 months. After 3 months, the plating group had better pronation （P = 0.001）, supination, （P = 0.047） and extension （P = 0.043） scores. These differences were somewhat attenuated by 6 months and disappeared at I year. The plating group had a greater occurrence of wound infection （P = 0.043）, tendonitis, （P = 0.024） and additional surgery compared with the external fixation group. The only TNO-AZL Adult Quality of Life scores in the plating group that were lower than those in the external fixation group were in the ＂gross motor＂ category （walking upstairs, bending over, walking 500 yards; P = 0.023）. Internal fixation was more advantageous than external fixation in the early rehabilitation period; after I year the outcomes were similar. The plating group showed significantly higher levels of wound infection and tendonitis and had a greater need for additional surgeries.
基金Supported by the National Key R&D Program of China(No.2017YFC1404301)the National Natural Science Foundation of China(Nos.41906112,41606175)+1 种基金the Science&Technology Basic Resources Investigation Program of China(No.2018FY100200)the Beijing Natural Science Foundation(No.8194059)。
文摘Abstract On May 24–29,2019,a harmful algal bloom occurred in Pingtan coastal areas,Fujian,southeast China,and caused mass mortality of cage-cultured fi sh.Two clonal cultures of an unknown naked dinofl agellate were set up from seawater samples taken during the bloom.The cultures were examined for morphological features,ultrastructure characters,photosynthetic pigments,the large subunit(LSU)of the rRNA gene,and the internal transcribed spacer(ITS)sequences,as well as acute toxicity analysis.The cell was unarmored,small-sized,and ovoid,and was characterized by elaborate striations on the epicone and hypocone.The nucleus was large,ellipsoid to oval or kidney-shaped,and centrally located in the cell.A long linear apical groove originated above the sulcus in the ventral epicone and extended to the dorsal side.An elongate,slit-like“ventral pore”was located on the left of the epicone,well away from the apical groove.The chloroplasts were yellowish brown,numerous,band like,and irregularly distributed in the cell periphery.Fucoxanthin was the main accessory pigment composition.Phylogeny topology reconstructed on partial LSU rDNA showed that the unknown dinofl agellate branched as a sister species to Karlodinium sp.(strain IFR981&IFR797,from France)and Karlodinium corrugatum(strain KDGSO08,from Australia),with genetic divergences of 0.6%and 3.3%,respectively.Based on the morphological and molecular phylogenetic analysis,we describe the novel dinofl agellate as Karlodinium elegans sp.nov.A toxicity assay revealed that the clonal culture of K.elegans(strain PTB601)had no adverse eff ect on brine shrimp(Artemia salina)and marine medaka(Oryzias melastigma),indicating it may not be a toxic species.
文摘A new epidemic SIRS model with discrete delay on scale-free network is presented. We give the formula of the basic reproductive number for the model and prove that the disease dies out when the basic reproductive number is less than unity, while the disease is uniformly persistent when the basic reproductive number is more than unity. Numerical simulations are given to demonstrate the main results.
文摘Unemployment is one of the major vices in our contemporal society, which weigh greatly on the economy of such nation. It is also, a fact that knowing ones enemy before battle gives 50 per cent chance of victory;thus, this research aimed at providing understanding about dynamics of unemployment with consideration for retirement and possible control criterion. And the objectives are;formulation of mathematical model using the concept of deterministic model and mathematical epidemiology;then, model analysis. The model analysis includes, a numerical semi-analytical scheme for investigating validity of analytical solutions. The result of the analysis were that: 1) the model was mathematically well-pose and biologically meaningful 2) two equilibria points exist, and 3) a threshold for recruitment from the pool of unemployment, assuring victory in the fight against unemployment was also, obtained. The threshold is required to be well managed in order to win the battle against the socio-vice (unemployment) in the contemporary society. In addition, variational iterative method (VIM) is the numerical semi-analytic scheme employed to solve the model;thus, the approximate solution gave a practical meaningful interpretation supporting the analytical results and proof of verdict of assumptions of the model. The article concluded with three points;everyone has roles to play to curtail the socio-menace, beseech government and policy makers to look kindly, and create policy(ies) to sustain population growth, and the retiree should also, plan live after service, because over dependence on pension scheme could be died before death because of corruption in the scheme.
基金financially supported by the Foundation of Fujian Educational Committee(JA14348)
文摘A novel Dy^（3＋） coordination compound,（H_2pipz）（H_3O）[Dy（pydc）_3]·11H_2O（1,pipz = piperazine and H_2pydc = pyridine-2,6-dicarboxylic acid）,has been hydrothermally synthesized and characterized by X-ray single-crystal diffraction,elemental analysis. It is interesting that the packing structure of compound 1 contains 22-core water clusters. Compound 1 is extended into a threedimensional supramolecular structure via O···H···O hydrogen bonding interactions. Furthermore,the luminescent property of compound 1 was also investigated.
基金Funded by the National Natural Science Foundation of China(No.51001117)
文摘Two kinds of 2.5D deep straight-joint structure ultra-high molecular weight polyethylene（UHMWPE）（twisted and original） fibers woven fabric reinforced epoxy resin composites were prepared by the hand lay-up method. Subsequently, the flexural property, microstructures, and failure mechanisms of the composites were also investigated. The average flexural strength of 2.5D deep bend-joint structure twisted fiber and original fiber woven fabric composites were 176.66 MPa and 204.45 MPa, respectively. The results of the characteristics indicated that the twist was the main factor which affected the flexural performance. Flexural property vitally relied on the strength of the fiber itself. Twist decreased the strength of the yarns, which meant that when the mechanical property of woven fabric reinforced composites was improved, the yarns must be kept straight in the woven fabric. The study are extremely valuable to guide the improvement of the mechanical property of the woven fabric reinforced composites.
文摘Previous Background: Hemodynamic factors, like blood pressure, have been established to be major determinants of cardiac left ventricular structure. However, several factors other than blood pressure to influence cardiac mass have been implicated. When we did medical survey, cardiac left ventricular mass index (LVMI) of one ethnic group that had higher blood pressure was found to be smaller than that of the other ethnic groups with a lower blood pressure. Such contradicted data from the present study were analyzed combining blood pressure, LVMI and chemical parameters obtained from blood and urine. Methods: In a medical survey conducted in Xinjiang, China, 279 people (65 - 70 years old) from three ethnic groups (Kazakh, Uygur and Han) from two separated regions provided blood and urine samples and underwent echocardiography and 24-h ambulatory blood pressure monitoring (ABPM). Results: Systolic and diastolic blood pressure obtained from ABPM and urinary sodium excretion values were significantly higher in Kazakh than that in Uygur and Han. However, LVMI in Kazakh was lower than that in other 2 groups. Plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were significantly lowest in Kazakh. The values of LVMI in all ethnic groups were positively related to both blood pressure and PAC. An inverse correlation was identified between PAC and urinary sodium excretion value. Conclusion: Although higher blood pressure in Kazakh subjects, their LVMI was lower than those of Uygur and Han, whose blood pressure was lower than that in Kazakh. These results suggest that blood pressure is not always a determinant for LVMI value. There is a possibility that relatively lower PAC resulted from higher sodium intake suppressed the rise in LVMI caused by higher blood pressure in Kazakh.
