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Impatiens shimianensis Q. Luo (Balsaminaceae), a new species from Shimian county in southwestern Sichuan province, China, is reported and its morphological characteristics are described and illustrated. Pollen grain morphology and seeds under SEM are also described. The new species is somewhat similar to I. bahanensis, I. brachycentra, I. laxiflora, I. parviflora and I. racemosa, but differs mainly by having leaf blades with white short stiff adpressed hairs; basal lobes of lateral united petals triangular, distal lobes lanceolate; and lower sepal salver-shaped. The distinguishing characters for these six Impatiens species are given in a table. [ABSTRACT FROM AUTHOR]

Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-AlO-SiO and CaO-MgO-SiO systems, and their bending strengths up to 53.47 MPa and 99.84 MPa, respectively, were obtained. The presence of anorthite, α-quartz, magnetite, and pyroxene crystals (augite and diopside) in the steel slag ceramics were very different from the composition of traditional ceramics. X-ray diffraction (XRD) and electron probe X-ray microanalysis (EPMA) results illustrated that the addition of steel slag reduced the temperature of extensive liquid generation and further decreased the firing temperature. The considerable contents of glass-modifying oxide liquids with rather low viscosities at high temperature in the steel slag ceramic adobes promoted element diffusion and crystallization. The results of this study demonstrated a new approach for extensive and effective recycling of steel slag. [ABSTRACT FROM AUTHOR]

Polygonatum gongshanense L.H. Zhao & X.J. He (Asparagaceae), a new species from Gongshan, Yunnan Province, China, is described and illustrated. It is morphologically similar to P. cathcartii in having fleshy roots, an irregularly moniliform rhizome, opposite leaves and a pale-yellow perianth, but it differs by its pink stem, larger flowers, a retrorse spur on each of the staminal filaments, and a different ovary and fruit morphology. [ABSTRACT FROM AUTHOR]

Chromosome numbers and karyotype data of 19 Chinese Polygonatum species generated from 51 populations are presented in this paper. Karyograms of P. cirrhifoliodes, P. gracile, P. hookeri, P. jinzhaiense and P. nodosum are reported for the first time. The chromosome numbers 2n. 28 for P. hookeri and 2n. 60 for P. zanlanscianense are reported for the first time. Satellite chromosomes in the analyzed Polygonatum species can be classified into nine types with respect to the position of secondary constrictions. The occurrence of these types correlates with the infrageneric classification. Karyotypes are bimodal in most Polygonatum species. Polyploidy is common in Polygonatum, and polyploid taxa exhibit higher karyotype asymmetry. [ABSTRACT FROM AUTHOR]

With rapid development of high educationm, the construction of experiment technician team is gradually put on schedule. But, as we know, the construction of experiment technician team is a systematic engineering, it needs planning and layout overall. This article through deeply analyzing construction of management system of experimental technical team, from talent introduction, post appointment, skiils training and performance appraisal, introduce methods of experimental technical team construction, tries to find out advantages and disadvantages of our experimental technical team in construction and management. Thus, we can put forward construction threads and methods to strengthen experimental technical team. [ABSTRACT FROM AUTHOR]

In recent years, virtual laboratory technology has won our high favor in areas of teaching and research owning to its advantages, such as good interactivity and undemanding requirements for hardware. This article discusses the mixed programming of Matlab and LabVIEW. Then, two kinds of technology--SIT software package and DLL are mainly studied. On this basis, a detailed account of the methods of building a virtual electronic power laboratory and respective technical advantages are given, by taking a single-phase half-wave circuit experiment as an example. By contrast, SIT can make the calling process of Matlab in LabVIEW and its implementation simple and easy, but it can not be separated from the Matlab environment. The realization process of DLL technology is more complex, but it can be completely detached from the Matlab environment. Both methods can successfully achieve software simulation and web publishing of virtual laboratory. [ABSTRACT FROM AUTHOR]

In the 20CrMnTi steel production process, the nitrogen content increased by 19 × 10 and 29 × 10, respectively, during ladle furnace (LF) refining and during the casting process from ladle to tundish. The protective casting is the key to decrease the N content. The results of thermodynamic calculations and a growth kinetics investigation show that TiN formation occurs only when the solidification fraction is greater than 0.533 under the controlled conditions used in this study for the manufacture of 20CrMnTi steel; the radius of TiN particles decreases as the Ti and N contents decrease and as the cooling rate increases. Furthermore, the theory of austenite grains controlled by second-phase particles was analyzed. The elemental analysis results showed that the Ti content was controlled at 0.04wt%-0.06wt% and the N content decreased to 0.005wt%, which satisfy the requirements for grain refinement but can also effectively prevent the precipitation of TiN inclusions in 20CrMnTi steel. [ABSTRACT FROM AUTHOR]

To obtain advanced quality pure copper, the microstructure of solidified copper was optimized by imposing electric pulse on liquid copper in this study. Experiments were performed to determine the effect of electric pulse voltage, arrangement mode of electrodes, and energy input on the microstructure of solidified copper. The results show that, when the energy input of electric pulse is bigger than 28.95 kJ per ton copper, the percent of fine grains increases noticeably with the increase of energy input; but when the energy input of electric pulse is smaller than 28.95 kJ per ton copper, the percent of fine grains decreases with the increase of energy input. The influence order of above factors on grain refinement is electric pulse voltage > arrangement mode of electrodes > energy input. According to the above experimental results, the optimum process conditions are chosen as the voltage being 400 V and the energy input greater than 28.95 kJ per ton copper. Meanwhile, the best arrangement mode of electrodes should be that, one electrode is immerged in the middle of liquid copper in the crystallizer, and the other is connected to the inner wall of the crystallizer, which is divided into two electrode poles for the symmetrical electric field distribution. [ABSTRACT FROM AUTHOR]

Using steel slag as a main raw material of ceramics is considered as a high value-added way. However, the relationship among the initial composition, ceramic microstructure, and macroscopic properties requires further study. In this paper, a series of ceramics with different slag ratios (0-70wt%) were designed, and the software FACTsage was introduced to simulate the formation of crystalline phases. The simulation results indicate that mullite is generated but drastically reduced at the slag ratios of 0-25wt%, and anorthite is the dominant crystalline phase in the slag content of 25wt%-45wt%. When the slag ratio is above 45wt%, pyroxene is generated more than anorthite. This is because increasing magnesium can promote the formation of pyroxene. Then, the formula with a slag content of 40wt% was selected and optimized. X-ray diffraction results were good consistent with the simulation results. Finally, the water absorption and bending strength of optimized samples were measured. [ABSTRACT FROM AUTHOR]

Objectives: Clinically, it is very difficult to prevent pathological fracture caused by high recurrence rate of osteolytic disease of proximal femur in children. At present, there is no consensus in clinical studies of which internal fixation method can significantly reduce the probability of recurrence of pathological fracture. The study aims to research the mechanical properties of different internal fixations in the treatment of osteolytic lesions of proximal femur in children by finite element analysis, and to find out the optimal treatment. Methods: Based on finite element analysis, the osteolytic disease models of the femoral neck and intertrochanter in a child (8‐year‐old, boy) were established respectively, and different internal fixation models (plate and titanium elastic intramedullary nails, TENs) were assembled. For the osteolytic lesion of the femoral neck: model A1 was assembled with a plate; model A2 with two TENs crossing the physis; model A3 with two TENs without crossing the physis. And for pertrochanteric osteolytic lesion: model B1 was assembled with a plate, model B2 with two TENs crossing the physis and model B3 with two TENs without crossing the physis. The Eccentric bearing load, torsional restraintal restraint of calcar femorale and composite load were analyzed for each models. Results: When the yield strain of each model is reached, the stress concentration points are located in the proximal and distal femoral calcar. In the model of femoral neck lesions, the failure load of model A1 and model A2 are the same (1250 N), and the failure load of model A3 (980 N) is significantly lower than that of the former two; in the model of intertrochanteric lesions, the failure load of model B2 is the largest (1350 N), and the failure load of model B1 (1220 N) is lower than that of model B3 (1260 N), but both are smaller than that of model B2. Conclusion: Through finite element analysis, TENs through the epiphyseal plate, is found to be the better internal fixation method for femoral neck lesions and intertrochanteric lesions under two different working conditions. The results of clinical correlation study provide new biomechanical information for orthopedic doctors to consider different treatment options for osteolytic lesions of proximal femur. [ABSTRACT FROM AUTHOR]

Abstract: Semiconductor quantum dots (QDs) as a kind of biological labeling material have many unique fluorescence properties relative to conventional organic dyes, which can be used for long-term fluorescence tracking. In this work, a facile method was developed for synthesizing water-stable ZnO nanoparticles with green emission. The as-synthesized ZnO nanoparticles were shown to be highly stable and soluble in water. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) as well as UV–vis and fluorescence spectrophotometry (PL) were employed to investigate the structures and properties of ZnO nanoparticles. Furthermore, hemolysis assay was performed to evaluate the biocompatibility of these ZnO nanoparticles in vitro. The results indicate that the as-prepared ZnO nanoparticles have biocompatibility, which make them a promising cell label. [Copyright &y& Elsevier]

A high Nb containing TiAl alloy was prepared from the pre-alloyed powder of Ti-45Al-8.5Nb-0.2B-0.2W-0.02Y (at%) by spark plasma sintering (SPS). Its high-temperature mechanical properties and compressive deformation behavior were investigated in a temperature range of 700 to 1050°C and a strain rate range of 0.002 to 0.2 s. The results show that the high-temperature mechanical properties of the high Nb containing TiAl alloy are sensitive to deformation temperature and strain rate, and the sensitivity to strain rate tends to rise with the deformation temperature increasing. The hot workability of the alloy is good at temperatures higher than 900°C, while fracture occurs at lower temperatures. The flow curves of the samples compressed at or above 900°C exhibit obvious flow softening after the peak stress. Under the deformation condition of 900-1050°C and 0.002-0.2 s, the interrelations of peak flow stress, strain rate, and deformation temperature follow the Arrhenius' equation modified by a hyperbolic sine function with a stress exponent of 5.99 and an apparent activation energy of 441.2 kJ·mol. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduced a novel synchronous buck converter with soft-swithcing (ZCS and ZVS) for battery charger. The converter structure is simple and easy control.New converter combines synchronous retification and soft-swithing (ZCS and ZVS) to decrease circuit losses. Moreover, the circuit is designed to make current never pass through body diode of synchronous rectifier. Thus,the circuit avoids diode recovery effects which happened frequently in sycnchronous converter topologies. The operating modes of the converter and equivalent circuits are identified by analyzing the operating principles of the charger circuit. Simulation results reveal the theoretical effectiveness of novel battery charger with little voltage ripple and circuit losses, fast dynamic reponse and high efficiency. [Copyright &y& Elsevier]

Original series pattern, 1-AGO sequence's smooth degree and its initial value are main factors affecting the prediction accuracy of GM (1,1) model. To enhance the prediction accuracy, according to the investigation of original method on improving smooth degree of series, a new grey improved algorithm based on weighted and minimum average relative error is put forward. Comparative results with original method show that this new algorithm is more accurate and useful for other general series. The traditional and improved algorithms are applied to practical machine fault diagnosis and life prediction. According to the experimental results, it can be concluded that the new grey improved algorithm can offer very valuable information for preventative maintenance of machinery equipment. [ABSTRACT FROM AUTHOR]

The 3D metal-organic framework based on cadmium complex of pyrazine-2,3,5,6-tetracarboxylate (pztc), {Cd(pztc)(HO)}, has been synthesized by the reaction of Hpztc and Cd(NO)·4HO under hydrothermal conditions and characterized by elemental analysis, IR, single-crystal X-ray diffraction and fluorescence measurement. This complex belongs to triclinic system, $$ P\overline{1} $$ space group with a = 5.0080(10) Å, b = 6.6578(13) Å, c = 8.5790(17) Å, α = 89.28(3)°, β = 75.76(3)°, γ = 78.80(3)°. All the donor N and O atoms in pztc coordinate to Cd(II) ions. As decadentate ligand, each pztc links eight Cd(II) atoms, which is a novel coordination mode of pztc. Graphical Abstract: The 3D metal-organic framework based on cadmium complex of pyrazine-2,3,5,6-tetracarboxylate (pztc), {Cd(pztc)(HO)}, has been synthesized by the reaction of Hpztc and Cd(NO)·4HO under hydrothermal conditions. All the donor N and O atoms in pztc coordinate to Cd(II) ions. As decadentate ligand, each pztc links eight Cd(II) atoms, which is a novel coordination mode of pztc.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Background. Breast carcinoma is one of most prevalent malignant tumors occurring in women. Short of prevention, detection of breast carcinoma at an early, still curable stage would offer the best route to decrease its mortality rates. This highlights the urgent need for suitable biomarkers for early diagnosis and a better understanding of the disease pathogenesis. Material and methods. NMPs were extracted from normal human breast tissue (Group I), from hyperplastic mammary tissue specimens (Group II), from atypical epithelial hyperplasia specimens (Group III), and from breast carcinoma (Group IV) tissue. Differential proteome profiles were established and analyzed by means of immobilized pH gradient-based two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The different NMPs were analyzed in the National Center for Biotechnology Information (NCBI) database with Mascot software. Results. Well-resolved, reproducible 2-DE profiles of human breast tissues were obtained. Average protein spots were 904 ± 58, 912 ± 51, 931 ± 63, 944 ± 70 in Group I, Group II, Group III, and Group IV, respectively. Several different proteins were analyzed using mass spectrometry and bioinformation. Of these, 12 were well characterized. Compared to Group I, three proteins were up-regulated in Groups II, III, and IV, including Hsp27, prohibitin, and laminA/C. Upregulation was confirmed using Western blotting and immunohistochemical analysis. The correlation of prohibitin expression with clinicopathological features was also investigated. Discussion. The proteins identified in this study may potentially prove to be useful markers for breast carcinoma diagnosis. [ABSTRACT FROM AUTHOR]

An antifungal protein was isolated from a culture of Bacillus subtilis strain B29. The isolation procedure comprised ion exchange chromatography on diethylaminoethyl (DEAE)-52 cellulose and gel filtration chromatography on Bio-Gel® P-100. The protein was absorbed on DEAE-cellulose and Bio-Gel® P-100. The purified antifungal fraction was designated as B29I, with a molecular mass of 42.3 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), pI value 5.69 by isoelectric focusing (IEF)-PAGE, and 97.81% purity by high performance liquid chromatography (HPLC). B29I exhibited inhibitory activity on mycelial growth in Fusarium oxysporum, Rhizoctonia solani, Fusarium moniliforme, and Sclerotinia sclerotiorum. The 50% inhibitory concentrations (IC50) of its antifungal activity toward Fusarium oxysporum and Rhizoctonia solani were 45 and 112 μmol/L, respectively. B29I also demonstrated an inhibitory effect on conidial spore germination of Fusarium oxysporum and suppression of germ-tube elongation, and induced distortion, tumescence, and rupture of a portion of the germinated spores. [ABSTRACT FROM AUTHOR]

Thermally conductive polymer composites (TCPCs) are highly desirable for thermal management in electronic devices and modern electrical systems. However, it still remains a great challenge to reconciliate the conflict between thermal conductivity and mechanical properties of TCPCs. Herein, we realized the development of multilayer gradient boron nitride nanosheet/aramid nanofiber (BNNS/ANF) films with excellent thermal conductivity and improved tensile strength. The multilayer gradient BNNS/ANF films achieved a superior in-plane thermal conductivity of 19.13 W/(m K) and a high tensile strength of 59.3 MPa, with 23.6% and 61.6% increases compared to the single-layer BNNS/ANF film at the same BNNS content. Finite element analysis was used to clarify the enhanced mechanism of the multilayer gradient structure on thermal conductivity and tensile strength. These desirable properties demonstrate that the multilayer gradient structure is an efficient strategy to address the conflict between thermal conductivity and mechanical properties, and paves the way for the design and preparation of high-performance TCPCs for thermal management applications. [ABSTRACT FROM AUTHOR]

The inner cell mass of the pre-implantation blastocyst consists of the epiblast and hypoblast from which embryonic stem cells (ESCs) and extra-embryonic endoderm (XEN) stem cells, respectively, can be derived. Importantly, each stem cell type retains the defining properties and lineage restriction of its in vivo tissue origin. We have developed a novel approach for deriving porcine XEN (pXEN) cells via culturing the blastocysts with a chemical cocktail culture system. The pXEN cells were positive for XEN markers, including Gata4, Gata6, Sox17, and Sall4, but not for pluripotent markers Oct4, Sox2, and Nanog. The pXEN cells also retained the ability to undergo visceral endoderm (VE) and parietal endoderm (PE) differentiation in vitro. The maintenance of pXEN required FGF/MEK+TGFβ signaling pathways. The pXEN cells showed a stable phenotype through more than 50 passages in culture and could be established repeatedly from blastocysts or converted from the naïve-like ESCs established in our lab. These cells provide a new tool for exploring the pathways of porcine embryo development and differentiation and providing further reference to the establishment of porcine ESCs with potency of germline chimerism and gamete development. [ABSTRACT FROM AUTHOR]

Phototherapy may have an adverse effect on the hemodynamics of preterm infants, and endothelin (ET) and nitric oxide (NO) are both the powerful vasoactive substances. This study was designed to observe the effect of phototherapy on blood levels of ET and NO in preterm infants. Sixty-four preterm infants with hyperbilirubinemia requiring phototherapy were studied. Among them, 31 patients were born at 32–36 weeks’ gestational age (GA), and 33 patients were ≤32 weeks GA. Control group included 26 full-term infants with hyperbilirubinemia requiring phototherapy. All patients were treated with continuous phototherapy for 24 hours. Blood samples were collected before and after phototherapy. The amount of ET in the blood samples was determined by radioimmunoassay, and NO levels were determined using nitrate reductase. Heart rate, respiratory rate, apnea, and mean arterial blood pressure (MABP) were monitored regularly (defined interval: hourly, 4 hours, etc) during phototherapy. Blood ET levels measured after 24 hours of phototherapy were higher than the pretreatment values, as were blood NO levels measured after 12 hours and 24 hours of phototherapy. Both increases were statistically significant ( P<0.05) in the GA≤32 weeks group. In the GA>32 weeks group, blood NO levels measured after 24 hours of phototherapy were higher than the pretreatment values; these changes were also statistically significant ( P<0.05). In the GA≤32 weeks group, heart rate increased and the MABP decreased during phototherapy. The changes after 24 hours of phototherapy compared to the pretreatment values were statistically significant. A few episodes of apnea occurred during phototherapy in the GA≤32 weeks group. This was significantly higher than that in the other two groups. Under phototherapy, blood levels of ET and NO were significantly higher in preterm infants, especially in preterm infants of ≤32 weeks GA. [ABSTRACT FROM AUTHOR]

The development of highly thermally conductive composites with excellent electrical insulation has attracted extensive attention, which is of great significance to solve the increasingly severe heat concentration issue of electronic equipment. Herein, we report a new strategy to prepare boron nitride nanosheets (BNNSs) via an ion-assisted liquid-phase exfoliation method. Then, silver nanoparticle (AgNP) modified BNNS (BNNS@Ag) was obtained by in situ reduction properties. The exfoliation yield of BNNS was approximately 50% via the ion-assisted liquid-phase exfoliation method. Subsequently, aramid nanofiber (ANF)/BNNS@Ag composites were prepared by vacuum filtration. Owing to the "brick-and-mortar" structure formed inside the composite and the adhesion of AgNP, the interfacial thermal resistance was effectively reduced. Therefore, the in-plane thermal conductivity of ANF/BNNS@Ag composites was as high as 11.51 W m−1 K−1, which was 233.27% higher than that of pure ANF (3.45 W m−1 K−1). The addition of BNNS@Ag maintained tensile properties (tensile strength of 129.14 MPa). Moreover, the ANF/BNNS@Ag films also had good dielectric properties and the dielectric constant was below 2.5 (103 Hz). Hence, the ANF/BNNS@Ag composite shows excellent thermal management performance, and the electrical insulation and mechanical properties of the matrix are retained, indicating its potential application prospects in high pressure and high temperature application environments. [ABSTRACT FROM AUTHOR]