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The differentiation of embryonic stem cells (ESCs) into germ cells

Extracts from plants used in Chinese medicine can be good sources of fungicides for agricultural applications. In this study, we separated and identified antifungal compounds from four traditional Chinese medicine extracts and evaluated their antifungal activities

Extracts from plants used in Chinese medicine can be good sources of fungicides for agricultural applications. In this study, we separated and identified antifungal compounds from four traditional Chinese medicine extracts and evaluated their antifungal activities in vitro and in vivo. In vitro, honokiol extracted from Artemisia argyi showed broad-spectrum antimicrobial and mycelial inhibitory activity with EC50 in the range 3.56 − 33.85 μg/mL against eight plant pathogens. q-PCR indicated that honokiol might induce cell cancerisation and inhibit cellular respiration, which provided significant insights into honokiol function in tobacco resistance to molecular mechanisms of the phytopathogenic fungus Phytophthora nicotianae. In vivo, honokiol significantly decreased the rate of fungal infection in eggplants, potatoes, grapes, cherry tomatoes, and cucumbers, and enhanced disease resistance in tobacco. Overall, our results indicate that honokiol has the potential to control a variety of fungal and oomycete diseases, and A. argyi could be a source of honokiol.

The Eu2+/3+ mixed-valent complexes have aroused attention because of their potential application in the catalytic field endowed by the variable valence. Herein, we develop an ingenious green strate...

The South African Mutton Merino (SAMM), a dual-purpose (meat and wool) sheep breed, is characterized by its excellent performance on growth, carcass traits and meat quality compared to other fine-wool Merino breeds. Nowadays, the SAMM breed has been widely used to cross with commercial and indigenous fine-wool or coarse-wool breeds to improve the growth and meat performance in many countries. To date, however, little is known about the genetic basis for its prominent characteristics. In this study, whole-genome sequences of 10 SAMM were sequenced and the selection signatures were analyzed together with those of 39 Australian Merino and Chinese Merino (wool-type Merino) by F

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The phosphorescence lifetime approach based on the room temperature phosphorescence (RTP) property has received considerable attention in recent years due to its excellent performance in the precise measurement of oxygen. Herein, a smart nanoprobe, Gd[PC]@ZIF-8, was designed and assembled by homogenously encapsulating a rare-earth complex phosphor Gd[(Pyr)4cyclen] (Pyr = pyrenol) into a zeolitic imidazolate framework (ZIF-8). Because of the restriction of the metal-organic framework (MOF) matrix and host-guest interactions, the nanoprobe Gd[PC]@ZIF-8 exhibited highly enhanced RTP properties, including intensity, quantum yield, and elongated decay lifetime. It displayed an outstanding linear relationship between the phosphorescence decay lifetime, intensity and oxygen concentration, which can be applied in the field of oxygen sensing. Moreover, the complex Gd[(Pyr)4cyclen] in the nanoprobe Gd[PC]@ZIF-8 served as a favorable photosensitizer that resulted in the simultaneous conversion of sufficient oxygen molecules into single state oxygen (1O2) under irradiation during the phosphorescence quenching process, which is conducive to photodynamic therapy (PDT). Thus, the design of the smart nanoprobe Gd[PC]@ZIF-8 in this study provides an ingenious strategy of utilizing a MOF as a matrix to enhance the RTP properties of phosphors for synchronous oxygen sensing and PDT.

We demonstrate highly efficient organic ultraviolet photodetectors using 4,4’,4’’ -tris[3-methyl-pheny(phenyl) amino] triphenylamine (m-MTDATA) and aluminum Tris(8-Hydroxyquinolinate) Synonym Alq 3 ). The optimized photodetector delivers a photocurrent of 1.40 mA/cm 2 at10 V, corresponding to a response of 127 mA/W under an illumination of 375 nm UV light irradiation with an intensity of 10.5 mW/cm 2 and a detectivity of 2.15×10 11 cm Hz 1/2 /W. The high response is attributed to the larger band offset at m-MTDATA/ Alq 3 heterojunction, the suppression of radiative decay of m-MTDATA and efficient electron transfer from m-MTDATA to Alq3. The working mechanism of harvesting high performance is also discussed in detail.

Cellulose/Ag/polyaniline conductive composites with excellent electrical conductivity were fabricated by the ultrasonic method for the first time. The products were characterized by UV–Vis spectrometer, Fourier-transform infrared spectroscopy, Scanning electron microscopy, Thermogravimetric and Conductivity analysis, and the results showed that the Ag nanoparticles (nanoAg) with the good conductivity coated uniformly on the surface of cellulose and improved the conductivity of cellulose/Ag/polyaniline composites significantly. The conductivity value was up to 0.348 S/cm, which was higher than pure polyaniline (0.142 S/cm) and cellulose/polyaniline composites (3.0 × 10−2 S/cm). In addition, compared with cellulose/polyaniline composites, cellulose/Ag/polyaniline composites also have the enhanced thermostability. The cellulose/Ag/polyaniline conductive composites would have a promising application in a variety of fields due to its unique structure and excellent properties.

The graphite nanosheets/polyaniline (GN/PANI) nanorods composites were fabricated via ultrasonic polymerization of aniline monomer in the presence of GN, which was used as electric filling. The kind of doped acids, the concentration, and the contents of the GN were used as impact factors to the conductivity of the materials that were investigated. The structure of nanocomposites were characterized by FTIR and SEM. The results show that ultrasonic can effectively restrain the agglomerate of the aniline and come to uniformity nanorods composites. The conductivity reached to 4.8 S/cm and 22 S/cm, respectively. The thermal stability of GN/PANI nanorods composites is superior to pure PANI as shown by TG analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

A series of conductive composites cellulose–polyaniline (PANI) were heterogeneously synthesized by chemical oxidative polymerization of aniline with native cellulose activated by various acids. The chemical structure and morphology of the composites were examined by FT-IR analysis and TEM. TGA was used to study their thermal properties. The composites prepared using the di-basic acids exhibited more favorable conductivity than the composites prepared using the monobasic acids. The content of PANI increased with increasing of activation time, and while the conductivity decreased because of the aggregation of PANI particles at the activation time range from 50 to 120 min. Both the PANI content and the electrical conductivity increased with an increase of the amount of aniline, and reached the maximum values at the 0.5 g aniline, respectively. The acids were able to successfully activate cellulose and lead to the improvement of the accessibility and reactivity of the O–H groups. The composites were highly stable compared to pure cellulose due to the safeguard from PANI slices. This work provided a facile method for the synthesis of cellulose–polyaniline conductive composites with excellent conductivity.

Insulin-like growth factor-I (IGF-I) plays a fundamental role in postnatal mammalian growth, development, and metabolism. The mammalian IGF-I gene contains at least six exons from which several different mRNAs are transcribed. In this study, IGF-I mRNA in Songliao black pig liver was investigated using RLM-RACE. Using a 3'-RACE technique, we determined that all mRNA transcripts lacked exon 5 sequence and contained only exon 6 sequence. Using a 5'-RACE technique, we investigated the presence of class 1 and class 2 IGF-I mRNAs. In several other species, the class 1 and class 2 IGF-I polypeptides are generated from mRNAs containing exon 1 or exon 2, respectively. Both class 1 and class 2 IGF-I mRNAs were identified in Songliao black pig liver. Transcription is initiatated upstream of exons 1 and 2 at multiple dispersed start sites to yield two distinct IGF-I mRNA transcript classes which differ in the precursor peptides predicted from their individual leader sequences. Tissue distribution of Songliao black pig class 1 and class 2 IGF-I mRNA was investigated by real-time RT-PCR. Both classes of IGF-I mRNA were expressed in a variety of tissues, however, class 1 IGF-I mRNA was more abundant than class 2 in all tissues.

Improving the quality and extending the service life of hot-forging dies were a great system engineering. There were many Influencing factors. In order to find the very measure of extending hot-forging service life one must systematically research on the working conditions, failure features and reasons from the theory and practice, mastered the relations of die materials among component, microstructure and properties, analyzed the whole process of dies in designing, manufacturing and using.

Thermal healing experiment to inner crack made by compressing a drilled hole on samples of Q235 steel with various La addition was carried out. The effects of various heating temperature on the appearance and morphology evolution of inner crack healing in Q235 steel were investigated. Optical microscope and SEM observation indicate that artificial inner crack samples of Q235 steel with La addition can occur healing phenomenon at 650 °C, while inner crack samples have apparent healing at 800 °C and the microstructure in healing area is mainly ferrite. La in the solute solution decreases the critical healing temperature, makes the microstructure in host appear obvious variety during crack healing, not only decreases the quantity of pearlite and its shape becomes like-pearlite or granular but also increases the quantity of ferrite and the concentration of carbon in ferrite. The healing process was controlled by the diffusion and migration of Fe atoms from steel host to crack zone.

In this paper, the model of piezo-valve type electric-pneumatic valve positioner is established based on the motion equation, the ideal air equation, the energy equation, and the Newton's Second law. It takes into consideration the friction force in piston seals, the change of active volume due to the piston moving, leakage at the positioner, dynamics and flow nonlinearities through the positioner orifice, the difference between the entering process and exhausting process of each piezo-valve, and the difference between the charging process and discharging process. Experiment result provides an accurate description for dynamic process and characteristic of the positioner. The time response of regulation process can be determined based on these curves. It is very useful for control strategy investigation of positioner, in spite of that the control strategy is Pulse Width Modulation, Fuzzy Control, or Adapt Control. This approach can be applied to process control, automatic instrument, robotic, and auto.