Synthesis of YAG∶Ce^(3+) Phosphor by Polyacrylamide Gel Method and Promoting Action of α-Al_2O_3 Seed Crystal on Phase Formation

YAG： Ce^3 ＋ phosphor particles were prepared using polyacrylamide gel method. The structure evolution of powders during annealing process was followed by X-ray diffraction determination. It is found that some intermediate phases, including θ-Al2O3, YAM and YAP, are formed when calcining polyacrylamide gel, however, the pure YAG phase can be formed directly when calcining polyacrylamide gel with α-Al2O3 as seed crystal. These facts show that the existence of α- Al2O3 seed crystal can block the formation of θ-Al2O3, YAM and YAP, and accelerate its reaction with Y2O3 to form YAG phase directly at lower temperature. The emission peak of prepared YAG ： Ce^3 ＋ phosphor is wide with maximum at 550 nm and the exitation band has two peaks, the major one is around at 460 nm, which matches the blue emission of GaN LED and is suitable for the assemble of white LED. Some fluxes can enhance the photoluminescence intensity of phosphor particles, that can be attributed both to the improvement of crystallization processes of YAG and to the stabilization of trivalence cerium ion in YAG：Ce^3 ＋.

Synthesis,Characterization and Electromagnetic Studies on Nanocrystalline Nickel Zinc Ferrite by Polyacrylamide Gel

Nanocrystalline nickel zinc ferrite powders （Ni=Zn1-xFe2O4, A for x=0, B for x=0.2, C for x=0.5, D for x= 0.8 and E for x= 1） were synthesized by polyacrylamide gel method. X-ray diffraction （XRD）, transmission electron microscopy （TEM） and wave-guide were used to characterize the composition. The XRD results show that the dried gel powders are amorphous, and the characteristic peaks of the spinel Ni0.5Zn0.5Fe2O4 appear after the gel is calcined at 400℃ for 1 h. When the calcining temperatures are 600 and 800℃, the average grain sizes are identified by TEM to be 10 and 30 nm, respectively. The NixZn1-xFe2O4 powders have both dielectric loss and magnetic loss in the frequency range of 8.2-11.0GHz. With the increase of Ni^2＋ ions content, the dielectric parameters （ε′） and permeability （u′） of the NixZn1-xFe2O4 powders decrease while the dielectric loss （ε″）, magnetic loss （u″） and the reflection loss increase.

Synthesis,Characterization and Electromagnetic Studies on Nanocrystalline Co_(0.5)Zn_(0.5)Fe_2O_4 Synthesized by Polyacrylamide Gel

Nanocrystalline Co0.5Zn0.5Fe2O4 ferrite was synthesized by polyacrylamide gel method. The electromagnetic and microwave absorption properties of the ferrite were investigated. The results indicated that calcining temperature of the ferrite had a significant influence on the effective properties of the ferrite. When the calcining temperature was 500, 600 and 700℃, the average size of particles was 10, 30 and 80 nm, respectively. The dielectric loss （ε″） and magnetic loss （μ″） of the ferrite was around 0.65 and 0.29 at 8.2 GHz, respectively. Microwave absorption properties of the ferrites were simultaneously influenced due to the strong correlation between reflection loss and electromagnetic parameters of the ferrite.

Characterization of YSZ Ceramic Nanopowders Synthesized at Different Temperatures via Polyacrylamide Gel Method

Tetragonal zirconia (T-ZrO2) ceramic nanopowders stabilized with 3 mol% Y2O3 were synthesized via polyacrylamide gel method, using ZrOCl2?8H2O and Y(NO3)3?6H2O as raw materials. The effect of temperature on phase composition and morphology of YSZ nanopowders and sintering behavior of YSZ ceramics was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Vickers hardness tester. The aging-resistance of YSZ ceramics was measured by means of aging experiments. The results demonstrated that the phase composition of YSZ ceramic nanopowders had no obvious change and it was composed of T-ZrO2. Particle size of well-dispersed YSZ ceramic nanopowders increased from 17 to 35 nm with increasing calcining temperature from 600 to 800 ℃. There was noticeable negative correlation between calcining temperature and the relative density of YSZ ceramic at the same sintering temperature. The aging experiments showed that water vapor facilitated tetragonal to monoclinic phase transformation, and the sample that had smaller grain size exhibited better aging-resistance. It can be concluded that when the calcining temperature is 600 ℃ and sintering temperature is 1550 ℃, the relative density and hardness of YSZ ceramic arrive at the peak of 96.64% and 11.135 GPa respectively, and it has less microcracks and excellent aging-resistance.

Magnetic resonance imaging on complications of breast augmentation with injected hydrophilic polyacrylamide gel

The injection augmentation mammaplasty for cosmetic purpose has been popular recently in China. Two kinds of injectable material are used clinically, autologous fat and biomaterial. The fat injection for breast augmentation is in question with the major problems of progressive fat re-absorption, microcalcification, and fat liquefaction. Now, the principal alloplastic biomaterial for injection augmentation mammaplasty in China is hydrophilic polyacrylamide gel （HPAAG）. Although thousands of breasts have been augmented with HPAAG and it seems to be a good biocompatible material, some complications develop after HPAAG injection augmentation mammaplasty.The patients had to undergo surgery to remove the injected HPAAG and associated lesions. Ultrasonography or magnetic resonance imaging （MRI） should be taken preoperatively to demonstrate the distribution of injected HPAAG and associated lesions. In this report, the diagnostic value and clinical significance of MRI on the complications of HPAAG breast augmentation were discussed.

Conformer Analysis of a Biological G-Quadruplex Element in the Human c-MYC Promoter by Native Polyacrylamide Gel Electrophoresis

The G-quadruplexes undergo complex folding and conformation exchanges.G-quadruplex stability is substantially influenced by sequence,bufer and temperature.Mutational analysis together with nuclear magnetic resonance spectroscopy(NMR),X-ray crystallography and circular dichroism spectroscopy has been proved to be a powerful approach for G-quadruplex structural analysis.Herein,we used DNA sequence mutation and native polyacrylamide gel electrophoresis to investigate the topology and conformations of a G-quadruplex model molecule Pu18 found in the human c-MYC promoter.The guanines(G6,G9 or G18)which were not contributable to G-tetrad formation in c-MYC Pu18 sequence were mutated to thymine or adenine.We screened the buffer and temperature of gel electrophoresis for Pu18.Gel electrophoresis showed that two of the four conformers of c-MYC Pu18 in 100 mM K+buffer were resolved,which was in accordance with the conformations as determined by the 1 H NMR spectra in previous studies.This technique is expected as a general methodology for its easy operation and low cost to facilitate uncovering more yet unidentified G-quadruplex folds and functions,with the assistance of other analytical methods like NMR,X-ray crystallography and circular dichroism spectroscopy.

A method to determine Young's modulus of soft gels for cell adhesion

A convenient technique is reported in this note for measuring elastic modulus of extremely soft material for cellular adhesion. Specimens of bending cylinder under gravity are used to avoid contact problem between testing device and sample, and a beam model is presented for evaluating the curvatures of gel beams with large elastic deformation. A self-adaptive algorithm is also proposed to search for the best estimation of gels＇ elastic moduli by comparing the experimental bending curvatures with those computed from the beam model with preestimated moduli. Application to the measurement of the property of polyacrylamide gels indi- cates that the material compliance varies with the concentrations of bis-acrylamide, and the gels become softer after being immersed in a culture medium for a period of time, no matter to what extent they are polymerized.

Non-decoloured In-gel Digestion of Coomassie Blue-stained Proteins

A simplified method is presented for tryptic digestion of Coomassie brilliant blue(CBB)-stained proteins in polyacrylamide gels. Compared with conventional methods, the proposed method does not require a removal of the dye before digestion, and is thus faster and saves a lot of labor. The resulted digest can be analyzed by either RPLC/ESIMS or MALDI MS for identification of the protein in a conventional way. Model studies with bovine serum albumin(BSA) showed that 50 ng of the protein could be routinely identified. The simplified procedure displays a tendency to produce more incompletely cleaved peptides, which is favorable for improving the sequence coverage.

Characterization of Agro-diversity by Seed Storage Protein Electrophoresis:Focus on Rice Germplasm from Uttarakhand Himalaya,India

The characteristics of 48 rice varieties from Uttarakhand Himalaya, India were detected by morphological and biochemical markers. The grains of the selected rice varieties varied in their morphological （grain length, grain width and grain weight） and biochemical characters （sodium dodecyl sulfate polyacrylamide gel electrophoresis, SDS-PAGE）. Based on the presence of 70, 65, 60, 57, 37-39, 22-23, 13 and 10 kDa protein bands in the 48 rice varieties, seven types of profiles were identified. An unweighted pair group average method with arithmetic mean （UPGMA） dendrogram based on cluster analysis of genetic similarity of the protein bands showed two distinct groups with 1%-78% similarity coefficients. The presence of characteristic bands in selected varieties is a useful parameter for identification of rice germplasm.

Diagnosis of disease-specific proteins in cerebrospinal fluid of children infected with tuberculous meningitis

BACKGROUND： Isolated mycobacterium tuberculosis from cerebrospinal fluid （CSF） is regarded as the ＂gold standard＂ for diagnosis of tuberculous meningitis （TBM）. However, culture of CSF specimens is time-consuming and lacks sensitivity. There is a strong need to determine complementary disease-specific markers, which are essential for increasing early diagnosis and improving prognosis in patients with TBM OBJECTIVE： To establish proteomic profiles of CSF in TBM and normal children using two-dimensional polyacrylamide gel electrophoresis, and to screen for disease-specific proteins. DESIGN, TIME AND SETTING： The case-control study was conducted at the Department of Pediatrics, Xiangya Hospital of Central South University and the Key Laboratory of Cancer Proteomics of Ministry of Public Health of China between January 2008 and January 2009. PARTICIPANTS： The TBM group included three patients with a strongly positive tuberculin skin test, as well as positive CSF mycobacterial staining and culture, who were admitted to the Department of Pediatrics, Xiangya Hospital from January 2008 to January 2009. Three healthy, age- and gender-matched children served as the control group. METHODS： CSF proteins were separated using two-dimensional polyacrylamide gel electrophoresis in both groups. Gels were scanned using Image scanner and LabScan software. Differentially expressed proteins were analyzed using PDQuest 7.0 software. The clearly discernible spots, which were expressed only in the TBM group, were chosen to perform matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. MAIN OUTCOME MEASURES： Differentially expressed spots on CSF profiles of TBM and normal children were measured. RESULTS： Following comparison of two-dimensional polyacrylamide gel electrophoresis maps between TBM and control groups, 546 and 533 spots were detected, respectively. A total of 64 differentially expressed proteins were observed between the groups, including 15 upregulated spots, eight downregulated spots, 27 spots that were exclusively expressed in the TBM group, and 14 spots that were exclusively expressed in the control group. At total of 20 spots that were exclusively expressed in the TBM group were chosen for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, and 20 peptide mass fingerprints were obtained. After searching the data base, 16 proteins were matched. CONCLUSION： Two-dimensional polyacrylamide gel electrophoresis profiles of the CSF proteome were successfully established in the TBM and normal children. Parts of these differentially expressed proteins were identified through mass spectrometry and bioinformatics. Results indicated that apolipoprotein A I, anti-tumor necrosis factor-alpha antibody, crystal structure of MRP14 and HLA class II histocompatibility antigen DRB1-4 could be closely correlated with TBM pathogenesis.

Influences of La^(3+) Substitution on Structure and Electromagnetic Properties of Nanocrystalline Nickel Ferrites

Nanocrystalline nickel ferrites with substitution of Fe3+ by rare-earth La3+, according to the formula NiLaxFe2-xO4 (with x=0, 0.05, 0.1 and 0.15), were prepared by polyacrylamide gel method. Influences of the amount of La3+ substitution on the structure and electromagnetic properties of NiLaxFe2-xO4 compounds were systematically investigated by DSC-TG, XRD, TEM and wave-guide method. XRD results indicated that the pure spinel-type crystal structure of the NiLaxFe2-xO4 (x=0 and 0.05) was obtained at 500 ℃. TEM results showed that the average particle sizes of NiFe2O4 and NiLa0.1Fe1.9O4 particles were about 10 and 15 nm, respectively. The complex permittivity and complex permeability was measured in the frequency range of 8.2～12.4 GHz. The results revealed that the nanocrystalline NiLaxFe2-xO4 had both dielectric loss and magnetic loss in the frequency range of 8.2～12.4 GHz. The tgδε and tgδm of NiLaxFe2-xO4 (with x=0 and 0.05) decreased with the increase of La3+ ions content, and some strong resonance peaks of the tgδε and tgδm of NiLaxFe2-xO4 (with x=0.1 and 0.15) appeared because of the secondary phases (LaFeO3) and more lattice defects.

Preparation of Nanocrystalline Tin Dioxide Particles via the Acrylamide Polymerization Process

We report simple acrylamide polymerization process to prepare nanocrystalline tin dioxide(SnO_2) particles.A small amount of the so-called premix solution(monofunctional acrylamide and difunctional N,N'-methylenebisacrylamide) was mixed with the aqueous solution of Sn^(4+) in certain proportion,and a few drops of ammonium persulfate solution were added as initiator.When homogenized by magnetic stirring and heated to about 70℃,the mixed solution became a gel.This hydrous gel was directly decomposed by thermal treatment,resulting in obtaining rutile crystalline SnO_2 particles with a narrow size distribution typically in the range of 20 nm～40 nm.

Quasispecies groups in the core promoter region of hepatitis B virus

Objectives: To investigate the mutation of the basic core promoter (BCP) of hepatitis B virus (HBV) and clarify the significance of HBV quasispecies groups in patients with chronic HBV infection. Methods: A set of specific primers was synthesized according to the HBV DNA sequence of a Chinese strain. The BCP was amplified by PCR method from the serum of 40 patients with chronic HBV infection, and the PCR products of 2 patients were subcloned into pGEM Teasy vectors. Polyacrylamide gel elec- trophoresis (PAGE) was employed to display the de- letion mutations, and clones with differential length were selected to be sequenced. Sequence comparison was made to find the difference. Results: Two or three bands were displayed by PAGE in 60% patients. The results of sequence anal- ysis showed that there are some kinds of mutations in the BCP region. The substitution always occurs in TATA-like boxes, especially from T to C on 140 site. The deletion mutations were detected in TA1, TA2 and TA3. The 8bp, 20bp deletion mutations fre- quently happened. Conclusions: There is a hot deletion region in the BCP. The deletion and the substitution in the TATA- like box may influence the expression of preC/C pro- tein. The sequencing results indicate that there are HBV quasispecies groups in patients with chronic HBV infection.

Role of chelating agent in chemical and fluorescent properties of SnO_2 nanoparticles

A modified polyacrylamide gel route is applied to synthesize SnO2 nanoparticles. High-quality SnO2 nanoparticles with a uniform size are prepared using different chelating agents. The average particle size of the samples is found to depend on the choice of the chelating agent. The photoluminescence spectrum detected at λex = 230 nm shows a new peak located at 740 nm due to the surface defect level distributed at the nanoparticle boundaries.

Effect of Rare Earth on the Crystallization Behavior of Li_2O-Al_2O_3-SiO_2 Glass-ceramic

X-ray powder diffraction and Fourier transform infrared spectroscopy were applied for characterization of Li2O-Al2O3-SiO2 glass-ceramic powders doped with Eu2O3,Gd2O3 and Er2O3,respectively,in the conditions of different heat-treatment temperatures and with various amounts.The powders were derived from the polyacrylamide gel method.The results show that,the wet gels prepared by polyacrylamide perform a unique crystallization behavior in the process of drying,comparing with some customary preparation such as melt processing.The main crystal phase and crystallization sequence of Li2O-Al2O3-SiO2 micro-powders have no distinct with addition of Eu2O3,Gd2O3 or Er2O3,while the crystallization temperature of the β-spodumene decreased and the amount of the β-spodumene increased.

Differential Proteomic Analysis of Carbon Ion Radiation in Sheep Sperm

This study is first to investigate proteomic changes in sheep sperm induced by carbon ion radiation using two-dimensional electrophoresis （2-DE） analysis in the project of breeding a new variety of sheep. Differential expression proteins were detected using the PDQuest 8.0 software after staining with Coomassie blue. Valid spots were then analyzed through liquid chromatography tandem mass spectrometry （LC-MS/MS）. Among the 480 total protein spots displayed in 2-D gels, 6 specific protein spots were observed in sperm gels. A search against protein sequences in the National Center for Biotechnology Information databases （NCBI） indicated that differentially expressed proteins correspond to two proteins, identified to be enolase and transcription factor AP-2-alpha （TFAP-2c0. The two proteins were up-regulated in the irradiated sperm. To the best of our knowledge, this study is the first to identify proteomic changes induced by carbon ion radiation in sheep sperm. The analysis of differential expression protein may be useful in identifying new breeding markers in sheep reproduction and in clarifying the mechanisms involved in irradiation or space breeding.

Molecular characterization of yolk proteins in the female crab Neptunus pelagicus(A.Milne-Edwards,1861) from the Mediterranean Sea of Alexandria,Egypt

This study aimed to characterize the morphological changes in the ovary of the female crab Neptunus pelagicus and to identify specific fractions of vitelloginin and vitelline molecules during primary and secondary vitellogenesis.Samples of the blue crab were collected from the Mediterranean Sea of Alexandria monthly during 2017.Ovaries and oocytes in primary and secondary vitellogenesis were detached and treated for histological test.Native polyacrylamide gel electrophoresis(PAGE)Bis-Tris Gels was applied to identify vitelloginin(VN)and vitelline(VL)molecules.Protein Analyses were done by PAGE-SDS.The initial degenerate primers were built regarding the conserved amino acid domains of the yolk proteins.Primary and secondary vitellogeneses consisted of 8 phases.Lipoprotein fraction with molecular weight 550 kDa was identified in the hemolymph in secondary vitellogenesis.Two protein fractions(VLI&VLII)were identified in secondary vitellogenic oocytes.The electrophoresis performed with extract of stage I oocyte showed two protein fractions with molecular weights 550 kDa and 460 kDa.In stage II and III oocyte,4 subunits were presented of 180,195,140 and 120 kDa in VLI and 2 subunits with molecular weight of 110 kDa and 95 kDa in VLII.Another two fractions in stage V oocyte presented with molecular weights of 380 kDa and 360 kDa.Western blot analysis proved that both fractions were of four major polypeptide subunits with molecular weight of 180,125,90 and 85 kDa in each of the two VLs.The hybridization signal obtained by the Northern blot was detected in the hepatopancreas during ovarian cycle and in the ovary during secondary vitellogenesis.The result of the reverse transcription-polymerase chain reaction(RT-PCR)analysis showed that the mRNA that encodes the C-terminal region of the VN cDNA was found in the ovary in secondary vitellogenesis and in the hepatopancreas.

Construction and Preliminary Analysis of Ovine Oocytes Proteomic 2-DE Map

[Objective] To obtain ovine oocytes 2-dimensional gel electrophoresis （2-DE） maps. [Method] Ovine oocytes were solubilized in lysis buffer, and protein concentrations were measured using the method of Bradford and Ramagli. Then the samples were subjected to two-dimensional polyacrylamide gel electrophoresis. The 2-DE maps of ovine oocytes were analyzed through PDQuest 8.0. [Resait] The Ramagli method could re- flect concentration of oocyte protein more actually and could optimize the quantity of samples to get a 2-DE map with higher quality. The protein concentration measured by the Bradford method was higher than its actual value. [Coclusion] Each 2-DE map loading 700 oocytes is more reasonable.

Effect of high salinity on cell growth and protein production of Antarctic ice microalgae Chlamydomonas sp. ICE-L

Antarctic ice microalgae Chlamydomonas sp.ICE-L can survive and thrive in Antarctic sea ice.In this study,Chlamydomonas sp.ICE-L could survive at the salinity of 132‰ NaCl.SDS-PAGE showed that the density of 2 bands（26 and 36 kD） decreased obviously at the salinity of 99‰ NaCl compared to at the salinity of 33‰ NaCl.The soluble proteins in Chlamydomonas sp.ICE-L grown under salinity of 33‰ and 99% NaCl were compared by 2-D gel electrophoresis.After shocking with high salinity,8 protein spots were found to disappear,and the density of 28 protein spots decreased.In addition,19 protein spots were enhanced or induced,including one new peptide（51 kD）.The changes of proteins might be correlated with the resistance for Chlamydomonas sp.ICE-L to high salinity.

High-throughput Three-dimensional Gel Electrophoresis for Versatile Utilities: A Stacked Slice-gel System for Separation and Reactions (4SR)

A novel high-throughput system, called the stacked slice-gel system for separation and reactions （4SR）, was developed for the analysis of DNA/RNA and protein/peptide. The system provides a novel three-dimensional gel electrophoresis approach that exploits the property of stacked slice gels. It allows multiple samples simultaneously to react as well as to be separated, offering a two-dimensional （m×n） sample loading system. For this purpose, high-throughput multi-micro vessels （MMVs） containing variable numbers of wells （100 wells in this paper） have been used, which are made of 25 mm square-size polyacrylamide gels. Furthermore, after electrophoretic separation, a slice gel containing a desired sample can be easily removed and proceeded to the next step. Different biological reactions as well as successive separation of products were effectively carried out dealing with DNA/RNA and protein/peptide. It shows that this system has a diversity of potentials to be developed.