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We successfully synthesized Sr3Gd2(BO3)4:Eu3+ (SGBO:Eu3+) and Sr3Y2(BO3)4:Eu3+ (SYBO:Eu3+) phosphors through a high-temperature solid-state reaction. The structure was shown by x-ray powder diffraction and the irregular morphology of SGBO:Eu3+ and SYBO:Eu3+ phosphors was seen by a field emission scanning electron microscope. Additionally, the photoluminescence excitation spectra and emission spectra were also presented. As shown in the results, the phosphors could be stimulated by near ultraviolet light and then exhibited red light emission, which is consistent with the calculated color coordinates. The quenching concentrations of Eu3+ in SYBO and SGBO hosts are much higher than that in other borate hosts. In particular, far-red light-emitting at 702 nm due to the transition of 5D0 → 7F4 is beneficial to plant growth. The results show that the prepared samples have application value in white light emitting diodes.

Far red-emitting Mn4+ activated oxide phosphors based on the substitution of Mn4+ for Sb5+ in the lattice of Sr3LiSbO6 (SLSO) was prepared via solid state reaction process. The phases and micrographs of powders were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The luminescent properties of the samples with varying Mn4+ concentrations were investigated, and the result indicates that prepared phosphor SLSO:Mn4+ can be excited by (UV) light and exhibit intense far red emission at 698 nm. This emission band is well matched with the absorption band of phytochrome PFR. The mechanism of quenching concentration has been investigated. The thermal stability and thermal quenching concentration of SLSO:Mn4+ were discussed. In addition, the internal quantum efficiency (IQE) has been tested and calculated. All the above results suggest that the SLSO:Mn4+ phosphors have great potential applications in plant growth n-UV LEDs.

ALa9(SiO4)6O2: Eu3+ (A = Li, Na) oxyapatite phosphors have been synthesized via traditional solid-state methods X-ray powder diffraction (XRD) analysis confirmed the phase formation of ALa9(SiO4)6O2: Eu3+ (A = Li, Na) materials. The scanning electron microscope (SEM) image exhibited the irregular morphology of ALa9(SiO4)6O2: Eu3+ (A = Li, Na) particles. The photoluminescence excitation (PLE) and emission (PL) spectra were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light, and it exhibited red light emission. The calculated color coordinates lies in the red region. All the obtained results suggest that the prepared phosphors exhibit great potential application as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel red-emitting phosphor Ba 2 La 8 (SiO 4 ) 6 O 2 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of Ba 2 La 8 (SiO 4 ) 6 O 2 :Eu 3+ materials. The photoluminescence excitation and emission spectra, and the concentration dependence of the emission intensity of the phosphor were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The fundamental band gap energy (absorption edge) of Ba 2 La 8 (SiO 4 ) 6 O 2 , Ba 2 La 4.8 (SiO 4 ) 6 O 2 :3.2Eu 3+ and Ba 2 Eu 8 (SiO 4 ) 6 O 2 to be approximately 4.05 eV, 3.60 eV and 3.54 eV. The calculated color coordinates lies in the red region. Therefore, these obtained results suggest that the prepared phosphors exhibit great potential for use as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel red-emitting phosphor Ca 9 Na 0.667 Gd(PO 4 ) 7 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of Ca 9 Na 0.667 Gd(PO 4 ) 7 :Eu 3+ materials. The photoluminescence excitation (PLE) and emission (PL) spectra were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The calculated color coordinates lies in the red region. All the obtained results suggest that the prepared phosphors exhibit great potential application as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel red-emitting phosphor LiY 9 (SiO 4 ) 6 O 2 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of LiY 9 (SiO 4 ) 6 O 2 :Eu 3+ materials. The photoluminescence excitation and emission spectra, and the concentration dependence of the emission intensity of the phosphor were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The calculated color coordinates lies in the red region. Therefore, these obtained results suggest that the prepared phosphors exhibit great potential for use as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel blue-emitting apatite structure phosphate phosphor Sr5(PO4)2SiO4: Ce3+, Tb3+ has been synthesized by a high-temperature solid-state reaction. X-ray diffraction (XRD), scanning electric microscopy (SEM), ultraviolet–visible diffuse reflectance spectra (UV–Vis DRS), photoluminescence excitation (PLE) and emission (PL) spectra were utilized to characterize the samples. The results showed that the Sr5(PO4)2SiO4: Ce3+, Tb3+ samples exhibit a wide and strong emission band located at 405 nm. In addition, the process of energy transfer (ET) from Ce3+ to Tb3+ has been proved to be a dipole-dipole interaction. Importantly, the color of the phosphor emission can be changed by proper tuning of the Ce3+/Tb3+ ratio. Therefore, the prepared phosphors exhibit great potential for applications in the fields of luminescence and display.

A novel red-emitting phosphor La 0.67 Mg 0.5 W 0.5 O 3 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of La 0.67 Mg 0.5 W 0.5 O 3 :Eu 3+ materials. The photoluminescence excitation and emission spectra, the concentration dependence of the emission intensity, and decay curves of the phosphor were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The decay time was also determined for various concentrations of Eu 3+ in La 0.67 Mg 0.5 W 0.5 O 3 . The calculated color coordinates lies in the red region. Therefore, these obtained results suggest that the prepared phosphors exhibit great potential for use as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs)

Autofluorescence spectra and optical imaging of Platymonas subcordiformis after irradiation of diode laser were observed via laser scanning confocal microscopy (LSCM). With 488 nm Ar(+) laser excitation, the horizontal and vertical dimensions of a cup-shaped chloroplast of the irradiation group increased about 10% compared with the control group. The fluorescence spectra were similar between irradiation group and control group with a maximum fluorescence band around 682 nm, whereas the former has a higher intensity. Image of a small circular substance with stronger two-photon autofluorescence (TPA) was obtained when using two-photon excitation wavelength of 800 nm in single-channel mode. Further analysis by the 800 nm excitation based on two independent-channels mode showed an emission band of the small circular substance around 376-505 nm, which corresponded to the eyespot of P. subcordiformis. In lambda scanning mode, with two-photon wavelength of 800 nm excitation, six fluorescence peaks that are located at 465, 520, 560, 617, 660 and 680 nm were observed; the fluorescence intensity of the irradiation group was higher than that of the control group, especially at 520, 560 and 617 nm. As a conclusion, diode laser irradiation can promote chloroplast growth of P. subcordiformis cells in the form of expanding area and the increasing content of protein, phospholipids and chlorophyll. LSCM, especially TPA imaging based on femtosecond laser excitation, provides a nondestructive, real-time and accurate method to study changes of living algal cells under laser irradiation and other environmental factors.

In this paper, by analysing the axial cutting thickness and the cutting graphics, a new concept of cutting ratio K in vibration drilling is introduced for the first time. Cutting ratio K can show the proportion of cutting time in a cutting cycle and describe the working condition of the drilling during the vibration drilling. The relationship between cutting parameters and vibration parameters are denoted as two parameters, ωf and E. By computer program, the relationships between K and ωf is found; their characteristic are periodicity, symmetry and having many peak values. The curves, which describe the relation between K and E, are digressive. The regularity can be used to optimise the parameters in vibration drilling to achieve good machine performance. The experiment results indicate that the thrust, torque and the drill life are related to cutting ratio K.

It is well known that the no-chip machining process, burnishing, can easily improve surface roughness, waviness and hardness. To get the practical useful parameters, the effects of various burnishing parameters (spindle speed, depth, feed, burnishing radius and lathe) on surface roughness and waviness of the non-ferrous components were studied experimentally with a theoretical analysis. The experiments were conducted with a simply designed cylindrical surfaced polycrystalline diamond tool developed by us. It was found that smaller parameters do not mean lower surface roughness or waviness and different optimum burnishing parameters can be got under different burnishing conditions.

To compare the inflammation between wild BALB/c mice and mice with severe combined immunodeficiency (SCID) with endotoxemia induced by lipopolysaccharide (LPS).Endotoxemia models of wild and SCID mice were established by injecting LPS intraperitoneally. Serum was taken before and 3 h, 6 h, 12 h after injecting LPS, liver and lung were taken 12 h after injecting LPS. Alanine transarninase (ALT), aspartate aminotransferase (AST) and blood urea nitrogen (BUN) levels were measured by automatic biochemical analyzer. Liver and lung inflammation injury were observed by H.E staining. TNF-α, IFN-γ, IL-6 and MCP-1 levels in serum were detected by Cytometric Bead Array (CBA).(1) All of SCID mice (8/8) were dead at 12-24 h after injecting LPS, and only one BALB/c mouse (1/8) was dead. (2) ALT and AST levels of SCID mice 12 h after injecting LPS were higer than those of BALB/c mice(P0.05), but there was no difference of BUN levels between them. (3) The blind liver and lung pathology scores of SCID mice were higher than those of BALB/c mice (P0.05). (4) TNF-α, IFN-γ, IL-6 and MCP-1 levels in serum at 3 h, 6 h, 12 h after injecting LPS increased significantly, and the cytokine levels of SCID mice were higher than those of BALB/c mice(P0.05).SCID mice don't only excessively secrete inflammatory cytokines after injecting LPS, but also lead to more severe endotoxemia and inflammation injury of organs, which are the important cause of mouse death. The above results also show that the adjustment deficiency of adaptive immunoresponse, abnormal augmentation of innate immunoresponse may be an important cause of severe SIRS of endangering life.

Benign fibrous histiocytomas (BFH) represent a rare group of tumors with a common origin from the tissue histiocytes, often causing pain and space-occupying effect. BFH of bone causes diagnostic difficulties due to its atypical clinical symptoms, radiographic features and cytological characteristics, which can be easily confused with other benign lesions such as non-ossifying fibroma (NOF), giant cell tumor (GCT), and fibrous dysplasia. The lesions are prone to relapse, and the patients often show poor response to radiotherapy and chemotherapy, therefore radical lesion resection should be the therapeutic target of this disease. This paper reported a case of BFH involving the skull and reviewed the associated literatures.

Primary investigation of Platymonas subcordiformis was performed with laser scanning microscopic technology. Both autofluorescence spectra and autofluorescence imaging of Platymonas subcordiformis were achieved by one photon excitation of 488 nm Ar+ laser. Autofluorescence images revealed cup-shaped object inside the Platymonas subcordiformis cell, and the corresponding fluorescence peak located at 682 nm was attributed to chloroplast. Moreover, in single channel mode, there existed a round-shaped object in chloroplast center, showing strong fluorescence by 800 nm femtosecond laser excitation. Also, the authors obtained both the individual cup-shaped chloroplast and round-shaped object image and the overlaid images by using dual-channel mode. Meanwhile, six main fluorescence peaks were found. Single photon excitation can be used to obtain autofluorescence image and autofluorescence spectra of Platymonas subcordiformis, while two photon excitation combined with multitrack mode and Lambda mode can be used not only to observe internal structure, but also for the analysis of existence of biological and chemical substances with higher sensitivity than single photon excitation. LSCM technique can be a promising tool for rapid, convenient, real-time and effective investigation in ocean algae.

In this present paper, the microalgae irradiated by Nd:YAP laser are observed using Laser Confocal Scan microscope, and the auto fluorescence of microalgae cells is analyzed with quantitative analysis system, so as to investigate the effect of auto fluorescence alteration on growth of irradiated microalgae. Method: Platymonas subcordiformis, Phaeodactylum tricormutum and Isochyrsis zhanjiangensis are irradiated by Nd:YAP laser with 10w at 1341nm, irradiating time:12s, 30s, 35s and 55s. On Lambda Scan mode, the auto fluorescence images and fluorescence spectra of algae cells are obtained by the excitation 488nm (Ar+ laser). Result: there are two summit peaks, 489.8nm and 680.9nm, for Platymonas subcordiformis, Phaeodactylum tricormutum and Isochyrsis zhanjiangensis fluorescence spectrum. Contrast to the CK, the peak positions of fluorescence of irradiated algae cells is similar to the whole while the peak light intensity alters. On irradiation of promoting dose, however, the auto fluorescence intensity is enhanced more than control, with different type of microalgae, the different fluorescence intensity are shown in the analysis, and all of the microalgae pigment bodies change can be seen also. Conclusion: Physiological incentive effect of irradiated microalgae can be given expression on fluorescence characteristics and fluorescence intensity alteration of cells.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

FT-Raman spectroscopy was adopted to investigate the Raman spectrum of Platymonas subcordiformis. The result shows that the optimal experiment condition is making sample lose solvent with centrifuge, exciting laser power set at 360 mW and accumulating 70 times. The main peaks of the spectra are 381-432, 552-556, 611-613, 710, 873, 953-964, 1 108-1119, 1457, 1523-1527 and 2986 cm(-1). They belong to protein, insaturation acid and ester, etc, which are the main composition of Platymonas subcordiformis. The precise measurements of algae Raman spectra could be used for developing a new optical taxonomic methodology to distinguish between different algae species, and a rapid, non-destructive detection way of stress effects.

Raman spectrum of Platymonas subcordiformis was studied by FT-Raman spectroscopy. The results show that the optimum experiment conditions is that making sample lose solvent with centrifuge, excitation laser power for 360mW and accumulating 70 times. The main peaks of the spectrum are located at 556cm-1, 615cm-1, 880cm-1, 960 cm-1, 1112cm-1, 1457cm-1, 1523cm-1, 2986cm-1, respectively. These peaks can be assigned to protein, instauration acid and ester, etc., which are the main compositions of Platymonas subcordiformis. The precise measurements of algae Raman Spectroscopy could be used for biological samples research, such as developing a new optical taxonomic methodology to distinguish different algae species, and a rapid, non-destructive detection way of stress effects.

To construct hu-PBL/SCID chimeras and to investigate the development of lymphoma and oncogenicity of the Epstein-Barr virus (EBV).Human peripheral blood lymphocytes (PBLs) were isolated from healthy adult donors and transplanted intraperitoneally into severe combined immunodeficient (SCID) mice. Mice with hu-PBL engraftment from healthy EBV seronegative donors were injected intraperitoneally with EBV-containing supernatant from suspension culture of B95-8 cell line (active infection), whereas mice receiving lymphocytes from healthy EBV seropositive donors were not re-infected with B95-8 derived EBV (latent infection). Pathological examination and molecular analysis were performed on experimental animals and induced neoplasms.In the early stage of this experiment, 12 mice died of acute graft-versus-host disease, mortality was 34.3% (12/35 mice) with an average life span of 17.5 days. In 19 survival hu-PBL/SCID chimeric recipients from 12 healthy donors, tumor incidence was 84.2% (16/19 mice). The average survival time of tumor-bearing mice was 65.5 days. EBV-related neoplasms in SCID mice were nodular tumors with aggressive and fatal features. Histological morphology of tumors exhibited diffuse large cell lymphomas. Immunohistochemistry revealed that LCA (CD45) and L26 (CD20) were positive, but both PS1 (CD3) and UCHL-1 (CD45RO) were negative, and EBV products ZEBRA, LMP1, and EBNA2 were expressed in a small number of tumor cells. EB virus particles were seen in the nuclei of some tumor cells by electron microscopy, and EBV DNA could be amplified in the tumor tissues by PCR. In situ hybridization indicated that the nuclei of tumor cells contained human-specific Alu sequence.EBV-induced tumors were human B-cell malignant lymphomas. We obtained direct causative evidence dealing with EBV-associated tumor deriving from normal human cells.

We previously constructed human peripheral blood lymphocyte (hu-PBL)/severe combined immunodeficiency mouse (SCID) chimeras and induced human B-cell lymphomas associated with Epstein-Barr virus (EBV) in SCID mice. However, a number of SCID mice died of graft-versus-host disease (GVHD) during the early experimental course. The aim of this study was to test the efficacy of cyclosporine A (CSA) for prevention of GVHD and to define how CSA inhibits the occurrence of GVHD and the production of soluble interleukin (IL) 2 receptor (sIL-2R) in hu-PBL/SCID mice. No mouse died in the active EBV infection group with CSA administration, while 17 mice in three groups without CSA administration died of GVHD. Mortalities in these three groups were 55.56% (5/9), 30.43% (7/23), and 27.78% (5/18), and the medium life span was 17 days. Over the first 33 days after hu-PBL transplantation, serum level of human sIL-2R in hu-PBL/SCID chimeras was stable in the active EBV infection plus CSA group, while sIL-2R concentration gradually increased in the sera of mice with active EBV infection without CSA administration and peaked at 22 days. Thirty-two mice developed tumors among the 43 surviving SCID mice. There was no significant difference of tumor incidence between the active EBV infection groups with CSA and without CSA administration (P > 0.05). From their morphological and immunohistochemical features, as well as detection of human Alu-sequence and EBV in tumor cells, these EBV-induced tumors were identified as human B-cell lymphomas. Thus, CSA can strikingly inhibit GVHD in hu-PBL/SCID chimeras, and should therefore be effective to establish a stable SCID mouse model of human lymphoma associated with EBV. Treatment with CSA had no effect on the tumor incidence in hu-PBL/SCID chimeras after active EBV infection. Accordingly, serum level of sIL-2R is a valuable indicator of GVHD occurrence in hu-PBL/SCID chimeras.

A large number of callus from mature seeds of indica rice minghui 63 were obtained through pre-induction on medium with 2 mg/L 2,4-D but without inorganic and organic components for 9 days. Trichosanthin gene was transferred into indica rice minghui 63 by using agrobacterium with the help of bombardment and the transgenic plants were obtained by inducing regeneration. Southern and Western blot analysis showed that the trichosanthin gene had been transferred into genome of minghui 63 and expressed in rice plants. The anti-fungal assay suggested that transgenic rice plants enhanced resistance to infection of Pyricularia oryzae.

Background In neurosurgery, the most common type of facial and pharyngeal pain is trigeminal neuralgia. In contrast, glossopharyngeal neuralgia is relatively rare, and laryngeal neuralgia is the most rarely observed. Case presentation A case of laryngeal neuralgia combined with intermediate nerve neuralgia that was admitted to our hospital in May 2012 was reported here. The patient was a 58-year-old middle-aged female, who experienced 2 years of paroxysmal burning and stabbing pain near the thyroid perichodrium, in the skin covering the right front side of the neck, and deep in inner ear. Conclusion The surgical treatment plan similar to that for glossopharyngeal neuralgia could be applied if laryngeal neuralgia is associated with glossopharyngeal neuralgia and intermediate neuralgia or if no obvious improvement is achieved with the above mentioned treatment approaches.

This paper presents results of non-orthogonal three dimensional SEM investigations and wavelength spectrum analysis on the machined surface in turning with ultrasonic vibration in the cutting direction. The micromorphological and spectroanalytical comparisons are given between the ultrasonic vibration cutting and conventional turning.