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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.

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).

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.

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.

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.

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.