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Submicron periodic structures produced by femtosecond Ti:sapphire laser irradiation (1 kHz, 150 fs, 3–5 μm) on As2S3 and As35Se65 glasses at edges of damage holes are observed. Effects of changes in laser wavelength (λ), pulse number, power, and irradiation time on grating periodicity were studied. Regular groove-like ripples and distinct parallel submicron periodic gratings were seen in damaged areas. The damage grating period (Λ) is approximately λ/2n. The period increases with wavelength but is hardly influenced by irradiation time and pulse number. Samples with high refractive index and low bandgap are more prone to melting, and edge stripes are not obvious.

Advanced fabrication methods must be developed for magnetic–polymeric particles, which are used in medical diagnostics, drug delivery, separation, and environmental remediation. The development of scalable fabrication processes that enables simultaneously tuning of diameters and compositions of magnetic–polymeric particles remains a major challenge. Here, we proposed the production of high-quality magnetic-composite particles through a universal method based on the in-fiber Plateau–Rayleigh instability of polymeric fibers. This method can simultaneously control the particle diameter, hybrid configuration, and functional properties. The diameter of magnetic–polymeric particles can be reproducibly tuned from ∼20 nm to 1.25 mm, a wide range unachievable by conventional solution methods. The final diameter was controlled by the inner/outer fiber diameter ratio. We further showed that the prepared magnetic–polymeric composite particles can be used for the highly efficient recovery of heavy metals (98.2% for Cd...

In this work, we investigated a new procedure for preparation of purified As–Se glass. After drawing the fibers, an unclad fiber with minimum loss of 2.2 dB/m and a fiber coated with polyether sulfone with minimum loss of 4.2 dB/m were obtained. By pumping the unclad glass fiber in the normal dispersion region at 3 μm, the broadest supercontinuum generation spectrum, covering 1.6 μm to 11 μm with a 40 dB spectral flatness, was recorded from a 15 cm long fiber. The results showed that broadband SC covering nearly almost all transmittance of the material can be achieved with a pump laser in the normal dispersion region.

We have investigated the optimization parameters for polishing end-surface of chalcogenide glass fiber connector in the paper. Six SiC abrasive particles of different sizes were used to polish the fiber in order of size from large to small. We analyzed the effects of polishing parameters such as particle sizes, grinding speeds and polishing durations on the quality of the fiber end surface and determined the optimized polishing parameters. We found that, high-quality fiber end surface can be achieved using only three different SiC abrasives. The surface roughness of the final ChG fiber end surface is about 48 nm without any scratches, spots and cracks. Such polishing processes could reduce the average insertion loss of the connector to about 3.4 dB.

The applications of scintillating fiber in high-resolution medical imaging, remote radiation monitoring, and microbeam radiation therapy have raised a growing demand of bismuth-germanate (BGO) glass fiber. However, the task of construction of colorless BGO glass fiber has been met with limited success. Here, we present a renewable process that can help to achieve BGO scintillating fiber, based on glass relaxation and crystallization mediated dissolution of unexpected Bi center. The experimental results indicate that the strategy can improve the optical transmittance up to more than 73.17% at 483 nm, which is ∼6.28 times higher than that of the conventional material. Importantly, the obtained nanostructured BGO exhibits bright visible luminescence under excitation with X-ray. Furthermore, it can host various types of rare-earth dopants, and the radiation-induced luminescence can be tuned in a wide waveband region from visible to infrared waveband. In addition, colorless BGO fiber with bright emission is also successfully constructed, and the radiation probing test demonstrates the achievement of ∼19.48 times improvement in the detection sensitivity. Our results highlight the approach based on the dynamic glass relaxation may provide new opportunities for construction of scintillating glass fiber and compact radiation fiber detector.

A high-purity As 40 S 59 Se 1 /As 2 S 3 core/cladding step-index fiber for supercontinuum generation was fabricated in this study. The glass rods were obtained by using a relatively effective and inexpensive method of modified physical and chemical purification. Then, the multi-material fiber preform was fabricated through a modified laboratory using one-step co-extrusion process. Moreover, the fiber preform with a Polyether Sulfone (PES) polymer was drawn with a core diameter of ~ 22 μm. The core/cladding ratio of the fiber was approximately 1:17, and the minimum loss was approximately 1 dB/m between 4 and 6 μm. By pumping a 13 cm-long fiber with different laser powers and another two different lengths (20 cm and 50 cm, respectively) of fiber at 4.8 μm, a supercontinuum covering 1–5 μm could be recorded in all fibers. This study attained a 1–5 μm supercontinuum that covered the second atmospheric window. Result of this study can be a promising reference in the production of mid-infrared light source.

Objective Fibroblast growth factor (FGF) signaling is involved in articular cartilage homeostasis. This study was undertaken to investigate the role and mechanisms of FGF receptor 3 (FGFR-3) in the pathogenesis of osteoarthritis (OA) caused by surgery and aging in mice. Methods FGFR-3 was conditionally deleted or activated in articular chondrocytes in adult mice subjected to surgical destabilization of the medial meniscus (DMM). A mouse model of human achondroplasia was also used to assess the role of FGFR-3 in age-associated spontaneous OA. Knee joint cartilage was histologically evaluated and scored using the Osteoarthritis Research Society International system. The expression of genes associated with articular cartilage maintenance was quantitatively evaluated in hip cartilage explants. The effect of inhibiting Indian hedgehog (IHH) signaling in Fgfr3-deficient explants was analyzed. Results Conditional Fgfr3 deletion in mice aggravated DMM-induced cartilage degeneration. Matrix metalloproteinase 13 and type X collagen levels were up-regulated, while type II collagen levels were down-regulated, in the articular cartilage of these mice. Conversely, FGFR-3 activation attenuated cartilage degeneration induced by DMM surgery and age. IHH signaling and runt-related transcription factor 2 levels in mouse articular chondrocytes were up-regulated in the absence of Fgfr3, while inhibition of IHH signaling suppressed the increases in the expression of Runx2, Mmp13, and other factors in Fgfr3-deficient mouse cartilage explants. Conclusion Our findings indicate that FGFR-3 delays OA progression in mouse knee joints at least in part via down-regulation of IHH signaling in articular chondrocytes.

In this paper, we report 2 μm emission in bismuth germanate glasses doped with Ho3+/Tm3+ ions enhanced by surface plasmon resonance of Ag nanoparticles (NPs) under 800 nm laser excitation. We perform broadband mid-infrared emissions from 1700 nm to 2200 nm corresponding to Tm3+: 3F4 → 3H6 and Ho3+: 5I7 → 5I8 transitions. The energy transfer from Tm3+ to Ho3+ ions results in a strong 2030 nm emission. Results demonstrate that the emission intensity of the sample containing Ag NPs is much higher than that of the sample without Ag addition. For the best AgTH6 sample, the absorption and emission cross sections of Ho3+ transition (5I8 → 5I7) reach 0.5 × 10−20 cm2 at 1945 nm and 0.78 × 10−20 cm2 at 2030 nm, respectively. The comparative performances, i.e., σe × full width at half maximum and σe × τ, are approximately 129 × 10−20 cm2 nm and 24.8 × 10−24 cm2 s, respectively. Therefore, the glass has a potential application as 2.0 μm laser active media.

Near-infrared downconversion which can be used to improve the utilization of solar spectral has drawn much attention. In this work, chalcohalide glasses with compositions of 50GeS 2 –25Ga 2 S 3 –25CsCl (in mol.%): 0.1 wt.% Tm 2 S 3 - x wt.% Yb 2 S 3 ( x = 0, 0.1, 0.2, 0.3) were synthesized by vacuumed melt-quenching method. Absorption spectra, emission spectra, excitation spectra, and decay measurements were performed to prove the occurrence of cooperative energy transfer from the 1 G 4 level of Tm 3+ ions to two Yb 3+ ions. Quantum efficiency depends on Yb 3+ concentration is calculated, and the highest is 114.1%. The photon energy of Yb 3+ emission around 1 µm well matched with the operation band gap of the crystalline Si, so the glasses could potentially be applied in Si-based solar cell.

We reported the fabrication of submicron photonic crystal with As40Se40Te20 chalcogenide glass by resist-free thermal nanoimprint using a soft stamp. The As40Se40Te20 glass was prepared with melt-quenching method, and measured to have broad transmission range, high linear and nonlinear refractive index, and good thermal stability. Due to the very low glass transition temperature, the thermal nanoimprint was accomplished directly on the resist-free bulk glass with the soft stamp. By choosing suitable imprint condition, submicron chalcogenide glass photonic crystal with the band gap covering telecom wavelength was obtained. Taking advantage of the high nonlinearity of As40Se40Te20 glass, the imprinted PC structure may have potential applications for all-optical switch in optical communications.

Er3+-doped transparent glass ceramics containing micron-sized SrF2 crystals were obtained by direct liquid-phase sintering of a mixture of SrF2 powders and precursor glass powders at 820 °C for 15 min. The appearance and microstructural evolution of the SrF2 crystals in the resulting glass ceramics were investigated using X-ray diffraction, field-emission scanning electron microscopy and transmission microscopy. The SrF2 crystals are ~15 μm in size and are uniformly distributed throughout the fluorophosphate glass matrix. The glass ceramics achieve an average transmittance of 75% in the visible region and more than 85% in the near-IR region. The high transmittance of the glass ceramics results from matching the refractive index of the SrF2 with that of the precursor glass. Energy dispersive spectroscopy, photoluminescence spectra and photoluminescence lifetimes verified the incorporation of Er3+ into the micron-sized SrF2 crystals. Intense 2.7 μm emissions due to the 4I11/2 → 4I13/2 transition were observed upon excitation at 980 nm using a laser diode. The maximum value of the emission cross section of Er3+ around 2.7 μm is more than 1.2 × 10−20 cm2, which indicates the potential of using transparent glass ceramics containing micron-sized SrF2 crystals for efficient 2.7 μm lasers and amplifiers.

Chondrogenesis can regulate bone formation. Fibroblast growth factor receptor 3, highly expressed in chondrocytes, is a negative regulator of bone growth. To investigate whether chondrocyte FGFR3 regulates osteogenesis, thereby contributing to postnatal bone formation and bone remodeling, mice with conditional knock-out of Fgfr3 in chondrocytes (mutant (MUT)) were generated. MUT mice displayed overgrowth of bone with lengthened growth plates. Bone mass of MUT mice was significantly increased at both 1 month and 4 months of age. Histological analysis showed that osteoblast number and bone formation were remarkably enhanced after deletion of Fgfr3 in chondrocytes. Chondrocyte-osteoblast co-culture assay further revealed that Fgfr3 deficiency in chondrocytes promoted differentiation and mineralization of osteoblasts by up-regulating the expressions of Ihh, Bmp2, Bmp4, Bmp7, Wnt4, and Tgf-β1, as well as down-regulating Nog expression. In addition, osteoclastogenesis was also impaired in MUT mice with decreased number of osteoclasts lining trabecular bone, which may be related to the reduced ratio of Rankl to Opg in Fgfr3-deficient chondrocytes. This study reveals that chondrocyte FGFR3 is involved in the regulation of bone formation and bone remodeling by a paracrine mechanism.

The attenuated degradation of articular cartilage by cartilage-specific deletion of fibroblast growth factor receptor 1 (FGFR1) in adult mice suggests that FGFR1 is a potential target for treating osteoarthritis (OA). The goal of the current study was to investigate the effect of a novel non-ATP-competitive FGFR1 inhibitor, G141, on the catabolic events in human articular chondrocytes and cartilage explants and on the progression of cartilage degradation in a murine model of OA. G141 was screened and identified via cell-free kinase-inhibition assay. In the in vitro study, G141 decreased the mRNA levels of catabolic markers ADAMTS-5 and MMP-13, the phosphorylation of Erk1/2, JNK and p38 MAPK and the protein level of MMP-13 in human articular chondrocytes. In the ex vivo study, proteoglycan loss was markedly reduced in G141 treated human cartilage explants. For the in vivo study, intra-articular injection of G141 attenuated the surgical destabilization of the medial meniscus (DMM) induced cartilage destruction and chondrocyte hypertrophy and apoptosis in mice. Our data suggest that pharmacologically antagonize FGFR1 using G141 protects articular cartilage from osteoarthritic changes and intra-articular injection of G141 is potentially an effective therapy to alleviate OA progression.

Osteoarthritis (OA) in the temporomandibular joint (TMJ) is a common degenerative disease in adult, which is characterized by progressive destruction of the articular cartilage. To investigate the role of FGFR3 in the homeostasis of TMJ cartilage during adult stage, we generated Fgfr3f/f; Col2a1-CreERT2 (Fgfr3 cKO) mice, in which Fgfr3 was deleted in chondrocytes at 2 months of age. OA-like defects were observed in Fgfr3 cKO TMJ cartilage. Immunohistochemical staining and quantitative real-time PCR analyses revealed a significant increase in expressions of COL10, MMP13 and AMAMTS5. In addition, there was a sharp increase in chondrocyte apoptosis at the Fgfr3 cKO articular surface, which was accompanied by a down-regulation of lubricin expression. Importantly, the expressions of RUNX2 and Indian hedgehog (IHH) were up-regulated in Fgfr3 cKO TMJ. Primary Fgfr3 cKO chondrocytes were treated with IHH signaling inhibitor, which significantly reduced expressions of Runx2, Col10, Mmp13 and Adamts5. Furthermore, the IHH signaling inhibitor partially alleviated OA-like defects in the TMJ of Fgfr3 cKO mice, including restoration of lubricin expression and improvement of the integrity of the articular surface. In conclusion, our study proposes that FGFR3/IHH signaling pathway plays a critical role in maintaining the homeostasis of TMJ articular cartilage during adult stage.

The construction of cerium-doped materials is of great technological importance for various applications, including smart lighting, biological shielding and high-energy ray and particle detection. A major challenge is the efficient prevention of the undesired colorization after cerium doping. Here we present the nanocrystallization method for constructing colorless cerium-doped glass with extremely high cerium concentration (15 mol%). The structure and optical characterizations confirm that the notable color change of glass is associated with the precipitation of CeF3 crystalline phase during heat-treatment. The chemical state investigation shows that most of cerium ions exist in the form of Ce3+ in both the glass and glass-ceramic samples. The chemical environment study indicates a dramatic change in the local structure unit from -Ce-O- to -Ce-F-, which is believed to dominate the decoloring phenomenon in cerium doped glass. As a result, a significant improvement in the ultraviolet excited luminescence (~35 times enhancement in intensity) and scintillating performance can be achieved, pointing to potential applications in X-ray detection.

Fibroblast growth factor receptor 3 (FGFR3) participates in bone remodeling. Both Fgfr3 global knockout and activated mice showed decreased bone mass with increased osteoclast formation or bone resorption activity. To clarify the direct effect of FGFR3 on osteoclasts, we specifically deleted Fgfr3 in osteoclast lineage cells. Adult mice with Fgfr3 deficiency in osteoclast lineage cells (mutant [MUT]) showed increased bone mass. In a drilled-hole defect model, the bone remodeling of the holed area in cortical bone was also impaired with delayed resorption of residual woven bone in MUT mice. In vitro assay demonstrated that there was no significant difference between the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts derived from wild-type and Fgfr3-deficient bone marrow monocytes, suggesting that FGFR3 had no remarkable effect on osteoclast formation. The bone resorption activity of Fgfr3-deficient osteoclasts was markedly decreased accompanying with downregulated expressions of Trap, Ctsk, and Mmp 9. The upregulated activity of osteoclastic bone resorption by FGF2 in vitro was also impaired in Fgfr3-deficient osteoclasts, indicating that FGFR3 may participate in the regulation of bone resorption activity of osteoclasts by FGF2. Reduced adhesion but not migration in osteoclasts with Fgfr3 deficiency may be responsible for the impaired bone resorption activity. Our study for the first time genetically shows the direct positive regulation of FGFR3 on osteoclastic bone resorption. © 2016 American Society for Bone and Mineral Research.

Fibroblast growth factor (FGF) signaling is involved in articular cartilage homeostasis. This study was undertaken to investigate the role and mechanisms of FGF receptor 3 (FGFR-3) in the pathogenesis of osteoarthritis (OA) caused by surgery and aging in mice.FGFR-3 was conditionally deleted or activated in articular chondrocytes in adult mice subjected to surgical destabilization of the medial meniscus (DMM). A mouse model of human achondroplasia was also used to assess the role of FGFR-3 in age-associated spontaneous OA. Knee joint cartilage was histologically evaluated and scored using the Osteoarthritis Research Society International system. The expression of genes associated with articular cartilage maintenance was quantitatively evaluated in hip cartilage explants. The effect of inhibiting Indian hedgehog (IHH) signaling in Fgfr3-deficient explants was analyzed.Conditional Fgfr3 deletion in mice aggravated DMM-induced cartilage degeneration. Matrix metalloproteinase 13 and type X collagen levels were up-regulated, while type II collagen levels were down-regulated, in the articular cartilage of these mice. Conversely, FGFR-3 activation attenuated cartilage degeneration induced by DMM surgery and age. IHH signaling and runt-related transcription factor 2 levels in mouse articular chondrocytes were up-regulated in the absence of Fgfr3, while inhibition of IHH signaling suppressed the increases in the expression of Runx2, Mmp13, and other factors in Fgfr3-deficient mouse cartilage explants.Our findings indicate that FGFR-3 delays OA progression in mouse knee joints at least in part via down-regulation of IHH signaling in articular chondrocytes.

White matter injury characterized by damage to myelin is an important process in hypoxic-ischemic brain damage (HIBD). Because the oligodendrocyte-specific isoform of neurofascin, neurofascin 155 (NF155), and its association with lipid rafts are essential for the establishment and stabilization of the paranodal junction, which is required for tight interaction between myelin and axons, we analyzed the effect of monosialotetrahexosyl ganglioside (GM1) on NF155 expression and its association with lipid rafts after HIBD in Sprague-Dawley rats, weighing 12-15 g, on day 7 post-partum (P7; N = 20 per group). HIBD was induced on P7 and the rats were divided into two groups: one group received an intraperitoneal injection of 50 mg/kg GM1 three times and the other group an injection of saline. There was also a group of 20 sham-operated rats. After sacrifice, the brains of the rats were removed on P30 and studied by immunochemistry, SDS-PAGE, Western blot analysis, and electron microscopy. Staining showed that the saline group had definite rarefaction and fragmentation of brain myelin sheaths, whereas the GM1 group had no obvious structural changes. The GM1 group had 1.9-2.9-fold more GM1 in lipid rafts than the saline group (fraction 3-6; all P < 0.05) and 0.5-2.4-fold higher expression of NF155 in lipid rafts (fraction 3-5; all P < 0.05). Injection of GM1 increased the content of GM1 in lipid rafts as well as NF155 expression and its lipid raft association in HIBD rat brains. GM1 may repair the structure of lipid rafts, promote the association of NF155 (or other important proteins) with lipid rafts, stabilize the structure of paranodes, and eventually prevent myelin sheath damage, suggesting a novel mechanism for its neuroprotective properties.

Six cathepsin D isozymes have been purified from porcine spleen using a large scale purification procedure. Five isozymes, I to V, have an identical molecular weight of 50,000 and are similar in specific activity. Isozymes I to IV contained two polypeptide chains each. The light and heavy chains have Mr = 15,000 and 35,000, respectively. Isozyme V is a single polypeptide. The molecular weight of the sixth isozyme is about 100,000 and it has only 5% of the specific activity of the other isozymes. On Ouchterlony immunodiffusion, an antiserum formed precipitin lines against the urea-denatured isozyme with Mr = 100,000. This immunoreactivity showed immunoidentity with those formed against other isozymes. The NH2-terminal sequence of light chains was identical for the isozymes. This sequence is homologous to the NH2-terminal sequence of other acid proteases, especially near the region of the active center aspartate-32. The NH2-terminal sequence of the single chain, isozyme V, Is apparently the same as the light chain sequence. The NH2-terminal sequence analysis of the heavy chain from isozyme I produced two sets of related sequences, suggesting the prescene of structural microheterogeneity. The carbohydrate analysis of the isozymes, the light chain, and the heavy chain revealed the presence of possibly four attachment sites, with one in the light chain and three in the heavy chain. Each carbohydrate unit contains 2 residues of mannose and 1 residue of glucosamine. The results suggest that the high molecular weight cathepsin D (Mr = 100,000) is the probable precursor of the single chain (Mr = 50,000), which in turn produces the two-chain isozymes. These are likely in vivo processes.