Production of pristine, sulfur-coated and silicon-alloyed germanium nanoparticles via laser pyrolysis.

Here we demonstrate production of three types of germanium containing nanoparticles (NPs) by laser pyrolysis of GeH4 and characterize their sizes, structures and composition. Pristine Ge NPs were fabricated with 50 standard cubic centimeter per minute (sccm) of GeH4 and 25 sccm of SF6 as a photosensitizer gas, while sulfur-coated Ge NPs were produced with 25 sccm of GeH4 and 50 sccm of SF6. The laser pyrolysis of SiH4/GeH4 mixtures produced Si1-xGex alloy NPs. Effects of key process parameters including laser intensity and gas flow rates on NP properties have been investigated. The ability of the laser pyrolysis technique to flexibly produce a variety of germanium-containing NPs, as illustrated in this study shows promise for commercial-scale production of new nanomaterials as high purity dry powders.

Capacity retention behavior and morphology evolution of SixGe1-x nanoparticles as lithium-ion battery anode.

Engineering silicon into nanostructures has been a well-adopted strategy to improve the cyclic performance of silicon as a lithium-ion battery anode. Here, we show that the electrode performance can be further improved by alloying silicon with germanium. We have evaluated the electrode performance of SixGe1-x nanoparticles (NPs) with different compositions. Experimentally, SixGe1-x NPs with compositions approaching Si50Ge50 are found to have better cyclic retention than both Si-rich and Ge-rich NPs. During the charge/discharge process, NP merging and Si-Ge homogenization are observed. In addition, a distinct morphology difference is observed after 100 cycles, which is believed to be responsible for the different capacity retention behavior. The present study on SixGe1-x alloy NPs sheds light on the development of Si-based electrode materials for stable operation in lithium-ion batteries (e.g., through a comprehensive design of material structure and chemical composition). The investigation of composition-dependent morphology evolution in the delithiated Li-SiGe ternary alloy also significantly broadens our understanding of dealloying in complex systems, and it is complementary to the well-established understanding of dealloying behavior in binary systems (e.g., Au-Ag alloys).

Effect of proprioceptive neuromuscular facilitation integration pattern and swiss ball training on pain and balance in elderly patients with chronic back pain.

[Purpose] The purpose of this study was to determine the effects of proprioceptive neuromuscular facilitation integration pattern (PIP) and Swiss ball training on balance and pain in elderly patients with chronic low back pain. [Subjects] Participants were randomly assigned to a PIP training (n=24) and a Swiss ball training group (n=24). [Methods] The training was performed for 30 minutes per day, three times a week for 6 weeks. Outcome measures included the mean velocity in the X and Y directions using the Good Balance System(®), functional reach test, timed up and go test, and visual analogue scale. [Results] After completion of training, mean velocity in the X and Y direction, and the functional reach test, timed up and go test, and visual analogue scale results showed statistically significant improvements in the PIP and Swiss ball training groups. However, there was no significant difference in the functional reach test, timed up and go test, and visual analogue scale results between the two groups. [Conclusion] This study indicated that PIP training improved the balance ability of elderly patients with chronic low back pain.

Quantitative proteomic analysis reveals that lipopolysaccharide induces mitogen-activated protein kinase-dependent activation in human microglial cells.

Microglial cells act as the first and main form of active immune defense in the central nervous system related to inflammation and neurodegenerative disease. Lipopolysaccharide (LPS) induces many genes encoding inflammatory mediators, including cytokines such as tumor necrosis factor-α, interleukin-1ß, (IL-1ß), and IL-6, chemokines, and prostaglandins in microglial cells. Quantitative proteomics methods with isobaric chemical labeling using tandem mass tags and 2D-nano LC-ESI-MS/MS were used to systematically analyze proteomic changes in microglia responding to LPS stimulation. As a result, we found that the expression level of 21 proteins in human microglial cells changed after activation. Among those, one of the strong mitogen-activated protein kinase (MAPK) regulator proteins, CMPK1 was highly upregulated after LPS stimulation in human microglial cells. We detected and validated upregulation of MAPK including ERK1/2, p38, and SAPK/JNK by immunohistochemistry and Western blotting. NFκB, strong transcription factor of CMPK1, was translocated to the nucleus from the cytosol by high contents screening after LPS stimulation. Taken together, we conclude that MAPK signaling plays an important role in LPS-induced human microglial activation related to inflammatory response.

A Thin In2 S3 Interfacial Layer for Reducing Defects and Roughness of Cu2 ZnSn(S,Se)4 Thin-Film Solar Cells.

Cu2 ZnSn(S,Se)4 (CZTSSe) has generated considerable research interest owing to its composition of abundant elements and excellent light-absorption properties. However, CZTSSe thin-film solar cells suffer from a considerable deficit in the open-circuit voltage (VOC ), which is mainly due to the severe interfacial recombination induced by the rough surface of CZTSSe and numerous physical defects. In this study, to improve the morphology and reduce the interfacial recombination, an In2 S3 passivation layer was introduced between the CZTSSe and CdS layers via a chemical bath deposition process, and the effects of the In2 S3 layer on the device performance were systematically examined by performing various electrodynamic analyses. The CZTSSe solar cells with thin In2 S3 layers exhibited impressive increases in VOC and conversion efficiency (from 7.33 to 9.24 %), due to the suppression of physical defects and the refined surface morphology resulting from filling the voids and pinholes. In addition, the nanoscale roughness of the In2 S3 /CZTSSe surface increased the number of nucleation sites for the CdS nuclei, which may reduce the activation energy of the heterogeneous nucleation. The presence of In2 S3 layer resulted in uniform growth of CdS without macroscopic CdS agglomerates (i. e., reduced roughness of full devices), which improved the quality of the interface. These findings confirmed that the reduction of physical defects and the improved deposition of the CdS layer enabled by the added In2 S3 passivation layer improved the device performance.

Clinical significance of proximal interphalangeal joint pain in patients with trigger fingers.

We investigated incidence, clinical features and surgical outcomes of trigger finger accompanied by proximal interphalangeal joint pain. One-hundred and seventy-nine consecutive patients with trigger finger who had A1 pulley release were recruited. Forty-two patients (24%) complained of proximal interphalangeal joint pain at the time of surgery. Symptom duration was investigated, and tenderness at the proximal interphalangeal joint was palpated. Range of motion and pain score of the affected finger were measured pre- and post-operatively. Bone scan was performed to identify joint lesions. A comparison of the results between the proximal interphalangeal joint pain group and the non-proximal interphalangeal joint pain group shows that the proximal interphalangeal joint pain seemed to result from long symptom duration and consequent joint pathology. The proximal interphalangeal joint pain was incompletely resolved after A1 pulley release. Thus, the surgical outcomes might be worse than expected in spite of resolution of painful clicking, especially when there was additional joint tenderness on palpation. Level of evidence: IV.

Extracellular signal-regulated kinase is involved in tumor necrosis factor-alpha-induced MUC5AC gene expression in cultured human nasal polyp epithelial cells.

OBJECTIVES: Mucus secretion and inflammatory cytokines are increased in cases of chronic sinusitis with polyp. In this study we initially investigated the localization of MUC5AC protein in human nasal polyps. We then examined whether tumor necrosis factor-alpha (TNF-alpha) induces MUC5AC gene expression and whether extracellular signal-regulated kinase (ERK) plays a role in TNF-alpha-induced MUC5AC gene expression in cultured human nasal polyp epithelial cells. Finally, we investigated whether MUC5AC and activated ERK are co-expressed in goblet cells. MATERIAL AND METHODS: Human nasal polyp epithelial cells were isolated and subcultured. Passage-2 polyp epithelial cells were treated with 10 ng/ml TNF-alpha. ERK involvement was determined by Western blotting and MUC5AC gene expression by reverse transcriptase polymerase chain reaction. An ERK kinase assay and an inhibitor study using PD98059 were also performed. Immunohistochemical staining using polyclonal MUC5AC antibody and a phospho-specific ERK antibody was done in nasal polyps. RESULTS: MUC5AC was found to be expressed in the majority of goblet cells in human nasal polyp epithelium. TNF-alpha induced MUC5AC gene expression, and ERK activation was found to be essential for TNF-alpha-induced MUC5AC gene expression in cultured human nasal polyp epithelial cells. In addition, both MUC5AC and activated ERK were co-expressed in goblet cells of human nasal polyp epithelium. CONCLUSIONS: TNF-alpha induces MUC5AC gene expression via ERK in cultured human nasal polyp epithelial cells.

Efficacy and clinical outcome of preimplantation genetic diagnosis using FISH for couples of reciprocal and Robertsonian translocations: the Korean experience.

OBJECTIVE: To evaluate the efficacy and clinical outcome of preimplantation genetic diagnosis (PGD) using fluorescence in situ hybridization (FISH) for couples with chromosomal translocations. METHODS: PGD using FISH was performed in 59 cycles of 43 couples with reciprocal translocations, and 11 cycles of 6 couples with Robertsonian translocations. The diagnostic and clinical data were reviewed in a series of 70 treatment cycles of 49 couples from January 2001 to June 2002 at Samsung Cheil Hospital, Korea. RESULTS: A total of 1408 oocytes were retrieved, and 938 (81.7%) out of 1148 matured oocytes were fertilized by intracytoplasmic sperm injection (ICSI). Single blastomere biopsy and FISH analysis were successfully carried out in 99.3% (890/896) and 94.4% (840/890), respectively. Among 193 normal or balanced embryos, 169 embryos were transferred in 64 cycles (91.4% per started cycle). Twenty clinical pregnancies including two ectopic pregnancies and three spontaneous miscarriages (28.6% per started cycle, 31.3% per transfer cycle, 40.8% per couple) were established. Of the three spontaneous miscarriages, one was karyotyped as normal, one had an unbalanced arrangement and one was tetraploid. One case of preterm twin delivery occurred and 16 healthy babies were delivered in 12 single and 2 twin pregnancies. CONCLUSION: The clinical outcome was successful in 28.6% (14/49) of the treated couples with translocations after PGD. The spontaneous abortion rate was significantly reduced from 95.8% (69/72) to 16.7% (3/18) in these couples.