Spatial trends of noncollinear exchange coupling mediated by itinerant carriers with different Fermi surfaces

We study the exchange coupling mediated by itinerant carriers with spin-orbit interaction by both analytic and numeric approaches. The mediated exchange coupling is noncollinear and its spatial trends depend on the Fermi-surface topology of the itinerant carriers. Taking Rashba interaction as an example, the exchange coupling is similar to the conventional Ruderman-Kittel-Kasuya-Yosida type in weak coupling. On the other hand, in the strong coupling, the spiral interaction dominates. In addition, inclusion of finite spin relaxation always makes the noncollinear spiral exchange interaction dominant. Potential applications of our findings are explained and discussed

Assessing the Effects of Acupuncture by Comparing Needling the Hegu Acupoint and Needling Nearby Nonacupoints by Spectral Analysis of Microcirculatory Laser Doppler Signals

We aimed to assess the effects of acupuncture by analyzing the frequency content of skin blood-flow signals simultaneously recorded at the Hegu acupoint and two nearby nonacupoints following acupuncture stimulation (AS). Laser Doppler flowmetry (LDF) signals were measured in male healthy volunteers in two groups of experiments: needling the Hegu acupoint (n = 13) and needling a nearby nonacupoint (control experiment; n = 10). Each experiment involved recording a 20 min baseline-data sequence and two sets of effects data recorded 0–20 and 50–70 min after stopping AS. Wavelet transform with Morlet mother wavelet was applied to the measured LDF signals. Needling the Hegu acupoint significantly increased the blood flow, significantly decreased the relative energy contribution at 0.02–0.06 Hz and significantly increased the relative energy contribution at 0.4–1.6 Hz at Hegu, but induced no significant changes at the nonacupoints. Also, needling a nearby nonacupoint had no effect in any band at any site. This is the first time that spectral analysis has been used to investigate the microcirculatory blood-flow responses induced by AS, and has revealed possible differences in sympathetic nerve activities between needling the Hegu acupoint and its nearby nonacupoint. One possible weakness of the present design is that different De-Qi feelings following AS could lead to nonblind experimental setup, which may bias the comparison between needling Hegu and its nearby nonacupoint. Our results suggest that the described noninvasive method can be used to evaluate sympathetic control of peripheral vascular activity, which might be useful for studying the therapeutic effects of AS

Regulation of axon repulsion by MAX-1 SUMOylation and AP-3.

During neural development, growing axons express specific surface receptors in response to various environmental guidance cues. These axon guidance receptors are regulated through intracellular trafficking and degradation to enable navigating axons to reach their targets. In Caenorhabditis elegans, the UNC-5 receptor is necessary for dorsal migration of developing motor axons. We previously found that MAX-1 is required for UNC-5-mediated axon repulsion, but its mechanism of action remained unclear. Here, we demonstrate that UNC-5-mediated axon repulsion in C. elegans motor axons requires both max-1 SUMOylation and the AP-3 complex β subunit gene, apb-3 Genetic interaction studies show that max-1 is SUMOylated by gei-17/PIAS1 and acts upstream of apb-3 Biochemical analysis suggests that constitutive interaction of MAX-1 and UNC-5 receptor is weakened by MAX-1 SUMOylation and by the presence of APB-3, a competitive interactor with UNC-5. Overexpression of APB-3 reroutes the trafficking of UNC-5 receptor into the lysosome for protein degradation. In vivo fluorescence recovery after photobleaching experiments shows that MAX-1 SUMOylation and APB-3 are required for proper trafficking of UNC-5 receptor in the axon. Our results demonstrate that SUMOylation of MAX-1 plays an important role in regulating AP-3-mediated trafficking and degradation of UNC-5 receptors during axon guidance

Sliding and pressure evaluation on conventional and V-shaped seats of reclining wheelchairs for stroke patients with flaccid hemiplegia: a crossover trial

<p>Abstract</p> <p>Background</p> <p>Reclining wheelchairs are commonly used to transport elderly stroke patients in Taiwan. However, there is concern that the patient's body in the wheelchair often slides forward when they return to a seated position, increasing the sitting pressure. Therefore, a novel reclining wheelchair with an ergonomic "V-Seat" was designed to prevent forward sliding and pressure sores. The use of these reclining chairs by stroke patients has not yet been studied. Thus, we investigated the effects of V-shaped and conventional seats in reclining wheelchairs on the extent of forward sliding and on the sitting pressure of stroke patients with flaccid hemiplegia and of able-bodied elders.</p> <p>Methods</p> <p>We recruited 13 able-bodied elders and 11 stroke patients with flaccid hemiplegia and performed 5 reclining cycles in both types of wheelchair. The amount of sliding along the backrest (BS) plane and the seat (SS) plane, the mean sitting pressure (MP), and the sacral peak pressure (SPP) of the subjects were recorded. We used the Wilcoxon signed-rank test to compare the BS, SS, MP, and SPP in wheelchairs with conventional and V-shaped seats, and we used the Wilcoxon rank sum test to compare the differences in BS and SS between stroke patients and able-bodied elders in both types of reclining wheelchair.</p> <p>Results</p> <p>The BS, SS, and SPP of stroke patients were significantly lower in the wheelchairs with V-shaped seats than in conventional wheelchairs in most comparisons; however, the BS of able-bodied elders was higher in V-shaped seats than in conventional seats. The SS and SPP of stroke patients were significantly higher than those of able-bodied elders in both types of reclining wheelchair, and the BS of stroke patients was significantly higher than that of able-bodied elders only in conventional reclining wheelchairs.</p> <p>Conclusions</p> <p>The use of V-shaped seats in reclining wheelchairs can help reduce the forward sliding and sacral peak pressure of stroke patients with flaccid hemiplegia. The back displacement of able-bodied subjects when using both conventional and V-shape seats in reclining positions differs from the back displacement of stroke patients with flaccid hemiplegia when using such seats. These results are of paramount value and should be considered when prescribing the use of reclining wheelchairs to subjects with flaccid hemiplegia.</p

Hepatitis B virus infection among pregnant women in Taiwan: Comparison between women born in Taiwan and other southeast countries

<p>Abstract</p> <p>Background</p> <p>Taiwan's national vaccination program has successfully decreased the prevalence of hepatitis B infection after twenty years of implementation and might be indirectly beneficial to the second generation. In this study, we compared the hepatitis B infection status of two groups: pregnant Taiwanese women and other Southeast Asian women, who because they had immigrated later in life to Taiwan by marriage to a Taiwanese man, had not been exposed to that vaccination program to evaluate the effect of hepatitis vaccination program on women of child-bearing age and further explored the potential impact of immigration on the hepatitis B public health policy in Taiwan.</p> <p>Methods</p> <p>Data was collected from 10,327 women born in Taiwan and 1,418 women born in other Southeast Asian countries, both groups receiving prenatal examinations at Fooyin University Hospital between 1996 and 2005. The results of serum hepatitis B s-Antigen (HBsAg) and hepatitis B e-Antigen (HBeAg) tests and other demographic data were obtained by medical chart review.</p> <p>Results</p> <p>The pregnant women from Taiwan had a higher HBsAg positive rate (15.5%) but lower HBeAg(+)/HBsAg(+) ratio (32.1%) than the women from other countries (8.9% and 52.4%). For those born before July, 1984, the period of no national vaccination program, Taiwanese women had a higher HBsAg positive rate than other Southeast Asian women (15.7% vs. 8.4%), but for women born after that day and before June 1986, the period of vaccination for high risk newborns, the HBsAg positive rates found to be slightly lower for Taiwanese women than for other Southeast Asian women (11.4% vs. 12.3%) and the difference was more significant (3.1% vs. 28.6%) after June 1986, the period of vaccination for all newborns. While the HBeAg(+)/HBsAg(+) ratios decreased with age in both groups, they were consistently higher in women from other Southeast Asian countries than in women born in Taiwan after age 20.</p> <p>Conclusion</p> <p>In Taiwan, the neonatal vaccination program that was implemented in 1984 has successfully reduced hepatitis B infection among pregnant women in present day, and is likely to indirectly prevent hepatitis B infection in the next generation. However, the increasing number of pregnant women from other Southeast Asian countries without a national neonatal vaccination program or with a program that was introduced later than the one in Taiwan will likely lessen the positive impact of this program and should be further assessed.</p

Src-homology 2 domain-containing tyrosine phosphatase 2 promotes oral cancer invasion and metastasis

BACKGROUND: Tumor invasion and metastasis represent a major unsolved problem in cancer pathogenesis. Recent studies have indicated the involvement of Src-homology 2 domain-containing tyrosine phosphatase 2 (SHP2) in multiple malignancies; however, the role of SHP2 in oral cancer progression has yet to be elucidated. We propose that SHP2 is involved in the progression of oral cancer toward metastasis. METHODS: SHP2 expression was evaluated in paired oral cancer tissues by using immunohistochemical staining and real-time reverse transcription polymerase chain reaction. Isogenic highly invasive oral cancer cell lines from their respective low invasive parental lines were established using a Boyden chamber assay, and changes in the hallmarks of the epithelial-mesenchymal transition (EMT) were assessed to evaluate SHP2 function. SHP2 activity in oral cancer cells was reduced using si-RNA knockdown or enforced expression of a catalytically deficient mutant to analyze migratory and invasive ability in vitro and metastasis toward the lung in mice in vivo. RESULTS: We observed the significant upregulation of SHP2 in oral cancer tissues and cell lines. Following SHP2 knockdown, the oral cancer cells markedly attenuated migratory and invasion ability. We observed similar results in phosphatase-dead SHP2 C459S mutant expressing cells. Enhanced invasiveness was associated with significant upregulation of E-cadherin, vimentin, Snail/Twist1, and matrix metalloproteinase-2 in the highly invasive clones. In addition, we determined that SHP2 activity is required for the downregulation of phosphorylated ERK1/2, which modulates the downstream effectors, Snail and Twist1 at a transcript level. In lung tissue sections of mice, we observed that HSC3 tumors with SHP2 deletion exhibited significantly reduced metastatic capacity, compared with tumors administered control si-RNA. CONCLUSIONS: Our data suggest that SHP2 promotes the invasion and metastasis of oral cancer cells. These results provide a rationale for further investigating the effects of small-molecule SHP2 inhibitors on the progression of oral cancer, and indicate a previously unrecognized SHP2-ERK1/2-Snail/Twist1 pathway that is likely to play a crucial role in oral cancer invasion and metastasis

Competition Conditions in Taiwan's Public Accounting Industry

[[abstract]]This paper investigates the degree of market competition in the public accounting industry of Taiwan over the period 1994-2008, using the ‘H statistic’ proposed by Panzar & Rosse (1987). Differing from previous works, this paper applies a newly developed model, i.e., the censored stochastic frontier (CSF) model, to test whether the audit market has achieved its long-run equilibrium. The model is superior to the conventional model that requires researchers adding a unity to the dependent variable of returns on assets (ROA) for all observations, forcing the transformed dependent variable to be non-negative. One can then take the natural logarithm of this dependent variable. Evidence shows that Taiwan’s accounting industry is characterized as monopolistic competition with a trend towards perfect competition. The result will help to build up the empirical model for public accounting industry. The CSF model confirms that this industry is already in a long-run equilibrium in the second half of the sample, which validates the use of the Panzar-Rosse model. Conversely, the employment of the conventional approach leads to a rejection of the long-run equilibrium over the entire sample period.[[notice]]補正完

Adsorption and thermal decomposition of H 2 S on Si(1 0 0)

Abstract Adsorption and thermal decomposition of H 2 S on Si(1 0 0)-2 Â 1 are studied by means of temperature-programmed desorption (TPD) and X-ray photoemission spectroscopy (XPS) with synchrotron radiation. The H 2 S molecule dissociates to form H and HS on the Si surface at adsorption temperature of 115 K. The Si(1 0 0)-2 Â 1 surface structure is conserved upon the adsorption of H 2 S due to bonding of dissociative H and HS on two Si atoms in a dimer without breaking the Si-Si dimer bond. H 2 and SiS are the only desorption products of thermal decomposition of H 2 S with peaks at 780 and 820 K, respectively. On the basis of TPD and XPS results, intermediates involved in decomposition of H 2 S and their adsorption configurations are proposed and discussed

Identification of critical virulence factors of fusobacterium nucleatum in promoting colorectal carcinoma

Background: The presence of an oral commensal, Fusobacterium nucleatum, in colorectal cancer(CRC) has been identified as an indicator of poor prognosis and has also been shown to increase gradually from stage I to IV. Several adhesion molecules in F. nucleatum, including RadD, FadA and Fap2, have been identified as virulence factors in CRC. However, given that F. nucleatum contains over 2,000 genes, it is possible that additional undiscovered pathogenic factors are contributing to F. nucleatum induced CRC stimulation.Aims: (1) Identification of potential pathogenic genes involved in CRC progression; (2) Evaluation of biofilm properties of clinical F. nucleatum isolates and their carcinogenicity in CRC cell line.Methods: (1) A F. nucleatum transposon library was created through EZ-Tn5 transposon mutagenesis. The catP transposon DNA fragment contains a chloramphenicol/thiamphenicol resistant cassette that can be used as a selection marker for the insertion. F. nucleatum mutant colonies were inoculated into 96-well plates and stored at -80°C in 100% glycerol. (2) Clinical F. nucleatum isolates were successfully identified from saliva samples of 101 oral squamous cell carcinoma (OSCC) patients and 158 non-OSCC patients at a positive rate of 10%. The overnight bacterial culture was adjusted to OD 0.1 and anaerobically incubated at 37°C in 24-well plates for 96 hours. Bacterial biofilm stability was determined by comparing the density of attached biomass before and after washing with 500µl of 1X PBS twice. 1x106 of HCT116, a CRC cell line, were seeded in 6-well plates for 24 hours and a “+” mark was scratched with 200µl pipette tips. Overnight bacterial culture was resuspended in McCoy’s 5a medium (no supplements or antibiotics). HCT116 cells were then infected with MOI 10 of various clinical F. nucleatum isolates. Cell migration rates were calculated based on the distance traveled in 24 and 48 hours.Results and conclusions: A transposon mutant library of 9,600 mutant colonies of F. nucleatum was established, with a minimum genome coverage of 99% achieved. This robust genetic tool will be used to identify novel virulence genes. Clinical isolates from both OSCC and non-OSCC patients demonstrated varying levels of biofilm stability and CRC cell migration. Further experiments, such as bacterial cell adhesion and invasion, as well as RNA sequencing, will be performed to expand the knowledge towards the development of novel OSCC prevention and treatment strategies