Search

The industrial organization economics and the resource-based view of the firm have led to disagreements over the question as to which of firm performance at the industry and firm levels has persisted longer since the 1970s. Acknowledging that the IT industry in Taiwan has become very competitive and has demonstrated outstanding performance in the world since the 1990s, this study calculates the persistence in the incremental components of the effects on profitability, and tests hypotheses that conform to the above mainstream views of relative rates of persistence. A persistence partitioning model is fitted to a new data set, and the results show that the incremental effects of firms on profitability persist longer than the incremental effects of industry. In other words, the long-term competitive advantages of IT firms in Taiwan are more predictable and sustainable in regards to firm factors than for industry influences. These findings support the predictions of the resource-based view of the firm, and provide some implications for corporate strategy. [ABSTRACT FROM AUTHOR]

Well-aligned anatase (A)–TiO2nanocrystals (NCs) were grown by cold-wall metalorganic chemical vapor deposition (MOCVD) on fused silica using titanium-tetraisopropoxide (Ti(OC3H7)4) as the source reagent. Field emission scanning electron microscopy (FESEM) micrographs showed the growth of vertically aligned NCs. X-ray diffractometry (XRD) pattern revealed the aligned A–TiO2with a preferential orientation of (220). Raman spectrum confirmed the deposition of pure anatase phase TiO2on fused silica. Luminescence of self-trapped excitons and oxygen vacancies were observed in anatase NCs. The indirect band gap of A–TiO2was determined to be 3.14 ± 0.01 eV by analyzing the surface photovoltage spectrum. Energy-dispersive X-ray spectroscopy (EDS) and X ray photoelectron spectroscopy (XPS) analyses showed oxygen vs.titanium ratio of 2.0 ± 0.1 for the as-deposited TiO2NCs. Further structural characterization of the well-aligned A–TiO2NCs was studied using transmission electron microscopy (TEM) technique. The formation of building units bonded along {112} facets with preferred (220) orientation of the well-aligned A–TiO2NCs on fused silica were presented and the probable growth mechanisms were discussed. [ABSTRACT FROM AUTHOR]

Background: Cadmium (Cd), a common environmental heavy metal and endocrine disruptor, is known to exert toxic effects on the testes. However, the mechanisms accounting for its toxicity in mature spermatozoa remain unclear. Methods: Adult male C57BL/6 mice were orally administered with CdCl2 for 5 weeks at 3 mg·kg-1·day-1. Additionally, mouse spermatozoa were incubated in vitro with different doses of CdCl2 (0, 10, 50, 250 µM). Several sperm functions including the sperm motility, viability and acrosome reaction (AR) ratio were then examined. Furthermore, the current and expression levels of both the sperm-specific Ca2+ channel (CatSper) and the sperm-specific K+ channel (KSper) were evaluated by patch-clamping and western blotting, respectively. Results: Our data showed that the motility, viability and AR of sperm exposed to cadmium significantly decreased in vivo and in vitro. Interestingly, these changes were correlated with changes in CatSper but not KSper. Conclusion: The findings indicate sperm dysfunction during both chronic and acute cadmium exposure as well as a specific role for CatSper in the reproductive toxicity of cadmium.

Sperm respond to multiple chemical factors derived from the eggs and reorient their migratory direction – a process called chemotaxis. The chemotaxis of sperm in marine invertebrates has been established well. A couple of ion channels and enzymes are involved in the signal transduction pathway of sperm chemotaxis. In contrast, the mechanism of sperm chemotaxis in mammals is still rudimentary. Although much less is known about the chemotaxis of mammalian sperm, the feature of chemotaxis has been utilized to recruit sperm at the optimum functional state, which may improve the efficiency of assisted reproductive technology. In this review, we summarize potent chemoattractants and molecular regulatory mechanism in marine invertebrates and mammals and discuss the application of chemotaxis in clinical treatment.

This brief proposes possible a replacement of shallow p-n junction with insulated shallow extension (ISE) structure for bulk MOSFET. The shallow extension is defined by the sidewall thermal oxide rather than the implanted p-n junction. With this insulator for extension and main junction, a heavier halo doping concentration can be used. Thus, the threshold-voltage roll-off and the junction leakage current can be minimized simultaneously. This structure can be a good alternative for junction structures in sub-100-nm regimes. [ABSTRACT FROM AUTHOR]

Mg-doped Sb3Te films are proposed to improve the performance of phase-change memory (PCM). We prepare Mg-doped Sb3Te films and investigate their crystallization behaviors, structural, optical and electrical properties. We find that Mg-doping can increase the crystallization temperature, enhance the activation energy, and improve the 10-year data retention of Sb3Te. Especially Mg25.19(Sb3Te)74.81 shows higher Tc (∼ 190 °C) and larger Ea (∼ 3.49 eV), which results in a better data retention maintaining for 10 yr at ∼ 112 °C. Moreover Ra/Rc value is also improved. These excellent properties make Mg—Sb—Te material a promising candidate for the phase-change memory (PCM). [ABSTRACT FROM AUTHOR]

The implementation of instrumental analytical methods such as LC-MS for routine monitoring of toxins requires the availability of accurate calibration standards. This is a challenge because many toxins are rare, expensive, dangerous to handle, and/or unstable, and simple gravimetric procedures are not reliable for establishing accurate concentrations in solution. NMR has served as one method of qualitative and quantitative characterization of toxin calibration solution Certified Reference Materials (CRMs). LC with chemiluminescence N detection (LC-CLND) was selected as a complementary method for comprehensive characterization of CRMs because it provides a molar response to N. Here we report on our investigation of LC-CLND as a method suitable for quantitative analysis of nitrogenous toxins. It was demonstrated that a wide range of toxins could be analyzed quantitatively by LC-CLND. Furthermore, equimolar responses among diverse structures were established and it was shown that a single high-purity standard such as caffeine could be used for instrument calibration. The limit of detection was approximately 0.6 ng N. Measurement of several of Canada’s National Research Council toxin CRMs with caffeine as the calibrant showed precision averaging 2% RSD and accuracy ranging from 97 to 102%. Application of LC-CLND to the production of calibration solution CRMs and the establishment of traceability of measurement results are presented. [ABSTRACT FROM AUTHOR]

Microring resonators on silicon-on-sapphire (SOS) were characterized at 2.75 $\mu\hbox{m}$ wavelength. We obtained a $Q$ factor of 11400 $\pm$ 800. The thermo-optic coefficient of epitaxial silicon of SOS wafer was measured to be $2.11 \pm 0.08 \times 10^{-4}\ \hbox{K}^{-1}$. We also describe a characterization technique to measure the $Q$ of microring resonators using a fixed wavelength source. By only varying the temperature of the device, it is possible to measure the $Q$ of a mid-infrared (mid-IR) microresonator. The proposed method provides an alternative method of $Q$ measurement for microring resonators in mid-IR, where tunable lasers may not be easily available. The technique was used to determine the $Q$ of SOS microring resonators at 2.75 $\mu\hbox{m}$ wavelength.

We study the use of two-photon absorption (TPA) in a silicon optical waveguide for measuring the optical signal-to-noise ratio (OSNR) of a nonreturn to zero phase-shift keying (NRZ-PSK) signal. The average photocurrent generated in the silicon waveguide increased by 70 nA (from 375 to 445 nA) for a change in OSNR from 28 to 6 dB and a constant total input power of 10 dBm. The nonresonant nature of the silicon waveguide TPA detector enables the simple measurement of OSNR over a continuous wide (>; 10 nm) wavelength range. For a 10-Gb/s NRZ-PSK signal, we show that when the residual dispersion in the optical signal exceeds 425 ps/nm, further increases in dispersion have little effect on the photocurrent. Thus, this TPA-based OSNR monitor can be used in practical systems with large dispersion.

Purpose: To investigate the therapeutic effects of Cistanche deserticola Ma. extract (CDME) on ovariectomy-induced osteoporosis in rats. Methods: Female Sprague-Dawley rats were randomly assigned to a control group and five ovariectomy (OVX) subgroups, that is, OVX with vehicle (OVX), OVX with 17ß-estradiol (E2, 25 μg/kg/day), and OVX with CDME doses (40, 80, or 160 mg/kg/day). Daily oral administration of E2 or CDME started 4 weeks after OVX and lasted for 16 weeks. Bone mineral density (BMD) of L4 vertebrae and right femur of rats was estimated, The length of each femur was measured, and biochemical analysis of serum and urine specimens were performed. Results: CDME dose-dependently inhibited the reduction in BMD of L4 vertebrae (0.23 ± 0.02 g/cm3, p < 0.05) and femurs (0.20 ± 0.03 g/cm3, p < 0.05) caused by OVX and prevented the deterioration of trabecular microarchitecture (p < 0.05), which were accompanied by a significant decrease in skeletal remodeling (p < 0.05) as evidenced by the lower levels of bone turnover markers. Conclusion: This study indicates that CDME prevents OVX-induced osteoporosis in rats, and could be used for treating osteoporosis in elderly women. [ABSTRACT FROM AUTHOR]