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We developed a simple room-temperature synthetic route that achieves well-crystallized Pb100−xAgxSe alloy thin films by chemical bath deposition (CBD). The strategy provides a new paradigm to synthesize Ag doped PbSe thin films in one-step. We show that uniform distributed Pb100−xAgxSe thin films can be produced, whose crystal structure, morphology, and optical properties could be tailored with Ag concentration. With increasing x, both the shape and size of crystals are changing. Besides, the growth mechanism transits from cluster to ion by ion (IBI). The optical band gap (Eg) of the thin films is found to linearly increase with x values, from 0.26 eV to 0.31 eV. The density of states (DOS) and energy band structure of Pb100−xAgxSe are calculated using the first principle method. The calculation shows that Se 4p hybrids with Ag 4d at the valance band maximum, and the contribution to the conduction band minimum is mainly from Pb 6p and Ag 5s. The energy band gap shows the same tendency with Ag concentration as that in the experiment.

As it displays progressive hair-cell loss and degeneration of spiral ganglion neurons (SGNs) characterized by early-onset progressive hearing loss (ePHL), DBA/2J is an inbred mouse strain widely used in hearing research. Mouse nerve growth factor (mNGF), as a common exogenous nerve growth factor (NGF), has been studied extensively for its ability to promote neuronal survival and growth. To determine whether mNGF can ameliorate progressive hearing loss (PHL) in DBA/2J mice, saline or mNGF was given to DBA/2J mice of either sex by daily intramuscular injection from the 1st to the 9th week after birth. At 5, 7, and 9 weeks of age, in comparison with vehicle groups, mNGF groups experienced decreased auditory-evoked brainstem response (ABR) thresholds and increased distortion product otoacoustic emission (DPOAE) amplitudes, the prevention of hair cell loss, and the inhibition of apoptosis of SGNs. Downregulation of Bak/Bax and Caspase genes and proteins in cochleae of mice receiving the mNGF treatment was detected by real-time PCR, Western blot, and immunohistochemistry. This suggests that the Bak-dependent mitochondrial apoptosis pathway may be involved in the otoprotective mechanism of mNGF in progressive hearing loss of DBA/2J mice. Our results demonstrate that mNGF can act as an otoprotectant in the DBA/2J mice for the early intervention of PHL and, thus, could become of great value in clinical applications. © 2017 Wiley Periodicals, Inc.

Pritchett (World Bank Econ Rev 15(3):367–391, 2001) asked a famous question, “Where has all the education gone?” This brought the lack of correlation between the growth in measured education and the growth in income in developing countries to broad attention. Empirical findings confirm that after World War Two, human capital-output ratios have tended to be higher in less developed countries than in developed countries. We explain this pattern using a dynamic general equilibrium model with signaling games that explicitly considers the following: (1) workers with different abilities have different costs when choosing their educational levels, (2) employers are unable to directly observe workers’ abilities, and (3) worldwide governments broadly subsidize educational expenditure. Our simulation results suggest that modeling specifications with educational pooling and public subsidies to schooling could well mimic the related features of the data, and consequently these two factors could be especially important for explaining these features even though many other potential factors could also affect both economic growth and human capital accumulation simultaneously.

The national conference for college ideological and political work emphasizes that we should make good use of the main channel of classroom teaching, and that all kinds of courses should go with ideological and political theory courses in the same direction to form a synergistic effect. As a basic course in colleges and universities, college English will play an irreplaceable role in the process of "all staff, whole process and all-round education". By analyzing the significance of ideological and political education in college English course, this paper puts forward the idea of integrating ideological and political education into college English teaching. In order to realize the "ideology and politics course" in college English teaching, we should rely on the course of ideological and political education.

Background Toll like receptor 2 (TLR2) signaling can regulate the pathogenesis of otitis media (OM). However, the precise role of TLR2 signaling in OM has not been clarified due to the lack of an optimal animal model. Peptidoglycan–polysaccharide (PGPS) of the bacterial cell wall can induce inflammation by activating the TLR2 signaling. This study aimed at examining the pathogenic characteristics of OM induced by PGPS in Tlr2 −/− mice, and the potential therapeutic effect of sodium aescinate (SA) in this model. Methods Wild-type (WT) and Tlr2 −/− mice were inoculated with streptococcal PGPS into their middle ears (MEs) and treated intravenously with vehicle or SA daily beginning at 3 days prior to PGPS for 6 consecutive days. The pathologic changes of individual mice were evaluated longitudinally. Results In comparison with WT mice, Tlr2 −/− mice were susceptible to PGPS-induced OM. Tlr2 −/− mice displayed greater hearing loss, tympanic membrane damage, ME mucosal thickening, longer inflammation state, cilia and goblet cell loss. SA-treatment decreased neutrophil infiltration, modulated TLR2-related gene expression and improved ciliary organization. Conclusions PGPS induced a relatively stable OM in Tlr2 −/− mice, providing a new model for OM research. Treatment with SA mitigated the pathogenic damage in the ME and may be valuable for intervention of OM.

As it displays progressive hair-cell loss and degeneration of spiral ganglion neurons (SGNs) characterized by early-onset progressive hearing loss (ePHL), DBA/2J is an inbred mouse strain widely used in hearing research. Mouse nerve growth factor (mNGF), as a common exogenous nerve growth factor (NGF), has been studied extensively for its ability to promote neuronal survival and growth. To determine whether mNGF can ameliorate progressive hearing loss (PHL) in DBA/2J mice, saline or mNGF was given to DBA/2J mice of either sex by daily intramuscular injection from the 1st to the 9th week after birth. At 5, 7, and 9 weeks of age, in comparison with vehicle groups, mNGF groups experienced decreased auditory-evoked brainstem response (ABR) thresholds and increased distortion product otoacoustic emission (DPOAE) amplitudes, the prevention of hair cell loss, and the inhibition of apoptosis of SGNs. Downregulation of Bak/Bax and Caspase genes and proteins in cochleae of mice receiving the mNGF treatment was detected by real-time PCR, Western blot, and immunohistochemistry. This suggests that the Bak-dependent mitochondrial apoptosis pathway may be involved in the otoprotective mechanism of mNGF in progressive hearing loss of DBA/2J mice. Our results demonstrate that mNGF can act as an otoprotectant in the DBA/2J mice for the early intervention of PHL and, thus, could become of great value in clinical applications. © 2017 Wiley Periodicals, Inc.

As Chari et al. (2007) indicate, many growth theories explaining frictions in real economies are equivalent to a competitive economy, with some exogenous taxes. Using this idea, I developed an accounting method for identifying fundamental causes of economic growth. A two-sector neoclassical growth model with taxes is used as a prototype economy, and its equilibrium conditions define wedges. These wedges endogenously determine the long run growth rate, which is exogenous and not correlated with any other variables in a one-sector growth model. Furthermore, the importance of wedges in explaining the long-run growth rate can be evaluated through the use of a prototype economy. Applying this method to fifty countries reveals that, among seven wedges, two wedges that are respectively associated with the production function and the Euler equation for human capital are important in explaining economic growth.

A novel hybrid system (Zn4) containing a zinc bis(acylamidine) fluorescent dye covalently decorated with two photochromic dithienylethene (DTE) structures was prepared using a concise synthetic route. The photoregulated quenching of the fluorescence from the metal complex was achieved by reversibly switching the DTE component between its two isomers using UV and visible light. The fluorescence quenching can be attributed to intramolecular energy transfer, electron transfer or a combination of the two. Either process is only possible when the DTE is in its ring-closed form (Zn4b). The ring-open counterpart (Zn4a) lacks an absorption band in the visible region of the spectrum to accommodate energy transfer from the metallobis(acylamidine) to the photochromic DTE, and has an oxidation potential that is too large to match the reduction potential of the metal complex making electron transfer thermodynamically unfavourable. UV–vis absorption and emission spectroscopy demonstrated that the photoregulation of fluorescence has little effect on the photochromic process and the fluorescence could be turned “on” and “off” several times without the appearance of notable side products. The high contrast ratio (∼100:1) between the bright and dark states combined with the excellent thermal bistability make the hybrid an excellent candidate for potential use in non-destructive read-out and biological labeling applications, although several limitations need to be overcome (speed of photoswitching, and stability and solubility in water).

To study the expression of p-STAT3 and PTEN in human laryngeal squamous carcinoma, to explore their relations and clinical significance.Formalin-fixed and paraffin-embedded tissues from 67 cases of laryngeal squamous carcinoma, 25 cases of normal mucosa over 2.0 cm away from tumor margin in 25 patients with total or subtotal laryngectomy were evaluated for the expression of p-STAT3, PTEN by SP immunohistochemistry, the levels of these proteins in tissues and their correlation with clinicopathological parameters of laryngeal squamous carcinoma were analyzed. The prognostic analysis was performed by Kaplan-Merier.The expression rates of p-STAT3 protein in laryngeal squamous carcinoma and normal control laryngeal mucous tissues were 71.64%, 16% respectively. There was significant difference between them (Zc = 4.7052, P0.01); The expression rates of PTEN protein in laryngeal squamous carcinoma and normal control laryngeal mucous tissues were 41.79%, 96% respectively. There was significant difference between them (Zc = 5.7037, P0.01); The expressions of p-STAT3 and PTEN in laryngeal squamous carcinoma were associated with clinical stage, differentiation grade, lymph nodal metastases and prognosis (P0.01). There was a negative correlation between the expression of p-STAT3 and PTEN,and their correlation coefficient was r = -0.5148 (P0.01). p-STAT3 positive expression rate in patients survived over a 5 years follow up was 56.25% (18/32), which was obviously lower than the rate 82.35% (14/17) in those dead.The expression of p-STAT3 and PTEN may take important roles in the tumorigenesis, aggressiveness, metastases and prognosis of laryngeal squamous carcinoma. The high expression of p-STAT3 was negatively correlated with the lower PTEN in laryngeal squamous carcinoma, which suggested that PTEN may be a downstream target gene of p-STAT3.

To investigate the role and clinical value of the serum level of hepatocyte growth factor (HGF) and vascular endothelial growth factor(VEGF) in laryngeal squamous cell cancer and the relationship between HGF, VEGF and clinicopathological factors.We measured serum HGF and VEGF level in 54 laryngeal squamous cell cancer patients using ELISA to demonstrate the variation of HGF, VEGF level before operation and at day 1, 3, 7, 14 post-surgery. The concentration of the serum HGF, VEGF content in 35 normal healthy people and in 30 vocal cords polyps patients were measured by the quantitative sandwich enzyme linked immunoassay technique.(1) The level of serum HGF and VEGF in the patients with laryngeal squamous cell cancer was significantly higher than that of normal healthy people and vocal cord polyps patients (P0.01). (2) The level of serum HGF, VEGF in the patients with laryngeal squamous cell cancer was related to clinical stage, differentiation situation, lymph nodes metastasis (P0.01), but it was independent of age at diagnosis, gender and tumor location (P0.05). (3) There was a significantly positive correlation between preoperative serum VEGF and HGF levels (r = 0.7667, P0.01). (4) Post-operational serum HGF levels in 54 laryngeal squamous cell cancer patients who underwent surgical intervention increased significantly, peaked at day 3 after operation. Serum HGF levels of survivors during follow-up period gradually decreased at day 7 and day 14 after operation. The postoperative serum levels of VEGF were decreased significantly than that of preoperation.HGF and VEGF may play an important role in the development and progression of human laryngeal cancer. Elevated serum HGF and VEGF levels predict a more aggressive biological behavior in laryngeal squamous cell cancer.

To investigate the expression and clinical significance of Skp2 and PTEN in glottic carcinoma and the relationship between the two genes.Formalin-fixed and paraffin-embedded tissues, which came from 42 cases of glottic carcinoma and 16 cases of atypical hyperplasia of vocal fold and 27 cases of vocal cord polyp, were detected for the expression of Skp2, PTEN by SP immunohistochemistry, then we analyzed the result statistically.The expression rates of Skp2 protein in vocal cord polyp, atypical hyperplasia of vocal cord and glottic carcinoma were 11.11%, 37.50%, 40.48% respectively. There was significant difference among them (P0.01); the expression rates of PTEN protein in vocal cord polyp, atypical hyperplasia of vocal cord and glottic carcinoma were 100.00%, 75.00%, 52.38% respectively. There was significant difference among them (P0.05), the expressions of Skp2 and PTEN in glottic carcinoma were associated with clinical stage, lymph nodal metastases and prognosis (P0.05); there was a negative correlation between the expression of Skp2 and PTEN, and their correlation coefficient was r= -0.4301 (P0.01).The expressions of Skp2 and PTEN may play an important roles in the tumorigenesis, metastases and poor prognosis of glottic carcinoma. These changes may be the early molecular event of the carcinogenesis. The high expression of Skp2 was negative correlation with the lower PTEN in glottic carcinoma.