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Understanding the occupational characteristics of patients is not only related to patients' life and health, but also conducive to improving their happiness. However, there were no studies that had been conducted on the relationship between occupation characteristic and postoperative recovery in patients with spinal fractures. The purpose of this study was to explore the relationship between the occupation characteristics of patients with thoracolumbar fracture and the characteristics of disease injury, treatment, and recovery so as to reduce the incidence and improve postoperative rehabilitation.Patients (n = 719) with thoracolumbar fractures were recruited. Patients were grouped according to the characteristic of occupations: unemployed group (n = 299), white-collar worker group (n = 20), and blue-collar worker group (n = 400). Data were collected, including the characteristics, injury and treatment information, and the recovery records for 1 year after operation. One-way ANOVA analysis, χMale, high-falling injuries and single segment injury (mainly T 11, T 12 and L2) were common in patients with thoracolumbar fractures, especially in the blue-collar worker group (70.8%, 78.3%, and 85.4%). Compared with the unemployed group, the patients in the white-collar worker group and blue-collar worker group had a higher proportion of young patients, a higher height and weight, a lesser rate of hypertension or diabetes. One week after injury, 73.4% of patients underwent surgery, with the blue-collar worker group accounted for the largest proportion. One month after surgery, 77.1% of patients were able to get out of bed, with the white-collar worker group accounted for the largest proportion. In the postoperative recovery information, patients in the blue-collar worker group were more likely to have severe low back pain (OR = 2.023, 95% CI: 1.440-2.284) and pain-disturbed sleep (OR = 2.287, 95% CI: 1.585-3.299) than those who in the unemployed group.Blue-collar workers, with a high risk of thoracolumbar fracture, have a higher incidence of low back leg pain and pain-disturbed sleep in the recovery after thoracolumbar fracture surgery, and this requires more attention.

As a fundamental aging mechanism, cellular senescence causes chronic inflammation via the senescence-associated secretory phenotype (SASP). Theca-interstitial cells are an essential but little-studied component of follicle development in the ovarian microenvironment. In the present study, we observed significant cellular senescence in theca-interstitial cells and secretion of chemokine (C-C motif) ligand 5 (CCL5) by these cells during aging. Furthermore, we aimed to investigate whether and how senescence-associated secretory phenotype (SASP)-associated CCL5 may be involved in follicle development. Increased levels of CCL5 in the microenvironment of follicles attenuated preantral follicle growth, survival, and estradiol secretion. Oocyte maturation and the expression of zona pellucida 3 and differentiation factor 9 (GDF9) were also inhibited by CCL5. Granulosa cell apoptosis in follicles was promoted by CCL5, accompanied by the phosphorylation of nuclear factor-κB by CCL5 and inhibition of the PI3K/AKT pathway. These results suggest that SASP-associated CCL5 produced by senescent theca-interstitial cells may impair follicle development and maturation during ovarian aging by promoting granulosa cell apoptosis.

The morphology of the auroral oval is an important geophysical parameter that can be used to uncover the solar wind-geomagnetic field interaction process and the intrinsic mechanism. However, it is...

The primordial follicle assembly, activation and the subsequent development are critical processes for female reproduction. A limited number of primordial follicles are activated to enter the growing follicle pool each wave, and the primordial follicle pool progressively diminishes over a woman's life‐time. The number of remaining primordial follicles represents the ovarian reserve. Identification and functional investigation of the factors involved in follicular initial recruitment will be of great significance to the understanding of the female reproduction process and ovarian ageing. In this study, we aimed to study whether and how semaphorin 6C (Sema6c) regulated the primordial follicle activation in the neonatal mouse ovary. The attenuation of SEMA6C expression by SiRNA accelerated the primordial follicle activation in the in vitro ovary culture system. PI3K‐AKT‐rpS6 pathway was activated when SEMA6C expression was down‐regulated. And the LY294002 could reverse the effect of low SEMA6C expression on primordial follicle activation. Our findings revealed that Sema6c was involved in the activation of primordial follicles, and the down‐regulation of SEMA6C led to massive primordial follicle activation by interacting with the PI3K‐AKT‐rpS6 pathway, which might also provide valuable information for understanding premature ovarian failure and ovarian ageing.

A thin SiOyNx film was inserted below a conventional SiNx antireflection coating used in c-Si solar cells in order to improve the surface passivation and the solar cell's resistance to potential-induced degradation (PID). The effect of varying the flow ratio of the N2O and SiH4 precursors and the deposition temperature for the SiOyNx thin film upon material properties were systematically investigated. An excellent surface passivation was obtained on FZ p-type polished silicon wafers, with the best results obtained with a SiOyNx film deposited at a very low temperature of 130 °C and with an optical refractive index of 1.8. In the SiOyNx/SiNx stack structure, a SiOyNx film with ~6 nm thickness is sufficient to provide excellent surface passivation with an effective surface recombination velocity Seff

Fine particulate matter (PM2.5) pollution arouses public health concerns over the world. Increasing epidemiologic evidence suggests that exposure to ambient airborne PM2.5 increases the risk of female infertility. However, relatively few studies have systematically explored the harmful effect of chronic PM2.5 exposure on ovarian function and the underlying mechanisms. In this study, female C57BL/6J mice are exposed to filtered air or urban airborne PM2.5 for 4 months through a whole-body exposure system. It is found that PM2.5 exposure significantly caused the alteration of estrus cycles, reproductivity, hormone levels, and ovarian reserve. The granulosa cell apoptosis via the mitochondria dependent pathway contributes to the follicle atresia. With RNA-sequencing technique, the differentially expressed genes induced by PM2.5 exposure are mainly enriched in ovarian steroidogenesis, reactive oxygen species and oxidative phosphorylation pathways. Furthermore, it is found that increased PM2.5 profoundly exacerbated ovarian oxidative stress and inflammation in mice through the NF-κB/IL-6 signaling pathway. Notably, dietary polydatin (PD) supplement has protective effect in mice against PM2.5-induced ovarian dysfunction.These striking findings demonstrate that PM2.5 and/or air pollution is a critical factor for ovarian dysfunction through mitochondria-dependent and NF-κB/IL-6-mediated pathway, and PD may serve as a pharmaceutic candidate for air pollution-associated ovarian dysfunction.

The authors further investigate the conditional variance and the persistence of real exchange rate (RER) shocks between Germany and some core European Union (EU) members from January, 1973 through 2004. Using data for all EU15 countries, they test whether the enlargement of the Union has reduced the variability and the persistence of RER shocks between Germany and the rest of the members during the 1990s. They also examine the impact of the introduction of the euro on the variance and persistence of real exchange rate shocks. Finally, the authors extend the analysis to the new members who joined in May, 2004. The results have implications for the economic cost of joining the Union, as well as assessing the timing of the newest members to enter the eurozone.

The direct methanol fuel cell (DMFC) has been discussed recently as an interesting option for a fuel-cell-based mobile power supply system in the power range from a few watts to several hundred kilowatts. In contrast to the favoured hydrogen-fed fuel cell systems (e.g. the polymer electrolyte membrane fuel cell, PEMFC), the DMFC has some significant advantages. It uses a fuel which is, compared to hydrogen, easy to handle and to distribute. It also comprises a fairly simple system design compared to systems utilising liquid fuels (like methanol) to produce hydrogen from them by steam reforming or partial oxidation to finally feed a standard PEMFC. Nevertheless, many severe problems still exist for the DMFC, hindering its competitiveness as an option to hydrogen-fed fuel cells. This work reviews the major research activities concerned with the DMFC by highlighting the problems (slow kinetics of the anodic methanol oxidation, methanol permeation through the membrane, carbon dioxide evolution at the anode) and their possible solutions. Special attention is devoted to the steady state and dynamic simulation of these fuel cell systems.

SU ZHOU [*] This study examines the finite-sample bias of Johansen's [1991] likelihood ratio tests for structural hypotheses on cointegration relations among economic variables through the Monte Carlo experiments. It is found that the Johansen tests with small samples are biased toward rejecting the null hypotheses more often than what asymptotic theory suggests, even after the test statistics are adjusted by Sims's correction. A bootstrap method for obtaining problem-specific critical values for the tests is proposed It is shown that using the bootstrap procedure may substantially reduce the small-sample bias. An empirical application of the procedure is demonstrated. (JEL C12, C22) I. INTRODUCTION Since Nelson and Plosser [1982] discovered that most macroeconomic variables have a nonstationary time series structure, cointegration analysis has been substantially developed and widely applied in empirical studies in various areas of economics. Cointegration analysis offers a natural way to test for the existence of long-run relationships among nonstationary economic variables. A set of variables, [X.sub.t], is said to be cointegrated if these variables are individually nonstationary, but at least one linear combination of them, [z.sub.t] = [beta]'[X.sub.t], exists that is stationary. The vector [beta] is referred to as the cointegration vector. If [X.sub.t] is a cointegrated system, we may say that the variables in [X.sub.t] do not drift "too far" apart and there exists one or more long-run equilibrium relationships among these variables. Cointegration analysis mainly consists of three segments: Tests for the rank of cointegration, estimation of cointegration vectors, and tests for structural hypotheses suggested by economic theory. One of the most popular methods of cointegration analysis is the multivariate maximum-likelihood approach of Johansen [1988, 1991]. The Johansen approach yields trace statistics and maximal eigenvalue statistics for identifying the number of cointegration vectors and provides consistent maximum-likelihood estimates of the coefficients of cointegration vectors. In addition, Johansen [1991] and Johansen and Juselius [1990, 1992] develop the likelihood ratio tests for structural hypotheses, that is, the hypotheses of linear restrictions on the cointegration relations, with a multivariate error correction model. Johansen and Juselius [1990, 1992] have tabulated the asymptotic critical values for both the maximal eigenvalue and the trace tests. Also, Johansen [1991] has derived the asymptotic distributions of the test statistics for structural hypotheses. Their critical values from the asymptotic distributions have been extensively employed in the cointegration studies. Unfortunately, empirical studies of long-run (cointegration) relationships are limited by finite sample sizes. It could be misleading to draw conclusions based on a small sample study while using the asymptotic critical values, which are appropriate only for large samples. Cheung and Lai [1993] investigate the accuracy of Johansen and Juselius's asymptotic approximations by computing the finite-sample distributions of the maximal eigenvalue and the trace statistics; they find that the asymptotic critical values are more liberal than the finite-sample critical values. That is, using the asymptotic critical values, one would reject the null of no cointegration too often when the sample size of the data used is rather small. There have been a number of other studies examining the small sample performance of several popular estimation and testing procedures designed for cointegrated systems, including the Johansen approach. [1] However, as far as I know, none of the existing studies has systematically investigated the small sample performance of any test for structural hypotheses. The present study intends to fill this gap and thus expand this body of literature. There is an obvious reason that researchers have overlooked the small sample problem of the tests for structural hypotheses on cointegration relations. …

This paper examines the long-run validity of purchasing power parity (PPP) for four high-inflation countries. The method of Zivot and Andrews (1992) is employed to detect the time-series behavior of the exchange rates and consumer price indices of these countries. We find that these variables are integrated with some trend breaks. We then utilize these data to test PPP using Johansen's (1988) multivariate cointegration technique. The cointegration tests are conducted with the correction of the finite sample bias and the adjustment for trend breaks. The results are consistent with the argument that, during the recent floating exchange rate period, PPP holds well, at least in a weak form, in high-inflation countries where the general price level movement overshadows the factors causing deviations from PPP.