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Formation of thaw loss cannot generally be avoided when meat is frozen and then thawed. Explanations have mainly focused on the damage to muscle fibers resulting from ice crystallization and the freezing-induced denaturation of myofibrillar proteins, the latter of which has, however, not received much research focus. This review discusses the relationship between myofibrillar protein denaturation and water-holding capacity of meat in freezing-thawing with the aim to improve the understanding the relative importance of protein denaturation in the formation of thaw loss. The contribution of decreased pH and high ionic strength in the unfrozen water in freezing is emphasized and we hypothesize that these two factors are causing protein denaturation and conformational changes within muscle fibers, and consequently loss of water-holding capacity. Slow freezing produces more thaw loss than fast freezing, and this is discussed here in relation to the impacts on myofibrillar protein denaturation induced by the freezing rate.

Layered van der Waals (vdW) crystals with intrinsic magnetic properties such as high Curie temperature (TC) and large perpendicular magnetic anisotropy (PMA) are key to the development and application of spintronic devices. The ferromagnetic vdW metal Fe3-xGeTe2 (FGT) has gained prominence recently due to its high TC (220 K) and strong PMA. Here, we introduce a new metallic vdW ferromagnets, Fe5-xGe2Te2 or FG2T, which was successfully synthesized and fully characterized. FG2T is a metal that orders ferromagnetically with a very sharp transition at 250 K (bulk and single crystal thin flakes) and shows large PMA, as found by both experimental and computational studies. This work enables novel heterostructure devices with near room temperature capabilities by using FG2T as spin injector.

In recent years, datasets represented in multi-view contain more information because different views describe different aspects. In fact, the structure of the dataset is embedded in a union of certain low-dimensional subspaces. Therefore, multiview subspace learning is a powerful technology to find the underlying structure and cluster data points correctly. Actually, the information contained in different views is different. Furthermore, the original data may be noisy. However, most existing multi-view subspace clustering methods treat each view equally and learn the self-expressiveness coefficient matrix of each view on the original data, which would decrease clustering performance. To solve the above problems, we propose a new method which learns a latent representation in an adaptive way. Meanwhile, the local geometrical structure is maintained on the latent representation by graph regularization. At the same time, a basic subspace clustering method is performed on the latent representation to get self-expressiveness coefficient matrix. We formulate the above problems into a unified optimization framework. Experimental results on several real-world datasets show the effectiveness of the proposed method.

The well-known BaAl4-type structure consists of three ordered ternary derivatives, i.e., BaNiSn3-(I4mm), ThCr2Si2-(I4/mmm), and CaBe2Ge2-type (P4/nmm). Few systems, such as Ba-Au-Sn, have been confirmed to manifest all three types as a function of valence electron count. In this work, the SrAuxSn4-xsolid solution at the 600 ° C section was studied thoroughly using both single crystal and powder X-ray diffraction. The crystal structures and phase width for the CaBe2Ge2-type SrAuxSn4-xsolid solution were established to be α = 4.6528(2)-4.6233(3) Å and c = 11.3753(4)-11.2945(10) Å for x ≈ 1.65(1)-2.19(1). In the structure of SrAu2Sn2, no Au/Sn mixing was found, but for x < 2 compositions, Au/Sn mixings were only located at the Wyckoff 2α (3/4 1/4 0) site and for x > 2 compositions, at the 2b (3/4 1/4 1/2) site. Differential scanning calorimetry (DSC) analyses indicated that no phase transition occurred for the CaBe2Ge2-type SrAuxSn4-xphase up to 950 ° C. Attempts to synthesize the ThCr2Si2-and BaNiSn3-type SrAuxSn4-xphases under the same reaction conditions were unsuccessful, and the BaNiSn3-type phase could not be attained even at a pressure of 3 GPa. The instability of a BaNiSn3-type "SrAuSn3" was investigated by both DSC measurements and first principles electronic structure calculations.

Information disclosure quality is directly related to the effective level of capital market and investors’ protection. Enhancing information disclosure quality is an essential urgent demand of listed companies all over the world. In this paper, based on the data of Shenzhen Stock Exchange, general analysis and volatility analysis are made to assess the current situation and prospect of information disclosure quality of listed companies in China. Finally, we bring forward some improvement recommendations.

The ordered magnetic states of MnWO4 at low temperatures were examined by evaluating the spin exchange interactions between the Mn2+ ions of MnWO4 on the basis of first principles density functional calculations and by performing classical spin analysis with the resulting spin exchange parameters. Our work shows that the spin exchange interactions are frustrated within each zigzag chain of Mn2+ ions along the c-direction and between such chains of Mn2+ ions along the a-direction. This explains the occurrence of a spiral-spin order along the c- and a-directions in the incommensurate magnetic state AF2, and that of a uudd spin order along the c- and a-directions in the commensurate magnetic state AF1. The ferroelectric polarization of MnWO4 in the spiral-spin state AF2 was examined by performing Berry phase calculations for a model superstructure to find that the ferroelectric polarization occurs along the b-direction, in agreement with experiment., 30 pages, 10 figures, 4 figures

Corporate governance influences information disclosure quality of listed companies. This paper examines the relationship between information disclosure quality and corporate governance from share ownership structure, stuff composition, and duties performance. The empirical results based on 1758 data sample of Chinese-listed firms indicate that the quality of information disclosure is positively related to the proportion of the independent directors, and is negatively related to its square. By analysis the quadratic curve determined by independent directors, the optimal proportion is approximately 28%. The largest ownership, the change in share holding, and total remuneration are significantly positively related to disclosure quality. And the size of directors is significantly negatively related to disclosure quality. In addition, larger firms have more effective governance structure and may provide higher quality information report. Also there is significant difference of information quality among industries. Financial information quality is a part of information quality. The findings provide empirical evidence for corporate governance reform and benefit improvement of information disclosure quality.

Disclosure quality is very important to listed companies and capital market. Based on factor analysis method this paper presents a disclosure quality index that is well verified by the assessment results of Chinese Shenzhen Stock Exchange. The index focuses on three aspects: corporate governance, firm structure characteristics and financial situation. The index has three advantages compared with previous researches: number of factors is less than other measurement methods; all weights of the variables are objective and avoid subjective errors; the results may assist in determining the quality disclosure and explaining the variation of current and prospective extent.

Background Apoptosis plays a key role in cell death observed in neurodegenerative diseases marked by a progressive loss of neurons as seen in Alzheimer's disease. Although the exact cause of apoptosis is not known, a number of factors such as free radicals, insufficient levels of nerve growth factors and excessive levels of glutamate have been implicated. We and others, have previously reported that in a stable HT22 neuronal cell line, glutamate induces apoptosis as indicated by DNA fragmentation and up- and down-regulation of Bax (pro-apoptotic), and Bcl-2 (anti-apoptotic) genes respectively. Furthermore, these changes were reversed/inhibited by estrogens. Several lines of evidence also indicate that a family of cysteine proteases (caspases) appear to play a critical role in neuronal apoptosis. The purpose of the present study is to determine in primary cultures of cortical cells, if glutamate-induced neuronal apoptosis and its inhibition by estrogens involve changes in caspase-3 protease and whether this process is mediated by Fas receptor and/or mitochondrial signal transduction pathways involving release of cytochrome c. Results In primary cultures of rat cortical cells, glutamate induced apoptosis that was associated with enhanced DNA fragmentation, morphological changes, and up-regulation of pro-caspase-3. Exposure of cortical cells to glutamate resulted in a time-dependent cell death and an increase in caspase-3 protein levels. Although the increase in caspase-3 levels was evident after 3 h, cell death was only significantly increased after 6 h. Treatment of cells for 6 h with 1 to 20 mM glutamate resulted in a 35 to 45% cell death that was associated with a 45 to 65% increase in the expression of caspase-3 protein. Pretreatment with caspase-3-protease inhibitor z-DEVD or pan-caspase inhibitor z-VAD significantly decreased glutamate-induced cell death of cortical cells. Exposure of cells to glutamate for 6 h in the presence or absence of 17β-estradiol or Δ8, 17β-estradiol (10 nM-10 μM) resulted in the prevention of cell death and was associated with a significant dose-dependent decrease in caspase-3 protein levels, with Δ8, 17β-E2 being more potent than 17β-E2. Protein levels of Fas receptor remained unchanged in the presence of glutamate. In contrast, treatment with glutamate induced, in a time-dependent manner, the release of cytochrome c into the cytosol. Cytosolic cytochrome c increased as early as 1.5 h after glutamate treatment and these levels were 5 fold higher after 6 h, compared to levels in the untreated cells. Concomitant with these changes, the levels of cytochrome c in mitochondria decreased significantly. Both 17β-E2 and Δ8, 17β-E2 reduced the release of cytochrome c from mitochondria into the cytosol and this decrease in cytosolic cytochrome c was associated with inhibition of glutamate-induced cell death. Conclusion In the primary cortical cells, glutamate-induced apoptosis is accompanied by up-regulation of caspase-3 and its activity is blocked by caspase protease inhibitors. These effects of glutamate on caspase-3 appear to be independent of changes in Fas receptor, but are associated with the rapid release of mitochondrial cytochrome c, which precedes changes in caspase-3 protein levels leading to apoptotic cell death. This process was differentially inhibited by estrogens with the novel equine estrogen Δ8, 17β-E2 being more potent than 17β-E2. To our knowledge, this is the first study to demonstrate that equine estrogens can prevent glutamate-induced translocation of cytochrome c from mitochondria to cytosol in rat primary cortical cells.

Background Recent data indicate that excitotoxicity of high levels of neurotransmitter glutamate may be mediated via programmed cell death (apoptosis) and that it can be prevented in HT22 mouse hippocampal cells by various equine estrogens with Δ8,17β-estradiol (Δ8,17β-E2) being the most potent. In order to delineate the mechanism(s), glutamate-induced cell death of HT22 cells was assessed by measuring (a) DNA fragmentation in the presence or absence of 11 equine estrogens (components of the drug CEE); (b) cell death and (c) levels of anti-apoptotic (Bcl-2) and proapoptotic (Bax) proteins in the presence or absence of two equine estrogens, Δ8,17β-E2 and 17β-estradiol (17β-E2) by LDH release assay and Western blot analysis respectively. Results Glutamate treatment induced cell death was time and dose-dependent. After 18 to 24 h, glutamate induced DNA fragmentation and morphological characteristics of apoptotic cell death. DNA fragmentation and morphological changes induced by 10 mM glutamate were completely inhibited by some equine estrogens. Exposure of cells to various concentrations of glutamate, resulted in a significant increase in cell death associated LDH release that was time-dependent. Both Δ8,17β-E2 and 17β-E2 inhibited the glutamate-induced LDH release and cell death in a dose-dependent manner with Δ8,17β-E2 being 10 times more potent than 17β-E2. Western blot analysis indicated that glutamate also significantly decreased the levels of Bcl-2 and increased Bax levels. This glutamate-induced change in the ratio of Bcl-2 to Bax was reversed by estrogens with Δ8,17β-E2 being more potent. Conclusions In HT22 mouse hippocampal cells, glutamate induced apoptosis that was associated with DNA fragmentation, morphological changes and up-regulation of the pro-apoptotic protein Bax and down-regulation of the anti-apoptotic protein Bcl-2. This apoptotic process was differentially prevented by some equine estrogens with Δ8,17β-E2 being more potent than 17β-E2. Since HT22 cells lacked both glutamate and estrogen receptors, the neuroprotective effects of estrogens most likely involve both genomic and non-genomic mechanisms. Since Δ8-estrogens are less feminizing estrogens than 17β-E2, further chemical modifications of these Δ8-estrogens may provide more selective estrogens that will be useful in the prevention of neurodegenerative diseases such as Alzheimer's and Parkinson's in both aging men and women.