Poly[[μ10-2,3-bis(carboxymethyl)butanedioato]disodium]

The asymmetric unit of the title compound, [Na2(C8H8O8)]n, contains one Na+ ion and half of a 2,3-bis(carboxymethyl)butanedioate (H2BTC2−) dianion, which lies on a center of symmetry. The dianion exhibits a μ10-bridging mode. Each Na atom lies in a NaO6 octa­hedron defined by six O atoms from five dianions. Adjacent NaO6 octa­hedra share a common O—O edge, generating a biocta­hedron; adjacent biocta­hedra are O—O edge-connected to one another, building up a chain along [001]. The chains are connected by adjacent H2BTC2− anions into a three-dimensional framework. The structure is further stabilized by O—H⋯O hydrogen bonds

Why do firms adopt stock options and who benefits? A natural experiment in China

A regulatory change in 2006, permitting equity compensations in China, offers a natural experiment to investigate drivers and outcomes of stock options. There are two unique features. First, adoption of stock options occurred rapidly compared to the US, where stock options have been around for more than 100 years with periods of high (1990s) and low (before 1950s) adoption. Second, stock options have been issued by state-owned enterprises (SOEs), an unusual aspect. This study analyzes all listed companies in China from 2004 to 2014, testing two competing theories: optimal contracting and managerial power. If managers own more equity, if the CEO also serves as board chairman and if compensation committees exist, managers are more likely to receive stock options. Ownership type and firm characteristics are also essential factors in granting stock options. In non-SOEs, evidence suggests that controlling shareholders award stock options less frequently but if they do they seem to induce managers to collude in tunneling. Applying a propensity score matching approach to account for an alleged self-selection bias, we do not observe any improvements in firm performance or shareholder value after stock options have been issued. Accordingly, managerial power seems to be the predominant driver for the introduction of stock options. Hence, managerial accountability and better disclosure are essential to ensure that stock options do contribute to value creation

Systems Thinking Applied to Higher Education Curricula Development

Systems Thinking (ST) is a general and yet nebulous term that describes an approach to understanding and working with complexity in the real world. ST seeks to evaluate different behaviors of individual system elements when they operate in isolation as opposed to when they are integrated as part of a larger system and placed within a particular operating environment. The education environment consists of multiple systems with different digital content, learning goals/outcomes that serve different stakeholders including teachers, learners, and administrators. The inherent complexity and interaction among these various educational system elements and functions make this environment a worthy candidate for consideration within the ST context. In this paper we examine the application of ST principles to higher education. Specifically, our study suggests that systems thinking methods and concepts can promote improved outcomes in curricula development with a positive impact on student learnin

Electrochemical Properties of Boron-Doped Diamond Electrodes Prepared by Hot Cathode Direct Current Plasma CVD

A series of boron-doped diamond (BDD) films were deposited by using a hot cathode direct current plasma chemical vapor deposition(HCDC-PCVD) system with different ratios of CH4/H2/B(OCH3)3 (trimethylborate) gas mixture. The morphology, structure and quality of BDD films were controled by SEM, XRD and Raman measurements. The electrochemical properties of the BDD films were investigated by electrochemical methods. Cyclic voltammetric performances of the BDD films indicated that the main determinant in the electrochemical characteristics of BDD films was the boron doping amount. The threshold potential for oxygen evolution increased from 1 V to 2.5 V. Meanwhile, the electrochemical potential window of BDD films was enlarged from 2.2 V to 4.5 V when the B content was increased from 1.75 × 1019cm-3 to 2.4 × 1021 cm−3. The cyclic voltammograms of BDD films in K4Fe(CN)6 and K3Fe(CN)6 mixed solution indicated that the behavior of Fe(CN)6-3/-4 redox couple could be regarded as semi-reversible

Plasma Orexin-A Levels in COPD Patients with Hypercapnic Respiratory Failure

Orexins have previously been shown to promote wakefulness, regulate lipid metabolism and participate in energy homeostasis. The aim of the study was to determine the relationship between plasma orexin-A and body composition in COPD in-patients with hypercapnic respiratory failure. 40 patients with hypercapnic respiratory failure and 22 healthy individuals were enrolled prospectively in this study. Plasma orexin-A levels, BMI, SaO2, PaCO2 and PaO2 were noted for all the patients. Plasma orexin-A levels were higher in the underweight (UW) group, normal weight (NW) group and overweight (OW) group of COPD patients as compared with UW, NW and OW group of the control group (P < .05). Plasma orexin-A in COPD patients were higher in the OW group than in the NW group and the UW group. Plasma orexin-A levels showed significant correlation with body mass index (BMI), independent of PaO2 (r = 0.576; P < .05) and %fat (r = 0.367; P < .05); a negative correlation was noted between plasma orexin-A levels and PaO2 (r = −0.738; P < .05) and SaO2 (r = −0.616; P < .05). Our results suggest that orexin-A levels are high in COPD patients with hypercapnic respiratory failure, and vary according to BMI and body composition. Orexin-A may be associated with the severity of hypoxemia in COPD patients with hypercapnic respiratory failure