Spectroscopic and Electrochemical Studies of Optically Active Bipyridyl Complexes

The tris(2,2'-bipyridine) complexes of ruthenium(II) and osmium(II) have been synthesised and optically resolved. The singly, doubly and triply reduced complexes have been prepared electrochemically and their circular dichroism and luminescence spectra have been measured. Investigation of the absorption, circular dichroism and luminescence spectra of the complexes and their reduced analogues strongly suggest that the added electrons are localised on the individual bipyridine ligands of the complexes. Hence the complexes are best formulated as [M(bipy)n(bipy-)3-n](n-1)+, where M = Ru, Os and n = 0, 1, 2 and 3. In addition, a chemical reduction technique using lithium metal has been developed. This has enabled the infrared spectra of the triply reduced complexes to be measured. The triply reduced ruthenium complex has been found to racemise in dry acetonitrile but is optically stable in dimethylformamide. This has been attributed to a weakening of the ligand field of bipyridine when it is reduced to the anion. Lithium 2,2'-bipyridinyl has been synthesised and complexed with the chiral co-ordinating ligands (-)-sparteine and R and S-tetra-N,N,N',N'-methyl propane-1,2-diamine whereupon its circular dichroism spectra have been measured. The tris(2,2'-bipyridine)iridium(III) complex has been synthesised and optically resolved and its hitherto unknown circular dichroism spectrum has been measured. The complex has been chemically reduced and in addition to the triply reduced complex the quadruply reduced complex has also been synthesised and their absorption and circular dichroism spectra have been measured. Investigation of the circular dichroism spectra again suggest that the added electrons are localised on the individual bipyridine ligands of the complexes

Are workers with a disability less productive or less understood? An empirical investigation from an entrepreneurial business planning perspective

This study investigated selected work-performance data of a large call centre using the entrepreneurial business planning paradigm as a theoretical framework and tested the hypothesis that levels of productivity would be different for each group between workers with a disability and workers without a disability. On five measures of productivity, no significant differences were discernible but on a sixth measure, length of employment, it was found that disability workers remained in employment significantly longer. These results strongly refute the &lsquo;intuitive wisdom&rsquo; that workers with a disability are less productive. The results support a growing body of corporate experience and descriptive research indicating that workers with a disability perform as well as or better than their non-disability colleagues. Yet workers with a disability remain disproportionately under-employed. The key to translating the growing evidence of this research into higher levels of employment of workers with disabilities will depend upon employers adopting an entrepreneurial approach to the planning of human resource management.<br /

Exploring the Sources of Design Innovations: Insights from the Computer, Communications and Audio Equipment Industries

Whereas business research has focused on the impact of design innovations on market response and financial performance, the sources of design innovations, as opposed to those of technological innovations, have largely escaped investigation. In this research, we examine the organizational, financial, and environmental drivers of design innovations and how they contrast to technological innovations. Our study utilizes a unique dataset encompassing a 10-year window of innovation output drawn from the computer, communications, and audio and video equipment manufacturing industries. Our results suggest that design innovations are driven primarily by investments in research and development and slack organizational resources. Interestingly, we find that design innovations are more prevalent in smaller but fast-growing markets as opposed to technology innovations, which are prevalent in larger markets. Contrary to expectations, we find no association between marketing investments and design innovations. Our research contributes to the extant business literature by considering the sources of design innovations separately from the sources of technology innovations. We also contribute to the literature by distinguishing design and technology patents, developing a deeper understanding of design innovation, and illuminating a lesser understood source of competitive advantage for firms

A distributed electrical model for superconducting nanowire single photon detectors

To analyze the switching dynamics and output performance of a superconducting nanowire single photon detector (SNSPD), the nanowire is usually modelled as an inductor in series with a time-varying resistor induced by absorption of a photon. Our recent experimental results show that, due to the effect of kinetic inductance, for a SNSPD made of a nanowire of sufficient length, its geometry length can be comparable to or even longer than the effective wavelength of frequencies contained in the output pulse. In other words, a superconducting nanowire can behave as a distributed transmission line so that the readout pulse depends on the photon detection location and the transmission line properties of the nanowire. Here, we develop a distributed model for a superconducting nanowire and apply it to simulate the output performance of a long nanowire designed into a coplanar waveguide. We compare this coplanar waveguide geometry to a conventional meander nanowire geometry. The simulation results agree well with our experimental observations. With this distributed model, we discussed the importance of microwave design of a nanowire and how impedance matching can affect the output pulse shape. We also discuss how the distributed model affects the growth and decay of the photon-triggered resistive hotspot

Social networks and barriers to ART adherence among young adults (18–24 years) living with HIV at selected primary health facilities of South-Western Uganda: A qualitative study

Background Young adults living with HIV (YALWH) struggle to maintain high levels of adherence to antiretroviral therapy (ART) because of numerous barriers. This study describes the social networks of YALWH (18–24 years), their barriers to ART adherence, and the perceived role of social networks in overcoming those barriers. Methods This study used a qualitative descriptive research design. Twenty-three (23) YALWH who were on ART for a period of greater than one (1) month and had consented to participate in the study were purposively selected from two primary health care facilities in southwestern Uganda. We held four (4) focus group discussions with the YALWH over 5 weeks between the 24th of July and 7th September 2020. Data were audio recorded, transcribed, and entered in Microsoft word 2010. Using the content analysis techniques, data were inductively coded and categories or themes developed. Results Most YALWH belonged to bonding (family, friends, and neighbors), followed by bridging (informal groups), and linking (health professionals) social networks, respectively. Most YALWH, irrespective of gender, had close connections with their mothers or elder sisters. The commonest form of bridging networks was informal community groups that provided financial services, whereas the linking ones comprised health professionals’ directly involved in HIV patient care such as nurses, counselors, and their affiliates (expert clients or clinic based peer supporters), who occasionally acted as bonding networks. Structural barriers to ART adherence (eg, stigma) were the most cited, followed by medication- (eg, pill burden), and patient-related barriers (eg, non-disclosure of HIV status). Bonding networks were perceived to help overcome patient, medication, and structural barriers to ART adherence. Bridging networks overcame structural and medication-related barriers to ART adherence. Linking networks were perceived to help overcome some health systems and medication-related barriers to ART adherence. Conclusion Bonding social networks seem to play a prominent role in overcoming numerous barriers to ART adherence compared with bridging and linking social networks