Infrared astronomy

The role and contributions of Frank McDonald in extending high energy astrophysics to the sub-eV photon energy range (in putting infrared astronomy into orbit) are discussed

Social Capital, Creative Destruction and Economic Growth

The dynamic structure of profit rates for 156 US manufacturing companies is analyzed by means of fractional integration techniques as an alternative to the commolny used ARMIA models with respect to the "persistence of profits". The results show - despite the short lengths of the series - that 35,5% of the series have long range dependence and 54% are nonstationary. This is a confirmation of the strong challenge to the competitive environment hypothesis obtained by previous studies.

Nahrung für alle? Biologische Landwirtschaft und Nahrungsmittelsicherheit in Entwicklungsländern

The global goal of ‘Food for All’, considered a fundamental human right by most of the countries, remains an unfinished item on the agenda of national governments and the international development community. In developing countries, household food insecurity is still widespread and its human and social consequences are most visible in rural areas. Poverty is one of the root causes for household food insecurity. Many poor people in rural areas directly or indirectly depend on small scale agriculture for their livelihood. At the same time, these people have limited access to livelihood securing assets that reduce their vulnerability to bio-physical, economic and social shocks. As the global interest in organic agriculture grows, an obvious question is to what extent the employment of organic agriculture principles and practices mitigate people’s vulnerability to food insecurity. The answer to this question is still contested, often political and influenced by the people’s beliefs and traditional position. For example, to agricultural experts and observers associated with conventional schools of thought, organic agriculture is associated with high labour cost and declining crop yields. According to this conventional proposition, organic agriculture results in temporal or permanent food shortages at household level. On the other side of the spectrum, agricultural experts and observers associated with alternative viewpoints on agricultural development argue that organic agriculture is a viable strategy that ensures household food security. Unfortunately both propositions are simplistic. By using examples from East Africa, the purpose of this presentation is to discuss the various linkages between organic agriculture and household food security. It seems that these linkages can be positive, neutral or negative. Based on the standard definition of household food security, which addresses three essential dimensions: the availability of food (i.e. sufficient agricultural production), access to food (i.e. the ability of obtain food for cash resources or in kind) and the proper utilisation of food (i.e. the ability to make use of available food for a balanced diet), a closer examination of the food security “equations” of organic agriculture is being conducted. This examination suggests that organic agriculture project philosophies and cultures have an impact on people’s availability, access and utilisation of food differently, hence food security “equations” vary across organic agriculture projects and schemes. Given the diverse food security implications of organic agriculture in developing countries, a fact that is hardly recognised by consumers in the industrialised countries, a plea for more research into the food security implications of organic agriculture is made. There is no doubt that organic agriculture in developing countries substantially contributes to the development of food security of small scale farmers. This household food security potential, however, is not always fully realised which may limit the contribution of organic agriculture towards the goal ‘Food for All’

The Role of Optimism and Working Alliance and its Utility in Predicting Therapeutic Outcomes in Counseling Relationships

Achieving positive therapeutic outcomes is the goal of all involved in the mental health field. The last 10 years have seen ever increasing demands for recognition of the elements that constitute empirically supported treatments (EST) and research on those elements, not only by professionals in the mental health field but also by third party providers (health insurance companies) and clients. Yet over the course of this increasing demand, research has repeatedly, and authoritatively, demonstrated that the most significant and consistent contributor to therapeutic outcome is the working relationship between client and counselor, not specific theoretically-bound techniques. In spite of the recognition of the importance of the working relationship, and the many efforts to isolate the ingredients that insure a therapeutic outcome, there is a dearth of consensus on those ingredients. With that lack of consensus in mind this research project sought to explore the interrelationship of three constructs in achieving therapeutic outcomes. The constructs that were investigated were dispositional optimism, the working alliance, and counselor experience. Participants were counselors who worked with clients presenting with depression. The research was conducted via an Internet based survey. Participants were asked to complete instruments that measured dispositional optimism and working alliance. The amount of counselors experience was determined via self-report on a demographic information sheet. The Working Alliance Inventory (WAI: Horvath & Greenberg, 1989) was used to measure perceived working alliance and the Life Orientation Test—Revised (LOT-R; Scheier, Carver, & Bridges. 1994) was used to measure dispositional optimism. Both instruments have evidence of validity and reliability in measuring the pertinent constructs, and are easily administered and scored. Upon completion of this study, statistical analyses were completed to determine the degree of relationship among the variables (dispositional optimism, perceived working alliance, and the amount of counselor\u27s experience). In addition to identifying potential relationships, multiple regression analysis was used to determine if either dispositional optimism or the working alliance was useful in the prediction of premature unilateral termination of therapy by clients. The results indicate that there is a statistically significant relationship among all three of the constructs studied herein. The results gave no support for the use of optimism or working alliance data as a means of predicting premature unilateral client termination. Implications of these results are discussed

In situ synthesis of size-controlled, stable silver nanoparticles within ultrashort peptide hydrogels and their anti-bacterial properties

We have developed a silver-releasing biomaterial with promising potential for wound healing applications. The material is made of ultrashort peptides which can self-assemble in water to form hydrogels. Silver nanoparticles (Ag NPs) were synthesized in situ within the biomaterial, using only UV irradiation and no additional chemical reducing agents. The synthetic strategy allows precise control of the nanoparticle size, with the network of peptide fibers preventing aggregation of Ag NPs. The biomaterial shows increased mechanical strength compared to the hydrogel control. We observed a sustained release of Ag NPs over a period of 14 days. This is a crucial prerequisite for effective anti-bacterial therapy. The ability to inhibit bacterial growth was tested using different bacterial strains, namely gram-negative Escherichia coli and Pseudomonas aeruginosa and gram-positive Staphylococcus aureus. Inhibition of bacterial growth was observed for all strains. The best results were obtained for Pseudomonas aeruginosa which is known for exhibiting multidrug resistance. Biocompatibility studies on HDFa cells, using Ag NP-containing hydrogels, did not show any significant influence on cell viability. We propose this silver-releasing hydrogel as an excellent biomaterial with great potential for applications in wound healing due to its low silver content, sustained silver nanoparticle release and biocompatibility

Synthesis and bioactivity of a conjugate composed of green tea catechins and hyaluronic acid

(-)-Epigallocatechin-3-gallate (EGCG) is a green tea polyphenol that has several biological activities, including anti-cancer activity and anti-inflammation. Hyaluronic acid (HA) is a naturally-occurring polysaccharide that is widely used as a biomaterial for drug delivery and tissue engineering due to its viscoelastic, biocompatible and biodegradable properties. By conjugating HA with EGCG, the resulting HA-EGCG conjugate is expected to exhibit not only the inherent properties of HA but also the bioactivities of EGCG. Toward this end, we report the synthesis of an amine-functionalized EGCG as an intermediate compound for conjugation to HA. EGCG was reacted with 2,2-diethoxyethylamine (DA) under acidic conditions, forming ethylamine-bridged EGCG dimers. The EGCG dimers were composed of four isomers, which were characterized by HPLC, high-resolution mass spectrometry and NMR spectroscopy. The amine-functionalized EGCG dimers were conjugated to hyaluronic acid (HA) through the formation of amide bonds. HA-EGCG conjugates demonstrated several bioactivities which were not present in unmodified HA, including resistance to hyaluronidase-mediated degradation, inhibition of cell growth and scavenging of radicals. The potential applications of HA-EGCG conjugates are discussed