We report on the generation of radially and azimuthally polarized Q-switched laser radiation and its application in material processing. The power levels were sufficiently high to study micro-hole drilling in different metals. Depending on the optical properties of the metal, either radial or azimuthal polarization shows the best efficiency and the effect is attributed to waveguiding. For steel, a comparison to linearly or circularly polarized laser radiation indicates that the doughnut-shaped beam with azimuthal polarization is the most energy-efficient in producing holes of the same diameter and depth.

ABSTRACT. With sustainability within food systems becoming an increasingly important issue, several approaches that claim to assess the sustainability of farms, farming systems, and supply chains have been developed. Looking more closely at these sustainability impact assessment approaches, we discerned considerable differences between them in terms of scope, the level of assessment, and the precision of indicators used for impact assessment. Our aim was to classify and analyze a range of available sustainability impact assessment approaches with respect to scope and precision. From a total of 35 sustainability assessment approaches, we selected 6 for a detailed comparison. From our analysis, we concluded that there are 3 different types of trade-offs in these approaches: between different kinds of scope, between different indicators for precision and trade-offs, and between the scope and precision. Thus, one-sizefits-all solutions, with respect to tool selection, are rarely feasible. Furthermore, as indicator selection determines the assessment results, different and inconsistent indicators can lead to contradictory assessment results that may not be comparable. To overcome these shortcomings, sustainability impact assessments should include a precise definition of the notion of "sustainability" along with a description of the methodological approach and the indicator sets and should aim for harmonization of indicators and assumptions. Global initiatives such as the Sustainability Assessment in Food and Agriculture Systems (SAFA) Guidelines are a helpful step toward shedding light on the differences of these approaches and making the assessment results more comparable.

Understanding how the local environment of a “single-atom” catalyst affects stability and reactivity remains a challenge. We present an in-depth study of copper1, silver1, gold1, nickel1, palladium1, platinum1, rhodium1, and iridium1 species on Fe3O4(001), a model support in which all metals occupy the same twofold-coordinated adsorption site upon deposition at room temperature. Surface science techniques revealed that CO adsorption strength at single metal sites differs from the respective metal surfaces and supported clusters. Charge transfer into the support modifies the d-states of the metal atom and the strength of the metal–CO bond. These effects could strengthen the bond (as for Ag1–CO) or weaken it (as for Ni1–CO), but CO-induced structural distortions reduce adsorption energies from those expected on the basis of electronic structure alone. The extent of the relaxations depends on the local geometry and could be predicted by analogy to coordination chemistry.

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Knowledge-related and organizational learning processes in alliances have received much attention throughout the last 25 years. The field has generated a rapidly growing body of empirical evidence on how knowledge is managed in alliances. However, the sphere is highly complex, fragmented, incoherent, and heterogeneous in terms of the theoretical approaches applied. This paper presents an integrative and organizing framework for the empirical literature on knowledge management in strategic alliances. It illustrates how the knowledge management outcomes of knowledge creation, transfer and application are determined by four distinct sets of factors: knowledge characteristics, partner characteristics, partner interaction, and active knowledge management. Based on this framework, this review analyses and integrates empirical evidence in order to identify where findings converge and where results conflict. So far, research has focused strongly on singular interrelations between these four sets of factors and the transfer of knowledge. Conversely, the questions of how knowledge is created, retained, retrieved and applied and how the interplay of the different factors affects knowledge management in strategic alliances remain widely unexplored. The review concludes with a summary of the current state of the art in empirical research and discusses some promising avenues for future investigation.

The application of microbial inoculants (biofertilizers) is a promising technology for future sustainable farming systems in view of rapidly decreasing phosphorus stocks and the need to more efficiently use available nitrogen (N). Various microbial taxa are currently used as biofertilizers, based on their capacity to access nutrients from fertilizers and soil stocks, to fix atmospheric nitrogen, to improve water uptake or to act as biocontrol agents. Despite the existence of a considerable knowledge on effects of specific taxa of biofertilizers, a comprehensive quantitative assessment of the performance of biofertilizers with different traits such as phosphorus solubilization and N fixation applied to various crops at a global scale is missing. We conducted a meta-analysis to quantify benefits of biofertilizers in terms of yield increase, nitrogen and phosphorus use efficiency, based on 171 peer reviewed publications that met eligibility criteria. Major findings are: (i) the superiority of biofertilizer performance in dry climates over other climatic regions (yield response: dry climate +20.0 ± 1.7%, tropical climate +14.9 ± 1.2%, oceanic climate +10.0 ± 3.7%, continental climate +8.5 ± 2.4%); (ii) meta-regression analyses revealed that yield response due to biofertilizer application was generally small at low soil P levels; efficacy increased along higher soil P levels in the order arbuscular mycorrhizal fungi (AMF), P solubilizers, and N fixers; (iii) meta-regressions showed that the success of inoculation with AMF was greater at low organic matter content and at neutral pH. Our comprehensive analysis provides a basis and guidance for proper choice and application of biofertilizers.

Psychiatric disorders were studied in an epidemiological and representative sample of 1964 pupils attending the first to ninth grade in various types of schools in the Canton of Zürich, Switzerland. Using a two-stage procedure, parents were asked to respond to a standardized behaviour problem checklist in the screening phase. In the second stage, structured interviews were performed with 399 parents representing both screen positive and control children. DSM-III-R diagnoses were derived from the interviews. The total prevalence figure for any disorder amounted to 22.5%. Prevalence rates were influenced by the multi-screen procedure. Among various correlates, sex, nationality, age and residence were to some extent significant. Comorbid disorders were present in 12.5% of the subjects.

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