Guidelines for the Integrated Management of Mountain Ecosystems

The United Nations Conference of Environment and Development in Rio de Janeiro (1992), the Earth Summit, appropriately recognized the mountains as one of the most threatened ecosystems on the planet. Recent research has shown that this threat may increase significantly in the future as a result of the greenhouse effect. At Rio the nations of the world agreed to a mountain agenda for the 21st century. But although the principles are clear enough there are very few practical guides on how actually to implement Agenda 21 especially at the grass roots. This small publication is a first attempt to spell out the first steps in doing something about the crisis in the mountains. What follows is derived from a joint project in the 1980s involving UNEP, the USSR State Committee for Environmental Protection, Centre for International Projects, the Bulgarian Ministry of Agriculture and Food Industry, Academy of Agriculture, the Poushkarov Institute of Soil Science and Agroecology, and the Georgian Agricultural Academy of Sciences. The objectives of the project were to create an international network of experts, both distinguished scientists and representatives of the leading international organizations who would direct field experiments and consider alternative methods for the complex integrated management of mountain ecosystems. The experimental plots were in the Caucasus, the Rhodopes, and Balkan mountains, including a range of mountain situations -- mediterranean, subtropical, high mountains, etc. To these sites were brought students mainly from developing countries, to learn at first hand the practical details of environmental protection in the mountains. From these courses guidelines were produced which form the basis for this publication. There were many other by-products of great use -- films, advisory missions to the Himalayas and Africa, classifications of soils and productivity, technical reports on a range of topics including landslides, mechanization, and agroecology. The project was evaluated as a success story and most appreciated by the students who greatly enjoyed the summer journeys into the idyllic Georgian and Bulgarian mountains. Whatever happens to the project in these more wintry times, the networks forged in those remote valleys will endure. Indeed the project brought together from such regions as the Andes experts and students who never met at home but who now cooperate actively

Surface enhanced Raman scattering of crystal violet

Despite the ubiquity of Raman spectroscopy, fluorescence, poor signal strength and photobleaching pose a significant challenge to researchers in the biomedical field. Here, we demonstrate a 17-fold signal enhancement in Raman spectra of crystal violet via surface-enhanced Raman scattering (SERS). The SERS substrate was fabricated by electron beam lithography (EBL); the nanostructured surface was an array of G-shaped elements made of Au on SiO2/Si. In addition to the SERS spectra, finite-difference time-domain simulations were performed to illustrate the distribution of electric-field hot-spots on the SERS substrate. The electric-field hot-spots were prominent at the vertices and edges of the nanostructured G-shaped motifs. The results presented here demonstrate that EBL is a high-end choice for SERS substrate fabrication that opens the way for more complex Raman spectroscopies, for instance involving nonlinear optics or chiral analytes

Magnetoplasmonic design rules for active magneto-optics

Light polarization rotators and non-reciprocal optical isolators are essential building blocks in photonics technology. These macroscopic passive devices are commonly based on magneto-optical Faraday and Kerr polarization rotation. Magnetoplasmonics - the combination of magnetism and plasmonics - is a promising route to bring these devices to the nanoscale. We introduce design rules for highly tunable active magnetoplasmonic elements in which we can tailor the amplitude and sign of the Kerr response over a broad spectral range

Degradation of chlorophyll and synthesis of flavonols during autumn senescence-the story told by individual leaves

Autumn senescence of deciduous trees is characterized by chlorophyll degradation and flavonoid synthesis. In the present study, chlorophyll and flavonol contents were measured every morning and evening during the whole autumn with a non-destructive method from individual leaves of Sorbus aucuparia, Acer platanoides, Betula pendula and Prunus padus. In most of the studied trees, the chlorophyll content of each individual leaf remained constant until a phase of rapid degradation commenced. The fast phase lasted only similar to 1 week and ended with abscission. In S. aucuparia, contrary to the other species, the chlorophyll content of leaflets slowly but steadily decreased during the whole autumn, but rapid chlorophyll degradation commenced only prior to leaflet abscission also in this species. An increase in flavonols commonly accompanied the rapid degradation of chlorophyll. The results may suggest that each individual tree leaf retains its photosynthetic activity, reflected by a high chlorophyll content, until a rapid phase of chlorophyll degradation and flavonoid synthesis begins. Therefore, in studies of autumn senescence, leaves whose chlorophyll content is decreasing and leaves with summertime chlorophyll content (i.e. the leaves that have not yet started to degrade chlorophyll) should be treated separately

Nonlinear superchiral meta-surfaces: tuning chirality and disentangling non-reciprocity at the nanoscale.

Circularly polarized light is incident on a nanostructured chiral meta-surface. In the nanostructured unit cells whose chirality matches that of light, superchiral light is forming and strong optical second harmonic generation can be observed

The origin of second harmonic generation hotspots in chiral optical metamaterials [Invited]

Novel ways to detect the handedness in chiral optical metamaterials by means of the second harmonic generation (SHG) process have recently been proposed. However, the precise origin of the SHG emission has yet to be unambiguously established. In this paper, we present computational simulations of both the electric currents and the electromagnetic fields in chiral planar metamaterials, at the fundamental frequency (FF), and discuss the implications of our results on the characteristics of experimentally measured SHG. In particular, we show that the results of our numerical simulations are in good agreement with the experimental mapping of SHG sources. Thus, the SHG in these metamaterials can be attributed to a strong local enhancement of the electromagnetic fields at the FF, which depends on the particular structure of the patterned metamaterial

Women and Illegal Activities: Gender Differences and Women's Willingness to Comply Over Time

In recent years the topics of illegal activities such as corruption or tax evasion have attracted a great deal of attention. However, there is still a lack of substantial empirical evidence about the determinants of compliance. The aim of this paper is to investigate empirically whether women are more willing to be compliant than men and whether we observe (among women and in general) differences in attitudes among similar age groups in different time periods (cohort effect) or changing attitudes of the same cohorts over time (age effect) using data from eight Western European countries from the World Values Survey and the European Values Survey that span the period from 1981 to 1999. The results reveal higher willingness to comply among women and an age rather than a cohort effect. Working Paper 06-5

Enantiomorphing Chiral Plasmonic Nanostructures:A Counterintuitive Sign Reversal of the Nonlinear Circular Dichroism

Plasmonic nanostructures have demonstrated a remarkable ability to control light in ways never observed in nature, as the optical response is closely linked to their flexible geometric design. Due to lack of mirror symmetry, chiral nanostructures allow twisted electric field “hotspots” to form at the material surface. These hotspots depend strongly on the optical wavelength and nanostructure geometry. Understanding the properties of these chiral hotspots is crucial for their applications; for instance, in enhancing the optical interactions with chiral molecules. Here, the results of an elegant experiment are presented: by designing 35 intermediate geometries, the structure is “enantiomorphed” from one handedness to the other, passing through an achiral geometry. Nonlinear multiphoton microscopy is used to demonstrate a new kind of double‐bisignate circular dichroism due to enantiomorphing, rather than wavelength change. From group theory, a fundamental origin of this plasmonic chiroptical response is proposed. The analysis allows the optimization of plasmonic chiroptical materials

Designer Magnetoplasmonics with Nickel Nanoferromagnets

We introduce a new perspective on magnetoplasmonics in nickel nanoferromagnets by exploiting the phase tunability of the optical polarizability due to localized surface plasmons and simultaneous magneto-optical activity. We demonstrate how the concerted action of nanoplasmonics and magnetization can manipulate the sign of rotation of the reflected light’s polarization (i.e., to produce Kerr rotation reversal) in ferromagnetic nanomaterials and, further, how this effect can be dynamically controlled and employed to devise conceptually new schemes for biochemosensing. © 2011 American Chemical Society.A.D. and Z.P. acknowledge support from the Swedish Research Council and Swedish Foundation for Strategic Research (Framework program Functional Electromagnetic Metamaterials, project RMA08). J.Å. acknowledges support from the Swedish Research Council, the Swedish Foundation for Strategic Research (Future Research Leader Programme), and the G€oran Gustafsson Foundation. J.Å. is a Royal Swedish Academy of Sciences Research Fellow supported by a grant from the Knut and Alice Wallenberg Foundation. V.B. acknowledges the G€oran Gustafsson Foundation and the Blanceflor Boncompagni-Ludovisi Foundation. P.V. acknowledges funding from the Basque Government through the ETORGAI Program, Project No. ER- 2010/00032 and Program No. PI2009-17, the Spanish Ministry of Science and Education under Projects No. CSD2006-53 and No. MAT2009-07980. J.N. acknowledges funding for the Generalitat de Catalunya and the Spanish Ministry of Science and Education through No. 2009-SGR-1292 and No. MAT2010-20616-C02 projects.Peer Reviewe