Entanglement transition of elastic lines in a strongly disordered environment

We investigate by exact optimization the geometrical properties of three-dimensional elastic line systems with point disorder and hard-core repulsion. The line 'forests' become entangled due to increasing line wandering as the system height is increased, at fixed line density. There is a transition height at which a cluster of pairwise entangled lines spans the system, transverse to average line orientation. Numerical evidence implies that the phenomenon is in the ordinary percolation universality class.Comment: 11 pages RevTeX, eps-figs included; one figure and some references adde

Claim Preambles And The Unassailable Patent Claim, 5 J. Marshall Rev. Intell. Prop. L. 121 (2005)

In order to diminish the extensive confusion surrounding claim preambles, one must not consider what a preamble should do; rather, it is helpful to consider what a preamble should not do. Traditionally, a preamble is defined as an introduction to a statute or deed stating the document’s basis, purpose, aim, justification, and objective. However, in patents, a claim preamble does not serve this purpose. While a preamble undeniably functions as an introduction to the rest of the claim, that claim is limited in scope and therefore, so too, is the preamble. The basis, purpose, aim, justification, and objective of the invention are properly contained elsewhere in the specification, not in the claim. Indeed it is the role of the specification, not the claim preamble, to shed light on the claim terms; to describe how to make and use the invention and to disclose the best mode contemplated for its use. None of this is within the purview of the claim, or its preamble, whose purpose is solely to highlight those novel and patentable aspects of an invention. Strengthened by this knowledge, the conscientious claim drafter will realize that while a carelessly worded preamble can be a liability, a well constructed preamble can be a powerful asset

SHORT-TERM IMPACT OF AMMONIUM NITRATE AND WOOD ASH APPLICATION ON GROUND VEGETATION DIVERSITY AND SPECIES COMPOSITION IN DRAINED FORESTS

Fertilization is a way of improving tree growth and thus profitability of forestry, however this practice may cause negative side effects, such as loss of biodiversity. Ground vegetation represents a major part of plant biodiversity in forest and it is sensitive to environmental changes. The aim of the study was to characterize a short-term impact of ammonium nitrate and wood ash application on floristic composition and species diversity in conifer and deciduous forests on drained mineral and peat soils. The study was conducted in 6 stands representing Myrtillosa, Myrtillosa turf.mel., Vacciniosa mel. and Vacciniosa turf. mel. forest types. The projective cover of each species was estimated visually, separately for moss, herb and shrub layer. Shannon diversity index was calculated and compared between the plots, where fertilizers were added, and control plots. Results show that species composition corresponds to the respective forest types regardless of the application of fertilizers. In Myrtillosa mel. stands, Myrtillosa turf. mel. birch stand and Vacciniosa mel. stand nitrophilous species were more frequently observed and had a slightly larger projective cover in treatment plots, which could be explained by the impact of fertilization. Species diversity in the moss layer might have lowered as a result of fertilization, whereas no consistent patterns were observed for the herb layer. A repeated survey will show, if changes in ground vegetation persist longer

VERIFICATION OF APPLICABILITY OF FOREST GROWTH MODEL AGM IN ELABORATION OF FORESTRY PROJECTIONS FOR NATIONAL FOREST REFERENCE LEVEL

Latvia's forest reference level (FRL) should take in account the future impact of dynamic age-related forest characteristics in order to avoid unduly constraining the forest management intensity as a core element of sustainable forest management practice, with the aim of maintaining or strengthening long-term carbon sinks. The basic for calculations of GHG projections is AGM (Forest growth model) and EPIM (Emissions Projections and Inventory Model). The scope of the study is to verify applicability of the AGM model in elaboration of the forestry projections for elaboration of the FRL according to regulation (EU) 2018/841

Over a 10-year record of aerosol optical properties at SMEAR II

Aerosol optical properties (AOPs) describe the ability of aerosols to scatter and absorb radiation at different wavelengths. Since aerosol particles interact with the sun's radiation, they impact the climate. Our study focuses on the long-term trends and seasonal variations of different AOPs measured at a rural boreal forest site in northern Europe. To explain the observed variations in the AOPs, we also analyzed changes in the aerosol size distribution. AOPs of particles smaller than 10 mu m (PM10) and 1 mu m (PM1) have been measured at SMEAR II, in southern Finland, since 2006 and 2010, respectively. For PM10 particles, the median values of the scattering and absorption coefficients, single-scattering albedo, and backscatter fraction at lambda = 550 nm were 9.8 Mm(-1), 1.3 Mm(-1), 0.88, and 0.14. The median values of scattering and absorption angstrom ngstrom exponents at the wavelength ranges 450-700 and 370-950 nm were 1.88 and 0.99, respectively. We found statistically significant trends for the PM10 scattering and absorption coefficients, single-scattering albedo, and backscatter fraction, and the slopes of these trends were -0.32 Mm(-1), -0.086 Mm(-1), 2.2 x 10(-3), and 1.3 x 10(-3) per year. The tendency for the extensive AOPs to decrease correlated well with the decrease in aerosol number and volume concentrations. The tendency for the backscattering fraction and single-scattering albedo to increase indicates that the aerosol size distribution consists of fewer larger particles and that aerosols absorb less light than at the beginning of the measurements. The trends of the single-scattering albedo and backscattering fraction influenced the aerosol radiative forcing efficiency, indicating that the aerosol particles are scattering the radiation more effectively back into space.Peer reviewe

Understanding the formation of biogenic secondary organic aerosol formation from alpha-pinene in smog chamber studies: role of organic peroxy radicals

Non peer reviewe

Evaluation of greenhouse gas emissions and area of organic soils in cropland and grassland in Latvia – integrated National forest inventory data and soil maps approach

ArticleThe aim of the research was to assess distribution of organic soils in farmlands for the time period between 1990 and 2015, as well as to carry out a recalculation of GHG emissions from organic soils in grassland and cropland. We evaluated the area of typical organic soils using digitized soil maps created between 1960s and 1980s there were 183,000 ha of cropland and grassland on organic soils. A selected number of areas on organic soils intersecting with the National forest inventory (NFI) plots were surveyed. We found that 66 ± 10% of surveyed plots still conforms to criteria for organic soils according to Intergovernmental Panel on Climate Change (IPCC) guidelines; in the rest of plots soil organic matter has been mineralized and these areas do not conform to IPCC criteria of organic soils. The following distributionof organic soils was estimated in cropland – 6.3 ± 3.3% in 1990 and 4.1 ± 3.4% in 2015, but in grassland – 11.6 ± 3.6% in 1990 and 7.7 ± 3.9% in 2015. The annual reduction of GHG emissions due to reduction of area of organic soils in cropland in 2015 corresponds to 1,400,000 tonnes CO2 eq. in comparison to 1990 and in grassland – to 1,100,000 tonnes CO2 eq. The estimated reduction of the GHG emissions due to conversion of organic soils into mineral soils, comparing the average value in 2005–2009 with the projection for 2021–2030 on average will correspond to 313,000 tonnes CO2 eq. annually, however LULUCF sector still won’t become a net CO2 sink according to the GHG inventory data on other land use categories and carbon pools

Effects of different correction algorithms on absorption coefficient - a comparison of three optical absorption photometers at a boreal forest site

We present a comparison between three absorption photometers that measured the absorption coefficient (sigma(abs)) of ambient aerosol particles in 2012-2017 at SMEAR II (Station for Measuring Ecosystem-Atmosphere Relations II), a measurement station located in a boreal forest in southern Finland. The comparison included an Aethalometer (AE31), a multi-angle absorption photometer (MAAP), and a particle soot absorption photometer (PSAP). These optical instruments measured particles collected on a filter, which is a source of systematic errors, since in addition to the particles, the filter fibers also interact with light. To overcome this problem, several algorithms have been suggested to correct the AE31 and PSAP measurements. The aim of this study was to research how the different correction algorithms affected the derived optical properties. We applied the different correction algorithms to the AE31 and PSAP data and compared the results against the reference measurements conducted by the MAAP. The comparison between the MAAP and AE31 resulted in a multiple-scattering correction factor (C-ref) that is used in AE31 correction algorithms to compensate for the light scattering by filter fibers. C-ref varies between different environments, and our results are applicable to a boreal environment. We observed a clear seasonal cycle in C-ref, which was probably due to variations in aerosol optical properties, such as the backscatter fraction and single-scattering albedo, and also due to variations in the relative humidity (RH). The results showed that the filter-based absorption photometers seemed to be rather sensitive to the RH even if the RH was kept below the recommended value of 40 %. The instruments correlated well (R approximate to 0.98), but the slopes of the regression lines varied between the instruments and correction algorithms: compared to the MAAP, the AE31 underestimated sigma(abs) only slightly (the slopes varied between 0.96-1.00) and the PSAP overestimated sigma(abs) only a little (the slopes varied between 1.01-1.04 for a recommended filter transmittance >0.7). The instruments and correction algorithms had a notable influence on the absorption angstrom ngstrom exponent: the median absorption Angstrom exponent varied between 0.93-1.54 for the different algorithms and instruments.Peer reviewe

Sources and formation of nucleation mode particles in remote tropical marine atmospheres over the South China Sea and the Northwest Paci fic Ocean

Peer reviewe