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Forests around the world remain under-valued because governments, policymakers, and other key actors do not consider the global or national contributions of non-timber forest products (NTFPs) when estimating the value of forests. Where available, existing estimates suggest the non-cash benefits of forests are substantial, in many cases three to ten times higher than those for which systematic national and global data are collected. Part of this under-valuation stems from a general focus by governments on forest resources that are commercially valued as well as from government failure to include estimates of NTFP contributions in their national accounts. Beyond these reasons, however, lay methodological challenges in measurement techniques and comparability across studies, countries, and regions, both of which result in limited data on NTFPs. This article reviews NTFP studies at the global and national levels to provide estimates of the non-cash contributions of NTFPs and to shed light on challenges related to the absence of systematic, reliable data on the economic contributions of forests. The article then considers the implications for forest governance, management, and policy, arguing that the Sustainable Development Goals (SDGs) offer an opportunity to increase attention on the non-cash contributions of forests and turn this invisible contribution into a visible one.

This paper presents an existence theory for solitary waves at the interface between a thin ice sheet (modelled using the Cosserat theory of hyperelastic shells) and an ideal fluid (of finite depth and in irrotational motion) for sufficiently large values of a dimensionless parameter $\gamma$. We establish the existence of a minimiser of the wave energy ${\mathcal E}$ subject to the constraint ${\mathcal I}=2\mu$, where ${\mathcal I}$ is the horizontal impulse and $0< \mu \ll 1$, and show that the solitary waves detected by our variational method converge (after an appropriate rescaling) to solutions of he nonlinear Schr\"{o}dinger equation with cubic focussing nonlinearity as $\mu \downarrow 0$., Comment: As accepted for publication

An existence and stability theory for solitary water waves with weak surface tension has recently been given by Buffoni (2005, 2009) [2,3]. The theory, which is variational in nature, relies upon the assumption that the infimum of the variational functional is strictly subhomogeneous with respect to a small parameter. In this Note we rigorously establish the relevant strict-subhomogeneity property and thus complete Buffoni's theory. (C) 2010 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

This paper presents an existence theory for small-amplitude Stokes and solitary-wave solutions to the classical water-wave problem in the absence of surface tension and with an arbitrary distribution of vorticity. The hydrodynamic problem is formulated as an infinite-dimensional Hamiltonian system in which the horizontal spatial coordinate is the time-like variable. A centre-manifold technique is used to reduce the system to a locally equivalent Hamiltonian system with one degree of freedom for values of a dimensionless parameter a near its critical value alpha*. The phase portrait of the reduced system contains a homoclinic orbit for alpha alpha*; the corresponding solutions of the water-wave problem are respectively a solitary wave of elevation and a family of Stokes waves. (c) 2008 Elsevier B.V. All rights reserved. (Less)

Starting from a Hamiltonian formulation of water waves with constant vorticity we derive several long-wave approximations. These approximate models are also Hamiltonian and the connection between the symplectic structures is described by a simple transformation theory.

Using a variational approach we prove an optimal nonlinear convolution inequality. This result is then applied to give criteria for finite-time blow-up of solutions to a nonlinear model equation in elasticity, improving considerably upon recent blow-up results.

We prove a nonoscillation result for second-order nonlinear ordinary differential equations. An application to the Schrodinger equation is also given. (C) 2004 Elsevier Ltd. All rights reserved.

In March, a new biomass-fired combined heat and power (CHP) plant was inaugurated in the Swedish city of Eskilstuna. It is one of several new projects aimed at increasing the use of biomass-fired CHP in Sweden. It is also the first commercial power plant to feature a new type of high-efficiency technology — the high-voltage generator, Powerformer™. Anders Bjorklund, Eskilstuna Energi & Miljo AB, Tord Niklasson, Swedish National Energy Administration and Mats Wahlen, ALSTOM Power Generation AB describe the biomass CHP system.

Ketonic bile acids have been found to be quantitatively important in urine of healthy infants during the neonatal period. In order to determine their structures, the bile acids in urine from 11 healthy infants were analyzed by gas-liquid chromatography-mass spectrometry (GLC-MS) and three samples with particularly high levels of ketonic bile acids were selected for detailed studies by ion exchange chromatography, fast atom bombardment mass spectrometry, microchemical reactions, and GLC-MS. The major ketonic bile acid was identified as 7 alpha, 12 alpha-dihydroxy-3-oxo-5 beta-chol-1-enoic acid, not previously described as a naturally occurring bile acid. The positional isomer 7 alpha, 12 alpha-dihydroxy-3-oxo-4-cholenoic acid, recently described as a major urinary bile acid in infants with severe liver diseases, was also excreted by most infants. Three acids related to cholic acid were identified: 7 alpha, 12 alpha-dihydroxy-3-oxo-, 3 alpha, 12 alpha-dihydroxy-7-oxo-, and 3 alpha, 7 alpha-dihydroxy-12-oxo-5 beta-cholanoic acids. Five bile acids having one oxo and three hydroxy groups were also present. Based on mass spectra and biological considerations two of these were tentatively given the structures 1 beta, 7 alpha, 12 alpha-trihydroxy-3-oxo- and 1 beta, 3 alpha, 12 alpha-trihydroxy-7-oxo-5 beta-cholanoic acids. Some of the others had a hydroxy group at C-4 or C-2. The levels of ketonic bile acids were higher on the third than on the first day of life, and lower after 1 month. The formation and excretion especially of 3-oxo bile acids is proposed to result from changes of the redox state in the liver in connection with birth.