Helping smallholder farmers mitigate climate change

Key messages - Smallholder farmers can contribute significantly to climate change mitigation but will need incentives to adapt their practices. - Incentives from selling carbon credits are limited by low returns to farmers, high transaction costs, and the need for farmers to invest in mitigation activities long before they receive payments. - Improved food security, economic benefits and adaptation to climate change are more fundamental incentives that should accompany mitigation. - Designing agricultural investment and policy to provide up-front finance and longer term rewards for mitigation practices will help reach larger numbers of farmers than specialized mitigation interventions

Largeness and SQ-universality of cyclically presented groups

Largeness, SQ-universality, and the existence of free subgroups of rank 2 are measures of the complexity of a finitely presented group. We obtain conditions under which a cyclically presented group possesses one or more of these properties. We apply our results to a class of groups introduced by Prishchepov which contains, amongst others, the various generalizations of Fibonacci groups introduced by Campbell and Robertson

An antiproton driver for ICF propulsion

Inertial confinement fusion (ICF) utilizing an anitprotoncatalyzed target is discussed as a possible source of propulsion for rapid interplanetary manned space missions. The relevant compression, ignition, and thrust mechanisms are presented. Progress on an experiment presently in progress at the Phillips Laboratory, Kirtland AFB, NM to demonstrate proof-of-principle is reviewed

Black Hole Entropy and Finite Geometry

It is shown that the $E_{6(6)}$ symmetric entropy formula describing black holes and black strings in D=5 is intimately tied to the geometry of the generalized quadrangle GQ$(2,4)$ with automorphism group the Weyl group $W(E_6)$. The 27 charges correspond to the points and the 45 terms in the entropy formula to the lines of GQ$(2,4)$. Different truncations with $15, 11$ and 9 charges are represented by three distinguished subconfigurations of GQ$(2,4)$, well-known to finite geometers; these are the "doily" (i. e. GQ$(2,2)$) with 15, the "perp-set" of a point with 11, and the "grid" (i. e. GQ$(2,1)$) with 9 points, respectively. In order to obtain the correct signs for the terms in the entropy formula, we use a non- commutative labelling for the points of GQ$(2,4)$. For the 40 different possible truncations with 9 charges this labelling yields 120 Mermin squares -- objects well-known from studies concerning Bell-Kochen-Specker-like theorems. These results are connected to our previous ones obtained for the $E_{7(7)}$ symmetric entropy formula in D=4 by observing that the structure of GQ$(2,4)$ is linked to a particular kind of geometric hyperplane of the split Cayley hexagon of order two, featuring 27 points located on 9 pairwise disjoint lines (a distance-3-spread). We conjecture that the different possibilities of describing the D=5 entropy formula using Jordan algebras, qubits and/or qutrits correspond to employing different coordinates for an underlying non-commutative geometric structure based on GQ$(2,4)$.Comment: 17 pages, 3 figures, v2 a new paragraph added, typos correcte

Integrating Comprehensive Geriatric Assessment for people with COPD and frailty starting pulmonary rehabilitation: the Breathe Plus feasibility trial protocol.

One in five people with COPD also lives with frailty. People living with both COPD and frailty are at increased risk of poorer health and outcomes, and face challenges to completing pulmonary rehabilitation. Integrated approaches that are adapted to the additional context of frailty are required. The aim of the present study is to determine the feasibility of conducting a randomised controlled trial of an integrated Comprehensive Geriatric Assessment for people with COPD and frailty starting pulmonary rehabilitation. This is a multicentre, mixed-methods, assessor-blinded, randomised, parallel group, controlled feasibility trial ("Breathe Plus"; ISRCTN13051922). We aim to recruit 60 people aged ≥50 with both COPD and frailty referred for pulmonary rehabilitation. Participants will be randomised 1:1 to receive usual pulmonary rehabilitation, or pulmonary rehabilitation with an additional Comprehensive Geriatric Assessment. Outcomes (physical, psycho-social and service use) will be measured at baseline, 90 days and 180 days. We will also collect service and trial process data, and conduct qualitative interviews with a sub-group of participants and staff. We will undertake descriptive analysis of quantitative feasibility outcomes (recruitment, retention, missing data, blinding, contamination, fidelity), and framework analysis of qualitative feasibility outcomes (intervention acceptability and theory, outcome acceptability). Recommendations on progression to a full trial will comprise integration of quantitative and qualitative data, with input from relevant stakeholders. This study has been approved by a UK Research Ethics Committee (ref.: 19/LO/1402). This protocol describes the first study testing the feasibility of integrating a Comprehensive Geriatric Assessment alongside pulmonary rehabilitation, and testing this intervention within a mixed-methods randomised controlled trial

A Census Of Highly Symmetric Combinatorial Designs

As a consequence of the classification of the finite simple groups, it has been possible in recent years to characterize Steiner t-designs, that is t-(v,k,1) designs, mainly for t = 2, admitting groups of automorphisms with sufficiently strong symmetry properties. However, despite the finite simple group classification, for Steiner t-designs with t > 2 most of these characterizations have remained longstanding challenging problems. Especially, the determination of all flag-transitive Steiner t-designs with 2 < t < 7 is of particular interest and has been open for about 40 years (cf. [11, p. 147] and [12, p. 273], but presumably dating back to 1965). The present paper continues the author's work [20, 21, 22] of classifying all flag-transitive Steiner 3-designs and 4-designs. We give a complete classification of all flag-transitive Steiner 5-designs and prove furthermore that there are no non-trivial flag-transitive Steiner 6-designs. Both results rely on the classification of the finite 3-homogeneous permutation groups. Moreover, we survey some of the most general results on highly symmetric Steiner t-designs.Comment: 26 pages; to appear in: "Journal of Algebraic Combinatorics

An order-theoretic characterization of the Howard-Bachmann-hierarchy

In this article we provide an intrinsic characterization of the famous Howard-Bachmann ordinal in terms of a natural well-partial-ordering by showing that this ordinal can be realized as a maximal order type of a class of generalized trees with respect to a homeomorphic embeddability relation. We use our calculations to draw some conclusions about some corresponding subsystems of second order arithmetic. All these subsystems deal with versions of light-face Π₁¹-comprehension