Intensification and Sustainability in South African Rooibos: exploring the conditions for market-led sustainable development in a biodiversity hot spot

The Fynbos biome in the Cape region in South Africa is currently the only production location of Rooibos tea in the world. In addition, biodiversity in the Fynbos biome is very large and unique for the world. This makes Rooibos tea a unique product, the availability of which strongly depends on the dynamics in a bounded territory. Rooibos is sometimes harvested from the wild, but up to 99% of all Rooibos is cultivated. 95% of all Rooibos is produced on large farms or plantations. Such farms, which also exist for potatoes and grapes in the Fynbos biome have a large impact on the ecosystem, especially because large areas have been cleared in the past for their establishment. For instance, ‘an average of 2.7 hectares of virgin land has been cleared for farming every day in the past 15 years’, in the Northern Sandveld

The infinitesimal characters of discrete series for real spherical spaces

Let $Z=G/H$ be the homogeneous space of a real reductive group and a unimodular real spherical subgroup, and consider the regular representation of $G$ on $L^2(Z)$. It is shown that all representations of the discrete series, that is, the irreducible subrepresentations of $L^2(Z)$, have infinitesimal characters which are real and belong to a lattice. Moreover, let $K$ be a maximal compact subgroup of $G$. Then each irreducible representation of $K$ occurs in a finite set of such discrete series representations only. Similar results are obtained for the twisted discrete series, that is, the discrete components of the space of square integrable sections of a line bundle, given by a unitary character on an abelian extension of $H$.Comment: To appear in GAF

Small-scale farmers, certification schemes and private standards: Is there a business case?

Certification of agricultural products (organic certification, Fairtrade etc.) is often expected to provide a wide array of benefits for small-scale farmers. These include poverty alleviation, reduced environmental impact and food safety. This wide-ranging synthesis of 270 studies presents an analysis of the benefits – but also the costs – of such schemes. Crucially it demonstrates that the decision to invest must be based on sound economic principles. Clearly laid out and argued, the text also provides recommendations to improve the certification business case and impact on smallholders

Petits producteurs, systèmes de certification et normes privées : Le système est-il rentable?

La certification des produits agricoles (certification agriculture biologique, commerce équitable, etc.) est souvent vue comme la source d'une multitude d'avantages pour les petits exploitants. Parmi ceux-ci, on note une réduction de la pauvreté, une baisse des répercussions sur l'environnement, et la réalisation de la sécurité alimentaire. Cette vaste synthèse de 270 études présente une analyse des bénéfices, mais aussi des coûts, de tels projets de certification. Elle démontre principalement que la décision d'investir doit être basée sur de solides principes économiques. Avec une présentation et une argumentation claires, cet ouvrage fournit également des recommandations pour améliorer le secteur de la certification et ses retombées sur les petits exploitants

Ellipticity and discrete series

We explain by elementary means why the existence of a discrete series representation of a real reductive group $G$ implies the existence of a compact Cartan subgroup of $G$. The presented approach has the potential to generalize to real spherical spaces

Small-scale farmers, certification schemes and private standards: is there a business case? : costs and benefits of certification and verification systems for small-scale producers in cocoa, coffee, cotton, fruit and vegetable sectors

Certification of agricultural products is an increasingly common tool that is expected to contribute to agricultural improvement, farmer well-being, poverty alleviation, reduced environmental impact and food safety. In an increasingly competitive market, processors, manufacturers and retailers use certification to demonstrate their green and sustainable credentials and differentiate their products. In some commodity sectors, such as coffee and cocoa, products certified as sustainable are on track to reach majority market share in important producing and consuming nations. This development poses a major challenge for farmers in general, and small-scale farmers in ACP and other developing countries, in particular. This publication, commissioned by CTA, presents the findings of a study of the impact of certification on farmers in coffee, cocoa, cotton, fruit and vegetables

Vortex trapping and expulsion in thin-film YBCO strips

A scanning SQUID microscope was used to image vortex trapping as a function of the magnetic induction during cooling in thin-film YBCO strips for strip widths W from 2 to 50 um. We found that vortices were excluded from the strips when the induction Ba was below a critical induction Bc. We present a simple model for the vortex exclusion process which takes into account the vortex - antivortex pair production energy as well as the vortex Meissner and self-energies. This model predicts that the real density n of trapped vortices is given by n=(Ba-BK)/Phi0 with BK = 1.65Phi0/W^2 and Phi0 = h/2e the superconducting flux quantum. This prediction is in good agreement with our experiments on YBCO, as well as with previous experiments on thin-film strips of niobium. We also report on the positions of the trapped vortices. We found that at low densities the vortices were trapped in a single row near the centers of the strips, with the relative intervortex spacing distribution width decreasing as the vortex density increased, a sign of longitudinal ordering. The critical induction for two rows forming in the 35 um wide strip was (2.89 + 1.91-0.93)Bc, consistent with a numerical prediction

Surgical site infection after wound closure with staples versus sutures in elective knee and hip arthroplasty:a systematic review and meta-analysis

PURPOSE: This systematic review and meta-analysis aimed to study surgical site infection of wound closure using staples versus sutures in elective knee and hip arthroplasties. METHODS: A systematic literature review was performed to search for randomized controlled trials that compared surgical site infection after wound closure using staples versus sutures in elective knee and hip arthroplasties. The primary outcome was surgical site infection. The risk of bias was assessed with the Cochrane risk of bias assessment tool. The relative risk and 95% confidence interval with a random-effects model were assessed. RESULTS: Eight studies were included in this study, including 2 studies with a low risk of bias, 4 studies having ‘some concerns’, and 2 studies with high risk of bias. Significant difference was not found in the risk of SSI for patients with staples (n = 557) versus sutures (n = 573) (RR: 1.70, 95% CI: 0.94–3.08, I(2) = 16%). The results were similar after excluding the studies with a high risk of bias (RR: 1.67, 95% CI: 0.91–3.07, I(2) = 32%). Analysis of studies with low risk of bias revealed a significantly higher risk of surgical site infection in patients with staples (n = 331) compared to sutures (n = 331) (RR: 2.56, 95% CI: 1.20–5.44, I(2) = 0%). There was no difference between continuous and interrupted sutures (P > 0.05). In hip arthroplasty, stapling carried a significantly higher risk of surgical site infection than suturing (RR: 2.51, 95% CI: 1.15–5.50, I(2) = 0%), but there was no significant difference in knee arthroplasty (RR: 0.87, 95% CI: 0.33–2.25, I(2) = 22%; P > 0.05). CONCLUSIONS: Stapling might carry a higher risk of surgical site infection than suturing in elective knee and hip arthroplasties, especially in hip arthroplasty. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s42836-021-00110-7