Sustainable valorisation of organic urban wastes : insights from African case studies

Understanding the problems and potentials of the organic waste stream is perhaps the single most important step that city authorities in Africa could take in moving towards sustainable, affordable, effective and efficient waste management. This publication presents four examples of recent attempts to manage organic waste sustainably in the African context. The participants in the ‘Nairobi organic urban waste’ project have structured this case exercise in order to use the case studies as object lessons, to harvest genuine insights into the feasibility of a variety of ways to successfully and sustainably valorise urban organic waste streams. Three contemporary case examples of compost production are presented. These include composting by a community-based organisation in the Kenyan private sector and by a public-private partnership in Malawi. In all three cases, the project and case study focus is on the relations between city waste and the agricultural supply chain. A fourth case study describes the technical and economic potential to produce and use biogas from urban organic waste

Locally responsive intervention to improve municipal solid waste collection coverage in Accra, Ghana

The paper reports on a process that engaged stakeholders to assess the strengths and weaknesses of the city of Accra’s approach to raising solid waste collection coverage. Stakeholders, working with researchers, have made the evaluation using a combination of benchmark indicators, analysis of franchise agreements, process flow diagramming of collection trends, and statistical analysis of user answers to a survey. Informal services are growing while formal services are shrinking. A logistic regression model suggests that regular collection and affordable user charges significantly increases the levels of user satisfaction. The use of a participatory approach has led to an unusual alliance: formal service providers have agreed to work with informal providers as subcontractors and support them to formalize and increase collection coverage. The positive experience of participation leads the authors to advocate institutionalizing the use of a participatory approach through stakeholder platforms to evaluate interventions and develop plans for service improvement

Amenability of algebras of approximable operators

We give a necessary and sufficient condition for amenability of the Banach algebra of approximable operators on a Banach space. We further investigate the relationship between amenability of this algebra and factorization of operators, strengthening known results and developing new techniques to determine whether or not a given Banach space carries an amenable algebra of approximable operators. Using these techniques, we are able to show, among other things, the non-amenability of the algebra of approximable operators on Tsirelson's space.Comment: 20 pages, to appear in Israel Journal of Mathematic

Bone marrow-derived endothelial progenitor cells are a major determinant of nascent tumor neovascularization

Tumors build vessels by cooption of pre-existing vasculature and de novo recruitment of bone marrow (BM)-derived endothelial progenitor cells (EPCs). However, the contribution and the functional role of EPCs in tumor neoangiogenesis are controversial. Therefore, by using genetically marked BM progenitor cells, we demonstrate the precise spatial and temporal contribution of EPCs to the neovascularization of three transplanted and one spontaneous breast tumor in vivo using high-resolution microscopy and flow cytometry. We show that early tumors recruit BM-derived EPCs that differentiate into mature BM-derived endothelial cells (ECs) and luminally incorporate into a subset of sprouting tumor neovessels. Notably, in later tumors, these BM-derived vessels are diluted with non-BM-derived vessels from the periphery, which accounts for purported differences in previously published reports. Furthermore, we show that specific ablation of BM-derived EPCs with alpha-particle-emitting anti-VE-cadherin antibody markedly impaired tumor growth associated with reduced vascularization. Our results demonstrate that BM-derived EPCs are critical components of the earliest phases of tumor neoangiogenesis

A global catalog of primary reptile type specimens

We present information on primary type specimens for 13,282 species and subspecies of reptiles compiled in the Reptile Database, that is, holotypes, neotypes, lectotypes, and syntypes. These represent 99.4% of all 13,361 currently recognized taxa (11,050 species and 2311 subspecies). Type specimens of 653 taxa (4.9%) are either lost or not located, were never designated, or we did not find any information about them. 51 species are based on iconotypes. To map all types to physical GLOBAL TYPE CATALOG OF REPTILES Zootaxa 4695 (5) © 2019 Magnolia Press · 439collections we have consolidated all synonymous and ambiguous collection acronyms into an unambiguous list of 364 collections holding these primary types. The 10 largest collections possess more than 50% of all (primary) reptile types, the 36 largest collections possess more than 10,000 types and the largest 73 collections possess over 90% of all types. Of the 364 collections, 107 hold type specimens of only 1 species or subspecies. Dozens of types are still in private collections. In order to increase their utility, we recommend that the description of type specimens be supplemented with data from high-resolution images and CT-scans, and clear links to tissue samples and DNA sequence data (when available). We request members of the herpetological community provide us with any missing type information to complete the list.Copyright © 2019 Magnolia Press. This is an open access article .icensed under a Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0. The attached file is the published pdf.NHM Repositor

How university’s activities support the development of students’ entrepreneurial abilities: case of Slovenia and Croatia

The paper reports how the offered university activities support the development of students’ entrepreneurship abilities. Data were collected from 306 students from Slovenian and 609 students from Croatian universities. The study reduces the gap between theoretical researches about the academic entrepreneurship education and individual empirical studies about the student’s estimation of the offered academic activities for development of their entrepreneurial abilities. The empirical research revealed differences in Slovenian and Croatian students’ perception about (a) needed academic activities and (b) significance of the offered university activities, for the development of their entrepreneurial abilities. Additionally, the results reveal that the impact of students’ gender and study level on their perception about the importance of the offered academic activities is not significant for most of the considered activities. The main practical implication is focused on further improvement of universities’ entrepreneurship education programs through selection and utilization of activities which can fill in the recognized gaps between the students’ needed and the offered academic activities for the development of students’ entrepreneurial abilities

PET Imaging of Soluble Yttrium-86-Labeled Carbon Nanotubes in Mice

The potential medical applications of nanomaterials are shaping the landscape of the nanobiotechnology field and driving it forward. A key factor in determining the suitability of these nanomaterials must be how they interface with biological systems. Single walled carbon nanotubes (CNT) are being investigated as platforms for the delivery of biological, radiological, and chemical payloads to target tissues. CNT are mechanically robust graphene cylinders comprised of sp(2)-bonded carbon atoms and possessing highly regular structures with defined periodicity. CNT exhibit unique mechanochemical properties that can be exploited for the development of novel drug delivery platforms. In order to evaluate the potential usefulness of this CNT scaffold, we undertook an imaging study to determine the tissue biodistribution and pharmacokinetics of prototypical DOTA-functionalized CNT labeled with yttrium-86 and indium-111 ((86)Y-CNT and (111)In-CNT, respectively) in a mouse model.The (86)Y-CNT construct was synthesized from amine-functionalized, water-soluble CNT by covalently attaching multiple copies of DOTA chelates and then radiolabeling with the positron-emitting metal-ion, yttrium-86. A gamma-emitting (111)In-CNT construct was similarly prepared and purified. The constructs were characterized spectroscopically, microscopically, and chromatographically. The whole-body distribution and clearance of yttrium-86 was characterized at 3 and 24 hours post-injection using positron emission tomography (PET). The yttrium-86 cleared the blood within 3 hours and distributed predominantly to the kidneys, liver, spleen and bone. Although the activity that accumulated in the kidney cleared with time, the whole-body clearance was slow. Differential uptake in these target tissues was observed following intravenous or intraperitoneal injection.The whole-body PET images indicated that the major sites of accumulation of activity resulting from the administration of (86)Y-CNT were the kidney, liver, spleen, and to a much less extent the bone. Blood clearance was rapid and could be beneficial in the use of short-lived radionuclides in diagnostic applications