Recombinant Listeria monocytogenes expressing a cell wall-associated listeriolysin O is weakly virulent but immunogenic

Listeriolysin O (LLO) is an essential virulence factor for the gram-positive bacterium Listeria monocytogenes. Our goal was to determine if altering the topology of LLO would alter the virulence and toxicity of L. monocytogenes in vivo. A recombinant strain was generated that expressed a surface-associated LLO (sLLO) variant secreted at 40-fold-lower levels than the wild type. In culture, the sLLO strain grew in macrophages, translocated to the cytosol, and induced cell death. However, the sLLO strain showed decreased infectivity, reduced lymphocyte apoptosis, and decreased virulence despite a normal in vitro phenotype. Thus, the topology of LLO in L. monocytogenes was a factor in the pathogenesis of the infection and points to a role of LLO secretion during in vivo infection. The sLLO strain was cleared by severe combined immunodeficient (SCID) mice. Despite the attenuation of virulence, the sLLO strain was immunogenic and capable of eliciting protec-tive T-cell responses. Listeria monocytogenes is a gram-positive facultative intra-cellular pathogen extensively used to understand host-patho-gen interactions (44, 51, 53). It expresses the highly conserved pore-forming toxin listeriolysin O (LLO), a member of a large family of cholesterol-dependent cytolysins found in many im

A holistic approach to the environmental evaluation of food waste prevention

The environmental evaluation of food waste prevention is considered a challenging task due to the globalised nature of the food supply chain and the limitations of existing evaluation tools. The most significant of these is the rebound effect: the associated environmental burdens of substitutive consumption that arises as a result of economic savings made from food waste prevention. This study introduces a holistic approach to addressing these challenges, with a focus on greenhouse gas (GHG) emissions from household food waste in the UK. It uses a hybrid life-cycle assessment model coupled with a highly detailed multi-regional environmentally extended input output analysis to capture environmental impacts across the global food supply chain. The study also takes into consideration the rebound effect, which was modelled using a linear specification of an almost ideal demand system. The study finds that food waste prevention could lead to substantial reductions in GHG emissions in the order of 706-896 kg CO$_2$-eq. per tonne of food waste, with most of these savings (78%) occurring as a result of avoided food production overseas. The rebound effect may however reduce such GHG savings by up to 60%. These findings provide a deeper insight into our understanding of the environmental impacts of food waste prevention: the study demonstrates the need to adopt a holistic approach when developing food waste prevention policies in order to mitigate the rebound effect and highlight the importance of increasing efficiency across the global food supply chain, particularly in developing countries.IDB Cambridge International Scholarship, Biotechnology and Biological Sciences Research Council (Grant ID: BB/J014540/1

Characterization of volatile compounds of cooked wild Iberian red deer meat extracted with solid phase microextraction and analysed by capillary gas chromatography - mass spectrometry

Wild Iberian red deer meat demand and interest are increasing and, therefore, an in-depth characterization of meat quality is needed to meet consumer demands. The objective of the present work was to assess, for the first time, the volatile profile of cooked wild sport-hunted Iberian red deer meat. Twenty-three loin samples from male red deer (Cervus elaphus hispanicus) were cooked and the volatile profile was analysed using solid phase microextraction, followed by capillary gas chromatography-mass spectrometry. Fifty-five volatile compounds were found. The major ones in number and relative abundance were aldehydes (84%), followed by alcohols (11%), hydrocarbons (2.4%), ketones (1.7%), furans (0.34%) and sulphur compounds (0.18%). Hexadecanal was the major compound and other long-chain compounds such as (E)-2-tetradecen-1-ol or 2-pentadecanone were also reported in considerable abundance. Several compounds related to grass-based diets were identified (2,3-octanedione, hexadecane or 1-pentadecanol). Odour impact ratio of volatile compounds was calculated and dimethyl trisulphide, (E,E)-2,4-decadienal, decanal and dodecanal were the most odorant compounds affecting the flavour of the cooked deer meat.Gobierno Vasco | Ref. IT944-16Ministerio de Economía y Competitividad | Ref. RTC-2016-5327-2Axencia Galega de Innovación | Ref. IN607A2019/01CYTED | Ref. 119RT056

Ullucus tuberosus Caldas: colección de germoplasma de ullucu conservada en el Centro Internacional de la Papa (CIP).

El presente catálogo contiene información pasaporte, datos de caracterización morfológica y ploidía para 432 accesiones de ulluco mantenidas en el banco de germoplasma del CIP. Para ilustrar mejor los datos de caracterización morfológica, cada accesión está acompañada de un set de fotografías que incluye la parte aérea de la planta, los tubérculos, las flores y una muestra lista para herborizar conformada por un tallo con sus hojas y flores. La información pasaporte es complementada con mapas ilustrados que muestran el lugar de colecta de cada accesión

Resonant Magnetic Vortices

By using the complex angular momentum method, we provide a semiclassical analysis of electron scattering by a magnetic vortex of Aharonov-Bohm-type. Regge poles of the $S$-matrix are associated with surface waves orbiting around the vortex and supported by a magnetic field discontinuity. Rapid variations of sharp characteristic shapes can be observed on scattering cross sections. They correspond to quasibound states which are Breit-Wigner-type resonances associated with surface waves and which can be considered as quantum analogues of acoustic whispering-gallery modes. Such a resonant magnetic vortex could provide a new kind of artificial atom while the semiclassical approach developed here could be profitably extended in various areas of the physics of vortices.Comment: 6 pages, 7 figure

Nexus Strength: A Novel Metric for Assessing the Global Resource Nexus

The limited access to natural resources is a major constraint for sustainability at various spatial scales. This challenge has sparked scholarly interest in the linkages or nexus between resources, with a view to helping anticipate unforeseen consequences, identify trade-offs and co-benefits, and find optimal solutions. Yet, despite decades of research, limitations in the scope and focus of studies remain. Recently constructed multiregional input-output (MRIO) databases, which cover the global economy and its use of resources in unprecedented detail, allow systematically investigation of resource use by production as well as consumption processes at various levels and garner new insights into global resource nexus (GRN) issues. This article addresses the question of how to prioritize such issues. Using the MRIO database, EXIOBASE, we address the GRN considering five key resources: blue water, primary energy, land, metal ores, and minerals. We propose a metric of nexus strength, which relies on linear goal programming to rank industries and products based on its associated combined resource use and various weighting schemes. Our results validate current research efforts by identifying water, energy, and land as the strongest linkages globally and at all scales and, at the same time, lead to novel findings into the GRN, in that (1) it appears stronger and more complex from the consumption perspective, (2) metals and minerals emerge as critical, yet undervalued, components, and (3) it manifests with a considerable diversity across countries owing to differences in the economic structure, domestic policy, technology, and resource endowments