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"Ecological intelligence" hypotheses posit that animal learning and memory evolve to meet the demands posed by foraging and, together with social intelligence and cognitive buffer hypotheses, provide a key framework for understanding cognitive evolution.1-5 However, identifying the critical environments where cognitive investment reaps significant benefits has proved challenging.6-8 Here, we capitalize upon seasonal variation in forage availability for a social insect model (Bombus terrestris audax) to establish how the benefits of short-term memory, assayed using a radial arm maze (RAM), vary with resource availability. Following a staggered design over 2 years, whereby bees from standardized colonies at identical life-history stages underwent cognitive testing before foraging in the wild, we found that RAM performance predicts foraging efficiency-a key determinant of colony fitness-in plentiful spring foraging conditions but that this relationship is reversed during the summer floral dearth. Our results suggest that the selection for enhanced cognitive abilities is unlikely to be limited to harsh environments where food is hard to find or extract,5,9-11 highlighting instead that the challenges of rich and plentiful environments, which present multiple options in short succession, could be a broad driver in the evolution of certain cognitive traits. VIDEO ABSTRACT.
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Conducta Alimentaria , Aprendizaje , Animales , Abejas , Memoria a Corto Plazo , Extractos Vegetales , Estaciones del AñoRESUMEN
Expectations for safer and sustainable chemicals and products are growing to comply with the United Nations and European strategies for sustainability. The application of Safe(r) by Design (SbD) in nanotechnology implies an iterative process where functionality, human health and safety, environmental and economic impact and cost are assessed and balanced as early as possible in the innovation process and updated at each step. The EU H2020 NanoReg2 project was the first European project to implement SbD in six companies handling and/or manufacturing nanomaterials (NMs) and nano-enabled products (NEP). The results from this experience have been used to develop these guidelines on the practical application of SbD. The SbD approach foresees the identification, estimation, and reduction of human and environmental risks as early as possible in the development of a NM or NEP, and it is based on three pillars: (i) safer NMs and NEP; (ii) safer use and end of life and (iii) safer industrial production. The presented guidelines include a set of information and tools that will help deciding at each step of the innovation process whether to continue, apply SbD measures or carry out further tests to reduce uncertainty. It does not intend to be a prescriptive protocol where all suggested steps have to be followed to achieve a SbD NM/NEP or process. Rather, the guidelines are designed to identify risks at an early state and information to be considered to identify those risks. Each company adapts the approach to its specific needs and circumstances as company decisions influence the way forward.
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Nanoestructuras , Nanotecnología , Humanos , Industrias , Nanoestructuras/efectos adversos , IncertidumbreRESUMEN
AIM: The aim of this study was to analyse the characteristics and the frequency of medical consultations in the year prior to the diagnosis and the intervention onset of the Eating Disorder, as well as the different prodromal symptoms. The final aim was to understand the origin of all referrals and their possible influence on the duration of untreated illness. METHODS: We selected 99 young patients (15-25 years) and 61 healthy controls. Their primary and specialized care medical records were both studied retrospectively. RESULTS: 87.6% of patients attended different consultations (primary care, specialized care and emergency department) the year prior compared to 67.2% of the controls (p = .002). The average number of consultations was 3.59 in the case group and 1.57 in the control group (p < .001). These consultations were related to prodromal symptoms in 57.4% compared to 16.4% for the controls (p < .001). They ranged from 29.8% of unspecific digestive symptoms, 22.8% of psychological symptoms, 19.3% of gynaecologic symptoms, 11.9% of weight variation, 8.8% of analytical changes, to 5.3% of malnutrition symptoms. Patients were mainly referred by Primary Care (42.7%). Overall, the mean of the Duration of Untreated Illness was of 7.45 months. CONCLUSIONS: The majority of reasons for consultation were related to symptoms that could be prodromal symptoms, but the patients were not diagnosed with an eating disorder. These findings highlight the importance of professionals understanding how to identify the warning signs of an eating disorder, so they can refer patients to a specialized unit to establish an early treatment.
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Trastornos de Alimentación y de la Ingestión de Alimentos , Síntomas Prodrómicos , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Servicios de Salud , Humanos , Estudios RetrospectivosRESUMEN
The synthesis and conformational analysis of a new type of conformationally restricted alpha-amino acid analogue of the amino acid antibiotic furanomycin is presented. The restriction involves the cis-fused cyclobutane and tetrahydrofuran units, generating the unusual 2-oxabicyclo[3.2.0]heptane core, which is found in a great number of biologically active natural products. The synthetic strategy is based on a formal [2 + 2] cycloaddition between 2-(acylamino)acrylates as acceptor alkenes and 2,3-dihydrofuran as a donor alkene, promoted by bulky aluminum-derived Lewis acids, particularly by methylaluminoxane (MAO). Additionally, following the same strategy, the synthesis of furanomycin analogues incorporating the 2-oxabicyclo[4.2.0]octane is reported.
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Compuestos de Aluminio/química , Aminoácidos/química , Aminoácidos/síntesis química , Ciclobutanos/síntesis química , Catálisis , Cristalografía por Rayos X , Ciclización , Ciclobutanos/química , Espectroscopía de Resonancia Magnética , Conformación Molecular , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
An extensive conformational study of different 2-substituted cyclobutane-alpha-amino acid derivatives in the solid state, in the gas phase, and in solution has been carried out. The study combines experimental techniques, such as X-ray diffraction and NMR spectroscopy, and computational methods, such as DFT calculations and molecular dynamics (MD) simulations, in a set solvent. The study reveals that the substituent at C2 in the cyclobutane ring, when fixed in an equatorial position, modulates the conformational preference of the ring-puckering.
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A formal [2 + 2] cycloaddition of 2-amidoacrylates with monosubstituted donor olefins, including its asymmetric version, is described. The stereoselectivity of this reaction can be modulated by the use of sterically hindered aluminum aryloxides or methylaluminoxane as Lewis acids. The reaction was applied to the synthesis of both stereoisomers of 2-benzyloxycyclobutane-alpha-amino acid, which are protected serine analogues c(4)Ser(OBn).