404 research outputs found
Firewood and timber exploitation during the third and second millennia BC in Northwestern Iberia: wood resources, territories and chaîne opératoire
Human societies established productive strategies in order to obtain the material resources needed for their day‐to‐day life, including firewood and timber. These strategies were determined by the environmental supply, and also by the cultural characteristics and technical capacities of these communities.
This paper presents charcoal analysis data from four Chalcolithic and Bronze Age open‐air settlements located in the northwest of the Iberian Peninsula and occupied during the third and second millennia BC. These results contribute to the knowledge of the exploitation of wooden resources, of the territories where these resources were collected, and of the firewood and timber production process. The identified wood taxa point to a diversified exploitation of the territory, where firewood and timber were collected and/or felled in the deciduous woodland, the river banks and scrubland areas. The characteristics of the wood elements used, the degree of growth ring curvature, the minimum diameter of twigs or logs, etc., as well as other data from archaeological contexts, such as the length of the postholes, were all taken into account to establish hypotheses related to the operative chaine of forest resources. The wooden resources consumed in each site allowed us to hypothesize about the territory of each community.As sociedades humanas estabelecem toda uma série de estratégias produtivas destinadas a
obter os meios materiais necessários para a sua existência, entre elas, o aprovisionamento de lenha e
de madeira. Estas estratégias, além de estarem condicionadas pela oferta ambiental, são igualmente
resultantes das caraterísticas culturais e das capacidades técnicas das comunidades.
Os dados arqueobotânicos que se apresentam procedem de vários lugares de habitação do Calcolítico
e da Idade do Bronze da fachada ocidental do Noroeste peninsular com cronologias que abarcam o 3º
e parte do 2º milénios AC. Os resultados obtidos permitiram identificar uma exploração diversificada
dos recursos lenhosos que combinava a recolha de lenha e de madeira da floresta climácica com
a proveniente das áreas de mato. As formações arbóreas situadas nas margens dos cursos de água
também constituíram fonte de aprovisionamento de combustíveis e, provavelmente, de madeira.
A análise dendrológica das amostras registando o grau de curvatura dos anéis de crescimento anual, o diâmetro mínimo dos ramos ou troncos consumidos, entre outras características, em inter‑relação
com determinados contextos arqueológicos (dimensões dos buracos de poste, por exemplo),
proporcionaram hipóteses relacionadas com a cadeia técnica‑operativa
dos recursos florestais.
A caracterização dos recursos usados em cada um dos casos de estudo permitiu, igualmente, colocar
hipóteses sobre o território de vivência, de circulação e de exploração de cada comunidade.Fundação para a Ciência e Tecnologi
Optimized gene engineering of murine CAR-T cells reveals the beneficial effects of IL-15 coexpression.
Limited clinical benefit has been demonstrated for chimeric antigen receptor (CAR) therapy of solid tumors, but coengineering strategies to generate so-called fourth-generation (4G) CAR-T cells are advancing toward overcoming barriers in the tumor microenvironment (TME) for improved responses. In large part due to technical challenges, there are relatively few preclinical CAR therapy studies in immunocompetent, syngeneic tumor-bearing mice. Here, we describe optimized methods for the efficient retroviral transduction and expansion of murine T lymphocytes of a predominantly central memory T cell (TCM cell) phenotype. We present a bicistronic retroviral vector encoding both a tumor vasculature-targeted CAR and murine interleukin-15 (mIL-15), conferring enhanced effector functions, engraftment, tumor control, and TME reprogramming, including NK cell activation and reduced presence of M2 macrophages. The 4G-CAR-T cells coexpressing mIL-15 were further characterized by up-regulation of the antiapoptotic marker Bcl-2 and lower cell-surface expression of the inhibitory receptor PD-1. Overall, this work introduces robust tools for the development and evaluation of 4G-CAR-T cells in immunocompetent mice, an important step toward the acceleration of effective therapies reaching the clinic
Lattice Distortions Around a Tl+ Impurity in NaI:Tl+ and CsI:Tl+ Scintillators. An Ab Initio Study Involving Large Active Clusters
Ab initio Perturbed Ion cluster-in-the-lattice calculations of the impurity
centers NaI:Tl+ and CsI:Tl+ are pressented. We study several active clusters of
increasing complexity and show that the lattice relaxation around the Tl+
impurity implies the concerted movement of several shells of neighbors. The
results also reveal the importance of considering a set of ions that can
respond to the geometrical displacements of the inner shells by adapting
selfconsistently their wave functions. Comparison with other calculations
involving comparatively small active clusters serves to assert the significance
of our conclusions. Contact with experiment is made by calculating absorption
energies. These are in excellent agreement with the experimental data for the
most realistic active clusters considered.Comment: 7 pages plus 6 postscript figures, LaTeX. Submmited to Phys, Rev.
Important steps towards a big change for lung health: a joint approach by the European Respiratory Society, the European Society of Radiology and their partners to facilitate implementation of the European Union's new recommendations on lung cancer screening.
Enormous progress has been made on the epic journey towards implementation of lung cancer screening in Europe. A breakthrough for lung health has been achieved with the EU proposal for a Council recommendation on cancer screening. https://bit.ly/3J4O0Jb
Ab Initio Calculation of the Lattice Distortions induced by Substitutional Ag- and Cu- Impurities in Alkali Halide Crystals
An ab initio study of the doping of alkali halide crystals (AX: A = Li, Na,
K, Rb; X = F, Cl, Br, I) by ns2 anions (Ag- and Cu-) is presented. Large active
clusters with 179 ions embedded in the surrounding crystalline lattice are
considered in order to describe properly the lattice relaxation induced by the
introduction of substitutional impurities. In all the cases considered, the
lattice distortions imply the concerted movement of several shells of
neighbors. The shell displacements are smaller for the smaller anion Cu-, as
expected. The study of the family of rock-salt alkali halides (excepting CsF)
allows us to extract trends that might be useful at a predictive level in the
study of other impurity systems. Those trends are presented and discussed in
terms of simple geometric arguments.Comment: LaTeX file. 8 pages, 3 EPS pictures. New version contains
calculations of the energy of formation of the defects with model clusters of
different size
Nocturnal Hypoxemia and CT Determined Pulmonary Artery Enlargement in Smokers
Background: Pulmonary artery enlargement (PAE) detected using chest computed tomography (CT) is associated with poor outcomes in chronic obstructive pulmonary disease (COPD). It is unknown whether nocturnal hypoxemia occurring in smokers, with or without COPD, obstructive sleep apnoea (OSA) or their overlap, may be associated with PAE assessed by chest CT.
Methods: We analysed data from two prospective cohort studies that enrolled 284 smokers in lung cancer screening programs and completing baseline home sleep studies and chest CT scans. Main pulmonary artery diameter (PAD) and the ratio of the PAD to that of the aorta (PA:Ao ratio) were measured. PAE was defined as a PAD >= 29 mm in men and >= 27 mm in women or as a PA:Ao ratio > 0.9. We evaluated the association of PAE with baseline characteristics using multivariate logistic models.
Results: PAE prevalence was 27% as defined by PAD measurements and 11.6% by the PA:Ao ratio. A body mass index >= 30 kg/m(2) (OR 2.01; 95%CI 1.06-3.78), lower % predicted of forced expiratory volume in one second (FEV1) (OR 1.03; 95%CI 1.02-1.05) and higher % of sleep time with O-2 saturation < 90% (T90) (OR 1.02; 95%CI 1.00-1.03), were associated with PAE as determined by PAD. However, only T90 remained significantly associated with PAE as defined by the PA:Ao ratio (OR 1.02; 95%CI 1.01-1.03). In the subset group without OSA, only T90 remains associated with PAE, whether defined by PAD measurement (OR 1.02; 95%CI 1.01-1.03) or PA:Ao ratio (OR 1.04; 95%CI 1.01-1.07).
Conclusions: In smokers with or without COPD, nocturnal hypoxemia was associated with PAE independently of OSA coexistence
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