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1.
Archaeobotanical material was recovered in two contiguous compartments of a compound in Monte Mozinho (Penafiel, northern Portugal). These areas comprise storage facilities from three different typologies—dolium, pits and above-ground quadrangular structures in the corner of the compartments. Few carpological materials were found inside the storage structures and all these are cereals which were most likely stored as clean grain. Recovered grains are probably remnants of the last stored crops prior to abandonment of the area. A radiocarbon date obtained on grains of rye positions this event at a time within the 3rd century and the beginning of the 4th century a.d. Outside the structures from compartment 2, abundant crop processing by-products, mostly weeds and chaff, were recovered. Since traditional agricultural communities tend not to waste such organic material, it is likely that it was kept in the area to be used as fodder. Data is ambiguous regarding the possible existence of fodder crops mixed with these by-products. Overall, there is a predominance of millets (Panicum miliaceum and Setaria italica) and rye (Secale cereale), but naked wheat (Triticum aestivum) is also a relevant crop. The presence of oat (Avena) is significant but it is difficult to interpret due to its exclusive presence alongside weeds and chaff. Grape pips (Vitis vinifera) were also found, but these are rare. The Late Roman carpological material from Monte Mozinho is of great relevance on a regional level. It documents and dates the presence of rye and testifies to a multifunctional system in which plant husbandry and animal breeding were intertwined.  相似文献   
2.
Colour modifications caused by exposure to artificial UV radiation (350 nm, UV-A) of four tropical hardwoods, jatobá, angelim vermelho, garapeira, and marupá, have been evaluated by diffuse reflectance spectroscopy and by the CIE-L*a*b* system. To obtain the absorption maxima of the chromophore species formed during UV irradiation, Kubelka-Munk (K-M) difference spectra (non-irradiated-irradiated) have been recorded as a function of exposure time. The K-M difference spectra have shown that the investigated species develop strong absorption bands in the visible region upon UV irradiation that were assigned to the formation of lignin and extractive photodegradation products. The K-M difference spectra and CIE-L*a*b* parameters ( DeltaL, Deltaa, and Deltab) have shown that marupá is the wood species that suffers the major changes upon UV irradiation while angelim vermelho was the least affected.  相似文献   
3.
A comparative study of rubber sheets obtained using formic, acetic, and smoke acid as coagulants is shown for latex obtained from native Amazonian trees and also from commercial cultivated trees. The evaluation of both processes of coagulation was carried out by spectroscopic and physical-chemical analysis, showing no differences in the rubber sheets obtained. This new method of rubber sheet preparation was introduced into Amazonian rainforest rubber tapper communities, which are actually producing in large scale. The physical-mechanical properties were similar among a large sheets made by different rubber tapper communities using this new method.  相似文献   
4.
A taxonomic reevaluation of two little-knownBrimeura taxa,B. fontqueri (Pau)Speta andB. duvigneaudii (L. Llorens)Rosselló et al., has been made.Brimeura fontqueri, described from the Iberian peninsula, has been put into synonymy ofB. amethystina (L.)Salisb., since it could not be distinguished on morphological, anatomical or cytogenetic grounds.Brimeura duvigneaudii, from the Balearic Islands, is closely related toB. amethystina and has 2n=28 chromosomes. It differs from the latter by its naked bulbs lacking dark cataphylls, and its narrower leaves and whitish corollas. Accessory chromosomes are reported for the first time in the genus. Karyological instability (with chromosome numbers ranging from 2n=28 to 42) is reported for a population ofB. fastigiata (Viv.)Chouard. A key to the recognized taxa ofBrimeura is provided.  相似文献   
5.
This paper presents a new computational framework for automatic foot classification from digital plantar pressure images. It classifies the foot as left or right and simultaneously calculates two well-known footprint indices: the Cavanagh's arch index (AI) and the modified AI. The accuracy of the framework was evaluated using a set of plantar pressure images from two common pedobarographic devices. The results were outstanding, as all feet under analysis were correctly classified as left or right and no significant differences were observed between the footprint indices calculated using the computational solution and the traditional manual method. The robustness of the proposed framework to arbitrary foot orientations and to the acquisition device was also tested and confirmed.  相似文献   
6.
Fish is a very important part of the human diet in Amazonia. Near the growing cities, fish populations and individual size have decreased over the past decades. Alternatives to traditional and industrial fishing arise, including fish farming. Strategies to minimize the impact of fish farms on the environment are needed to have a regular and healthy fish supply. This is to avoid a reduction of biodiversity, a depletion of natural resources, and/or the induction of significant changes in the structure and functioning of adjacent ecosystems. Very little research has been performed on management of effluents as to maintain the quality of water resources. The present study aimed at testing the efficiency of the Amazonian aquatic macrophyte Eichhornia crassipes as a biofilter for the treatment of effluents from fish farming. In three filtering treatments (50%, 75% and 100% plant cover) and a control (0%), physical and chemical properties of the water were measured and analyzed in a nursery with fish after passing the biofilter system, with a hydraulic retention time of 24 hours. The analyzed variables showed no significant differences (p>0.05) among the treatments with 50-100% cover, indicating that 50% cover would be enough for a good efficiency of the biofilter. All parameters were reduced after passage of the biofilter under the presence of E. crassipes: 73.7% for electrical conductivity, 15% for pH, 84.5% for turbidity, 86.8% for nitrite, 69% for total phosphorus, and 77.8% for orthophosphate. The concentrations of total nitrogen, nitrate and ammonium ions were not significantly changed (p>0.05). We conclude that E. crassipes is effective in improving the quality of effluents from fish farming, with less efficiency for nitrogen compounds. Our treatment system can be adopted by small and medium-sized farmers, aiming at a sustainable employment of the activity.  相似文献   
7.
This paper presents a new computational framework for automatic foot classification from digital plantar pressure images. It classifies the foot as left or right and simultaneously calculates two well-known footprint indices: the Cavanagh's arch index (AI) and the modified AI. The accuracy of the framework was evaluated using a set of plantar pressure images from two common pedobarographic devices. The results were outstanding, as all feet under analysis were correctly classified as left or right and no significant differences were observed between the footprint indices calculated using the computational solution and the traditional manual method. The robustness of the proposed framework to arbitrary foot orientations and to the acquisition device was also tested and confirmed.  相似文献   
8.
Abstract

After a stroke in middle cerebral artery territory, there is a high probability of dysfunction of the ventromedial pathways, mainly related with postural control mechanisms such as the anticipatory postural adjustments (APAs). According to neuroanatomical knowledge, these pathways have a predominant ipsilesional disposition, which justifies a bilateral postural control dysfunction, often neglected in rehabilitation. In order to assess this bilateral postural control dysfunction, electromyography activity was assessed in eight post-stroke and 10 healthy individuals in the anterior deltoids, the superior and lower trapezius, and the latissimus dorsi as they reached for a bottle with both upper limbs separately at a self-selected velocity and fast velocity while standing associated with trunk kinematics analysis. Through this analysis it was possible to compare the timing of APAs in scapular muscles between sides in post-stroke and with healthy individuals, and to verify if there is a relation between the timing and the displacement of the trunk in the temporal window of the APAs. Indeed, post-stroke individuals show a delayed activation of APAs on scapular girdle muscles on both ipsilesional and contralesional sides, which were not reflected in the trunk displacement.  相似文献   
9.
Most stroke lesions occur in the middle cerebral artery territory, presenting a high probability of damage of pathways with predominant ipsilesional disposition, mainly related to postural control. Despite the high probability of bilateral postural control dysfunction based on neuroanatomical fundaments, both research and clinical rehabilitation involving stroke subjects have been focused on contralesional side (also named affected side) impairments, while ipsilesional side (also named non-affected side) impairments have been attributed to an adaptive strategy. This paper aims to present a critical understanding about the state-of-the-art that sustains the hypothesis that stroke subjects with middle cerebral artery territory lesion at the subcortical level show an atypical behaviour in the ipsilateral side associated with the lesion itself and the possible implications.  相似文献   
10.
The aim of this study was to analyze the influence of position and pauses on muscle activity and fatigue during the task of ironing. Ten female participants performed the task of ironing in two different positions (standing and sitting) for 10?min each with a 1-min pause at the end of each task. Muscle activity and fatigue from the upper trapezium, anterior deltoid, and pectoralis major were analyzed using surface electromyography. The results showed that the positions had no significant influence on muscle activity; nevertheless, they had significant influence on muscular fatigue. In addition, the pauses were possibly beneficial in decreasing the muscle fatigue, but the results were not conclusive.  相似文献   
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