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This article, on the Early Neolithic pottery from the Cabeço da Amoreira shellmidden in the Muge region of central Portugal, presents a detailed review of the evidence to date and a systematic analysis of the decorative and mineralogical characteristics of the stratified and radiocarbon-dated ceramic assemblage. A homogenous pottery manufacturing tradition seems to be present right from the beginning, including both local and non-local ceramics. The authors formulate a working hypothesis on the geographic origin of the exogenous pottery, which contributes to the discussion of the dynamics of mobility and social networks in the Neolithization of south-western Europe.
Litter breakdown is an important ecological process at the bottom of food webs in streams. Previous studies have been based only on a temporal interval of a single season, thus ignoring seasonal variation in litter input and community structure. We investigated organic matter input in a Brazilian savanna stream and the influence of its associated hyphomycetes on the invertebrate community. Organic matter input was sampled monthly and the leaves submitted to decomposition experiments. There were lower breakdown rates and higher invertebrate species richness and abundance during the dry season, which reached their maximum in July due to low stream discharge. Invertebrate composition was best explained by hyphomycetes (mainly by Flagellospora curvula and Anguillospora filiformis). Hyphomycetes have the capacity to degrade complex compounds of litter and to rapidly absorb nutrients by growing branched filaments, thus making the leaves more favourable for consumption by invertebrates. Shredder abundance was negatively related to litter richness, indicating possible species-specific relationships. We observed a sequential process with increased leaf litter input promoting an increase in hyphomycetes biomass, which in turn favoured invertebrate density.
Whereas the operation of forgetting has recently seen a considerable amount of attention in the context of Answer Set Programming (ASP), most of it has focused on theoretical aspects, leaving the practical issues largely untouched. Recent studies include results about what sets of properties operators should satisfy, as well as the abstract characterization of several operators and their theoretical limits. However, no concrete operators have been investigated.
In this paper, we address this issue by presenting the first concrete operator that satisfies strong persistence – a property that seems to best capture the essence of forgetting in the context of ASP – whenever this is possible, and many other important properties. The operator is syntactic, limiting the computation of the forgetting result to manipulating the rules in which the atoms to be forgotten occur, naturally yielding a forgetting result that is close to the original program.
Within the next decades, robots will need to be able to execute a large variety of tasks autonomously in a large variety of environments. To relax the resulting programming effort, a knowledge-enabled approach to robot programming can be adopted to organize information in re-usable knowledge pieces. However, for the ease of reuse, there needs to be an agreement on the meaning of terms. A common approach is to represent these terms using ontology languages that conceptualize the respective domain. In this work, we will review projects that use ontologies to support robot autonomy. We will systematically search for projects that fulfill a set of inclusion criteria and compare them with each other with respect to the scope of their ontology, what types of cognitive capabilities are supported by the use of ontologies, and which is their application domain.
This paper reports on preliminary fieldwork at the Later Stone Age site of Txina-Txina in Mozambique. Excavation yielded a long stratigraphic sequence, a large lithic assemblage, a unique decorated gastropod shell fragment and two ostrich eggshell beads—the first of their type recovered from a Stone Age context in Mozambique.
Among the myriad of desirable properties discussed in the context of forgetting in Answer Set Programming, strong persistence naturally captures its essence. Recently, it has been shown that it is not always possible to forget a set of atoms from a program while obeying this property, and a precise criterion regarding what can be forgotten has been presented, accompanied by a class of forgetting operators that return the correct result when forgetting is possible. However, it is an open question what to do when we have to forget a set of atoms, but cannot without violating this property. In this paper, we address this issue and investigate three natural alternatives to forget when forgetting without violating strong persistence is not possible, which turn out to correspond to the different possible relaxations of the characterization of strong persistence. Additionally, we discuss their preferable usage, shed light on the relation between forgetting and notions of relativized equivalence established earlier in the context of Answer Set Programming, and present a detailed study on their computational complexity.
This paper introduces a new freeware digital system, based on Google/Android platforms, designed to be a fully integrated and customizable solution to record, manage, and share archaeological survey data. The core of the system is two custom smartphone/tablet applications, through which surveyors are able to retrieve geographical coordinates and relevant attribute data from archaeological locations, but also to perform onsite analysis of artifacts, including taking accurate measurements with digital calipers directly connected to the mobile devices. The system saves all data recovered in the devices' internal memory, as well as in a cloud-based spatial database (Google Fusion Tables), where data can be automatically shared and examined using a rather intuitive set of visualization tools to instantly make maps or produce exploratory charts. Using the example of a recent field survey project for Stone Age sites in Mozambique, we provide a detailed discussion of the creation and use of all hardware and software components of our solution that will allow other researchers to reproduce the methodology and customize the system to meet the needs of their own projects.
Patient Blood Management (PBM) describes a multidisciplinary approach that strives to optimize patients own blood and has been reported to reduce blood components utilization while achieving improved patient outcomes and reduced healthcare costs. The aim of this study was to evaluate the public health and economic impact related to the implementation of a nationwide PBM program in Portugal.
A decision-model comparing two scenarios (“current clinical practice” and “with PBM implementation”) was used to estimate the PBM impact including hospital-assisted patients from the following therapeutic areas: surgery (orthopaedic, cardiac and urologic), cardiology, oncology, gastrointestinal bleeding, abnormal uterine bleeding, hemodialysis, inflammatory bowel disease and pregnancy. Model inputs were obtained from Portuguese national health databases and literature review. The public health impact was measured in life years (LY) gained, disability-adjusted life years (DALY) reduction, hospital length of stay (LOS) and 30-day readmission rate reduction. The economic value was expressed in total and hospitalization costs savings.
A total of 384,704 patients were eligible for PBM strategies. We estimated that a one year nationwide PBM implementation could avoid 594 premature deaths, representing a gain of 1,481 LY and a reduction of 3,660 DALYs relative to the current paradigm. An 8.4 percent and 37.3 percent reduction in length of stay and 30-day readmission rate are expected, respectively. This corresponds to EUR70.4 million savings in hospitalization costs. Although PBM closer monitoring would imply additional physician visits and medicines use, leading to EUR24.1 million in additional expenditure, in this population the overall PBM implementation can generate net savings of more than EUR67.7 million per year (6.3 percent reduction of public expenditure).
The implementation of a nationwide PBM in Portugal may represent a great public health impact, especially in decreased mortality and disability, with substantial public expenditure reduction.
The study of the Bom Santo Cave (central Portugal), a Neolithic cemetery, indicates a complex social, palaeoeconomic, and population scenario. With isotope, aDNA, and provenance analyses of raw materials coupled with stylistic variability of material culture items and palaeogeographical data, light is shed on the territory and social organization of a population dated to 3800–3400 cal BC, i.e. the Middle Neolithic. Results indicate an itinerant farming, segmentary society, where exogamic practices were the norm. Its lifeway may be that of the earliest megalithic builders of the region, but further research is needed to correctly evaluate the degree of this community's participation in such a phenomenon.
In this work, the correlation between the number of nonbridging oxygen (NBO) atoms and the thermal and optical properties of TeO2–Li2O–MoO3 glasses was studied. Samples containing (100 − x)TeO2–x(Li2O–MoO3) with x = 10, 15, 20, and 25 mol% were investigated by Raman and Fourier transform infrared (FTIR) spectroscopies. From the optical absorption measurements, the band gap energies were determined. The Raman and FTIR results showed that with increasing x, the TeO4 units transform into TeO3+1 units and then into TeO3 units, while the Mo coordination changes from 4 → 6. This transformation corresponds to a decrease in the total number of NBO with increasing x in this glass matrix. The decrease in the NBO is also confirmed by the increase in band gap energies and the decrease in the optical basicity, indicating a more polymerized network with increasing x.
When cognitive impairment precludes patients' report of symptoms, it becomes necessary to use other means. The purpose of our study was to evaluate the validity of the method currently in use on our service.
Two members of the team simultaneously assessed the patient and independently recorded whether the patient showed signs of discomfort, and a third questioned patients with cognitive failure who maintained some ability to respond if something was bothering them.
Some 200 assessments were made of 116 patients. The kappa coefficient of agreement was 0.615. The sensitivity was 17% and specificity 99%. The positive predictive value was 88%, and the negative predictive value was 73%.
Significance of Results:
Due to the low sensitivity of this method, it cannot be recommended as a screening tool.
Besnoitia besnoiti and Toxoplasma gondii are two closely related parasites that interact with the host cell microtubule cytoskeleton during host cell invasion. Here we studied the relationship between the ability of these parasites to invade and to recruit the host cell centrosome and the Golgi apparatus. We observed that T. gondii recruits the host cell centrosome towards the parasitophorous vacuole (PV), whereas B. besnoiti does not. Notably, both parasites recruit the host Golgi apparatus to the PV but its organization is affected in different ways. We also investigated the impact of depleting and over-expressing the host centrosomal protein TBCCD1, involved in centrosome positioning and Golgi apparatus integrity, on the ability of these parasites to invade and replicate. Toxoplasma gondii replication rate decreases in cells over-expressing TBCCD1 but not in TBCCD1-depleted cells; while for B. besnoiti no differences were found. However, B. besnoiti promotes a reorganization of the Golgi ribbon previously fragmented by TBCCD1 depletion. These results suggest that successful establishment of PVs in the host cell requires modulation of the Golgi apparatus which probably involves modifications in microtubule cytoskeleton organization and dynamics. These differences in how T. gondii and B. besnoiti interact with their host cells may indicate different evolutionary paths.
Lower limb ischaemia is the most frequent complication of cardiac catheterisation in children. It is often overlooked, but it can cause significant disability and may limit arterial access sites to repeat diagnostic or interventional catheterisations. A narrative review of the literature on arterial access site thrombosis in children was carried out with a special focus on current evidence that supports preventive and treatment strategies. Anticoagulation, thrombolysis, and thrombectomy have been used successfully to treat arterial access site thrombosis. However, it is not completely established which is the role of each treatment modality and what is the most appropriate timing to deliver it. Therefore, diagnostic and therapeutic strategies have to be prospectively investigated, particularly for clarifying the role of new pharmacologic interventions and of percutaneous and surgical thrombectomy in the current era.
Corbicula fluminea, is one of the most successful invasive species in fresh and brackish waters. Dispersal is one of the most determinant steps in the invasive process, and the full understanding of the mechanisms involved in this step is critical for adequate pest management both in the wild and in industries affected by this species’ biofouling activity. A mucous drogue line produced by mucocytes packed along the inner demibranchs of the clams’ gills seem to play an important role in assisting drifting and hence dispersal. Two Asian clam populations geographically separated (one in the USA and the other in Portugal), investigated at different times of the year, were reported to differ in terms of mucous drogue line production and floating. In this study, genetics and seasonality effects were hypothesized to explain the difference between the populations. To test these hypotheses, the two populations were genetically compared, and the Portuguese one was followed for 14 months to record the animals’ mucous drogue line production and flotation capabilities and locate the population reproductive periods. Our results signal a possible scenario of microevolution with consequences on the production of the clams’ mucilaginous drogue line. Although some authors advocate a link between mucous threads formation and reproduction events, such a relationship was not observed in this study. By contributing to the understanding of a physiological trait of the Asian clam that is important for dispersal, this study may be of practical relevance for pest monitoring and control.