61 research outputs found
A bilateral whitish lesion on the mucosa of the cheek
An 8-year-old girl with no medical history presented
with a bilateral whitish lesion on the mucosa of the
cheek, evident since early childhood. There was no
relevant family history, and her parents had not presented
similar lesions. They reported a progressive growth of the
lesion in the last months, for which she had been evaluated
by maxillofacial surgery, the lesion being oriented as a
frictional keratosis. However, the use of occlusal splint was
not associated with any improvement. She was otherwise
asymptomatic. Physical examination revealed a bilateral,
whitish, well-demarcated cheek mucosal plaque, which
partially coincided with the dental occlusion line. The lesion
did not detach with scratching (Figure 1). No other
alterations were observed in the oral cavity or in the
systematic physical examination
Mission and system architecture for an operational network of earth observation satellite nodes
Nowadays, constellations and distributed networks of satellites are emerging as clear development trends in the space system market to enable augmentation, enhancement, and possibilities of new applications for future Earth Observation (EO) missions. While the adoption of these satellite architectures is gaining momentum for the attaining of ever more stringent application requirements and stakeholder needs, the efforts to analyze their benefits and suitability, and to assess their impact for future programmes remains as an open challenge to the EO community. In this context, this paper presents the mission and system architecture conceived during the Horizon 2020 ONION project, a European Union research activity that proposes a systematic approach to the optimization of EO space infrastructures. In particular, ONION addressed the design of complementary assets that progressively supplement current programs and took part in the exploration of needs and implementation of architectures for the Copernicus Space Component for EO. Among several use cases considered, the ONION project focused on proposing system architectures to provide improved revisit time, data latency and image resolution for a demanding application scenario of interest: Marine Weather Forecast (MWF). A set of promising system architectures has been subject of a comprehensive assessment, based on mission analysis expertise and detailed simulation for evaluating several key parameters such as revisit time and data latency of each measurement of interest, on-board memory evolution and power budget of each satellite of the constellation, ground station contacts and inter-satellite links. The architectures are built with several heterogeneous satellite nodes distributed in different orbital planes. Each platform can embark different instrument sets, which provide the required measurements for each use case. A detailed mission analysis has then been performed to the selected architecture for the MWF use case, including a refined data flow analysis to optimize system resources; a refined power budget analysis; a delta-V and a fuel budget analysis considering all the possible phases of the mission. This includes from the correction of launcher injection errors and acquisition of nominal satellite position inside the constellation, orbit maintenance to control altitude, collision avoidance to avoid collision with space debris objects and end-of-life (EOL) disposal to comply with EOL guidelines. The relevance of the system architecture selected for the MWF has been evaluated for three use cases of interest (Arctic sea-ice monitoring, maritime fishery pressure and aquaculture, agricultural hydric stress) to show the versatility and the feasibility of the chosen architecture to be adapted for other EO applications.This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 687490
3 Cat-4 mission, 1-Unit CubeSat for earth observation: Evaluation on the qualification and production during Phase D
The 3Cat-4 mission is a 1-unit CubeSat platform that serves as a technology demonstrator and educational platform for students at Universitat PolitĂšcnica de Catalunya (UPC). Promoted by the UPC Nanosatellite and Payload Laboratory (UPC NanoSatLab), the most notable subsystems that innovate in the nanosatellite scenario are (1) the Flexible Microwave Payload - 1 (FMPL-1) [1], a cost-effective payload to execute Global Navigation Satellite System Reflectometry (GNSS-R), and L-band microwave radiometry experiments using a commercial off-the-shelf (COTS) software-defined radio (SDR) and (2) the Nadir Antenna Deployment Subsystem (NADS) [2], an in-orbit deployable high-directivity antenna used by Earth Observation (EO) payloads. This paper presents the findings of the 3Cat-4 mission during Phase D, the qualification and production phase of the project. Since the publication of the first introductory work for this mission in 2019[3], several sections of the subsystems have been
redesigned and upgraded to correct previous design flaws or to meet new requirements. In addition, this paper addresses the educational perspective of this mission, analyzing its performance and usefulness in the aforementioned subject
Opposite cannabis-cognition associations in psychotic patients depending on family history
The objective of this study is to investigate cognitive performance in a first-episode psychosis sample, when stratifying the interaction by cannabis use and familial or non-familial psychosis. Hierarchical-regression models were used to analyse this association in a sample of 268 first-episode psychosis patients and 237 controls. We found that cannabis use was associated with worse working memory, regardless of family history. However, cannabis use was clearly associated with worse cognitive performance in patients with no family history of psychosis, in cognitive domains including verbal memory, executive function and global cognitive index, whereas cannabis users with a family history of psychosis performed better in these domains. The main finding of the study is that there is an interaction between cannabis use and a family history of psychosis in the areas of verbal memory, executive function and global cognition: that is, cannabis use is associated with a better performance in patients with a family history of psychosis and a worse performance in those with no family history of psychosis. In order to confirm this hypothesis, future research should explore the actual expression of the endocannabinoid system in patients with and without a family history of psychosis
Disease: A Hitherto Unexplored Constraint on the Spread of Dogs (Canis lupus familiaris) in Pre-Columbian South America
Although debate continues, there is agreement that dogs (Canis lupus familiaris) were first domesticated in Eurasia, spreading from there to other parts of the world. However, while that expansion already extended as far as Europe, China, and North America by the early Holocene, dogs spread into (and south of) the tropics only much later. In South America, for example, the earliest well attested instances of their presence do not reach back much beyond 3000 cal. BC, and dogs were still absent from large parts of the continent â Amazonia, the Gran Chaco, and much of the Southern Cone â at European contact. Previous explanations for these patterns have focused on cultural choice, the unsuitability of dogs for hunting certain kinds of tropical forest prey, and otherwise unspecified environmental hazards, while acknowledging that Neotropical lowland forests witness high rates of canine mortality. Building on previous work in Sub-Saharan Africa (Mitchell 2015) and noting that the dogâs closest relatives, the grey wolf (C. lupus) and the coyote (C. latrans), were likewise absent from South and most of Central America in Pre- Columbian times, this paper explores instead the possibility that infectious disease constrained the spread of dogs into Neotropical environments. Four diseases are considered, all likely to be native and/or endemic to South America: canine distemper, canine trypanosomiasis, canine rangeliosis, and canine visceral leishmaniasis caused by infection with Leishmania amazonensis and L. colombiensis. The paper concludes by suggesting ways in which the hypothesis that disease constrained the expansion of dogs into South America can be developed further
Acueducto pretensado sobre el arroyo de El Gato
This project is located on the main canal of the VII sector of the Bembézar (Seville) irrigated zone. It is 512.5 m long, consisting of 25 spans, each 20.50 m long. There are, in addition, two approach aqueducts, each of them 13 m in length.
The arrangement adopted was the classical one, of structural boxes, with a lower slab, and tie members between the top chords. Prestressed concrete was used, to ensure the watertightness of the canal, as well as achieving a 12% reduction in cost with respect to traditional designs in reinforced concrete.<br><br>La obra que se relata estå ubicada en el canal principal del sector VII de la zona regable del Bembézar (Sevilla). Tiene 513,5 m de longitud (25 vanos de 20,50 m), ademås de los dos acuerdos de acceso, de 13 m cada uno.
La soluciĂłn adoptada fue la clĂĄsica de cajeros resistentes con losa inferior de solera y tirantes entre las cabezas superiores, empleĂĄndose el hormigĂłn pretensado por asegurarse asĂ la impermeabilidad del conjunto, ademĂĄs de obtener una economĂa del 12 por 100 respecto a los tipos tradicionales de hormigĂłn armado
Unilateral galactocele in a 2-year-old boy: the role of GATA-3
Galactoceles are benign lesions formed at the expense of breast glandular tissue. Its occurrence in boys is exceptional, with
isolated reports in the scientifc literature. We present the case of a 2-year-old boy who debuted with a unilateral breast
enlargement of 18 months of evolution, with no other associated symptoms. Initial hormonal study showed no alterations.
Ultrasonography showed the presence of a homogeneous 5-cm retroareolar cyst. Surgical excision was indicated. During the
procedure, abundant milk drained from the lesion. The histopathological study, supported by GATA-3 immunohistochemical
staining, confrmed the diagnosis of galactocele. The range of possible diferential diagnoses for unilateral or bilateral breast
enlargement in boys is wide and includes neoplastic, vascular, and hormonal etiologies. Galactocele, which is an exceptional
entity in this group, should be considered. Immunohistochemical techniques such as GATA-3, characteristic of the breast
epithelium, can contribute to the diagnosis
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