83 research outputs found
Age-related differences in pointing accuracy in familiar and unfamiliar environments
This study aimed to investigate age-related differences in spatial mental representations of familiar and unfamiliar places. Nineteen young adults (aged 18\u201323) and 19 older adults (aged 60\u201374), all living in the same Italian town, completed a set of visuospatial measures and then pointed in the direction of familiar landmarks in their town and in the direction of landmarks in an unknown environment studied on a map. Results showed that older adults were less accurate in the visuospatial tasks and in pointing at landmarks in an unfamiliar environment, but performed as well as the young adults when pointing to familiar places. Pointing performance correlated with visuospatial tests accuracy in both familiar and unfamiliar environments, while only pointing in an unknown environment correlated with visuospatial working memory (VSWM).
The spatial representation of well-known places seems to be well preserved in older adults (just as well as in young adults), while it declines for unfamiliar environments. Spatial abilities sustain the mental representations of both familiar and unfamiliar environments, while the support of VSWM resources is only needed for the latter
Quantum encoding of dynamic directed graphs
In application domains such as routing, network analysis, scheduling, and planning, directed graphs are widely used as both formal models and core data structures for the development of efficient algorithmic solutions. In these areas, graphs are often evolving in time: for example, connection links may fail due to temporary technical issues, meaning that edges of the graph cannot be traversed for some time interval and alternative paths have to be followed. In classical computation graphs have been implemented both explicitly through adjacency matrices/lists and symbolically as ordered binary decision diagrams. Moreover, ad-hoc visit procedures have been developed to deal with dynamically evolving graphs. Quantum computation, exploiting interference and entanglement, has provided an exponential speed-up for specific problems, e.g., database search and integer factorization. In the quantum framework everything must be represented and manipulated using reversible operators. This poses a challenge when one has to deal with traversals of dynamically evolving directed graphs. Graph traversals are not intrinsically reversible because of converging paths. In the case of dynamically evolving graphs also the creation/destruction of paths comes into play against reversibility. In this paper we propose a novel high level graph representation in quantum computation supporting dynamic connectivity typical of real-world network applications. Our procedure allows to encode any multigraph into a unitary matrix. We devise algorithms for computing the encoding that are optimal in terms of time and space and we show the effectiveness of the proposal with some examples. We describe how to react to edge/node failures in constant time. Furthermore, we present two methods to perform quantum random walks taking advantage of this encoding: with and without projectors. We implement and test our encoding obtaining that the theoretical bounds for the running time are confirmed by the empirical results and providing more details on the behavior of the algorithms over graphs of different densities
Dose para indução de esterilidade para linhagens de Anastrepha fraterculus (Diptera: Tephritidae) sob hipóxia.
A forma mais eficiente de aplicação da Técnica do Inseto Estéril (TIE) consiste na liberação apenas de machos. Para isso, são necessários mecanismos que permitam a sexagem do inseto ainda na fase imatura. Recentemente, o CENA/USP importou da FAO/IAEA Agriculture and Biotechnology Laboratories, Áustria uma Genetic Sexing Strain de Anastrepha fraterculus sp.1 (Diptera: Tephritidae) denominada GSS-89. Através de radioindução de uma translocação na banda 88 do cromossomo VI, essa linhagem apresenta dimorfismo da coloração das pupas, sendo que os machos adultos emergem de pupas marrons enquanto fêmeas emergem apenas de pupas pretas. Para manter a qualidade dos insetos sem prejudicar a esterilização, a irradiação pode ser realizada sob hipóxia (baixa concentração de oxigênio). As doses esterilizantes para A. fraterculus até o momento haviam sido estabelecidas apenas sob normóxia. Assim, este estudo foi o primeiro a avaliar a dose de indução de esterilidade sob condição de hipóxia para duas linhagens de A. fraterculus, uma linhagem bissexual (Brazilian-1) e a GSS-89. Duas horas antes da irradiação, as pupas foram colocadas em recipientes selados e irradiadas quando a concentração de oxigênio era inferior a 3 %. Foram testadas 9 doses (0 (controle), 30, 40, 50, 60, 70, 80, 90 e 100 Gy). Para determinar a esterilidade para cada linhagem e a dose, quatro tipos de cruzamentos foram realizados entre as moscas irradiadas sob hipóxia e não irradiadas da linhagem bissexual. Para os machos irradiados, foram determinados o efeito das doses de radiação na viabilidade de ovos, recuperação ovo-pupa e recuperação de adultos para as duas linhagens e ambas tiveram 74 Gy como dose esterilizante, na qual a viabilidade dos ovos foi reduzida 99%. A fertilidade das fêmeas irradiadas foi afetada até mesmo em baixas doses
Acúmulo de forragem em pastagem natural palha grossa manejada em diferentes alturas.
O objetivo do trabalho foi determinar o acúmulo de forragem em pastagem natural com predomínio de Andropogon lateralis, manejada sob diferentes alturas.Claudia Cristina Gulias Gomes, editora técnica
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Postpartum women’s use of medicines and breastfeeding practices: a systematic review
The objectives of this article are to systematically review i) the extent of medicine use in postpartum women, and ii) the impact of maternal medicine use (excluding contraceptives and galactogogues) on breastfeeding outcomes (initiation and/or duration). PubMed, Medline (Ovid), Scopus (Elsevier), Cinahl (EBSCO), PsycINFO (Ovid), Embase (Ovid) and Web of Science (ISI) databases were searched to find original studies on medicine use in women after the birth. Additional studies were identified by searching Google Scholar, Wiley Online Library, Springer Link, selected journals and from the reference list of retrieved articles. Observational studies with information about postpartum women’s use of any type of medicine either for chronic or acute illnesses with or without breastfeeding information were included. The majority of relevant studies suggest that more than 50 % of postpartum women (breastfeeding or not) required at least one medicine. Due to the lack of uniform medication use reporting system and differences in study designs, settings and samples, the proportion of medicine use by postpartum women varies widely, from 34 to 100 %. Regarding the impact of postpartum women’s medicine use on breastfeeding, a few studies suggest that women’s use of certain medicines (e.g. antiepileptics, propylthiouracil, antibiotics) during lactation can reduce initiation and/ or duration of breastfeeding. These studies are limited by small sample size, and with one exception, all were conducted in Canada more than a decade ago. Large scale studies are required to establish the relationship between maternal medicine use and breastfeeding, considering type of illness, period of use and total duration of medicine use
Consumption of medicines in high-risk pregnancy: evaluation of determinants related to the use of prescription drugs and self-medication
The use of drugs during pregnancy still represents a challenge for medicine, since the majority of drugs cross the placental barrier with a potential to cause several congenital problems to the fetus, and most of them have not been clinically tested in pregnant patients. At the same time, the medicalization phenomenon, self-medication, and lack of patient information about the misuse of medicines are additional problems. Thus, the aim of this study was to evaluate the pattern of medicine consumption in high-risk pregnancies and the determinants related to this consumption pattern. In order to do so, a cross-sectional descriptive study was performed with puerperal women who had a history of high-risk pregnancy. Statistically significant associations were found between self-medication and fewer prenatal visits, and cigarette use during pregnancy and a higher number of children. According to these data, the vulnerability of this population to the risks of drug use is evident, demonstrating a gap that requires urgent interventions in health-care education
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