320 research outputs found
Experiências de Cyberbullying relatadas por estudantes do ensino superior politécnico
As TIC trouxeram múltiplos benefícios mas acarretam também riscos, nomeadamente o cyberbullying, ou seja, a prática de atos agressivos, intencionais e repetidos com recurso a dispositivos eletrónicos para, por exemplo, enviar mensagens insultuosas ou criar websites que difamam e hostilizam os outros. Este estudo teve
por objetivos conhecer a frequência e os tipos de cyberbullying praticados, sofridos e observados por estudantes do ensino superior politécnico; saber se se veriicam diferenças entre géneros e cursos; identiicar as emoções associadas aos diferentes papéis no cyberbullying; identiicar os motivos invocados pelos agressores para explicar este tipo de comportamento. Para o efeito construiu-se um questionário quantitativo que foi aplicado a 170 estudantes que frequentavam várias licenciaturas de uma instituição de ensino superior politécnico de Portugal. Os resultados revelaram que 30,6% dos estudantes já tinham sido vítimas de cyberbullying e 8,2% admitiu ter praticado cyberbullying, pelo menos algumas vezes. Um dos motivos mais evocados pelos agressores para esta prática foi a vingança relativamente a episódios ocorridos anteriormente. Não se veriicaram diferenças signiicativas entre sexos mas o fenómeno era mais frequente em cursos de engenharia comparativamente aos de educação e ciências humanas. Equaciona-se a prevenção do cyberbullying a partir da utilização dos próprios meios de comunicação social para promoção da
partilha de informação sobre como utilizar as TIC de forma ética e segura, bem como através da criação de programas e plataformas envolvendo estudantes de vários níveis de ensino com vista à prevenção deste fenómeno
A global and hemispherical analysis of the Lorenz energetics based on the representative concentration pathways used in CMIP5
So far, only a few studies have evaluated the impact of greenhouse gases emissions on the global and limited area energetics. Furthermore, all of them have concentrated on the increasing of CO2. As new climate projections are now available froma number of climate models under the MPI-ESR-MR experiment, the present study analyses the global and hemispherical energetics under the increase of greenhouse gas forcings that follow Representative Concentration Pathways (RCP26, RCP45, and RCP85). The results have shown a reduction in the LEC intensity as the concentration of greenhouse gases increases, with the RCP85 scenario generating the strongest decrease. For both global and hemispherical domains, zonal kinetic energy is the only energy reservoir which increases in awarmer environment,whereas the conversion between eddy kinetic energy and zonal kinetic energy (\u1d436����������������\u1d43e����������������) is the only energy flux also experiencing an increase. Aquantitative analysis of the inner processes involved in the conversion terms shows important changes in the horizontal and vertical eddy-transport of momentum and sensible heat. In the case of \u1d436����������������\u1d43e���������������� both vertical and horizontal eddy-transports of momentum play an important role in the increase of zonal kinetic energy for the global domain.CNPq - 150356/2011-0FAPESP - 08/58101-9CLARIS LPBINCLINE/US
Comunicação pública em territórios rurais – perceções e participação dos atores globais em Avelãs de Cima
Vivemos num mundo cada vez mais globalizado e uma das consequências é a
crescente concorrência que existe entre territórios, reforçando-se a necessidade de
fazer chegar aos públicos interessados, um conjunto de atributos e diferenciações,
suficientemente atrativos e apelativos, para que estes territórios sejam “consumidos”,
não só pelo seu reconhecimento temporal, mas também pela forma como ele se
comunica.
Se até ao momento esta diferenciação era apenas explicitada numa base meramente
turística (pelos impactos económicos positivos que normalmente se conseguem), hoje
a estratégia deve seguir um plano de marketing capaz de atrair e fixar quer residentes,
excursionistas, turistas e investidores, satisfazendo-os.
Dos estudos realizados é comumente aceite que o sucesso da execução de um plano
de marketing territorial assenta num modelo participativo que promova e antecipe
necessidades e desejos dos atores globais e que valide e identifique os pontos fortes,
para ajudar a desenvolver (definir e implementar) uma estratégia sustentável, a prazo.
Então é relevante chamar ao processo estes atores (públicos e privados, residentes e
visitantes) envolvendo-os nesta identificação, comprometendo-os também nos seus
resultados.Com este artigo apresenta-se então um estudo de caso aplicado a um território rural,
na freguesia de Avelãs de Cima, tendo sido utilizada como metodologia um inquérito
por questionário a todos os atores.
Enumeram-se os fatores relevantes identificados, assim como os que não se desejam
ver aplicados, requisitos evidentes para iniciar uma nova política de comunicação
pública.
Deste trabalho já resultou uma nova abordagem pelos atores públicos locais,
destacando a perspetiva de utilização de sinergias pela integração dos recursos de
duas outras freguesias, estando em construção um projeto comum de rotas com base
nos atributos dessas localidades.-----We live in an increasingly globalized world and one of the consequences is the
increasing competition that exists between areas, reinforcing the need to reach out to
stakeholders, a set of attributes and differences sufficiently attractive and appealing,
so that these territories are "consumed ", not only by their temporal recognition, but
also for how it communicates.
If so far this differentiation was only explained in a purely tourist base (by the positive
economic impacts that usually can get), today the strategy must follow a marketing
plan able to attract and retain residents, hikers, tourists and investors.
There are studies where is commonly accepted that the successful implementation of
a territorial marketing plan based on a participatory model that promotes and
anticipate needs and desires of the global players and validate and identify the
strengths, to help develop (define and implement) one sustainable strategy in the long
term. So it is relevant to call these actors (public and private, residents and visitors)
involving them in this identification and also committing them in their results.
With this article we present a case study applied to a rural area in the parish of Avelãs
de Cima, having been used a survey methodology for all actors.
All the relevant identified factors are listed, as well as those which do not wish to see
applied, clear requirements to start a new policy of public communication.
This work has resulted in a new approach by local public actors, highlighting the
prospect of using synergies by integrating the features of two other parishes, under
construction with a common design routes based on attributes of those localities
Performance Investigations of IEEE 802.11 a54 Mbps WPA2 Laboratory Links
The increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, resulting in more reliable and efficient communications. Security is also crucially important. Laboratory measurements are presented for several performance aspects of Wi-Fi IEEE 802.11a54 Mbps WPA2 point-to-point and four node point-to-multipoint links. Our study contributes to performance evaluation of this technology under WPA2 encryption, using available equipment (HP V-M200 access points and Linksys WPC600N adapters). New results are given from TCP and UDP experiments concerning TCP throughput versus TCP packet length, jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to corresponding results for Open links. Conclusions are drawn about the comparative performance of the links.
Keywords: Wi-Fi, WLAN, IEEE 802.11a, Wireless network laboratory performance, Multi-Node WPA2 link
Performance Evaluation of IEEE 802.11 ac WPA2 Laboratory Links
The increasing importance of wireless communications, involving electronic devices, has been widely recognized. Performance is a fundamental issue, resulting in more reliable and efficient communications. Security is also crucially important. Laboratory measurements are presented about several performance aspects of Wi-Fi IEEE 802.11ac WPA2 point-to-point links. Our study contributes to performance evaluation of this technology under WPA2 encryption, using available equipment (Cisco 2702i access points and TP-Link AC1900 USB 3.0 adapters). New results are given from TCP and UDP experiments concerning TCP throughput versus TCP packet length, jitter and percentage datagram loss versus UDP datagram size. Comparisons are made to corresponding results for WPA2 802.11n. Conclusions are drawn about the comparative performance of the links.
Keywords: Wi-Fi, WLAN, IEEE 802.11ac, Wireless network laboratory performance, Point-to-Point WPA2 link
Rapid diagnostic tests for molecular surveillance of Plasmodium falciparum malaria -assessment of DNA extraction methods and field applicability
Background: The need for new malaria surveillance tools and strategies is critical, given improved global malaria control and regional elimination efforts. High quality Plasmodium falciparum DNA can reliably be extracted from malaria rapid diagnostic tests (RDTs). Together with highly sensitive molecular assays, wide scale collection of used RDTs may serve as a modern tool for improved malaria case detection and drug resistance surveillance. However, comparative studies of DNA extraction efficiency from RDTs and the field applicability are lacking. The aim of this study was to compare and evaluate different methods of DNA extraction from RDTs and to test the field applicability for the purpose of molecular epidemiological investigations. Methods: DNA was extracted from two RDT devices (Paracheck-PfW and SD Bioline Malaria Pf/Pan (R)), seeded in vitro with 10-fold dilutions of cultured 3D7 P. falciparum parasites diluted in malaria negative whole blood. The level of P. falciparum detection was determined for each extraction method and RDT device with multiple nested-PCR and real-time PCR assays. The field applicability was tested on 855 paired RDT (Paracheck-Pf) and filter paper (Whatman (R) 3MM) blood samples (734 RDT negative and 121 RDT positive samples) collected from febrile patients in Zanzibar 2010. RDT positive samples were genotyped at four key single nucleotide polymorphisms (SNPs) in pfmdr1 and pfcrt as well as for pfmdr1 copy number, all associated with anti-malarial drug resistance. Results: The P. falciparum DNA detection limit varied with RDT device and extraction method. Chelex-100 extraction performed best for all extraction matrixes. There was no statistically significant difference in PCR detection rates in DNA extracted from RDTs and filter paper field samples. Similarly there were no significant differences in the PCR success rates and genotyping outcomes for the respective SNPs in the 121 RDT positive samples. Conclusions: The results support RDTs as a valuable source of parasite DNA and provide evidence for RDT-DNA extraction for improved malaria case detection, molecular drug resistance surveillance, and RDT quality control.ACT Consortium through Bill and Melinda Gates Foundation; Swedish International Development Agency (SIDA) [SWE 2009-193]; Swedish Civil Contingencies Agency (MSB) [2010-7991]; Swedish Medical Research Council (VR) [2009-3785]; Goljes Foundationinfo:eu-repo/semantics/publishedVersio
A genotyping array for the globally invasive vector mosquito, Aedes albopictus
Background: Although whole-genome sequencing (WGS) is the preferred genotyping method for most genomic analyses, limitations are often experienced when studying genomes characterized by a high percentage of repetitive elements, high linkage, and recombination deserts. The Asian tiger mosquito (Aedes albopictus), for example, has a genome comprising up to 72% repetitive elements, and therefore we set out to develop a single-nucleotide polymorphism (SNP) chip to be more cost-effective. Aedes albopictus is an invasive species originating from Southeast Asia that has recently spread around the world and is a vector for many human diseases. Developing an accessible genotyping platform is essential in advancing biological control methods and understanding the population dynamics of this pest species, with significant implications for public health. Methods: We designed a SNP chip for Ae. albopictus (Aealbo chip) based on approximately 2.7 million SNPs identified using WGS data from 819 worldwide samples. We validated the chip using laboratory single-pair crosses, comparing technical replicates, and comparing genotypes of samples genotyped by WGS and the SNP chip. We then used the chip for a population genomic analysis of 237 samples from 28 sites in the native range to evaluate its usefulness in describing patterns of genomic variation and tracing the origins of invasions. Results: Probes on the Aealbo chip targeted 175,396 SNPs in coding and non-coding regions across all three chromosomes, with a density of 102 SNPs per 1 Mb window, and at least one SNP in each of the 17,461 protein-coding genes. Overall, 70% of the probes captured the genetic variation. Segregation analysis found that 98% of the SNPs followed expectations of single-copy Mendelian genes. Comparisons with WGS indicated that sites with genotype disagreements were mostly heterozygotes at loci with WGS read depth \u3c 20, while there was near complete agreement with WGS read depths \u3e 20, indicating that the chip more accurately detects heterozygotes than low-coverage WGS. Sample sizes did not affect the accuracy of the SNP chip genotype calls. Ancestry analyses identified four to five genetic clusters in the native range with various levels of admixture. Conclusions: The Aealbo chip is highly accurate, is concordant with genotypes from WGS with high sequence coverage, and may be more accurate than low-coverage WGS. Graphical Abstract: (Figure presented.) © The Author(s) 2024
Teste da agulha, uma forma simples, barata e valiosa no diagnóstico da deficiência de Fósforo nos bovinos
- …