9 research outputs found
Trajectory-Aware Rate Adaptation for Flying Networks
Despite the trend towards ubiquitous wireless connectivity, there are
scenarios where the communications infrastructure is damaged and wireless
coverage is insufficient or does not exist, such as in natural disasters and
temporary crowded events. Flying networks, composed of Unmanned Aerial Vehicles
(UAV), have emerged as a flexible and cost-effective solution to provide
on-demand wireless connectivity in these scenarios. UAVs have the capability to
operate virtually everywhere, and the growing payload capacity makes them
suitable platforms to carry wireless communications hardware. The state of the
art in the field of flying networks is mainly focused on the optimal
positioning of the flying nodes, while the wireless link parameters are
configured with default values. On the other hand, current link adaptation
algorithms are mainly targeting fixed or low mobility scenarios.
We propose a novel rate adaptation approach for flying networks, named
Trajectory Aware Rate Adaptation (TARA), which leverages the knowledge of
flying nodes' movement to predict future channel conditions and perform rate
adaptation accordingly. Simulation results of 100 different trajectories show
that our solution increases throughput by up to 53% and achieves an average
improvement of 14%, when compared with conventional rate adaptation algorithms
such as Minstrel-HT
peouenosfrutos 17 pós-colheita Conservação de Morangos com utilização de Óleos Essenciais
Nos últimos anos, a
cultura do morango tem
vindo a assumir uma maior
importância devido ao seu
potencial de exportação e
à elevada procura que se
verifica, mas a sua curta
vida útil dificulta a sua
comercialização
Oral cleft prevention program (OCPP)
Abstract Background Oral clefts are one of the most common birth defects with significant medical, psychosocial, and economic ramifications. Oral clefts have a complex etiology with genetic and environmental risk factors. There are suggestive results for decreased risks of cleft occurrence and recurrence with folic acid supplements taken at preconception and during pregnancy with a stronger evidence for higher than lower doses in preventing recurrence. Yet previous studies have suffered from considerable design limitations particularly non-randomization into treatment. There is also well-documented effectiveness for folic acid in preventing neural tube defect occurrence at 0.4 mg and recurrence with 4 mg. Given the substantial burden of clefting on the individual and the family and the supportive data for the effectiveness of folic acid supplementation as well as its low cost, a randomized clinical trial of the effectiveness of high versus low dose folic acid for prevention of cleft recurrence is warranted. Methods/design This study will assess the effect of 4 mg and 0.4 mg doses of folic acid, taken on a daily basis during preconception and up to 3 months of pregnancy by women who are at risk of having a child with nonsyndromic cleft lip with/without palate (NSCL/P), on the recurrence of NSCL/P. The total sample will include about 6,000 women (that either have NSCL/P or that have at least one child with NSCL/P) randomly assigned to the 4 mg and the 0.4 mg folic acid study groups. The study will also compare the recurrence rates of NSCL/P in the total sample of subjects, as well as the two study groups (4mg, 0.4 mg) to that of a historical control group. The study has been approved by IRBs (ethics committees) of all involved sites. Results will be disseminated through publications and presentations at scientific meetings. Discussion The costs related to oral clefts are high, including long term psychological and socio-economic effects. This study provides an opportunity for huge savings in not only money but the overall quality of life. This may help establish more specific clinical guidelines for oral cleft prevention so that the intervention can be better tailored for at-risk women. ClinicalTrials.gov Identifier NCT0039791
Using active testing and meta-level information for selection of classification algorithms
The problem of selecting the best classification algorithm for a specific problem continues to be very relevant, especially since the number of classification algorithms keeps growing significantly. Testing all alternatives is not really a viable option: if we compare all pairs of algorithms, as is often advocated, the number of comparisons grows exponentially. To avoid this problem we suggest a method referred to as active testing, whose aim is to reduce the number of comparisons by carefully selecting which tests should be carried out. This method uses meta-knowledge concerning past experiments and proceeds in an iterative manner. It takes the form of a competition in which, in each iteration, the candidate best algorithm is pitted against its most promising competitor. The winner proceeds to the next round, while the loser is removed from consideration. To speed up the process of testing each pair of competitors on new datasets, we use a fast method that exploits meta-information on partial learning curves measured on prior datasets to predict which algorithm is better. We stop when there are no more viable competitors. This method was evaluated in a leave-one-out fashion, and results show that it is indeed effective in determining the best algorithm using a limited number of tests.nrpages: 8status: publishe
Oral cleft prevention program (OCPP)
Background: Oral clefts are one of the most common birth defects with significant medical, psychosocial, and economic ramifications. Oral clefts have a complex etiology with genetic and environmental risk factors. There are suggestive results for decreased risks of cleft occurrence and recurrence with folic acid supplements taken at preconception and during pregnancy with a stronger evidence for higher than lower doses in preventing recurrence. Yet previous studies have suffered from considerable design limitations particularly non-randomization into treatment. There is also well-documented effectiveness for folic acid in preventing neural tube defect occurrence at 0.4 mg and recurrence with 4 mg. Given the substantial burden of clefting on the individual and the family and the supportive data for the effectiveness of folic acid supplementation as well as its low cost, a randomized clinical trial of the effectiveness of high versus low dose folic acid for prevention of cleft recurrence is warranted.Methods/design: This study will assess the effect of 4 mg and 0.4 mg doses of folic acid, taken on a daily basis during preconception and up to 3 months of pregnancy by women who are at risk of having a child with nonsyndromic cleft lip with/without palate (NSCL/P), on the recurrence of NSCL/P. The total sample will include about 6,000 women (that either have NSCL/P or that have at least one child with NSCL/P) randomly assigned to the 4 mg and the 0.4 mg folic acid study groups. The study will also compare the recurrence rates of NSCL/P in the total sample of subjects, as well as the two study groups (4mg, 0.4 mg) to that of a historical control group. The study has been approved by IRBs (ethics committees) of all involved sites. Results will be disseminated through publications and presentations at scientific meetings.Discussion: The costs related to oral clefts are high, including long term psychological and socio-economic effects. This study provides an opportunity for huge savings in not only money but the overall quality of life. This may help establish more specific clinical guidelines for oral cleft prevention so that the intervention can be better tailored for at-risk women
Oral cleft prevention program (OCPP)
Abstract
Background
Oral clefts are one of the most common birth defects with significant medical, psychosocial, and economic ramifications. Oral clefts have a complex etiology with genetic and environmental risk factors. There are suggestive results for decreased risks of cleft occurrence and recurrence with folic acid supplements taken at preconception and during pregnancy with a stronger evidence for higher than lower doses in preventing recurrence. Yet previous studies have suffered from considerable design limitations particularly non-randomization into treatment. There is also well-documented effectiveness for folic acid in preventing neural tube defect occurrence at 0.4 mg and recurrence with 4 mg. Given the substantial burden of clefting on the individual and the family and the supportive data for the effectiveness of folic acid supplementation as well as its low cost, a randomized clinical trial of the effectiveness of high versus low dose folic acid for prevention of cleft recurrence is warranted.
Methods/design
This study will assess the effect of 4 mg and 0.4 mg doses of folic acid, taken on a daily basis during preconception and up to 3 months of pregnancy by women who are at risk of having a child with nonsyndromic cleft lip with/without palate (NSCL/P), on the recurrence of NSCL/P. The total sample will include about 6,000 women (that either have NSCL/P or that have at least one child with NSCL/P) randomly assigned to the 4 mg and the 0.4 mg folic acid study groups. The study will also compare the recurrence rates of NSCL/P in the total sample of subjects, as well as the two study groups (4mg, 0.4 mg) to that of a historical control group.
The study has been approved by IRBs (ethics committees) of all involved sites. Results will be disseminated through publications and presentations at scientific meetings.
Discussion
The costs related to oral clefts are high, including long term psychological and socio-economic effects. This study provides an opportunity for huge savings in not only money but the overall quality of life. This may help establish more specific clinical guidelines for oral cleft prevention so that the intervention can be better tailored for at-risk women.
ClinicalTrials.gov Identifier
NCT0039791
Biologists ignore ocean weather at their peril
3 pagesEcologists must understand how marine life responds to changing local conditions, rather than to overall global temperature rise, say Amanda E. Bates and 16 colleagues.
The ocean can turn on a dime. Temperature, pH, oxygen levels and salinity can vary drastically - across distances of centimetres and within time frames of minutes1-3. That’s the latest view being revealed by measurements from thousands of instruments anchored to shores or attached to floats, ocean gliders and ships. [...]Peer Reviewe
Iodine status and iodised salt consumption in portuguese school-aged children: The iogeneration study
The World Health Organization promotes salt iodisation to control iodine deficiency. In Portugal, the use of iodised salt in school canteens has been mandatory since 2013. The present study aimed to evaluate iodine status in school-aged children (6–12 years) and to monitor the use of iodised salt in school canteens. A total of 2018 participants were randomly selected to participate in a cross-sectional survey in northern Portugal. Children’s urine and salt samples from households and school canteens were collected. A lifestyle questionnaire was completed by parents to assess children’s eating frequency of iodine food sources. Urinary iodine concentration (UIC) was measured by inductively coupled plasma-mass spectrometry. The median UIC was 129 µg/L which indicates the adequacy of iodine status and 32% of the children had UIC < 100 µg/L. No school canteen implemented the iodised salt policy and only 2% of the households were using iodised salt. Lower consumption of milk, but not fish, was associated with a higher risk of iodine deficiency. Estimation of sodium intake from spot urine samples could be an opportunity for adequate monitoring of population means. Implementation of iodine deficiency control policies should include a monitoring program aligned with the commitment of reducing the population salt intake