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1.
Eur J Appl Physiol ; 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523228

RESUMO

BACKGROUND: Drafting is a common technique to reduce the drag experienced by elite runners on races, leading to faster finish times. The tactic has been successfully used in previous marathon world records. In the 2023 Chicago Marathon, Kenyan runner Kelvin Kiptum broke the marathon record after a 2:00:35 finish. This feat is impressive considering the lack of use of drafting, despite the availability of two pacers for the majority of the race. METHODS: In this study, the drag faced by Kiptum and his pacers during the race is calculated by means of computational fluid dynamics (CFD). The performance of each runner is evaluated from an energetic standpoint, and the analysis is extended to include more efficient drafting formations. RESULTS: Running in proper formations results in drag reductions in excess of 70% for the main runner. Our results indicate that, by properly using the advantages of drafting, Kiptum could have finished the race at a staggering 1:57:34, a full three minutes better than his own record and 215 s better than the previous world record. CONCLUSION: Proper use of drafting does indeed improve the energetic performance of a runner, allowing for lower race times and potentially helping elite runners in breaking the 2-h barrier for a marathon.

2.
Morphologie ; 108(360): 100727, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37977085

RESUMO

The discipline of anatomy is one of the pillars of training in higher education courses in health area. Since its origin, this discipline has used the traditional method as an educational strategy. Since then, the discipline has undergone changes, including other teaching methods, such as active methodologies. With the COVID-19 pandemic, declared in March 2020 and the closure of higher education institutions, the teaching of anatomy was impacted, since it was necessary to adapt the modality of face-to-face teaching to remote teaching. The present study aims to evaluate the perception of teachers regarding students' anatomy learning in relation to the types of methodologies applied in remote teaching during the pandemic. For such, a cross-sectional study was carried out, which analyzed the answers of 101 anatomy teachers. The results showed that there was no statistically significant difference regarding teachers' perception of learning in relation to the type of methodology used in remote teaching during the pandemic. There was also no difference in comparing perceptions regarding the type of methodology used before and during the pandemic. Given this, these data encourage the need for reflection in the academic community and new studies with educators and students, in order to identify factors that may improve the quality of anatomy learning.


Assuntos
COVID-19 , Pandemias , Humanos , Estudos Transversais , Aprendizagem , Percepção
3.
Arch Microbiol ; 205(3): 90, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36780035

RESUMO

The Kyzyl-Kum Desert extends over an area of 300,000 Km2, in the region bordering Kazakhstan, Uzbekistan and Turkmenistan and is mainly covered by sand dunes. The Kyzyl-Kum desert is also known for its large deposits of minerals of economic interests, the exploitation of which is affecting the local ecosystem and increasing the desertification. We examined the bacterial biodiversity of surface sand samples from several sites from the Kyzyl-Kum desert using pyrosequencing of PCR amplified bacterial 16S rRNA genes from total extracted soil DNA. We also examined several physicochemical parameters of the sand samples to investigate any possible correlations between bacterial community structure and environmental drivers. The predominant bacterial phyla present in the samples were found to belong to members of the Actinobacteria, Proteobacteria and Bacteroidetes. The most abundant genera in our samples were found to belong to the Arthrobacter, Adhaeribacter and Roseomonas genera. We found that the relative abundance of members belonging to the Actinobacteria phylum, commonly found in desertic areas, increase in abundance in sites with higher content of organic matter and sulfur, whereas members of the Proteobacteria and Bacteroidetes phyla seems to diminish in abundance in coarse silt and fine-grained soils and those rich in magnesium, suggesting that those parameters might influence the bacterial community composition in this desertic area. This study is the first to provide new insights into the prokaryotic community composition from this unusual desert site.


Assuntos
Microbiota , Areia , Uzbequistão , RNA Ribossômico 16S/genética , Clima Desértico , Bactérias/genética , Proteobactérias , Biodiversidade , Microbiota/genética , Bacteroidetes/genética , Genômica , Microbiologia do Solo , Solo/química
4.
Public Health ; 225: 311-319, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37972494

RESUMO

OBJECTIVES: In 2020, Brazil experienced two concurrent public health challenges related to respiratory disease: wildfires and increased mortality due to the coronavirus (COVID-19) pandemic. Smoke from these wildfires contributed to a variety of air pollutants, including fine particulate matter (PM2.5). The present study aims to investigate the effects of environmental and socio-economic factors on COVID-19 hospitalisation in the Pantanal. STUDY DESIGN: Ecological retrospective study. METHODS: We applied a multilevel negative binomial model to relate monthly hospitalisation data with environmental variables. RESULTS: We showed that monthly PM2.5 concentration levels had the greatest influence on the increase in hospitalisations by COVID-19 in the elderly (23 % increase). The Gini index, a coefficient that reflects income inequalities, also had a positive association with COVID-19 hospitalisations (18 % increase). Higher temperatures and humidity were protective factors, showing a 15 % and 14 % decrease in hospitalisations, respectively. The results of the present study suggest that high PM2.5 exposure contributed to the increase in COVID-19 hospitalisations, as did the social inequalities of each municipality. CONCLUSIONS: The present study highlights the importance of gathering evidence supported by multiple information sources to guide decision-making and identify populations needing better public health systems.


Assuntos
COVID-19 , Incêndios Florestais , Humanos , Idoso , Fumaça/efeitos adversos , Áreas Alagadas , Estudos Retrospectivos , Brasil/epidemiologia , COVID-19/epidemiologia , Material Particulado/análise
5.
Eur J Prosthodont Restor Dent ; 30(3): 169-187, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35333010

RESUMO

This study aimed to perform a systematic review and meta-analysis to analyze the results obtained clinically for bar-clip versus stud-retainers in overdentures. Three databases (PubMed Central, MEDLINE, and BvSalud) were used beyond a manual search. The study followed strictly the inclusion and exclusion criteria, considering the PICO strategy. For the risk of bias and quality assessment of studies, in the case of RCT, there were six domains of analysis, and for non-RCT studies, the Modified Newcastle-Ottawa Scale was performed. A meta-analysis was developed using the available data for marginal bone loss (MBL) and survival rate. 25 studies were included. The stud-retentor had the lowest implant SR (87.6%) and the greatest MBL (1.96 mm). For the bar-clip system, the mean survival rate was 95.91%, with only 4 studies included for this system, and the mean MBL was 1.13 mm. Only 3 studies directly compared both systems quantitatively, showing a significantly greater MBL toward the stud-retention group. The results may not allow determination of the best system for overdenture (stud retentor or bar-clip). Therefore, most of the studies suggested the stud-retentor as a more preferable system due to better distribution of forces, biological peri-implant behavior, low-cost, and ease for removal facilitating the sanitization and/or repair.


Assuntos
Implantes Dentários , Revestimento de Dentadura , Prótese Dentária Fixada por Implante , Retenção de Dentadura , Mandíbula , Instrumentos Cirúrgicos
6.
J Endocrinol Invest ; 44(3): 609-619, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32686043

RESUMO

PURPOSE: Data on endothelial derangements in patients with non-functioning adrenal incidentaloma (NFAI) are scarce. METHODS: We investigated if NFAI patients present clinical, biochemical and endothelial alterations compared to individuals without an adrenal lesion and also the associations among these variables. Forty-two NFAI and 40 controls were evaluated. NFAI diagnosis and controls were defined according to the current guidelines and based on a normal adrenal imaging exam, respectively. Body composition was evaluated by dual emission X-ray absorptiometry. Endothelial reactivity was assessed by two methods: tonometry (Endo-PAT®) and laser speckle contrast imaging (LSCI). RESULTS: There were no differences between groups regarding age, gender, ethnicity, smoking status, and statin use. The frequency of metabolic syndrome according to the International Diabetes Federation criteria was 69% and 57.9%, respectively in NFAI and controls (p = 0.36), whereas the atherosclerotic cardiovascular disease (ASCVD) risk was 63.4% and 66.7% (p = 0.81). The clinical, laboratory, and anthropometric characteristics, as well as body composition, were similar between the groups. Additionally, any differences between groups were observed on endothelial reactivity tests. Nevertheless, we noted an association between cortisol levels after 1 mg-dexamethosone suppression test (1 mg-DST) and the duration of post-occlusive reactive hyperemia tested on microcirculation (r = 0.30; p = 0.03). NFAI patients require more antihypertensive drugs to achieve blood pressure control (p = 0.04). The number of antihypertensive drugs used to control blood pressure correlated with cortisol levels after 1 mg-DST (r = 0.29; p = 0.03). CONCLUSIONS: Since both groups herein investigated had a high frequency of metabolic syndrome and ASCVD risk, it might explain similarities observed on endothelial reactivity. Nevertheless, prolonged reactive hyperemia response on microcirculation was correlated with cortisol levels under suppression.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Biomarcadores/sangue , Doenças Cardiovasculares/diagnóstico , Dexametasona/antagonistas & inibidores , Hidrocortisona/sangue , Hiperemia/diagnóstico , Síndrome Metabólica/diagnóstico , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Hiperemia/sangue , Hiperemia/etiologia , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Prognóstico
7.
BMC Public Health ; 21(1): 1920, 2021 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-34686158

RESUMO

BACKGROUND: Adverse childhood experiences (ACEs) increases vulnerability to externalising disorders such as substance misuse. The study aims to determine the prevalence of ACEs and its association with substance misuse. METHODS: Data from the Consortium on Vulnerability to Externalising Disorders and Addictions (cVEDA) in India was used (n = 9010). ACEs were evaluated using the World Health Organisation (WHO) Adverse Childhood Experiences International Questionnaire whilst substance misuse was assessed using the WHO Alcohol, Smoking and Substance Involvement Screening Test. A random-effects, two-stage individual patient data meta-analysis explained the associations between ACEs and substance misuse with adjustments for confounders such as sex and family structure. RESULTS: 1 in 2 participants reported child maltreatment ACEs and family level ACEs. Except for sexual abuse, males report more of every individual childhood adversity and are more likely to report misusing substances compared with females (87.3% vs. 12.7%). In adolescents, family level ACEs (adj OR 4.2, 95% CI 1.5-11.7) and collective level ACEs (adj OR 6.6, 95% CI 1.4-31.1) show associations with substance misuse whilst in young adults, child level ACEs such as maltreatment show similar strong associations (adj OR 2.0, 95% CI 1.1-3.5). CONCLUSION: ACEs such as abuse and domestic violence are strongly associated with substance misuse, most commonly tobacco, in adolescent and young adult males in India. The results suggest enhancing current ACE resilience programmes and 'trauma-informed' approaches to tackling longer-term impact of ACEs in India. FUNDING: Newton Bhabha Grant jointly funded by the Medical Research Council, UK (MR/N000390/1) and the Indian Council of Medical Research (ICMR/MRC-UK/3/M/2015-NCD-I).


Assuntos
Experiências Adversas da Infância , Maus-Tratos Infantis , Violência Doméstica , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
8.
Agric Syst ; 190: 103098, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-36567886

RESUMO

CONTEXT: In Latin America, the so-called informal sector associated with family farming and the agroecology movements were instrumental at coping with and adapting to the COVID-19 challenges. OBJECTIVE: To assess the nature and extent of the early initiatives (first three months) deployed by this informal sector to cope with and adapt to the impacts of the COVID-19 pandemic on food production and consumption in several countries of the region. METHODS: We used key used informant consultation (n = 168), an online survey (n = 125) and the detailed characterisation of regional case studies (n = 4). Textual data was analysed and categorised using Reinert's method, combined with similarity analysis. RESULTS AND CONCLUSIONS: 65% of the initiatives were 'local' in terms of geographic reach, 30% of them started within the first month after the pandemic and most of them were urban or urban-rural, whereas only 29% of them were exclusively rural. The analysis of the textual information captured through the survey revealed four major types of initiatives that were deployed or adapted in response to COVID-19:1.Direct producer-to-consumer food sales, generally existing before the COVID-19 crisis but adapted/strengthened to cope with it;2.Short value chains that linked rural and urban organisations and individuals supported by national or local governments, readapted through new health and safety protocols;3.Newly developed support and training programs on sustainable food production for self-consumption or local commerce, in rural, urban or peri-urban settings;4.Food assistance and aid initiatives focusing on vulnerable populations, relying on solidarity networks associated with the agroecological movement. SIGNIFICANCE: The pandemic highlighted the key role played by local food systems and value chains and the need to strengthening them through public policies, as a way to build food resilience in times of crisis.

9.
Osteoarthritis Cartilage ; 28(2): 173-181, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31830591

RESUMO

OBJECTIVES: We investigated whether baseline scores for a self-report trait linked to central mechanisms predict 1 year pain outcomes in the Knee Pain in the Community cohort. METHOD: 1471 participants reported knee pain at baseline and responded to a 1-year follow-up questionnaire, of whom 204 underwent pressure pain detection thresholds (PPTs) and radiographic assessment at baseline. Logistic and linear regression models estimated the relative risks (RRs) and associations (ß) between self-report traits, PPTs and pain outcomes. Discriminative performance for each predictor was compared using receiver-operator characteristics (ROC) curves. RESULTS: Baseline Central Mechanisms trait scores predicted pain persistence (Relative Risk, RR = 2.10, P = 0.001) and persistent pain severity (ß = 0.47, P < 0.001), even after adjustment for age, sex, BMI, radiographic scores and symptom duration. Baseline joint-line PPTs also associated with pain persistence (RR range = 0.65 to 0.68, P < 0.02), but only in univariate models. Lower baseline medial joint-line PPT was associated with persistent pain severity (ß = -0.29, P = 0.013) in a fully adjusted model. The Central Mechanisms trait model showed good discrimination of pain persistence cases from resolved pain cases (Area Under the Curve, AUC = 0.70). The discrimination power of other predictors (PPTs (AUC range = 0.51 to 0.59), radiographic OA (AUC = 0.62), age, sex and BMI (AUC range = 0.51 to 0.64), improved significantly (P < 0.05) when the central mechanisms trait was included in each logistic regression model (AUC range = 0.69 to 0.74). CONCLUSION: A simple summary self-report Central Mechanisms trait score may indicate a contribution of central mechanisms to poor knee pain prognosis.


Assuntos
Artralgia/fisiopatologia , Sensibilização do Sistema Nervoso Central , Osteoartrite do Joelho/fisiopatologia , Autorrelato , Idoso , Ansiedade/psicologia , Artralgia/psicologia , Catastrofização/psicologia , Cognição , Depressão/psicologia , Fadiga/fisiopatologia , Feminino , Seguimentos , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/psicologia , Limiar da Dor , Pressão , Transtornos do Sono-Vigília/fisiopatologia
10.
Nanotechnology ; 31(13): 135207, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-31825904

RESUMO

Active metasurfaces with novel visible and infrared (vis/IR) functionalities represent an exciting, growing area of research. Rectification of vis/IR frequencies would produce needed direct current (DC) with no inherent frequency limitation (e.g. no semiconducting bandgap). However, controlling the materials and functionality of (nano)rectennas for rectifying 100 s of THz to the visible regime is a daunting challenge, because of the small features and simultaneously the need to scale up to large sizes in a scalable platform. An active metasurface of a planar array of nanoscale antennas on top of rectifying vertical diodes is a 'nanorectenna array' or 'microrectenna array' that rectifies very high frequencies in the infrared, or even higher frequencies up to the visible regime. We employ a novel strategy for forming optical nanorectenna arrays using scalable patterning of Au nanowires, demonstrate strong evidence for spectral-selective high-frequency rectification, characteristic of optical antennas. We discover a previously unreported out-of-equilibrium electron energy distribution, i.e. hot electrons arising from plasmonic resonance absorption in an optical antenna characterized by an effective temperature, and how this effect can significantly impact the observed rectification.

11.
Anim Genet ; 51(2): 210-223, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31944356

RESUMO

Brazilian beef cattle are raised predominantly on pasture in a wide range of environments. In this scenario, genotype by environment (G×E) interaction is an important source of phenotypic variation in the reproductive traits. Hence, the evaluation of G×E interactions for heifer's early pregnancy (HP) and scrotal circumference (SC) traits in Nellore cattle, belonging to three breeding programs, was carried out to determine the animal's sensitivity to the environmental conditions (EC). The dataset consisted of 85 874 records for HP and 151 553 records for SC, from which 1800 heifers and 3343 young bulls were genotyped with the BovineHD BeadChip. Genotypic information for 826 sires was also used in the analyses. EC levels were based on the contemporary group solutions for yearling body weight. Linear reaction norm models (RNM), using pedigree information (RNM_A) or pedigree and genomic information (RNM_H), were used to infer G×E interactions. Two validation schemes were used to assess the predictive ability, with the following training populations: (a) forward scheme-dataset was split based on year of birth from 2008 for HP and from 2011 for SC; and (b) environment-specific scheme-low EC (-3.0 and -1.5) and high EC (1.5 and 3.0). The inclusion of the H matrix in RNM increased the genetic variance of the intercept and slope by 18.55 and 23.00% on average respectively, and provided genetic parameter estimates that were more accurate than those considering pedigree only. The same trend was observed for heritability estimates, which were 0.28-0.56 for SC and 0.26-0.49 for HP, using RNM_H, and 0.26-0.52 for SC and 0.22-0.45 for HP, using RNM_A. The lowest correlation observed between unfavorable (-3.0) and favorable (3.0) EC levels were 0.30 for HP and -0.12 for SC, indicating the presence of G×E interaction. The G×E interaction effect implied differences in animals' genetic merit and re-ranking of animals on different environmental conditions. SNP marker-environment interaction was detected for Nellore sexual precocity indicator traits with changes in effect and variance across EC levels. The RNM_H captured G×E interaction effects better than RNM_A and improved the predictive ability by around 14.04% for SC and 21.31% for HP. Using the forward scheme increased the overall predictive ability for SC (20.55%) and HP (11.06%) compared with the environment-specific scheme. The results suggest that the inclusion of genomic information combined with the pedigree to assess the G×E interaction leads to more accurate variance components and genetic parameter estimates.


Assuntos
Bovinos/fisiologia , Interação Gene-Ambiente , Genoma , Comportamento Sexual Animal , Maturidade Sexual/genética , Animais , Brasil , Bovinos/genética , Feminino , Genômica , Masculino , Modelos Genéticos
12.
Br J Nurs ; 29(8): S34-S42, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32324464

RESUMO

HIGHLIGHTS: A lower central venous catheter (CVC) infection rate suggests an improvement in practice and education. CVC infection remains a complication that often requires significant health care resources. Use of tunneled CVC and patient education on catheter care reduces CVC infection rates. OBJECTIVES: CVC infection is one of the most frequent, life-threatening complications in home parenteral nutrition (HPN) patients. Our objective was to conduct a 5-year retrospective chart review regarding CVC infections in 3 adult HPN programs. METHODS: Data were collected from the Canadian HPN Registry and patient charts that include demography, infection diagnosis, blood cultures, and treatments. RESULTS: Results are reported as median (range) ± standard error of mean or population frequency. Eighty-one charts were reviewed. Mean age was 51.98 ± 1.71 years. Short bowel syndrome (54.3%) was the primary diagnosis, with 36 months (range, 1324 months) median length of HPN therapy. Forty-seven subjects (58%) had infections over a 5-year period. Of these, there were 144 sepsis events. There was positive correlation (r=0.423; P<0.001) between number of infections and HPN duration. The median length of time the CVC was in place was 281 (range, 14-4380) days. There were 66.7% tunneled CVCs; 25.9% peripherally inserted central catheters (PICCs), and 7.4% implanted venous port. In this sample, there was no association between line infection and catheter type. Most patients presented with fever (58.3%) and chills (38.2%). Blood cultures were done (89.6%), and coagulase negative Staphylococcus was the resulting pathogen present in 25.7%. Patients with bloodstream infection were treated for 17.9 ± 1.2 days with combination antibiotics (22.2%). Overall, the CVC infection rate was 0.97 per 1000 catheter days. CONCLUSION: We found the standard approach to infection prevention is comparable to reports in literature. However, a subset of patients with multiple CVC infections require education with an emphasis on preventive techniques in order to reduce the incidence of infection.


Assuntos
Infecções Relacionadas a Cateter/epidemiologia , Cateteres Venosos Centrais/efeitos adversos , Nutrição Parenteral no Domicílio , Canadá/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos
13.
Osteoarthritis Cartilage ; 27(3): 435-443, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30448531

RESUMO

OBJECTIVE: To establish "normal" ranges for synovial thickness and effusion detected by ultrasound (US) and to determine cut-offs associated with knee pain (KP) and radiographic knee osteoarthritis (RKOA) in the community. METHODS: 147 women and 152 men ≥40 years old were randomly selected from the Nottingham KP and Related Health in the Community (KPIC) cohort (n = 9506). The "normal" range was established using the percentile method in 163 participants who had no KP and no RKOA. Optimal (maximum sensitivity and specificity) and high specificity (90%) cut-offs were established using receiver operating characteristic (ROC) curve analysis in a comparison between people with both KP and RKOA and normal controls. RESULTS: Effusion and synovial hypertrophy differed by gender but not by age or laterality, therefore gender-specific reference limits were estimated. However, the "normal" ranges between men and women were similar for effusion (0-10.3 mm vs 0-9.8 mm), but different for synovial hypertrophy (0-6.8 mm vs 0-5.4 mm). Power Doppler Signal (PDS) in the healthy controls was uncommon (1.2% in men and 0.0% in women). The optimal cut-off was 7.4 mm for men and 5.3 mm for women for effusion, and 3.7 and 1.6 for hypertrophy respectively. The high specificity cut-off was 8.9 for men and 7.8 for women for effusion, and 5.8 and 4.2 for hypertrophy respectively. CONCLUSIONS: US effusion and synovial hypertrophy but not PDS are common, but differ by gender, in community-derived people without painful knee OA. Currently used cut-offs for abnormality need reappraisal.


Assuntos
Osteoartrite do Joelho/diagnóstico por imagem , Membrana Sinovial/diagnóstico por imagem , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/patologia , Curva ROC , Radiografia , Valores de Referência , Sensibilidade e Especificidade , Fatores Sexuais , Membrana Sinovial/patologia , Ultrassonografia
14.
Opt Express ; 27(14): 19996-20011, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503752

RESUMO

We present a digital technique able to monitor and compensate for the mode-dependent losses (MDL) in space-division multiplexing (SDM) transmission systems. The working principle of the technique is based on the analysis of the received signal samples in the higher-order Poincaré spheres (HoPs). When an arbitrary pair of tributaries is represented in the respective HoPs, the effect of the MDL can be modeled as a simple shift of the constellation points in a such sphere. Therefore, the MDL can be estimated by computing those shifts over all the HoPs and the induced signal distortions can be compensated by re-centering all the constellations in the respective HoPs. It should be highlighted that the proposed technique is scalable with an arbitrary number of spatial channels, modulation format agonistic and free of training sequences. The HoPs-based MDL monitoring (compensation) technique allows the MDL estimation (compensation) up to values of ≈ 6 dB. The proposed technique can partially compensate the MDL distortion, making a MDL sensitive algorithm in an insensitive one. When the proposed technique assists a HoPs-based space-demultiplexing algorithm, it provides signal-to-noise ratio (SNR) enhancements of 2, 4 and 8 dB for PM-QPSK, PM-16QAM and PM-64QAM signals, respectively, for the particular case of a SDM-based transmission system with a spatial diversity of 2 and 2 dB of MDL.

15.
J Anim Ecol ; 88(8): 1168-1177, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31106413

RESUMO

Theory suggests that non-trophic interactions can be a major mechanism behind community stability and persistence, but community-level empirical data are scarce, particularly for effects on species interactions mediated through changes in the physical environment. Here, we explored how ecosystem engineering effects can feed back to the engineer, not only modulating the engineer's population density (node modulation) but also affecting its interactions with other species (link modulation). Gall induction can be viewed as ecosystem engineering since galls serve as habitat for other species. In a community-level field experiment, we generated treatments with reduced or elevated ecosystem engineering by removing or adding post-emergence galls to different plots of their host plant in the Brazilian Cerrado. We tested the effect of post-emergence galls on the galler, as well as on the galler-parasitoid and galler-aphid interactions. The manipulation of post-emergence galls had little effect on the galler-abundance and survivorship were not affected, and gall volume changed only slightly-but modified interactions involving the galler, parasitoid wasps and inquiline aphids. Aphid inquilines negatively affected density-dependent parasitism rates (interaction modification) likely by killing parasitised galling larvae. Post-emergence galls interfered with aphid inquilinism-likely by the provision of alternative habitat for aphids-and thus interfered with the negative effect of aphids on parasitism (modification of an interaction modification). This work is one of the few studies to demonstrate experimentally the role played by environment-mediated interaction modification at a community level in the field. Moreover, by manipulating a species' ecosystem engineering effect (post-emergence galls) instead of the species itself, we demonstrate the novel result that populations can be regulated by non-trophic effects initiated by their own activities that alter their interaction with other species. This reveals that indirect interactions mediated via the environment offer new pathways of feedback loops for population regulation. Our results indicate that interaction modification has the potential to be a key regulatory mechanism underlying interaction variation in nature, and play a major role in community structure, dynamics and stability.


Assuntos
Afídeos , Vespas , Animais , Brasil , Ecossistema , Interações Hospedeiro-Parasita , Insetos
17.
Osteoarthritis Cartilage ; 26(11): 1461-1473, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30099115

RESUMO

AIM: To explore risk factors that may influence knee pain (KP) through central or peripheral mechanisms. METHODS: A questionnaire-based prospective community cohort study with KP defined as pain in or around a knee on most days for at least a month. Baseline prevalence, and one year incidence and progression (KP worsening) were examined. Central (e.g., Pain Catastrophizing Scale (PCS)) and peripheral (e.g., significant injury) risk factors were examined. Adjusted odds ratio (OR) and 95% confidence interval (CI) were calculated using logistic regression. Proportional risk contribution (PRC) was estimated using receiver-operator-characteristic (ROC) analysis. RESULTS: Of 9506 baseline participants, 4288 (45%) had KP (men 1826; women, 2462). KP incidence was 12% (men 11%, women 13%), and KP progression 19% (men 16%, women 21%) at one year. While both central and peripheral factors contributed to prevalence, central factors contributed more to progression, and peripheral factors more to incidence of KP. For example, although PCS (OR 2.06, 95% CI 1.88-2.25) and injury (5.62, 4.92-6.42) associated with KP prevalence, PCS associated with progression (2.27, 1.83-2.83) but not incidence (1.14, 0.86-1.52), whereas injury more strongly associated with incidence (69.27, 24.15-198.7) than progression (2.52, 1.48-4.30). The PRC of central and peripheral factors were 19% and 23% for prevalence, 14% and 29% for incidence, and 29% and 5% for progression, respectively. CONCLUSIONS: Both central and peripheral risk factors influence KP but relative contributions may differ in terms of development (mainly peripheral) and progression (mainly central). Further study of such relative contributions may inform primary and secondary prevention strategies.


Assuntos
Artralgia/epidemiologia , Articulação do Joelho , Osteoartrite do Joelho/complicações , Medição de Risco/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artralgia/diagnóstico , Artralgia/etiologia , Progressão da Doença , Feminino , Seguimentos , Nível de Saúde , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico , Medição da Dor , Prevalência , Estudos Prospectivos , Curva ROC , Fatores de Risco , Inquéritos e Questionários , Reino Unido/epidemiologia
18.
J Anim Breed Genet ; 135(3): 208-220, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29878496

RESUMO

Bioeconomic models were developed to calculate economic values (EV) for economically important traits in beef cattle, to evaluate the impact of these traits on production profitability, to assess possible market changes with a payment system and to develop economic selection indexes for Angus cattle for two production systems. Two beef cattle production systems were simulated as follows: a cow-calf cycle (CC) and a complete cycle (CoC). Following selection, positive changes in the EV were observed. In the CC, each 1.0% increment in weaning weight (WW), weaning rate (WR) and pregnancy rate (PR) resulted in increases in US$ 1.30, US$ 3.68 and US$ 3.55 per cow/year in profit, respectively. In the CoC, EV of US$ 1.01, US$ 1.79, US$ 1.19, US$ 1.34, US$ 6.84 and US$ 7.86 per cow/year were obtained for WW, year weight, yearling weight, final weight, WR and PR, respectively. The payment system for carcass quality showed that the scenario considering that 100% of the animals displayed uniform carcasses exhibited the highest EV and was considered optimal. Considering the sensitivity analysis, the price paid per animal was the factor that most affected the EV in both systems. The selection indexes obtained may be used in similar production systems, and the use of EV and selection indexes are important tools for any production system with positive change in profit after selection.


Assuntos
Bovinos/fisiologia , Cruzamentos Genéticos , Seleção Genética , Seleção Artificial , Criação de Animais Domésticos , Animais , Peso Corporal , Bovinos/genética , Feminino , Masculino , Modelos Econômicos , Gravidez
19.
Acute Med ; 17(4): 229-231, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30882107

RESUMO

Cardiovascular signs and symptoms can prevail in both hypothyroidism and hyperthyroidism. Case 1: 30-year-old female with acute right heart failure as first manifestation of Graves' disease. It illustrates some of its cardiovascular complications, particularly pulmonary hypertension, tricuspid regurgitation, atrial fibrillation, mitral valve prolapse and mitral regurgitation. Case 2: 83-year-old-man with a severe primary hypothyroidism/myxoedema crisis presented to emergency department with extreme bradyarrhythmia with hemodynamic impact and heart failure signs, which led to implantation of definitive pacemaker. Thyroid disorders are treatable entities and most cardiovascular changes are reversible. Early diagnosis is mandatory and can avoid severe complications and, eventually, invasive therapeutics interventions. Pulmonary hypertension and acute heart failure, especially in young adults, should be screened for underlying hyperthyroidism.


Assuntos
Insuficiência Cardíaca , Mixedema , Crise Tireóidea , Adulto , Idoso de 80 Anos ou mais , Feminino , Doença de Graves/complicações , Insuficiência Cardíaca/etiologia , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/etiologia , Mixedema/complicações , Crise Tireóidea/complicações
20.
Mol Ecol ; 26(20): 5541-5551, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28802076

RESUMO

Acid mine drainage (AMD) is characterized by an acid and metal-rich run-off that originates from mining systems. Despite having been studied for many decades, much remains unknown about the microbial community dynamics in AMD sites, especially during their early development, when the acidity is moderate. Here, we describe draft genome assemblies from single cells retrieved from an early-stage AMD sample. These cells belong to the genus Hydrotalea and are closely related to Hydrotalea flava. The phylogeny and average nucleotide identity analysis suggest that all single amplified genomes (SAGs) form two clades that may represent different strains. These cells have the genomic potential for denitrification, copper and other metal resistance. Two coexisting CRISPR-Cas loci were recovered across SAGs, and we observed heterogeneity in the population with regard to the spacer sequences, together with the loss of trailer-end spacers. Our results suggest that the genomes of Hydrotalea sp. strains studied here are adjusting to a quickly changing selective pressure at the microhabitat scale, and an important form of this selective pressure is infection by foreign DNA.


Assuntos
Bacteroidetes/classificação , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Genoma Bacteriano , Mineração , Ácidos , Bacteroidetes/genética , DNA Bacteriano/genética , Ecossistema , Evolução Molecular , Filogenia , Análise de Sequência de DNA , Análise de Célula Única
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