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Strong coupling of organic molecules to the vacuum field of a nanoscale cavity can be used to modify their chemical and physical properties. We extend the Tavis-Cummings model for molecular ensembles and show that the often neglected interaction terms arising from the static dipole moment and the dipole self-energy are essential for a correct description of the light-matter interaction in polaritonic chemistry. On the basis of a full quantum description, we simulate the excited-state dynamics and spectroscopy of MgH+ molecules resonantly coupled to an optical cavity. We show that the inclusion of static dipole moments and the dipole self-energy is necessary to obtain a consistent model. We construct an efficient two-level system approach that reproduces the main features of the real molecular system and may be used to simulate larger molecular ensembles.
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We present a novel technique for in-vacuum cavity-enhanced UV spectroscopy that allows nearly continuous measurements over several days, minimizing mirror degradation caused by high-power UV radiation. Our method relies on pulsing of the cavity's internal power, which increases the UV intensity to maximum only for short periods when the studied atom is within the cavity mode volume while keeping the average power low to prevent mirror degradation. Additionally, this method significantly decreases laser-induced background on charged particle detectors. The described 244â nm laser system is designed for 1S-2S two-photon CW spectroscopy of muonium in the Mu-MASS project. It was tested to provide intracavity powers above 20â W, requiring maintenance only a few times a day. The pulsing technique demonstrates minimal impact on the radiation frequency, with no observed shifts exceeding 15â kHz. Our approach represents a promising new technique for high-precision spectroscopy of atoms in harsh UV environments and demonstrates the feasibility of CW spectroscopy of muonium.
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Internal erosion is the most important failure mechanism of earth and rockfill dams. Since this type of erosion develops internally and silently, methodologies of data acquisition and processing for dam monitoring are crucial to guarantee a safe operation during the lifespan of these structures. In this context, artificial intelligence techniques show up as tools that can simplify the analysis and verification process not of the internal erosion itself, but of the effects that this pathology causes in the response of the dam to external stimuli. Therefore, within the scope of this paper, a methodological framework for monitoring internal erosion in the body of earth and rockfill dams will be proposed. For that, artificial intelligence methods, especially deep neural autoencoders, will be used to treat the acoustic data collected by geophones installed on a dam. The sensor data is processed to identify patterns and anomalies as well as to classify the dam's structural health status. In short, the acoustic dataset is preprocessed to reduce its dimensionality. In this process, for each second of acquired data, three parameters are calculated (Hjorth parameters). For each parameter, the data from all the available sensors are used to calibrate an autoencoder. Then, the reconstruction error of each autoencoder is used to monitor how far from the original (normal) state the acoustic signature of the dam is. The time series of reconstruction errors are combined with a cumulative sum (CUSUM) algorithm, which indicates changes in the sequential data collected. Additionally, the outputs of the CUSUM algorithms are treated by a fuzzy logic framework to predict the status of the structure. A scale model is built and monitored to check the effectiveness of the methodology hereby developed, showing that the existence of anomalies is promptly detected by the algorithm. The framework introduced in the present paper aims to detect internal erosion inside dams by combining different techniques in a novel context and methodological workflow. Therefore, this paper seeks to close gaps in prior studies, which mostly treated just parts of the data acquisition-processing workflow.
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Inteligencia Artificial , Lógica Difusa , Acústica , Algoritmos , Redes Neurales de la ComputaciónRESUMEN
We demonstrate the superior performance of dielectric fluoride coatings versus oxide coatings in long term vacuum operation of a high power deep-ultraviolet enhancement cavity. In ultra-high vacuum (10-8 mbar), the fluoride optics can maintain up to 10 W of stable intracavity power on one hour time scales, a record-high at these vacuum levels, whereas for the oxide optics, we observe rapid degradation at lower intracavity powers with a rate that increases with power. After observing degradation in high vacuum, we can recover the fluoride and oxide optics with oxygen; however, this recovery process becomes ineffective after several applications. For the fluoride optics, we see that initial UV conditioning in an oxygen environment helps to improve the performances of the optics. In oxygen-rich environments from â¼10-4 mbar, the fluoride optics can stably maintain up to 20 W of intracavity power on several-hour time scales whereas for the oxide optics there is immediate degradation with a rate that increases with decreasing oxygen pressure.
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To evaluate factors affecting corneal endothelial cell density (ECD) under enucleation and preservation time studies at Eye Bank of the Federal District of Brazil. We conducted a case-control study collecting data from 1128 corneas where death-to-enucleation time and enucleation-to-preservation time were within 24 h. Low cell count were those corneas with an ECD less than 2000 cells/mm2 and high cell count was defined as those with ECD greater than 2000 cells/mm2. We calculated the independent risk factors related to: cause of death, donor age, death-to-enucleation time, enucleation-to-preservation time and primary graft failure. Correlation analysis was used to assess which parameters influence ECD: death-to-enucleation time, enucleation-to-preservation time, average cell area (AVE), coefficient of variation and percentage of hexagonal cells. Of the total number of corneas, 1004 had ECD data and were selected for the study. 87.4% (n = 877) had high cell counts with 2699 ± 412 cells/mm2. The mean donor age was 38.8 ± 16 years. The most common causes of death were external causes (48.6%, n = 488). Longer times from death-to-enucleation, up to 24 h were not associated with a decrease in ECD (OR 0.58; P = 0.44) or risk of graft survival (P = 0.74). Enucleation-to-preservation intervals greater than 12 h showed increased risk of graft survival (P = 0.04). AVE was the main parameter for ECD (R2 = 0.96, P < 0.001). The overall graft survival rate was 98.2% (n = 761). Donors with 40 years of age and above did not present a higher risk of graft survival (P = 0.09). We suggest that the maximum time from death-to-enucleation should be 24 h, assuming the body has been refrigerated after 6 h; and from enucleation-to-preservation time of 12 h, followed by proper processing and cornea morphology examination.
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Trasplante de Córnea , Células Endoteliales , Endotelio Corneal , Adulto , Estudios de Casos y Controles , Recuento de Células , Córnea , Bancos de Ojos , Humanos , Persona de Mediana Edad , Preservación de Órganos , Donantes de Tejidos , Adulto JovenRESUMEN
PURPOSE: To evaluate the stability of interdental papilla filling using hyaluronic acid (HA) to treat black triangles in esthetic regions. METHODS: The protocol was registered in PROSPERO. Six databases (PubMed, Scopus, Embase, Lilacs, SciELO, and Web of Science) were used as primary search sources, and OpenGrey and OpenThesis were used to capture the "gray literature." Only before-after studies were included. The JBI Checklist assessed the risk of bias. Only four studies met the inclusion criteria and were considered for the analyses. The studies were published from 2010 to 2016. All studies presented a low risk of bias. Considering the studies do not have control groups, a weighted average by sample size was calculated to obtain a general estimate of the percentage of papillary filling after 6 months and the number of HA applications. RESULTS: The studies showed the percentage of papillary reconstruction after 6 months of application, the weighted average by sample size was 77.41% (SD = 20.68), with an average number of applications of 3.17 (SD = 0.31). CONCLUSION: The application of HA may be used to repair anesthetic defects in the papilla. CLINICAL SIGNIFICANCE: Interdental papilla reconstruction with injectable HA is an option of nonsurgical treatment for interdental papilla deficiencies. However, there is still concern about the quality of the evidence available, considering that studies with different experimental designs can produce contradictory results. Moreover, further understanding is required on the stability of tissue gain promoted by HA in black triangles.
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Encía , Ácido Hialurónico , Estética Dental , Encía/anatomía & histología , HumanosRESUMEN
OBJECTIVE. The purpose of this study was to determine whether application of a proprietary image-processing algorithm would allow a reduction in the necessary administered activity for molecular breast imaging (MBI) examinations. MATERIALS AND METHODS. Images from standard-dose MBI examinations (300 MBq 99mTc-sestamibi) of 50 subjects were analyzed. The images were acquired in dynamic mode and showed at least one breast lesion. Half-dose MBI examinations were simulated by summing one-half of the dynamic frames and were processed with the algorithm under study in both a default and a preferred filter mode. Two breast radiologists independently completed a set of two-alternative forced-choice tasks to compare lesion conspicuity on standard-dose images, half-dose images, and the algorithm-processed half-dose images in both modes. RESULTS. Relative to the standard-dose images, the half-dose images were preferred in 4, the default-filtered half-dose images in 50, and preferred-filtered half-dose images in 76 of 100 readings. Compared with standard-dose images, in terms of lesion conspicuity, the half-dose images were rated better in 2, equivalent in 6, and poorer in 92 of 100 readings. The default-filtered half-dose images were rated better, equivalent, or poorer in 13, 73, and 14 of 100 readings. The preferred-filtered half-dose images were rated as better, equivalent, or poorer in 55, 34, and 11 of 100 readings. CONCLUSION. Compared with that on standard-dose images, lesion conspicuity on images obtained with the algorithm and acquired at one-half the standard dose was equivalent or better without compromise of image quality. The algorithm can also be used to decrease imaging time with a resulting increase in patient comfort and throughput.
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Algoritmos , Enfermedades de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Imagen Molecular/métodos , Dosis de Radiación , Anciano , Femenino , Humanos , Persona de Mediana Edad , CintigrafíaRESUMEN
Silviculture can be considered a sustainable alternative to the extraction of wood from natural forests in Brazil. However, the high demand for wood products has decreased the area of natural Cerrado due to land transformation for forestry activities. This transformation could lead to the loss of species, including insects that cannot tolerate the new environment dominated by exotic plant species. This study aims to evaluate whether the presence of an extensive Eucalyptus silviculture in the Brazilian Cerrado decreases the integrity of nearby riparian environments and, consequently, decreases odonate diversity. Thirteen ponds were selected in patches of Cerrado embedded within a matrix of Eucalyptus silviculture in order to assess habitat integrity of ponds and their riparian zones and collect adult odonates. The physical integrity of the study sites was measured using a Habitat Integrity Index (HII) designed to determine the degree of conservation of aquatic environments. The HII of the study sites varied between 0.44 and 0.80, indicating differences in the degree of conservation. Therefore, a positive relationship was found between odonate richness and abundance and HII, and between the abundance of zygopterans and anisopterans and HII. These findings may be due to the fact that these insects are adapted to the natural resources maintained at the most conserved habitats, and which were lost in degraded riparian zones, such as the presence of aquatic vegetation and a diversity of organic debris on pond banks. We conclude that the conversion of natural areas to Eucalyptus silviculture can alter the integrity of nearby riparian zones and, consequently, odonate diversity.Graphical abstract.
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Eucalyptus , Odonata , Animales , Biodiversidad , Brasil , Conservación de los Recursos Naturales , Ecosistema , Monitoreo del AmbienteRESUMEN
The qualities of food, mainly of animal origin, have always been of concern to consumers. It is known that the composition of animals' diets can influence the composition of the foods produced, such as milk. Thus, the objective of this study was to evaluate diets with cactus pear in combination with different forages for F1 Holstein/Zebu cows on the chemical composition and fatty acid profile of milk. Two simultaneous 4 × 4 Latin squares were used in the experimental design. Four experimental diets were used: Diet 1, sorghum silage as the only roughage; Diet 2, sorghum silage combined with cactus pear in a proportion of 50% of the roughage (dry matter basis); Diet 3, elephant grass (Pennisetum purpureum cv. Roxo) as the only roughage; and Diet 4, elephant grass combined with cactus pear in a proportion of 50% of the roughage. The roughage:concentrate ratio was 75:25. The milk urea nitrogen was higher (16.08 mg/dL) in the milk of cows fed the diet with only elephant grass than that of milk from the other diet groups. The other analyzed variables of the chemical composition of milk were not influenced by the diets. However, there was a change in the sum of the saturated and monounsaturated fatty acids. The content of C16:0 fatty acid was higher and that of C18:0 was lower in the milk of cows fed the cactus pear diets than in that of cows fed the other diets. Higher levels of oleic acid were observed in the milk of cows fed with diets containing elephant grass than those in the milk of the cows in the sorghum forage groups. Conjugated linoleic acid (CLA) was higher in the milk of cows fed cactus pear than in that of the other cows. The combination of cactus pear with elephant grass or sorghum silage in the diet did not alter the chemical composition of milk. However, it influenced the fatty acid profile.
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Alimentación Animal/análisis , Bovinos , Dieta/veterinaria , Fibras de la Dieta/análisis , Ácidos Grasos/química , Opuntia , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Femenino , Lactancia/efectos de los fármacos , Lactancia/fisiología , Leche/química , Sorghum , Zea maysRESUMEN
The quantitative feed restriction of lactating cows has been used in intensive production systems as a strategy to reduce production costs. However, the effects of this restriction in F1 Holstein/Zebu cows are unclear. The objective of this work was to evaluate the effect of quantitative feed restriction on nutrient intake and digestibility, nitrogen balance, feed efficiency, feed behavior, and productive performance in F1 Holstein/Zebu cows during early lactation. Sixty F1 Holstein × Zebu cows were used at the stage of initial lactation (50 ± 13 days of lactation), and they had an initial body weight (BW) of 482 ± 43 kg. The experimental arrangement adopted was a completely randomized design, with five feed restriction levels (3.39, 2.75, 2.50, 2.25, and 2.00% of BW) and 12 cows in each treatment group. In the short term (63 days), there were reductions of 45.9% and 47.2% in dry matter intake (P < 0.01) and crude protein (P < 0.01), respectively, when the diet supply was limited from 3.39% BW to 2.00% of BW. There were declines in intake of ether extract (P < 0.01) and nonfibrous carbohydrates (P < 0.01), but there was no change in daily milk production (P = 0.44) nor the daily milk production corrected to 3.5% fat (P = 0.12); the averages were 14.01 kg/day and 13.25 kg/day, respectively. Considering the lower body weight loss, feed restriction is recommended up to 2.5% of the BW.
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Bovinos/fisiología , Digestión , Ingestión de Alimentos , Ingestión de Energía , Conducta Alimentaria , Nitrógeno/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Femenino , Lactancia , Distribución AleatoriaRESUMEN
BACKGROUND: Intradialytic blood pressure (BP) measurement is currently the main parameter used for monitoring hemodynamics during hemodialysis (HD). Since BP is dependent on cardiac output and total peripheral resistance, knowledge of these parameters throughout the HD treatment would potentially be valuable. METHODS: The use of a novel non-invasive monitoring system for profiling hemodynamic response patterns during HD was explored: a whole-body bio-impedance system was used to assess cardiac index (CI), total peripheral resistance index (TPRI), cardiac power index (CPI) among other parameters in chronic HD patients from 4 medical centers. Measurements were made pre, during and post dialysis. Patients were grouped into 5 hemodynamic profiles based on their main hemodynamic response during dialysis i.e. high TPRI; high CPI; low CPI; low TPRI and those with normal hemodynamics. Comparisons were made between the groups for baseline characteristics and 1-year mortality. RESULTS: In 144 patients with mean age of 67.3 ± 12.1 years pre-dialysis hemodynamic measurements were within normal limits in 35.4% but only 6.9% overall remained hemodynamically stable during dialysis. Intradialytic BP decreased in 65 (45.1%) in whom, low CPI (47 (72.3%)) and low TPRI (18 (27.7%) were recorded. At 1-year follow-up, mortality rates were highest in patients with low CPI (23.4%) and low TPRI (22.2%). CONCLUSIONS: Non-invasive assessment of patients' response to HD provides relevant hemodynamic information that exceeds that provided by currently used BP measurements. Use of these online analyses could potentially improve the safety and performance standards of dialysis by guiding appropriate interventions, particularly in responding to hypertension and hypotension.
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Gasto Cardíaco/fisiología , Hemodinámica/fisiología , Prueba de Estudio Conceptual , Diálisis Renal/métodos , Resistencia Vascular/fisiología , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Diálisis Renal/tendencias , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/terapiaRESUMEN
Objective: This study ascertained effects of cactus pear in association with different roughage in the diet of F1 Holstein/Zebu cows on intake, nutrient digestibility, nitrogen balance, ingestive behavior and performance. Methods: Eight cows with 72 ± 11 days of lactation were used. The experimental design was simultaneous in two 4 x 4 Latin squares. Four experimental diets were used: Diet 1 - sorghum silage as exclusive roughage; Diet 2 - sorghum silage associated with cactus pear in a proportion of 50% of the roughage (dry basis); Diet 3 - elephant grass (Pennisetum purpureum cv. Roxo) as exclusive roughage; Diet 4 - elephant grass associated with cactus pear in a proportion of 50% of the roughage. The roughage:concentrate ratio was 75:25. Dry matter intake (P = 0.01) was higher with sorghum silage. Results: There were differences in dry matter intake (P = 0.01), crude protein (P <0.01), ether extract (P = 0.01), non-fibrous carbohydrates (P <0.01) and total digestible nutrients (P = 0.01) among the diets. Cactus pear in the diet reduced water intake by 44.52% (P < 0.01). The nitrogen balance was 59.71% and 27.49% lower in animals treated with exclusive sorghum silage and sorghum silage associated with cactus pear in relation to diets with elephant grass and elephant grass associated with cactus pear, respectively (P < 0.01). The diets did not influence the milk production (P = 0.70), 3.5% fat corrected milk production (P = 0.72) or feed efficiency (P = 0.61). Conclusion: The association of cactus pear with sorghum or elephant grass silage does not alter milk production, reduces the intake of dry matter and water and improves the digestibility of nutrients.
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Background: Intradialytic hypotension is a clinically significant problem, however, the hemodynamics that underlie ultrafiltration and consequent hypotensive episodes has not been studied comprehensively. Methods: Intradialytic cardiac output, cardiac power and peripheral resistance changes from pretreatment measurements were evaluated using a novel regional impedance cardiographic device (NICaS, NI Medical, Peta Tikva, Israel) in 263 hemodialysis sessions in 54 patients in dialysis units in the USA and Brazil with the goal of determining the various hemodynamic trends as blood pressure decreases. Results: Hypotensive episodes occurred in 99 (13.5%) of 736 intra- and postdialytic evaluations. The hemodynamic profiles of the episodes were categorized: (i) The cardiac power index significantly decreased in 35% of episodes by 36%, from 0.66 [95% confidence interval (CI) 0.60-0.72] to 0.43 (95% CI 0.37-0.48) [w/m2] with a small reduction in the total peripheral resistance index. (ii) The total peripheral resistance index significantly decreased in 37.4% of episodes by 33%, from 3342 (95% CI 2824-3859) to 2251 (95% CI 1900-2602) [dyn × s/cm5 × m2] with a small reduction in the cardiac power index. (iii) Both the cardiac power index and total peripheral resistance index significantly decreased in 27.3% of episodes, the cardiac power index by 25% from 0.63 (95% CI 0.57-0.70) to 0.48 (95% CI 0.42-0.53) [w/m2] and the total peripheral resistance index by 23% from 2964 (95% CI 2428-3501) to 2266 (95% CI 1891-2642). Conclusions: The hemodynamic profiles clearly define specific hemodynamic mechanisms of cardiac power reduction and/or vasodilatation as underlying intradialytic hypotensive episodes. A reduction in cardiac power (reduction of both blood pressure and cardiac output) could be the result of preload reduction due to a high ultrafiltration rate with not enough refilling or low target weight. A reduction in peripheral resistance (reduction in blood pressure and increase in cardiac output) could be the result of relative vasodilatation as arteries do not contract to compensate for volume reduction due to autonomous dysfunction. As both phenomena are independent, they may appear at the same time. Based on these results, a reduction of ultrafiltration rate and an increase in target weight to improve preload or immediate therapeutic actions to increase peripheral resistance are rational measures that could be taken to maintain blood pressure and prevent hypotensive ischemic complications in dialysis patients.
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Gasto Cardíaco , Fluidoterapia/efectos adversos , Hemodinámica , Hipotensión/etiología , Diálisis Renal/efectos adversos , Resistencia Vascular , Anciano , Presión Sanguínea , Femenino , Corazón/fisiopatología , Humanos , MasculinoRESUMEN
The purpose of this work was to verify in vitro adherence of E. corrodens and S. oralis to the surface of tongue piercings made of surgical steel, titanium, Bioplast, and Teflon. For this, 160 piercings were used for the count of Colony Forming Units (CFU) and 32 piercings for analysis under scanning electron microscopy. Of these, 96 (24 of each type) were individually incubated in 5 mL of BHI broth and 50 µL of inoculum at 37°C/24 h. The other 96 piercings formed the control group and were individually incubated in 5 mL of BHI broth at 37°C/24 h. Plates were incubated at 37°C/48 h for counting of CFU/mL and data were submitted to statistical analysis (p value <0.05). For E. corrodens, difference among types of material was observed (p < 0.001) and titanium and surgical steel showed lower bacterial adherence. The adherence of S. oralis differed among piercings, showing lower colonization (p < 0.007) in titanium and surgical steel piercings. The four types of piercings were susceptible to colonization by E. corrodens and S. oralis, and bacterial adhesion was more significant in those made of Bioplast and Teflon. The piercings presented bacterial colonies on their surface, being higher in plastic piercings probably due to their uneven and rough surface.
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Adhesión Bacteriana , Perforación del Cuerpo , Lengua/microbiología , Bacterias , Humanos , Microscopía Electrónica de Rastreo , Politetrafluoroetileno , Polivinilos , Acero , TitanioRESUMEN
Predatory mites of the family Phytoseiidae are commercialized in European and North American countries for the control of whiteflies (Insecta: Aleyrodidae). Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is one of the predators used for that purpose. This predator is not found in Brazil and in many other countries, but its introduction could promote biological control of Bemisia tabaci (Gennadius) biotype B (silverleaf whitefly) in those countries. The aim of this study was to compare two populations of A. swirskii as predators of eggs of B. tabaci of two different ages, as well as the acceptance of those populations for other food types [eggs of Tetranychus urticae Koch; larvae and protonymphs of Aleuroglyphus ovatus (Troupeau) (Astigmatina: Acaridae) and cattail pollen (Typha domingensis Persoon)]. One of the populations of A. swirskii was collected in the Republic of Benin, in tropical Africa, and the other was commercially available in The Netherlands. The comparison was done to evaluate the population with better potential for practical use, and to determine food types that could be used for mass rearing the predator. Experiments were conducted at 28 ± 1 °C, 80 ± 10 % relative humidity and 12 h photophase. Both populations were able to oviposit when fed eggs of B. tabaci, but the Netherlands population showed higher oviposition rate (2.3 and 1.6 times higher on young and older eggs, respectively). Higher predation rates were observed for eggs up to 24 h of age in comparison with older eggs. Aleuroglyphus ovatus proved to be a promising prey for possible mass rearing of this predator in Brazil, where that astigmatic mite is found naturally when pollen was used as food, no significant difference was observed for oviposition rate between populations. The results suggested a higher potential of the Netherlands population of A. swirskii for the control of B. tabaci biotype B in this country for augmentative biological control, with the possible use of A. ovatus as food for the mass production and pollen of T. domingensis as a food supplement for this predator in practical field releases.
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Hemípteros , Ácaros/fisiología , Control Biológico de Vectores , Animales , Benin , Brasil , Dieta , Femenino , Hemípteros/crecimiento & desarrollo , Hemípteros/fisiología , Larva/crecimiento & desarrollo , Larva/fisiología , Ácaros/genética , Ácaros/crecimiento & desarrollo , Países Bajos , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Óvulo/crecimiento & desarrollo , Óvulo/fisiologíaRESUMEN
Improving breastfeeding rates is a global goal. To achieve it, actions targeting modifiable factors that influence the breastfeeding experience, such as maternal self-efficacy, could be a promising path, especially with preterm infants' mothers. Considering the current ubiquitous technology, we developed a mobile application for mothers of preterm infants to constitute a breastfeeding information and support platform. The study was developed in three phases: a survey to determine characteristics and preferences of preterm infants' mothers; the app development by an interdisciplinary team, following the principles of Disciplined Agile Delivery; and the face and content validation by 10 professionals. The app contains 80 screens and 11 strategies to address prematurity, lactation, breastfeeding, peer support, maternal emotions, resilience, and motivation. Nurses can apply their expertise by designing mHealth-based interventions, employing scientific evidence, and considering the interests and preferences of the target population. Future studies will assess the user experience, the effect on breastfeeding self-efficacy, and breastfeeding rates, and develop a culturally adapted English version of the app for women in Canada.
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Recien Nacido Prematuro , Aplicaciones Móviles , Lactante , Recién Nacido , Femenino , Humanos , Lactancia Materna/psicología , Autoeficacia , Madres/psicologíaRESUMEN
A new restoration methodology is proposed to enhance mammographic images through the improvement of contrast features and the simultaneous suppression of noise. Denoising is performed in the first step using the Anscombe transformation to convert the signal-dependent quantum noise into an approximately signal-independent Gaussian additive noise. In the Anscombe domain, noise is filtered through an adaptive Wiener filter, whose parameters are obtained by considering local image statistics. In the second step, a filter based on the modulation transfer function of the imaging system in the whole radiation field is applied for image enhancement. This methodology can be used as a preprocessing module for computer-aided detection (CAD) systems to improve the performance of breast cancer screening. A preliminary assessment of the restoration algorithm was performed using synthetic images with different levels of quantum noise. Afterward, we evaluated the effect of the preprocessing on the performance of a previously developed CAD system for clustered microcalcification detection in mammographic images. The results from the synthetic images showed an increase of up to 11.5 dB (p = 0.002) in the peak signal-to-noise ratio. Moreover, the mean structural similarity index increased up to 8.3 % (p < 0.001). Regarding CAD performance, the results suggested that the preprocessing increased the detectability of microcalcifications in mammographic images without increasing the false-positive rates. Receiver operating characteristic analysis revealed an average increase of 14.1 % (p = 0.01) in overall CAD performance when restored image sets were used.
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Artefactos , Enfermedades de la Mama/diagnóstico por imagen , Mamografía/métodos , Interpretación de Imagen Radiográfica Asistida por Computador , Femenino , Humanos , Mamografía/instrumentación , Fantasmas de Imagen , Curva ROC , Intensificación de Imagen Radiográfica/métodos , Sensibilidad y Especificidad , Relación Señal-RuidoRESUMEN
The lifetime risk of developing atrial fibrillation (AF) is 1 in 3 adults, resulting in a prevalence of 2-4%. Rheumatic heart disease (RHD) is a frequent aetiology of valvular heart disease in lowand middle-income countries. Between 21% and 80% of patients with mitral valve disease, especially with stenosis, may have AF. Both these conditions, AF and RHD, present a state of persistent inflammation. In turn, inflammation is a frequent cause of anisocytosis, which can be evidenced through the parameter RDW (red bold cell distribution width). Factors associated with increased RDW are also known as risk factors associated with a higher incidence of AF. RDW may have an independent role in the pathogenesis of AF and the increased propensity of both thromboembolic and bleeding events. Another marker involved in the incidence of AF is the neutrophil-lymphocyte ratio. This is also a marker of oxidative stress and inflammation and is associated with a higher rate of AF recurrence. This review will evaluate these biomarkers and their association with cardiovascular events in patients with AF and RHD. The hypotheses and current debates about the relationship of biomarkers with the severity of chronic valve dysfunction, with acute rheumatic carditis in the paediatric population, and with the presence of thrombus in the left atrium will be discussed.
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Fibrilación Atrial , Enfermedades de las Válvulas Cardíacas , Cardiopatía Reumática , Adulto , Niño , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Cardiopatía Reumática/diagnóstico , Cardiopatía Reumática/epidemiología , Neutrófilos , Enfermedades de las Válvulas Cardíacas/diagnóstico , Enfermedades de las Válvulas Cardíacas/complicaciones , Linfocitos , Biomarcadores , Inflamación/diagnóstico , Inflamación/complicaciones , EritrocitosRESUMEN
Abstract: We present an updated value of the Muonium 1S-2S transition frequency, highlighting contributions from different QED corrections as well as the large uncertainty in the Dirac contribution, stemming from the uncertainty of the electron to muon mass ratio. Improving the measurement of this spectral line would allow to extract a more accurate determination of fundamental constants, such as the electron to muon mass ratio or, combined with the Muonium hyperfine splitting, an independent value of the Rydberg constant. Furthermore, we report on the current status of the Mu-MASS experiment, which aims at measuring the Muonium 1S-2S transition frequency at a 10 kHz uncertainty level.
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Digital mammography is currently the most common imaging tool for breast cancer screening. Although the benefits of using digital mammography for cancer screening outweigh the risks associated with the x-ray exposure, the radiation dose must be kept as low as possible while maintaining the diagnostic utility of the generated images, thus minimizing patient risks. Many studies investigated the feasibility of dose reduction by restoring low-dose images using deep neural networks. In these cases, choosing the appropriate training database and loss function is crucial and impacts the quality of the results. In this work, we used a standard residual network (ResNet) to restore low-dose digital mammography images and evaluated the performance of several loss functions. For training purposes, we extracted 256,000 image patches from a dataset of 400 images of retrospective clinical mammography exams, where dose reduction factors of 75% and 50% were simulated to generate low and standard-dose pairs. We validated the network in a real scenario by using a physical anthropomorphic breast phantom to acquire real low-dose and standard full-dose images in a commercially available mammography system, which were then processed through our trained model. We benchmarked our results against an analytical restoration model for low-dose digital mammography. Objective assessment was performed through the signal-to-noise ratio (SNR) and the mean normalized squared error (MNSE), decomposed into residual noise and bias. Statistical tests revealed that the use of the perceptual loss (PL4) resulted in statistically significant differences when compared to all other loss functions. Additionally, images restored using the PL4 achieved the closest residual noise to the standard dose. On the other hand, perceptual loss PL3, structural similarity index (SSIM) and one of the adversarial losses achieved the lowest bias for both dose reduction factors. The source code of our deep neural network is available at https://github.com/WANG-AXIS/LdDMDenoising.