The calculation of specular reflections on a sphere is a common problem in the Geosciences in general and in Earth remote sensing in particular. Especially in Global Navigation Satellite System ...Reflectometry (GNSS-R), the interferometric or reflection-minus-direct radio propagation delay should be calculated to retrieve sea level in GNSS-R altimetry. However, the solution is not trivial, as can be attested by multiple algorithms reported in the literature, many reinvented independently, without the emergence of a preferred or standard algorithm. We propose their assessment and validation based on special boundary cases, at the spherical horizon and at the vertical direction (zenith), where independent closed-form trigonometric expressions exist. We implemented five different algorithms to compute spherical specular reflection points, including three analytical ones based on a quartic polynomial and two iterative methods. We also computed derived parameters, such as interferometric delay, grazing angle, slant distance, and arc length. We performed simulations for all algorithms considering one hundred different antenna heights above the surface, between 10 m and 1 km. Finally, we compared analytical and iterative algorithms results with truth values at the special boundary cases. On the horizon, we found that all algorithms presented negligible root-mean-square error (RMSE) only for interferometric delay, but all other parameters exhibited varying accuracies for each algorithm. The iterative methods had the worst results at the spherical horizon, reaching meter-level RMSE for reflection point position and slant distance, whereas Miller & Vegh algorithm had worst results at zenith, especially in terms of grazing angle, position coordinate and arc length. We found the algorithm of Fujimura et al. to be the most stable and accurate. We performed a relative intercomparison between Fujimura et al. and each other algorithms at 45° as an intermediary case. We confirmed Fermat's iterative algorithm had the worst performance. The algorithms of Martín-Neira and Helm exhibited a systematic effect on certain parameters, proportional to antenna height and inversely proportional to satellite elevation. Therefore, Fujimura et al. is the recommended algorithm to compute specular reflections on a sphere.
•Computing specular reflections on a sphere is a common problem in the geosciences.•Analytical and iterative algorithms exist, but no standard formulation has emerged.•We develop special boundary cases to provide truth values for the assessment of algorithms.•Analytical formulations had near exact results while iterative methods were approximate.•We recommend Fujimura et al.‘s algorithm based on a complex quartic polynomial.
All methods for estimating evapotranspiration (
ET
o
) require accurate and complete meteorological datasets. However, the common lack of such datasets in Brazil, as well as the definition of the ...method that best represents the spatiotemporal pattern of
ET
o
, are the main challenges to assess and mitigate the effects of climate variability (natural or due to anthropogenic climate change) in the Brazilian agricultural production systems. In this sense, this work aims to assess the spatiotemporal pattern of
ET
o
, identify, and select among twenty-nine methods the one that presents the best performance in estimating
ET
o
for different regions of Brazil using a high-resolution gridded weather dataset (
GWD
). In this study, performance is evaluated by comparing the
ET
o
results obtained through the different methods to that estimated by the Penman–Monteith method. The weather variables used were near surface air temperature (maximum and minimum), relative humidity, wind speed at 2 m, global solar radiation,
ET
o
, and sea level pressure in a daily basis from 1980 to 2017. Through principal component analysis (PCA), the behavior of
ET
o
was mainly influenced by the global solar radiation, maximum air temperature, and relative humidity. For this reason, the performance of the methods varied across the Brazilian regions and seasons. The
Turc
and
Abtew
methods showed the best performance in estimating daily
ET
o
, with lower
RMSE
(~ 0.5 mm day
−1
) and
MAPE
(~ 12%) and higher
c-index
values (~ 0.75), with slight advantage of
Turc
method, for all Brazilian regions and seasons. Also, the
ET
o
estimation by
Turc
and
Abtew
using the
GWD
dataset showed a good agreement with Penman–Monteith method. Finally, the Hargreaves, Penman Original, and Stephens Stewart methods stood out for the Brazilian Northeast region (mean
RMSE
of 0.7 mm day
−1
, mean
MAPE
of 14%, mean
c-index
of 0.7), in areas that presents predominantly arid and semiarid climate conditions.
In this study, we examined whether experience level and various dual motor and cognitive or single tasks influenced young soccer players’ physical performance during small-sided games. Participants ...were 72 players from U-13 (n = 36) and U-17 (n = 36) groups who participated in 3-to-a-side small-sided games under four experimental conditions: control, a secondary motor task, an additional related secondary cognitive task, and an additional secondary non-specific task. We used GPS devices to measure physical performance in terms of distances covered and accelerations at different thresholds. We found no significant interaction effect between player experience and task condition (p = .540), meaning that dual tasks had comparable effects on players of different experience levels. There were significant main effects of both experience level (p < .001) and condition (p < .001) on most physically related variables. Older players outperformed younger ones, particularly in high-intensity actions. While secondary motor tasks decreased physical performance, secondary cognitive tasks, irrespective of specificity, did not impair players’ performances. In conclusion, experience level did not influence the players’ physical response to dual tasks, and a secondary motor task was more disruptive to physical performance than either of two types of secondary cognitive tasks. Cognitive tasks can be incorporated into soccer training without compromising physical performance.
Background
We assessed whether COVID‐19 is associated with de novo pain and de novo chronic pain (CP).
Methods
This controlled cross‐sectional study was based on phone interviews of patients ...discharged from hospital after COVID‐19 compared to the control group composed of individuals hospitalized during the same period due to non‐COVID‐19 causes. Patients were classified as having previous CP based on the ICD‐11/IASP criteria, de novo pain (i.e. any new type of pain, irrespective of the pain status before hospital stay), and de novo CP (i.e. persistent or recurring de novo pain, lasting more than 3 months) after COVID‐19. We assessed pain prevalence and its characteristics, including headache profile, pain location, intensity, interference, and its relationship with fatigue, and persistent anosmia. Forty‐six COVID‐19 and 73 control patients were included. Both groups had similar sociodemographic characteristics and past medical history.
Results
Length of in‐hospital‐stay and ICU admission rates were significantly higher amongst COVID‐19 survivours, while mechanical ventilation requirement was similar between groups. Pre‐hospitalisation pain was lower in COVID‐19 compared to control group (10.9% vs. 42.5%; p = 0.001). However, the COVID‐19 group had a significantly higher prevalence of de novo pain (65.2% vs. 11.0%, p = 0.001), as well as more de novo headache (39.1%) compared to controls (2.7%, p = 0.001). New‐onset CP was 19.6% in COVID‐19 patients and 1.4% (p = 0.002) in controls. These differences remained significant (p = 0.001) even after analysing exclusively (COVID: n = 40; controls: n = 34) patients who did not report previous pain before the hospital stay. No statistically significant differences were found for mean new‐onset pain intensity and interference with daily activities between both groups. COVID‐19 pain was more frequently located in the head/neck and lower limbs (p < 0.05). New‐onset fatigue was more common in COVID‐19 survivours necessitating inpatient hospital care (66.8%) compared to controls (2.5%, p = 0.001). COVID‐19 patients who reported anosmia had more new‐onset pain (83.3%) compared to those who did not (48.0%, p = 0.024).
Conclusion
COVID‐19 was associated with a significantly higher prevalence of de novo CP, chronic daily headache, and new‐onset pain in general, which was associated with persistent anosmia.
Significance
There exists de novo pain in a substantial number of COVID‐19 survivours, and some develop chronic pain. New‐onset pain after the infection was more common in patients who reported anosmia after hospital discharge.
Testicular heat stress affects sperm quality and fertility. However, the chronology of these effects is not yet fully understood. This study aimed to establish the early sequential effects of heat ...stress in bull sperm quality. Semen and blood samples of Nellore breed bulls were collected and distributed into control and testicular heat stress (scrotal bags/96 h) groups. Semen samples were evaluated for sperm motility, abnormalities, plasma membrane integrity, acrosomal membrane integrity, mitochondrial membrane potential, sperm lipid peroxidation, seminal plasma lipid peroxidation, and DNA fragmentation. Blood plasma was also evaluated for lipid peroxidation. An increase in sperm abnormalities was observed 7 days following heat stress. After 14 days, sperm lipid peroxidation increased and mitochondrial membrane function, sperm motility, and plasma membrane integrity decreased. Heat stress effects were still observed after 21 days following heat stress. An increase in sperm DNA fragmentation was observed as a late effect after 28 days. Thus, the initial effects of heat stress (i.e., increasing sperm abnormalities and lipid peroxidation) suggest the presence of oxidative stress in the semen that alters mitochondrial function, sperm motility, plasma membrane integrity, and belatedly, DNA fragmentation. Although sperm abnormalities persisted and increased over time, sperm lipid peroxidation, in turn, increased only until 21 days after heat stress. In this regard, these findings provide a greater understanding of the chronological effects of experimentally induced heat stress on bovine sperm, providing valuable insights about spermatogenesis during the first 28 days following heat stress.
Aim: The diversity of reproductive modes among amphibians constitutes a striking example of how differences in the biology of species provide important explanations for species distribution patterns ...on a broad scale. We hypothesize that sites with a higher humidity level will support more modes of reproduction than drier sites and will consequently exhibit a higher phylogenetic diversity. Furthermore, if there is a gradient in the tolerance of reproductive modes to desiccation, there will be a nested pattern in the composition of reproductive modes among sites. Location: Twenty-seven forest sites in the Brazilian Atlantic Forest. Methods: Through a path analysis approach, we evaluated the direct and indirect effects of the humidity level on the number of reproductive modes, as well as the relative importance of both variables on amphibian phylogenetic diversity. A nestedness analysis was used to quantify the extent to which the compositions of both species and reproductive modes in drier sites correspond to subsets of those in sites with higher annual precipitation. Results: We found that the reproductive modes present in drier sites are nonrandom subsets of those present in sites with higher humidity levels. Because reproductive modes are phylogenetically conserved among amphibians, sites with a greater number of reproductive modes supported greater phylogenetic diversity. Sites with high precipitation throughout the year provided suitable environmental conditions for a larger number of reproductive modes, whereas sites with low precipitation and typical seasonal climates supported only those reproductive modes specialized to resist desiccation. Main conclusions: Our results show that humidity-related variables are key environmental factors related to both the richness of reproductive modes and phylogenetic diversity. Our results support the hypothesis that the higher phylogenetic diversity found in moister sites reflects differences in the tolerance to desiccation among different reproductive modes. Given that reproductive modes are associated with susceptibility to desiccation, their incorporation into explanatory models may trigger a significant advance in the understanding of the mechanisms regulating the species richness and composition of amphibian communities.
Scrotal heat stress affects spermatogenesis and impairs male fertility by increasing sperm morphological abnormalities, oxidative stress and DNA fragmentation. While sperm morpho-functional changes ...triggered by scrotal heat stress are well described, sperm molecular alterations remain unknown. Recently, spermatozoa were described as accumulating miRNAs during the last steps of spermatogenesis and through epididymis transit, mainly by communication with small extracellular vesicles (sEVs). Herein, the aim was to investigate the impact of scrotal heat stress in miRNAs profile of sperm, as well as, seminal plasma sEVs. Six Nelore bulls (Bos indicus) were divided into two groups: Control (CON; n = 3) and Scrotal Heat Stress (SHS; n = 3; scrotal heat stressed during 96 h by scrotal bags). The day that the scrotal bags were removed from SHS group was considered as D0 (Day zero). Seminal plasma sEVs were isolated from semen samples collected seven days after heat stress (D+7) to evaluate sEVs diameter, concentration, and 380 miRNA levels. Sperm morpho-functional features and profile of 380 miRNAs were evaluated from semen collected 21 days after heat stress (D+21). As a control, sEVs and sperm were analyzed seven days before heat stress (D-7). Only semen parameters that were not significantly different (P > 0.05) among bulls on D-7 were addressed on D+7 and D+21. While no alterations in diameter and concentration were detected in sEVs on D+7 between CON and SHS groups, three sEVs-miRNAs (miR-23b-5p, −489 and −1248) were down-regulated in SHS bulls compared to CON on D+7; other three (miR-126-5p, −656 and −1307) displayed a tendency (0.05 < P < 0.10) to be altered. Sperm oxidative stress was higher, and the level of 21 sperm miRNAs was altered (18 down-, 3 up-regulated) in SHS bulls compared to CON on D+21. Functional analysis indicated that target genes involved in transcription activation, as well as cell proliferation and differentiation were related to the 18 down-regulated sperm miRNAs (miR-9-5p, −15a, −18a, −20b, −30a-5p, −30b-5p, −30d, −30e-5p −34b, −34c, −106b, -126-5p, −146a, −191, −192, −200b, −335 and −449a). Thus, the scrotal heat stress probably impacted testicular and epididymis functions by reducing the levels of a substantial proportion of sEVs and sperm miRNAs. Our findings suggest that miR-126-5p was possibly trafficked between sEVs and sperm and provide new insights on the mechanism by which sperm acquire miRNAs in the last stages of spermatogenesis and sperm maturation in cattle.
•Scrotal heat stress (SHS) mainly down-regulates sperm miRNA levels.•SHS changes sEVs-associated-miRNAs involved in cell biosynthesis processes.•SHS changes miR-126-5p level in sperm and small extracellular vesicles.•miR-15a, −34b, −34c, −146a, −200b and −449a are potential spermatogenesis modulators.
In certain clinical situations, root canal treatment in teeth with apical periodontitis is performed in multiple visits, with the use of intracanal dressing between visits, aiming to reduce ...microorganisms and their by-products of the root canal system prior to filling. However, in recent years, discussions have been growing about the real need for the use of intracanal dressing in these cases. The use of ultrasonic activation of the auxiliary chemical substance has increased the potential for decontamination promoted during the chemomechanical preparation of the root canal. Thus, this study is designed to explore whether the use of intracanal dressing between visits during endodontic treatment favors periradicular repair in teeth with apical periodontitis.
This is a randomized, prospective, double-blinded, controlled clinical trial designed to evaluate 3 distinct clinical approaches used during endodontic therapy: group 1-root canal treatment in a single visit (RCT-SV); group 2-root canal treatment in two visits with intracanal dressing (RCT-TVWD); and group 3-root canal treatment in two visits without intracanal dressing (RCT-TVWOD). A total of 150 adult patients aged 18 to 60, with at least one tooth diagnosed with asymptomatic apical periodontitis and periradicular lesion (confirmed with a cone beam computed tomography (CBCT)), will be randomized and will undergo one of the types of clinical approaches during endodontic therapy. Patients' postoperative pain levels will also be recorded in periods of 24, 48, and 72 h and 7 days. Subsequently, clinical findings and long-term follow-up evaluations, with periradicular repair, will be performed at 6 and 12 months by intraoral periapical radiograph (IOPAR) and CBCT at the 24-month follow-up.
This study will evaluate the periradicular repair of mandibular molar teeth with apical periodontitis, providing information about the efficacy, benefits, and safety of performing the endodontic treatment in a single and two visits, with and without the use of calcium hydroxide dressing. All endodontic therapy procedures will be performed under a dental operating microscope and using ultrasonic activation of auxiliary chemical substances. These results may contribute to changes in the clinical approaches adopted during endodontic therapy of teeth with apical periodontitis and reveal the potential of complementary approaches that aim to enhance the decontamination of the root canal system during the preparation stage.
ClinicalTrials.gov NCT05256667. Registered on 24 February 2022.
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Propolis, is a bee product collected from exudates and flower buds of several plants, has strong aroma and several biological applications. This study aimed at evaluating the chemical ...composition and in vitro antioxidant, antibacterial and cytotoxic properties of volatile oil from Brazilian brown propolis. It was extracted by hydrodistillation and analyzed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. Volatile oil from brown propolis exhibited strong antibacterial activity against H. pylori (MIC 3.25μg/ml), Mycobacterium tuberculosis (MIC 50μg/ml) and M. avium (MIC 62.5μg/ml). It was evaluated in vitro for antioxidant activity by DPPH (IC50 25.0μg/ml) and ABTS (IC50 30.1μg/ml) methods. Its cytotoxic property was evaluated in normal (human fibroblasts, GM07429A) and tumor (MCF-7-human breast adenocarcinoma; HeLa-human cervical adenocarcinoma and M059J-human glioblastoma) cell lines. IC50 values were 81.32 μg/ml for GM07429A and 85.00, 129.40 and 84.12 μg/ml for MCF-7, HeLa and M059J cells, respectively. Three major dereplicated components of volatile oil from brown propolis were acetophenone (15.2%), nerolidol (13.3%), and spathulenol (11.6%). Our results contribute to a better understanding of the chemical and biological properties of Brazilian brown propolis and provide evidence for its potential medicinal use.
Overexpression of human epidermal growth factor receptor-2 (HER-2) occurs in 20% of all breast cancer subtypes, especially those that present the worst prognostic outcome through a very invasive and ...aggressive tumour. HCC-1954 (HER-2+) is a highly invasive, metastatic cell line, whereas MCF-7 is mildly aggressive and non-invasive. We investigated membrane proteins from both cell lines that could have a pivotal biological significance in metastasis. Membrane protein enrichment for HCC-1954 and MCF-7 proteomic analysis was performed. The samples were analysed and quantified by mass spectrometry. High abundance membrane proteins were confirmed by Western blot, immunofluorescence, and flow cytometry. Protein interaction prediction and correlations with the Cancer Genome Atlas (TCGA) patient data were conducted by bioinformatic analysis. In addition, β1 integrin expression was analysed by Western blot in cells upon trastuzumab treatment. The comparison between HCC-1954 and MCF-7 membrane-enriched proteins revealed that proteins involved in cytoskeleton organisation, such as HER-2, αv and β1 integrins, E-cadherin, and CD166 were more abundant in HCC-1954. β1 integrin membrane expression was higher in the HCC-1954 cell line resistant after trastuzumab treatment. TCGA data analysis showed a trend toward a positive correlation between HER-2 and β1 integrin in HER-2+ breast cancer patients. Differences in protein profile and abundance reflected distinctive capabilities for aggressiveness and invasiveness between HCC-1954 and MCF-7 cell line phenotypes. The higher membrane β1 integrin expression after trastuzumab treatment in the HCC-1954 cell line emphasised the need for investigating the contribution of β1 integrin modulation and its effect on the mechanism of trastuzumab resistance.
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