scholarly journals Cardiorespiratory Coordination in Hypercapnic Test Before and After High-Altitude Expedition

2021 ◽  
Vol 12 ◽  
Author(s):  
Valentina V. Gultyaeva ◽  
Dmitriy Y. Uryumtsev ◽  
Margarita I. Zinchenko ◽  
Vladimir N. Melnikov ◽  
Natalia V. Balioz ◽  
...  

Coordination of cardiovascular and respiratory systems enables a wide range of human adaptation and depends upon the functional state of an individual organism. Hypoxia is known to elicit changes in oxygen and carbon dioxide sensitivity, while training alters cardiorespiratory coordination (CRC). The delayed effect of high altitude (HA) acclimatization on CRC in mountaineers remains unknown. The objective of this study was to compare CRC in acute hypercapnia in mountaineers before and after a HA expedition. Nine trained male mountaineers were investigated at sea level before (Pre-HA) and after a 20-day sojourn at altitudes of 4,000–7,000 m (Post-HA) in three states (Baseline, Hypercapnic Rebreathing, and Recovery). A principal component (PC) analysis was performed to evaluate the CRC. The number of mountaineers with one PC increased Post-HA (nine out of nine), compared to Pre-HA (five out of nine) [Chi-square (df = 1) = 5.14, P = 0.023]; the percentage of total variance explained by PC1 increased [Pre-HA median 65.6 (Q1 64.9/Q3 74.9), Post-HA 75.6 (73.3/77.9), P = 0.028]. Post-HA, the loadings of the expired fraction of O2, CO2, and ventilation onto PC1 did not change, and the loading of heart rate increased [Pre-HA 0.64 (0.45/0.68) and Post-HA 0.76 (0.65/0.82), P = 0.038]. During the Recovery, the percentage of total variance explained by PC1 was higher than during the Baseline. Post-HA, there was a high correlation between the Exercise addiction scores and the eigenvalues of PC1 (r = 0.9, P = 0.001). Thus, acute hypercapnic exposure reveals the Post-HA increase in cardiorespiratory coordination, which is highly related to the level of exercise addiction.

2022 ◽  
Vol 12 (2) ◽  
pp. 12
Author(s):  
Murad M. Al-Shboul

The purpose of this study was to validate one of the most frequently used tools for assessing anxiety associated with foreign languages. The researcher translated it into Arabic because there was no Arabic literature on such an instrument. To achieve the goal, a committee approach was followed (Brislin, 1980) to ensure the validity of the translation. A sample of 102 students was purposefully selected from International Islamic University Malaysia. The instrument consists of 33 items to measure communication apprehension, test anxiety, and fear of negative evaluation. A Principal Component Analysis (PCA) was run to validate the instrument; initially, the PCA produced ten-factor solutions, accounting for 71% of the total variance explained. However, the last nine factors had only two or three loadings each, and they had cross-loading as well. Therefore, only one factor was used in the final, which accounted for 51% of the total variance. The researcher took this factor due to its importance for the Arabic literature, which is also in need of a valid instrument to measure communication apprehension. Due to the lack of convergent validity in the other items, the researcher suggests validating the original instrument.


Nutrients ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1155 ◽  
Author(s):  
Livia Dickson ◽  
Mathieu Tenon ◽  
Ljubica Svilar ◽  
Pascale Fança-Berthon ◽  
Raphael Lugan ◽  
...  

Genipap (Genipa americana L.) is a native fruit from Amazonia that contains bioactive compounds with a wide range of bioactivities. However, the response to genipap juice ingestion in the human exposome has never been studied. To identify biomarkers of genipap exposure, the untargeted metabolomics approach in human urine was applied. Urine samples from 16 healthy male volunteers, before and after drinking genipap juice, were analyzed by liquid chromatography–high-resolution mass spectrometry. XCMS package was used for data processing in the R environment and t-tests were applied on log-transformed and Pareto-scaled data to select the significant metabolites. The principal component analysis (PCA) score plots showed a clear distinction between experimental groups. Thirty-three metabolites were putatively annotated and the most discriminant were mainly related to the metabolic pathways of iridoids and phenolic derivatives. For the first time, the bioavailability of genipap iridoids after human consumption is reported. Dihydroxyhydrocinnamic acid, (1R,6R)-6-hydroxy-2-succinylcyclohexa-2,4-diene-1-carboxylate, hydroxyhydrocinnamic acid, genipic acid, 12-demethylated-8-hydroxygenipinic acid, 3(7)-dehydrogenipinic acid, genipic acid glucuronide, nonate, and 3,4-dihydroxyphenylacetate may be considered biomarkers of genipap consumption. Human exposure to genipap reveals the production of derivative forms of bioactive compounds such as genipic and genipinic acid. These findings suggest that genipap consumption triggers effects on metabolic signatures.


2020 ◽  
Author(s):  
jean-michel ars ◽  
Pascal Tarits ◽  
Sophie Hautot ◽  
Mathieu Bellanger ◽  
Olivier Coutant

<p>Geophysical exploration of natural resources is challenging because of complex and/or narrow geological structures to image. Geophysical models should provide an image at a scale large enough to understand the complex geology but with the adequate resolution to resolve features like faults. One solution to overcome this difficulty is to integrate large multiphysics datasets to provide complementary insight of the geology. New approaches involve joint inversion of all datasets in a common process where models are coupled together. Geometrical or quantitative interpretation of the joint models image several physical properties shaping the same pattern of the target resources. In reality, models resulting from joint inversion are still challenging to interprete. Most of the joint inversion techniques are based on parameters relationship or geometrical constraint which imply common interfaces between models. This assumption may be wrong since geophysical methods have different sensitivity to the same geological object.</p><p>Geophysical integration cover a wide range of approach from the visual interpretation of model presented side by side to sophistical statistical analyses such as automatic clustering. We present here a geophysical models integration based on principal component analysis (PCA). PCA allow to gain insight on a multi-variable system with high level of interaction. PCA aims to reorganize the system by finding a new set of variables distributed along new orthogonal axis and keeping most of the variance from the data. Thus geophysical interaction are highlighted along components that can be interpreted in terms of patterns. We applied this integration method to gravity, ambient noise tomography and resistivity models obtained from joint inversion in the framework of unconventional geothermal exploration in Massif Central, France. PCA of the log-resistivity, the density contrast and the Vs velocity model has 3 independent components. The first one (PC1) representing 69% of the total variance of the system is highly influenced by the parameter coupling enforced in the joint inversion process. PC1 allows to point to geophysical structures that may be related to the geothermal system. The second component (PC2) represents 22% of the total variance and is strongly correlated to the resistivity distribution The correlation with the surface geology suggests that it may be a fault marker. The third component (PC1: 9% of the total variance) is still above the nul hypothesis and seems to describe the 3D geometry of the geological units. This statistical approach may help the geophysical interpretation into a possible geothermal conceptual model</p><p> </p>


2020 ◽  
Author(s):  
Luis Anunciacao ◽  
janet squires ◽  
J. Landeira-Fernandez

One of the main activities in psychometrics is to analyze the internal structure of a test. Multivariate statistical methods, including Exploratory Factor analysis (EFA) and Principal Component Analysis (PCA) are frequently used to do this, but the growth of Network Analysis (NA) places this method as a promising candidate. The results obtained by these methods are of valuable interest, as they not only produce evidence to explore if the test is measuring its intended construct, but also to deal with the substantive theory that motivated the test development. However, these different statistical methods come up with different answers, providing the basis for different analytical and theoretical strategies when one needs to choose a solution. In this study, we took advantage of a large volume of published data (n = 22,331) obtained by the Ages and Stages Questionnaire Social-Emotional (ASQ:SE), and formed a subset of 500 children to present and discuss alternative psychometric solutions to its internal structure, and also to its subjacent theory. The analyses were based on a polychoric matrix, the number of factors to retain followed several well-known rules of thumb, and a wide range of exploratory methods was fitted to the data, including EFA, PCA, and NA. The statistical outcomes were divergent, varying from 1 to 6 domains, allowing a flexible interpretation of the results. We argue that the use of statistical methods in the absence of a well-grounded psychological theory has limited applications, despite its appeal. All data and codes are available at https://osf.io/z6gwv/.


1990 ◽  
Vol 55 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Drahomír Hnyk

The principal component analysis has been applied to a data matrix formed by 7 usual substituent constants for 38 substituents. Three factors are able to explain 99.4% cumulative proportion of total variance. Several rotations have been carried out for the first two factors in order to obtain their physical meaning. The first factor is related to the resonance effect, whereas the second one expresses the inductive effect, and both together describe 97.5% cumulative proportion of total variance. Their mutual orthogonality does not directly follow from the rotations carried out. With the help of these factors the substituents are divided into four main classes, and some of them assume a special position.


2021 ◽  
pp. 074880682198989
Author(s):  
Alix Ferdinand ◽  
Suzan Obagi

The interest in cosmetic procedures for patients with skin of color is on an upward trend. Globally, dyschromia and hyperpigmentation remain the most common disorders for which patients seek treatment. The goals of a perioperative skin conditioning program include allowing a broad range of patients to be treated regardless of skin phototypes, maximizing results, and reducing risk of complications such as post-inflammatory hyperpigmentation and managing post-inflammatory hyperpigmentation if it occurs. The purpose of this article is to highlight common pigmentation concerns among patients with skin of color, the topical agents used to combat these concerns, and a practical approach to creating an effective yet straightforward topical skin care regimen that can be used across a wide range of patient skin phototypes. Before and after photos of patients with a variety of pigmentation concerns are presented along with a description of the treatment regimen used to improve their conditions and to get their skin to a safer state prior to performing any office-based procedures. By understanding the main concerns of patients with skin of color, one can use a simple and effective skincare regimen to allow these patients to be more safely treated. An effective skincare regimen both prepares the skin prior to procedures and postoperatively to help minimize dyschromias in the postoperative phase.


Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 680
Author(s):  
Thuy T. P. Mai ◽  
Craig M. Hardner ◽  
Mobashwer M. Alam ◽  
Robert J. Henry ◽  
Bruce L. Topp

Macadamia is a recently domesticated Australian native nut crop, and a large proportion of its wild germplasm is unexploited. Aiming to explore the existing diversity, 247 wild accessions from four species and inter-specific hybrids were phenotyped. A wide range of variation was found in growth and nut traits. Broad-sense heritability of traits were moderate (0.43–0.64), which suggested that both genetic and environmental factors are equally important for the variability of the traits. Correlations among the growth traits were significantly positive (0.49–0.76). There were significant positive correlations among the nut traits except for kernel recovery. The association between kernel recovery and shell thickness was highly significant and negative. Principal component analysis of the traits separated representative species groups. Accessions from Macadamia integrifolia Maiden and Betche, M. tetraphylla L.A.S. Johnson, and admixtures were clustered into one group and those of M. ternifolia F. Muell were separated into another group. In both M. integrifolia and M. tetraphylla groups, variation within site was greater than across sites, which suggested that the conservation strategies should concentrate on increased sampling within sites to capture wide genetic diversity. This study provides a background on the utilisation of wild germplasm as a genetic resource to be used in breeding programs and the direction for gene pool conservation.


2020 ◽  
Vol 10 (1) ◽  
pp. 30
Author(s):  
Slmaro Park ◽  
Han-Sung Jung ◽  
Young-Soo Jung ◽  
Woong Nam ◽  
Jung Yul Cha ◽  
...  

Decompression followed by enucleation, which is one of the treatments used for odontogenic keratocysts (OKCs), is frequently used in OKC lesions of large sizes. This method offers the advantage of minimizing the possibility of sensory impairment without creating a wide-range bone defect; moreover, the recurrence rate can be significantly lower than following simple enucleation. This study aimed to assess the changes in histology and expression of proliferation markers in OKCs before and after decompression treatment. A total of 38 OKC tissue samples from 19 patients who had undergone decompression therapy were examined morphologically and immunohistochemically to observe changes in proliferative activity before and after decompression. The markers used for immunohistochemistry (IHC) staining were Bcl-2, epidermal growth factor receptor (EGFR), Ki-67, P53, PCNA, and SMO. The immunohistochemistry positivity of the 6 markers was scored by using software ImageJ, version 1.49, by quantifying the intensity and internal density of IHC-stained epithelium. The values of Bcl-2, Ki-67, P53, proliferating cell nuclear antigen (PCNA), and SMO in OKCs before and after decompression showed no significant change. No correlation between clinical shrinkage and morphologic changes or expression of proliferation and growth markers could be found. There was no statistical evidence that decompression treatment reduces potentially aggressive behavior of OKC within the epithelial cyst lining itself. This might indicate that decompression does not change the biological behavior of the epithelial cyst lining or the recurrence rate.


2021 ◽  
Vol 11 (4) ◽  
pp. 1431
Author(s):  
Sungsik Wang ◽  
Tae Heung Lim ◽  
Kyoungsoo Oh ◽  
Chulhun Seo ◽  
Hosung Choo

This article proposes a method for the prediction of wide range two-dimensional refractivity for synthetic aperture radar (SAR) applications, using an inverse distance weighted (IDW) interpolation of high-altitude radio refractivity data from multiple meteorological observatories. The radio refractivity is extracted from an atmospheric data set of twenty meteorological observatories around the Korean Peninsula along a given altitude. Then, from the sparse refractive data, the two-dimensional regional radio refractivity of the entire Korean Peninsula is derived using the IDW interpolation, in consideration of the curvature of the Earth. The refractivities of the four seasons in 2019 are derived at the locations of seven meteorological observatories within the Korean Peninsula, using the refractivity data from the other nineteen observatories. The atmospheric refractivities on 15 February 2019 are then evaluated across the entire Korean Peninsula, using the atmospheric data collected from the twenty meteorological observatories. We found that the proposed IDW interpolation has the lowest average, the lowest average root-mean-square error (RMSE) of ∇M (gradient of M), and more continuous results than other methods. To compare the resulting IDW refractivity interpolation for airborne SAR applications, all the propagation path losses across Pohang and Heuksando are obtained using the standard atmospheric condition of ∇M = 118 and the observation-based interpolated atmospheric conditions on 15 February 2019. On the terrain surface ranging from 90 km to 190 km, the average path losses in the standard and derived conditions are 179.7 dB and 182.1 dB, respectively. Finally, based on the air-to-ground scenario in the SAR application, two-dimensional illuminated field intensities on the terrain surface are illustrated.


Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1879
Author(s):  
Oladipupo Q. Adiamo ◽  
Yasmina Sultanbawa ◽  
Daniel Cozzolino

In recent times, the popularity of adding value to under-utilized legumes have increased to enhance their use for human consumption. Acacia seed (AS) is an underutilized legume with over 40 edible species found in Australia. The study aimed to qualitatively characterize the chemical composition of 14 common edible AS species from 27 regions in Australia using mid-infrared (MIR) spectroscopy as a rapid tool. Raw and roasted (180 °C, 5, 7, and 9 min) AS flour were analysed using MIR spectroscopy. The wavenumbers (1045 cm−1, 1641 cm−1, and 2852–2926 cm−1) in the MIR spectra show the main components in the AS samples. Principal component analysis (PCA) of the MIR data displayed the clustering of samples according to species and roasting treatment. However, regional differences within the same AS species have less of an effect on the components, as shown in the PCA plot. Statistical analysis of absorbance at specific wavenumbers showed that roasting significantly (p < 0.05) reduced the compositions of some of the AS species. The results provided a foundation for hypothesizing the compositional similarity and/or differences among AS species before and after roasting.


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