scholarly journals Correction of Tropical Rainfall Measuring Missions Satellite Data of Solar Radiation for the High Andean Areas of Peru

Author(s):  
Odilon Correa Cuba ◽  
Rosa Gabriela Coral Surco ◽  
Juan José Zuñiga Negron

The spatial and temporal quantification of climatic elements is necessary in different regions of the world, as mitigation policies against climate change in recent years the use of renewable energies has been promoted, with solar radiation being an important element, the objective is to correct Tropical Rainfall Measuring Missions (TRMM) satellite data series of solar radiation with respect to the data observed through an automatic meteorological station for a short period at a point located in the southern Peruvian Andes, we proceeded to process the observed data and download satellite information, making use of From a mathematical model, the correction coefficients of the satellite data were determined; The multiplicative factor model better corrects the satellite information, the Pearson correlation improved from R = 0.65 to R = 0.84 for monthly solar radiation, in the series of satellite data corrected for 37 years, a trend was determined -0.0006 Watt/m2/month.

2020 ◽  
Vol 24 (4) ◽  
pp. 108-118
Author(s):  
A. V. Petraikin ◽  
A. K. Smorchkova ◽  
N. D. Kudryavtsev ◽  
K. A. Sergunova ◽  
Z. R. Artyukova ◽  
...  

Rationale. Quantitative CT (QCT) bone densitometry with asynchronous calibration not require a phantom during the scan procedure. Based on calibration data it converts X-ray density in HU to bone mineral density (BMD). Given the large number of CT studies performed on patients at risk of osteoporosis, there is a need for a hands-on method capable of assessing BMD in a short period of time without tailored software or protocols.Goal. To develop a method for QCT bone densitometry using an PHK (PHantom Kalium), to compare the volume BMD measurements with the QCT data with asynchronous calibration provided by software from a reputable developer.Methods. The studies were performed at 64-slice CT unit with body scanning parameters. The BMD was measured using two techniques: 1) QCT with asynchronous calibration using software from a reputable developer; 2) QCT using a PHK phantom (QCT-PHK). For convert the HU to BMD values, we scanned the PHK phantom and calculate correction factor. Phantom contains “vertebrae” filled with potassium hydrogen phosphate in different concentrations. In both methods, the BMD values measured for LI–II, and sometimes for ThXII, LIII.Results. The study enrolled 65 subjects (11 male and 54 female patients); median age 69.0 years. A comparison of the vertebrae BMD measured by QCT and QCT-PHK revealed a significant linear Pearson correlation r = 0.977 (p < 0.05). The Bland–Altman analysis demonstrated a lack of relationship between the difference in measurements and the average BMD and a systematic BMD; bias of +4.50 mg/ml in QCT vs. QCT-PHK. Differences in the division into groups osteoporosis / osteopenia / norm according to the ACR criteria for the two methods were not significant.Conclusion. The developed asynchronous QCT-PHK method measure BMD comparable to the widely used QCT with asynchronous calibration. This method can be used for opportunistic screening for osteoporosis.


2021 ◽  
Vol 11 (13) ◽  
pp. 5932
Author(s):  
Daniela Luminita Ichim ◽  
Liliana Sachelarie ◽  
Alexandra Burlui

(1) Background: The appearance and progression of carious lesions represent a complex phenomenon of interactions of microbial factors (the action of bacteria on the tooth), of the factors related to the host, to the diet, and to the time factor. Which hasan influence on the rate of microbismof the oral cavity on the installation of carious disease? (2) Methods: In order to correctly assess the cariogenic risk of an individual, it is recommended to perform twoor more tests based on different principles (microbiological, clinical, epidemiological). The representative data series for the investigation were analyzed statistically and by applying the Pearson correlation test considering the coefficient of determination R for all pairs of data series. (3) Results: Salivary tests played animportant role in establishing control sessions, in carrying out prophylactic caries therapy, and establishing prognosis. The existence of a statistical associationwas confirmed between the prevalence of dental caries and the results of salivary tests for the study group. (4) Conclusions: The results of the saliva tests can be used in oral health promotion.


2020 ◽  
Vol 12 (13) ◽  
pp. 2123 ◽  
Author(s):  
Leran Han ◽  
Chunmei Wang ◽  
Tao Yu ◽  
Xingfa Gu ◽  
Qiyue Liu

This paper proposes a combined approach comprising a set of methods for the high-precision mapping of soil moisture in a study area located in Jiangsu Province of China, based on the Chinese C-band synthetic aperture radar data of GF-3 and high spatial-resolution optical data of GF-1, in situ experimental datasets and background knowledge. The study was conducted in three stages: First, in the process of eliminating the effect of vegetation canopy, an empirical vegetation water content model and a water cloud model with localized parameters were developed to obtain the bare soil backscattering coefficient. Second, four commonly used models (advanced integral equation model (AIEM), look-up table (LUT) method, Oh model, and the Dubois model) were coupled to acquire nine soil moisture retrieval maps and algorithms. Finally, a simple and effective optimal solution method was proposed to select and combine the nine algorithms based on classification strategies devised using three types of background knowledge. A comprehensive evaluation was carried out on each soil moisture map in terms of the root-mean-square-error (RMSE), Pearson correlation coefficient (PCC), mean absolute error (MAE), and mean bias (bias). The results show that for the nine individual algorithms, the estimated model constructed using the AIEM (mv1) was significantly more accurate than those constructed using the other models (RMSE = 0.0321 cm³/cm³, MAE = 0.0260 cm³/cm³, and PCC = 0.9115), followed by the Oh model (m_v5) and LUT inversion method under HH polarization (mv2). Compared with the independent algorithms, the optimal solution methods have significant advantages; the soil moisture map obtained using the classification strategy based on the percentage content of clay was the most satisfactory (RMSE = 0.0271 cm³/cm³, MAE = 0.0225 cm³/cm³, and PCC = 0.9364). This combined method could not only effectively integrate the optical and radar satellite data but also couple a variety of commonly used inversion models, and at the same time, background knowledge was introduced into the optimal solution method. Thus, we provide a new method for the high-precision mapping of soil moisture in areas with a complex underlying surface.


2021 ◽  
Author(s):  
Krešimir Ruić ◽  
Jadranka Šepić ◽  
Maja Karlović ◽  
Iva Međugorac

&lt;p&gt;Extreme sea levels are known to hit the Adriatic Sea and to occasionally cause floods that produce severe material damage. Whereas the contribution of longer-period (T &gt; 2 h) sea-level oscillations to the phenomena has been well researched, the contribution of the shorter period (T &lt;&amp;#160;2 h) oscillations is yet to be determined. With this aim, data of 1-min sampling resolution were collected for 20 tide gauges, 10 located at the Italian (north and west) and 10 at the Croatian (east) Adriatic coast. Analyses were done on time series of 3 to 15 years length, with the latest data coming from 2020, and with longer data series available for the Croatian coast. Sea level data were thoroughly checked, and spurious data were removed.&amp;#160;&lt;/p&gt;&lt;p&gt;For each station, extreme sea levels were defined as events during which sea level surpasses its 99.9 percentile value. The contribution of short-period oscillations to extremes was then estimated from corresponding high-frequency (T &lt; 2 h) series. Additionally, for four Croatian tide gauge stations (Rovinj, Bakar, Split, and Dubrovnik), for period of 1956-2004, extreme sea levels were also determined from the hourly sea level time series, with the contribution of short-period oscillations visually estimated from the original tide gauge charts.&amp;#160;&amp;#160;&lt;/p&gt;&lt;p&gt;Spatial and temporal distribution of contribution of short-period sea-level oscillations to the extreme sea level in the Adriatic were estimated. It was shown that short-period sea-level oscillation can significantly contribute to the overall extremes and should be considered when estimating flooding levels.&amp;#160;&lt;/p&gt;


1971 ◽  
Vol 12 ◽  
pp. 413-421 ◽  
Author(s):  
B.G. Marsden

There has long been speculation as to whether comets evolve into asteroidal objects. On the one hand, in the original version of the Oort (1950) hypothesis, the cometary cloud was supposed to have formed initially from the same material that produced the minor planets; and an obvious corollary was that the main physical difference between comets and minor planets would be that the latter had long since lost their icy surfaces on account of persistent exposure to strong solar radiation (Öpik, 1963). However, following a suggestion by Kuiper (1951), it is now quite widely believed that, whereas the terrestrial planets and minor planets condensed in the inner regions of the primordial solar nebula, icy objects such as comets would have formed more naturally in the outer parts, perhaps even beyond the orbit of Neptune (Cameron, 1962; Whipple, 1964a). Furthermore, recent studies of the evolution of the short-period comets indicate that it is not possible to produce the observed orbital distribution from the Oort cloud, even when multiple encounters with Jupiter are considered (Havnes, 1970). We must now seriously entertain the possibility that most of the short-period orbits evolved directly from low-inclination, low-eccentricity orbits with perihelia initially in the region between, say, the orbits of Saturn and Neptune, and that these comets have never been in the traditional cloud at great distances from the Sun.


2020 ◽  
Vol 497 (1) ◽  
pp. L19-L23 ◽  
Author(s):  
John Southworth ◽  
D M Bowman ◽  
A Tkachenko ◽  
K Pavlovski

ABSTRACT V453 Cyg is an eclipsing binary containing 14 and 11 $\, {\rm M}_\odot$ stars in an eccentric short-period orbit. We have discovered β Cep-type pulsations in this system using Transiting Exoplanet Survey Satellite data. We identify seven significant pulsation frequencies, between 2.37 and 10.51 d−1, in the primary star. These include six frequencies that are separated by yet significantly offset from harmonics of the orbital frequency, indicating they are tidally perturbed modes. We have determined the physical properties of the system to high precision: V453 Cyg A is the first β Cep pulsator with a precise mass measurement. The system is a vital tracer of the physical processes that govern the evolution of massive single and binary stars.


2015 ◽  
Vol 27 (6) ◽  
pp. 734-742
Author(s):  
Youngmi Kim ◽  
Kyeongmo Kim ◽  
Shinhye Lee

Purpose: We tested the reliability and validity of the Self-Efficacy Questionnaire for Children (SEQ-C) in a sample of children living in orphanages in South Korea. Methods: Our study sample consisted of 334 children aged 13–18 obtained using a convenience sampling method. We conducted a confirmatory factor analysis to identify the factor structure of the 24 self-efficacy items and used a Pearson correlation to explore the scale’s validity. Results: The findings show the SEQ-C is a reliable scale with a three-factor model measuring social, academic, and emotional self-efficacy. Construct validity was also supported by finding a significant negative correlation between self-efficacy and depression. Conclusions: Our study informs social workers and researchers that the SEQ-C measure is a useful tool for practical evaluation and intervention that can be used for children with disadvantaged socioeconomic backgrounds in South Korea.


2014 ◽  
Vol 26 (1) ◽  
pp. 168
Author(s):  
H. W. Vivanco-Mackie ◽  
M. D. Ponce Salazar ◽  
M. M. Gonzales ◽  
M. A. Tapia

Alpacas are induced ovulators, responding to copulation and (or) exogenous application of ovulation-inducing hormones. The objective of this study was to determine the efficiency of the injection of a gonadotropin-releasing hormone (GnRH) agonist versus LH in the induction of ovulation and the presence and size of non-ovulated follicles at the time of embryo collection and its relationship to the yield of transferable embryos in superovulated alpacas. Twenty-one adult (3 to 7 years old) female alpacas under extensive grazing at 4300 m elevation in the Peruvian Andes that had been synchronized and treated for superovulation were induced to ovulate 6 days after the application of the superovulatory hormone (1000 IU of eCG, Folligon®, Intervet International BV, Boxmeer, the Netherlands) by mating with fertile males and injection immediately after copulation of either an IM dose of 0.0084 mg of buserelin acetate (Buserelina Zoovet®, Laboratorio Zoovet, Santa Fe, Argentina) to 10 alpacas (T1) or an IM dose of 5-mg Armour standard of LH (Lutropin®, Bioniche Animal Health, Belleville, ON, Canada) to 11 alpacas (T2). All alpacas had a second mating 12 h after the first mating and were subjected to ovarian inspection by ultrasonography and previous embryo collection by nonsurgical transcervical embryo flushing 6.5 days after the first mating. On average, the embryo recovery rate for T1 was 34.6% and there were 7.8 ± 3.99 corpora lutea (CL), 2.7 ± 4.08 collected embryos, and 3.6 ± 2.95 total, 0.5 ± 0.85 small (<6 mm), 1.8 ± 1.99 medium (≥6 but ≤14 mm), and 1.3 ± 2.11 large (≥15 mm) non-ovulated follicles. For T2, the embryo recovery rate was 59.4% and there were 6.73 ± 1.49 CL, 4.0 ± 2.57 collected embryos, and 0.64 ± 0.81 total, 0.0 ± 0.0 small, 0.36 ± 0.67 medium, and 0.27 ± 0.47 large non-ovulated follicles. The differences between treatments were nonsignificant (P > 0.05) for all the parameters; however, there was a clear tendency for a better recovery rate, more embryos collected, and lower number of non-ovulated follicles in T2. The Pearson correlation coefficient between the presence of large follicles in the ovaries at the time of embryo collection and the total number of embryos collected was negative (r = –0.26) and highly significant (P ≤ 0.001). The use of LH for ovulation induction of superovulated alpacas seems to be more advisable than the use of GnRH agonist; further comparisons with larger number of observations per treatment are recommended. This study was financed by the Peruvian Fund for Innovation, Science and Technology (FINCYT).


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