An analysis of the sunspot observations made by Hevelius during 1642-1645 is presented. These records are the only systematic sunspot observations just before the Maunder Minimum (MM). We have ...studied different phenomena meticulously recorded by Hevelius after translating the original Latin texts. We reevaluate the observations of sunspot groups by Hevelius during this period and obtain an average value 7% greater than that calculated from his observations given in the current group database. Furthermore, the average of the active day fraction obtained in this work from Hevelius's records previous to the MM is significantly greater than the solar activity level obtained from Hevelius's sunspot observations made during the MM (70% versus 30%). We also present the butterfly diagram obtained from the sunspot positions recorded by Hevelius for the period 1642-1645. It can be seen that no hemispheric asymmetry exists during this interval, in contrast with the MM. Hevelius noted a ∼3-month period that appeared to lack sunspots in early 1645 that gave the first hint of the impending MM. Recent studies claim that the MM was not a grand minimum period, speculating that astronomers of that time, due to the Aristotelian ideas, did not record all sunspots that they observed, producing thus an underestimation of the solar activity level. However, we show that the good quality of the sunspot records made by Hevelius indicates that his reports of sunspots were true to the observations.
A new software (Soonspot) for the determination of the heliographic coordinates and areas of sunspots from solar images is presented. This program is very user-friendly and the accuracy of its ...results has been checked by using solar images provided by the Debrecen Photoheliographic Data (DPD). Due to its applicability in the studies of historical solar observations, the program has been used to analyze the solar drawings carried out by Hevelius in the 17th century.
Sunspot catalogs are very useful for studying the solar activity of the recent past. In this context, a catalog covering more than three solar cycles made by the astronomers of the Madrid ...Astronomical Observatory in Spain (nowadays, the National Astronomical Observatory) from 1952 until 1986 has been recovered. Moreover, a machine-readable version of this catalog has been made available. We have recovered abundant metadata and studied the reliability of this dataset by comparing it with other sunspot catalogs.
In this paper we analyze a small collection of sunspot drawings made at the Astronomical Observatory of the Spanish Navy in the period from April 1, 1884 to August 18, 1884. We calculate the area and ...the heliographic coordinates of the observed sunspots. From these coordinates, we obtain the solar rotation rate in this period. Finally, we compare our results with the data recorded by the Royal Greenwich Observatory.
A new software (Soonspot) for the determination of the heliographic coordinates and areas of sunspots from solar images is presented. This program is very user-friendly and the accuracy of its ...results has been checked by using solar images provided by the Debrecen Photoheliographic Data (DPD). Due to its applicability in the studies of historical solar observations, the program has been used to analyze the solar drawings carried out by Hevelius in the 17th century.
An analysis of the sunspot observations made by Hevelius during 1642-1645 is presented. These records are the only systematic sunspot observations just before the Maunder Minimum. We have studied ...different phenomena meticulously recorded by Hevelius after translating the original Latin texts. We re-evaluate the observations of sunspot groups by Hevelius during this period and obtain an average value 7% greater than that calculated from his observations given in the current group database. Furthermore, the average of the active day fraction obtained in this work from Hevelius' records previous to the Maunder Minimum is significantly greater than the solar activity level obtained from Hevelius' sunspot observations made during the Maunder Minimum (70% vs. 30%). We also present the butterfly diagram obtained from the sunspot positions recorded by Hevelius for the period 1642-1645. It can be seen that no hemispheric asymmetry exists during this interval, in contrast with the Maunder Minimum. Hevelius noted a ~3-month period that appeared to lack sunspots in early 1645 that gave the first hint of the impending Maunder Minimum. Recent studies claim that the Maunder Minimum was not a grand minimum period speculating that astronomers of that time, due to the Aristotelian ideas, did not record all sunspots that they observed, producing thus an underestimation of the solar activity level. However, we show the good quality of the sunspot records made by Hevelius indicates that his reports of sunspots were true to the observations.
Sunspot catalogs are very useful for studying the solar activity of the recent past. In this context, a catalog covering more than three solar cycles made by the astronomers of the Madrid ...Astronomical Observatory in Spain (nowadays, the National Astronomical Observatory) from 1952 until 1986 has been recovered. Moreover, a machine-readable version of this catalog has been made available. We have recovered abundant metadata and studied the reliability of this dataset by comparing it with other sunspot catalogs.
This paper details research performed in the development of COTS based test program sets capable of testing various avionics systems installed in operational aircraft. The basis of this program was ...to determine the best course of action to allow the aircraft technician to troubleshoot and verify faults encountered during normal operation. This was accomplished by first developing an expert knowledge database covering problems and faults encountered by experienced aircraft technicians. The test system, dubbed the Avionics Test System (ATS), allows end-to-end performance testing of any avionics system from the installed antenna to the operator interface, visual or aural. The ATS gives the aircraft technician the ability to test the functions of the avionics systems using real-world performance criteria. The ATS end-to-end test capability tests all segments of the avionics systems giving a positive indication of faults in a real-world environment. With a graphical user interface, the technician's inputs are button presses vs. keystrokes allowing for incremental environment use. A wireless remote control capability provides the technician the ability to perform the majority of tests while seated in the cockpit or at a user station.
Several interventions have been found to be effective for reversing prediabetes in adults. This systematic review and meta-analysis aims to compare the effectiveness of such interventions.
MEDLINE, ...Embase, and Cochrane Library databases were searched for articles published between January 1, 2000 and June 27, 2018. RCTs in adults with prediabetes, testing nonsurgical interventions lasting for ≥3 months, and reporting the number of participants achieving normal glucose levels at intervention end were eligible. The pooled risk difference and number needed to treat for achieving normoglycemia were estimated using a random-effects, arm-based network meta-analysis. The strength of the evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. Data were obtained in 2018 and analyzed in 2019 and 2021.
Of 54 studies included in the systematic review, 47 were meta-analyzed (n=26,460, mean age=53 years, 46% male, 31% White). Studies included 27 arms testing lifestyle modification interventions, 25 testing medications, 5 testing dietary supplements, and 10 testing Chinese medicine. There were 35 control/placebo arms. At a median follow-up of 1.6 years, more participants in the lifestyle modification groups achieved normoglycemia than those in the control (risk difference=0.18, number needed to treat=6). The strength of the evidence was strong for lifestyle modification. Over a median follow-up of 2.7 years, more participants receiving glucagon-like peptide-1 receptor agonists (risk difference=0.47, number needed to treat=2), α-glucosidase inhibitors (risk difference=0.29, number needed to treat=4), and insulin sensitizers (risk difference=0.23, number needed to treat=4) achieved normoglycemia than control. The strength of evidence was moderate for these medications.
Although several pharmacological approaches can reverse prediabetes, lifestyle modification provides the strongest evidence of effectiveness and should remain the recommended approach to address this condition.
Objective
Levetiracetam (LEV) is an antiseizure medication prescribed to women during childbearing age. The impact of LEV on placental transporters is poorly understood. This study aimed to assess ...the effect of LEV exposure on the messenger RNA (mRNA) expression of placental transporters for hormones and nutrients and to correlate their expression with the drug's serum concentration in pregnant mice.
Methods
Studies were conducted on gestational days (GD) 13 and 18, following oral treatment with 100 mg/kg LEV or the vehicle every 24 h after weaning. Serum LEV measurements were performed by High‐performance liquid chromatography with a UV detector (HPLC‐UV). The weight, height, and width of the fetuses were also analyzed. In addition, the placental expression of transporters xCt, Lat1, Oatp4a1, Fr‐α, Rfc, and Snat4 was evaluated through semi‐quantitative real‐time polymerase chain reaction (qPCR). The Kruskal‐Wallis and the Mann‐Whitney U tests were used to determine the statistical significance (p < .05). The correlation between serum LEV concentration and placental gene expression was evaluated using the Spearman test.
Results
The weight, height, and width were lower in the fetuses exposed to LEV compared with the control group (p < .05). The number of fetuses was lower in the LEV‐exposed group than in the control GD 13 group (p < .001). No significant differences were detected in the mRNA expression level at GD 13. At GD 18, the expression of Lat1, Oatp4a1, xCT, and Snat4 was higher in the group treated with LEV compared with the control group (p < .05), whereas the expression of Rfc was lower (p < .05). No correlation was identified between serum LEV concentrations and gene expression levels.
Significance
The repression of the Rfc transcript by LEV at GD 18 suggests that the protein expression would be abolished contributing to the observed intrauterine growth restriction (IUGR). Furthermore, the significant increase in mRNA of xCt, Snat4, Oatp4a1, and Lat1 might be a compensatory mechanism for fetal survival at GD 18.
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