| 1. |
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| 2. |
- Quanz, S. P., et al.
(författare)
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Large Interferometer For Exoplanets (LIFE) I. Improved exoplanet detection yield estimates for a large mid-infrared space-interferometer mission
- 2022
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 664
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Tidskriftsartikel (refereegranskat)abstract
- Context. One of the long-term goals of exoplanet science is the atmospheric characterization of dozens of small exoplanets in order to understand their diversity and search for habitable worlds and potential biosignatures. Achieving this goal requires a space mission of sufficient scale that can spatially separate the signals from exoplanets and their host stars and thus directly scrutinize the exoplanets and their atmospheres.Aims. We seek to quantify the exoplanet detection performance of a space-based mid-infrared (MIR) nulling interferometer that measures the thermal emission of exoplanets. We study the impact of various parameters and compare the performance with that of large single-aperture mission concepts that detect exoplanets in reflected light.Methods. We have developed an instrument simulator that considers all major astrophysical noise sources and coupled it with Monte Carlo simulations of a synthetic exoplanet population around main-sequence stars within 20 pc of the Sun. This allows us to quantify the number (and types) of exoplanets that our mission concept could detect. Considering single visits only, we discuss two different scenarios for distributing 2.5 yr of an initial search phase among the stellar targets. Different apertures sizes and wavelength ranges are investigated.Results. An interferometer consisting of four 2 m apertures working in the 4–18.5 μ.m wavelength range with a total instrument throughput of 5% could detect up to ≈550 exoplanets with radii between 0.5 and 6 R⊕ with an integrated S/N ≥ 7. At least ≈160 of the detected exoplanets have radii ≤1.5 R⊕. Depending on the observing scenario, ≈25–45 rocky exoplanets (objects with radii between 0.5 and 1.5 R⊕) orbiting within the empirical habitable zone (eHZ) of their host stars are among the detections. With four 3.5 m apertures, the total number of detections can increase to up to ≈770, including ≈60–80 rocky eHZ planets. With four times 1 m apertures, the maximum detection yield is ≈315 exoplanets, including ≤20 rocky eHZ planets. The vast majority of small, temperate exoplanets are detected around M dwarfs. The impact of changing the wavelength range to 3–20 μm or 6–17 μm on the detection yield is negligible.Conclusions. A large space-based MIR nulling interferometer will be able to directly detect hundreds of small, nearby exoplanets, tens of which would be habitable world candidates. This shows that such a mission can compete with large single-aperture reflected light missions. Further increasing the number of habitable world candidates, in particular around solar-type stars, appears possible via the implementation of a multi-visit strategy during the search phase. The high median S/N of most of the detected planets will allow for first estimates of their radii and effective temperatures and will help prioritize the targets for a second mission phase to obtain high-S/N thermal emission spectra, leveraging the superior diagnostic power of the MIR regime compared to shorter wavelengths.
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| 3. |
- Aubert, S, et al.
(författare)
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Global Matrix 4.0 Physical Activity Report Card Grades for Children and Adolescents: Results and Analyses From 57 Countries
- 2022
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Ingår i: Journal of physical activity & health. - : Human Kinetics. - 1543-5474 .- 1543-3080. ; 19:11, s. 700-728
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Tidskriftsartikel (refereegranskat)abstract
- Background: The Global Matrix 4.0 on physical activity (PA) for children and adolescents was developed to achieve a comprehensive understanding of the global variation in children’s and adolescents’ (5–17 y) PA, related measures, and key sources of influence. The objectives of this article were (1) to summarize the findings from the Global Matrix 4.0 Report Cards, (2) to compare indicators across countries, and (3) to explore trends related to the Human Development Index and geo-cultural regions. Methods: A total of 57 Report Card teams followed a harmonized process to grade the 10 common PA indicators. An online survey was conducted to collect Report Card Leaders’ top 3 priorities for each PA indicator and their opinions on how the COVID-19 pandemic impacted child and adolescent PA indicators in their country. Results: Overall Physical Activity was the indicator with the lowest global average grade (D), while School and Community and Environment were the indicators with the highest global average grade (C+). An overview of the global situation in terms of surveillance and prevalence is provided for all 10 common PA indicators, followed by priorities and examples to support the development of strategies and policies internationally. Conclusions: The Global Matrix 4.0 represents the largest compilation of children’s and adolescents’ PA indicators to date. While variation in data sources informing the grades across countries was observed, this initiative highlighted low PA levels in children and adolescents globally. Measures to contain the COVID-19 pandemic, local/international conflicts, climate change, and economic change threaten to worsen this situation.
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| 4. |
- Hemingway, F., et al.
(författare)
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Smooth muscle actin expression in primary bone tumours
- 2012
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Ingår i: Virchows Archiv: an international journal of pathology. - : Springer Science and Business Media LLC. - 1432-2307. ; 460:5, s. 525-534
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Tidskriftsartikel (refereegranskat)abstract
- Alpha isoform of smooth muscle actin (SMA) expression has been reported in giant cell tumour of bone (GCTB) and other benign and malignant bone tumours, but the pattern of SMA expression and the precise nature of SMA-expressing cells in these lesions is uncertain. We determined by immunohistochemistry the expression of SMA and other muscle and vascular markers in normal bone, GCTB and a wide range of primary benign and malignant bone tumours. Cultured stromal cells of GCTB, chondroblastoma (CB), and aneurysmal bone cyst (ABC) were also analysed for SMA expression. SMA was only noted in blood vessels in normal bone. SMA was expressed by mononuclear stromal cells (MSC) cultured from GCTB, ABC and CB. SMA was strongly and diffusely expressed by MSC in non-ossifying fibroma, fibrous dysplasia, and "brown tumour" of hyperparathyroidism. SMA expression was also noted in GCTB, ABC, CB, chondromyxoid fibroma, malignant fibrous histiocytoma of bone and osteosarcoma. Little or no SMA was noted in Langerhans cell histiocytosis, simple bone cyst, Ewing's sarcoma, osteoblastoma, osteoid osteoma, enchondroma, osteochondroma, chondrosarcoma, myeloma, lymphoma, chordoma and adamantinoma. Our findings show that there is differential SMA expression in primary bone tumours and that identifying the presence or absence of SMA is useful in the differential diagnosis of these lesions. The nature of SMA-expressing cells in bone tumours is uncertain but they are negative for desmin and caldesmon and could represent either myofibroblasts or perivascular cells, such as pericytes.
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| 5. |
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| 6. |
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| 7. |
- Yu, Bao-Zhu, et al.
(författare)
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Effect of Guggulsterone and Cembranoids of Commiphora mukul on Pancreatic Phospholipase A(2) : Role in Hypocholesterolemia
- 2009
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Ingår i: Journal of natural products (Print). - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 72:1, s. 24-28
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Tidskriftsartikel (refereegranskat)abstract
- Guggulsterone (7) and cembranoids (8-12) from Commiphora mukul stem bark resin guggul were shown to be specific modulators of two independent sites that are also modulated by bile salts (1-6) to control cholesterol absorption and catabolism. Guggulsterone (7) antagonized the chenodeoxycholic acid (3)-activated nuclear farnesoid X receptor (FXR), which regulates cholesterol metabolism in the liver. The cembranoids did not show a noticeable effect on FXR, but lowered the cholate (I)-activated rate of human pancreatic 113 phospholipase A2 (hPLA2), which controls gastrointestinal absorption of fat and cholesterol. Analysis of the data using a kinetic model has suggested an allosteric mechanism for the rate increase of hPLA2 by cholate and also for the rate-lowering effect by certain bile salts or cembranoids on the cholate-activated hPLA2 hydrolysis of phosphatidylcholine vesicles. The allosteric inhibition of PLA2 by certain bile salts and cembranoids showed some structural specificity. Biophysical studies also showed specific interaction of the bile salts with the interface-bound cholate-activated PLA2. Since cholesterol homeostasis in mammals is regulated by FXR in the liver for metabolism and by PLA2 in the intestine for absorption, modulation of PLA2 and FXR by bile acids and selected guggul components suggests novel possibilities for hypolipidemic and hypocholesterolemic therapies.
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| 8. |
- Abdalla, Abdalla M., et al.
(författare)
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Synthesis and characterization of Sm1-xZrxFe1-yMgyO3 (x, y = 0.5, 0.7, 0.9) as possible electrolytes for SOFCs
- 2018
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Ingår i: Key Engineering Materials. - 1013-9826 .- 1662-9795. ; 765 KEM, s. 49-53
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Konferensbidrag (refereegranskat)abstract
- The novel perovskite oxide series of Sm 1-x Zr x Fe 1-y Mg y O 3 (x,y = 0.5, 0.7, 0.9) were synthesized by solid state reaction method. X-ray diffraction (XRD), Rietveld refinement, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and conductivity analysis were carried out. XRD patterns of sintered materials revealed the shifted Bragg reflection to higher angle for the higher content of Zr and Mg. This is related to the ionic size of the dopant elements. Rietveld refinement showed that all compounds crystallized in cubic space group of Fm-3m. SEM images showed that the grains were well defined with highly dense surfaces makes it potential as an electrolyte material in solid oxide fuel cells (SOFCs) or gases sensors. Impedance spectroscopy at 550-800 °C shows that conductivity is higher at higher temperature. Sm 0.5 Zr 0.5 Fe 0.5 Mg 0.5 O 3 shows the highest conductivity of 5.451 × 10 -3 S cm -1 at 800 °C. It was observed that 50% molar ratio of Mg and Zr doping performed highest conductivity.
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| 9. |
- Abegunawardana, Sidath, et al.
(författare)
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Audible Frequency Analysis of Ground Flashes
- 2018
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Konferensbidrag (refereegranskat)abstract
- Thunder signatures categorized into three types based on peak pressure and variation in fundamental frequency, have been studied by using acoustic spectrum of thunder. S-transformation has been used to estimate the dominant frequency variation around the peak pressure. The mean fundamental frequencies of type 3 ground and cloud flashes are 160 Hz and 98 Hz respectively. The mean frequencies of type 2 ground and cloud flashes are 108 Hz and 82 Hz respectively.
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| 10. |
- Abegunawardana, Sidath, et al.
(författare)
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Sound Source Localization of Lightning Discharges
- 2018
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Konferensbidrag (refereegranskat)abstract
- The lightning channel can be retraced by thunder signature recorded with an array of microphones. Four microphones were arranged to capture thunder sound, and acoustic cross-correlation of captured pressure signals estimated the time lag of each pair of microphones. A wave segment with 0.25 s or 0.5 s of duration was compared with the acoustic signal recorded by other microphones to estimate time lapse. The direction of channel propagation has been estimated by the time difference of arrival of each pair of microphones. Thunder source locations estimated by this method can be extended to investigate the channel propagation inside clouds.
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| 11. |
- Ahmad, Noor Azlinda, et al.
(författare)
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Characteristics of narrow bipolar pulses observed in Malaysia
- 2010
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Ingår i: Journal of Atmospheric and Solar-Terrestrial Physics. - : Elsevier BV. - 1364-6826 .- 1879-1824. ; 72:5-6, s. 534-540
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Tidskriftsartikel (refereegranskat)abstract
- Narrow bipolar pulses (NBPs) are considered as isolated intracloud events with higher peak amplitude and strong high frequency emission compared to the first return strokes and other intracloud discharges. From 182 NBPs recorded in Malaysia in the tropic, 75 were narrow negative bipolar pulses (NNBPs) while 107 were narrow positive bipolar pulses (NPBPs). The mean duration of NNBPs was 24.6 +/- 17.1 mu s, while 30.2 +/- 12.3 mu s was observed for NPBPs. The mean full-width at half-maximum (FVVHM) was 2.2 +/- 0.7 and 2.4 +/- 1.4 mu s for NNBPs and NPBPs, respectively. The mean peak amplitude of NPBPs normalized to 100 km was 22.7 V/m, a factor of 1.3 higher than that of NNBPs which is 17.6 V/m. In contrast to the previous studies, it was observed that the electric field change was characterized by a bipolar pulse with a significant amount of fine structures separated by a few tens of nanoseconds intervals, embedded on it. (C) 2010 Elsevier Ltd. All rights reserved.
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| 12. |
- Ahmad, Noor Azlinda, et al.
(författare)
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The first electric field pulse of cloud and cloud-to-ground lightning discharges
- 2010
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Ingår i: Journal of Atmospheric and Solar-Terrestrial Physics. - : Elsevier BV. - 1364-6826 .- 1879-1824. ; 72:2-3, s. 143-150
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the first electric field pulse of cloud and cloud-to-ground discharges were analyzed and compared with other pulses of cloud discharges. Thirty eight cloud discharges and 101 cloud-to-ground discharges have been studied in this analysis. Pulses in cloud discharges were classified as [`]small', [`]medium' and [`]large', depending upon the value of their relative amplitude with respect to that of the average amplitude of the five largest pulses in the flash. We found that parameters, such as pulse duration, rise time, zero crossing time and full-width at half-maximum (FWHMs) of the first pulse of cloud and cloud-to-ground discharges are similar to small pulses that appear in the later stage of cloud discharges. Hence, we suggest that the mechanism of the first pulse of cloud and cloud-to-ground discharges and the mechanism of pulses at the later stage of cloud discharges could be the same.
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| 13. |
- Baharudin, Zikri A., et al.
(författare)
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Negative cloud-to-ground lightning flashes in Malaysia
- 2014
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Ingår i: Journal of Atmospheric and Solar-Terrestrial Physics. - : Elsevier BV. - 1364-6826 .- 1879-1824. ; 108, s. 61-67
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Tidskriftsartikel (refereegranskat)abstract
- The characteristics of the negative cloud-to-ground lightning flashes in Malaysia are studied by analyzing the electric fields generated by the whole flash in nanosecond resolution. A total of 405 strokes obtained from 100 successive negative cloud-to-ground lightning flashes were analyzed, which were recorded from seven convective thunderstorms during the southwest monsoon period, i.e. from April to June 2009. It was found that the total number of interstroke intervals has an arithmetic mean value of 86 ms, a geometric mean value of 67 ms and does not depend on the return stroke order. Of the 100 negative ground flashes, 38 flashes (38%) have at least one subsequent return-stroke (SRS) whose electric field peak was greater than that of the first return-stroke (RS). Furthermore, 58 (19%) out of 305 SRS have electric field peak larger than those of the first RS. The arithmetic and geometric mean ratio between the peak electric field of the SRS and the peak electric field of the first RS are 0.7 and 0.6, respectively. The percentage of single-stroke flashes was 16% while the mean number of strokes per flash and maximum number of stroke per flash were 4 and 14, respectively.
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| 14. |
- Berg, Otto, et al.
(författare)
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Cooperative binding of monodisperse anionic amphiphiles to the i-Face : Phospholipase A2-paradigm for interfacial binding
- 2004
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Ingår i: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 43:25, s. 7999-8013
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Tidskriftsartikel (refereegranskat)abstract
- Equilibrium parameters for the binding of monodisperse alkyl sulfate along the i-face (the interface binding surface) of pig pancreatic IB phospholipase A2 (PLA2) to form the premicellar complexes (Ei#) are characterized to discern the short-range specific interactions. Typically, Ei# complexes are reversible on dilution. The triphasic binding isotherm, monitored as the fluorescence emission from the single tryptophan of PLA2, is interpreted as a cooperative equilibrium for the sequential formation of three premicellar complexes (Ei#, i = 1, 2, 3). In the presence of calcium, the dissociation constant K1 for the E1# complex of PLA2 with decyl sulfate (CMC = 4500 μM) is 70 μM with a Hill coefficient n1 = 2.1 ± 0.2; K2 for E2# is 750 μM with n2 = 8 ± 1, and K3 for E3# is 4000 μM with an n3 value of about 12. Controls show that (a) self-aggregation of decyl sulfate alone is not significant below the CMC; (b) occupancy of the active site is not necessary for the formation of Ei#; (c) Ki and ni do not change significantly due to the absence of calcium, possibly because alkyl sulfate does not bind to the active site of PLA2; (d) the Ei# complexes show a significant propensity for aggregation; and (e) PLA2 is not denatured in Ei#. The results are interpreted to elaborate the model for atomic level interactions along the i-face: The chain length dependence of the fit parameters suggests that short-range specific anion binding of the headgroup is accompanied by desolvation of the i-face of Ei#. We suggest that allosteric activation of PLA2 results from such specific interactions of the amphiplies and the desolvation of the i-face. The significance of these primary interfacial binding events and the coexistence of the E* and Ei# aggregates is discussed.
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| 15. |
- Bodhika, J. A. P., et al.
(författare)
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A preliminary study on characteristics of thunder pulses of lightning
- 2014
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Ingår i: 2014 INTERNATIONAL CONFERENCE ON LIGHTNING PROTECTION (ICLP). - : IEEE conference proceedings. - 9781479935444 ; , s. 260-264
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Konferensbidrag (refereegranskat)abstract
- Thunder is the acoustic emission associated with lightning discharges. Thunder signatures have been analyzed by many scientists with the aim of understanding the energy, channel tortuosity and localization of lightning channel. In describing thunder features, a few subjective terms such as clap, roll and rumble have been used in the literature inconsistently with no proper definitions. In this study the features of pressure pulses such as occurrence characteristics and their relative amplitudes were analyzed to understand some of the above mentioned thunder features. Those subjective terms, clap, peal, roll and rumble were quantified along with relative pulse amplitudes and confirmed by listening the recorded thunder signals carefully. The relative peak amplitudes of the pulses of rumble were less than 20% of the peak pulses of the thunder signal and for roll it was between 20% to 40%. Pulses with relative amplitudes greater than 40% were identified as claps. The most significant contribution to the sound in a thunder flash is due to claps, which was studied separately in this study. The number of claps in a thunder flash, their frequency variation, durations, and pulse characteristics has been studied. The frequency of pressure oscillations within these claps are being less than 300 Hz. According to this study, 62% of the flashes consist of 1 to 2 claps. The activity of the thunder signal is high in initial half than the latter half. Thunder signals analyzed in this study is recorded by a microphone system with wide bandwidth range from 6 to 20 kHz.
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| 16. |
- Bodhika, J. A. P., et al.
(författare)
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Characteristics of thunder pertinent to tropical lightning
- 2018
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Ingår i: 34th International Conference on Lightning Protection (ICLP) (ICLP 2018). - : IEEE. - 9781538666357
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Konferensbidrag (refereegranskat)abstract
- Acoustic effects of lightning flashes are not well studied. Thunder also destructive as electric fields do. Thunder flashes of tropical lightning occurred in Hambantota (81(0) 0'E, 6(0) 10'N) close to the southern coast of Sri Lanka were studied. About 90 thunder flashes recorded with the sampling rate of 100 kS/s in 45 s windows were analyzed to identify their characteristics and damaging effects. Results of the analysis on duration of thunder flashes, peak sound pressure levels, occurrence of thunder claps and frequency distribution were presented. The shortest and longest duration of thunder recorded were 2.2 sec and 33.7 sec respectively. About 75% of thunder flashes were remained for about 5-20 sec. The frequency spectrum of a thunder signal could spread up to 1500 Hz. The peak sound pressure level of 30% of recorded thunder flashes at least 3 km away from the lightning were higher than 2 Nm(-2) (100 dB). One to five claps were identified in thunder flashes with 62% having 1 or 2 claps. Sound pressure level, frequency range and its duration are required quantities to estimate the harmful effects of thunder.
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| 17. |
- Bodhika, J. A. P., et al.
(författare)
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Reconstruction of lightning channel geometry by localizing thunder sources
- 2013
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Ingår i: Journal of Atmospheric and Solar-Terrestrial Physics. - : Elsevier BV. - 1364-6826 .- 1879-1824. ; 102, s. 81-90
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Tidskriftsartikel (refereegranskat)abstract
- Thunder is generated as a result of a shock wave created by sudden expansion of air in the lightning channel due to high temperature variations. Even though the highest amplitudes of thunder signatures are generated at the return stroke stage, thunder signals generated at other events such as preliminary breakdown pulses also can be of amplitudes which are large enough to record using a sensitive system. In this study, it was attempted to reconstruct the lightning channel geometry of cloud and ground flashes by locating the temporal and spatial variations of thunder sources. Six lightning flashes were reconstructed using the recorded thunder signatures. Possible effects due to atmospheric conditions were neglected. Numerical calculations suggest that the time resolution of the recorded signal and 10 ms(-1)error in speed of sound leads to 2% and 3% errors, respectively, in the calculated coordinates. Reconstructed channel geometries for cloud and ground flashes agreed with the visual observations. Results suggest that the lightning channel can be successfully reconstructed using this technique.
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| 18. |
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| 19. |
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| 20. |
- Gunasekara, T.A.L.N., et al.
(författare)
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Time-Frequency Analysis of vertical and horizontal electric field changes of lightning negative return strokes observed in Sri Lanka
- 2018
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Ingår i: Journal of Atmospheric and Solar-Terrestrial Physics. - : Elsevier BV. - 1364-6826 .- 1879-1824. ; 179, s. 34-39
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Tidskriftsartikel (refereegranskat)abstract
- Simultaneously captured vertical and horizontal (total) electric field signatures of lightning negative Return Strokes (RS) were analyzed to obtain Time-Frequency (TF) variation using Stockwell Transformation (ST). In the study, ST was utilized since it is known to possess comparatively better time resolution at high frequency regions compared to other available TF methods. The data were obtained during the monsoon season of April–May 2014. The vertical and horizontal component of fifty negative RSs was utilized in the study. The resultant ST spectrum was analyzed and the regions of interest were demarcated based on the color which represented their relative power output intensities for different frequency components of the signal. The spread area was identified as the region of frequencies which consisted of power intensity equal or above 90th percentile when compared to the maximum possible value. The spectral area was identified as the area of frequencies in the borderline to the natural background noise. The spread region for the vertical E field had a range between 10 kHz and 650 kHz. Its average values were in between 126 kHz and 331 kHz. The spectral region of the vertical electric field change spanned from 1 kHz to 1020 kHz. Its average distribution was 44 kHz–660 kHz. Horizontal electric fields had a range of 20 kHz–1940 kHz in the spectral region. The same for the spread region was 80 kHz–910 kHz. The averages of the horizontal E field's spectral region were 46–1112 kHz and its spread region varied between 227 and 599 kHz. The results display a higher frequency range for all aspects of the horizontal E field changes which implies that its influence on the high frequency radiation is much higher than its vertical counterpart.
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| 21. |
- Perera, Chandana, et al.
(författare)
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Continuing Currents and Luminosity of Cloud Flashes
- 2014
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Ingår i: 2014 INTERNATIONAL CONFERENCE ON LIGHTNING PROTECTION (ICLP). - : IEEE conference proceedings. - 9781479935444 ; , s. 1587-1593
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Konferensbidrag (refereegranskat)abstract
- In this study, continuing currents and luminosity of cloud flashes were investigated using time resolve photographic technique. In ground flashes, the flow of current after the end of the return stroke is called the continuing currents. Typical cloud flashes have two stages called early stage (or active stage) and final or late stage. The continuing current and luminosities reported in this paper are observed in late stage of the cloud flashes. In ground flashes the shortest reported duration of continuing current is longer than the 3 ms. For the first time in literature the continuing currents in cloud flashes were studied. No major difference between the time duration of continuing currents of ground flashes and long current variation of cloud flashes were observed.
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| 22. |
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| 23. |
- Shukla, Mahendra, et al.
(författare)
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Model based population PK-PD analysis of furosemide for BP lowering effect : A comparative study in primary and secondary hypertension
- 2017
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Ingår i: European Journal of Pharmaceutical Sciences. - : Elsevier BV. - 0928-0987 .- 1879-0720. ; 109, s. 253-261
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Tidskriftsartikel (refereegranskat)abstract
- Though numerous reports have demonstrated multiple mechanisms by which furosemide can exert its antihypertensive response. However, lack of studies describing PK-PD relationship for furosemide featuring its antihypertensive property has limited its usage as a blood pressure (BP) lowering agent. Serum concentrations and mean arterial BP were monitored following 40 and 80 mg kg(-1) multiple oral dose of furosemide in spontaneously hypertensive rats (SHR) and DOCA-salt induced hypertensive (DOCA-salt) rats. A simultaneous population PK-PD relationship using Emax model with effect compartment was developed to compare the anti-hypertensive efficacy of furosemide in these rat models. A two-compartment PK model with Weibull-type absorption and first-order elimination best described the serum concentration-time profile of furosemide. In the present study, post dose serum concentrations of furosemide were found to be lower than the EC50. The EC50 predicted in DOCA-salt rats was found to be lower (4.5-fold), whereas the tolerance development was higher than that in SHR model. The PK-PD parameter estimates, particularly lower values of EC50, Ke and Q in DOCA-salt rats as compared to SHR, pinpointed the higher BP lowering efficacy of furosemide in volume overload induced hypertensive conditions. Insignificantly altered serum creatinine and electrolyte levels indicated a favorable side effect profile of furosemide. In conclusion, the final PK-PD model described the data well and provides detailed insights into the use of furosemide as an anti-hypertensive agent.
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| 24. |
- Vayanganie, S.P.A, et al.
(författare)
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High Speed Optical Observations of Cloud Flashes
- 2014
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Ingår i: 2014 INTERNATIONAL CONFERENCE ON LIGHTNING PROTECTION (ICLP). - : IEEE conference proceedings. - 9781479935444 ; , s. 752-755
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Konferensbidrag (refereegranskat)abstract
- Luminosity variations of natural cloud lightning channels were studied using high speed video recordings in Sri Lanka in the tropic. Five cloud flashes were selected for the study, which were recorded with 5000 fps with 512X512 pixel resolution. Luminosity variation along channels and along selected channel segment, duration of cloud activities was studied. It was found that the average duration of selected flashes is 266.44 ms. No particular pattern was observed for the luminosity variation along channel segments. However the luminosity variation across the channel followed a Gaussian distribution pattern. Pattern of the luminosity variation along channels were compared with existing models to understand the development process of cloud flashes. Results show that it is hard to collaborate the observation to a single process for cloud discharges.
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