scholarly journals A 35-GHz Polarimetric Doppler Radar for Long-Term Observations of Cloud Parameters—Description of System and Data Processing

2015 ◽  
Vol 32 (4) ◽  
pp. 675-690 ◽  
Author(s):  
Ulrich Görsdorf ◽  
Volker Lehmann ◽  
Matthias Bauer-Pfundstein ◽  
Gerhard Peters ◽  
Dmytro Vavriv ◽  
...  

AbstractA 35-GHz radar has been operating at the Meteorological Observatory Lindenberg (Germany) since 2004, measuring cloud parameters continuously. The radar is equipped with a powerful magnetron transmitter and a high-gain antenna resulting in a high sensitivity of −55 dBZ at 5-km height for a 10-s averaging time. The main purpose of the radar is to provide long-term datasets of cloud parameters for model evaluation, satellite validation, and climatological studies. Therefore, the system operates with largely unchanged parameter settings and a vertically pointing antenna. The accuracy of the internal calibration (budget calibration) has been appraised to be 1.3 dB. Cloud parameters are derived by two different approaches: macrophysical parameters have been deduced for the complete period of operation through combination with ceilometer measurements; a more enhanced target classification and the calculation of liquid and ice water contents are realized by algorithms developed in the framework of the European CloudNet project.

2016 ◽  
Vol 4 (48) ◽  
pp. 7845-7851 ◽  
Author(s):  
Junpeng Shi ◽  
Meng Sun ◽  
Xia Sun ◽  
Hongwu Zhang

Near-infrared persistent luminescence hollow mesoporous nanospheres have been synthesized via a template method. These nanospheres can be used as large capacity drug carriers and realize super long-term and high sensitivity tracking of drug delivery in deep tissue.


2016 ◽  
Vol 23 (2) ◽  
pp. 124-131 ◽  
Author(s):  
Mateja Kaja Jezovnik ◽  
Jawed Fareed ◽  
Pavel Poredos

Introduction: Although the role of inflammation in DVT has been investigated in different studies, there is no definite answer as to whether increased systemic inflammation is the cause or the consequence of DVT. Aim: To follow inflammatory parameters in a cohort of patients with idiopathic DVT. Methods: Out of 49 patients with an acute idiopathic DVT, which were investigated four months after an acute episode (DEVTA 1), 43 patients were included in the follow-up study investigating inflammatory markers and hemostatic markers of endothelial damage five years after an acute DVT (DEVTA 2). A control group consisted of 43 sex and age matched healthy subjects (CONTROLS). Results: The levels of inflammatory markers were significantly higher in DEVTA 2 in comparison to CONTROLS: tumor necrosis factor alpha 2.0 pg/mL (1.1-2.3) vs 1.3 pg/mL (0.8-1.9), p < .001, high sensitivity C-reactive protein 3.2 mg/L (1.5-5.2) vs 1.7 mg/L (0.9-3.0), p = .008, interleukin-6 (IL-6) 2.7 pg/mL (2.0-3.5) vs 2.1 pg/mL (1.5-2.6), p = .025, IL-8 5.0 pg/mL (3.6-7.3) vs 2.4 pg/mL (1.8-2.8), p < .001. IL-10 was significantly decreased (0.9 pg/mL (0.7-1.8) vs 1.8 (1.5-2.2), p < .001. Most of the proinflammatory markers remained elevated in the DEVTA 2 in comparison to DEVTA 1. Markers of endothelial damage were higher in DEVTA 2 in comparison to CONTROLS and higher than in DEVTA 1. Conclusion: Patients with idiopathic DVT have long-term increased inflammatory markers and markers of endothelial damage. These findings favor the hypothesis that inflammation is a cause and not merely a consequence of acute DVT.


2016 ◽  
Vol 62 (2) ◽  
pp. 360-366 ◽  
Author(s):  
Emily I Schindler ◽  
Jeffrey J Szymanski ◽  
Karl G Hock ◽  
Edward M Geltman ◽  
Mitchell G Scott

Abstract BACKGROUND Galectin-3 (Gal-3) has been suggested as a prognostic biomarker in heart failure (HF) patients that may better reflect disease progression than traditional markers, including B-type natriuretic peptide (BNP) and cardiac troponins. To fully establish the utility of any biomarker in HF, its biologic variability must be characterized. METHODS To assess biologic variability, 59 patients were prospectively recruited, including 23 male and 16 female patients with stable HF and 10 male and 10 female healthy individuals. Gal-3, BNP, and high-sensitivity cardiac troponin I (hs-cTnI) were assayed at 5 time points within a 3-week period to assess short-term biologic variability. Long-term (3-month) biologic variability was assessed with samples collected at enrollment and after 4, 8, and 12 weeks. RESULTS Among healthy individuals, mean short-term biologic variability, expressed as intraindividual CV (CVI), was 4.5% for Gal-3, 29.0% for BNP, and 14.5% for hs-cTnI; long-term biologic variability was 5.5% for Gal-3, 34.7% for BNP, and 14.7% for hs-cTnI. In stable HF patients, mean short-term biologic variability was 7.1% for Gal-3, 22.5% for BNP, and 8.5% for hs-cTnI, and mean long-term biologic variability was 7.7% for Gal-3, 27.6% for BNP, and 9.6% for hs-cTnI. CONCLUSIONS The finding that Gal-3 has minimal intraindividual biological variability adds to its potential as a useful biomarker in HF patients.


2020 ◽  
Vol 4 (1) ◽  
pp. 5
Author(s):  
Elena Volpert ◽  
Natalia Chubarova

The temporal variability of solar shortwave radiation (SSR) has been assessed over northern Eurasia (40°–80° N; 10° W–180° E) by using an SSR reconstruction model since the middle of the 20th century. The reconstruction model estimates the year-to-year SSR variability as a sum of variations in SSR due to changes in aerosol, effective cloud amount and cloud optical thickness, which are the most effective factors affecting SSR. The retrievals of year-to-year SSR variations according to different factors were tested against long-term measurements in the Moscow State University Meteorological Observatory from 1968–2016. The reconstructed changes show a good agreement with measurements with determination factor R2 = 0.8. The analysis of SSR trends since 1979 has detected a significant growth of 2.5% per decade, which may be explained by its increase due to the change in cloud amount (+2.4% per decade) and aerosol optical thickness (+0.4% per decade). The trend due to cloud optical thickness was statistically insignificant. Using the SSR reconstruction model, we obtained the long-term SSR variability due to different factors for the territory of northern Eurasia. The increasing SSR trends have been detected on most sites since 1979. The long-term SSR variability over northern Eurasia is effectively explained by changes in cloud amount and, in addition, by changes in aerosol loading over the polluted regions. The retrievals of the SSR variations showed a good agreement with the changes in global radiance measurements from the World Radiation Data Center (WRDC) archive. The work was supported by RFBR grant number 18-05-00700.


2018 ◽  
Vol 31 (21) ◽  
pp. 8705-8718 ◽  
Author(s):  
Bida Jian ◽  
Jiming Li ◽  
Guoyin Wang ◽  
Yongli He ◽  
Ying Han ◽  
...  

Planetary albedo (PA; shortwave broadband albedo) and its long-term variations, which are controlled in a complex way by various atmospheric and surface properties, play a key role in controlling the global and regional energy budget. This study investigates the contributions of different atmospheric and surface properties to the long-term variations of PA based on 13 years (2003–15) of albedo, cloud, and ice coverage datasets from the Clouds and the Earth’s Radiant Energy System (CERES) Single Scanner Footprint edition 4A product, vegetation product from Moderate Resolution Imaging Spectroradiometer (MODIS), and surface albedo product from the Cloud, Albedo, and Radiation dataset, version 2 (CLARA-A2). According to the temporal correlation analysis, statistical results indicate that variations in PA are closely related to the variations of cloud properties (e.g., cloud fraction, ice water path, and liquid water path) and surface parameters (e.g., ice/snow percent coverage and normalized difference vegetation index), but their temporal relationships vary among the different regions. Generally, the stepwise multiple linear regression models can capture the observed PA anomalies for most regions. Based on the contribution calculation, cloud fraction dominates the variability of PA in the mid- and low latitudes while ice/snow percent coverage (or surface albedo) dominates the variability in the mid- and high latitudes. Changes in cloud liquid water path and ice water path are the secondary dominant factor over most regions, whereas change in vegetation cover is the least important factor over land. These results verify the effects of atmospheric and surface factors on planetary albedo changes and thus may be of benefit for improving the parameterization of the PA and determining the climate feedbacks.


2007 ◽  
Vol 64 (4) ◽  
pp. 1068-1088 ◽  
Author(s):  
Andrew J. Heymsfield ◽  
Gerd-Jan van Zadelhoff ◽  
David P. Donovan ◽  
Frederic Fabry ◽  
Robin J. Hogan ◽  
...  

Abstract This two-part study addresses the development of reliable estimates of the mass and fall speed of single ice particles and ensembles. Part I of the study reports temperature-dependent coefficients for the mass-dimensional relationship, m = aDb, where D is particle maximum dimension. The fall velocity relationship, Vt = ADB, is developed from observations in synoptic and low-latitude, convectively generated, ice cloud layers, sampled over a wide range of temperatures using an assumed range for the exponent b. Values for a, A, and B were found that were consistent with the measured particle size distributions (PSD) and the ice water content (IWC). To refine the estimates of coefficients a and b to fit both lower and higher moments of the PSD and the associated values for A and B, Part II uses the PSD from Part I plus coincident, vertically pointing Doppler radar returns. The observations and derived coefficients are used to evaluate earlier, single-moment, bulk ice microphysical parameterization schemes as well as to develop improved, statistically based, microphysical relationships. They may be used in cloud and climate models, and to retrieve cloud properties from ground-based Doppler radar and spaceborne, conventional radar returns.


Nanoscale ◽  
2014 ◽  
Vol 6 (12) ◽  
pp. 6521-6525 ◽  
Author(s):  
Ming Zhuo ◽  
Yuejiao Chen ◽  
Tao Fu ◽  
Haonan Zhang ◽  
Zhi Xu ◽  
...  

Ni(SO4)0.3(OH)1.4 nanobelts are utilized in a humidity sensor by a facile method. The nanobelt based sensor shows a high sensitivity, fast response and long-term stability in the sensing process.


2018 ◽  
Vol 17 (2) ◽  
pp. 783-810
Author(s):  
Angélica Pott de Medeiros ◽  
Giulia Xisto de Oliveira ◽  
Reisoli Bender Filho

Resumo: O cenário de instabilidade política, a recessão econômica e as mudanças nas regras de concessão de crédito pautaram o objetivo de examinar o relacionamento do crédito consignado, por segmento de concessão, com variáveis macroeconômicas, caso do consumo, da produção industrial e do produto agregado, na última década (2007-2017). Os resultados foram obtidos por meio da estimação do vetor de correção de erros, funções de impulso-resposta e decomposição da variância, possibilitando a análise das relações de curto e de longo prazo entre as séries temporais e indicaram que as diferentes modalidades do crédito consignado implicam efeitos distintos sobre as variáveis econômicas em curto prazo. O segmento de aposentados e pensionistas impacta positivamente ambas as variáveis analisadas, com destaque para os bens de consumo das famílias. Já a concessão ao setor privado, embora represente a menor parcela do crédito consignado concedido, mostrou elevada sensibilidade a alterações na oferta dessa modalidade de crédito, enquanto que o crédito ao setor público, de maior participação, apresentou efeitos reduzidos e de curta duração.Palavras-chave: Crédito consignado. Segmentos. Economia brasileira. Payroll loans: segments and economic effects Abstract: The environment of political instability, economic recession and changes in the rules of granting credit were guiders to aim to examine the payroll loans relationship, by concession segment, with macroeconomic variables, case of consumption, industrial production and aggregate product, in the last decade (2007-2017). The results obtained by error correction vector estimation, and functions of impulse-response and variance decomposition, making it possible to analyze the short- and long-term relationships between the time series and indicated that the different modalities of payroll loans imply different effects on economic short-term variables. With retirees and pensioners segment positively impact on both analyzed variables, highlighting the household consumption goods. The concession to the private sector, although it represents the smallest portion of payroll loans granted, it showed high sensitivity to the changes of this modality. About credit to the public sector, which has the biggest portion, it showed reduced and short-term effects.Keywords: Payroll loans. Segments. Brazilian economy.


2021 ◽  
Vol 136 (5) ◽  
Author(s):  
Andrea Basti ◽  
Nicolò Beverini ◽  
Filippo Bosi ◽  
Giorgio Carelli ◽  
Donatella Ciampini ◽  
...  

AbstractGINGERINO is one of the most sensitive Sagnac laser-gyroscopes based on an heterolithic mechanical structure. It is a prototype for GINGER, the laser gyroscopes array proposed to reconstruct the Earth rotation vector and in this way to measure General Relativity effects. Many factors affect the final sensitivity of laser gyroscopes, in particular, when they are used in long-term measurements, slow varying environmental parameters come into play. To understand the role of different terms allows to design more effective mechanical as well as optical layouts, while a proper model of the dynamics affecting long-term (low frequency) signals would increase the effectiveness of the data analysis for improving the overall sensitivity. In this contribution, we focus our concerns on the effects of room temperature and pressure aiming at further improving mechanical design and long-term stability of the apparatus. Our data are compatible with a local orientation changes of the Gran Sasso site below $$\mu $$ μ rad as predicted by geodetic models. This value is consistent with the requirements for GINGER and the installation of an high-sensitivity Sagnac gyroscope oriented at the maximum signal, i.e. along the Earth rotation axes.


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