http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Tesche, M. (검색결과 9 건)
- 무료
- 기관 내 무료
- 유료
-
TESCHE, MATTHIAS,MÜ,LLER, DETLEF,GROSS, SILKE,ANSMANN, ALBERT,ALTHAUSEN, DIETRICH,FREUDENTHALER, VOLKER,WEINZIERL, BERNADETT,VEIRA, ANDREAS,PETZOLD, ANDREAS Blackwell Publishing Ltd 2011 Tellus. Series B, Chemical and physical meteorolog Vol.63 No.4
<P><B>ABSTRACT</B></P><P>Lidar measurements of mixed dust/smoke plumes over the tropical Atlantic ocean were carried out during the winter campaign of SAMUM‐2 at Cape Verde. Profiles of backscatter and extinction coefficients, lidar ratios, and Ångström exponents related to pure biomass‐burning aerosol from southern West Africa were extracted from these observations. Furthermore, these findings were used as input for an inversion algorithm to retrieve microphysical properties of pure smoke. Seven measurement days were found suitable for the procedure of aerosol‐type separation and successive inversion of optical data that describe biomass‐burning smoke. We inferred high smoke lidar ratios of 87 ± 17 sr at 355 nm and 79 ± 17 sr at 532 nm. Smoke lidar ratios and Ångström exponents are higher compared to the ones for the dust/smoke mixture. These numbers indicate higher absorption and smaller sizes for pure smoke particles compared to the dust/smoke mixture. Inversion of the smoke data set results in mean effective radii of 0.22 ± 0.08 μm with individual results varying between 0.10 and 0.36 μm. The single‐scattering albedo for pure biomass‐burning smoke was found to vary between 0.63 and 0.89 with a very low mean value of 0.75 ± 0.07. This is in good agreement with findings of airborne in situ measurements which showed values of 0.77 ± 0.03. Effective radii from the inversion were similar to the ones found for the fine mode of the in situ size distributions.</P>
-
TESCHE, MATTHIAS,GROSS, SILKE,ANSMANN, ALBERT,MÜ,LLER, DETLEF,ALTHAUSEN, DIETRICH,FREUDENTHALER, VOLKER,ESSELBORN, MICHAEL Blackwell Publishing Ltd 2011 Tellus. Series B, Chemical and physical meteorolog Vol.63 No.4
<P><B>ABSTRACT</B></P><P>Extensive lidar measurements of Saharan dust and biomass‐burning smoke were performed with one airborne and three ground‐based instruments in the framework of the second part of the SAharan Mineral dUst experiMent (SAMUM‐2a) during January and February of 2008 at Cape Verde. Further lidar observations with one system only were conducted during May and June of 2008 (SAMUM‐2b). The active measurements were supported by Sun photometer observations. During winter, layers of mineral dust from the Sahara and biomass‐burning smoke from southern West Africa pass Cape Verde on their way to South America while pure dust layers cross the Atlantic on their way to the Caribbean during summer. The mean 500‐nm aerosol optical thickness (AOT) observed during SAMUM‐2a was 0.35 ± 0.18. SAMUM‐2a observations showed transport of pure dust within the lowermost 1.5 km of the atmospheric column. In the height range from 1.5 to 5.0 km, mixed dust/smoke layers with mean lidar ratios of 67 ± 14 sr at 355 and 532 nm, respectively, prevailed. Within these layers, wavelength‐independent linear particle depolarization ratios of 0.12–0.18 at 355, 532, and 710 nm indicate a large contribution (30–70%) of mineral dust to the measured optical properties. Ångström exponents for backscatter and extinction of around 0.7 support this finding. Mean extinction coefficients in the height range between 2 and 4 km were 66 ± 6 Mm<SUP>−1</SUP> at 355 nm and 48 ± 5 Mm<SUP>−1</SUP> at 532 nm. Comparisons with airborne high‐spectral‐resolution lidar observations show good agreement within the elevated layers. 3–5 km deep dust layers where observed during SAMUM‐2b. These layers showed optical properties similar to the ones of SAMUM‐1 in Morocco with a mean 500‐nm AOT of 0.4 ± 0.2. Dust extinction coefficients were about 80 ± 6 Mm<SUP>−1</SUP> at 355 and 532 nm. Dust lidar ratios were 53 ± 10 sr at 355 and 532 nm, respectively. Dust depolarization ratios showed an increase with wavelength from 0.31 ± 0.10 at 532 nm to 0.37 ± 0.07 at 710 nm.</P>
-
-
Li Jiahui,Wang Rui,Tesche Christian,Schoepf U. Joseph,Pannell Jonathan T.,He Yi,Huang Rongchong,Chen Yalei,Li Jianan,Song Xiantao 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.5
Objective: To investigate the feasibility and the accuracy of the coronary CT angiography (CCTA)-derived Registry of Crossboss and Hybrid procedures in France, the Netherlands, Belgium and United Kingdom (RECHARGE) score (RECHARGECCTA) for the prediction of procedural success and 30-minutes guidewire crossing in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). Materials and Methods: One hundred and twenty-four consecutive patients (mean age, 54 years; 79% male) with 131 CTO lesions who underwent CCTA before catheter angiography (CA) with CTO-PCI were retrospectively enrolled in this study. The RECHARGECCTA scores were calculated and compared with RECHARGECA and other CTA-based prediction scores, including Multicenter CTO Registry of Japan (J-CTO), CT Registry of CTO Revascularisation (CT-RECTOR), and Korean Multicenter CTO CT Registry (KCCT) scores. Results: The procedural success rate of the CTO-PCI procedures was 72%, and 61% of cases achieved the 30-minutes wire crossing. No significant difference was observed between the RECHARGECCTA score and the RECHARGECA score for procedural success (median 2 vs. median 2, p = 0.084). However, the RECHARGECCTA score was higher than the RECHARGECA score for the 30-minutes wire crossing (median 2 vs. median 1.5, p = 0.001). The areas under the curve (AUCs) of the RECHARGECCTA and RECHARGECA scores for predicting procedural success showed no statistical significance (0.718 vs. 0.757, p = 0.655). The sensitivity, specificity, positive predictive value, and the negative predictive value of the RECHARGECCTA scores of ≤ 2 for predictive procedural success were 78%, 60%, 43%, and 87%, respectively. The RECHARGECCTA score showed a discriminative performance that was comparable to those of the other CTA-based prediction scores (AUC = 0.718 vs. 0.665–0.717, all p > 0.05). Conclusion: The non-invasive RECHARGECCTA score performs better than the invasive determination for the prediction of the 30-minutes wire crossing of CTO-PCI. However, the RECHARGECCTA score may not replace other CTA-based prediction scores for predicting CTO-PCI success.
-
Shin, Sung-Kyun,Tesche, Matthias,Kim, Kwanchul,Kezoudi, Maria,Tatarov, Boyan,Mü,ller, Detlef,Noh, Youngmin Copernicus GmbH 2018 Atmospheric Chemistry and Physics Vol.18 No.17
<P>Abstract. Knowledge of the particle lidar ratio (Sλ) and the particle linear depolarisation ratio (δλ) for different aerosol types allows for aerosol typing and aerosol-type separation in lidar measurements. Reference values generally originate from dedicated lidar observations but might also be obtained from the inversion of AErosol RObotic NETwork (AERONET) sun/sky radiometer measurements. This study investigates the consistency of spectral Sλ and δλ provided in the recently released AERONET version 3 inversion product for observations of undiluted mineral dust in the vicinity of the following major deserts: Gobi, Sahara, Arabian, Great Basin, and Great Victoria. Pure dust conditions are identified by an Ångström exponent <0.4 and a fine-mode fraction <0.1. The values of spectral Sλ are found to vary for the different source regions but generally show an increase with decreasing wavelength. The feature correlates to AERONET, retrieving an increase in the imaginary part of the refractive index with decreasing wavelength. The smallest values of Sλ=35-45 sr are found for mineral dust from the Great Basin desert, while the highest values of 50-70 sr have been inferred from AERONET observations of Saharan dust. Values of Sλ at 675, 870, and 1020 nm seem to be in reasonable agreement with available lidar observations, while those at 440 nm are up to 10 sr higher than the lidar reference. The spectrum of δλ shows a maximum of 0.26-0.31 at 1020 nm and decreasing values as wavelength decreases. AERONET-derived δλ values at 870 and 1020 nm are in line with the lidar reference, while values of 0.19-0.24 at 440 nm are smaller than the independent lidar observations by a difference of 0.03 to 0.08. This general behaviour is consistent with earlier studies based on AERONET version 2 products. </P>
-
-
Chun Xiang Tang,Meng Jie Lu,Joseph Uwe Schoepf,Christian Tesche,Maximilian Bauer,John Nance,Parkwood Griffith,Guang Ming Lu,Long Jiang Zhang 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.2
Objective: To examine the fractional flow reserve derived from computed tomographic angiography (CT-FFR) in patients with anomalous origin of the right coronary artery from the left coronary sinus (R-ACAOS) with an interarterial course, assess the relationship of CT-FFR with the anatomical features of interarterial R-ACAOS on coronary computed tomographic angiography (CCTA), and determine its clinical relevance. Materials and Methods: Ninety-four patients with interarterial R-ACAOS undergoing CCTA were retrospectively included. Anatomic features (proximal vessel morphology [oval or slit-like], take-off angle, take-off level [below or above the pulmonary valve], take-off type, intramural course, % proximal narrowing area, length of narrowing, minimum luminal area [MLA] at systole and diastole, and vessel compression index) on CCTA associated with CT-FFR ≤ 0.80 were analyzed. Receiver operating characteristic analysis was performed to describe the diagnostic performance of CT-FFR ≤ 0.80 in detecting interarterial R-ACAOS. Results: Significant differences were found in proximal vessel morphology, take-off level, intramural course, % proximal narrowing area, and MLA at diastole (all p < 0.05) between the normal and abnormal CT-FFR groups. Take-off level, intramural course, and slit-like ostium (all p < 0.05) predicted hemodynamic abnormality (CT-FFR ≤ 0.80) with accuracies of 0.69, 0.71, and 0.81, respectively. Patients with CT-FFR ≤ 0.80 had a higher prevalence of typical angina (29.4% vs. 7.8%, p = 0.025) and atypical angina (29.4% vs. 6.5%, p = 0.016). Conclusion: Take-off level, intramural course, and slit-like ostium were the main predictors of abnormal CT-FFR values. Importantly, patients with abnormal CT-FFR values showed a higher prevalence of typical angina and atypical angina, indicating that CT-FFR is a potential tool to gauge the clinical relevance in patients with interarterial R-ACAOS.
-
Volcanic aerosol layers observed with multiwavelength Raman lidar over central Europe in 2008-2009
Mattis, Ina,Siefert, Patric,Mü,ller, Detlef,Tesche, Matthias,Hiebsch, Anja,Kanitz, Thomas,Schmidt, Jö,rg,Finger, Fanny,Wandinger, Ulla,Ansmann, Albert American Geophysical Union 2010 Journal of Geophysical Research Vol.115 No.d2
<P>In the framework of regular European Aerosol Research Lidar Network (EARLINET) observations, aerosol layers have been monitored with a multiwavelength aerosol Raman lidar in the upper troposphere and lower stratosphere over Leipzig (51.4 degrees N, 12.4 degrees E), Germany, since the summer of 2008. The origins of these layers are eruptions of different volcanoes on the Aleutian Islands, Kamchatka, Alaska, and on the Kuril Islands. FLEXPART transport simulations show that the volcanic aerosol is advected from Alaska to central Europe within about 7 days. The aerosol layers typically occurred in the upper troposphere above 5 km height and in the lower stratosphere below 25 km height. The optical depths of the volcanic aerosol layers are mostly between 0.004 and 0.025 at 532 nm. The wavelength dependence of the backscatter coefficients and extinction coefficients indicate Angstrom exponents from 1.0-2.0. Lidar ratios in the stratosphere are found in the range from 30-60 sr (355 nm) and 30-45 sr (532 nm). The estimation of the effective radius, surface-area, and mass concentrations of a volcanic aerosol layer, observed well within the stratosphere at end of August 2009, reveals values of 0.1-0.2 mu m, 5-10 mu m(2) cm(-3), and 0.3-0.5 mu g m(-3), respectively.</P>
-
It is all me: the effect of viewpoint on visual-vestibular recalibration.
Schomaker, Judith,Tesch, Joachim,B?lthoff, Heinrich H,Bresciani, Jean-Pierre Springer-Verlag 2011 Experimental brain research Vol.213 No.2
<P>Participants performed a visual-vestibular motor recalibration task in virtual reality. The task consisted of keeping the extended arm and hand stable in space during a whole-body rotation induced by a robotic wheelchair. Performance was first quantified in a pre-test in which no visual feedback was available during the rotation. During the subsequent adaptation phase, optical flow resulting from body rotation was provided. This visual feedback was manipulated to create the illusion of a smaller rotational movement than actually occurred, hereby altering the visual-vestibular mapping. The effects of the adaptation phase on hand stabilization performance were measured during a post-test that was identical to the pre-test. Three different groups of subjects were exposed to different perspectives on the visual scene, i.e., first-person, top view, or mirror view. Sensorimotor adaptation occurred for all three viewpoint conditions, performance in the post-test session showing a marked under-compensation relative to the pre-test performance. In other words, all viewpoints gave rise to a remapping between vestibular input and the motor output required to stabilize the arm. Furthermore, the first-person and mirror view adaptation induced a significant decrease in variability of the stabilization performance. Such variability reduction was not observed for the top view adaptation. These results suggest that even if all three viewpoints can evoke substantial adaptation aftereffects, the more naturalistic first-person view and the richer mirror view should be preferred when reducing motor variability constitutes an important issue.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
