Journal articles: 'Ipda'

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Tomimaru, Yoshito, Kaishu Tanaka, Kozo Noguchi, Shunji Morita, Hiroshi Imamura, and Keizo Dono. "The Branching Pattern of the Inferior Pancreaticoduodenal Artery in Patients with a Replaced Right Hepatic Artery." American Surgeon 84, no. 6 (June 2018): 796–800. http://dx.doi.org/10.1177/000313481808400621.

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Understanding the anatomy of the inferior pancreaticoduodenal artery (IPDA) is important in patients undergoing pancreaticoduodenectomy, especially in an artery-first approach, resulting in some studies focusing on IPDA anatomy. However, the studies have covered only cases without variation in hepatic arterial anatomy, a common arterial variant, suggesting the necessity of the investigation of IPDA anatomy in cases with the variant. Using images of multidetector row computed tomography, cases with replaced right hepatic artery (rRHA) were picked out among 714 patients undergoing multidetector row computed tomography for determining arteries of the pancreatic head at our institution. IPDA branching pattern was investigated in the rRHA cases. Three-dimensional reconstruction was performed to visually understand the branching pattern in representative cases. rRHA was identified in 139 cases (19.5%); rRHA originating from the superior mesenteric artery (SMA) (type 1; 74.1%), celiac axis (type 2; 18.0%), and others (type 3; 7.9%). IPDA branching pattern was categorized; IPDA originated from SMA (type A), posterior and anterior IPDA originated from rRHA and SMA, respectively (type B), or IPDA originated from rRHA (type C). Of type 1 cases, 69, 23, and 11 cases showed type A, B, and C pattern, respectively. Of type 2 cases, 16 and 9 cases showed type A and B, respectively. All 11 type 3 cases showed type C. IPDA branching pattern was determined in the rRHA cases. This would help identification of rRHA cases where the artery-first approach is technically less feasible at pancreaticoduodenectomy (type 1-B, 1-C, and 2-B).

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Refaat, Tamer F., Upendra N. Singh, Jirong Yu, Mulugeta Petros, Ruben Remus, and Syed Ismail. "Airborne Two-Micron Double-Pulse IPDA Lidar Validation for Carbon Dioxide Measurements Over Land." EPJ Web of Conferences 176 (2018): 05001. http://dx.doi.org/10.1051/epjconf/201817605001.

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An airborne double-pulse 2-μm Integrated Path Differential Absorption (IPDA) lidar has been developed at NASA LaRC for measuring atmospheric CO2. IPDA was validated using NASA B-200 aircraft over land and ocean under different conditions. IPDA evaluation for land vegetation returns, during full day background conditions, are presented. IPDA CO2 measurements compare well with model results driven from on-board insitu sensor data. These results also indicate that CO2 measurement bias is consistent with that from ocean surface returns.

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Yu, Jirong, Mulugeta Petros, Upendra Singh, Tamer Refaat, Karl Reithmaier, Ruben Remus, and William Johnson. "Flight Demonstration of a 2-Micron, Double Plused CO2 IPDA Lidar Instrument." EPJ Web of Conferences 237 (2020): 03013. http://dx.doi.org/10.1051/epjconf/202023703013.

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NASA Langley Research Center (LaRC) developed a double pulsed, high energy 2-micron Integrated Path Differential Absorption (IPDA) lidar instrument to measure atmospheric CO2 column density. The 2-μm double pulsed IPDA lidar was flown ten times in March and April of 2014. It was determined that the IPDA lidar measurement is in good agreement with an in-situ CO2 measurement by a collocated NOAA flight. The average column CO2 density difference between the IPDA lidar measurements and the NOAA air samples is 1.48ppm in the flight altitudes of 3 to 6.1 km.

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Funkhouser, William K., D. Neil Hayes, Dominic T. Moore, W. Keith Funkhouser, Jason P. Fine, HeeJoon Jo, Nana Nikolaishvilli-Feinberg, et al. "Interpathologist Diagnostic Agreement for Non–Small Cell Lung Carcinomas Using Current and Recent Classifications." Archives of Pathology & Laboratory Medicine 142, no. 12 (April 30, 2018): 1537–48. http://dx.doi.org/10.5858/arpa.2017-0481-oa.

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Context.— Measurement of interpathologist diagnostic agreement (IPDA) should allow pathologists to improve current diagnostic criteria and disease classifications. Objectives.— To determine how IPDA for pathologists' diagnoses of non–small cell lung carcinoma (NSCLC) is affected by the addition of a set of mucin and immunohistochemical (IHC) stains to hematoxylin-eosin (H&E) alone, by recent NSCLC reclassifications, by simplification of these classifications, and by pathologists' practice location, pulmonary pathology expertise, practice duration, and lung carcinoma case exposure. Design.— We used a Web-based survey to present core images of 54 NSCLC cases to 22 practicing pathologists for diagnosis, initially as H&E only, then as H&E plus mucin and 4 IHC stains. Each case was diagnosed according to published 2004, 2011, and 2015 NSCLC classifications. Cohen's kappa was calculated for the 231 pathologist pairs as a measure of IPDA. Results.— Twenty-two pathologists diagnosed 54 NSCLC cases by using 4 published classifications. IPDA is significantly higher for H&E/mucin/IHC diagnoses than for H&E-only diagnoses. IPDA for H&E/mucin/IHC diagnoses is highest with the 2015 classification. IPDA is estimated higher after collapse of stated diagnoses into subhead or dichotomized classes. IPDA for H&E/mucin/IHC diagnoses with the 2015 World Health Organization classification is similar for community and academic pathologists, and is higher when pathologists have pulmonary pathology expertise, have more than 6 years of practice experience, or diagnose more than 100 new lung carcinoma cases per year. Conclusions.— Higher IPDA is associated with use of mucin and IHC stains, with the 2015 NSCLC classification, and with pathologists' pulmonary pathology expertise, practice duration, and frequency of lung carcinoma cases.

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Bethke, Christian, Sebastian Manfred Goller, Uy Lan Du Ngoc, Simon Tino Kaysser, Volker Altstädt, and Holger Ruckdäschel. "Tailoring Epoxy Resin Foams by Pre-Curing with Neat Amine Hardeners and Its Derived Carbamates." Polymers 13, no. 8 (April 20, 2021): 1348. http://dx.doi.org/10.3390/polym13081348.

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The use of amine-based carbamates with their dual function, acting as amine curing agents and CO2 blowing agents after their decomposition without by-products, are promising for ecofriendly epoxy foams as high-performance materials. However, controlling cell morphology requires a proper adjustment of the viscosity at the foaming step. The viscosity is altered not only by blending neat amine and its derived carbamate at a fixed pre-curing time, but also by changing the pre-curing time at a fixed blend ratio. Within this study, diglycidylether of bisphenol A (DGEBA) epoxy resin is mixed with different blend ratios of isophorone diamine (IPDA) and its derived carbamate (B-IPDA). The systems are characterized by DSC and rheology experiments to identify the pre-curing effects on the derived epoxy foams. Epoxy foams at a blend ratio of 30/70w IPDA/B-IPDA showed the best foam morphology and an optimum Tg compared to other blend ratios. Furthermore, it was found that both pre-curing times, 2 h and 3 h, for the 30/70w IPDA/B-IPDA system reveal a more homogeneous cell structure. The study proves that the blending of neat amine and carbamate is beneficial for the foaming performance of carbamate systems.

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Rao, G. "Welcome to the iPDA!" PDA Journal of Pharmaceutical Science and Technology 65, no. 5 (September 1, 2011): 431. http://dx.doi.org/10.5731/pdajpst.2011.00816.

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Klonaris, Chris, Emmanouil Psathas, Athanasios Katsargyris, Stella Lioudaki, Achilleas Chatziioannou, and Theodore Karatzas. "Multiple Aneurysms of the Inferior Pancreaticoduodenal Artery: A Rare Complication of Acute Pancreatitis." Case Reports in Vascular Medicine 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/621350.

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Inferior pancreaticoduodenal artery (IPDA) aneurysms are uncommon, representing nearly 2% of all visceral aneurysms, and sporadically associated with celiac artery stenosis. Multiple IPDA aneurysms have been rarely reported. We report a case of a 53-year-old female patient with a history of prior pancreatitis, who presented with two IPDA aneurysms combined with median arcuate ligament-syndrome-like stenosis of the celiac trunk. The patient was treated successfully with coil embolization under local anesthesia. The procedure is described and illustrated in detail and the advantages and technical considerations of such an approach are also being discussed.

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Yu, Jirong, Mulugeta Petros, Upendra N. Singh, Tamer F. Refaat, Karl Reithmaier, Ruben G. Remus, and William Johnson. "An Airborne 2-μm Double-Pulsed Direct-Detection Lidar Instrument for Atmospheric CO2 Column Measurements." Journal of Atmospheric and Oceanic Technology 34, no. 2 (February 2017): 385–400. http://dx.doi.org/10.1175/jtech-d-16-0112.1.

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AbstractThis study reports airborne measurements of atmospheric CO2 column density using a 2-μm double-pulsed integrated path differential absorption (IPDA) lidar. This new 2-μm IPDA lidar offers an alternative approach to measure CO2 column density with unique features. The online frequencies of this lidar can be tuned to 1–6 GHz from the CO2 R30 absorption line peak. It provides high measurement sensitivity to the lower-tropospheric CO2 near the ground surface. This instrument was flown in the spring of 2014 in a NASA B200 aircraft. The results of these test flights clearly demonstrate the measurement capabilities of this lidar instrument. The CO2 column dry mixing ratio is compared to an in situ CO2 measurement by a collocated NOAA flight. The IPDA lidar measurement is determined to be in good agreement with a 0.36% difference, which corresponds to 1.48 ppm. It is the average difference between the IPDA lidar measurements and the NOAA air samples in the flight altitudes from 3 to 6.1 km.

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Su, C. T., C. Y. Chen, and C. M. Hsu. "iPDA: integrated protein disorder analyzer." Nucleic Acids Research 35, Web Server (May 8, 2007): W465—W472. http://dx.doi.org/10.1093/nar/gkm353.

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Han, Ge, Tianqi Shi, Xin Ma, Hao Xu, Miao Zhang, Qi Liu, and Wei Gong. "Obtaining Gradients of XCO2 in Atmosphere Using the Constrained Linear Least-Squares Technique and Multi-Wavelength IPDA LiDAR." Remote Sensing 12, no. 15 (July 25, 2020): 2395. http://dx.doi.org/10.3390/rs12152395.

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Integrated-path differential absorption (IPDA) LiDAR is a promising means of measuring the global distributions of the column weighted xCO2 (dry-air mixing ratio of CO2) with adequate accuracy and precision. Most IPDA LiDARs are incapable of discerning the vertical information of CO2 diffusion, which is of great significance for studies on the carbon cycle and climate change. Hence, we developed an inversion method using the constrained linear least-squares technique for a pulsed direct-detection multi-wavelength IPDA LiDAR to obtain sliced xCO2. In the proposed inversion method, the atmosphere is sliced into three different layers, and the xCO2 of those layers is then retrieved using the constrained linear least-squares technique. Assuming complete knowledge of the water vapor content, the accuracy of the retrieved sliced xCO2 could be as high as 99.85% when the signal-to-noise ratio of central wavelength retrievals is higher than 25 (with a log scale). Further experiments demonstrated that different carbon characteristics can be identified by the sign of the carbon gradient of the retrieved xCO2 between the ABL (atmospheric boundary layer) and FT (free troposphere). These results highlight the potential applications of multiple wavelength IPDA LiDAR.

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Simonetti, Francesco R., Jennifer A. White, Camille Tumiotto, Kristen D. Ritter, Mian Cai, Rajesh T. Gandhi, Steven G. Deeks, et al. "Intact proviral DNA assay analysis of large cohorts of people with HIV provides a benchmark for the frequency and composition of persistent proviral DNA." Proceedings of the National Academy of Sciences 117, no. 31 (July 20, 2020): 18692–700. http://dx.doi.org/10.1073/pnas.2006816117.

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A scalable approach for quantifying intact HIV-1 proviruses is critical for basic research and clinical trials directed at HIV-1 cure. The intact proviral DNA assay (IPDA) is a novel approach to characterizing the HIV-1 reservoir, focusing on the genetic integrity of individual proviruses independent of transcriptional status. It uses multiplex digital droplet PCR to distinguish and separately quantify intact proviruses, defined by a lack of overt fatal defects such as large deletions and APOBEC3G-mediated hypermutation, from the majority of proviruses that have such defects. This distinction is important because only intact proviruses cause viral rebound on ART interruption. To evaluate IPDA performance and provide benchmark data to support its implementation, we analyzed peripheral blood samples from 400 HIV-1+adults on ART from several diverse cohorts, representing a robust sample of treated HIV-1 infection in the United States. We provide direct quantitative evidence that defective proviruses greatly outnumber intact proviruses (by >12.5 fold). However, intact proviruses are present at substantially higher frequencies (median, 54/106CD4+T cells) than proviruses detected by the quantitative viral outgrowth assay, which requires induction and in vitro growth (∼1/106CD4+T cells). IPDA amplicon signal issues resulting from sequence polymorphisms were observed in only 6.3% of individuals and were readily apparent and easily distinguished from low proviral frequency, an advantage of the IPDA over standard PCR assays which generate false-negative results in such situations. The large IPDA dataset provided here gives the clearest quantitative picture to date of HIV-1 proviral persistence on ART.

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Wang, Shuaibo, Ju Ke, Sijie Chen, Zhuofan Zheng, Chonghui Cheng, Bowen Tong, Jiqiao Liu, Dong Liu, and Weibiao Chen. "Performance Evaluation of Spaceborne Integrated Path Differential Absorption Lidar for Carbon Dioxide Detection at 1572 nm." Remote Sensing 12, no. 16 (August 10, 2020): 2570. http://dx.doi.org/10.3390/rs12162570.

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As one of the most influential greenhouse gases, carbon dioxide (CO2) has a profound impact on the global climate. The spaceborne integrated path differential absorption (IPDA) lidar will be a great sensor to obtain the columnar concentration of CO2 with high precision. This paper analyzes the performance of a spaceborne IPDA lidar, which is part of the Aerosol and Carbon Detection Lidar (ACDL) developed in China. The line-by-bine radiative transfer model was used to calculate the absorption spectra of CO2 and H2O. The laser transmission process was simulated and analyzed. The sources of random and systematic errors of IPDA lidar were quantitatively analyzed. The total systematic errors are 0.589 ppm. Monthly mean global distribution of relative random errors (RREs) was mapped based on the dataset in September 2016. Afterwards, the seasonal variations of the global distribution of RREs were studied. The global distribution of pseudo satellite measurements for a 16-day orbit repeat cycle showed relatively uniform distribution over the land of the northern hemisphere. The results demonstrated that 61.24% of the global RREs were smaller than 0.25%, or about 1 ppm, while 2.76% of the results were larger than 0.75%. The statistics reveal the future performance of the spaceborne IPDA lidar.

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Refaat, Tamer F., Mulugeta Petros, Charles W. Antill, Upendra N. Singh, Yonghoon Choi, James V. Plant, Joshua P. Digangi, and Anna Noe. "Airborne Testing of 2-μm Pulsed IPDA Lidar for Active Remote Sensing of Atmospheric Carbon Dioxide." Atmosphere 12, no. 3 (March 23, 2021): 412. http://dx.doi.org/10.3390/atmos12030412.

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The capability of an airborne 2-μm integrated path differential absorption (IPDA) lidar for high-accuracy and high-precision active remote sensing of weighted-average column dry-air volume mixing ratio of atmospheric carbon dioxide (XCO2) is demonstrated. A test flight was conducted over the costal oceanic region of the USA to assess instrument performance during severe weather. The IPDA targets CO2 R30 absorption line using high-energy 2-μm laser transmitter. HgCdTe avalanche photodiode detection system is used in the receiver. Updated instrument model included range correction factor to account for platform attitude. Error budget for XCO2 retrieval predicts lower random error for longer sensing column length. Systematic error is dominated by water vapor (H2O) through dry-air number density derivation, followed by H2O interference and ranging related uncertainties. IPDA XCO2 retrieval results in 404.43 ± 1.23 ppm, as compared to 405.49 ± 0.01 ppm from prediction models, using consistent reflectivity and steady elevation oceanic surface target. This translates to 0.26% and 0.30% relative accuracy and precision, respectively. During gradual spiral descend, IPDA results in 404.89 ± 1.19 ppm as compared model of 404.75 ± 0.73 ppm indicating 0.04% and 0.23% relative accuracy, respectively. Challenging cloud targets limited retrieval accuracy and precision to 2.56% and 4.78%, respectively, due to H2O and ranging errors.

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Shah, Ghawas Ali, Sumair Khan, Sufyan Ali Memon, Mohsin Shahzad, Zahid Mahmood, and Uzair Khan. "Improvement in the Tracking Performance of a Maneuvering Target in the Presence of Clutter." Sensors 22, no. 20 (October 16, 2022): 7848. http://dx.doi.org/10.3390/s22207848.

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The proposed work uses fixed lag smoothing on the interactive multiple model-integrated probabilistic data association algorithm (IMM-IPDA) to enhance its performance. This approach makes use of the advantages of the fixed lag smoothing algorithm to track the motion of a maneuvering target while it is surrounded by clutter. The suggested method provides a new mathematical foundation in terms of smoothing for mode probabilities in addition to the target trajectory state and target existence state by including the smoothing advantages. The suggested fixed lag smoothing IMM-IPDA (FLs IMM-IPDA) method’s root mean square error (RMSE), true track rate (TTR), and mode probabilities are compared to those of other recent algorithms in the literature in this study. The results clearly show that the proposed algorithm outperformed the already-known methods in the literature in terms of these above parameters of interest.

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Amediek, Axel, Gerhard Ehret, Andreas Fix, Martin Wirth, Christian Büdenbender, Mathieu Quatrevalet, and Christoph Kiemle. "Performance of Charm-F – the airborne demonstrator for Merlin." EPJ Web of Conferences 176 (2018): 01002. http://dx.doi.org/10.1051/epjconf/201817601002.

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In 2015, the new airborne lidar CHARM-F for the measurement of the greenhouse gases carbon dioxide and methane was set into operation. It is an integrated path differential absorption (IPDA) lidar designed for the use onboard the German research aircraft HALO. Due to its high technological similarity to the MERLIN space lidar, it is also a demonstrator for the space system. Here, we report on CHARM-F’s technology, the experiences with the IPDA lidar method and the achieved performance.

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Petros, Mulugeta, Tamer F. Refaat, Upendra N. Singh, Jirong Yu, Charles Antill, Ruben Remus, Bryant D. Taylor, et al. "Development of an advanced Two-Micron triple-pulse IPDA lidar for carbon dioxide and water vapor measurements." EPJ Web of Conferences 176 (2018): 01009. http://dx.doi.org/10.1051/epjconf/201817601009.

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An advanced airborne triple-pulse 2-μm integrated path differential absorption (IPDA) lidar is under development at NASA Langley Research Center that targets both carbon dioxide (CO2) and water vapor (H2O) measurements simultaneously and independently. This lidar is an upgrade to the successfully demonstrated CO2 2-μm double-pulse IPDA. Upgrades include high-energy, highrepetition rate 2-μm triple-pulse laser transmitter, innovative wavelength control and advanced HgCdTe (MCT) electron-initiated avalanche photodiode detection system. Ground testing and airborne validation plans are presented.

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Owens, Mandy D., and William H. Zywiak. "Replication of psychometric properties and predictive validity of the Important People Drug and Alcohol Interview." International Journal of Alcohol and Drug Research 5, no. 2 (July 15, 2016): 57–64. http://dx.doi.org/10.7895/ijadr.v5i2.217.

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Owens, M., & Zywiak, W. (2016). Replication of psychometric properties and predictive validity of the Important People Drug and Alcohol Interview. The International Journal Of Alcohol And Drug Research, 5(2), 57-64. doi:http://dx.doi.org/10.7895/ijadr.v5i2.217Aims: Social support is a predictor of alcohol and drug use. The Important People Drug and Alcohol (IPDA) interview and its predecessor, the Important People and Activities (IPA) measure, have been used to demonstrate this predictive relationship. The purpose of this study was to replicate the findings from Zywiak et al. (2009) in a sample of probationers with substance use disorders.Design: Analyses mirrored those done previously to replicate the associations between social networks and substance use. The IPDA was used to assess social networks before and after incarceration. Form-90 (Tonigan, Miller, & Brown, 1997) was used to measure substance use.Participants: Individuals were recruited from a local probation office. Information was collected from a sample of 50 male probationers with substance use disorders recently released from jail.Conclusions: Results showed that many of the previous findings from Zywiak et al. (2009) were similar to those found in the current study. This adds to the evidence that the IPDA is a promising measure of social networks and examining how those networks relate to substance use outcomes. The use of the IPDA may be beneficial for both research and clinical purposes, while evaluating individuals with alcohol and other drug use disorders.

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Ferreira, Álida Rosária Silva, and Laura Rodrigues Wong. "Cuidadores informais da população idosa com alguma limitação:." SER Social, no. 21 (August 14, 2009): 71–104. http://dx.doi.org/10.26512/ser_social.v0i21.12736.

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O envelhecimento da população, oriundo da queda da fecundidade e da maior longevidade, faz com que, no futuro, o grupo das pessoas disponíveis para o cuidado de idosos necessitados de assistência seja cada vez menor. Este artigo analisa o perfil do potencial cuidador informal de idosos no Brasil e estima o contingente de ambos: o idoso que potencialmente demanda assistência (IPDA) e o potencial cuidador informal (PCI). O mapeamento do Censo Demográfico de 2000 indica a existência de cerca de 7,5 milhões de pessoas de 60 e mais anos com algum grau de incapacidade e, morando com eles, pouco mais de 8 milhões de pessoas entre 18 a 79 anos sem limitações físicas. Isso gera uma razão de quase um PCI para cada IPDA. Dados qualitativos permitem captar características mais definidas de cuidadores informais, sendo as mais relevantes a presença de sentimentos de obrigação, gratidão e culpa. A união dos enfoques qualitativos/quantitativos permitiu construir cenários de demanda e oferta dos PCI, estimar a evolução do volume do PCI no período entre 2000 e 2015 e compará-la com a evolução dos IPDA. No médio prazo, essas simulações indicam diminuição do estoque de potenciais cuidadores.

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Han, Ge, Xin Ma, Ailin Liang, Tianhao Zhang, Yannan Zhao, Miao Zhang, and Wei Gong. "Performance Evaluation for China’s Planned CO2-IPDA." Remote Sensing 9, no. 8 (July 26, 2017): 768. http://dx.doi.org/10.3390/rs9080768.

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Nikolov, Susanne, Christian Wührer, Christopher Kühl, Markus Bode, Werner Hupfer, and Stefano Lucarelli. "MERLIN: design of an IPDA LIDAR instrument." CEAS Space Journal 11, no. 4 (August 23, 2019): 437–57. http://dx.doi.org/10.1007/s12567-019-00267-7.

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Song, Taek Lyul, and Darko Mušicki. "Smoothing innovations and data association with IPDA." Automatica 48, no. 7 (July 2012): 1324–29. http://dx.doi.org/10.1016/j.automatica.2012.04.001.

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Zhu, Yadan, Juxin Yang, Xiao Chen, Xiaopeng Zhu, Junxuan Zhang, Shiguang Li, Yanguang Sun, et al. "Airborne Validation Experiment of 1.57-μm Double-Pulse IPDA LIDAR for Atmospheric Carbon Dioxide Measurement." Remote Sensing 12, no. 12 (June 22, 2020): 1999. http://dx.doi.org/10.3390/rs12121999.

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The demand for greenhouse gas measurement has increased dramatically due to global warming. A 1.57-μm airborne double-pulse integrated-path differential absorption (IPDA) light detection and ranging (LIDAR) system for CO2 concentration measurement was developed. The airborne field experiments of this IPDA LIDAR system were conducted at a flight altitude of approximately 7 km, and the weak echo signal of the ocean area was successfully received. The matched filter algorithm was applied to the retrieval of the weak signals, and the pulse integration method was used to improve the signal-to-noise ratio. The inversion results of the CO2 column-averaged dry-air mixing ratio (XCO2) by the scheme of averaging after log (AVD) and the scheme of averaging signals before log were compared. The AVD method was found more effective for the experiment. The long-term correlation between the changing trends of XCO2 retrieved by the IPDA LIDAR system and CO2 dry-air volume mixing ratio measured by the in-situ instrument reached 92%. In the steady stage of the open area (30 km away from the coast), which is almost unaffected by the residential areas, the mean value of XCO2 retrieved by the IPDA LIDAR system was 414.69 ppm, with the standard deviation being 1.02 ppm. Compared with the CO2 concentration measured by the in-situ instrument in the same period, bias was 1.30 ppm. The flight path passed across the ocean, residential, and mountainous areas, with the mean value of XCO2 of the three areas being 419.35, 429.29, and 422.52 ppm, respectively. The gradient of the residential and ocean areas was 9.94 ppm, with that of the residential and mountainous areas being 6.77 ppm. Obvious gradients were found in different regions.

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Zhu, Yadan, Juxin Yang, Xiaoxi Zhang, Jiqiao Liu, Xiaopeng Zhu, Huaguo Zang, Tengteng Xia, et al. "Performance Improvement of Spaceborne Carbon Dioxide Detection IPDA LIDAR Using Linearty Optimized Amplifier of Photo-Detector." Remote Sensing 13, no. 10 (May 20, 2021): 2007. http://dx.doi.org/10.3390/rs13102007.

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The spaceborne double-pulse integrated-path differential absorption (IPDA) light detection and ranging (LIDAR) system was found to be helpful in observing atmospheric CO2 and understanding the carbon cycle. The airborne experiments of a scale prototype of China’s planned spaceborne IPDA LIDAR was implemented in 2019. A problem with data inversion caused by the detector module nonlinearity was found. Through many experiments, the amplifier circuit board (ACB) of the detector module was proved to be the main factor causing the nonlinearity. Through amplifier circuit optimization, the original bandwidth of the ACB was changed to 1 MHz by using a fifth-order active filter. Compared with the original version, the linearity of optimized ACB is improved from 42.6% to 0.0747%. The optimized ACB was produced and its linearity was verified by experiments. In addition, the output waveform of the optimized ACB changes significantly, which will affect the random error (RE) of the optimized IPDA LIDAR system. Through the performance simulation, the RE of more than 90% of the global area is less than 0.728 ppm. Finally, the transfer model of the detector module was given, which will be helpful for the further optimization of the CO2 column-averaged dry-air mixing ratio (XCO2) inversion algorithm.

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Musicki, D., and S. Suvorova. "Tracking in clutter using IMM-IPDA-based algorithms." IEEE Transactions on Aerospace and Electronic Systems 44, no. 1 (January 2008): 111–26. http://dx.doi.org/10.1109/taes.2008.4516993.

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Liang, Xindong, Hao Liu, Tao Chen, Wei Kong, and Guanglie Hong. "Calibration and Improved Speckle Statistics of IM-CW Lidar for Atmospheric CO2 Measurements." Atmosphere 11, no. 7 (July 11, 2020): 737. http://dx.doi.org/10.3390/atmos11070737.

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An intensity modulated, continuous-wave (IM-CW) integrated path differential absorption (IPDA) fiber-based lidar is developed herein for measuring atmospheric carbon dioxide (CO2). There are two main challenges in improving measurement accuracy, which have not been given enough attention in the previous research: one is that temperature sensitivity in optical components causes biases, due to the drift of component characteristic, and the other is that speckle noise deteriorates the signal-to-noise ratio. With the components thermally controlled, a target calibration accuracy of 0.003 dB is realized, corresponding to a CO2 concentration precision of better than 1 ppm for a 1 km path. A moving diffuser can reduce speckle noise by time averaging. In this paper, movement of the diffuser is substituted by the perturbation of the emitted laser beam by using a vibrating motor mounted on the optical antenna. Selecting on and off wavelengths with a small wavelength separation can improve the correlation between two laser speckle fields. These improvements result in the improved accuracy of the IPDA lidar system. Finally, the lidar performance was analyzed after the improvements described above were implemented. The diurnal variations of the atmospheric CO2 concentration using a topographic target were performed, and the results showed good agreement with the data measured by an in situ sensor. The root mean square (rms) of the deviation between the IPDA lidar and the in situ sensor was less than 1.4%.

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Kopperundevi, V., Joyce Prabhakar, Samarthan S. L., and R. Kannan. "A rare case of pseudoaneurysm of posterior inferior pancreaticoduodenal artery related with hemosuccus pancreaticus: a case report." International Surgery Journal 9, no. 3 (February 28, 2022): 684. http://dx.doi.org/10.18203/2349-2902.isj20220645.

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Hemosuccus pancreaticus is a rare cause of obscure and intermittent upper GI bleeding, often life threatening. Usually seen in a patient with chronic alcoholic pancreatitis complicated with pseudoaneurysm of splenic artery in most of the cases. In the given case reports it was pseudoaneurysm of the posterior branch of inferior pancreaticoduodenal artery (IPDA) which accounts for less than 0.07% of total 10% of pseudoaneurysm of visceral arteries caused by hemosuccus pancreaticus. These patients usually present with an obscure moderate upper GI bleed. Early clinical, endoscopic and radiological diagnosis helps to determine the appropriate method of management. Most of the cases require the endovascular interventions like glue embolisation or metal coiling or beads, very few cases end up with explorative laparotomy. Here we report a rare case presentation of upper GI bleed due to pseudoaneurysm of IPDA in hemosuccus pancreaticus, it’s diagnosis and management.

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Ishii, S., M. Koyama, P. Baron, H. Iwai, K. Mizutani, T. Itabe, A. Sato, and K. Asai. "Ground-based integrated path coherent differential absorption lidar measurement of CO<sub>2</sub>: foothill target return." Atmospheric Measurement Techniques 6, no. 5 (May 23, 2013): 1359–69. http://dx.doi.org/10.5194/amt-6-1359-2013.

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Abstract. The National Institute of Information and Communications Technology (NICT) has made a great deal of effort to develop a coherent 2 μm differential absorption and wind lidar (Co2DiaWiL) for measuring CO2 and wind speed. First, coherent Integrated Path Differential Absorption (IPDA) lidar experiments were conducted using the Co2DiaWiL and a foothill target (tree and ground surface) located about 7.12 km south of NICT on 11, 27, and 28 December 2010. The detection sensitivity of a 2 μm IPDA lidar was examined in detail using the CO2 concentration measured by the foothill reflection. The precisions of CO2 measurements for the foothill target and 900, 4500 and 27 000 shot pairs were 6.5, 2.8, and 1.2%, respectively. The results indicated that a coherent IPDA lidar with a laser operating at a high pulse repetition frequency of a few tens of KHz is necessary for XCO2 (column-averaged dry air mixing ratio of CO2) measurement with a precision of 1–2 ppm in order to observe temporal and spatial variations in the CO2. Statistical comparisons indicated that, although a small amount of in situ data and the fact that they were not co-located with the foothill target made comparison difficult, the CO2 volume mixing ratio obtained by the Co2DiaWiL measurements for the foothill target and atmospheric returns was about −5 ppm lower than the 5 min running averages of the in situ sensor. Not only actual difference of sensing volume or the natural variability of CO2 but also the fluctuations of temperature could cause this difference. The statistical results indicated that there were no biases between the foothill target and atmospheric return measurements. The 2 μm coherent IPDA lidar can detect the CO2 volume mixing ratio change of 3% in the 5 min signal integration. In order to detect the position of the foothill target, to measure a range with a high SNR (signal-to-noise ratio), and to reduce uncertainty due to the presence of aerosols and clouds, it is important to make a precise range measurement with a Q-switched laser and a range-gated receiver.

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Maemura, Kosei, Yuko Mataki, Hiroshi Kurahara, Satoshi Iino, Masahiko Sakoda, Shinichi Ueno, Hiroyuki Shinchi, Sonshin Takao, and Shoji Natsugoe. "Clinical Impact of Intraoperative Navigation Using a Doppler Ultrasonographic Guided Vessel Tracking Technique for Pancreaticoduodenectomy." International Surgery 99, no. 6 (November 1, 2014): 770–78. http://dx.doi.org/10.9738/intsurg-d-14-00060.1.

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Abstract During pancreaticoduodenectomy (PD), early ligation of critical vessels such as the inferior pancreaticoduodenal artery (IPDA) has been reported to reduce blood loss. Color Doppler flow imaging has become the useful diagnostic methods for the delineation of the anatomy. In this study, we assessed the utility of the intraoperative Doppler ultrasonography (Dop-US) guided vessel detection and tracking technique (Dop-Navi) for identifying critical arteries in order to reduce operative bleeding. Ninety patients who received PD for periampullary or pancreatic disease were enrolled. After 14 patients were excluded because of combined resection of portal vein or other organs, the remaining were assigned to 1 of 2 groups: patients for whom Dop-Navi was used (n = 37) and those for whom Dop-Navi was not used (n = 39; controls). We compared the ability of Dop-Navi to identify critical vessels to that of preoperative multi-detector computed tomography (MD-CT), using MD-CT data, as well as compared the perioperative status and postoperative outcome between the 2 patient groups. Intraoperative Dop-US was significantly superior to MD-CT in terms of identifying number of vessels and the ability to discriminate the IPDA from the superior mesenteric artery (SMA) based on blood flow velocity. The Dop-Navi patients had shorter operation times (531 min versus 577 min; no significance) and smaller bleeding volumes (1120 mL versus 1590 mL; P < 0.01) than the control patients without increasing postoperative complications. Intraoperative Dop-Navi method allows surgeons to clearly identify the IPDA during PD and to avoid injuries to major arteries.

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Okazaki, M., H. Higashihara, H. Ono, F. Koganemaru, R. Fujimitsu, Y. Mizuma, T. Nakamura, S. Sato, S. Kimura, and S. Kodama. "Chemoembolization for Hepatocellular Carcinoma via the Inferior Pancreaticoduodenal Artery in Patients with Celiac Artery Stenosis." Acta Radiologica 34, no. 1 (January 1993): 20–25. http://dx.doi.org/10.1177/028418519303400105.

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Twenty-one patients with hepatocellular carcinoma (HCC) accompanied by extensive celiac artery stenosis or obstruction were treated by chemoembolization via the inferior pancreaticoduodenal artery (IPDA). The tip of the catheter was placed in the arteries in front of the confluence with the proper hepatic artery in 12 patients (group A: the proximal portion of the IPDA in 10, and common hepatic artery in 2), and in the proper hepatic artery or branches of it (group B) in 9 using a coaxial catheter system. Transient hyperamylasemia was observed in 10 of the 12 patients in group A and in 3 of the 9 patients in group B after chemoembolization. Splenic infarction developed in 8 patients in group A and in none in group B. Intrapancreatic fluid collection was present in 2 patients in group A following chemoembolization. No fatal complications were encountered. The 1-, 2-, and 3-year survival rates of the 10 patients in group A treated by only chemoembolization were 90, 57, and 23%, respectively (mean survival 780 days). The 1- and 2-year survival rates of 9 patients in group B were 85.8 and 85.8% (mean 879 days), respectively. Considering the severity of complications and the survival rates in groups A and B, chemoembolization by superselective catheterization into the hepatic artery via the IPDA is the treatment of choice. However, chemoembolization from the arteries in front of the confluence with the proper hepatic artery seems to be acceptable in cases of hypervascular HCC which fail to be superselectively catheterized.

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Cai, Mengyang, Ge Han, Xin Ma, Zhipeng Pei, and Wei Gong. "Active–passive collaborative approach for XCO₂ retrieval using spaceborne sensors." Optics Letters 47, no. 16 (August 12, 2022): 4211. http://dx.doi.org/10.1364/ol.464870.

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We propose a novel, to the best of our knowledge, active–passive collaborative retrieval method for measuring XCO2 (APCRM-CO2). This method simultaneously uses observations from spectrometers and integrated path differential absorption laser detection and ranging (IPDA LIDAR), thus making its products have both the coverage advantages of passive detection and the high information content of active detection. The results of simulation experiments show that APCRM-CO2 can reduce the retrieval error by 15% to 70%. The minimum SNR for achieving 1 ppm is 24.7 dB. All these results are obtained without considering the LIDAR measured aerosol profile as input. Therefore, greater performance improvements on XCO2 retrievals are expected in the future for real data processing. The first satellite mission, DQ-2, carrying both a spectrometer and an IPDA LIDAR is planned to be launched by 2025. With the help of APCRM-CO2, its XCO2 products would better assist us with understanding the carbon cycle.

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Akbari, Behzad, Jeyan Thiyagalingam, Richard Lee, and Kirubarajan Thia. "A Multilane Tracking Algorithm Using IPDA with Intensity Feature." Sensors 21, no. 2 (January 11, 2021): 461. http://dx.doi.org/10.3390/s21020461.

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Detection of multiple lane markings on road surfaces is an important aspect of autonomous vehicles. Although a number of approaches have been proposed to detect lanes, detecting multiple lane markings, particularly across a large number of frames and under varying lighting conditions, in a consistent manner is still a challenging problem. In this paper, we propose a novel approach for detecting multiple lanes across a large number of frames and under various lighting conditions. Instead of resorting to the conventional approach of processing each frame to detect lanes, we treat the overall problem as a multitarget tracking problem across space and time using the integrated probabilistic data association filter (IPDAF) as our basis filter. We use the intensity of the pixels as an augmented feature to correctly group multiple lane markings using the Hough transform. By representing these extracted lane markings as splines, we then identify a set of control points, which becomes a set of targets to be tracked over a period of time, and thus across a large number of frames. We evaluate our approach on two different fronts, covering both model- and machine-learning-based approaches, using two different datasets, namely the Caltech and TuSimple lane detection datasets, respectively. When tested against model-based approach, the proposed approach can offer as much as 5%, 12%, and 3% improvements on the true positive, false positive, and false positives per frame rates compared to the best alternative approach, respectively. When compared against a state-of-the-art machine learning technique, particularly against a supervised learning method, the proposed approach offers 57%, 31%, 4%, and 9× improvements on the false positive, false negative, accuracy, and frame rates. Furthemore, the proposed approach retains the explainability, or in other words, the cause of actions of the proposed approach can easily be understood or explained.

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Akbari, Behzad, Jeyan Thiyagalingam, Richard Lee, and Thia Kirubarajan. "A Multilane Tracking Algorithm Using IPDA with Intensity Feature." Sensors 21, no. 2 (January 11, 2021): 461. http://dx.doi.org/10.3390/s21020461.

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Detection of multiple lane markings on road surfaces is an important aspect of autonomous vehicles. Although a number of approaches have been proposed to detect lanes, detecting multiple lane markings, particularly across a large number of frames and under varying lighting conditions, in a consistent manner is still a challenging problem. In this paper, we propose a novel approach for detecting multiple lanes across a large number of frames and under various lighting conditions. Instead of resorting to the conventional approach of processing each frame to detect lanes, we treat the overall problem as a multitarget tracking problem across space and time using the integrated probabilistic data association filter (IPDAF) as our basis filter. We use the intensity of the pixels as an augmented feature to correctly group multiple lane markings using the Hough transform. By representing these extracted lane markings as splines, we then identify a set of control points, which becomes a set of targets to be tracked over a period of time, and thus across a large number of frames. We evaluate our approach on two different fronts, covering both model- and machine-learning-based approaches, using two different datasets, namely the Caltech and TuSimple lane detection datasets, respectively. When tested against model-based approach, the proposed approach can offer as much as 5%, 12%, and 3% improvements on the true positive, false positive, and false positives per frame rates compared to the best alternative approach, respectively. When compared against a state-of-the-art machine learning technique, particularly against a supervised learning method, the proposed approach offers 57%, 31%, 4%, and 9× improvements on the false positive, false negative, accuracy, and frame rates. Furthemore, the proposed approach retains the explainability, or in other words, the cause of actions of the proposed approach can easily be understood or explained.

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Tellier, Yoann, Clémence Pierangelo, Martin Wirth, and Fabien Gibert. "Averaging Bias Correction for Future IPDA Lidar Mission MERLIN." EPJ Web of Conferences 176 (2018): 02020. http://dx.doi.org/10.1051/epjconf/201817602020.

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The CNES/DLR MERLIN satellite mission aims at measuring methane dry-air mixing ratio column (XCH4) and thus improving surface flux estimates. In order to get a 1% precision on XCH4 measurements, MERLIN signal processing assumes an averaging of data over 50 km. The induced biases due to the non-linear IPDA lidar equation are not compliant with accuracy requirements. This paper analyzes averaging biases issues and suggests correction algorithms tested on realistic simulated scenes.

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Ma, Xin, Haowei Zhang, Ge Han, Hao Xu, Tianqi Shi, Wei Gong, Yue Ma, and Song Li. "High-Precision CO2 Column Length Analysis on the Basis of a 1.57-μm Dual-Wavelength IPDA Lidar." Sensors 20, no. 20 (October 17, 2020): 5887. http://dx.doi.org/10.3390/s20205887.

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For high-precision measurements of the CO2 column concentration in the atmosphere with airborne integrated path differential absorption (IPDA) Lidar, the exact distance of the Lidar beam to the scattering surface, that is, the length of the column, must be measured accurately. For the high-precision inversion of the column length, we propose a set of methods on the basis of the actual conditions, including autocorrelation detection, adaptive filtering, Gaussian decomposition, and optimized Levenberg–Marquardt fitting based on the generalized Gaussian distribution. Then, based on the information of a pair of laser pulses, we use the direct adjustment method of unequal precision to eliminate the error in the distance measurement. Further, the effect of atmospheric delay on distance measurements is considered, leading to further correction of the inversion results. At last, an airborne experiment was carried out in a sea area near Qinhuangdao, China on 14 March 2019. The results showed that the ranging accuracy can reach 0.9066 m, which achieved an excellent ranging accuracy on 1.57-μm IPDA Lidar and met the requirement for high-precision CO2 column length inversion.

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Radosavljevic, Zvonko. "IPDA filters in the sense of Gaussian mixture PHD algorithm." Scientific Technical Review 66, no. 3 (2016): 34–39. http://dx.doi.org/10.5937/str1603034r.

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Wang, Xuezhi, and Darko Musicki. "Low elevation sea-surface target tracking using IPDA type filters." IEEE Transactions on Aerospace and Electronic Systems 43, no. 2 (April 2007): 759–74. http://dx.doi.org/10.1109/taes.2007.4285369.

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Huang, Yuan, Yifang Shi, and Taek Song. "An Efficient Multi-Path Multitarget Tracking Algorithm for Over-The-Horizon Radar." Sensors 19, no. 6 (March 20, 2019): 1384. http://dx.doi.org/10.3390/s19061384.

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In target tracking environments using over-the-horizon radar (OTHR), one target may generate multiple detections through different signal propagation paths. Trackers need to jointly handle the uncertainties stemming from both measurement origin and measurement path. Traditional multitarget tracking algorithms suffer from high computational loads in such environments since they need to enumerate all possible joint measurement-to-track assignments considering the measurements paths unless they employ some approximations regarding the measurements and their corresponding paths. In this paper, we propose a novel algorithm, named multi-path linear multitarget integrated probabilistic data association (MP-LM-IPDA), to efficiently track multitarget in multiple detection environments. Instead of generating all possible joint assignments, MP-LM-IPDA calculates the modulated clutter measurement density for each measurement cell of each track. The modulated clutter measurement density considers the possibility that the measurement cells originate from the clutter as well as from other potential targets. By incorporating the modulated clutter measurement density, the single target tracking structure can be applied for multitarget tracking, which significantly reduces the computational load. The simulation results demonstrate the effectiveness and efficiency of the proposed algorithm.

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Menzies, Robert T., Gary D. Spiers, and Joseph Jacob. "Airborne Laser Absorption Spectrometer Measurements of Atmospheric CO2 Column Mole Fractions: Source and Sink Detection and Environmental Impacts on Retrievals." Journal of Atmospheric and Oceanic Technology 31, no. 2 (February 1, 2014): 404–21. http://dx.doi.org/10.1175/jtech-d-13-00128.1.

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Abstract This paper provides atmospheric CO2 column abundance measurement results from a summer 2011 series of flights of a 2.05-μm laser absorption spectrometer on the NASA DC-8 research aircraft. The integrated path differential absorption (IPDA) method is used for the CO2 column mole fraction retrievals. This instrument and the data analysis methodology developed to achieve retrievals over complex terrain and variable atmospheric conditions provide insight into the capabilities of the IPDA method for both airborne measurements and future global-scale CO2 measurements from low-Earth orbit pertinent to the proposed NASA Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission. Demonstrated in this paper is the capability to measure CO2 drawdown caused by crop activity during a midday flight over the U.S. upper Midwest area. In addition, an example is provided of high spatial resolution measurements of CO2 plumes from individual stack clusters of the Four Corners Power Plant in northwestern New Mexico. Complex terrain, the spectral properties of the aboveground scatterers, and potential cloud contamination are factors that complicate the column abundance retrieval. The impacts of these factors and various means of minimizing these influences in the retrievals are discussed.

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Ishii, S., M. Koyama, P. Baron, H. Iwai, K. Mizutani, T. Itabe, A. Sato, and K. Asai. "Ground-based integrated path coherent differential absorption lidar measurement of CO<sub>2</sub>: hard target return." Atmospheric Measurement Techniques Discussions 5, no. 6 (November 29, 2012): 8579–607. http://dx.doi.org/10.5194/amtd-5-8579-2012.

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Abstract. The National Institute of Information and Communications Technology (NICT) have made a great deal of effort to develop a coherent 2-μm differential absorption and wind lidar (Co2DiaWiL) for measuring CO2 and wind speed. First, coherent Integrated Path Differential Absorption (IPDA) lidar experiments were conducted using the Co2DiaWiL and a hard target (surface return) located about 7.12 km south of NICT on 11, 27, and 28 December 2010. The detection sensitivity of a 2-μm IPDA lidar was examined in detail using the CO2 concentration measured by the hard target. The precisions of CO2 measurement for the hard target and 900, 4500 and 27 000 shot pairs were 6.5, 2.8, and 1.2%, respectively. The results indicated that a coherent IPDA lidar with a laser operating at a high pulse repetition frequency of a few tens of KHz is necessary for measuring the CO2 concentration of the hard target with a precision of 1–2 ppm. Statistical comparisons indicated that, although a small amount of in situ data and the fact that they were not co-located with the hard target made comparison difficult, the CO2 volume mixing ratio measured with the Co2DiaWiL was about 5 ppm lower than that measured with the in situ sensor. The statistical results indicated that there were no differences between the hard target and atmospheric return measurements. A precision of 1.5% was achieved from the atmospheric return, which is lower than that obtained from the hard-target returns. Although long-range DIfferential Absorption Lidar (DIAL) CO2 measurement with the atmospheric return can result in highly precise measurement, the precision of the atmospheric return measurement was widely distributed comparing to that of the hard target return. Our results indicated that it is important to use a Q-switched laser to measure the range-gated differential absorption optical depth with the atmospheric return and that it is better to simultaneously conduct both hard target and atmospheric return measurements to enable highly accurate CO2 measurement.

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Cao, Xifeng, Lu Zhang, Xingying Zhang, Sen Yang, Zhili Deng, Xin Zhang, and Yuhan Jiang. "Study on the Impact of the Doppler Shift for CO2 Lidar Remote Sensing." Remote Sensing 14, no. 18 (September 16, 2022): 4620. http://dx.doi.org/10.3390/rs14184620.

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Atmospheric carbon dioxide (CO2) is recognized as the most important component of the greenhouse gases, the concentration of which has increased rapidly since the pre-industrial era due to anthropogenic emissions of greenhouse gases (GHG). The accurate monitoring of carbon dioxide is essential to study the global carbon cycle and radiation budget on Earth. The Aerosol and Carbon Detection Lidar (ACDL) instrument onboard the Atmospheric Environmental Monitoring Satellite (AEMS) was successfully launched in April 2022, which allows a new perspective to quantify the global spatial distribution of atmospheric CO2 with high accuracy. In this work, the impact of the Doppler shift on CO2 measurements for an integrated-path differential absorption (IPDA) light detection and ranging (lidar) system was evaluated to meet the weighted column-averaged mixing ratio of carbon dioxide (XCO2) measurement requirements of less than one part per million (ppm). The measurement uncertainties due to the Doppler shift were first evaluated in airborne IPDA observations. The result shows that most of the Doppler shift is in the range of 6–8 MHz, resulting in 0.26-0.39 ppm deviations in the XCO2 results. The deviations between the XCO2 retrievals and in situ measurements decreased to 0.16 ppm after the correction of the Doppler shift from 11:28:29 to 11:28:49 in the flight campaign. In addition, the online Doppler shift accounts for 98% of the deviations between XCO2 retrievals and in situ measurements. Furthermore, the impact of the Doppler shift on ACDL measurements is also assessed. The differences between the XCO2 retrievals with and without Doppler shift are used to quantify measurement uncertainties due to the Doppler effect. The simulations reveal that a pointing misalignment of 0.067 mrad can lead to a mean bias of about 0.30 ppm (0.072%) in the CO2 column. In addition, CO2 measurements are more sensitive to the Doppler shift at high altitudes for IPDA lidar, so the largest differences in the CO2 columns are found on the Qinghai–Tibet Plateau in China.

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Chowdhury, Subhadeep. "MEDICINE AND COLONIAL PATENT LAW IN INDIA: A Study of Patent Medicines and the Indian Patents and Designs Act, 1911 in Early- Twentieth-Century India." Journal of the History of Medicine and Allied Sciences 75, no. 4 (October 1, 2020): 408–28. http://dx.doi.org/10.1093/jhmas/jraa027.

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ABSTRACT This paper investigates the history of drugs sold as “patent medicines” in India in the early twentieth century. The paper investigates their legitimacy as patenting of medicines was forbidden by the Indian Patents and Designs Act, 1911 (IPDA). The paper argues that the instrument of letters patents functioning as the prerogative of the Crown that gave monopolistic rights to grantees to sell any compound without having to disclose its constituents was the reason behind this seemingly conflicting historical relationship between the law and the market. Colonial law-making left sufficient space within the ambit of the IPDA for letters patents to have their ill effects. The colonial state made attempts to address this as a public health issue by incorporating concerns related to this class of medicines within regulations addressed to the drugs market in the 1930s. The currency of patent medicines in the market was further added to by Indian indigenous entrepreneurs fueled by cultural nationalism of Swadeshi ideology in Bengal in the early twentieth century. However, even such indigenous responses or attempts at hybridization of manufacturing and selling practices related to patent medicines were mostly informed by upper-caste/ upper-class interests and not so much by those of consumers of these medicines.

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Tarvainen, Kylliki, Riitta Jolanki, Maj-Len Henriks Eckerman, and Tuula Estlander. "Occupational allergic contact dermatitis from isophoronediamine (IPDA) in operative-clothing manufacture." Contact Dermatitis 39, no. 1 (July 1998): 46–47. http://dx.doi.org/10.1111/j.1600-0536.1998.tb05826.x.

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Du, Juan, Jiqiao Liu, Decang Bi, Xiuhua Ma, Xia Hou, Xiaolei Zhu, and Weibiao Chen. "Validation of double-pulse 1572 nm integrated path differential absorption lidar measurement of carbon dioxide." EPJ Web of Conferences 176 (2018): 01031. http://dx.doi.org/10.1051/epjconf/201817601031.

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A ground-based double-pulse 1572 nm integrated path differential absorption (IPDA) lidar was developed for carbon dioxide (CO2) column concentrations measurement. The lidar measured the CO2 concentrations continuously by receiving the scattered echo signal from a building about 1300 m away. The other two instruments of TDLAS and in-situ CO2 analyzer measured the CO2 concentrations on the same time. A CO2 concentration measurement of 430 ppm with 1.637 ppm standard error was achieved.

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Olivier, Chomette, Raymond Armante, Cyril Crevoisier, Thibault Delahaye, Dimitri Edouart, Fabien Gibert, Frédéric Nahan, and Yoann Tellier. "CH4 IPDA Lidar mission data simulator and processor for MERLIN: prototype development at LMD/CNRS/Ecole Polytechnique." EPJ Web of Conferences 176 (2018): 02016. http://dx.doi.org/10.1051/epjconf/201817602016.

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The MEthane Remote sensing Lidar missioN (MERLIN), currently in phase C, is a joint cooperation between France and Germany on the development of a spatial Integrated Path Differential Absorption (IPDA) LIDAR (LIght Detecting And Ranging) to conduct global observations of atmospheric methane. This presentation will focus on the status of a LIDAR mission data simulator and processor developed at LMD (Laboratoire de Météorologie Dynamique), Ecole Polytechnique, France, for MERLIN to assess the performances in realistic observational situations.

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45

Eloi, Márcia Emília da Rocha Assis, Juliana Nunes Santos, and Vanessa Oliveira Martins-Reis. "Programa fonoaudiológico de formação de professores: avaliação da efetividade." Distúrbios da Comunicação 29, no. 4 (December 27, 2017): 759. http://dx.doi.org/10.23925/2176-2724.2017v29i4p759-771.

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Objetivo: testar a efetividade do Programa Fonoaudiológico de Formação de Professores. Métodos: trata-se de um ensaio prospectivo que contou com a participação de 70 professores do ensino fundamental. O programa consta de 10 módulos e tem o objetivo de instrumentalizar os professores quanto ao desenvolvimento da linguagem oral e escrita. Os módulos tiveram duração de 2 horas cada um, que somados a 10 horas de atividades complementares, totalizou 30 horas. Para verificar a efetividade do programa, os professores responderam ao questionário “Percepção de Professores em Linguagem” que possui 10 questões de casos hipotéticos envolvendo alunos do ensino fundamental, antes e após a participação no mesmo. A partir do questionário foram criados os índices de percepção global (IPG), de alterações da linguagem oral (IPLO) e da linguagem escrita (IPLE) e do desenvolvimento adequado (IPDA). Os dados foram submetidos à análise estatística descritiva e inferencial. Resultados: Observou-se diferença estatisticamente significante pré e pós-formação nos índices IPLO, IPLE e IPG. Os professores não apresentaram diferenças no índice IPDA. Conclusão: A percepção do professor sobre os aspectos de desenvolvimento da linguagem oral e escrita mudou de forma significativa pós-participação no programa. O estudo mostra a relevância do programa de formação para os professores do ensino fundamental com efetividade na mudança da percepção frente a casos de alterações da linguagem oral e escrita.

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Singh, Upendra N., Tamer F. Refaat, Syed Ismail, Mulugeta Petros, Kenneth J. Davis, Stephan R. Kawa, and Robert T. Menzies. "Space-based active optical remote sensing of carbon dioxide column using high-energy two-micron pulsed ipda lidar." EPJ Web of Conferences 176 (2018): 02001. http://dx.doi.org/10.1051/epjconf/201817602001.

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Modeling of a space-based high-energy 2-μm triple-pulse Integrated Path Differential Absorption (IPDA) lidar was conducted to demonstrate carbon dioxide (CO2) measurement capability and to evaluate random and systematic errors. A high pulse energy laser and an advanced MCT e-APD detector were incorporated in this model. Projected performance shows 0.5 ppm precision and 0.3 ppm bias in low-tropospheric column CO2 mixing ratio measurements from space for 10 second signal averaging over Railroad Valley (RRV) reference surface.

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Antonietti, Alessandro, Roberta Finazzi, Mara Sperlari, and Lina Stefanini. "L'individuazione precoce delle difficolta scolastiche: variabilita delle indicazioni ricavate dalla scala ipda." RICERCHE DI PSICOLOGIA, no. 1 (June 2015): 47–60. http://dx.doi.org/10.3280/rip2015-001002.

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Yu, Jirong, Mulugeta Petros, Tamer Refaat, Karl Reithmaier, Ruben Remus, Upendra Singh, Will Johnson, et al. "Airborne 2-Micron Double Pulsed Direct Detection IPDA Lidar for Atmospheric CO2Measurement." EPJ Web of Conferences 119 (2016): 03004. http://dx.doi.org/10.1051/epjconf/201611903004.

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Tellier, Yoann, Clémence Pierangelo, Martin Wirth, Fabien Gibert, and Fabien Marnas. "Averaging bias correction for the future space-borne methane IPDA lidar mission MERLIN." Atmospheric Measurement Techniques 11, no. 10 (October 24, 2018): 5865–84. http://dx.doi.org/10.5194/amt-11-5865-2018.

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Abstract. The CNES (French Space Agency) and DLR (German Space Agency) project MERLIN is a future integrated path differential absorption (IPDA) lidar satellite mission that aims at measuring methane dry-air mixing ratio columns (XCH4) in order to improve surface flux estimates of this key greenhouse gas. To reach a 1 % relative random error on XCH4 measurements, MERLIN signal processing performs an averaging of data over 50 km along the satellite trajectory. This article discusses how to process this horizontal averaging in order to avoid the bias caused by the non-linearity of the measurement equation and measurements affected by random noise and horizontal geophysical variability. Three averaging schemes are presented: averaging of columns of XCH4, averaging of columns of differential absorption optical depth (DAOD) and averaging of signals. The three schemes are affected both by statistical and geophysical biases that are discussed and compared, and correction algorithms are developed for the three schemes. These algorithms are tested and their biases are compared on modelled scenes from real satellite data. To achieve the accuracy requirements that are limited to 0.2 % relative systematic error (for a reference value of 1780 ppb), we recommend performing the averaging of signals corrected from the statistical bias due to the measurement noise and from the geophysical bias mainly due to variations of methane optical depth and surface reflectivity along the averaging track. The proposed method is compliant with the mission relative systematic error requirements dedicated to averaging algorithms of 0.06 % (±1 ppb for XCH4=1780ppb) for all tested scenes and all tested ground reflectivity values.

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Fix, Andreas, Axel Amediek, Christian Büdenbender, Gerhard Ehret, Christoph Kiemle, Mathieu Quatrevalet, Martin Wirth, et al. "CH4 and CO2 IPDA Lidar Measurements During the Comet 2018 Airborne Field Campaign." EPJ Web of Conferences 237 (2020): 03005. http://dx.doi.org/10.1051/epjconf/202023703005.

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Installed onboard the German research aircraft HALO, the integrated-path differential-absorption (IPDA) lidar CHARM-F measures weighted vertical columns of both greenhouse gases (GHG) below the aircraft and along its flight track, aiming at high accuracy and precision. Results will be shown from the deployment during the CoMet field campaign that was carried out in spring 2018, with its main focus on one of the major European hot spots in methane emissions: the Upper Silesian Coal Basin (USCB) in Poland. First analyses reveal a measurement precision of below 0.5% for 20-km averages and also low bias, which was assessed by comparison with in-situ instruments. The measurements flights were designed to capture individual CH4 and CO2 plumes from e.g. coal mine venting and coal-fired power plants, respectively, but also to measure large and regional scale GHG gradients and to provide comparisons with the Total Carbon Column Observing Network (TCCON). Many other different instruments, both airborne and ground-based, complemented the lidar measurements to provide a comprehensive dataset for model analyses. CHARM-F also acts as the airborne demonstrator for MERLIN, the “Methane Remote Lidar Mission”, conducted by the German and French space agencies, DLR and CNES, with launch foreseen in ~ 2024. In this context, the airborne lidar data are likewise important for mission support such as for e.g. algorithm development and improvement and, moreover, the CoMet mission was also an important step for MERLIN validation preparation.

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