scholarly journals BIDIRECTIONAL REFLECTANCE DISTRIBUTION FUNCTION (BRDF) OF MIXED PIXELS

2021 ◽  
Vol XLIII-B3-2021 ◽  
pp. 195-200
Author(s):  
F. Kizel ◽  
Y. Vidro
Keyword(s):  
Mutual Influence ◽  
Laboratory Data ◽  
Spectral Unmixing ◽  
Spectral Signature ◽  
Empirical Correction ◽  
Reflected Light ◽  
Wide Range ◽  
Mixed Pixels ◽  
Semi Empirical ◽  
Spectral Mixture

Abstract. Hyperspectral imaging is crucial for a variety of land-cover mapping and analyzing tasks. The available large number of reflected light measurements along a wide range of wavelengths allows for distinguishing between different materials under various conditions. Though, several effects bear an undesired variability within hyperspectral images and increase the complexity of interpreting such data. Two of the most significant effects in this regard are the BRDF and the spectral mixture. Due to the first, the acquisitions geometrical and viewing conditions influences the measured spectral signature of a surface to a large extent. On the other hand, because of the typical low spatial resolution of remotely sensed images, each pixel can contain more than one material. Despite much research addressing either the BRDF effect and ways to correct it or the spectral unmixing, too few works considered these two effects' mutual influence. In this work, we study the BRDF of mixed pixels and present preliminary insights of testing a strategy to correct its undesired impact on the data by incorporating the EMs fractions within an unmixing-based semi-empirical correction model. Experimental results using real laboratory data acquired under controlled conditions clearly show the significant improvement of the corrected reflectance results through the proposed model.

Generational Spillover in the Resistance to Trump

2018 ◽  
Author(s):  
Nancy Whittier
Keyword(s):  
Generation X ◽  
Mutual Influence ◽  
Organizational Structures ◽  
Wide Range ◽  
Political Generations ◽  
1960S And 1970S ◽  
The 1960S

The anti-Trump Resistance involves activists from an unusually wide range of political and chronological generations: movement veterans from the 1960s and 1970s, Generation X activists politicized in the 1980s and 1990s, Millennials who entered activism in the 2000s, and newcomers of all ages. Political generations differ in worldview based on both age and time of entry into activism. Generational spillover—the mutual influence, difference, and conflict among political generations—includes explicit attempts to teach organizing, and indirect influences on frames, organizational structures, tactics, ideologies, and goals. This chapter discusses generational spillover in the Resistance, including transmission and conflict.

Krypton 85 myocardial blood flow: precordial scintillation versus coronary sinus sampling

1965 ◽  
Vol 209 (4) ◽  
pp. 705-710 ◽  
Author(s):  
Michael D. Klein ◽  
Lawrence S. Cohen ◽  
Richard Gorlin
Keyword(s):  
Blood Flow ◽  
Myocardial Blood Flow ◽  
Coronary Sinus ◽  
Human Subjects ◽  
Radioactive Decay ◽  
Empirical Correction ◽  
Wide Range ◽  
Actual Flow ◽  
Flow Through ◽  
High Degree

Myocardial blood flow in human subjects was assessed by comparative simultaneous measurement of krypton 85 radioactive decay from coronary sinus and precordial scintillation. Empirical correction of postclearance background from precordial curves yielded a high degree of correlation between flows derived from the two sampling sites (r = .889, P < .001). Comparison of left and right coronary flows in nine subjects revealed similarity in flow through the two vessels over a wide range of actual flow values (r = .945, P < .001).

scholarly journals DFT calculation and assignment of vibrational spectra of aryl and alkyl chlorophosphates

2014 ◽  
Vol 12 (2) ◽  
pp. 153-163
Author(s):  
Viktor Anishchenko ◽  
Vladimir Rybachenko ◽  
Konstantin Chotiy ◽  
Andrey Redko
Keyword(s):  
Vibrational Spectra ◽  
Basis Sets ◽  
Heavy Atoms ◽  
Wide Range ◽  
Complete Assignment ◽  
Key Factor ◽  
Polarization Functions ◽  
Experimental Values ◽  
Semi Empirical ◽  
Good Agreement

AbstractDFT calculations of vibrational spectra of chlorophosphates using wide range of basis sets and hybrid functionals were performed. Good agreement between calculated and experimental vibrational spectra was reached by the combination of non-empirical functional PBE0 with both middle and large basis sets. The frequencies of the stretching vibrations of the phosphate group calculated using semi-empirical functional B3LYP for all basis sets deviate significantly from the experimental values. The number of polarization functions on heavy atoms was shown to be a key factor for the calculation of vibrational frequencies of organophosphates. The importance of consideration of all the stable rotamers for a complete assignment of fundamental modes was shown.

scholarly journals Remote Sensing of Sea Surface Artificial Floating Plastic Targets with Sentinel-2 and Unmanned Aerial Systems (Plastic Litter Project 2019)

2020 ◽  
Vol 12 (12) ◽  
pp. 2013
Author(s):  
Konstantinos Topouzelis ◽  
Dimitris Papageorgiou ◽  
Alexandros Karagaitanakis ◽  
Apostolos Papakonstantinou ◽  
Manuel Arias Ballesteros
Keyword(s):  
Remote Sensing ◽  
Large Scale ◽  
Field Experiments ◽  
Spectral Unmixing ◽  
Sea Surface ◽  
Spectral Signature ◽  
Unmanned Aerial Systems ◽  
Real Environment ◽  
Promising Tool ◽  
Sentinel 2

Remote sensing is a promising tool for the detection of floating marine plastics offering extensive area coverage and frequent observations. While floating plastics are reported in high concentrations in many places around the globe, no referencing dataset exists either for understanding the spectral behavior of floating plastics in a real environment, or for calibrating remote sensing algorithms and validating their results. To tackle this problem, we initiated the Plastic Litter Projects (PLPs), where large artificial plastic targets were constructed and deployed on the sea surface. The first such experiment was realised in the summer of 2018 (PLP2018) with three large targets of 10 × 10 m. Hereafter, we present the second Plastic Litter Project (PLP2019), where smaller 5 × 5 m targets were constructed to better simulate near-real conditions and examine the limitations of the detection with Sentinel-2 images. The smaller targets and the multiple acquisition dates allowed for several observations, with the targets being connected in a modular way to create different configurations of various sizes, material composition and coverage. A spectral signature for the PET (polyethylene terephthalate) targets was produced through modifying the U.S. Geological Survey PET signature using an inverse spectral unmixing calculation, and the resulting signature was used to perform a matched filtering processing on the Sentinel-2 images. The results provide evidence that under suitable conditions, pixels with a PET abundance fraction of at least as low as 25% can be successfully detected, while pinpointing several factors that significantly impact the detection capabilities. To the best of our knowledge, the 2018 and 2019 Plastic Litter Projects are to date the only large-scale field experiments on the remote detection of floating marine litter in a near-real environment and can be used as a reference for more extensive validation/calibration campaigns.

scholarly journals Modeling the processes of aerogasdynamics of structural elements of a supersonic aircraft

2019 ◽  
Author(s):  
E.S. Studennikov
Keyword(s):  
Stress Transfer ◽  
Aerodynamic Characteristics ◽  
Wind Tunnels ◽  
Transfer Model ◽  
Structural Elements ◽  
Base Region ◽  
Supersonic Aircraft ◽  
Wide Range ◽  
Sharp Cone ◽  
Semi Empirical

The purpose of the research was to study the aerodynamic features of the flow around the simplest structural elements of an aircraft, such as sharp and blunt-nose cones. For calculations we applied the perfect gas model. To describe flows with large adverse pressure gradients, we used the Menter's shear stress transfer model. We analyzed changes in the aerodynamic characteristics of the cones in a wide range of angles of attack α and flow Mach M∞ numbers. Furthermore, we investigated the parameters of the base region of the sharp cone at transonic and supersonic speeds, and compared the simulation results with the data of a physical experiment both in wind tunnels and on a ballistic installation. The comparison showed good agreement with the experimental data. Numerical simulation data can be applied to form the external appearance of aircraft for various purposes, to study the influence of the temperature factor on the flow around bodies, and to create semi-empirical models for calculating the parameters of the base region of conical bodies.

scholarly journals Nonbacterial Thrombotic Endocarditis Associated with Acute Promyelocytic Leukemia: An Autopsy Case Report

Medicina ◽  
2021 ◽  
Vol 57 (11) ◽  
pp. 1264
Author(s):  
Tadayuki Hashimoto ◽  
Tatsuya Aoki ◽  
Yoshitaka Kawabata ◽  
Yoshihiro Owai ◽  
Yoshikazu Matsuda ◽  
...  
Keyword(s):  
Acute Promyelocytic Leukemia ◽  
Laboratory Data ◽  
Anticoagulation Therapy ◽  
Sudden Onset ◽  
Promyelocytic Leukemia ◽  
Intensity Change ◽  
High Signal ◽  
Left Brain ◽  
Wide Range ◽  
Nonbacterial Thrombotic Endocarditis

Valve vegetation is one of the most fearful findings for physicians. The first diagnosis that comes to their mind is infective endocarditis (IE), but it can also be noninfective; nonbacterial thrombotic endocarditis (NBTE). NBTE can be even more challenging than IE for physicians because of the wide range of differential diagnoses such as malignancies, autoimmune disorders and human immunodeficiency virus. A 45-year-old woman presented at the emergency room with a sudden onset of dysarthria and right-sided hemiplegia. Laboratory data showed her blood counts and coagulation test were mostly normal and the magnetic resonance imaging detected a high-signal-intensity change in her left brain. An echocardiogram found a vegetation-like structure on her atrial valve. We highly suspected IE leading to cerebral embolism. The clot was successfully removed by our neurosurgeons and anticoagulation therapy was started concurrently. Her state of consciousness improved, but then she suffered a brain hemorrhage and died. The autopsy revealed that the cause of her vegetation was acute promyelocytic leukemia (APL). Based on these findings, it is important to remember that APL can be the cause of NBTE even if the blood count and coagulation tests are almost normal.

scholarly journals A national study of practice patterns in UK renal units in the use of dialysis and conservative kidney management to treat people aged 75 years and over with chronic kidney failure

2015 ◽  
Vol 3 (12) ◽  
pp. 1-186 ◽  
Author(s):  
Paul Roderick ◽  
Hugh Rayner ◽  
Sarah Tonkin-Crine ◽  
Ikumi Okamoto ◽  
Caroline Eyles ◽  
...  
Keyword(s):  
Kidney Failure ◽  
Older Patients ◽  
Practice Patterns ◽  
Laboratory Data ◽  
National Study ◽  
Service Development ◽  
Renal Unit ◽  
Number Of Patients ◽  
Wide Range ◽  
The Way

BackgroundConservative kidney management (CKM) is recognised as an alternative to dialysis for a significant number of older adults with multimorbid stage 5 chronic kidney disease (CKD5). However, little is known about the way CKM is delivered or how it is perceived.AimTo determine the practice patterns for the CKM of older patients with CKD5, to inform service development and future research.Objectives(1) To describe the differences between renal units in the extent and nature of CKM, (2) to explore how decisions are made about treatment options for older patients with CKD5, (3) to explore clinicians’ willingness to randomise patients with CKD5 to CKM versus dialysis, (4) to describe the interface between renal units and primary care in managing CKD5 and (5) to identify the resources involved and potential costs of CKM.MethodsMixed-methods study. Interviews with 42 patients aged > 75 years with CKD5 and 60 renal unit staff in a purposive sample of nine UK renal units. Interviews informed the design of a survey to assess CKM practice, sent to all 71 UK units. Nineteen general practitioners (GPs) were interviewed concerning the referral of CKD patients to secondary care. We sought laboratory data on new CKD5 patients aged > 75 years to link with the nine renal units’ records to assess referral patterns.ResultsSixty-seven of 71 renal units completed the survey. Although terminology varied, there was general acceptance of the role of CKM. Only 52% of units were able to quantify the number of CKM patients. A wide range reflected varied interpretation of the designation ‘CKM’ by both staff and patients. It is used to characterise a future treatment option as well as non-dialysis care for end-stage kidney failure (i.e. a disease state equivalent to being on dialysis). The number of patients in the latter group on CKM was relatively small (median 8, interquartile range 4.5–22). Patients’ expectations of CKM and dialysis were strongly influenced by renal staff. In a minority of units, CKM was not discussed. When discussed, often only limited information about illness progression was provided. Staff wanted more research into the relative benefits of CKM versus dialysis. There was almost universal support for an observational methodology and a quarter would definitely be willing to participate in a randomised clinical trial, indicating that clinicians placed value on high-quality evidence to inform decision-making. Linked data indicated that most CKD5 patients were known to renal units. GPs expressed a need for guidance on when to refer older multimorbid patients with CKD5 to nephrology care. There was large variation in the scale and model of CKM delivery. In most, the CKM service was integrated within the service for all non-renal replacement therapy CKD5 patients. A few units provided dedicated CKM clinics and some had dedicated, modest funding for CKM.ConclusionsConservative kidney management is accepted across UK renal units but there is much variation in the way it is described and delivered. For best practice, and for CKM to be developed and systematised across all renal units in the UK, we recommend (1) a standard definition and terminology for CKM, (2) research to measure the relative benefits of CKM and dialysis and (3) development of evidence-based staff training and patient education interventions.FundingThe National Institute for Health Research Health Services and Delivery Research programme.

scholarly journals Enabling Agile Clinical and Translational Data Warehousing: Platform Development and Evaluation (Preprint)

2019 ◽  
Author(s):  
Helmut Spengler ◽  
Claudia Lang ◽  
Tanmaya Mahapatra ◽  
Ingrid Gatz ◽  
Klaus A Kuhn ◽  
...  
Keyword(s):  
Laboratory Data ◽  
Data Representation ◽  
Heterogeneous Data ◽  
Use Cases ◽  
Iterative Refinement ◽  
Cloud Infrastructure ◽  
Specific Domain ◽  
Wide Range ◽  
Data Loading ◽  
Time Required

BACKGROUND Modern data-driven medical research provides new insights into the development and course of diseases and enables novel methods of clinical decision support. Clinical and translational data warehouses, such as Informatics for Integrating Biology and the Bedside (i2b2) and tranSMART, are important infrastructure components that provide users with unified access to the large heterogeneous data sets needed to realize this and support use cases such as cohort selection, hypothesis generation, and ad hoc data analysis. OBJECTIVE Often, different warehousing platforms are needed to support different use cases and different types of data. Moreover, to achieve an optimal data representation within the target systems, specific domain knowledge is needed when designing data-loading processes. Consequently, informaticians need to work closely with clinicians and researchers in short iterations. This is a challenging task as installing and maintaining warehousing platforms can be complex and time consuming. Furthermore, data loading typically requires significant effort in terms of data preprocessing, cleansing, and restructuring. The platform described in this study aims to address these challenges. METHODS We formulated system requirements to achieve agility in terms of platform management and data loading. The derived system architecture includes a cloud infrastructure with unified management interfaces for multiple warehouse platforms and a data-loading pipeline with a declarative configuration paradigm and meta-loading approach. The latter compiles data and configuration files into forms required by existing loading tools, thereby automating a wide range of data restructuring and cleansing tasks. We demonstrated the fulfillment of the requirements and the originality of our approach by an experimental evaluation and a comparison with previous work. RESULTS The platform supports both i2b2 and tranSMART with built-in security. Our experiments showed that the loading pipeline accepts input data that cannot be loaded with existing tools without preprocessing. Moreover, it lowered efforts significantly, reducing the size of configuration files required by factors of up to 22 for tranSMART and 1135 for i2b2. The time required to perform the compilation process was roughly equivalent to the time required for actual data loading. Comparison with other tools showed that our solution was the only tool fulfilling all requirements. CONCLUSIONS Our platform significantly reduces the efforts required for managing clinical and translational warehouses and for loading data in various formats and structures, such as complex entity-attribute-value structures often found in laboratory data. Moreover, it facilitates the iterative refinement of data representations in the target platforms, as the required configuration files are very compact. The quantitative measurements presented are consistent with our experiences of significantly reduced efforts for building warehousing platforms in close cooperation with medical researchers. Both the cloud-based hosting infrastructure and the data-loading pipeline are available to the community as open source software with comprehensive documentation. CLINICALTRIAL

Application of minimal mathematical models for the dynamics of the signaling pathway of the p53 - miRNA to the analysis of laboratory data

2021 ◽  
pp. 4-49
Author(s):  
Софья Дмитриевна Сенотрусова ◽  
Ольга Фалалеевна Воропаева ◽  
Юрий Иванович Шокин
Keyword(s):  
Mathematical Models ◽  
Signaling Pathway ◽  
Numerical Solutions ◽  
Laboratory Data ◽  
Minimal Models ◽  
Basic Model ◽  
P53 Signaling ◽  
Wide Range ◽  
P53 Signaling Pathway

Работа посвящена практическому использованию минимальных математических моделей динамики сигнального пути p53 для описания достаточно широкого круга лабораторных экспериментов, в которых взаимодействие p53 и белковингибиторов p53 опосредуется микроРНК, образующими с p53 петлю положительной обратной связи. Представлены базовая модель, разработанные на ее основе новые минимальные модели, алгоритм численного решения прямых и обратных коэффициентных задач и результаты сопоставления полученных численных решений с экспериментальными данными о динамике уровней белков p53, p21, Bax, белков-ингибиторов Mdm2, Wip1, Sirt1 и различных микроРНК (miR-16, miR-34a, miR-192, miR-194, miR-215) в условиях стрессовых воздействий. С привлечением полученных математических моделей исследованы базовые механизмы функционирования сигнального пути p53 в условиях, приближенных к условиям конкретных лабораторных экспериментов in vitro и in vivo. Продемонстрированы синергический эффект гиперактивации сигнального пути p53, в котором задействованы микроРНК, и механизмы бимодального переключения. Показана ключевая роль p53-зависимых микроРНК в реализации некоторых гипотетических терапевтических стратегий, связанных с управлением механизмом активации апоптоза клеток. В рамках принятой базовой модели даны оценки вероятности рассогласования в диагностике дегенеративных заболеваний, основанной на анализе уровня p53зависимых микроРНК и p53, при слабой и умеренной дерегуляции микроРНК. This study addresses the practical use of minimal mathematical models of the dynamics of a hypothetical system of the p53 signaling pathway to describe a fairly wide range of laboratory experiments. In such system, the interaction of p53 and p53 inhibitor proteins is mediated by microRNAs that form a positive feedback loop with p53. A basic model, new minimal models developed on its basis, an algorithm for the numerical solution of direct and inverse coefficient problems, and the results of comparing the obtained numerical solutions with experimental data on the dynamics of the levels of p53, p21, Bax proteins, inhibitor proteins Mdm2, Wip1, Sirt1, and various microRNAs (miR-16, miR-34a, miR-192, miR-194, miR-215) under stress conditions are presented. In numerical experiments, the main mechanisms of the p53 signaling pathway were investigated. A synergistic effect of hyperactivation of the p53 signaling pathway and bimodal switching mechanisms has been demonstrated. We show the key role of p53-dependent microRNAs in the implementation of some hypothetical therapeutic strategies associated with the control mechanism for activation of cells apoptosis. Within the framework of the accepted basic model, we estimated the probability of mismatch in the diagnosis of the patient’s status. The status is based on the analysis of the level of p53-dependent microRNAs and p53, with weak and moderate deregulation of microRNAs.

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