bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear Optical and Spectroscopical Properties of Functionalized Oligoanilines
Authors: De A. Machado Ana E. , Da Silva Juliana A. B. , De Almeida Wagner B. , Dos Santos Hélio F. 
Published: January 2021

AbstractFunctionalized octamers of polyaniline neutral forms (leucoemeraldine, emeraldine, pernigraniline) were studied in order to optimize the first hyperpolarizabilities (β). Remarkable static β values were found for the pernigraniline and emeraldine derivatives by using the coupled perturbed Kohn‐Sham (CPKS) approach at the PBE1PBE/6‐31G** level. The enhanced nonlinear response was achieved through the introduction of donor (D) and/or acceptor (A) groups into the oligoanilines structures. The nonlinear optical (NLO) properties of the octamers missing the substituent groups were also investigated. The largest β values were obtained for the pernigraniline and emeraldine derivatives having the tert‐butyl (D) and dicyanoethenyl (A) substituents at opposite ends, as well as the ones with only the acceptor group. These oligomers show charge transfer transitions with large oscillator strengths according to the time dependent density functional theory (TD‐DFT). Predicted β values for the majority of functionalized oligoanilines strongly indicate them as potential building blocks for molecular‐based nonlinear materials with second‐order response.
Synergistically Converting Carbon Dioxide into Cyclic Carbonates by Metalloporphyrin‐Based Cationic Polymers with Imidazolium Functionality
Authors: Liu Xiangying , Zhou Farong , Chen Min , Xu Wei , Liu Hongbo , Zhong Jianjiao , Luo Rongchang 
Published: January 2021

AbstractConsidering to the synergistic activation behavior in the cycloaddition reaction of CO2 to epoxides, the integration of metalloporphyrins and nucleophilic halide anions to afford functional organic polymers is one of the most important approaches and still remains challenging. Herein, a class of novel porphyrin‐based cationic polymer (Por‐CP) has been successfully prepared through a one‐pot and atom‐efficient polycondensation of pyrrole and tailorable imidazolium‐based ionic liquid bearing trialdehyde groups in refluxed propanoic acid. Subsequently, a direct metalation of Por‐CP with zinc acetate resulted in the formation of a zinc porphyrin‐based cationic polymer (ZnPor‐CP). The rigid and charged ZnPor‐CP having spatially‐separated active Zn‐porphyrin sites and abundant imidazolium functionalities in the covalently‐linked skeletons can cooperatively promote the reaction under mild conditions, thereby achieving an efficient unification of high activity and good recyclability.
Lithium Ion Conduction in Diblock Polymer Electrolyte with Tethered Anion
Authors: He Yubin , Liu Nian , Kohl Paul A. 
Published: January 2021

AbstractSolid polymer electrolyte (SPE) may provide a path for next generation high‐performance, hazard‐free lithium ion batteries. However, the low lithium ion transference number (tLi+) and electrolyte conductivity limit device performance. In this study, a diblock copolymer with a polycarbonate first block and poly(sulfonated styrene) second block has been synthesized and characterized for conductivity and shows improved tLi+. The low dissociation of lithium salts from the tethered sulfonate anion was overcome by incorporating plasticizers. The diblock SPE material had room temperature conductivity of up to 1.95 ⋅ 10−6 S/cm, and lithium transference number of up to 0.83 with the tethered sulfonate anion.
A Study of the Lack of Slow Magnetic Relaxation in Mononuclear Trigonal Bipyramidal Cobalt(II) Complexes
Authors: Świtlicka Anna , Machura Barbara , Cano Joan , Lloret Francesc , Julve Miguel 
Published: January 2021

AbstractTwo complexes of formula [Co(H2tba)(N3)]⋅MeOH (1) and [Co(H2tba)(NCS)] ⋅ 2DMF (2) [H3tba=tris(2‐benzimidazolylmethyl)amine] were prepared and characterized aiming at investigating the influence of the structural and chemical effects on the Ising‐type magnetic anisotropy in mononuclear trigonal bipyramidal cobalt(II) complexes. Each cobalt(II) ion in 1 is five‐coordinate by a monodentate azide ligand and a tetradentate monodeprotonated H2tba‐ group building a slightly distorted trigonal bipyramidal surrounding. Compound 2 is also a mononuclear species whose structure was previously reported and only some of its structural data are considered in this work for comparative purposes. Detailed dc and ac cryomagnetic measurements of 1 and 2 show the lack of slow magnetic relaxation both in the presence and absence of applied dc fields. The profile of the χMT against T plots together with the non‐superimposable M against H/T curves for 1 and 2 support the occurrence of high‐spin Co(II) ions with an appreciable magnetic anisotropy. Q‐band EPR studies on polycrystalline samples of these compounds at low temperatures confirm the positive value of the zero‐field splitting (D), a strong asymmetry in the g‐tensors and hence an easy plane of magnetization indicating stabilization of MS=±1/2 sublevels of the S=3/2 spin state. A comparison of our results with previous magneto‐structural reports on mononuclear trigonal bipyramidal cobalt(II) complexes that exhibit slow relaxation of the magnetization is carried out in order get deeper insights about the electronic and structural factors that would be at the origin of the lack of Single‐Ion Magnet (SIM) behaviour for 1 and 2.
Direct Growth of Si, Ge, and Si–Ge Heterostructure Nanowires Using Electroplated Zn: An Inexpensive Seeding Technique for Li‐Ion Alloying Anodes
Authors: Kilian Seamus , McCarthy Kieran , Stokes Killian , Adegoke Temilade Esther , Conroy Michele , Amiinu Ibrahim Saana , Geaney Hugh , Kennedy Tadhg , Ryan Kevin M. 
Published: January 2021

AbstractA scalable and cost‐effective process is used to electroplate metallic Zn seeds on stainless steel substrates. Si and Ge nanowires (NWs) are subsequently grown by placing the electroplated substrates in the solution phase of a refluxing organic solvent at temperatures >430 °C and injecting the respective liquid precursors. The native oxide layer formed on reactive metals such as Zn can obstruct NW growth and is removed in situ by injecting the reducing agent LiBH4. The findings show that the use of Zn as a catalyst produces defect‐rich Si NWs that can be extended to the synthesis of Si–Ge axial heterostructure NWs with an atomically abrupt Si–Ge interface. As an anode material, the as grown Zn seeded Si NWs yield an initial discharge capacity of 1772 mAh g−1 and a high capacity retention of 85% after 100 cycles with the active participation of both Si and Zn during cycling. Notably, the Zn seeds actively participate in the Li‐cycling activities by incorporating into the Si NWs body via a Li‐assisted welding process, resulting in restructuring the NWs into a highly porous network structure that maintains a stable cycling performance.
A proposed medication score for long‐term trials of treatment of canine atopic dermatitis sensu lato
Authors: Saridomichelakis Manolis N. , Favrot Claude , Jackson Hilary A. , Bensignor Emmanuel , Prost Christine , Mueller Ralf S. 
Published: January 2021

AbstractBackground: The use of concurrent medications is necessary in trials of treatment of canine atopic dermatitis. Our aim was to use the best available evidence to construct and then to validate a medication score (MS) formula that will estimate the impact of concurrent medications on trial outcomes.Methods: Trials of 15 interventions were scrutinized to find those that were consistent in terms of specific medication, administration route and dosage regimen. A MS was constructed in five steps, starting from assigning a score of 1 for each day on oral prednisone, prednisolone or methylprednisolone at 0.5–1.0 mg/kg. The MS score was validated using the clinical records of 35 dogs with atopic dermatitis that had been treated for a period of 12 ± 2 weeks with six of these medications and compared with a previously published non‐validated MS.Results: A MS could be assigned to eight treatments, six of which had been administered to the 35 dogs. A positive correlation was seen with the previously published MS and a negative correlation with changes in lesional and pruritus scores.Conclusion: This MS may be a useful tool in new studies evaluating the efficacy of treatments in canine atopic dermatitis
Renal pH Imaging Using Chemical Exchange Saturation Transfer (CEST) MRI: Basic Concept
Authors: Longo Dario Livio , Irrera Pietro , Consolino Lorena , Sun Phillip Zhe , McMahon Michael T. 
Published: January 2021

AbstractMagnetic Resonance Imaging (MRI) has been actively explored in the last several decades for assessing renal function by providing several physiological information, including glomerular filtration rate, renal plasma flow, tissue oxygenation and water diffusion. Within MRI, the developing field of chemical exchange saturation transfer (CEST) has potential to provide further functional information for diagnosing kidney diseases. Both endogenous produced molecules as well as exogenously administered CEST agents have been exploited for providing functional information related to kidney diseases in preclinical studies. In particular, CEST MRI has been exploited for assessing the acid-base homeostasis in the kidney and for monitoring pH changes in several disease models. This review summarizes several CEST MRI procedures for assessing kidney functionality and pH, for monitoring renal pH changes in different kidney injury models and for evaluating renal allograft rejection.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.
Functional Imaging Using Fluorine (19F) MR Methods: Basic Concepts
Authors: Waiczies Sonia , Prinz Christian , Starke Ludger , Millward Jason M. , Delgado Paula Ramos , Rosenberg Jens , Nazaré Marc , Waiczies Helmar , Pohlmann Andreas , Niendorf Thoralf 
Published: January 2021

AbstractKidney-associated pathologies would greatly benefit from noninvasive and robust methods that can objectively quantify changes in renal function. In the past years there has been a growing incentive to develop new applications for fluorine (19F) MRI in biomedical research to study functional changes during disease states. 19F MRI represents an instrumental tool for the quantification of exogenous 19F substances in vivo. One of the major benefits of 19F MRI is that fluorine in its organic form is absent in eukaryotic cells. Therefore, the introduction of exogenous 19F signals in vivo will yield background-free images, thus providing highly selective detection with absolute specificity in vivo. Here we introduce the concept of 19F MRI, describe existing challenges, especially those pertaining to signal sensitivity, and give an overview of preclinical applications to illustrate the utility and applicability of this technique for measuring renal function in animal models.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.
Assessment of Renal Volume with MRI: Experimental Protocol
Authors: Müller Andreas , Meier Martin 
Published: January 2021

AbstractRenal length and volume are important parameters in the clinical assessment of patients with diabetes mellitus, kidney transplants, or renal artery stenosis. Kidney size is used in primary diagnostics to differentiate between acute (rather swollen kidneys) and chronic (rather small kidney) pathophysiology. Total kidney volume is also an established biomarker in studies for the treatment of autosomal dominant polycystic kidney disease (ADPKD). There are several factors influencing kidney size, and there is still a debate on the value of the measured kidney size in terms of renal function or cardiovascular risk. The renal volume is most often calculated by measuring the three axes of the kidney, on the assumption that the organ resembles an ellipsoid. By default, the longitudinal and transverse diameters of the kidney are measured. In animal models renal length and volume1are also important parameters in the assessment of organ rejection after transplantation and in determination of kidney failure due to renal artery stenosis, recurrent urinary tract infections, or diabetes mellitus. In general total kidney volume (TKV) is a valuable parameter for predicting prognosis and monitoring disease progression in animal models of human diseases like polycystic kidney disease (PKD) or acute kidney injury (AKI) and chronic kidney disease (CKD).This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This analysis protocol is complemented by two separate chapters describing the basic concept and experimental procedure.
Dynamic Contrast Enhanced (DCE) MRI-Derived Renal Perfusion and Filtration: Experimental Protocol
Authors: Irrera Pietro , Consolino Lorena , Dastrù Walter , Pedersen Michael , Zöllner Frank G. , Longo Dario Livio 
Published: January 2021

AbstractDynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can provide a noninvasive way for assessing renal functional information following the administration of a small molecular weight gadolinium-based contrast agent. This method may be useful for investigating renal perfusion and glomerular filtration rates of rodents in vivo under various experimental (patho)physiological conditions. Here we describe a step-by-step protocol for DCE-MRI studies in small animals providing practical notes on acquisition parameters, sequences, T1 mapping approaches and procedures.This chapters is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by two separate chapters describing the basic concept and data analysis.
Fluorine (19F) MRI for Assessing Inflammatory Cells in the Kidney: Experimental Protocol
Authors: Ku Min-Chi , Schreiber Adrian , Delgado Paula Ramos , Boehm-Sturm Philipp , Kettritz Ralph , Niendorf Thoralf , Pohlmann Andreas , Waiczies Sonia 
Published: January 2021

AbstractInflammation is one underlying contributing factor in the pathology of acute and chronic kidney disorders. Phagocytes such as monocytes, neutrophils and dendritic cells are considered to play a deleterious role in the progression of kidney disease but may also contribute to organ homeostasis. The kidney is a target of life-threatening autoimmune disorders such as the antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV). Neutrophils and monocytes express ANCA antigens and play an important role in the pathogenesis of AAV. Noninvasive in vivo methods that can quantify the distribution of inflammatory cells in the kidney as well as other organs in vivo would be vital to identify the causality and significance of inflammation during disease progression. Here we describe an noninvasive technique to study renal inflammation in rodents in vivo using fluorine (19F) MRI. In this protocol we chose a murine ANCA-AAV model of renal inflammation and made use of nanoparticles prepared from perfluoro-5-crown-15-ether (PFCE) for renal 19F MRI.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by two separate chapters describing the basic concept and data analysis.
Subsegmentation of the Kidney in Experimental MR Images Using Morphology-Based Regions-of-Interest or Multiple-Layer Concentric Objects
Authors: Riazy Leili , Milani Bastien , Periquito João S. , Cantow Kathleen , Niendorf Thoralf , Pruijm Menno , Seeliger Erdmann , Pohlmann Andreas 
Published: January 2021

AbstractFunctional renal MRI promises access to a wide range of physiologically relevant parameters such as blood oxygenation, perfusion, tissue microstructure, pH, and sodium concentration. For quantitative comparison of results, representative values must be extracted from the parametric maps obtained with these different MRI techniques. To improve reproducibility of results this should be done based on regions-of-interest (ROIs) that are clearly and objectively defined.Semiautomated subsegmentation of the kidney in magnetic resonance images represents a simple but very valuable approach for the quantitative analysis of imaging parameters in multiple ROIs that are associated with specific anatomic locations. Thereby, it facilitates comparing MR parameters between different kidney regions, as well as tracking changes over time.Here we provide detailed step-by-step instructions for two recently developed subsegmentation techniques that are suitable for kidneys of small rodents: i) the placement of ROIs in cortex, outer and the inner medulla based on typical kidney morphology and ii) the division of the kidney into concentrically oriented layers.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers.
Analysis Protocols for MRI Mapping of the Blood Oxygenation–Sensitive Parameters T2* and T2 in the Kidney
Authors: Periquito João S. , Starke Ludger , Santos Carlota M. , Freitas Andreia C. , Loução Nuno , Polo Pablo García , Nunes Rita G. , Niendorf Thoralf , Pohlmann Andreas 
Published: January 2021

AbstractRenal hypoxia is generally accepted as a key pathophysiologic event in acute kidney injury of various origins and has also been suggested to play a role in the development of chronic kidney disease. Here we describe step-by-step data analysis protocols for MRI monitoring of renal oxygenation in rodents via the deoxyhemoglobin concentration sensitive MR parameters T2* and T2—a contrast mechanism known as the blood oxygenation level dependent (BOLD) effect.This chapter describes how to use the analysis tools provided by vendors of animal and clinical MR systems, as well as how to develop an analysis software. Aspects covered are: data quality checks, data exclusion, model fitting, fitting algorithm, starting values, effects of multiecho imaging, and result validation.This chapter is based upon work from the PARENCHIMA COST Action, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by two separate chapters describing the basic concept and data analysis.
Analysis of Renal Diffusion-Weighted Imaging (DWI) Using Apparent Diffusion Coefficient (ADC) and Intravoxel Incoherent Motion (IVIM) Models
Authors: Jerome Neil Peter , Periquito João S. 
Published: January 2021

AbstractAnalysis of renal diffusion-weighted imaging (DWI) data to derive markers of tissue properties requires careful consideration of the type, extent, and limitations of the acquired data. Alongside data quality and general suitability for quantitative analysis, choice of diffusion model, fitting algorithm, and processing steps can have consequences for the precision, accuracy, and reliability of derived diffusion parameters. Here we introduce and discuss important steps for diffusion-weighted image processing, and in particular give example analysis protocols and pseudo-code for analysis using the apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM) models. Following an overview of general principles, we provide details of optional steps, and steps for validation of results. Illustrative examples are provided, together with extensive notes discussing wider context of individual steps, and notes on potential pitfalls.This publication is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This analysis protocol chapter is complemented by two separate chapters describing the basic concepts and experimental procedure.
Analysis Protocol for Dynamic Contrast Enhanced (DCE) MRI of Renal Perfusion and Filtration
Authors: Zöllner Frank G. , Dastrù Walter , Irrera Pietro , Longo Dario Livio , Bennett Kevin M. , Beeman Scott C. , Bretthorst G. Larry , Garbow Joel R. 
Published: January 2021

AbstractHere we present an analysis protocol for dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) data of the kidneys. It covers comprehensive steps to facilitate signal to contrast agent concentration mapping via T1 mapping and the calculation of renal perfusion and filtration parametric maps using model-free approaches, model free analysis using deconvolution, the Toft’s model and a Bayesian approach.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This analysis protocol chapter is complemented by two separate chapters describing the basic concept and experimental procedure.
Preparation of Ex Vivo Rodent Phantoms for Developing, Testing, and Training MR Imaging of the Kidney and Other Organs
Authors: Millward Jason M. , Periquito João S. , Delgado Paula Ramos , Prinz Christian , Niendorf Thoralf , Waiczies Sonia 
Published: January 2021

AbstractHere we describe a simple and inexpensive protocol for preparing ex vivo rodent phantoms for use in MR imaging studies. The experimental animals are perfused and fixed with formaldehyde, and then wrapped with gauze and sealed with liquid latex. This yields a phantom that preserves all organs in situ, and which avoids the need to keep fixed animals and organs in containers that have dimensions very different from living animals. This is especially important for loading in MR detectors, and specifically the RF coils, they are usually used with. The phantom can be safely stored and conveniently reused, and can provide MR scientists with a realistic phantom with which to establish protocols in preparation for preclinical in vivo studies—for renal, brain, and body imaging. The phantom also serves as an ideal teaching tool, for trainees learning how to perform preclinical MRI investigations of the kidney and other target organs, while avoiding the need for handling living animals, and reducing the total number of animals required.This protocol chapter is part of the PARENCHIMA initiative “MRI Biomarkers for CKD” (CA16103), a community-driven Action of the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers.