scholarly journals Stimuli-Responsive Zinc (II) Coordination Polymers: A Novel Platform for Supramolecular Chromic Smart Tools

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3712
Author(s):  
Rosita Diana ◽  
Ugo Caruso ◽  
Barbara Panunzi
Keyword(s):  
Cross Section ◽  
Coordination Polymers ◽  
Imaging Technique ◽  
Stimuli Responsive ◽  
Advanced Imaging ◽  
Coordination Environment ◽  
Unique Role ◽  
Responsive Materials ◽  
The Past

The unique role of the zinc (II) cation prompted us to cut a cross-section of the large and complex topic of the stimuli-responsive coordination polymers (CPs). Due to its flexible coordination environment and geometries, easiness of coordination–decoordination equilibria, “optically innocent” ability to “clip” the ligands in emissive architectures, non-toxicity and sustainability, the zinc (II) cation is a good candidate for building supramolecular smart tools. The review summarizes the recent achievements of zinc-based CPs as stimuli-responsive materials able to provide a chromic response. An overview of the past five years has been organised, encompassing 1, 2 and 3D responsive zinc-based CPs; specifically zinc-based metallorganic frameworks and zinc-based nanosized polymeric probes. The most relevant examples were collected following a consequential and progressive approach, referring to the structure–responsiveness relationship, the sensing mechanisms, the analytes and/or parameters detected. Finally, applications of highly bioengineered Zn-CPs for advanced imaging technique have been discussed.

Lattice solvent controlled photochromism of tripyridyl-triazine-based zinc bromide complexes

2022 ◽  
Author(s):  
Pengfei Hao ◽  
Xing Liu ◽  
Chunyu Guo ◽  
Guozheng Zhao ◽  
Gao-Peng Li ◽  
...  
Keyword(s):  
Stimuli Responsive ◽  
Zinc Bromide ◽  
Responsive Materials ◽  
The Past

The development of new stimuli-responsive materials with controllable properties has been highly desirable in the past decade owing to their increasing application demand in various areas. In this work, two...

scholarly journals Mechanical Bending and Modulation of Photoactuation Properties in a One-Dimensional Pb(II) Coordination Polymer

2021 ◽  
Author(s):  
Bibhuti Bhusan Rath ◽  
Jagadese J. Vittal
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Coordination Polymer ◽  
Elastic Deformation ◽  
Coordination Polymers ◽  
Stimuli Responsive ◽  
Responsive Materials ◽  
One Dimensional ◽  
Different Shapes ◽  
Mechanical Bending

With emergent research on stimuli responsive materials, dynamic crystals are at the forefront of investigation. However, research on the mechanical properties of coordination polymers (CPs) is still in its infancy. Elastic deformation induced by pressure and photoactuation are rare occurrences in CPs, let alone their combination in a single CP. Here, we report a one-dimensional (1D) CP comprising PbBr2 chains with 3-fluoro-4’-styrylpyridine arms showing excellent elasticity and photomechanical properties. A slender crystal can be bent to make a circle and write different shapes with restoration of original shape upon removal of the applied force. In addition, photomechanical properties triggered by [2+2] cycloaddition of the olefinic ligand can be modulated easily by variation of the crystal sizes. Crystals with bigger width show destructive photosalient effects while the smaller ones show plastic deformation like bending, twisting, curling etc. upon UV irradiation. This example provides avenue for designing CPs for multi-stimuli responsive actuating properties.

Organized Outpatient Care of Patients with Transient Ischemic Attack and Minor Stroke

2017 ◽  
Vol 37 (03) ◽  
pp. 383-390 ◽  
Author(s):  
R. Joundi ◽  
G. Saposnik
Keyword(s):  
Transient Ischemic Attack ◽  
Recurrent Stroke ◽  
Scoring Systems ◽  
Medical Emergency ◽  
Minor Stroke ◽  
Specialist Care ◽  
Advanced Imaging ◽  
The Past ◽  
Ischemic Attack

AbstractThe risk of recurrent stroke after transient ischemic attack (TIA) is high. In the past 10 years, TIA has increasingly been recognized as a medical emergency. Health systems have adapted toward rapid evaluation, investigation, and secondary prevention in patients with presumed TIA and minor stroke, and the significant benefits in reducing recurrent stroke and mortality have been borne out in several landmark studies. Various scores have been developed and debated to better risk stratify patients with TIA for hospitalization or urgent referral. However, scoring systems face challenges in identifying all patients with high-risk etiologies such as atrial fibrillation and carotid stenosis, and therefore require further refinement before widespread use. Further challenges include the role of advanced imaging in TIA, and ensuring rapid access to specialist care for all patients. In the absence of definitive risk stratification methods, the authors conclude that all patients with suspected TIA and minor stroke should be assessed and treated on an urgent basis, ideally through rapid outpatient referral programs.

The influence of different coordination environments on one-dimensional Cu(ii) coordination polymers for the photo-degradation of organic dyes

2016 ◽  
Vol 45 (18) ◽  
pp. 7697-7707 ◽  
Author(s):  
Navid Hussain ◽  
Vimal K. Bhardwaj
Keyword(s):  
Coordination Polymers ◽  
Organic Dyes ◽  
Polymeric Complex ◽  
Photo Degradation ◽  
Coordination Environment ◽  
One Dimensional ◽  
Photo Catalytic Activity ◽  
Catalytic Rate Constant ◽  
Catalytic Rate

The role of coordination environment in 1D Cu(ii) coordination polymers for photo-catalytic activity has been investigated. Pyridine-2,6-dicarbohydrazide based polymeric complex 3 has the highest photo-catalytic rate constant (k = 0.72 h−1) for rhodamine B degradation.

scholarly journals Mechanical Bending and Modulation of Photoactuation Properties in a One-Dimensional Pb(II) Coordination Polymer

2021 ◽  
Author(s):  
Bibhuti Bhusan Rath ◽  
Jagadese J. Vittal
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Coordination Polymer ◽  
Elastic Deformation ◽  
Coordination Polymers ◽  
Stimuli Responsive ◽  
Responsive Materials ◽  
One Dimensional ◽  
Different Shapes ◽  
Mechanical Bending

With emergent research on stimuli responsive materials, dynamic crystals are at the forefront of investigation. However, research on the mechanical properties of coordination polymers (CPs) is still in its infancy. Elastic deformation induced by pressure and photoactuation are rare occurrences in CPs, let alone their combination in a single CP. Here, we report a one-dimensional (1D) CP comprising PbBr2 chains with 3-fluoro-4’-styrylpyridine arms showing excellent elasticity and photomechanical properties. A slender crystal can be bent to make a circle and write different shapes with restoration of original shape upon removal of the applied force. In addition, photomechanical properties triggered by [2+2] cycloaddition of the olefinic ligand can be modulated easily by variation of the crystal sizes. Crystals with bigger width show destructive photosalient effects while the smaller ones show plastic deformation like bending, twisting, curling etc. upon UV irradiation. This example provides avenue for designing CPs for multi-stimuli responsive actuating properties.

On Future Directions in Pathology

1982 ◽  
Vol 40 ◽  
pp. 274-277
Author(s):  
Benjamin F. Trump ◽  
Irene K. Berezesky ◽  
Raymond T. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Clinical Pathology ◽  
Future Directions ◽  
Diagnostic Pathology ◽  
The Past ◽  
Transmission Electron ◽  
Organ Systems ◽  
The Many

The role of electron microscopy and associated techniques is assured in diagnostic pathology. At the present time, most of the progress has been made on tissues examined by transmission electron microscopy (TEM) and correlated with light microscopy (LM) and by cytochemistry using both plastic and paraffin-embedded materials. As mentioned elsewhere in this symposium, this has revolutionized many fields of pathology including diagnostic, anatomic and clinical pathology. It began with the kidney; however, it has now been extended to most other organ systems and to tumor diagnosis in general. The results of the past few years tend to indicate the future directions and needs of this expanding field. Now, in addition to routine EM, pathologists have access to the many newly developed methods and instruments mentioned below which should aid considerably not only in diagnostic pathology but in investigative pathology as well.

Oxygen K near edge structures studied with multiple scattering calculations

1988 ◽  
Vol 46 ◽  
pp. 504-505
Author(s):  
Xudong Weng ◽  
Peter Rez
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Partial Cross Section ◽  
Energy Window ◽  
Edge Structure ◽  
Fine Structures ◽  
Hydrogenic Model ◽  
Electron Energy Loss ◽  
Quantitative Chemical

In electron energy loss spectroscopy, quantitative chemical microanalysis is performed by comparison of the intensity under a specific inner shell edge with the corresponding partial cross section. There are two commonly used models for calculations of atomic partial cross sections, the hydrogenic model and the Hartree-Slater model. Partial cross sections could also be measured from standards of known compositions. These partial cross sections are complicated by variations in the edge shapes, such as the near edge structure (ELNES) and extended fine structures (ELEXFS). The role of these solid state effects in the partial cross sections, and the transferability of the partial cross sections from material to material, has yet to be fully explored. In this work, we consider the oxygen K edge in several oxides as oxygen is present in many materials. Since the energy window of interest is in the range of 20-100 eV, we limit ourselves to the near edge structures.

Meiotic CENP-C is a shepherd: bridging the space between the centromere and the kinetochore in time and space

2020 ◽  
Vol 64 (2) ◽  
pp. 251-261
Author(s):  
Jessica E. Fellmeth ◽  
Kim S. McKim
Keyword(s):  
Chromosome Segregation ◽  
New Technologies ◽  
Early Prophase ◽  
Unique Role ◽  
Kinetochore Assembly ◽  
M Phase ◽  
In Vivo Analysis ◽  
Meiosis I

Abstract While many of the proteins involved in the mitotic centromere and kinetochore are conserved in meiosis, they often gain a novel function due to the unique needs of homolog segregation during meiosis I (MI). CENP-C is a critical component of the centromere for kinetochore assembly in mitosis. Recent work, however, has highlighted the unique features of meiotic CENP-C. Centromere establishment and stability require CENP-C loading at the centromere for CENP-A function. Pre-meiotic loading of proteins necessary for homolog recombination as well as cohesion also rely on CENP-C, as do the main scaffolding components of the kinetochore. Much of this work relies on new technologies that enable in vivo analysis of meiosis like never before. Here, we strive to highlight the unique role of this highly conserved centromere protein that loads on to centromeres prior to M-phase onset, but continues to perform critical functions through chromosome segregation. CENP-C is not merely a structural link between the centromere and the kinetochore, but also a functional one joining the processes of early prophase homolog synapsis to late metaphase kinetochore assembly and signaling.

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