Total angular momenta quantization of dielectric sphere modes

Abstract Spherical particles both dielectric and metallic are essential building blocks in nanophotonics. During the recent rapid development of Mie-tronic — nanophotonics devices heavily using various features of the Mie-resonances — the deep fundamental investigation of the eigenmodes of such particles by using the novel tools is still relevant and currently important. Moreover, eigenmodes of a sphere are closely related to the Vector Spherical Harmonics (VSH) which are widely used in the multipolar decomposition to analyze less symmetric structures. In this work, we study in detail the canonical spin and angular momenta (AM), helicity, and other properties of the eigenmodes of dielectric (nondispersive) and metallic (dispersive) spheres. We show that the canonical momentum density of the AM is quantized and has a close relation to the quantum picture of a single photon. Our work provides a solid platform for future studies and applications of the AM transfer from near fields of spherical particles to the matter in its vicinity.

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The Role of Neuroimaging in the Diagnosis and Treatment of Depressive Disorder: A Recent Review

Current Pharmaceutical Design ◽

10.2174/1381612824666180727111142 ◽

2018 ◽

Vol 24 (22) ◽

pp. 2515-2523 ◽

Cited By ~ 4

Author(s):

Tianbin Song ◽

Xiaowei Han ◽

Lei Du ◽

Jing Che ◽

Jing Liu ◽

...

Keyword(s):

Magnetic Resonance ◽

Depressive Disorder ◽

Diffusion Tensor ◽

Single Photon ◽

Rapid Development ◽

Photon Emission ◽

Clinical Manifestations ◽

Brain Network ◽

Emission Computed Tomography ◽

Resonance Spectroscopy

Depression is a mental disorder with serious negative health outcomes. Its main clinical manifestations are depressed mood, slow thinking, loss of interest, and lack of energy. The rising incidence of depression has a major impact on patients and their families and imposes a substantial burden on society. With the rapid development of imaging technology in recent years, researchers have studied depression from different perspectives, including molecular, functional, and structural imaging. Many studies have revealed changes in structure, function, and metabolism in various brain regions in patients with depressive disorder. In this review, we summarize relevant studies of depression, including investigations using structural magnetic resonance imaging (MRI), functional MRI (task-state fMRI and resting-state fMRI), diffusion tensor imaging (DTI), magnetic resonance spectroscopy (MRS), brain network and molecular imaging (positron emission tomography [PET] and single photon emission computed tomography [SPECT]), which have contributed to our understanding of the etiology, neuropathology, and pathogenesis of depressive disorder.

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Single-Photon Detection Module Based on Large-Area Silicon Photomultipliers for Time-Domain Diffuse Optics

Instruments ◽

10.3390/instruments5020018 ◽

2021 ◽

Vol 5 (2) ◽

pp. 18

Author(s):

Fabio Acerbi ◽

Anurag Behera ◽

Alberto Dalla Mora ◽

Laura Di Sieno ◽

Alberto Gola

Keyword(s):

Time Resolution ◽

Time Domain ◽

Single Photon ◽

Building Blocks ◽

The Body ◽

Single Photon Detection ◽

Silicon Photomultipliers ◽

Photon Detection ◽

Instrument Response Function ◽

Diffuse Optics

Silicon photomultipliers (SiPM) are pixelated single-photon detectors combining high sensitivity, good time resolution and high dynamic range. They are emerging in many fields, such as time-domain diffuse optics (TD-DO). This is a promising technique in neurology, oncology, and quality assessment of food, wood, and pharmaceuticals. SiPMs can have very large areas and can significantly increase the sensitivity of TD-DO in tissue investigation. However, such improvement is currently limited by the high detector noise and the worsening of SiPM single-photon time resolution due to the large parasitic capacitances. To overcome such limitation, in this paper, we present two single-photon detection modules, based on 6 × 6 mm2 and 10 × 10 mm2 SiPMs, housed in vacuum-sealed TO packages, cooled to −15 °C and −36 °C, respectively. They integrate front-end amplifiers and temperature controllers, being very useful instruments for TD-DO and other biological and physical applications. The signal extraction from the SiPM was improved. The noise is reduced by more than two orders of magnitude compared to the room temperature level. The full suitability of the proposed detectors for TD-DO measurements is outside the scope of this work, but preliminary tests were performed analyzing the shape and the stability of the Instrument Response Function. The proposed modules are thus fundamental building blocks to push the TD-DO towards deeper investigations inside the body.

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Characterization of the SARS-CoV-2 coronavirus X4-like accessory protein

Egyptian Journal of Medical Human Genetics ◽

10.1186/s43042-021-00160-1 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Olanrewaju Ayodeji Durojaye ◽

Nkwachukwu Oziamara Okoro ◽

Arome Solomon Odiba

Keyword(s):

Rapid Development ◽

Protein A ◽

The Novel ◽

Quality Model ◽

A Value ◽

Model Protein ◽

Novel Coronavirus ◽

Global Threat

Abstract Background The novel coronavirus SARS-CoV-2 is currently a global threat to health and economies. Therapeutics and vaccines are in rapid development; however, none of these therapeutics are considered as absolute cure, and the potential to mutate makes it necessary to find therapeutics that target a highly conserved regions of the viral structure. Results In this study, we characterized an essential but poorly understood coronavirus accessory X4 protein, a core and stable component of the SARS-CoV family. Sequence analysis shows a conserved ~ 90% identity between the SARS-CoV-2 and previously characterized X4 protein in the database. QMEAN Z score of the model protein shows a value of around 0.5, within the acceptable range 0–1. A MolProbity score of 2.96 was obtained for the model protein and indicates a good quality model. The model has Ramachandran values of φ = − 57o and ψ = − 47o for α-helices and values of φ = − 130o and ψ = + 140o for twisted sheets. Conclusions The protein data obtained from this study provides robust information for further in vitro and in vivo experiment, targeted at devising therapeutics against the virus. Phylogenetic analysis further supports previous evidence that the SARS-CoV-2 is positioned with the SL-CoVZC45, BtRs-BetaCoV/YN2018B and the RS4231 Bat SARS-like corona viruses.

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Sophorolipid-Based Oligomers as Polyol Components for Polyurethane Systems

Polymers ◽

10.3390/polym13122001 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2001

Author(s):

Maresa Sonnabend ◽

Suzanne G. Aubin ◽

Annette M. Schmidt ◽

Marc C. Leimenstoll

Keyword(s):

Special Property ◽

Building Blocks ◽

Conservation Of Resources ◽

The Novel ◽

Carbon Footprints ◽

Proper Design ◽

Chemical Products ◽

Hydroxyl Fatty Acids ◽

New Applications ◽

Novel Products

Due to reasons of sustainability and conservation of resources, polyurethane (PU)-based systems with preferably neutral carbon footprints are in increased focus of research and development. The proper design and development of bio-based polyols are of particular interest since such polyols may have special property profiles that allow the novel products to enter new applications. Sophorolipids (SL) represent a bio-based toolbox for polyol building blocks to yield diverse chemical products. For a reasonable evaluation of the potential for PU chemistry, however, further investigations in terms of synthesis, derivatization, reproducibility, and reactivity towards isocyanates are required. It was demonstrated that SL can act as crosslinker or as plasticizer in PU systems depending on employed stoichiometry. (ω-1)-hydroxyl fatty acids can be derived from SL and converted successively to polyester polyols and PU. Additionally, (ω-1)-hydroxyl fatty acid azides can be prepared indirectly from SL and converted to A/B type PU by Curtius rearrangement.

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Droplet-microfluidics towards the assembly of advanced building blocks in cell mimicry

Nanoscale ◽

10.1039/c6nr07807a ◽

2016 ◽

Vol 8 (47) ◽

pp. 19510-19522 ◽

Cited By ~ 10

Author(s):

Adam Armada-Moreira ◽

Essi Taipaleenmäki ◽

Fabian Itel ◽

Yan Zhang ◽

Brigitte Städler

Keyword(s):

Building Blocks ◽

Droplet Microfluidics ◽

Spherical Particles ◽

Recent Developments

This minireview outlines recent developments in droplet microfluidics regarding the assembly of nanoparticles, Janus-shaped and other non-spherical particles, and cargo-loaded particles which could potentially be employed as building blocks in cell mimicry.

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Advanced Thermally Drawn Multimaterial Fibers: Structure-Enabled Functionalities

10.34133/2021/9676470 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Zhe Wang ◽

Mengxiao Chen ◽

Yu Zheng ◽

Jing Zhang ◽

Zhixun Wang ◽

...

Keyword(s):

Optical Fibers ◽

Early Stage ◽

Rapid Development ◽

Wearable Devices ◽

Surface Structures ◽

The Past ◽

High Scalability ◽

Drawing Technique ◽

Symmetric Structures ◽

Thermal Drawing

Thermally drawn multimaterial fibers have experienced rapid development in the past two decades owing to the high scalability, uniformity, and material and structure compatibility of the thermal drawing technique. This article reviews various multimaterial fibers based on different functional structures and their applications in disparate fields. We start from the functional structures achieved in optical fibers developed in the early stage of thermally drawn fibers. Subsequently, we introduce both typical functional structures and unique structures created in multimaterial fibers for varying applications. Next, we present the early attempts in breaking the axial symmetric structures of thermally drawn fibers for extended functionalities. Additionally, we summarize the current progress on creating surface structures on thermally drawn fibers. Finally, we provide an outlook for this trending topic towards wearable devices and smart textiles.

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Radionuclide-Based Imaging of Breast Cancer: State of the Art

Cancers ◽

10.3390/cancers13215459 ◽

2021 ◽

Vol 13 (21) ◽

pp. 5459

Author(s):

Huiling Li ◽

Zhen Liu ◽

Lujie Yuan ◽

Kevin Fan ◽

Yongxue Zhang ◽

...

Keyword(s):

Breast Cancer ◽

Molecular Imaging ◽

Single Photon ◽

Morphological Changes ◽

Imaging Techniques ◽

Rapid Development ◽

Photon Emission ◽

Emission Computed Tomography ◽

Biological Processes ◽

Functional Perspective

Breast cancer is a malignant tumor that can affect women worldwide and endanger their health and wellbeing. Early detection of breast cancer can significantly improve the prognosis and survival rate of patients, but with traditional anatomical imagine methods, it is difficult to detect lesions before morphological changes occur. Radionuclide-based molecular imaging based on positron emission tomography (PET) and single-photon emission computed tomography (SPECT) displays its advantages for detecting breast cancer from a functional perspective. Radionuclide labeling of small metabolic compounds can be used for imaging biological processes, while radionuclide labeling of ligands/antibodies can be used for imaging receptors. Noninvasive visualization of biological processes helps elucidate the metabolic state of breast cancer, while receptor-targeted radionuclide molecular imaging is sensitive and specific for visualization of the overexpressed molecular markers in breast cancer, contributing to early diagnosis and better management of cancer patients. The rapid development of radionuclide probes aids the diagnosis of breast cancer in various aspects. These probes target metabolism, amino acid transporters, cell proliferation, hypoxia, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), gastrin-releasing peptide receptor (GRPR) and so on. This article provides an overview of the development of radionuclide molecular imaging techniques present in preclinical or clinical studies, which are used as tools for early breast cancer diagnosis.

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Preparation and Conductive and Electromagnetic Properties of Fe3O4/PANI Nanocomposite via Reverse In Situ Polymerization

Journal of Nanomaterials ◽

10.1155/2019/7962754 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Di Zhang ◽

Huaiyin Chen ◽

Ruoyu Hong

Keyword(s):

In Situ Polymerization ◽

Rapid Development ◽

Chloroform Solution ◽

Electromagnetic Properties ◽

Network Analyzer ◽

The Novel ◽

Electromagnetic Devices ◽

Ft Ir ◽

Polymerization Method

In this paper, the magnetite/polyaniline (PANI) nanocomposite was prepared by the novel reverse in situ polymerization method. Fe3O4 magnetic nanoparticles were synthesized in situ in PANI chloroform solution to form a suspension containing the Fe3O4/PANI nanocomposite. It overcame the disadvantage of oxidation of the Fe3O4 by the oxidant in conventional method. The Fe3O4/PANI chloroform suspension and the Fe3O4/PANI powder were characterized by FT-IR, TEM, XRD, vibrating sample magnetometer, Gouy magnetic balance, conductivity meter, and vector network analyzer. It is demonstrated that the Fe3O4/PANI suspension has a good electrical conductivity that is up to 2.135 μS/cm at the optimal ratio of reactants. The Fe3O4 nanoparticles are well dispersed in the PANI network with a particle size of about 10 nm. Fe3O4/PANI powder has high saturation magnetization and magnetic susceptibility, as well as a broad application prospect in the field of electromagnetic devices. The Fe3O4/PANI powder exhibits an excellent microwave absorption behavior, which can be an outstanding candidate for the rapid development of broadband shielding materials.

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Effects of Oceanic Turbulence on Orbital Angular Momenta of Optical Communications

Journal of Marine Science and Engineering ◽

10.3390/jmse8110869 ◽

2020 ◽

Vol 8 (11) ◽

pp. 869

Author(s):

Shuang Zhai ◽

Yun Zhu ◽

Yixin Zhang ◽

Zhengda Hu

Keyword(s):

Dissipation Rate ◽

Quantum Coherence ◽

Single Photon ◽

Beam Width ◽

Communication Performance ◽

Oceanic Turbulence ◽

Angular Momenta ◽

Optimal Beam ◽

Lower Temperature ◽

Inner Scale

The propagation properties of Laguerre-Gaussian beams in oceanic turbulence are investigated for both single-photon and biphoton cases. For single-photon communication, the channel capacity and trace distance are employed, both of which effectively reveal the communication performance via different viewpoints. For the biphoton case, we consider distributions of quantum resources including entanglement and quantum coherence. Turbulence conditions with a larger inner-scale and anisotropic factors, higher dissipation rate of kinetic energy, lower dissipation rate of the mean-squared temperature, and lower temperature-salinity contribution ratio combined with longer wavelength and an appropriate range of optimal beam width are beneficial to communication performances. Our results provide theoretical significance to improve the orbital-angular-momentum communication via oceanic turbulence.

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Comparison of Transparency and Shrinkage During Clearing of Insect Brains Using Media With Tunable Refractive Index

Frontiers in Neuroanatomy ◽

10.3389/fnana.2020.599282 ◽

2020 ◽

Vol 14 ◽

Author(s):

Bo M. B. Bekkouche ◽

Helena K. M. Fritz ◽

Elisa Rigosi ◽

David C. O'Carroll

Keyword(s):

Refractive Index ◽

Rapid Development ◽

Vacuum Treatment ◽

Building Blocks ◽

Light Sheet ◽

Tracheal System ◽

Light Sheet Microscopy ◽

Tissue Shrinkage ◽

Tunable Refractive Index ◽

The Brain

Improvement of imaging quality has the potential to visualize previously unseen building blocks of the brain and is therefore one of the great challenges in neuroscience. Rapid development of new tissue clearing techniques in recent years have attempted to solve imaging compromises in thick brain samples, particularly for high resolution optical microscopy, where the clearing medium needs to match the high refractive index of the objective immersion medium. These problems are exacerbated in insect tissue, where numerous (initially air-filled) tracheal tubes branching throughout the brain increase the scattering of light. To date, surprisingly few studies have systematically quantified the benefits of such clearing methods using objective transparency and tissue shrinkage measurements. In this study we compare a traditional and widely used insect clearing medium, methyl salicylate combined with permanent mounting in Permount (“MS/P”) with several more recently applied clearing media that offer tunable refractive index (n): 2,2′-thiodiethanol (TDE), “SeeDB2” (in variants SeeDB2S and SeeDB2G matched to oil and glycerol immersion, n = 1.52 and 1.47, respectively) and Rapiclear (also with n = 1.52 and 1.47). We measured transparency and tissue shrinkage by comparing freshly dissected brains with cleared brains from dipteran flies, with or without addition of vacuum or ethanol pre-treatments (dehydration and rehydration) to evacuate air from the tracheal system. The results show that ethanol pre-treatment is very effective for improving transparency, regardless of the subsequent clearing medium, while vacuum treatment offers little measurable benefit. Ethanol pre-treated SeeDB2G and Rapiclear brains show much less shrinkage than using the traditional MS/P method. Furthermore, at lower refractive index, closer to that of glycerol immersion, these recently developed media offer outstanding transparency compared to TDE and MS/P. Rapiclear protocols were less laborious compared to SeeDB2, but both offer sufficient transparency and refractive index tunability to permit super-resolution imaging of local volumes in whole mount brains from large insects, and even light-sheet microscopy. Although long-term permanency of Rapiclear stored samples remains to be established, our samples still showed good preservation of fluorescence after storage for more than a year at room temperature.

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