Free-space remote sensing of rotation at photon-counting level

The rotational Doppler effect associated with light's orbital angular momentum (OAM) has been found as a powerful tool to detect rotating bodies. However, this method was only demonstrated experimentally on the laboratory scale under well controlled conditions so far. And its real potential lies at the practical applications in the field of remote sensing. We have established a 120-meter long free-space link between the rooftops of two buildings and show that both the rotation speed and the rotational symmetry of objects can be identified from the detected rotational Doppler frequency shift signal at photon count level. Effects of possible slight misalignments and atmospheric turbulences are quantitatively analyzed in terms of mode power spreading to the adjacent modes as well as the transfer of rotational frequency shifts. Moreover, our results demonstrate that with the preknowledge of the object's rotational symmetry one may always deduce the rotation speed no matter how strong the coupling to neighboring modes is. Without any information of the rotating object, the deduction of the object's symmetry and rotational speed may still be obtained as long as the mode spreading efficiency does not exceed 50 %. Our work supports the feasibility of a practical sensor to remotely detect both the speed and symmetry of rotating bodies

Supplementary document for High-speed super-resolution imaging with compressive imaging-based structured illumination microscopy - 5780239.pdf

Data acquisition and image reconstruction of CISI

Additional file 1 of Biomechanical analysis of the maxillary sinus floor membrane during internal sinus floor elevation with implants at different angles of the maxillary sinus angles

Supplementary Material

Extremely Small Iron Oxide Nanoparticles with pH-Dependent Solubility Transition as T₁/T₂ Switchable Contrast Agents for MRI

Extremely small iron oxide nanoparticles (ESIONPs), which have a switchable contrast signal and a favorable biocompatibility, are gaining considerable attention as smart magnetic resonance imaging (MRI) contrast agents (CAs). Adaptive MRI CAs could improve the accuracy of tumor diagnosis because they realize rapid imaging signal conversion under an endogenous stimulus. Herein, based on the hydrophilic to hydrophobic transition of polymers, we propose a pH-responsive T1/T2 switchable ESIONP contrast agent. ESIONPs are functionalized at the surface with adamantane groups through a polyethylene glycol (PEG) chain, and subsequently, a stimuli-responsive polymer (PSDM) with pH-dependent solubility is introduced through the host–guest interaction between adamantane and β-cyclodextrin (β-CD). The obtained ESIONPs-PEG-PSDM is equipped with remarkable pH responsiveness, which triggers the aggregation of ESIONPs under the tumor acid condition, leading to the switch from a T1 to a T2 contrast agent. In vivo MRI experiments show that the T2 contrast signal is selectively enhanced at the tumor location after injection of ESIONPs-PEG-PSDM. Therefore, ESIONPs-PEG-PSDM with pH-induced hydrophilic to hydrophobic transition is a potential smart MRI contrast agent for precise tumor diagnosis

Transformation of Ordered Albite into Kaolinite: Implication for the “Booklet” Morphology

Kaolinization of feldspars is widespread in various geological environments including weathering and hydrothermal environments. However, the mechanisms of such mineral transformation and kaolinite formation remain obscure. In this study, the experiments of the transformation of ordered albite into kaolinite were carried out under hydrothermal conditions to reveal the transformation mechanism involved and the formation mechanism of kaolinite aggregates with a “booklet” morphology. The obtained results demonstrated that a complete dissolution–recrystallization mechanism is responsible for the transformation process since the configurations and linkages of Al–O4 tetrahedrons in ordered albite are significantly different from those of the Al–O2(OH)4 octahedral sheets in kaolinite. During the dissolution of precursor albite, Si might be released from the structure of albite prior to Al. Subsequently, four-coordinated Al (AlIV) would be progressively converted into six-coordinated Al (AlVI) through hydration, which is beneficial to the formation of kaolinite. For albite with a large particle size, the alteration products were kaolinite aggregates with a “booklet” morphology, which were formed by the attachment of generated intermediate components of Al and Si during the dissolution of albite and subsequent crystallization of kaolinite platelets or layers stacking up to a micron height most likely along the albite cleavages. However, the crystallinity and layer stacking order of the “booklet” kaolinite aggregates were low. These findings provide insights for a better understanding of the transformation of feldspars into kaolinite and the formation of kaolinite aggregates with a “booklet” morphology under both natural and experimental conditions

Biodegradable Nanoglobular Magnetic Resonance Imaging Contrast Agent Constructed with Host–Guest Self-Assembly for Tumor-Targeted Imaging

Gadolinium-based macromolecular magnetic resonance imaging (MRI) contrast agents (CAs) have attracted increasing interest in tumor diagnosis. However, their practical application is potentially limited because the long-term retention of gadolinium ion in vivo will induce toxicity. Here, a nanoglobular MRI contrast agent (CA) PAMAM-PG-<i>g</i>-s-s-DOTA­(Gd) + FA was designed and synthesized on the basis of the facile host–guest interaction between β-cyclodextrin and adamantane, which initiated the self-assembly of poly­(glycerol) (PG) separately conjugated with gadolinium chelates by disulfide bonds and folic acid (FA) molecule onto the surface of poly­(amidoamine) (PAMAM) dendrimer, finally realizing the biodegradability and targeting specificity. The nanoglobular CA has a higher longitudinal relaxivity (<i>r</i>₁) than commercial gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA), showing a value of 8.39 mM^–1 s^–1 at 0.5 T, and presents favorable biocompatibility on the observations of cytotoxicity and tissue toxicity. Furthermore, MRI on cells and tumor-bearing mice both demonstrate the obvious targeting specificity, on the basis of which the effective contrast enhancement at tumor location was obtained. In addition, this CA exhibits the ability of cleavage to form free small-molecule gadolinium chelates and can realize minimal gadolinium retention in main organs and tissues after tumor detection. These results suggest that the biodegradable nanoglobular PAMAM-PG-<i>g</i>-s-s-DOTA­(Gd) + FA can be a safe and efficient MRI CA for tumor diagnosis

VAMP724 and VAMP726 are involved in autophagosome formation in <i>Arabidopsis thaliana</i>

Macroautophagy/autophagy, an evolutionarily conserved degradative process essential for cell homeostasis and development in eukaryotes, involves autophagosome formation and fusion with a lysosome/vacuole. The soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins play important roles in regulating autophagy in mammals and yeast, but relatively little is known about SNARE function in plant autophagy. Here we identified and characterized two Arabidopsis SNAREs, AT4G15780/VAMP724 and AT1G04760/VAMP726, involved in plant autophagy. Phenotypic analysis showed that mutants of VAMP724 and VAMP726 are sensitive to nutrient-starved conditions. Live-cell imaging on mutants of VAMP724 and VAMP726 expressing YFP-ATG8e showed the formation of abnormal autophagic structures outside the vacuoles and compromised autophagic flux. Further immunogold transmission electron microscopy and electron tomography (ET) analysis demonstrated a direct connection between the tubular autophagic structures and the endoplasmic reticulum (ER) in vamp724-1 vamp726-1 double mutants. Further transient co-expression, co-immunoprecipitation and double immunogold TEM analysis showed that ATG9 (autophagy related 9) interacts and colocalizes with VAMP724 and VAMP726 in ATG9-positive vesicles during autophagosome formation. Taken together, VAMP724 and VAMP726 regulate autophagosome formation likely working together with ATG9 in Arabidopsis.</p

Supplementary document for A flexible and accurate total variation and cascaded denoisers-based image reconstruction algorithm for hyperspectrally compressed ultrafast photography - 6744828.pdf

Supplemental Documen

Single-shot polarization-resolved ultrafast mapping photography

Single-shot ultrafast optical imaging plays a very important role in the detection of transient scenes, especially in capturing irreversible or stochastic dynamic scenes. To break the limit of time response speed of electronic devices, such as charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) detectors, ultrafast optical imaging techniques usually convert the time information of a transient scene into the wavelength, angle, space or spatial frequency of the illumination light in previous studies. In this work, we propose a novel polarization-resolved ultrafast mapping photography (PUMP) technique by converting the time information into the polarization. Here, the spatiotemporal information of a dynamic scene is loaded into a rotationally polarized illumination laser pulse, and a polarization filtering in imaging detection and a deconvolution algorithm in image reconstruction are used to extract the original dynamic scene. In our PUMP system, the temporal resolution is 850 fs, the spatial resolution is 28.5 lp/mm at 700 micrometer by 700 micrometer field of view, and the number of frames is 16. By using PUMP, a spatiotemporal dynamics of femtosecond laser ablation in an indium tin oxide film on glass substrate is successfully captured. PUMP provides a new solution for measuring the transient scenes in a snapshot, which will bring a very wide range of applications in the field of ultrafast science

Additional file 1 of Modulation of ZnO Nanostructure for Efficient Photocatalytic Performance

Additional file 1. PL and absorption spectra of the ZnO nanostructures with and without Au NPs