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Abstract Owing to the thermal effect of optical components, it has been challenging for conventional infrared optical imaging system to work in a large temperature range. Wavefront coding technique has been shown to greatly increase tolerance to manufacturing inaccuracies and various defocus, particularly thermal defocus. In this paper, we develop an entirely new infrared imaging modality in 3.7 ∼ 4. 8 μ m waveband, realized with a secondary imaging structure, a non-rotationally symmetric phase mask and a cooled infrared focal plane arrays. The proposed system offers the ability to overcome the temperature limitations of conventional infrared system as well as effectively eliminate the thermal aberration. Proof-of-concept results demonstrate significantly our athermalized optical system perform high-quality images in the operation temperature range of −40 °C to 70 °C. [ABSTRACT FROM AUTHOR]

The hexagonal close-packed (HCP) to face-centered cubic (FCC) phase transition has recently been identified in commercial purity titanium under cryogenic plane-strain compression or conventional rolling. To verify whether the shear deformation could induce this unique HCP-to-FCC phase transition or not, we performed equal channel angular drawing (ECAD) on pure Ti and observed the microstructure changes after deformation by transmission electron microscopy. The results show that the ECAD deformation can induce this phase transition easily. The orientation relationship between the HCP matrix and FCC phase is the well-known prismatic relation 0001HCP//001 and 101¯0HCP//11¯0FCC after ECAD at room temperature. Meanwhile, the FCC-Ti phase processed by ECAD exhibits a high thermal stability with a transus temperature of about 600 °C according to the differential scanning calorimetry technique and annealing tests. However, the FCC-structured Ti has unexpectedly poor stability under high-energy electron beam irradiation, and the FCC-to-HCP reverse transition is attributed to the shear-shuffle mechanism. [ABSTRACT FROM AUTHOR]

Abstract Herein, we present the first report of a high-density nanoblock Laves phase that can be directly precipitated in the Mg-Cd-Yb alloy, with peak-hardness increasing from 50.9 to 66.5 Vickers hardness (HV) during isothermal aging at 200 °C. C s -corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy dispersive X-ray spectroscopy (EDS) mapping results indicate that the nanoblock precipitate is a new, structured (Mg, Cd) 2 Yb ternary intermetallic compound, which has a C14 Laves structure (hcp, space group: P 6 3 / mmc , a = 6.28 Å, c = 10.14 Å). Additionally, the orientation relationship between the (Mg, Cd) 2 Yb precipitate and α-Mg matrix is determined to be (0001) p //(0001) α and [ 1 1 ¯ 00 ] p // [ 11 2 ¯ 0 ] α. This finding is expected to guide the future design of novel, high-strength, and corrosion resistant Mg-Cd alloys. Highlights • Precipitation behavior of the Mg-Cd-Yb alloy was investigated by the novel C s -corrected HAADF-STEM technique. • Remarkable age hardening response was found in present Mg-Cd-Yb alloy due to the profuse nano-precipitations. • The new nano-precipitate was identified to be the ternary (Mg, Cd) 2 Yb Laves phase. • The orientation relationship between nano-precipitate and α-Mg matrix is determined to be (0001) p //(0001) α and [ 1 1 ¯ 00 ] p // [ 11 2 ¯ 0 ] α. [ABSTRACT FROM AUTHOR]

Communication links forming secure telecommunications networks rely on various technologies such as message switching, circuit switching, or packet switching to transmit messages and data. Hamming codes, a family of linear error-correcting codes, are commonly used in communication networks to detect and correct one-bit and two-bit errors. However, reducing power consumption, occupied area, and latency in secure telecommunication networks remains a challenge for future information and communication technology. To address these challenges, emerging technologies like quantum dots offer potential solutions. Quantum-dot cellular automata (QCA) stands as a promising frontier in nanotechnology for enhancing secure telecommunications networks. It opens up the possibility of crafting high-performance, energy-efficient digital circuits. This research harnesses the potential of QCA and introduces groundbreaking innovations: a 3-8 decoder employing a single-layer layout and a 3-input XOR gate with a multi-layer configuration. These components are utilized in the design of an electronic circuit for Hamming codes, incorporating the QCA-based approach. It is important to note that practical implementation in real-world scenarios presents challenges due to the nature of QCA technology. As a result, the evaluation and validation of the proposed designs heavily rely on simulations using QCADesigner. While experimental validation in real-world scenarios is limited, the simulations provide insights into the functionality and feasibility of the suggested designs. By leveraging QCA, the proposed Hamming code circuit significantly enhances cell count, occupied area, and clock latency. The suggested design can be adapted to fit different generating matrices in Hamming codes without requiring drastic modifications to the underlying architecture. [ABSTRACT FROM AUTHOR]

A new method was devised to visualize actin polymerization induced by postsynaptic differentiation signals in cultured muscle cells. This entails masking myofibrillar filamentous (F)-actin with jasplakinolide, a cell-permeant F-actin-binding toxin, before synaptogenic stimulation, and then probing new actin assembly with fluorescent phalloidin. With this procedure, actin polymerization associated with newly induced acetylcholine receptor (AChR) clustering by heparin-binding growth-associated molecule-coated beads and by agrin was observed. The beads induced local F-actin assembly that colocalized with AChR clusters at bead-muscle contacts, whereas both the actin cytoskeleton and AChR clusters induced by bath agrin application were diffuse. By expressing a green fluorescent protein-coupled version of cortactin, a protein that binds to active F-actin, the dynamic nature of the actin cytoskeleton associated with new AChR clusters was revealed. In fact, the motive force generated by actin polymerization propelled the entire bead-induced AChR cluster with its attached bead to move in the plane of the membrane. In addition, actin polymerization is also necessary for the formation of both bead and agrin-induced AChR clusters as well as phosphotyrosine accumulation, as shown by their blockage by latrunculin A, a toxin that sequesters globular (G)-actin and prevents F-actin assembly. These results show that actin polymerization induced by synaptogenic signals is necessary for the movement and formation of AChR clusters and implicate a role of F-actin as a postsynaptic scaffold for the assembly of structural and signaling molecules in neuromuscular junction formation. Key words: acetylcholine receptor cluster * actin * neuromuscular junction * latrunculin * jasplakinolide

In this work, an atomic-scale investigation on the phase structure in the Mg-Gd alloy during isothermal ageing at 230 °C was conducted by means of Cs-corrected high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM). Two types of precipitates including the long-structure β′ (denoted as β L ′) and short-structure β′ (denoted as β S ′) are found to co-exist in the peak-aged Mg-11.5 wt% Gd alloy, which is largely different from the previous reports that only β S ′ or β L ′ precipitate in the peak-aged Mg-Nd, Mg-Y and Mg-Gd binary alloys. According to the micrographs observed in the three directions of [0001] α , [ 11 2 ¯ 0 ] α and [ 10 1 ¯ 0 ] α , both the β L ′ and β S ′ precipitates are confirmed to exhibit an ordered orthorhombic structure and have a same composition of Mg 7 Gd. The β L ′ phase exhibits the truncated lenticular shape, while the β S ′ phase are found to exist in the bridging structure between the β L ′ main bodies. Moreover, four different types of β L ′/β S ′ interface structures can also be observed. [ABSTRACT FROM AUTHOR]

Ultrafast time stretch imaging offers unprecedented imaging speed and enables new discoveries in scientific research and engineering. One challenge in exploiting time stretch imaging in mid-infrared is the lack of high-quality diffractive optical elements (DOEs), which encode the image information into mid-infrared optical spectrum. This work reports the design and optimization of mid-infrared DOE with high diffraction-efficiency, broad bandwidth and large field of view. Using various typical materials with their refractive indices ranging from 1.32 to 4.06 inmid-infrared band, diffraction efficiencies of single-layer and double-layer DOEs have been studied in different wavelength bands with different field of views. More importantly, by replacing the air gap of double-layer DOE with carefully selected optical materials, one optimizedtriple-layer DOE, with efficiency higher than 95% in the wholemid-infrared window and field of view greater than, is designed and analyzed. This new DOE device holds great potential in ultrafast mid-infrared time stretch imaging and spectroscopy. [ABSTRACT FROM PUBLISHER]

1. Ursolic acid (UA) and oleanolic acid (OA) may have important activity relevant to health and disease prevention. Thus, we studied the activity of UA and OA on UDP-glucuronosyltransferases (UGTs) and used trifluoperazine as a probe substrate to test UGT1A4 activity. Recombinant UGT-catalyzed 4-methylumbelliferone (4-MU) glucuronidation was used as a probe reaction for other UGT isoforms. 2. UA and OA inhibited UGT1A3 and UGT1A4 activity but did not inhibit other tested UGT isoforms. 3. UA-mediated inhibition of UGT1A3 catalyzed 4-MU-β-d-glucuronidation was via competitive inhibition (IC500.391 ± 0.013 μM;Ki0.185 ± 0.015 μM). UA also competitively inhibited UGT1A4-mediated trifluoperazine-N-glucuronidation (IC502.651 ± 0.201 μM;Ki1.334 ± 0.146 μM). 4. OA offered mixed inhibition of UGT1A3-mediated 4-MU-β-d-glucuronidation (IC500.336 ± 0.013 μM;Ki0.176 ± 0.007 μM) and competitively inhibited UGT1A4-mediated trifluoperazine-N-glucuronidation (IC505.468 ± 0.697 μM;Ki6.298 ± 0.891 μM). 5. Co-administering OA or UA with drugs or products that are substrates of UGT1A3 or UGT1A4 may produce drug-mediated side effects. [ABSTRACT FROM PUBLISHER]